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BACKGROUND OF THE INVENTION
1. Field of Invention
This invention is directed to systems and methods for maintaining and/or enhancing operation of fluid ejection systems.
2. Description of Related Art
Fluid ejection systems, such as drop on demand liquid ink printers, use various methods to eject fluids, including but no limited to piezoelectric, acoustic, phase change, wax based and thermal systems. These systems include at least one fluid ejector from which droplets of fluid are ejected towards a receiving medium, such as a sheet of paper. A channel is defined within each fluid ejector. The fluid is disposed in the channel. Droplets of fluid can be expelled as required from orifices or nozzles at the end of the channels using power pulses.
In some fluid ejection systems, such as, for example, drop on demand thermal ink jet printers, a pressurized reservoir of ink is connected to a plurality of ink channels and, subsequently, the nozzles, via a fluid supply manifold. The fluid supply manifold contains internal, closed walls defining a chamber with an ink fill hole. The fluid supply manifold receives ink from the ink reservoir and distributes it via internal passageways to the plurality of ejector channels. A plurality of sets of channels and associated fluid supply manifolds can be defined within a single fluid ejection system or printhead. One or more filters can be situated within the fluid supply manifold and/or entrance to each channel. The filters are designed to collect solidified waste fluid and other contaminants, bubbles, debris, residue and/or deposits or the like that can negatively impact the fluid ejector.
U.S. Pat. No. 4,639,748 to Drake et al. discloses an internal, integrated filtering system and fabrication process for an ink jet fluid supply manifold. Small passageways are defined within the fluid supply manifold to deliver ink to a plurality of ink channels. Each of the passageways has smaller cross-sectional flow areas than the ink channels. Therefore, any contaminating particle in the ink that would have passed to the ink channels will be filtered or stopped by the passageways before entering the ink channels.
In drop-on-demand thermal ink jet printers, a heating element normally located in the ink channel causes the ink to form bubbles. By applying a voltage across the heating element, such as a heater transducer or resistor, a vapor bubble is formed. The bubbles force the droplets of ink from the nozzle onto the sheet of receiving medium. The channel is then refilled by capillary action from the ink reservoir via the fluid supply manifold.
SUMMARY OF INVENTION
While ejecting fluid, fluid drawn from the fluid reservoir is directed through the passageways of the fluid supply manifold to each ejector channel. Contaminants, bubbles, debris, and/or residue located in the fluid reservoir can travel to the ejector channels. Filters within the fluid supply manifold and/or design techniques of the fluid supply manifold often trap the contaminants, bubbles, debris, and/or residue before they reach the fluid channels. However, some contaminants, bubbles, debris, and/or residue can reach the inlet of the ejector channels. Just as contaminants, bubbles, debris, residue, and/or deposits can accumulate on the face of the ejector head, thus clogging ejector nozzles and resulting in a deleterious effect on ejection quality, so too does the accumulation of contaminants, bubbles, debris, and/or residue at the inlet of the ejector channels negatively impact the ejection quality.
Removing solidified waste fluid and other contaminants, bubbles, debris, residue and/or deposits or the like from the face of the ejector head can be accomplished using any number of available methods, including, but not limited to, using a wiper blade, using a washing unit, and any combination of wiping and washing. While these have proven effective in removing solidified fluid or minute particles from the face of the ejector head, similar methods for clearing ejector channel inlets are not available. As a result, the ejection operation is diminished and slowed because several partial ejection swaths are required to cover the defects.
The inventor has determined that ejecting the fluid droplets, such as ink, from the ejector nozzle results in a back pressure within the ejector channel. This back force is directed out the channel inlet, often ejecting any residual fluid remaining in the channel back towards the fluid supply manifold.
This invention provides systems and methods for maintaining fluid ejection channels.
This invention separately provides systems and methods that remove at least some debris from a channel inlet.
This invention separately provides systems and methods for driving a fluid ejection system using a fluid ejection sequence.
This invention further provides systems and methods that move to a less harmful position at least some debris that interferes with proper fluid ejection from the ejector channels of the fluid ejection system using the fluid ejection sequence.
In various exemplary embodiments of the systems and methods according to this invention, at least some of a plurality of fluid ejectors are fired in a sequential pattern. In various exemplary embodiments, firing a fluid ejector results in a back pressure wave that moves debris, residue, contaminants, deposits or the like back out of the inlet of the fired fluid channel and/or any filter elements positioned on or near the inlet. In various exemplary embodiments, sequentially firing the fluid ejectors causes the back-ejected debris, residue, contaminants, deposits or the like within the fluid supply manifold to move along the direction of the firing sequence. In various exemplary embodiments of the systems and methods according to this invention, the moved contaminants, bubbles, debris, residue and/or deposits or the like can be deposited into locations within the fluid supply manifold that are not associated with operative fluid ejector channels.
In various exemplary embodiments of the systems and methods according to this invention, the fluid ejectors are fired in a sequential pattern within blocks of the fluid ejectors. For example, a fluid ejector head with, for example, 120 fluid ejectors can fire 1 out of every 20 fluid ejectors. Therefore, during a first period of the sequence, ejectors at positions 1 , 21 , 41 , 61 , 81 and 101 fire. Each fluid ejector is fired at least one time, and, in various exemplary embodiments, is fired multiple times, such as, for example, up to 100 times, before the next fluid ejector in the sequence is fired. Then, during a second period of the sequence, the fluid ejectors at positions 2 , 22 , 42 , 62 , 82 , and 102 fire. Groups of fluid ejectors are fired in this manner until all 120 of the fluid ejectors have fired. This moves any debris, residue, contaminants, deposits or the like within the fluid supply manifold in the direction of firing, i.e., from position 20x+1 to position 20x+20.
These and other features and advantages of this invention are described in, or are apparent from, the following detailed description of various exemplary embodiments of the systems and methods according to this invention.
BRIEF DESCRIPTION OF THE DRAWINGS
Various exemplary embodiments of this invention will be described in detail, with reference to the following figures, wherein:
FIG. 1 is a partial perspective view of an exemplary fluid ejection system that includes a fluid ejector head with which the systems and methods of the invention are usable;
FIG. 2 illustrates one exemplary embodiment of a reservoir, a fluid supply manifold, and the channels of the fluid ejector head of FIG. 1;
FIG. 3 is a side cross-sectional view of one exemplary embodiment of a fluid ejector head;
FIG. 4 is a rear view of one exemplary embodiment of an ejector channel;
FIG. 5 illustrates one exemplary embodiment of an n period of the first exemplary embodiments of the fluid drop ejection sequence according to this invention;
FIG. 6 illustrates one exemplary embodiment of an (n+1) th period of the first exemplary embodiment of the fluid drop ejection sequence according to this invention;
FIG. 7 illustrates one exemplary embodiment of an (n+2) th period of th e first exemplary embodiment of the fluid drop ejection sequence according to this invention;
FIG. 8 illustrates one exemplary embodiment of a last period of the first exemplary embodiment of the fluid drop ejection sequence according to this invention;
FIG. 9 illustrates one exemplary embodiment of discrete segments of second-to-last periods of a second exemplary embodiment of the fluid drop ejection sequence according to this invention;
FIG. 10 illustrates one exemplary embodiment of discrete segments of next-to-last periods of the second exemplary embodiment of the fluid drop ejection sequence according to this invention;
FIG. 11 illustrates one exemplary embodiment of discrete segments of last periods of the second exemplary embodiment of the fluid drop ejection sequence according to this invention; and
FIG. 12 is a flow chart outlining an exemplary embodiment of a method for fluid ejection sequencing.
DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS
Various exemplary embodiments of the systems and methods according to this invention allow fluid ejection systems to be maintained by using firing sequences of the fluid ejectors according to this invention. The mechanisms and techniques used for fluid ejection according to this invention allow moveable contaminants, bubbles, debris, residue and/or deposits or the like within a fluid supply manifold and/or inlet filters to be moved from ejector channel inlets using a back pressure wave resulting from firing of the fluid ejectors. In various exemplary embodiments, contaminants, bubbles, debris, residue and/or deposits or the like are moved within the fluid supply manifold in the direction of the firing sequence of the fluid ejectors.
In general, the contaminants, bubbles, debris, residue and/or deposits or the like dislodged by firing the fluid ejectors are moved into less-harmful positions within the fluid supply manifold. Such less harmful positions within the fluid supply manifold can include areas in which no fluid ejectors are connected, areas in which non-operative or dummy fluid ejector channels are connected, areas in which operative but de-selected fluid ejector channels are formed, or the like. It should be appreciated that, in various exemplary fluid ejection systems, fluid ejector channels can be de-selected for any of a variety of reasons. Such reasons include that a particular fluid ejector fails to properly operate, cannot be recovered from a particular failure mode, or the like. Fluid ejectors can also be de-selected based on a particular print algorithm used to select the operative fluid ejectors, such as during printing of partial and/or overlapping swaths. In various exemplary embodiments of the systems and methods of this invention, contaminants, bubbles, debris, residue and/or deposits or the like dislodged by firing the fluid ejectors can be moved or deposited into reservoirs, such as, for example, dummy and/or non-operative ejector channels or de-selected ejector channels that are next to the fluid ejectors or that are at an end of a row of fluid ejectors.
The following detailed description of various exemplary embodiments of the fluid ejection systems according to this invention may refer to one specific type of fluid ejection system, an ink jet printer, for the sake of clarity and familiarity. However, it should be appreciated that the principles of this invention, as outlined and/or discussed below, can be equally applied to any known or later-developed fluid ejection systems, beyond any ink jet printers specifically discussed herein.
FIG. 1 is a partial perspective view of an exemplary embodiment ink jet system 100 that includes a fluid ejector head 110 that the systems and methods of the invention are usable with to reduce the effects of contaminants, bubbles, debris, residue and/or deposits or the like on the operation of fluid channels of the fluid ejector head 110 .
As shown in FIG. 1, the fluid ejector head 110 is moveable along guide rails 160 in the directions indicated by the arrow 162 . A receiving medium 200 is moveable in the directions indicated by the arrow 210 , which is substantially perpendicular to the directions of movement of the fluid ejector head 110 .
In operation, the fluid ejector head 110 is moved along a linear path. The length of the linear path is approximately defined by the sides of the receiving medium 200 so that the fluid ejector head 110 is capable of ejecting fluid along substantially the entire width of the receiving medium 200 . When the fluid ejector head 110 reaches each side of the receiving medium 200 , the receiving medium 200 is incrementally advanced in one of the directions of arrows 210 so that the fluid ejector head 110 is capable of ejecting fluid along substantially the entire length of the receiving medium 200 .
The fluid ejector head 110 includes a channel body 130 and an aperture plate 120 at a side of the fluid ejector head 110 that is adjacent to the receiving medium 200 . The aperture plate 120 and the channel body 130 can be disposed adjacent to or substantially adjacent to each other, with the aperture plate 120 being disposed facing the receiving medium 200 . The aperture plate 20 and the channel body 130 can be integral and/or can be connected to each other by any suitable method or structure, such as, for example, by glue, epoxy, welding etc.
It should be appreciated, however, the aperture plate 120 and the channel body 130 do not have to be directly connect to each other. For example, other elements can be disposed between the aperture plate 120 and the channel body 130 . Alternatively, the aperture plate 120 and the channel body 130 do not have to be separate elements.
FIG. 2 illustrates a top view of one exemplary embodiment of the components that comprise the fluid ejector head 110 . As shown in FIG. 2, in this first exemplary embodiment, the channel body 130 contains a fluid reservoir 140 , a fluid supply manifold 150 , and a plurality of channels 132 , which are substantially aligned with the ejector nozzles of the aperture plate 120 of the fluid ejector head 110 . It should be appreciated that the fluid ejector head 110 may contain any number of channels 132 .
The aperture plate 120 can be placed on or over the channel body 130 . As fluid is ejected from the fluid ejectors channels 132 defined in the channel body 130 , the fluid subsequently passes through the nozzles of the aperture plate 120 and onto the receiving medium 200 .
It should be appreciated that the plurality of channels 132 of the fluid ejector head 110 , as shown in FIG. 2, may be substantially aligned in the direction of the width of the aperture plate 120 . The ejector channels 132 can be spaced at any desired distance, which may be determined based on a function of the fluid ejection system 100 . Further, it should be appreciated that, as shown in FIG. 2, in various exemplary embodiments, the plurality of channels 132 are formed as a single row. However, in various other exemplary embodiments, two or more rows of the channels 132 may be used, as required, by the fluid ejection system 100 .
The fluid reservoir 140 can be any device capable of holding fluid to be used in the fluid ejection system 100 . The fluid supply manifold 150 can be any device capable of receiving fluid from the fluid reservoir 140 and distributing the fluid to the plurality of ejector channels 132 . It should be appreciated that the fluid reservoir 140 and the fluid supply manifold 150 , while depicted separately from each other and from the channel body 130 , may not necessarily be separate and distinct components. Thus, the design, functions and/or operations of the fluid reservoir 140 , the fluid supply manifold 150 and/or the channel body 130 may be carried out by any number of distinct components.
FIG. 3 is a side cross-sectional view of one exemplary embodiment of a fluid ejector head 110 . As shown in FIG. 3, the fluid ejector head 110 includes the fluid supply manifold 150 , the channel body 130 , and the aperture plate 120 . The fluid supply manifold 150 , as shown in FIG. 3, includes a fluid inlet 152 and a fluid distribution passage 154 . Fluid from the fluid reservoir 140 enters the fluid distribution passage 154 of the fluid supply manifold 150 via the fluid inlet 152 . In operation, the fluid supply manifold 150 delivers the fluid to a plurality of the ejector channels 132 . In various exemplary embodiments, the fluid ejector head 110 can contain a plurality of fluid supply manifolds 150 providing fluid to a plurality of distinct sets of the ejector channels 132 .
Alternatively, the fluid ejector head 110 can include a fluid supply manifold 150 in which the fluid distribution passage is divided into distinct portions that are not necessarily in fluid communication with each other. In this case, each such distinct portion may have its own fluid inlet 152 . Each distinct portion of the fluid distribution passage 154 supplies fluid primarily to the associated set of the plurality of ejector channels 132 . It should be appreciated that the design of the fluid ejector head 110 , including the fluid supply manifold 150 , ejector channels 132 , and aperture plate 120 will be obvious and predictable to those skilled in the art.
FIG. 4 is a cross-sectional view taken along the line 4 — 4 of FIG. 3 . FIG. 3 depicts the channel inlet 134 from the fluid distribution passage 154 to the ejector channel 132 . The channel inlet 134 allows fluid from the fluid supply manifold 150 to enter into the ejector channel 132 . In various exemplary embodiments, the channel inlet 134 is smaller than the cross-sectional flow area of the ejector channel 132 . It should be appreciated that the particular size and shape of the channel inlet 134 will be obvious and predictable to those skilled in the art.
Although not depicted, it should be further appreciated that the fluid supply manifold 150 can employ various filtering techniques, including, but not limited to, filters and unique fluid supply manifold passageway designs to contain and/or trap contaminants, bubbles, debris, and/or residue within the fluid supply manifold 150 . Such contaminants, bubbles, debris, and/or residue not trapped and/or contained within the fluid supply manifold 150 can accumulate at the channel inlet 134 and/or enter into the channel 132 . When the debris, residue, contaminants, deposits or the like collect at or within the channel inlet 134 , the cross-sectional flow area of the channel inlet 134 can become significantly reduced. This reduces the amount of fluid that can flow into the fluid channel 132 between a last firing and a next firing of that channel 132 . A partially-filled fluid channel 132 will generally not eject a drop of fluid correctly. Additionally, as the fluid acts to cool the resistive heater of a thermal fluid ejector, the resistive heater can overheat and fail due to such improper filling.
If the debris, residue, contaminants, deposits or the like collect in the fluid channel 132 itself, these same problems can occur. Additionally the debris, residue, contaminants, deposits or the like in the ejector channel 132 can become lodged in the nozzle or can decompose, coat the resistive heater of a thermal system or otherwise detrimentally affect the fluid channel 132 and/or the nozzle.
FIGS. 5-8 illustrate a number of periods of a first exemplary embodiment of the ejector firing sequence according to this invention. As shown in FIGS. 5-8, the fluid supply manifold 150 , having a number of end walls 156 , provides the fluid to the plurality of ejector channels 132 . In FIGS. 5-8, fluid flows in direction 136 through a plurality of nozzles. As shown in FIG. 5, during an n th period of the fluid drop ejection sequence, a fluid drop 138 is ejected from the n th channel 132 . It should be appreciated that, in this first exemplary embodiment, and as well as any other exemplary embodiment according to this invention, each period can include one or more firings of the current ejector channel 132 . Thus, in various exemplary embodiments, a large number of firings, such as 100 firings, of each ejector channel 132 can occur during each period.
During operation, particles 170 can collect and/or form on, in and/or near the channel inlet 134 and can adversely affect the fluid drop 138 exiting the ejector channel 132 . These adverse effects include, but are not limited to, restricting and/or blocking the channel inlets 134 . The particles 170 can be any substance that is capable of obstructing the channel inlet 134 , including solidified fluid, dust, and the like. The particles 170 can also be bubbles of air or the like that are present in the fluid. In general, the particles 170 are anything other than fluid that can freely flow through the channel inlet 134 .
When fluid ejects from the ejector channels 132 , a back pressure pulse 139 is directed backwards from the channel inlet 134 into the fluid supply manifold 150 , often ejecting any residual fluid remaining in the ejector channel 132 back towards the fluid supply manifold 150 . The resulting back pressure pulses 139 tend to dislodge the particles 170 in a direction 172 towards and possible pass the adjacent (n+1) th ejector channel 132 . In various exemplary embodiments, the force of the back pressure pulses 139 dislodges the particles 170 . However, it should be appreciated that some other physical process that occurs in response to the back pressure pulses 139 being directed back into the fluid supply manifold 150 may be responsible for dislodging the particles. 170 .
Although the particles 170 are depicted as dislodging in the direction 172 , it should be appreciated that the direction that any given particle 170 moves is predicated on its position on and/or around the n th channel inlet 134 and/or the force and/or angle with which any given back pressure pulse 139 impacts that particular particle 170 . Subsequently, a dislodged particle 170 can land on part or portion of other channel inlets 134 , including, but not limited to that space between the ejector channels 132 . For example, in FIG. 5, the particles 170 can be dislodged in the direction 172 towards the n+1 th ejector channel 132 but could land between the n th ejector channel 132 and the n+1 th ejector channel 132 .
Accordingly, in various exemplary embodiments of the firing sequence according to this invention, each ejector channel 132 is fired a plurality of times, such as, for example, 100 times. In various exemplary embodiments, it is believed that, each time a given ejector channel 132 is fired, the resulting back pressure pulse 139 further dislodges additional particles 170 and/or further moves of the particles 170 away from that ejector channel 132 . In various exemplary embodiments, the size of the back pressure pulse 139 and the number of times each ejector channel 132 is fired combines move the particles 170 from around the n th ejector channel 132 to at least more than halfway past the next n+1 th ejector channel 132 .
This will tend to place those particles in a position such that, during the (n+1) th period, when that next n+1 th ejector channel 132 is fired, those particles 170 will tend to move towards the next n+2 th ejector channel 132 and not back toward the n th ejector channel 132 . This will also tend, during the n th period, to move any particles 170 near the channel inlet 134 of the n+1 th ejector channel 132 that are relatively closer to the n th ejector channel 132 than to the n+2 th ejector channel 132 toward the n+2 th ejector channel 132 . Thus, those particles 170 will also tend to be placed on a position such that, when the n+1 th ejector channel 132 is fired during those (n+1) th period, those particles 170 will also tend to move towards the n+2 th ejector channel 132 instead of back towards the n th ejector channel 132 .
It should be appreciated that the number of pulses to be fired during each period can be predetermined, could have been empirically determined during design, development and/or manufacturing of the fluid ejector head as that number that is sufficient to adequately move the particles 170 , or could be dynamically determined during operation based on the degree of adverse printing effects or the like. This dynamic determination can be performed by the user or by a controller (not shown).
FIG. 6 illustrates an exemplary embodiment of the (n+1) th period of the first exemplary embodiment of the fluid ejection sequence. After the n th ejector channel 132 depicted in FIG. 5 has been fired the one or more times, the particles 170 have moved from the positions shown in FIG. 5 towards the positions shown in FIG. 6 . FIG. 6 shows the (n+1) th ejector channel 132 ejecting a drop 138 . The resulting back pressure pulse 139 dislodges or further moves the particles 170 in the direction 172 . The particles 170 will generally tend to include not only those particles dislodged from previous ejector channels 132 , but also additional particles 170 dislodged from the n+1 th channel 132 .
Also as discussed above, the direction that the particles 170 moves in FIG. 6 is predicated on its position on, in and/or around the channel inlet 134 and/or the force and/or angle with which the back pressure pulse 139 impacts the particles 170 . Subsequently, the particles 170 can land on part or portion of other channel inlets 134 , including, but not limited to that space between the ejector channel 132 .
FIG. 7 illustrates an exemplary embodiment of the (n+2) th period of the first exemplary embodiment of the fluid ejection sequence. After the (n+1) th ejector channel 132 depicted in FIG. 6 has been fired the one or times, the particles 170 have moved from the positions shown in FIG. 6 towards the positions shown in FIG. 7 . FIG. 7 shows the (n+2) th ejector channel 132 ejecting a drop 138 . The resulting back pressure pulse 139 dislodges or further moves the particles 170 in the direction 172 . The particles 170 will generally tend to include not only those particles dislodged from the previous ejector channels 132 , but also additional particles 170 dislodged from (n+2) th ejector channel 132 .
Also as discussed above, the direction that the particles 170 moves in FIG. 7 is predicated on its position on, in, and/or around the channel inlet 134 and/or the force and/or angle with which the back pressure pulse 139 impacts the particles 170 . Subsequently, the particles 170 can land on part or portion of other channel inlets 134 , including, but not limited to that space between the ejector channels 132 .
FIG. 8 illustrates an exemplary embodiment of the m th or last period of the first exemplary embodiment of the fluid ejection sequence. After the (n+2) th ejector channel 132 depicted in FIG. 7, and any intervening ejection channel(s) have been fired the one or more times, the particles 170 have moved from the positions shown in FIG. 7 towards the positions shown in FIG. 8 . FIG. 8 shows the m th ejector channel 132 ejecting a drop 138 . The resulting back pressure pulse 139 dislodges or further moves the particles 170 in the direction 172 . The particles 170 will generally tend to include not only those particles dislodged from all of the previous ejector channels 132 , but also additional particles 170 dislodged from m th ejector channel 132 .
Also as discussed above, the direction that the particles 170 moves in FIG. 8 is predicated on its position on, in, and/or around the channel inlet 134 and/or the force and/or angle with which the back pressure pulse 139 impacts the particles 170 . Subsequently, the particles 170 can land on part or portion of other channel inlets 134 , including, but not limited to that space between the ejector channels 132 .
As shown in FIG. 8, non-operative ejector channels 180 , or a space where an ejector channel 132 could have been formed but has not been, are situated after the m th or last ejector channel 132 . Although three non-operative ejector channels 180 are shown, it should be appreciated that any number of non-operative ejector channels 180 , such as, for example, dummy ejector channels, failed ejector channels and/or de-selected ejector channels or size of the space can be used. As shown in FIG. 8, the dislodged particles 170 accumulate in and/or around the non-operative ejector channels 180 .
It should be appreciated that the ejector channels 132 shown in FIGS. 5-8 represent any segment of an array of the fluid ejector channels 132 . For example, the ejector channels 132 in FIGS. 5-8 can be at the beginning, the middle, or end of an array of ejector channels 132 .
It should be further appreciated that, though it is not depicted, the sequential fluid ejection illustrated in FIGS. 5-7 with respect to the n th , (n+1) th , and (n+2) th ejector channels 132 , respectively, continues with the sequential firing of the remaining ejector channels 132 until all the ejector channels 132 in a given array have fired. Any dislodged particles 170 that move along the array of ejector channels 132 as a result of the back pressure pulse 139 generated by the sequential firing can be dislodged and/or moved by the m th or last ejector channel 132 that fires into an area 182 that collects such moveable contaminants. Any particle 170 dislodged or removed from the channel inlets 134 during the sequential firing process and deposited onto the area 182 away from the operative ejector channels 132 , such as, for example, a non-operative channel 180 .
FIGS. 9-11 show a number of consecutive periods of a second exemplary embodiment of the ejector firing sequence and a second exemplary embodiment of the ejector body 130 and the fluid supply manifold 150 according to this invention. In FIGS. 9-11, in this second exemplary embodiment of the firing sequence, the ejector channels 132 within the fluid ejector body 130 are, at least operationally, divided into discrete sections separate from the others by various ones of the end, or partition, walls 156 . In the specific embodiment shown in FIGS. 9-11, the ejector channels 132 are divided, at least operationally, into sections of 40 ejector channels 132 . Although the ejector channels 132 in FIGS. 9-11 are divided at least operationally into sections of 40 ejector channels 132 , it should be appreciated that the array of ejector channels 132 can be divided into at least operational sections of any desired number, for example, sections of 10 channels, 20 channels, or 30 channels. It should be further appreciated that the ejector channels 132 shown in FIGS. 9-10 could be depicting the beginning, middle, or end sections of a row of channels.
In FIGS. 9-11, fluid flows in the direction 136 through the plurality of ejector channels 132 , ejecting drops 138 from the ejector channels 132 . As shown in FIGS. 9-11, zero, one or more non-operative channels 180 of the area 182 are associated with each at least operationally-associated set of 40 operative ejector channels 132 . Although only one non-operative channel 180 is shown associated with each at least operationally-associated set of 40 operative ejector channels 132 , it should be appreciated that any number of non-operative channels 180 , or a space of any appropriate size, can be associated with each at least operationally-associated set of operative ejector channels 132 in the area 182 .
In various exemplary embodiments, sequentially firing the fluid drops 138 through the ejector channels 132 can be enhanced by using a regular firing pattern. For example, by firing drops simultaneously through certain ones of the ejector channels 132 using a pattern, such as a pattern where one out of every 40 ejector channels 132 is fired, the resulting back pressure pulse 139 can move the contaminants, bubbles, debris, residue and/or deposits 170 or the like that has collected in and/or around the channel inlet 134 in the direction of the firing sequence for more than a single ejector channel at a time.
As shown in FIG. 9, fluid is ejected at the same time out of the ejector channels 132 at positions n, n+40, n+80, n+120 and for a given number of drops. Any contaminants, bubbles, debris, residue and/or deposits 170 or the like are moved from the channel inlet 134 of the n+40x channels 132 in the direction 172 . In the next period of the firing sequence, as depicted in FIG. 10, fluid is ejected at the same time from the next set of the ejector channels 132 at the positions n+1, n+41, n+81, and n+121, etc. and for a given number of drops. The sequential firing sequence continues as depicted in FIG. 11 with drops 138 being ejected through the next set of the ejector channels 132 at the positions n+2, n+42, n+82, and n+122. Eventually, as a result of the back pressure pulses 139 generated by sequentially firing the drops of fluid through the ejector channels 132 , any contaminants, bubbles, debris, residue and/or deposits 170 or the like end up in the area 182 .
It should be appreciated that any number of drops 138 can be ejected by each of the ejector channels 132 . Thus, for example, in various exemplary embodiments, each ejector channel 132 ejects the same number of drops 138 . In contrast, in various other exemplary embodiments, each ejector channel 132 ejects a particular number of drops 138 , which, in general, will be different from at least one other one of the ejector channels 132 .
It should also be appreciated that the fired ejector channels 132 , although shown immediately adjacent to each other in FIGS. 1-11, could be spaced from each other by one or more intervening operative or non-operative ejector channels 132 . Thus, if the particles 170 dislodged by the back pressure pulses 139 are displaced by two or more channel separations, it may be advantageous to skip one or more channels between a pair of driven ejector channels 132 .
FIG. 12 is a flowchart outlining one exemplary embodiment of a method for ejecting fluid in a sequence according to this invention. As shown in FIG. 12, operation of the method begins in step S 100 and continues to step S 110 , where the first set of channels to be fired is selected. Then, in step S 120 , the current set of channels is fired a given number of times to move any contaminants, bubbles, debris, residue and/or deposits back from the channel inlet into the fluid supply fluid supply manifold toward at least a next channel. Next, in step S 130 , a determination is made whether there is an additional set of channels that need to be fired. If no additional set of channels needs to be fired, operation continues to step S 140 . Otherwise, operation jumps to step S 150 .
In step S 140 , the next set of nozzles are selected as the current set to be fired. Operation then jumps back to step S 120 . In contrast, in step S 150 , operation of the method ends.
It should be appreciated that, in various exemplary embodiments, the method outlined above is performed during a maintenance operation to move any of the contaminants, bubbles, debris, residue, and/or deposits that may have collected in and/or around the channel inlet 134 to less-harmful positions. Such a maintenance operation can be performed as part of a regular overall maintenance operation or can be performed when desired by the operator. It should further be appreciated that the method outlined above could be performed during normal printing operations. In particular, the method outlined above could be performed when an analysis of the print data indicates that the desired sequence of firing the fluid ejectors at least the desired number of times can be performed at the same time that the fluid is ejected to form the desired pattern of ejected fluid on the receiving medium.
While this invention has been described in conjunction with the exemplary embodiments outlined above, 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 as set forth above, are intended to be illustrative, not limiting. Various changes may be made without departing from the spirit and scope of the invention. | Current fluid ejector maintenance techniques do not adequately deal with moveable debris particles present in the fluid supply manifold. Such moveable particles within the fluid supply manifold of a fluid ejector head can cause random ejection defects by clogging, restricting and/or blocking the channel inlets and/or filters present in the channel inlets, causing missed or misfired and/of misdirected drops. At least some of a plurality of fluid ejectors can be fired in a sequential pattern. Sequentially firing the fluid ejectors can move movable particles in the direction of the firing sequence. The moved movable particles can be deposited into non-operative areas within the fluid supply manifold, such as, for example, non-firing fluid ejection locations. The fluid ejectors can be fired in a sequential pattern within blocks of the fluid ejectors. For example, a fluid ejector head with 120 fluid ejectors can fire 1 out of every 20 fluid ejectors. | 1 |
BACKGROUND
[0001] 1. Field of the Invention
[0002] Embodiments of the invention generally relate to electronics. In particular, embodiments of the invention relate to analog integrated circuits.
[0003] 2. Description of the Related Art
[0004] Analog amplifiers are widely use in electronic devices. Applications include, but are not limited to: buffers, attenuators, gain amplifiers, current amplifiers, filters, drivers, interface circuits between digital and analog domains, and the like. One type of amplifier is known as an operational transconductance amplifier (OTA). An OTA receives a differential input voltage and generates an output current. OTAs are commonly used in, for example, variable frequency oscillators, filters, variable gain amplifiers, and the like.
[0005] It is desirable for an analog amplifier to have relatively good performance, to be inexpensive to manufacture, to be usable in a wide range of power supply voltages, to be able to swing relatively large output voltages, and the like. For example, in a mobile battery-powered application with a relatively low-voltage power supply, analog amplifiers preferably efficiently utilize the available supply voltage.
[0006] In the context of a switched-capacitor filter, an operational transconductance amplifier (OTA) is described by Rinaldo Castello, et al., in “ A 500- nA Sixth - Order Bandpass SC Filter ,” IEEE JOURNAL OF SOLID-STATE CIRCUITS, Vol. 25, No. 3, June 1990, pp. 669-676. However, the application of the foregoing amplifier appears to be prone to relatively severe mismatches for the drain-to-source voltages of the mirror transistors. For example, with reference to Castello, ibid, the drain-to-source voltages for the following three current mirrors: M 7 /M 9 , M 8 /M 11 and M 13 /M 15 all appear to be mismatched.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] The drawings and the associated description herein are provided to illustrate specific embodiments of the invention and are not intended to be limiting.
[0008] FIG. 1 is a schematic generally illustrating a current-mirror (symmetrical) operational transconductance amplifier with self-biased cascode current mirrors.
[0009] FIG. 2 is a schematic generally illustrating a folded-cascode operational transconductance amplifier with self-biased cascode current mirrors.
[0010] FIG. 3 is a schematic generally illustrating a folded-cascode operational transconductance amplifier with additional low-threshold voltage transistors.
DETAILED DESCRIPTION OF EMBODIMENTS
[0011] Circuit topologies are disclosed that provide an operational transconductance amplifier (OTA) with one or more self-biased cascode current mirrors. Applicable topologies include a current-mirror OTA and a folded-cascode OTA. An OTA is found in many analog circuits. Applications include, but are not limited to: buffers, attenuators, gain amplifiers, current amplifiers, filters, drivers, sensors, interface circuits between digital and analog domains, and the like.
[0012] One advantage of the self-biased cascode current mirror is that it saves extra bias voltages from having to be provided. This advantageously reduces power consumption, size, and cost. Although particular embodiments are described herein, other embodiments of the invention, including embodiments that do not provide all of the benefits and features set forth herein, will be apparent to those of ordinary skill in the art. For example, while the self-biased cascode current mirror is illustrated in the examples implemented in NMOS, the principles and advantages described herein are also applicable to PMOS.
[0013] FIG. 1 is a schematic generally illustrating a current-mirror (symmetrical) operational transconductance amplifier with self-biased cascode current mirror circuits. In the illustrated embodiment, all three of the cascode current mirror circuits are self biased. However, in an alternative embodiment, fewer than all of the cascode current mirror circuits are self biased.
[0014] In FIG. 1 , VAA and AGND indicates voltage references, e.g., a positive voltage for FAA and analog ground for AGND. Transistors MN 0 and MN 1 form a differential input circuit. Transistors MP 0 -MP 3 , MP 4 -MP 7 , and MN 2 -MN 5 form self-biased cascode current mirror circuits. A current reference I bias biases the differential input circuit. For example the current reference I bias can be embodied by a drain terminal of a transistor having a voltage-biased gate terminal. For the purposes of illustration, the transistors will be described as having the same size or width-to-length ratio (W/L). However, it will be understood that scaled devices can be used and that with respect to current-mirroring, mirrored currents typically scale in proportion with the scaling of the transistors.
[0015] In the illustrated examples, the cascode transistors MP 1 , MP 3 , MP 5 , MP 7 , MN 2 , and MN 4 have a lower threshold voltage than the mirror transistors MP 0 , MP 2 , MP 4 , MP 6 , MN 3 , and MN 5 . This permits the gate terminals of each of the transistors of the cascode current mirror circuits to be tied together and obviates the need for a biasing circuit specifically for the cascode transistors and avoids an undesirable offset as found in Castello's implementation.
[0016] Operation of the current-mirror operational transconductance amplifier will now be described. A gate terminal of transistor MN 1 is coupled to a non-inverting input V inp . A gate terminal of transistor MN 0 is coupled to an inverting input V inn . Source terminals of transistors MN 0 and MN 1 are coupled to each other and to the current reference I bias .
[0017] The operation of the self-biased cascode current mirror circuit of transistors MP 4 -MP 7 will now be described. The other self-biased cascode current mirror circuits (MP 0 -MP 3 and MN 2 -MN 5 ) operate in the same manner. Transistors MP 4 and MP 5 form a reference portion of the self-biased cascode current mirror circuit. Transistors MP 6 and MP 7 form a mirror portion of the self-biased cascode current mirror circuit. Transistors MP 5 and MP 7 are cascode transistors. Transistors MP 4 and MP 6 are mirror transistors.
[0018] The drain current of transistor MN 1 also flows through transistors MP 4 and MP 5 . The current establishes a gate-to-source voltage across transistor MP 4 , which is applied as a gate-to-source control voltage across transistor MP 6 so that the current of transistor MP 6 mirrors the current of transistor MP 4 . Due to the series connection, the current of transistor MP 7 is the same as the current of transistor MP 6 . The resulting current flowing out of the drain terminal of transistor MP 7 then mirrors the current flowing out of the drain terminal of transistor MP 5 and into the drain terminal of transistor MN 1 . It will be understood that transistors MP 6 and MP 7 can be scaled relative to transistors MP 4 and MP 5 , and that if scaled, the current will typically similarly scale. The use of the term “mirror” herein does not imply that the scaling is necessarily 1:1. The mirrored current from transistor MP 7 provides current to the output node V out .
[0019] The inequality expressed in Equation 1 should be satisfied to bias the self-biased cascode current mirror circuit in the desirable saturation region for analog operation.
[0000] (| V GS — MIRR |−|V GS — CASC |)=| V DS — MIRR |>|V DSAT — MIRR | Eq. 1
[0020] In Equation 1, V GS — CASC is the gate-to-source voltage for a cascode transistor (e.g., transistor MP 5 ); V GS — MIRR is the gate-to-source voltage for a mirror transistor (e.g., transistor MP 4 ); V DS — MIRR is the drain-to-source voltage for a mirror transistor; and V DSAT — MIRR is drain-to-source saturation voltage for a mirror transistor.
[0021] The self-biased cascode current mirror circuit of transistors MP 0 -MP 3 generates a mirror current flowing out of the drain terminal of transistor MP 1 that is a mirror of the current flowing into the drain terminal of transistor MN 0 . The mirrored current from the drain terminal of transistor MP 1 flows into the drain terminal of transistor MN 2 of the self-biased cascode current mirror circuit of transistors MN 2 -MN 5 . The mirrored current from transistor MP 1 flows through transistors MN 2 and MN 3 . The self-biased cascode current mirror circuit of transistors MN 2 -MN 5 generates a mirror current flowing into the drain terminal of transistor MN 4 and through transistors MN 4 and MN 5 . This mirror current sinks current from the output node V out .
[0022] FIGS. 2 and 3 are schematics generally illustrating a folded-cascode operational transconductance amplifier with self-biased cascode current mirrors. Transistors MN 9 and MN 10 form a differential input circuit. Transistor MN 15 forms a current source (sink) that biases the differential input circuit. Transistors MP 8 -MP 11 form fixed and variable current references. Transistors MN 11 -MN 14 form a self-biased cascode current mirror.
[0023] A gate terminal of transistor MN 15 is coupled to a bias voltage V bias1 . In the illustrated embodiment of FIG. 2 , gate terminals of transistors MP 9 and MP 11 are coupled to a bias voltage V bias2 , and gate terminals of transistors MP 8 and MP 10 are coupled to a bias voltage V bias3 . In an alternative embodiment illustrated in FIG. 3 , transistors MP 9 and MP 11 have a lower threshold voltage than transistors MP 8 and MP 10 , and the bias voltage V bias2 is not needed, further reducing the number of voltage biases used. In one embodiment, the self-biasing feature of the cascode current mirror circuit for the embodiment of FIG. 3 is optional, e.g., a conventional cascode current mirror circuit can be used. A source terminal of transistor MN 15 is coupled to a voltage reference (AGND). The drain terminal of transistor MN 15 is coupled to source terminals of transistors MN 9 and MN 10 of the differential input circuit.
[0024] A gate terminal of transistor MN 10 is coupled to an inverting input V inn , and a gate terminal of transistor MN 9 is coupled to a non-inverting input V inp .
[0025] A drain terminal of transistor MN 10 is coupled to a drain terminal of transistor MP 10 and to a source terminal of transistor MP 11 . A drain terminal of transistor MN 9 is coupled to a drain terminal of transistor MP 8 and to a source terminal of transistor MP 9 . Source terminals of transistors MP 8 and MP 10 are coupled to a voltage reference (VAA). A drain terminal of transistor MP 11 is coupled to an output node V out . A drain terminal of transistor MP 9 is coupled to the drain terminal of transistor MN 11 of the self-biased cascode current mirror circuit.
[0026] Transistors MN 11 and MN 13 of the self-biased cascode current mirror circuit have a lower-threshold voltage than transistors MN 12 and MN 14 . The drain terminal of transistor MN 11 is coupled to the gate terminals of transistors MN 11 -MN 14 . The source terminal of transistor MN 11 is coupled to the drain terminal of transistor MN 12 . The source terminals of transistors MN 12 and MN 14 are coupled to a voltage reference (AGND). The drain terminal of transistor MN 14 is coupled to the source terminal of transistor MN 13 . The drain terminal of transistor MN 13 is coupled to the output node V out .
[0027] The folded cascode OTA circuit generally operates as follows. For the purposes of explanation, current flow due to parasitic capacitance at high speeds is ignored. Transistors MP 8 and MP 10 generate relatively constant currents at their drain terminals. With respect to transistor MP 10 , a portion of the current from the drain terminal of transistor MP 10 flows through the drain terminal of transistor MN 10 and another portion flows through the source terminal of transistor MP 11 . The differential input voltage V inp , V inn determines how the current from transistor MP 10 is allocated between transistor MN 10 and transistor MP 11 . The current flowing from the drain terminal of transistor MP 11 flows into the output node V out .
[0028] Similarly, the current flowing from the drain terminal of transistor MP 9 flows into the drain terminal of transistor MN 11 . The same current flowing through transistor MN 11 flows through transistor MN 12 . The gate-to-source voltage of transistor MN 14 is the same as the gate-to-source voltage of transistor MN 12 , and the current through transistors MN 13 and MN 14 should then mirror the current flowing through transistors MN 11 and MN 12 , which in turn, mirror the current flowing through transistor MP 9 . The drain terminal of transistor MN 13 is coupled to the output node V out to sink current from that node.
[0029] Various embodiments have been described above. Although described with reference to these specific embodiments, the descriptions are intended to be illustrative and are not intended to be limiting. Various modifications and applications may occur to those skilled in the art without departing from the true spirit and scope of the invention as defined in the appended claims. | Apparatus and methods provide an operational transconductance amplifier (OTA) with one or more self-biased cascode current mirrors. Applicable topologies include a current-mirror OTA and a folded-cascode OTA. In one embodiment, the self-biasing cascode current mirror is an optional aspect of the folded-cascode OTA. The self-biasing can advantageous reduce the number of biasing circuits used, which can save chip area and cost. One embodiment includes an input differential pair of a current-mirror OTA. | 7 |
This application is a continuation of U.S. patent application Ser. No. 11/991,637 filed on Jul. 16, 2008 which is a national stage application under 35 U.S.C. §371 of PCT Application No. PCT/JP2006/317574 filed on Sep. 5, 2006 which claims priority to Japanese Patent Application No. 2005-261366 filed on Sep. 8, 2005, all of which are incorporated in their entirety herein by reference.
TECHNICAL FIELD
The present invention is related to a promoter for introducing a gene into lymphocytes or blood cells, and the application thereof.
BACKGROUND ART
There has been a demand for the establishment of a technique for gene therapy on lymphoid cells in order to treat various diseases targeting lymphoid cells, e.g., human immunodeficiency virus (HIV) infection. However, no satisfactory vector system for introducing a desired gene into lymphoid cells has been developed.
Herpesvirus (HHV) is a generic term referring to viruses of the family Herpesviridae. Both human herpesvirus 6 and 7 (HHV-6 and HHV-7) are double-stranded DNA viruses of the subfamily β Herpesviridae of the family Herpesviridae, which are responsible for exanthem subitum. (Yamanishi K. et al., “Identification of human herpesvirus 6 as a casual agent for exanthem subitum”, Lancet 1988; i: 1065-1067 and Tanaka K. et al., “Human herpesvirus 7: Another casual agent for roseola (exanthem subitum)”, J. pediatr., 1994; 125: 1-5) HHV-6 includes two strains, HHV-6A and HHV-6B. HHV-6 causes a viral infectious disease which often occurs during infancy and induces sudden high fever and exanthema before and after the reduction of fever. Its prognosis is generally good. HHV-7 infection tends to occur later than HHV-6 infection (Tanaka K. et al., “Seroepidemiological study of human herpesvirus-6 and -7 in children of different ages and detection of those two viruses in throat swabs by polymerase chain reaction”, Journal of Medical Virology, 1996; 48: 88-94). Therefore, exanthem subitum caused by HHV-7 is clinically experienced as second exanthem subitum. A seroepidemiological study of HHV-6 and HHV-7 demonstrated that most children become positive for antibodies for HHV-6 and HHV-7 before the age of two or three. It has been reported that the inapparent infection rate is 20 to 40%.
HHV-7 is a herpesvirus which was newly found by Frenkel et al. in 1990 when a cytopathic effect occurred during culturing of CD4 + T lymphoid cells of a healthy person's peripheral blood (Frankel N. et al., “Isolation of a new herpesvirus from human CD4 + T cells”, ProNAS USA, 87: 749-752, ProNAS USA, 87: 749-752, 1990). The virus was isolated from mononuclear cells of human peripheral blood. Both HHV-6 and -7 are CD4 + T lymphoid cell tropic viruses. HHV-7 infects the cell via a CD4 receptor on the cell. HHV-7 can grow only in human T lymphoid cells. Therefore, HHV-7 is a virus which can be used for gene modification of human T lymphoid cells.
The HHV-7 genome is double-stranded DNA of about 145 kbp. The whole base sequence has been determined by Nicholas et al. It is known that at least 101 genes are present on the genome (John N. et al., Journal of Virology, September 1996, 5975 to 5989).
However, with respect to these HHVs, no detailed analysis has been conducted so far regarding the promoter activity thereof. Moreover, what is lymphoid cell specific for the viruses was due to the interaction with receptors in the cells, and the life cycle in which the viruses can only be propagated in human T-lymphocytes.
In addition, it is believed that these viruses, particularly HHV-7 virus, have no adverse effect on healthy persons. If a gene containing an antigenic determinant of various viruses (e.g., mumps) is incorporated into the viral genome of HHV-7 and is expressed in HHV-7, HHV-7 is considered to be useful as a vaccine. However, when HHV-7 is used as a vaccine, it is not preferable that the genotype is changed as the virus is subcultured, in terms of quality control and quality assurance. Therefore, when the recombinant virus is used as a vaccine, it is necessary to stably supply a virus derived from a single recombinant genotype virus. For this purpose, a technique for producing a HHV-7 recombinant virus having a single genotype has been desired.
In addition, the mutual relationship between the HIV infection of a T lymphoid cell strain SupT1 cell and a T lymphoid cell tropic human herpesvirus (HHV-6A (U1102 strain), HHV-7 (MRK, MSO strains)) has been studied. The HHV-7 strain, which is bound by a CD4 receptor of cells, exhibits satisfactory growth in SupT1 cells. However, infection could not been established for SupT1/HIV cells. In contrast, it has been recognized that the HHV-6A strain infects HIV-persistent infection SupT1 (SupT1/HIV) cells and exhibits clear CPE (Masao Yamada et al., “HIV Jizokukansen SupT1 Saibo heno HHV-6 oyobi-7 Choufukukannsen no Kokoromi (Attempt for HHV-6 and -7 Superinfection to HIV Persistent Infection Sup-T1 Cell)”, Title No. 122, Titles and Abstracts of the 7th Annual Meeting of the Japanese Society for AIDS Research, 1993, Tokyo).
An ideal HIV vaccine can provide perfect and long-term protection from all types of HIV. On the other hand, conventional inactivated HIV vaccines have advantages and disadvantages, some of which will be described below. A method for producing a recombinant vaccine employs common techniques. However, since it is difficult to maintain immunogenicity (since immunogenicity is low), high antigenic load and frequent inoculation of an adjuvant are required. Safety is the greatest concern. A subunit vaccine containing either a native or recombinant subunit may be safe. However, such a subunit vaccine requires high antigen load and frequent vaccination with adjuvant, because of the use of a subunit and the low immunogenicity. Moreover, safety is the most important issue. Furthermore, subunit vaccines comprising either a native or a recombinant subunit may be safe, however, they are subjected to limitation due to low selectivity and low immunogenicity of the subunit, thereby they allow development of usable vaccines for treating an immune responsible cell such as HIV vaccines and the like.
[non-patent literature 1] Yamanishi K et al., “Identification of human herpesvirus 6 as a casual agent for exanthem subitum.” Lancet 1988; i: pp. 1065-1067 [non-patent literature 2] Tanaka K et al., “Human herpesvirus 7: Another casual agent for roseola (exanthem subitum)” J pediatr. 1994; 125: pp. 1-5 [non-patent literature 3] Tanaka-Taya K et al., “Seroepidemiological study of human herpesvirus-6 and -7 in children of different ages and detection of those two viruses in throat swabs by polymerase chain reaction” Journal of Medical Virology. 1996; 48: pp. 88-94 [non-patent literature 4] Frankel N et al., “Isolation of a new herpesvirus from human CD4+ T cells.” ProNAS USA 87:749-752, ProNAS USA 87:749-752, 1990 [non-patent literature 5] John N. et al., Journal of Virology, Sep. 1996, pp. 5975-5989 [non-patent literature 6] Masao Yamada et al., “HIV Jizokukansen SupT1 Saibo heno HHV-6 oyobi-7 Choufukukannsen no Kokoromi (Attempt for HHV-6 and -7 Superinfection to HIV Persistent Infection Sup-T1 Cell)”, Title No. 122, Titles and Abstracts of the 7th Annual Meeting of the Japanese Society for AIDS Research, 1993, Tokyo
DISCLOSURE OF THE INVENTION
Problem to be Solved by the Invention
It is an object of the present invention to provide a promoter which induces gene expression in an immune system cell or blood cell such as lymphoid cells, in a selective and potent manner.
Means for Solving the Problem
The above mentioned problems have been solved by the present invention by discovering that MIE promoter of HHV6, MIE promoter of HHV67, m and U95 promoter of HHV7 surprisingly induce specific expression in an immune responsible cell such as T lymphoid cell, or hemocyto-lineage cells.
In development of DNA vaccines, which are an attractive new technology, potent expression promoters are essential. To date, human cytomegalovirus (HCMV) immediate early (IE) promoter is widely used in DNA vaccines. This is due to the fact that HCMV IE promoters are believed to exhibit potent activity in a variety of cells in general. However, it is reported that the expression efficiency thereof is low in lymphoid lineage cells, and the phenomenon of inactivation due to methylation and the like is observed. Moreover, there are problems associated with a variety of restrictions which inhibit realization of the application of the HHV IE promoter on DNA vaccines.
HCMV is known to have a limited number of cells which it can infect, but is known to infect fibroblast cells and blood endothelial cells and the like. On the other hand, HHV-6 infects human infants and causes exanthema subitum or roseola infantum, and it is known that it proliferates well in human lymphocytes, in particular, T cells. The present inventors have elucidated in the present invention that major immediate early gene (MIE) of HHV-6, which belongs to the same β virus subgenus of the human herpesvirus genus, the same as HCMV, exhibits strong promoter activity. The present inventors have also elucidated that the MIE gene promoter is available for DNA vaccines. HHV-7 is also a CD4 + T lymphocyte directed virus, and the promoter thereof can be used to develop DNA vaccines, for example, to prevent or treat a disease related to CD4 + T lymphocytes. The present inventors have elucidated in the present invention the utility of HHV 7 MIE promoter and HHV 7 U95 promoter, and thus also elucidated that these promoters can be used for DNA vaccines.
Therefore, the present invention provides the following:
(1) An MIE promoter of HHV6B.
(2) The promoter according to item 1, which comprises at least eight contiguous nucleotides of the sequence set forth in SEQ ID NO: 1.
(3) The promoter according to item 1, which comprises at least the R3 region of the sequence set forth in SEQ ID NO: 1 or a functional variant thereof.
(4) The promoter according to item 1, which comprises at least the sequence of −574 to −427 (SEQ ID NO: 13) from the transcription initiation point of the SEQ ID NO: 1.
(5) The promoter according to item 1, which comprises at least the sequence of −1051 to −427 (SEQ ID NO: 14) from the transcription initiation point of SEQ ID NO: 1.
(6) The promoter according to item 1, which comprises a motif of NF-κB and a motif of AP-1.
(7) The promoter according to item 1, which comprises the sequence set forth in SEQ ID NO: 1.
(8) The promoter according to item 1, wherein the promoter comprises: (a) a polynucleotide having the base sequence set forth in SEQ ID NO: 1, or the base sequence corresponding thereto or a fragment sequence thereof;
(b) a polynucleotide of an allelic variant of the base sequence set forth in SEQ ID NO: 1 or the base sequence corresponding thereto or a fragment sequence thereof;
(c) a polynucleotide which hybridizes a polynucleotide of any of (a) or (b) and has a biological activity thereof; or
(d) a polynucleotide which consists of the base sequence of any of (a) to (c) or a complement sequence thereof with at least 70% identity, and has a biological activity thereof.
(9) The promoter according to item 1, which is at least 10 contiguous nucleotides in length.
(10) The promoter according to item 8, wherein the biological activity is the promoter activity.
(11) A nucleic acid construct comprising the promoter according to item 1.
(12) The nucleic acid construct according to Item 11, which comprises a sequence encoding a foreign gene which is not related to the promoter but is operatively linked to the sequence of the promoter.
(13) The nucleic acid construct according to item 12, wherein the foreign gene encodes an RNAi molecule, a drug, a recessive gene to be deleted, or a selective marker.
(14) The nucleic acid construct according to item 13, wherein the selective marker allows selection in a medium of a host in which the nucleic acid construct is introduced.
(15) The nucleic acid construct according to item 13, wherein the selective marker allows visual selection in a host in which the nucleic acid construct is introduced.
(16) The nucleic acid construct according to item 13, wherein the selective marker comprises hypoxanthine guanine phosphoribosyl transferase (hprt) or a fluorescent marker selected from the group consisting of green fluorescent protein (GFP), cyan fluorescent protein (CFP), yellow fluorescent protein (YFP) and red fluorescent protein (dsRed).
(17) The nucleic acid construct according to item 13, wherein the selective marker does not substantially exhibit toxicity against the host in which the nucleic acid construct is introduced.
(18) The nucleic acid construct according to item 13, wherein the recessive gene to be deleted is selected from the group consisting of ADA gene, PNP gene, γ c chain gene, TAP gene, MHC II gene, X-linked WASP, CD40 ligand, PI3K-like gene and DNA helicase.
(19) The nucleic acid construct according to item 13, wherein the drug is selected from the group consisting of a cytokine, a chemokine, a growth factor, a protein hormone, and a peptide hormone (e.g. interferon (IFN)-α, IFN-γ, interleukin [IL]-2, IL-12, granulocyte colony stimulating factor [G-CSF], granulocyte macrophage colony stimulating factor [GM-CSF]).
(20) The nucleic acid construct according to item 12, wherein the promoter induces specific expression of the foreign gene in a hemocyto-lineage cell, in particular, in a T cell.
(21) An expression vector comprising the nucleic acid construct according to item 11.
(22) A cell comprising the nucleic acid construct according to item 11.
(23) The cell according to item 22, wherein the cell is heterogenous to the promoter sequence.
(24) A tissue comprising the nucleic acid construct according to item 11.
(25) An organ comprising the nucleic acid construct according to item 11.
(26) An organism comprising the nucleic acid construct according to item 11.
(27) A pharmaceutical composition comprising the promoter according to item 1 and a sequence encoding an antigen.
(28) The pharmaceutical composition according to item 27, which is a DNA vaccine.
(29) A pharmaceutical composition for treating a disease, disorder or condition in which a lymphocyte-specific treatment is desired, which comprises the promoter according to item 1, and a nucleic acid sequence for the treatment.
(30) The pharmaceutical composition according to item 29, wherein the nucleic acid sequence for the treatment comprises a sequence selected from the group consisting of those encoding cytokines, chemokines, growth factors, protein hormones, peptide hormones, ribozymes and RNAis
(HIV-1 gp41:
(SEQ ID NO: 33)
AATAAGACAGGGCTTGGAAAGACACTTTCCAAGCCCTGTCTTATTTTT/
HIV-1 tat:
(SEQ ID NO: 34)
AAGCATCCAGGAAGTCAGCCTACAAGGCTGACTTCCTGGATGCTTTTT/
HTLV-1 tax:
(SEQ ID NO: 35)
GAACATTGGTGAGGAAGGCACAGCCTTCCTCACCAATGTTCTTTTT).
(31) A method for expressing a protein in a lymphocyte specific manner, comprising the steps of:
A) preparing a nucleic acid construct in which the promoter according to item 1 is operatively linked to a nucleic acid sequence encoding the protein; and
B) placing the nucleic acid construct under a condition in which the promoter induces the expression of the nucleic acid sequence encoding the protein.
(32) A kit for expressing a protein in a lymphocyte specific manner, comprising:
A) a nucleic acid construct in which the promoter according to item 1 is operatively linked to a nucleic acid sequence encoding the protein; and
B) means for placing the nucleic acid construct under a condition in which the promoter induces the expression of the nucleic acid sequence encoding the protein.
(33) A kit for expressing a protein in a lymphocyte specific manner, comprising:
A) the promoter according to item 1; and
B) means for producing a nucleic acid construct in which the promoter is linked to a nucleic acid sequence encoding the protein.
(34) A method for treating or preventing a disease, disorder or condition which requires the expression of a protein in a lymphocyte specific manner, comprising the steps of:
A) producing a nucleic acid construct in which the promoter according to item 1 is linked to a nucleic acid sequence encoding the protein; and
B) placing the nucleic acid construct under a condition in which the promoter induces the expression of the nucleic acid sequence encoding the protein.
(35) A kit for treating or preventing a disease, disorder or condition which requires the expression of a protein in a lymphocyte specific manner, comprising:
A) a nucleic acid construct in which the promoter according to item 1 is linked to a nucleic acid sequence encoding the protein; and
B) means for placing the nucleic acid construct under a condition in which the promoter induces the expression of the nucleic acid sequence encoding the protein.
(36) A kit for treating or preventing a disease, disorder or condition which requires the expression of a protein in a lymphocyte specific manner, comprising:
A) the promoter according to item 1; and
B) means for producing a nucleic acid construct in which the promoter is linked to a nucleic acid sequence encoding the protein.
(37) A method for producing a protein, comprising the steps of:
A) preparing a nucleic acid construct in which the promoter according to item 1 is linked to a nucleic acid sequence encoding the protein; and
B) placing the nucleic acid construct under a condition in which the promoter induces the expression of the nucleic acid sequence encoding the protein.
(38) A kit for producing a protein, comprising:
A) a nucleic acid construct in which the promoter according to item 1 is linked to a nucleic acid sequence encoding the protein; and
B) means for placing the nucleic acid construct under a condition in which the promoter induces the expression of the nucleic acid sequence encoding the protein.
(39) A kit for producing a protein, comprising:
A) the promoter according to item 1; and
B) means for producing a nucleic acid construct in which the promoter is linked to a nucleic acid sequence encoding the protein.
(40) Use of the promoter according to item 1, for manufacture of a pharmaceutical composition for treating or preventing a disease, disorder or condition which requires the expression of a protein in a lymphocyte specific manner.
(41) An MIE promoter of HHV7.
(42) The promoter according to item 41, which comprises at least eight contiguous nucleotides of the sequence set forth in SEQ ID NO: 2.
(43) The promoter according to item 41, which comprises at least the R2 region of the sequence set forth in SEQ ID NO: 2 or a functional variant thereof.
(44) The promoter according to item 41, which comprises at least the sequence of +22 to −233 of the SEQ ID NO: 2.
(45) The promoter according to item 41, which comprises at least the sequence of +22 to −388 of the SEQ ID NO: 2.
(46) The promoter according to item 41, which comprises a motif of NF-κB present in the R2 region.
(47) The promoter according to item 41, which comprises the sequence set forth in SEQ ID NO: 15.
(48) The promoter according to item 41, wherein the promoter comprises:
(a) a polynucleotide having the base sequence set forth in SEQ ID NO. 2, or a base sequence corresponding thereto or a fragment sequence thereof;
(b) a polynucleotide of an allelic variant of the base sequence set forth in SEQ ID NO. 2 or the base sequence corresponding thereto or a fragment sequence thereof;
(c) a polynucleotide which hybridizes a polynucleotide of any of (a) or (b) and has a biological activity thereof; or
(d) a polynucleotide which consists of the base sequence of any of (a) to (c) or a complement sequence thereof with at least 70% identity, and has a biological activity thereof.
(49) The promoter according to item 41, which is at least 10 contiguous nucleotides in length.
(50) The promoter according to item 48, wherein the biological activity is the promoter activity.
(51) A nucleic acid construct comprising the promoter according to item 41.
(52) The nucleic acid construct according to Item 51, which comprises a sequence encoding a foreign gene which is not related to the promoter but is operatively linked to the sequence of the promoter.
(53) The nucleic acid construct according to item 52, wherein the foreign gene encodes an RNAi molecule, a drug, a recessive gene to be deleted, or a selective marker.
(54) The nucleic acid construct according to item 53, wherein the selective marker allows selection in a medium of a host in which the nucleic acid construct is introduced.
(55) The nucleic acid construct according to item 53, wherein the selective marker allows visual selection in a host in which the nucleic acid construct is introduced.
(56) The nucleic acid construct according to item 53, wherein the selective marker comprises hypoxanthine guanine phosphoribosyl transferase (hprt) or a fluorescent marker selected from the group consisting of green fluorescent protein (GFP), cyan fluorescent protein (CFP), yellow fluorescent protein (YFP) and red fluorescent protein (dsRed).
(57) The nucleic acid construct according to item 53, wherein the selective marker does not substantially exhibit toxicity against the host in which the nucleic acid construct is introduced.
(58) The nucleic acid construct according to item 53, wherein the recessive gene to be deleted is selected from the group consisting of ADA gene, PNP gene, γ c chain gene, TAP gene, MHC II gene, X-linked WASP, CD40 ligand, PI3K-like gene and DNA helicase.
(59) The nucleic acid construct according to item 53, wherein the drug is selected from the group consisting of a cytokine, a chemokine, a growth factor, a protein hormone, and a peptide hormone (IFN-α, IFN-γ, IL-2, IL-12, G-CSF, GM-CSF).
(60) The nucleic acid construct according to item 52, wherein the promoter induces specific expression of the foreign gene in a hemocyto-lineage cell, in particular, in a T cell.
(61) An expression vector comprising the nucleic acid construct according to item 51.
(62) A cell comprising the nucleic acid construct according to item 51.
(63) The cell according to item 62, wherein the cell is heterogenous to the promoter sequence.
(64) A tissue comprising the nucleic acid construct according to item 51.
(65) An organ comprising the nucleic acid construct according to item 51.
(66) An organism comprising the nucleic acid construct according to item 51.
(67) A pharmaceutical composition comprising the promoter according to item 41 and a sequence encoding an antigen.
(68) The pharmaceutical composition according to item 67, which is a DNA vaccine.
(69) A pharmaceutical composition for treating a disease, disorder or condition in which a lymphocyte-specific treatment is desired, which comprises the promoter according to item 41, and a nucleic acid sequence for the treatment.
(70) The pharmaceutical composition according to item 69, wherein the nucleic acid sequence for the treatment comprises a sequence selected from the group consisting of those encoding cytokines, chemokines, growth factors, protein hormones, peptide hormones, ribozymes and RNAis
(HIV-1 gp41:
(SEQ ID NO: 33)
AATAAGACAGGGCTTGGAAAGACACTTTCCAAGCCCTGTCTTATTTTT/
HIV-1 tat:
(SEQ ID NO: 34)
AAGCATCCAGGAAGTCAGCCTACAAGGCTGACTTCCTGGATGCTTTTT/
HTLV-1 tax:
(SEQ ID NO: 35)
GAACATTGGTGAGGAAGGCACAGCCTTCCTCACCAATGTTCTTTTT).
(71) A method for expressing a protein in a lymphocyte specific manner, comprising the steps of:
A) preparing a nucleic acid construct in which the promoter according to item 41 is operatively linked to a nucleic acid sequence encoding the protein; and
B) placing the nucleic acid construct under a condition in which the promoter induces the expression of the nucleic acid sequence encoding the protein.
(72) A kit for expressing a protein in a lymphocyte specific manner, comprising:
A) a nucleic acid construct in which the promoter according to item 41 is operatively linked to a nucleic acid sequence encoding the protein; and
B) means for placing the nucleic acid construct under a condition in which the promoter induces the expression of the nucleic acid sequence encoding the protein.
(73) A kit for expressing a protein in a lymphocyte specific manner, comprising:
A) the promoter according to item 41; and
B) means for producing a nucleic acid construct in which the promoter is linked to a nucleic acid sequence encoding the protein.
(74) A method for treating or preventing a disease, disorder or condition which requires the expression of a protein in a lymphocyte specific manner, comprising the steps of:
A) producing a nucleic acid construct in which the promoter according to item 41 is linked to a nucleic acid sequence encoding the protein; and
B) placing the nucleic acid construct under a condition in which the promoter induces the expression of the nucleic acid sequence encoding the protein.
(75) A kit for treating or preventing a disease, disorder or condition which requires the expression of a protein in a lymphocyte specific manner, comprising:
A) a nucleic acid construct in which the promoter according to item 41 is linked to a nucleic acid sequence encoding the protein; and
B) means for placing the nucleic acid construct under a condition in which the promoter induces the expression of the nucleic acid sequence encoding the protein.
(76) A kit for treating or preventing a disease, disorder or condition which requires the expression of a protein in a lymphocyte specific manner, comprising:
A) the promoter according to item 41; and
B) means for producing a nucleic acid construct in which the promoter is linked to a nucleic acid sequence encoding the protein.
(77) A method for producing a protein, comprising the steps of:
A) preparing a nucleic acid construct in which the promoter according to item 41 is linked to a nucleic acid sequence encoding the protein; and
B) placing the nucleic acid construct under a condition in which the promoter induces the expression of the nucleic acid sequence encoding the protein.
(78) A kit for producing a protein, comprising:
A) a nucleic acid construct in which the promoter according to item 41 is linked to a nucleic acid sequence encoding the protein; and
B) means for placing the nucleic acid construct under a condition in which the promoter induces the expression of the nucleic acid sequence encoding the protein.
(79) A kit for producing a protein, comprising:
A) the promoter according to item 41; and
B) means for producing a nucleic acid construct in which the promoter is linked to a nucleic acid sequence encoding the protein.
(80) Use of the promoter according to item 41, for manufacture of a pharmaceutical composition for treating or preventing a disease, disorder or condition which requires the expression of a protein in a lymphocyte specific manner.
(81) A U95 promoter of HHV7.
(82) The promoter according to item 81, which comprises at least eight contiguous nucleotides of the sequence set forth in SEQ ID NO: 12.
(83) The promoter according to item 81, which comprises at least the R2 region of the sequence set forth in SEQ ID NO: 12 or a functional variant thereof.
(84) The promoter according to item 81, which comprises at least the sequence of +16 to −233 of the SEQ ID NO: 12.
(85) The promoter according to item 81, which comprises at least the sequence of +16 to −379 of the SEQ ID NO: 12.
(86) The promoter according to item 81, which comprises a motif of NF-κB present in the R2 region.
(87) The promoter according to item 81, which comprises the sequence set forth in SEQ ID NO: 16.
(88) The promoter according to item 81, wherein the promoter comprises:
(a) a polynucleotide having the base sequence set forth in SEQ ID NO. 12, or the base sequence corresponding thereto or a fragment sequence thereof;
(b) a polynucleotide of an allelic variant of the base sequence set forth in SEQ ID NO. 12 or the base sequence corresponding thereto or a fragment sequence thereof;
(c) a polynucleotide which hybridizes a polynucleotide of any of (a) or (b) and has a biological activity thereof; or
(d) a polynucleotide which consists of the base sequence of any of (a) to (c) or a complement sequence thereof with at least 70% identity, and has a biological activity thereof.
(89) The promoter according to item 81, which is at least 10 contiguous nucleotides in length.
(90) The promoter according to item 88, wherein the biological activity is the promoter activity.
(91) A nucleic acid construct comprising the promoter according to item 81.
(92) The nucleic acid construct according to Item 91, which comprises a sequence encoding a foreign gene which is not related to the promoter but is operatively linked to the sequence of the promoter.
(93) The nucleic acid construct according to item 92, wherein the foreign gene encodes an RNAi molecule, a drug, a recessive gene to be deleted, or a selective marker.
(94) The nucleic acid construct according to item 93, wherein the selective marker allows selection in a medium of a host in which the nucleic acid construct is introduced.
(95) The nucleic acid construct according to item 93, wherein the selective marker allows visual selection in a host in which the nucleic acid construct is introduced.
(96) The nucleic acid construct according to item 93, wherein the selective marker comprises hypoxanthine guanine phosphoribosyl transferase (hprt) or a fluorescent marker selected from the group consisting of green fluorescent protein (GFP), cyan fluorescent protein (CFP), yellow fluorescent protein (YFP) and red fluorescent protein (dsRed).
(97) The nucleic acid construct according to item 93, wherein the selective marker does not substantially exhibit toxicity against the host in which the nucleic acid construct is introduced.
(98) The nucleic acid construct according to item 93, wherein the recessive gene to be deleted is selected from the group consisting of ADA gene, PNP gene, γ c chain gene, TAP gene, MHC II gene, X-linked WASP, CD40 ligand, PI3K-like gene and DNA helicase.
(99) The nucleic acid construct according to item 93, wherein the drug is selected from the group consisting of a cytokine, a chemokine, a growth factor, a protein hormone, and a peptide hormone (IFN-α, IFN-γ, IL-2, IL-12, G-CSF, GM-CSF).
(100) The nucleic acid construct according to item 92, wherein the promoter induces specific expression of the foreign gene in a hemocyto-lineage cell, in particular, in a T cell.
(101) An expression vector comprising the nucleic acid construct according to item 91.
(102) A cell comprising the nucleic acid construct according to item 91.
(103) The cell according to item 102, wherein the cell is heterogenous to the promoter sequence.
(104) A tissue comprising the nucleic acid construct according to item 91.
(105) An organ comprising the nucleic acid construct according to item 91.
(106) An organism comprising the nucleic acid construct according to item 91.
(107) A pharmaceutical composition comprising the promoter according to item 81 and a sequence encoding an antigen.
(108) The pharmaceutical composition according to item 107, which is a DNA vaccine.
(109) A pharmaceutical composition for treating a disease, disorder or condition in which a lymphocyte-specific treatment is desired, which comprises the promoter according to item 81, and a nucleic acid sequence for the treatment.
(110) The pharmaceutical composition according to item 109, wherein the nucleic acid sequence for the treatment comprises a sequence selected from the group consisting of those encoding cytokines, chemokines, growth factors, protein hormones, peptide hormones, ribozymes and RNAis
(HIV-1 gp41:
(SEQ ID NO: 33)
AATAAGACAGGGCTTGGAAAGACACTTTCCAAGCCCTGTCTTATTTTT/
HIV-1 tat:
(SEQ ID NO: 34)
AAGCATCCAGGAAGTCAGCCTACAAGGCTGACTTCCTGGATGCTTTTT/
HTLV-1 tax:
(SEQ ID NO: 35)
GAACATTGGTGAGGAAGGCACAGCCTTCCTCACCAATGTTCTTTTT).
(111) A method for expressing a protein in a lymphocyte specific manner, comprising the steps of:
A) preparing a nucleic acid construct in which the promoter according to item 81 is operatively linked to a nucleic acid sequence encoding the protein; and
B) placing the nucleic acid construct under a condition in which the promoter induces the expression of the nucleic acid sequence encoding the protein.
(112) A kit for expressing a protein in a lymphocyte specific manner, comprising:
A) a nucleic acid construct in which the promoter according to item 81 is operatively linked to a nucleic acid sequence encoding the protein; and
B) means for placing the nucleic acid construct under a condition in which the promoter induces the expression of the nucleic acid sequence encoding the protein.
(113) A kit for expressing a protein in a lymphocyte specific manner, comprising:
A) the promoter according to item 81; and
B) means for producing a nucleic acid construct in which the promoter is linked to a nucleic acid sequence encoding the protein.
(114) A method for treating or preventing a disease, disorder or condition which requires the expression of a protein in a lymphocyte specific manner, comprising the steps of:
A) producing a nucleic acid construct in which the promoter according to item 81 is linked to a nucleic acid sequence encoding the protein; and
B) placing the nucleic acid construct under a condition in which the promoter induces the expression of the nucleic acid sequence encoding the protein.
(115) A kit for treating or preventing a disease, disorder or condition which requires the expression of a protein in a lymphocyte specific manner, comprising:
A) a nucleic acid construct in which the promoter according to item 81 is linked to a nucleic acid sequence encoding the protein; and
B) means for placing the nucleic acid construct under a condition in which the promoter induces the expression of the nucleic acid sequence encoding the protein.
(116) A kit for treating or preventing a disease, disorder or condition which requires the expression of a protein in a lymphocyte specific manner, comprising:
A) the promoter according to item 81; and
B) means for producing a nucleic acid construct in which the promoter is linked to a nucleic acid sequence encoding the protein.
(117) A method for producing a protein, comprising the steps of:
A) preparing a nucleic acid construct in which the promoter according to item 81 is linked to a nucleic acid sequence encoding the protein; and
B) placing the nucleic acid construct under a condition in which the promoter induces the expression of the nucleic acid sequence encoding the protein.
(118) A kit for producing a protein, comprising:
A) a nucleic acid construct in which the promoter according to item 81 is linked to a nucleic acid sequence encoding the protein; and
B) means for placing the nucleic acid construct under a condition in which the promoter induces the expression of the nucleic acid sequence encoding the protein.
(119) A kit for producing a protein, comprising:
A) the promoter according to item 81; and
B) means for producing a nucleic acid construct in which the promoter is linked to a nucleic acid sequence encoding the protein.
(120) Use of the promoter according to item 81, for manufacture of a pharmaceutical composition for treating or preventing a disease, disorder or condition which requires the expression of a protein in a lymphocyte specific manner.
Hereinafter, preferable embodiments of the present invention are presented. It should be understood that those skilled in the art would appropriately practice the embodiments thereof based on the description of the present invention in view of the well known and routinely used technology in the art, and the functions and effects attained by the present invention should be readily understood.
EFFECTS OF THE INVENTION
The present invention provides promoters which selectively induce the expression of a protein in a cell of the immune system such as T lymphocytes. The promoters of the present invention are used to provide a method and medicament for effectively preventing or treating immunological disease such as innate immune deficiency syndrome and the like. The present invention also provides a technology in order to efficiently conduct gene therapy.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 depicts a comparison of promoter activities in adhesive cells. The x-axis aligns a variety of promoters, and the promoter activities of the Vero cell, the HEL cell, the L929 cell, the 293 cell and the 373 cell are shown using Log(RLU)/β-gal with logarithmic reference.
FIG. 2 depicts the comparison of promoter activities in lymphocytes. The x-axis aligns a variety of promoters, and the promoter activities of the THP-1 cell, the SupT1 cell and the U937 cell are shown using Log(RLU)/β-gal with logarithmic reference.
FIG. 3 depicts the promoter activity of the HHV-6 MIE region in the case of stimulating a cell with TPA (Vero cell). On the x-axis, a variety of promoters are aligned, and the activity of a promoter with and without TPA is shown using Log(RLU)/β-gal in a logarithmic manner.
FIG. 4 depicts promoter activity of the HHV-6 MIE region (L929 cell) when the cell has been stimulated with TPO. On the x-axis, a variety of promoters are aligned, and the promoter activity in the presence or absence of TPA with respect to the respective promoters is depicted using Log(RLU)/β-gal in a logarithmic manner.
FIG. 5 depicts illustrations of a variety of deletion variants in a promoter region of the HHV6B. The upper panel shows the promoter region, and a variety of motifs in the promoter regions.
FIG. 6 depicts a measurement system for promoter activity.
FIG. 7 depicts the promoter activity (relative luciferase activity) with illustrations of a variety of deletion variants in the promoter region in the HHV6B.
FIG. 8 depicts illustrations of the immediate early (IE) gene relating to the promoter region of the HHV7 and the promoter thereof. The left column shows, from the top, 7MIE promoter (−493), 7MIE promoter (−388), and 7MIE promoter (−233), and the right column shows, from the top, 7U95 promoter (−484), 7U95 promoter (−379), and 7U95 promoter (−304).
FIG. 9 depicts the activity of the IE promoter of the HHV7 in a lymphocytic cell line. The upper left graph shows Jurkat cells, the upper right graph shows Molt-3 cells, the lower left graph shows SupT1 cells, and the lower right graph shows SAS-413 cells. Each graph shows, from the left, CMVP, 6MIEP, 6U95P, 7MIE (−493), 7U95 and P (−484), respectively.
FIG. 10 depicts the effects of R2 deletion on promoter activity. The upper left graph shows Jurkat cells, the upper right graph shows Molt-3 cells, the lower left graph shows SupT1 cells, and the lower right graph shows SAS-413 cells. The graphs show from the left, 7MIE promoter (−493), 7MIE promoter (−388), 7MIE promoter (−233), 7U95 promoter (−484), 7U95 promoter (−379) and 7U95 promoter (−304).
FIG. 11 depicts the promoter activity in a peripheral blood monocytic cell (PBMC). It shows lineage 1, lineage 2 and lineage 3, in the upper left, upper right and lower panels, respectively.
BRIEF DESCRIPTION OF SEQUENCE LISTING
SEQ ID NO: 1 is the sequence of HHV6B MIE promoter.
SEQ ID NO: 2 is the sequence of HHV7 MIE promoter.
SEQ ID NO: 3 is the sequence of HHV6A MIE promoter.
SEQ ID NO: 4 is the sequence of HHV6B R3 region.
SEQ ID NO: 5 is the sequence of 20u used in Example 1.
SEQ ID NO: 6 is the sequence of 9u used in Example 1.
SEQ ID NO: 7 is the sequence of MIE used in Example 1.
SEQ ID NO: 8 is the sequence of U95 used in Example 1.
SEQ ID NO: 9 is the sequence of CMV used in Example 1.
SEQ ID NO: 10 is the sequence of MIE/3K used in Example 1.
SEQ ID NO: 11 is the sequence of U95/3K used in Example 1.
SEQ ID NO: 12 is the sequence of HHV7 U95 promoter SEQ ID NO: 13 is the sequence of −574 to −427 from the transcription initiation site of HHV6B MIE.
SEQ ID NO: 14 is the sequence of −1051 to −427 from the transcription initiation site of HHV6B MIE.
SEQ ID NO: 15 is the sequence of +22 to −493 from the transcription initiation site of HHV7 MIE.
SEQ ID NO: 16 is the sequence of +16 to −484 from the transcription initiation site of HHV7 MIE.
SEQ ID NO: 17 is the sequence of 9u-d2-7 used in Example 1.
SEQ ID NO: 18 is the sequence of 9u-d1-4 used in Example 1.
SEQ ID NO: 19 is the sequence of 9u-d1-5 used in Example 1.
SEQ ID NO: 20 is the sequence of 9u-d1-7 used in Example 1.
SEQ ID NO: 21 is the sequence of 9u-d3-7 used in Example 1.
SEQ ID NO: 22 is the sequence of 9u-d5 used in Example 1.
SEQ ID NO: 23 is the sequence of 9u-d6 used in Example 1.
SEQ ID NO: 24 is the sequence of 9u-d7 used in Example 1.
SEQ ID NO: 25 is the sequence of 9u-d8 used in Example 1.
SEQ ID NO: 26 is the sequence of 7MIEP (−493) used in Example 2.
SEQ ID NO: 27 is the sequence of 7MIEP (−388) used in Example 2.
SEQ ID NO: 28 is the sequence of 7MIEP (−233) used in Example 2.
SEQ ID NO: 29 is the sequence of 7U95P (−484) used in Example 2.
SEQ ID NO: 30 is the sequence of 7U95P (−379) used in Example 2.
SEQ ID NO: 31 is the sequence of 7U95P (−304) used in Example 2.
SEQ ID NO: 32 is the sequence of pGL3 Basic used in Example 2.
SEQ ID NO: 33 is an example of RNAi of HIV-1 gp41.
SEQ ID NO: 34 is an example of RNAi of HIV-1 tat.
SEQ ID NO: 35 is an example of RNAi of HIV-1 tax.
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, the present invention will be described. It should be understood throughout the present specification that articles for singular forms (e.g., “a”, “an”, “the”, etc. in English, and articles, adjectives, etc. in other languages) include plural referents unless the context clearly dictates otherwise. It should be also understood that the terms as used herein have definitions typically used in the art unless otherwise mentioned. Accordingly, unless otherwise defined, all terminology and technical terms used herein will have the same meanings as those generally understood by those skilled in the art belonging to the filed of the present invention. If there is contradiction, the present specification (including the definition) takes precedence.
DEFINITION OF TERMS
The definitions of terms used herein are described below.
As used herein the term “HHV” refers to a human herpes virus, of which there are types 1, 2, 3, 4, 5, 6, 7, 8 and the like.
As used herein, the term “herpesvirus” includes all of HHV-6A, HHV-6B, and HHV-7, and both their wild-types and recombinant types unless otherwise mentioned. As used herein, the term “HHV-6 (human herpes virus 6)” includes HHV-6A and HHV-6B, and both their wild-types and recombinant types unless otherwise mentioned. HHV6 belongs to the β subgenus as cytomegalovirus HHV-5, and HHV6B is a causative virus of exanthema subitum, and it is said that most Japanese will have been infected therewith by the age of two years old. As used herein, the term “HHV-7 (human herpes virus 7)” refers to any herpes virus belonging to this type of herpes virus. HHV7 is also said to be a causative body of exanthema subitum, however, in comparison to HHV6B, the occurrence thereof is lower, and the age where the patients are infected is older. As with HHV6, HHV7 belongs to the β subgenus, and it is also said that it is believed to infect CD4 + cells, and thus cause the onset of pityriasis rosea Gibert, and it is also said that most Japanese will have been infected therewith by the age of two years old.
As used herein, the term “wild strain” in relation to herpesvirus refers to a herpesvirus strain which is not artificially modified and is isolated from nature. An example of a wild strain includes, but is not limited to, strain J1.
As used herein, the term “wild strain” in relation to HHV-6A refers to a HHV-6A strain which is not artificially modified and is isolated from nature. An example of a wild strain includes, but is not limited to, strain U1102.
As used herein, the term “mutant strain” refers to a herpesvirus strain which has a mutation due to mutagenesis, multiple subculturings or the like. Mutagenesis of a herpesvirus strain may be either random mutagenesis or site-specific mutagenesis.
As used herein, the term “wild strain” in relation to HHV-6B refers to a HHV-6B strain which is not artificially modified and is isolated from nature. An example of a wild strain includes, but is not limited to, strain HST.
The terms “protein”, “polypeptide”, “oligopeptide” and “peptide” as used herein have the same meaning and refer to an amino acid polymer having any length.
The terms “polynucleotide”, “oligonucleotide”, and “nucleic acid” as used herein have the same meaning and refer to a nucleotide polymer having any length. Unless otherwise indicated, a particular nucleic acid sequence also implicitly encompasses conservatively-modified variants thereof (e.g. degenerate codon substitutions) and complementary sequences as well as the sequence explicitly indicated. Specifically, degenerate codon substitutions may be produced by generating sequences in which the third position of one or more selected (or all) codons is substituted with mixed-base and/or deoxyinosine residues (Batzer et al., Nucleic Acid Res. 19:5081 (1991); Ohtsuka et al., J. Biol. Chem. 260:2605-2608 (1985); Rossolini et al., Mol. Cell. Probes 8:91-98 (1994)).
As used herein, the term “gene” refers to an element defining a genetic trait. A gene is typically arranged in a given sequence on a chromosome. A gene which defines the primary structure of a protein is called a structural gene. A gene which regulates the expression of a structural gene is called a regulatory gene. As used herein, “gene” may refer to “polynucleotide”, “oligonucleotide”, “nucleic acid”, and “nucleic acid molecule” and/or “protein”, “polypeptide”, “oligopeptide” and “peptide”. As used herein, the term “open reading frame” or “ORF” in relation to a gene, refers to a reading frame which is one of three frames obtained by sectioning the base sequence of a gene at intervals of three bases, and has a start codon and a certain length curtailed by the appearance of a stop codon, and has the possibility of actually coding a protein. The entire base sequence of the genome of herpesvirus has been determined, identifying at least 101 genes. Each of the genes is known to have an open reading frame (ORF).
As used herein, the term “RNAi” is an abbreviation of RNA interference and refers to a phenomenon where an agent for causing RNAi, such as double-stranded RNA (also called dsRNA), is introduced into cells and mRNA homologous thereto is specifically degraded, so that the synthesis of gene products is suppressed, and techniques using the phenomenon. As used herein, RNAi may have the same meaning as that of an agent which causes RNAi.
As used herein, the term “an agent causing RNAi” refers to any agent capable of causing RNAi. As used herein, “an agent causing RNAi of a gene” indicates that the agent causes RNAi relating to the gene and that the effect of RNAi is successfully achieved (e.g., suppression of expression of the gene, and the like). Examples of such an agent causing RNAi include, but are not limited to, a sequence having at least about 70% homology with the nucleic acid sequence of a target gene or a sequence hybridizable thereto under stringent conditions, and RNA containing a double-stranded portion having a length of at least 10 nucleotides or variants thereof. Here, this agent may be preferably DNA containing a 3′ protruding end, and more preferably the 3′ protruding end has a length of 2 or more nucleotides (e.g., 2-4 nucleotides in length).
Though not wishing to be bound by any theory, a mechanism which causes RNAi is considered to be as follows. When a molecule which causes RNAi, such as dsRNA, is introduced into a cell, an RNaseIII-like nuclease having a helicase domain (called dicer) cleaves the molecule at about 20 base pair intervals from the 3′ terminus in the presence of ATP in the case where the RNA is relatively long (e.g., 40 or more base pairs). As used herein, the term “siRNA” is an abbreviation of short interfering RNA and refers to short double-stranded RNA of 10 or more base pairs which are artificially chemically synthesized or biochemically synthesized, synthesized by an organism, or produced by double-stranded RNA of about 40 or more base pairs being degraded within the organism. siRNA typically has a structure comprising 5′-phosphate and 3′-OH, where the 3′ terminus projects by about 2 bases. A specific protein is bound to siRNA to form RISC (RNA-induced-silencing-complex). This complex recognizes and binds to mRNA having the same sequence as that of siRNA and cleaves mRNA at the middle of siRNA due to RNaseIII-like enzymatic activity. It is preferable that the relationship between the sequence of siRNA and the sequence of mRNA to be cleaved as a target is a 100% match. However, base mutations at a site away from the middle of siRNA do not completely remove the cleavage activity by RNAi, leaving partial activity, while base mutations in the middle of siRNA have a large influence and the mRNA cleavage activity by RNAi is considerably lowered. By utilizing such a characteristic, only mRNA having a mutation can be specifically degraded. Specifically, siRNA in which the mutation is provided in the middle thereof is synthesized and is introduced into a cell. Therefore, in the present invention, siRNA per se, as well as an agent capable of producing siRNA (e.g., representatively dsRNA of about 40 or more base pairs) can be used as an agent capable of eliciting RNAi.
Also, though not wishing to be bound by any theory, apart from the above-described pathway, the antisense strand of siRNA binds to mRNA and siRNA functions as a primer for RNA-dependent RNA polymerase (RdRP), so that dsRNA is synthesized. This dsRNA is a substrate for a dicer again, leading to production of new siRNA. It is intended that such a reaction is amplified. Therefore, in the present invention, siRNA per se, as well as an agent capable of producing siRNA are useful. In fact, in insects and the like, for example, 35 dsRNA molecules can substantially or completely degrade 1,000 or more copies of intracellular mRNA, and therefore, it will be understood that siRNA per se, as well as an agent capable of producing siRNA, is useful.
In the present invention, double-stranded RNA having a length of about 20 bases (e.g., representatively about 21 to 23 bases) or less than about 20 bases, called siRNA, can be used. Expression of siRNA in cells can suppress expression of a pathogenic gene targeted by the siRNA. Therefore, siRNA can be used for the treatment, prophylaxis, prognosis, and the like of diseases.
The siRNA of the present invention may be in any form as long as it can elicit RNAi.
In another embodiment, an agent capable of causing RNAi may have a short hairpin structure having a sticky portion at the 3′ terminus (shRNA; short hairpin RNA). As used herein, the term “shRNA” refers to a molecule of about 20 or more base pairs in which a single-stranded RNA partially contains a palindromic base sequence and forms a double-strand structure therein (i.e., a hairpin structure). shRNA can be artificially chemically synthesized. Alternatively, shRNA can be produced by linking sense and antisense strands of a DNA sequence in reverse directions and synthesizing RNA in vitro with T7 RNA polymerase using the DNA as a template. Though not wishing to be bound by any theory, it should be understood that after shRNA is introduced into a cell, the shRNA is degraded in the cell to a length of about 20 bases (e.g., representatively 21, 22, 23 bases), and causes RNAi as with siRNA, leading to the treatment effects of the present invention. It should be understood that such an effect is exhibited in a wide range of organisms, such as insects, plants, animals (including mammals), and the like. Thus, shRNA elicits RNAi as with siRNA and therefore can be used as an effective component of the present invention. shRNA may preferably have a 3′ protruding end. The length of the double-stranded portion is not particularly limited, but is preferably about 10 or more nucleotides, and more preferably about 20 or more nucleotides. Here, the 3′ protruding end may be preferably DNA, more preferably DNA of at least 2 nucleotides in length, and even more preferably DNA of 2-4 nucleotides in length.
An agent capable of causing RNAi used in the present invention may be artificially synthesized (chemically or biochemically) or naturally occurring. There is substantially no difference between the two in terms of the effect of the present invention. A chemically synthesized agent is preferably purified by liquid chromatography or the like.
An agent capable of causing RNAi used in the present invention can be produced in vitro. In this synthesis system, T7 RNA polymerase and T7 promoter are used to synthesize antisense and sense RNAs from template DNA. These RNAs are annealed and thereafter introduced into a cell. In this case, RNAi is caused via the above-described mechanism, thereby achieving the effect of the present invention. Here, for example, the introduction of RNA into a cell can be carried out using a calcium phosphate method.
Another example of an agent capable of causing RNAi according to the present invention is a single-stranded nucleic acid hybridizable to mRNA, or all nucleic acid analogs thereof. Such agents are useful for the method and composition of the present invention.
As used herein, the term “corresponding” amino acid or nucleic acid refers to an amino acid or nucleotide in a given polypeptide or polynucleotide molecule, which has, or is anticipated to have, a function similar to that of a predetermined amino acid or nucleotide in a polypeptide or polynucleotide as a reference for comparison. For example, in the case of ubiquitin, it refers to an amino acid contributing in a similar manner to the catalytic activity and present in a similar location as in the sequence (for example, glycine at the C-terminus) which is responsible for lysine. For example, in the case of nucleic acid sequence, the term refers to a similar portion which affects a similar function to the particular portion which it encodes.
As used herein, the term “corresponding” gene (e.g., a polypeptide or polynucleotide molecule) refers to a gene in a given species, which has, or is anticipated to have, a function similar to that of a predetermined gene in a species as a reference for comparison. When there are pluralities of genes having such a function, the term refers to a gene having the same evolutionary origin. Therefore, a gene corresponding to a given gene may be an ortholog of the given gene. Therefore, genes corresponding to those such as herpes virus type 6B and tumor antigen and the like, can be found in other organisms (for example, herpes virus type 7). Such a corresponding gene can be identified by techniques well known in the art. Therefore, for example, a corresponding gene in a given organism can be found by searching a sequence database of the organism (e.g., herpes virus 6B) using the sequence of a reference gene (e.g., mouse cyclin gene, etc.) as a query sequence. Alternatively, wet experiments are used for screening a library to find out the same.
As used herein, the term “isolated” means that naturally accompanying material is at least reduced, or preferably substantially or completely eliminated, in normal circumstances. Therefore, the term “isolated cell” refers to a cell substantially free from other accompanying substances (e.g., other cells, proteins, nucleic acids, etc.) in natural circumstances. The term “isolated” in relation to nucleic acids or polypeptides means that, for example, the nucleic acids or the polypeptides are substantially free from cellular substances or culture media when they are produced by recombinant DNA techniques; or precursory chemical substances or other chemical substances when they are chemically synthesized.
As used herein, the term “purified” biological agent (e.g., nucleic acids, proteins, and the like) refers to one from which at least a portion of naturally accompanying agents has been removed. Therefore, ordinarily, the purity of a purified biological agent is higher than that of the biological agent in a normal state (i.e., concentrated).
As used herein, the terms “purified” and “isolated” mean that the same type of biological agent is present preferably at least 75% by weight, more preferably at least 85% by weight, even more preferably at least 95% by weight, and most preferably at least 98% by weight.
As used herein, the term “homology” in relation to a sequence (e.g., a nucleic acid sequence, an amino acid sequence, etc.) refers to the proportion of identity between two or more gene sequences. Therefore, the greater the homology between two given genes, the greater the identity or similarity between their sequences. Whether or not two genes have homology is determined by comparing their sequences directly or by a hybridization method under stringent conditions. When two gene sequences are directly compared with each other, these genes have homology if the DNA sequences of the genes have representatively at least 50% identity, preferably at least 70% identity, more preferably at least 80%, 90%, 95%, 96%, 97%, 98%, or 99% identity with each other.
As used herein, “polynucleotides hybridizing under stringent conditions” refers to conditions commonly used and well known in the art. Such a polynucleotide can be obtained by conducting colony hybridization, plaque hybridization, Southern blot hybridization, or the like using a polynucleotide selected from the polynucleotides of the present invention. Specifically, a filter on which DNA derived from a colony or plaque is immobilized is used to conduct hybridization at 65° C. in the presence of 0.7 to 1.0 M NaCl. Thereafter, a 0.1 to 2-fold concentration SSC (saline-sodium citrate) solution (1-fold concentration SSC solution is composed of 150 mM sodium chloride and 15 mM sodium citrate) is used to wash the filter at 65° C. Polynucleotides identified by this method are referred to as “polynucleotides hybridizing under stringent conditions” Hybridization can be conducted in accordance with a method described in, for example, Molecular Cloning 2nd ed., Current Protocols in Molecular Biology, Supplement 1-38, DNA Cloning 1: Core Techniques, A Practical Approach, Second Edition, Oxford University Press (1995), and the like. Here, sequences hybridizing under stringent conditions exclude, preferably, sequences containing only A or T. “Hybridizable polynucleotide” refers to a polynucleotide which can hybridize to other polynucleotides under the above-described hybridization conditions. Specifically, the hybridizable polynucleotide includes at least a polynucleotide having a homology of at least 60% to the base sequence of DNA encoding a polypeptide having an amino acid sequence specifically herein disclosed, preferably a polynucleotide having a homology of at least 80%, and more preferably a polynucleotide having a homology of at least 95%.
The similarity, identity and homology of amino acid sequences and base sequences are herein compared using FASTA with the default parameters. Alternatively, an identity search may be conducted, for example, using NCBI's BLAST 2.2.9 (published May 12, 2004). As used herein, the value of identity usually refers to the value as a result of alignment with the BLAST as described above using the default parameters. If the change of parameters results in higher values, then the highest value is employed herein as the value of the identity. When a plurality of regions are evaluated for identity, the highest value is employed herein as the value of the identity.
As used herein, the term “search” indicates that a given nucleic acid sequence is utilized to find other nucleic acid base sequences having a specific function and/or property either electronically or biologically, or using other methods. Examples of an electronic search include, but are not limited to, BLAST (Altschul et al., J. Mol. Biol. 215:403-410 (1990)), FASTA (Pearson & Lipman, Proc. Natl. Acad. Sci., USA 85:2444-2448 (1988)), Smith and Waterman method (Smith and Waterman, J. Mol. Biol. 147:195-197 (1981)), and Needleman and Wunsch method (Needleman and Wunsch, J. Mol. Biol. 48:443-453 (1970)), and the like. Examples of a biological search include, but are not limited to, a macroarray in which genomic DNA is attached to a nylon membrane or the like or a microarray (microassay) in which genomic DNA is attached to a glass plate under stringent hybridization, PCR and in situ hybridization, and the like. As used herein, it is intended that promoters used in the present invention encompass a sequence corresponding to those identified by such an electronic or biological search.
As used herein, the term “expression” of a gene product, such as a gene, a polynucleotide, a polypeptide, or the like, indicates that the gene or the like is affected by a predetermined action in vivo to be changed into another form. Preferably, the term “expression” indicates that genes, polynucleotides, or the like are transcribed and translated into polypeptides. In one embodiment of the present invention, genes may be transcribed into mRNA. More preferably, these polypeptides may have post-translational processing modifications.
As used herein amino acids may be referred to with the generally known three-letter abbreviation or the one letter-abbreviation proposed by the IUPAC-IUB Biochemical Nomenclature Commission. Nucleotides may also be referred to with the generally known one-letter abbreviations which are generally accepted.
The letter codes are as follows:
Amino Acids:
3-letter
single-letter
reference
Ala
A
alanine
Cys
C
cysteine
Asp
D
aspartic acid
Glu
E
glutamic acid
Phe
F
phenylalanine
Gly
G
glycine
His
H
histidine
Ile
I
isoleucine
Lys
K
lysine
Leu
L
leucine
Met
M
methionine
Asn
N
asparagine
Pro
P
proline
Gln
Q
glutamine
Arg
R
arginine
Ser
S
serine
Thr
T
threonine
Val
V
valine
Trp
W
tryptophane
Tyr
Y
tyrosine
Asx
asparatic acid or asparagine
Glx
glutamine or glutamic acid
Xaa
unknown or other amino acid
Base (Nucleotide)
abbreviation
reference
a
adenine
g
guanine
c
cytosine
t
thymine
u
uracyl
r
guanine or adenine purine
y
thymine/uracil or cytosine purimidine
m
adenin or cytocine amino group
k
guanine or thymine uracil keto group
s
guanin or cytosine
w
adenine or thymine/uracil
b
guanine or cytocine or thymine/uracil
d
adenine or guanine or thymine/uracil
h
adenine or cytosine or thymine/uracil
v
adenine or guanine or cytosine
n
adenine or guanine or cytosine or
thymine/uracil, unknown or other base
As used herein, the term “fragment” with respect to a polypeptide or polynucleotide refers to a polypeptide or polynucleotide having a sequence length ranging from 1 to n−1 with respect to the full length of the reference polypeptide or polynucleotide (of length n). The length of the fragment can be appropriately changed depending on the purpose. For example, in the case of polypeptides, the lower limit of the length of the fragment includes 3, 4, 5, 6, 7, 8, 9, 10, 15, 20, 25, 30, 40, 50 or more nucleotides. Lengths represented by integers which are not herein specified (e.g., 11 and the like) may be appropriate as a lower limit. For example, in the case of polynucleotides, the lower limit of the length of the fragment includes 5, 6, 7, 8, 9, 10, 15, 20, 25, 30, 40, 50, 75, 100, 200, 300, 400, 500, 600, 700, 800, 900, 1000 or more nucleotides. Lengths represented by integers which are not herein specified (e.g., 11 and the like) may be appropriate as a lower limit.
A polypeptide used in the present invention may have at least one (for example, one or several or more) amino acid substitutions, addition and/or deletion in the amino acid sequence, as long as it has substantially identical function as the wild type polypeptide.
It is well known that if a given amino acid is substituted with another amino acid having a similar hydrophobicity index, the resultant protein may still have a biological function similar to that of the original protein (e.g., a protein having an equivalent enzymatic activity). For such an amino acid substitution, the hydrophobicity index is preferably within ±2, more preferably within ±1, and even more preferably within ±0.5. It is understood in the art that hydrophobicity is considered in the modification of a protein. As described in U.S. Pat. No. 4,554,101, amino acid residues are given the following hydrophilicity indices: arginine (+3.0); lysine (+3.0); aspartic acid (+3.0±1); glutamic acid (+3.0±1); serine (+0.3); asparagine (+0.2); glutamine (+0.2); glycine (0); threonine (−0.4); proline (−0.5±1) alanine (−0.5); histidine (−0.5); cysteine (−1.0); methionine (−1.3); valine (−1.5); leucine (−1.8); isoleucine (−1.8); tyrosine (−2.3); phenylalanine (−2.5); and tryptophan (−3.4). It is understood that an amino acid may be substituted with another amino acid which has a similar hydrophilicity index and can still provide a biological equivalent. For such an amino acid substitution, the hydrophilicity index is preferably within ±2, more preferably ±1, and even more preferably ±0.5. A hydrophilicity index is also useful for modification of an amino acid sequence of the present invention. As described in U.S. Pat. No. 4,554,101, amino acid residues are given the following hydrophilicity indices: arginine (+3.0); lysine (+3.0); aspartic acid (+3.0±1); glutamic acid (+3.0±1); serine (+0.3); asparagine (+0.2); glutamine (+0.2); glycine (0); threonine (−0.4); proline (−0.5±1) alanine (−0.5); histidine (−0.5); cysteine (−1.0); methionine (−1.3); valine (−1.5); leucine (−1.8); isoleucine (−1.8); tyrosine (−2.3); phenylalanine (−2.5); and tryptophan (−3.4). It is understood that an amino acid may be substituted with another amino acid which has a similar hydrophilicity index and can still provide a biological equivalent. For such an amino acid substitution, the hydrophilicity index is preferably within ±2, more preferably ±1, and even more preferably ±0.5.
The term “conservative substitution” as used herein refers to an amino acid substitution in which a substituted amino acid and a substituting amino acid have similar hydrophilicity indices or/and hydrophobicity indices. For example, the conservative substitution is carried out between amino acids having a hydrophilicity or hydrophobicity index of within ±2, preferably within ±1, and more preferably within ±0.5. Examples of conservative substitution include, but are not limited to, substitutions within each of the following residue pairs: arginine and lysine; glutamic acid and aspartic acid; serine and threonine; glutamine and asparagine; and valine, leucine, and isoleucine, which are well known to those skilled in the art.
As used herein, the term “variant” refers to a substance, such as a polypeptide, polynucleotide, or the like, which differs partially from the original substance. Examples of such a variant include a substitution variant, an addition variant, a deletion variant, a truncated variant, an allelic variant, and the like. Examples of such a variant include, but are not limited to, a nucleotide or polypeptide having one or several substitutions, additions and/or deletions or a nucleotide or polypeptide having at least one substitution, addition and/or deletion. The term “allele” as used herein refers to a genetic variant located at a locus identical to a corresponding gene, where the two genes are distinguishable from each other. Therefore, the term “allelic variant” as used herein refers to a variant which has an allelic relationship with a given gene. Such an allelic variant ordinarily has a sequence the same as or highly similar to that of the corresponding allele, and ordinarily has almost the same biological activity, though it rarely has different biological activity. The term “species homolog” or “homolog” as used herein refers to one that has an amino acid or nucleotide homology with a given gene in a given species (preferably at least 60% homology, more preferably at least 80%, at least 85%, at least 90%, and at least 95% homology). A method for obtaining such a species homolog is clearly understood from the description of the present specification. The term “orthologs” (also called orthologous genes) refers to genes in different species derived from a common ancestry (due to speciation). For example, in the case of the hemoglobin gene family having multigene structure, human and mouse α-hemoglobin genes are orthologs, while the human α-hemoglobin gene and the human β-hemoglobin gene are paralogs (genes arising from gene duplication). Orthologs are useful for estimation of molecular phylogenetic trees. Usually, orthologs in different species may have a function similar to that of the original species. Therefore, orthologs of the present invention may be useful in the present invention.
As used herein the term “functional variant” refers to a variant which retains a biological activity (in particular, promoter activity” which the sequence of standard is responsible for.
As used herein, the term “conservative (or conservatively modified) variant” applies to both amino acid and nucleic acid sequences. With respect to particular nucleic acid sequences, conservatively modified variants refer to those nucleic acids which encode identical or essentially identical amino acid sequences. Because of the degeneracy of the genetic code, a large number of functionally identical nucleic acids encode any given protein. For example, the codons GCA, GCC, GCG and GCU all encode the amino acid alanine. Thus, at every position where an alanine is specified by a codon, the codon can be altered to any of the corresponding codons described without altering the encoded polypeptide. Such nucleic acid variations are “silent variations” which represent one species of conservatively modified variation. In a nucleic acid, a conservative substitution can be confirmed by measuring promoter activity, for example.
In order to prepare functionally equivalent polypeptides, amino acid additions, deletions, or modifications can be performed in addition to amino acid substitutions. Amino acid substitution(s) refers to the replacement of at least one amino acid of an original peptide with different amino acids, such as the replacement of 1 to 10 amino acids, preferably 1 to 5 amino acids, and more preferably 1 to 3 amino acids with different amino acids. Amino acid addition(s) refers to the addition of at least one amino acid to an original peptide chain, such as the addition of 1 to 10 amino acids, preferably 1 to 5 amino acids, and more preferably 1 to 3 amino acids to an original peptide chain. Amino acid deletion(s) refers to the deletion of at least one amino acid, such as the deletion of 1 to 10 amino acids, preferably 1 to 5 amino acids, and more preferably 1 to 3 amino acids. Amino acid modification includes, but is not limited to, amidation, carboxylation, sulfation, halogenation, truncation, lipidation, alkylation, glycosylation, phosphorylation, hydroxylation, acylation (e.g., acetylation), and the like. Amino acids to be substituted or added may be naturally-occurring or nonnaturally-occurring amino acids, or amino acid analogs. Naturally-occurring amino acids are preferable.
Nucleic acid embodiment of the polypeptide to be expressed as used herein refers to a nucleic acid which allows expression of the protein embodiment of the polypeptide. Such a nucleic acid includes one in which a part of the sequence of the nucleic acid is deleted or is substituted with other base(s), or an additional nucleic acid sequence is inserted, as long as a polypeptide expressed by the nucleic acid has substantially the same activity as that of the naturally-occurring polypeptide, as described above. Alternatively, an additional nucleic acid may be linked to the 5′ terminus and/or 3′ terminus of the nucleic acid. The nucleic acid molecule may include one that is hybridizable to a gene encoding a polypeptide under stringent conditions and encodes a polypeptide having substantially the same function as that of that polypeptide. Such a gene is known in the art and can be used in the present invention.
The above-described nucleic acid can be obtained by a well-known PCR method, i.e., chemical synthesis. This method may be combined with, for example, site-specific mutagenesis, hybridization, or the like.
As used herein, the term “substitution, addition or deletion” for a polypeptide or a polynucleotide refers to the substitution, addition or deletion of an amino acid or its substitute, or a nucleotide or its substitute with respect to the original polypeptide or polynucleotide. This is achieved by techniques well known in the art, including a site-specific mutagenesis technique and the like. A polypeptide or a polynucleotide may have any number (>0) of substitutions, additions, or deletions. The number can be as large as a variant having such a number of substitutions, additions or deletions can maintain an intended function (e.g., the information transfer function of hormones and cytokines, etc.). For example, such a number may be one or several, and preferably within 20% or 10% of the full length sequence, or no more than 100, no more than 50, no more than 25, or the like.
(Promoter)
As used herein, the term “promoter (or promoter sequence)” refers to a base sequence which determines the initiation site of transcription of a gene and is a DNA region which directly regulates the frequency of transcription. Transcription is started by RNA polymerase binding to a promoter. Accordingly, as used herein a portion having the function of a promoter of a gene refers to “a promoter portion”. A promoter region can be deduced by predicting the protein coding region in a genomic base sequence using DNA analysis software. Deduced promoter regions are usually located upstream of the structural gene although it varies, and is not limited thereto, and may also be downstream of the structural gene.
As used herein, the term “MIE promoter” refers to a major immediate early promoter, which is a promoter of a gene which is immediately transcribed by a transcription factor derived from a host and a virion after viral infection. The MIE gene may be identified by RT-PCR using an RNA extracted from an infected cell treated with cycloheximide.
As used herein, the term “U95 promoter” refers to a promoter of the immediate early gene U95. U95 is also an immediate early gene, and thus is immediately transcribed by a transcription factor derived from a host or a virion after the viral infection.
As used herein, the identification method of a promoter is as follows: some sequences in the vicinity of the structural gene are screened (for example, using an expression cassette described in the Examples), and the sequence having the gene expression promoting activity is mapped. As such, a sequence having significant promoting activity may be identified. Usually, it is located upstream of the structural gene, but is not limited thereto.
As used herein, the term “HHV6B MIE promoter” or “MIE promoter of HHV6B” refers to any sequence having promoter activity in SEQ ID NO: 1. Preferably, the promoter has position −814 to position 0 from the transcription initiation point in SEQ ID NO: 1. Such a sequence includes, but is not limited to SEQ ID NO: 1 or a sequence corresponding thereto. In the expression control of HHV6B gene, it is preferable to be located in the region at −574 to −427 from the upstream, and preferably, in the region of −1051 to −427, and the base sequence thereof includes sequences set forth in SEQ ID NO: 15, 16 and the like. Amongst them, it has been elucidated herein that NF-κB and AP-1 motifs (−603 to −594 from the transcription initiation point as the origin, corresponds to NF-κB motif, and −488 to −478 and −249 to −239 correspond to the AP-1 motifs) may be motifs from experiments of base sequence substitution. Accordingly, preferably, the HHV6B MIE promoter of the present invention comprises: (a) a polynucleotide having the base sequence set forth in SEQ ID NO: 1, or the base sequence corresponding thereto or a fragment sequence thereof; (b) a polynucleotide of an allelic variant of the base sequence set forth in SEQ ID NO: 1 or the base sequence corresponding thereto or a fragment sequence thereof; (c) a polynucleotide which hybridizes a polynucleotide of any of (a) or (b) and has a biological activity thereof; or (d) a polynucleotide which consists of the base sequence of any of (a) to (c) or a complement sequence thereof with at least 70% identity, and has a biological activity thereof.
As used herein, the term “HHV7 MIE promoter” or “MIE promoter of HHV7” refers to any sequence having promoter activity in SEQ ID NO: 2. Preferably, the promoter has position −493 to position +22 from the transcription initiation point in SEQ ID NO: 2. Such a sequence includes, but is not limited to SEQ ID NO: 2 or a sequence corresponding thereto. In the expression control of the HHV7 gene, it is preferable to be located in the region at −427 from the upstream, and preferably, in the region of −493, and the base sequence thereof includes sequences set forth in SEQ ID NO: 2 and the like. Amongst them, it has been elucidated herein that NF-κB motifs (−464 to −478 and −359 to −350 from the transcription initiation point as the origin, corresponds to NF-κB motifs) may be motifs from experiments of base sequence substitution. Accordingly, preferably, the HHV7 MIE promoter of the present invention comprises: (a) a polynucleotide having the base sequence set forth in SEQ ID NO. 2, or the base sequence corresponding thereto or a fragment sequence thereof; (b) a polynucleotide of an allelic variant of the base sequence set forth in SEQ ID NO. 2 or the base sequence corresponding thereto or a fragment sequence thereof; (c) a polynucleotide which hybridizes a polynucleotide of any of (a) or (b) and has a biological activity thereof; or (d) a polynucleotide which consists of the base sequence of any of (a) to (c) or a complement sequence thereof with at least 70% identity, and has a biological activity thereof.
As used herein, the term “HHV7 U95 promoter” or “U95 promoter of HHV7” refers to any sequence having promoter activity in SEQ ID NO: 12. Preferably, the promoter has position −484 to position +16 from the transcription initiation point in SEQ ID NO: 12. In the expression control of the HHV7 gene, it is preferable to be located in the region at −379 from the upstream, and preferably, in the region of −484, and the base sequence thereof includes sequences set forth in SEQ ID NO: 2 and the like. Amongst them, it has been elucidated herein that NF-κB motifs (−478 to −469 and −373 to −364 from the transcription initiation point as the origin, correspond to NF-κB motifs) may be motifs from experiments of base sequence substitution. Accordingly, preferably, the HHV7 U95 promoter of the present invention comprises: (a) a polynucleotide having the base sequence set forth in SEQ ID NO. 12, or the base sequence corresponding thereto or a fragment sequence thereof; (b) a polynucleotide of an allelic variant of the base sequence set forth in SEQ ID NO. 12 or the base sequence corresponding thereto or a fragment sequence thereof; (c) a polynucleotide which hybridizes a polynucleotide of any of (a) or (b) and has a biological activity thereof; or (d) a polynucleotide which consists of the base sequence of any of (a) to (c) or a complement sequence thereof with at least 70% identity, and has a biological activity thereof.
“Constitutive” expression of a gene by a promoter of the present invention as used herein refers to a trait in which expression is found at a substantial but unchanged amount in any tissue of an organism during any stage in the course of the growth of the organism. Specifically, when northern blot analysis is carried out under conditions similar to those in the examples described herein, if substantial and similar expression is observed in the same or corresponding site thereof on any time points (e.g. two or more time points such as day 5 and day 15), the expression is regarded as being constitutive by the definition in the present invention. Constitutive promoters are believed to play a role in the homeostasis of organisms in a normal growth environment. These traits can be determined by extracting RNA from an arbitrary portion and subjecting the RNA to northern blot analysis to analyze expression amounts.
“Enhancer” may be used so as to enhance the expression efficiency of a gene of interest. As such an enhancer, an enhancer region containing an upstream sequence within the CaMV35S promoter is preferable. A plurality of enhancers or a single enhancer may be used, or no enhancer may be used. A region in a promoter which enhances the activity of the promoter may also be referred to as an enhancer.
As used herein, “operatively linked” or “operative link” refers to the fact that the expression (operation) of a desired sequence is located under the control of a transcription regulation sequence (e.g. promoter, enhancer or the like) or a translation regulation sequence. In order that a promoter is operably linked to a gene, the promoter is usually located immediately upstream of the gene, but is not necessarily located in a flanking manner.
(Nucleic Acid Construct)
As used herein, the term “nucleic acid construct” or “gene cassette” are interchangeably used to refer to a nucleic acid sequence comprising nucleic acid (for example, DNA, RNA) encoding a gene, a nucleic acid sequence comprising a gene promoter operably linked thereto (such that it can control the expression of the nucleic acid), a promoter, and optionally a heterologous gene operably linked thereto (i.e., in frame). It is intended that the use of this cassette or the construct optionally in combination with another regulatory element is encompassed in the present invention. Preferably expression cassettes or nucleic acid constructs are those which are amenable to specific restriction enzyme digestion and are feasible for recovery.
When a gene is mentioned herein, the term “recombinant vector” refers to a vector transferring a polynucleotide sequence of interest to a target cell. Such a vector is capable of self-replication or incorporation into a chromosome of a host cell (e.g., a prokaryotic cell, yeast, an animal cell, a plant cell, an insect cell, an individual animal, and an individual plant, etc.), and contains a promoter at a site suitable for transcription of a polynucleotide of the present invention. In the present application, for example, BAC vectors may be used. BAC vector refers to a plasmid produced based on the F plasmid of an E. coli , and is capable of propagating and stably maintaining a DNA fragment of about 300 kb or greater in size, in a bacteria such as E. coli or the like. BAC vector comprises at least a region essential for replication of BAC vectors. Such a region essential for replication includes, for example, oriS, a replication initiation point of F plasmid, or a variant thereof.
As used herein, “selective marker” refers to a gene which functions as guidance for selecting a host cell comprising a nucleic acid construct or a vector. Selective markers include, but are not limited to: fluorescent markers, luminescent markers and drug selective markers. “Fluorescent markers” include, but are not limited to gene encoding fluorescence proteins such as green fluorescent protein (GFP), cyan fluorescent protein (CFP), yellow fluorescent protein (YFP), red fluorescent protein (dsRFP). “Luminescent markers” include but are not limited to genes encoding luminescent proteins such as luciferases. “Drug selective markers” include but are not limited to: hypoxanthine guanine phosphoribosyl transferase (hprt), dihydrofolate reductase gene, glutamine synthase gene, aspartate transaminase, metallothionein (MT), adenosine aminase (ADA), AMP deaminase (AMPD1,2), xanthine-guanine-phosphoribosyl transferase, UMP synthase, P-glycoprotein, asparagine synthase, and ornithine decarboxylase. A combination of a drug in conjunction with these drug selective markers including those encoding proteins, for example: the combination of dihydrofolate reductase (DHFR) gene and methotrexate (MTX); the combination of glutamine synthase (GS) gene and methionine sulfoximine (Msx); the combination of aspartate transaminase (AST) gene and N-phosphone acetyl-L-aspartate (PALA); the combination of MT gene and cadmium (Cd 2+ ); the combination of adenosine deaminase (ADA) gene and adenosine, alanosine, 2′-deoxycoformycin; the combination of AMP deaminase (AMPD1.2) gene and adenine, azaserine and coformycin; the combination of xanthine-guanine-phosphoribosyl transferase gene and mycophenolic acid; the combination of UMP synthase gene and 6-azauridine, pyrazofuran; the combination of P-glycoprotein (P-gp, MDR) gene and multi drugs; the combination of aspartate synthase (AS) gene and β-aspartyl hydroxamic acid or albizziin; ornithine carboxylase (ODC) gene and α-difluoromethyl-ornithine (DFMO) and the like.
As used herein, the term “expression vector” refers to a nucleic acid sequence comprising a structural gene and a promoter for regulating expression thereof, and in addition, various regulatory elements in a state that allows them to operate within host cells. The regulatory element may include, preferably, terminators, selectable markers such as drug-resistance genes (e.g. kanamycin resistant gene, hygromycin resistant gene and the like), and enhancers. It is well known in the art that a type of expression vector of a living organism such as an animal and a species of a regulatory element used may vary depending on the type of host cell used.
As used herein, the term “recombinant vector” refers to a vector transferring a polynucleotide sequence of interest to a target cell. Such a vector is capable of self-replication or incorporation into a chromosome in a host cell (e.g., a prokaryotic cell, yeast, an animal cell, a plant cell, an insect cell, an individual animal, and an individual plant, etc.), and contains a promoter at a site suitable for transcription of a polynucleotide of the present invention.
As used herein, the term “terminator” refers to a sequence which is located downstream of a protein-encoding region of a gene and which is involved in the termination of transcription when DNA is transcribed into mRNA, and the addition of a poly-A sequence. It is known that a terminator contributes to the stability of mRNA, and has an influence on the amount of gene expression. Terminators include, but are not limited to, a sequence including AATAAA.
As used herein, the term “foreign gene” to a particular organism refers to a gene which does not natively exist in the particular organism. Such a foreign gene may be a gene modified from a gene which naturally occurs in the particular organism, or a gene which naturally occurs in an organism that is different from the particular organism (such as ADA gene), or an artificially synthesized gene, or a complex thereof such as a fusion. An organism comprising such a foreign gene may express a genetic product which is not expressed in nature. For example, a recessive gene to be deleted (for example, ADA gene, PNP gene, γ c chain gene, TAP gene, MHC II gene, X-linked WASP, CD40 ligand, PI3K-like gene, DNA helicase) may be used as a foreign gene.
As used herein, the foreign gene may be a gene of a cytokine. As used herein, the term “cytokine” is defined as in the broadest sense used in the art, and a physiologically active substance which is produced from a cell and acts on the same cell or a different cell. Cytokines are generally a protein or a polypeptide, and have a controlling action of immunological response, regulation of endocrine system, regulation of the nerve system, antitumor activity, antiviral activity, regulation of cell proliferation, regulation of cellular differentiation and the like. As used herein, cytokines may exist in a form of protein or nucleic acid, and at the actual time of action, cytokines usually mean a protein form. As used herein, the term “growth factor” refers to a substance which promotes or controls the growth of a cell. Growth factors may substitute the action of serum macromolecular substances by addition to a medium in cell culture or tissue culture. Many growth factors have been found to function as a regulation factor of a differentiation state other than growth of a cell. Cytokines typically include interleukins, chemokines, hematopoietic factors such as colony stimulation factors, tumor necrosis factors, interferons. Growth factors typically include platelet derived growth factor (PDGF), epidermal growth factor (EGF), fibroblast growth factor (FGF), hepatocytic growth factor (HGF), vessel endothelial growth factor (VEGF), and the like, which show growth activity.
In the present invention, those having homology with a foreign gene of a native form as described above may be used as a foreign gene to be expressed. Such foreign genes having such homology include, but are not limited to: for example, when conducting comparison using default parameters of Blast in comparison to a foreign gene of reference to be compared, nucleic acids having sequences of identity or similarity of at least about 30%, at least about 35%, at least about 40%, at least about 30%, at least about 45%, at least about 50%, at least about 55%, at least about 60%, at least about 65%, at least about 70%, at least about 75%, at least about 80%, at least about 85%, at least about 90%, at least about 95%, at least about 99%, or polypeptides having amino acid sequence of identity or similarity of at least about 30%, at least about 35%, at least about 40%, at least about 30%, at least about 45%, at least about 50%, at least about 55%, at least about 60%, at least about 65%, at least about 70%, at least about 75%, at least about 80%, at least about 85%, at least about 90%, at least about 95%, at least about 99%.
As used herein, the term “expression” of a gene product, such as a gene, a polynucleotide, a polypeptide, or the like, indicates that the gene or the like is affected by a predetermined action in vivo to be changed into another form. Preferably, the term “expression” indicates that genes, polynucleotides, or the like are transcribed and translated into polypeptides. In one embodiment of the present invention, genes may be transcribed into mRNA. More preferably, these polypeptides may have post-translational processing modifications.
Accordingly, as used herein, “reduction” of “expression” of a gene, a polynucleotide, a polypeptide or the like refers to when an agent of the present invention is subjected to an action, whereby the amount of expression is significantly reduced compared to that when the agent is not subjected to an action. Preferably, the reduction of expression includes a reduction of the level of polypeptide expression. As used herein, the “increase” of “expression” of a gene, a polynucleotide, a polypeptide or the like refers to when an agent of the present invention is subjected to an action (or an agent relating to gene expression into a cell, for example, a gene to be expressed or an agent for regulating the same), whereby the amount of expression is significantly increased compared to when the agent is not subjected to an action. Preferably, the increase of expression includes an increase in the level of polypeptide expression. As used herein, the term “induction” of “expression” of a gene refers to an increase in the level of expression of the gene by acting an agent on a cell. Accordingly, the induction of expression encompasses when the level of expression of the gene is observed to increase from an observed level of no expression, to a noticeable level of expression of the gene.
As used herein, the term “specifically express(ing)” of a gene refers to expression in a different level (preferably in a higher level) in a specific site or period of time than that of the other site or period of time. Specific expression may refer to expression in a certain site (specific site) or may also refer to the expression including that in another site. Preferably, specific expression refers to the expression in the certain site only.
Methods of introducing a recombinant vector are also achieved by any of the above-mentioned methods for introducing DNA into a cell, and include for example, transfection, transduction, transformation and the like, such as calcium phosphate, liposome methods, DEAE dextran methods, electroporation methods, particle gun methods (gene gun), and the like, lipofection, spheroplast Proc. Natl. Acad. Sci. USA, 84, 1929 (1978)], lithium acetate method [J. Bacteriol., 153, 163 (1983)], a method described in Proc. Natl. Acad. Sci. USA, 75, 1929 (1978) and the like.
Transitional expression of Cre enzyme, DNA mapping on the chromosomes and the like, used in a method for removing a genome or genomic locus used herein or the like are well known in the art as described in “FISH jikken purotokooru hito/genomu kaiseki kara senshokutai/idenshi shindan made (FISH Experimental Protocol: from human/genomic analysis to chromosomal/genetic diagnosis)” one of “Saibo Kogaku Bessatsu Jikken Purotokooru siriizu (Cell Engineering, Special Edition, Experimental Protocol Series), ed. Ken'ichi Matsubara, Hiroshi Yoshikawa, Shujunsha (Tokyo) and the like.
As used herein, gene expression (e.g., mRNA expression, polypeptide expression) may be “detected” or “quantified” by an appropriate method, including mRNA measurement and immunological measurement. Examples of molecular biological measurement methods include Northern blotting methods, dot blotting methods, PCR methods, and the like. Examples of immunological measurement methods include ELISA methods, RIA methods, fluorescent antibody methods, Western blotting methods, immunohistological staining methods, and the like, where a microtiter plate may be used. Examples of quantification methods include ELISA methods, RIA methods, and the like. A gene analysis method using an array (e.g., a DNA array, a protein array, etc.) may be used. The DNA array is widely reviewed in Saibo-Kogaku [Cell Engineering], special issue, “DNA Microarray and Up-to-date PCR Method”, edited by Shujun-sha. The protein array is described in detail in Nat. Genet. 2002 December; 32 Suppl:526-32. Examples of methods for analyzing gene expression include, but are not limited to, RT-PCR methods, RACE methods, SSCP methods, immunoprecipitation methods, two-hybrid systems, in vitro translation methods, and the like in addition to the above-described techniques. Other analysis methods are described in, for example, “Genome Analysis Experimental Method, Yusuke Nakamura's Lab-Manual, edited by Yusuke Nakamura, Yodo-sha (2002), and the like. All of the above-described publications are herein incorporated by reference.
As used herein, the term “expression level (or amount)” refers to the amount of a polypeptide or mRNA expressed in a subject cell. The term “expression level” includes the level of protein expression of a polypeptide evaluated by any appropriate method using an antibody, including immunological measurement methods (e.g., an ELISA method, an RIA method, a fluorescent antibody method, a Western blotting method, an immunohistological staining method, and the like, or the mRNA level of expression of a polypeptide evaluated by any appropriate method, including molecular biological measurement methods (e.g., a Northern blotting method, a dot blotting method, a PCR method, and the like). The term “change in expression level” indicates that an increase or decrease in the protein or mRNA level of expression of a polypeptide evaluated by an appropriate method including the above-described immunological measurement method or molecular biological measurement method.
As used herein, the terms “transformation”, “transduction” and “transfection” are used interchangeably unless otherwise mentioned, and refer to introduction of a nucleic acid into host cells. As a transformation method, any technique for introducing DNA into host cells can be used, including various well-known techniques, such as, for example, the electroporation method, the particle gun method (gene gun), the calcium phosphate method, and the like.
As used herein, the term “transformant” refers to the whole or a part of an organism, such as a cell, which is produced by transformation. Examples of a transformant include prokaryotic cells, yeast, animal cells, plant cells, insect cells and the like. Transformants may be referred to as transformed cells, transformed tissue, transformed hosts, or the like, depending on the subject.
As used herein, all of the forms are encompassed, however, a particular form may be specified in a particular context.
Examples of prokaryotic cells include prokaryotic cells of the genera Escherichia, Serratia, Bacillus, Brevibacterium, Corynebacterium, Microbacterium, Pseudomonas , and the like, e.g., Escherichia coli XL1-Blue, Escherichia coli XL2-Blue, Escherichia coli DH1, Escherichia coli MC1000, Escherichia coli KY3276, Escherichia coli W1485, Escherichia coli JM109, Escherichia coli HB101, Escherichia coli No. 49, Escherichia coli W3110, Escherichia coli NY49, Escherichia coli BL21 (DE3), Escherichia coli BL21 (DE3) S, Escherichia coli HMS174 (DE3), Escherichia coli HMS174 (DE3) pLysS, Serratia ficaria, Serratia fonticola, Serratia liquefaciens, Serratia marcescens, Bacillus subtilis, Bacillus amyloliquefaciens, Brevibacterium ammmoniagenes, Brevibacterium immariophilum ATCC14068, Brevibacterium saccharolyticum ATCC14066, Corynebacterium glutamicum ATCC13032, Corynebacterium glutamicum ATCC14067, Corynebacterium glutamicum ATCC13869, Corynebacterium acetoacidophilum ATCC13870, Microbacterium ammoniaphilum ATCC15354, Pseudomonas sp. D-0110, and the like.
Examples of animal cells include cord blood mononuclear cells, peripheral blood mononuclear cells, Sup-T1 cells, and the like.
The term “animal” is used herein in its broadest sense and refers to vertebrates and invertebrates (e.g., arthropods). Examples of animals include, but are not limited to, any of the class Mammalia, the class Aves, the class Reptilia, the class Amphibia, the class Pisces, the class Insecta, the class Vermes, and the like.
As used herein, the term “tissue” in relation to organisms refers to an aggregate of cells having substantially the same function. Therefore, a tissue may be a part of an organ. Organs usually have cells having the same function, and may have coexisting cells having slightly different functions. Therefore, as used herein, tissues may have various kinds of cells as long as a certain property is shared by the cells.
As used herein, the term “organ” refers to a structure which has a single independent form and in which one or more tissues are associated together to perform a specific function. In plants, examples of organs include, but are not limited to, callus, root, stem, trunk, leaf, flower, seed, embryo bud, embryo, fruit, and the like. In animals, examples of organs include, but are not limited to, stomach, liver, intestine, pancreas, lung, airway, nose, heart, artery, vein, lymph node (lymphatic system), thymus, ovary, eye, ear, tongue, skin, and the like.
As used herein, the term “transgenic” refers to incorporation of a specific gene into an organism (e.g., plants or animals (mice, etc.)) or such an organism having an incorporated gene.
When organisms of the present invention are animals, the transgenic organisms can be produced by a microinjection method (a trace amount injection method), a viral vector method, an embryonic stem (ES) cell method, a sperm vector method, a chromosome fragment introducing method (transsomic method), an episome method, or the like. These transgenic animal producing techniques are well known in the art.
As used herein, the term “screening” refers to selection of a substance, a host cell, a virus, or the like having a given specific property of interest from a number of candidates using a specific operation/evaluation method. It will be understood that the present invention encompasses viruses having desired activity obtained by screening.
As used herein, the terms “chip” or “microchip” are used interchangeably to refer to a micro-integrated circuit which has versatile functions and constitutes a portion of a system. Examples of a chip include, but are not limited to, DNA chips, protein chips, and the like.
The herpesvirus promoters of the present invention can be used as an ingredient of a pharmaceutical composition for the treatment, prevention, and/or therapy of lymphatic lineage or hemato-lineage, immune, and infectious diseases.
As used herein, the term “effective amount” in relation to a drug refers to an amount which causes the drug to exhibit intended efficacy. As used herein, an effective amount corresponding to a smallest concentration may be referred to as a minimum effective amount. Such a minimum effective amount is well known in the art. Typically, the minimum effective amount of a drug has been determined or can be determined as appropriate by those skilled in the art. The determination of such an effective amount can be achieved by actual administration, use of an animal model, or the like. The present invention is also useful for the determination of such an effective amount.
As used herein, the term “pharmaceutically acceptable carrier” refers to a material which is used for production of a pharmaceutical agent or an agricultural chemical (e.g., an animal drug), and has no adverse effect on effective ingredients. Examples of such a pharmaceutically acceptable carrier include, but are not limited to: antioxidants, preservatives, colorants, flavoring agents, diluents, emulsifiers, suspending agents, solvents, fillers, bulking agents, buffers, delivery vehicles, excipients, and/or agricultural or pharmaceutical adjuvants.
The type and amount of a pharmaceutical agent used in the treatment method of the present invention can be easily determined by those skilled in the art based on information obtained by the method of the present invention (e.g., information relating to a disease) in view of the purpose of use, the target disease (type, severity, etc.), the subject's age, size, sex, and case history, the morphology and type of a site of a subject of administration, or the like. The frequency of subjecting a subject (patient) to the monitoring method of the present invention is also easily determined by those skilled in the art with respect to the purpose of use, the target disease (type, severity, etc.), the subject's age, size, sex, and case history, the progression of the therapy, and the like. Examples of the frequency of monitoring the state of a disease include once per day to once per several months (e.g., once per week to once per month). Preferably, monitoring is performed once per week to once per month with reference to the progression.
As used herein, the term “instructions” refers to a description of the method of the present invention for a person who performs administration, such as a medical doctor, a patient, or the like. Instructions state when to administer a medicament of the present invention, such as immediately after or before radiation therapy (e.g., within 24 hours, etc.). The instructions are prepared in accordance with a format defined by an authority of a country in which the present invention is practiced (e.g., Health, Labor and Welfare Ministry in Japan, Food and Drug Administration (FDA) in the U.S., and the like), explicitly describing that the instructions are approved by the authority. The instructions are so-called package insert and are typically provided in paper media. The instructions are not so limited and may be provided in the form of electronic media (e.g., web sites, electronic mails, and the like provided on the Internet).
In a therapy of the present invention, two or more pharmaceutical agents may be used as required. When two or more pharmaceutical agents are used, these agents may have similar properties or may be derived from similar origins, or alternatively, may have different properties or may be derived from different origins. A method of the present invention can be used to obtain information about the drug resistance level of a method of administering two or more pharmaceutical agents.
Culturing methods used in the present invention are described and supported in, for example, “Doubutsu Baiyosibo Manuaru (Animal Culture Cell Manual), Eeno et al. eds., Kyoritsu shuppan, 1993, the entirety of which is hereby incorporated by reference.
(Methods for Producing Polypeptides)
The polypeptides of the present invention may be produced by culturing a transformant derived from a microorganism or an animal cell possessing a recombinant vector with a DNA encoding the polypeptide of the present invention incorporated therein, in a normal culturing manner, and producing and depositing the polypeptide of the present invention, and recovering the polypeptide of the present invention from the culture of the present invention.
The method for culturing the transformant of the present invention in a medium may be conducted according to the normal methods used in the culture of a host. Culture medium for culturing the transformant obtained by using a prokaryotic cell such as E. coli and the like or a eukaryotic cell such as yeast as a host, include those comprising a carbon source, nitrogen source, inorganic salts and the like which can be assimilated by the organism of the present invention, and in which a transformant can efficiently be cultured, which may be natural or synthetic.
As a carbon source, those which can be assimilated by the microorganism can be used and include, for example, glucose, fructose, sucrose, sugar or honey containing the same, starch, starch hydrolysate, organic acids such as acetic acid and propionic acid, alcohols such as ethanol and propanol and the like.
As a nitrogen source, for example, the following can be used: ammonia, a variety of ammonium salts of inorganic or organic acid salt such as ammonium chloride, ammonium sulfate, ammonium acetate, ammonium phosphate, other nitrogen containing substance and the like, peptin, meat extract, yeast extract, corn steep liquid, casein hydrolysate, soybean powder, soybean powder hydrolysate, a variety of fermented bacterial bodies, and the digests thereof and the like.
As inorganic salts, the following can be used for example: potassium primary phosphate, potassium secondary phosphate, magnesium phosphate, magnesium sulfate, sodium chloride, ferrous phosphate, manganese sulfate, copper sulfate, calcium carbonate and the like. Culture will be conducted under aerobic conditions such as shaking or deep aerator agitating culture.
Culture temperature is preferably from 15-40 degrees Celsius. The period of time for culture is usually from five hours to seven days but is not limited thereto. The pH during the culture is kept from 3.0 to 9.0. The adjustment of the pH may be conducted by adding inorganic or organic acid or alkaline solution, urea, calcium carbonate, ammonia and the like. During the culture, antibiotics such as ampicillin or tetracycline or the like may be added as necessary.
When culturing a microorganism which has been transformed using an expression vector containing an inducible promoter, the culture medium may be optionally supplemented with an inducer. For example, when a microorganism, which has been transformed using an expression vector containing a lac promoter, is cultured, isopropyl-β-D-thiogalactopyranoside or the like may be added to the culture medium. When a microorganism, which has been transformed using an expression vector containing a trp promoter, is cultured, indole acrylic acid or the like may be added to the culture medium. A cell or an organ into which a gene has been introduced can be cultured in a large volume using a jar fermentor. Generally used medium for culture are used herein such as Murashige and Skoog (MS) medium, White medium, or these medium supplemented with auxin, cytokine or plant hormones and the like.
For example, when using an animal cell, mediums used for culturing the cell of the subject invention include, for example those generally used such as RMPI1640 medium [The Journal of the American Medical Association, 199, 519 (1967)], Eagle's MEM medium [Science, 122, 501 (1952)] DMEM medium [Virology, 8, 396 (1959)], 199 medium [Proceedings of the Society for the Biological Medicine, 73, 1 (1950)], or such a culture medium supplemented with fetal bovine serum or the like.
Culture is normally carried out for 1 to 7 days under conditions such as pH 6 to 8, 25 to 40° C., 5% CO 2 . An antibiotic, such as kanamycin, penicillin, streptomycin, or the like may be optionally added to the culture medium during cultivation.
A polypeptide of the present invention can be isolated or purified from a culture of a transformant, which has been transformed with a nucleic acid sequence encoding the polypeptide, using an ordinary method for isolating or purifying enzymes, which are well known and commonly used in the art. For example, when a polypeptide of the present invention is secreted outside a transformant for producing the polypeptide, the culture is subjected to centrifugation or the like to obtain a soluble fraction. A purified specimen can be obtained from the soluble fraction by a technique, such as solvent extraction, salting-out/desalting with ammonium sulfate or the like, precipitation with organic solvent, anion exchange chromatography with a resin (e.g., diethylaminoethyl (DEAE)-Sepharose, DIAION HPA-75 (Mitsubishi Chemical Corporation), etc.), cation exchange chromatography with a resin (e.g., S-Sepharose FF (Pharmacia), etc.), hydrophobic chromatography with a resin (e.g., buthylsepharose, phenylsepharose, etc.), gel filtration with a molecular sieve, affinity chromatography, chromatofocusing, electrophoresis (e.g., isoelectric focusing electrophoresis, etc.).
When the polypeptide of the present invention has been expressed and formed insoluble bodies within cells, the cells are harvested, pulverized, and centrifuged. From the resulting precipitate fraction, the polypeptide of the present invention is collected using a commonly used method. The insoluble polypeptide is solubilized using a polypeptide denaturant. The resulting solubilized solution is diluted or dialyzed into a denaturant-free solution or a dilute solution, where the concentration of the polypeptide denaturant is too low to denature the polypeptide. The polypeptide of the present invention is allowed to form a normal three-dimensional structure, and the purified specimen is obtained by isolation and purification as described above.
Purification can be carried out in accordance with a commonly used protein purification method (J. Evan. Sadler et al.: Methods in Enzymology, 83, 458). Alternatively, the polypeptide of the present invention can be fused with other proteins to produce a fusion protein, and the fusion protein can be purified using affinity chromatography using a substance having affinity to the fusion protein (Akio Yamakawa, Experimental Medicine, 13, 469-474 (1995)). For example, in accordance with a method described in Lowe et al., Proc. Natl. Acad. Sci., USA, 86, 8227-8231 (1989), Genes Develop., 4, 1288 (1990)), a fusion protein of the polypeptide of the present invention with protein A is produced, followed by purification with affinity chromatography using immunoglobulin G.
A fusion protein of the polypeptide of the present invention with a FLAG peptide is produced, followed by purification with affinity chromatography using anti-FLAG antibodies (Proc. Natl. Acad. Sci., USA, 86, 8227 (1989), Genes Develop., 4, 1288 (1990)).
The polypeptide of the present invention can be purified with affinity chromatography using antibodies which bind to the polypeptide. The polypeptide of the present invention can be produced using an in vitro transcription/translation system in accordance with a known method (J. Biomolecular NMR, 6, 129-134; Science, 242, 1162-1164; J. Biochem., 110, 166-168 (1991)).
The polypeptide of the present invention can also be produced by a chemical synthesis method, such as the Fmoc method (fluorenylmethyloxycarbonyl method), the tBoc method (t-buthyloxycarbonyl method), or the like, based on the amino acid information thereof. The peptide can be chemically synthesized using a peptide synthesizer (manufactured by Advanced ChemTech, Applied Biosystems, Pharmacia Biotech, Protein Technology Instrument, Synthecell-Vega, PerSeptive, Shimadzu, or the like).
The structure of the purified polypeptide of the present invention can be produced by methods commonly used in protein chemistry (see, for example, Hisashi Hirano. “Protein Structure Analysis for Gene Cloning”, published by Tokyo Kagaku Dojin, 1993). The physiological activity of a polypeptide of the present invention can be measured in accordance with a known measurement method.
(Method for Producing Variant Polypeptides)
Deletion, substitution or addition of an amino acid of the polypeptide of the present invention may be carried out by site directed mutagenesis, which was well known prior to the present application. Those with one or more amino acids deleted, substituted or added may be prepared in accordance with the methods described in: Molecular Cloning, A Laboratory Manual, Second Edition, Cold Spring Harbor Laboratory Press (1989), Current Protocols in Molecular Biology, Supplement 1-38, John Wiley & Sons (1987-1997), Nucleic Acids Research, 10, 6487(1982), Proc. Natl. Acad. Sci., USA, 79, 6409 (1982), Gene, 34, 315 (1985), Nucleic Acids Research, 13, 4431 (1985), Proc. Natl. Acad. Sci USA, 82, 488 (1985), Proc. Natl. Acad. Sci., USA, 81, 5662 (1984), Science, 224, 1431 (1984), PCT WO85/00817 (1985), Nature, 316, 601 (1985) and the like.
(Gene Therapy)
In certain embodiments, a nucleic acid comprising a sequence encoding an antibody or a functional derivative thereof is administered for the purpose of gene therapy for treating, inhibiting or preventing a disease or disorder related to abnormal expression and/or activity of a polypeptide used in the present invention. Gene therapy refers to a therapy performed by administering a nucleic acid, which has been expressed or is capable of being expressed, into subjects. In this embodiment of the present invention, a nucleic acid produces a protein encoded thereby and the protein mediates a therapeutic effect.
Any method available in the art for gene therapy may be used in accordance with the present invention. Illustrative methods are described below.
See the following review articles for gene therapy: Goldspiel et al., Clinical Pharmacy 12:488-505 (1993); Wu and Wu, Biotherapy 3:87-95 (1991); Tolstoshev, Ann. Rev. Pharmacol. Toxicol. 32:573-596 (1993); Mulligan, Science 260:926-932 (1993); and Morgan and Anderson, Ann. Rev. Biochem. 62:191-217 (1993); and May, TIBTECH 11(5):155-215 (1993). Generally known recombinant DNA techniques used for gene therapy are described in Ausubel et al. (eds.), Current Protocols in Molecular Biology, John Wiley & Sons, NY (1993); and Kriegler, Gene Transfer and Expression, A Laboratory Manual, Stockton Press, NY (1990).
(Demonstration of Therapeutic Activity or Preventive Activity)
The compounds or pharmaceutical compositions of the present invention are preferably tested in vitro, and then in vivo for the desired therapeutic or prophylactic activity, prior to use in humans. For example, in vitro assays to demonstrate the therapeutic or prophylactic utility of a compound or pharmaceutical composition include, the effect of a compound on a cell line or a patient tissue sample. The effect of the compound or composition on the cell line and/or tissue sample can be determined utilizing techniques known to those skilled in the art (including, but not limited to, cell lysis assays). In accordance with the present invention, in vitro assays which can be used to determine whether administration of a specific compound is indicated, include in vitro cell culture assays in which a patient tissue sample is grown in culture, and exposed to or otherwise administered a compound, and the effect of such compound upon the tissue sample is observed.
(Therapeutic/Prophylactic Administration and Composition)
The present invention provides methods of treatment, prevention and prophylaxis by administration to a subject of an effective amount of a component or pharmaceutical composition comprising the promoter of the present invention. In a preferable aspect, the component comprising a promoter may be substantially purified (for example, including the state where the effects are reduced, or a substance causing undesirable side effect is substantially free). Subjects may preferably be an animal including but not limited to: cattle, pigs, horses, chickens, cats, dogs and the like, and preferably primates, and most preferably humans.
When a nucleic acid molecule or polypeptide of the present invention is used as a medicament, the medicament may further comprise a pharmaceutically acceptable carrier. Any pharmaceutically acceptable carrier known in the art may be used in the medicament of the present invention.
Examples of a pharmaceutically acceptable carrier or a suitable formulation material include, but are not limited to, antioxidants, preservatives, colorants, flavoring agents, diluents, emulsifiers, suspending agents, solvents, fillers, bulky agents, buffers, delivery vehicles, and/or pharmaceutical adjuvants. Typically, a medicament of the present invention is administered in the form of a composition comprising a polypeptide or a polynucleotide or a variant or fragment thereof, or a variant or derivative thereof, or an agent capable of modulating any of these substances, with at least one physiologically acceptable carrier, excipient or diluent. For example, an appropriate vehicle may be injection solution, physiological solution, or artificial cerebrospinal fluid, which can be supplemented with other substances which are commonly used for compositions for parenteral delivery.
Acceptable carriers, excipients or stabilizers used herein preferably are nontoxic to recipients and are preferably inert at the dosages and concentrations employed, and preferably include phosphate, citrate, or other organic acids; ascorbic acid, α-tocopherol; low molecular weight polypeptides; proteins (e.g., serum albumin, gelatin, or immunoglobulins); hydrophilic polymers (e.g., polyvinylpyrrolidone); amino acids (e.g., glycine, glutamine, asparagine, arginine or lysine); monosaccharides, disaccharides, and other carbohydrates (glucose, mannose, or dextrins); chelating agents (e.g., EDTA); sugar alcohols (e.g., mannitol or sorbitol); salt-forming counterions (e.g., sodium); and/or nonionic surfactants (e.g., Tween, pluronics or polyethylene glycol (PEG)).
Examples of appropriate carriers include neutral buffered saline or saline mixed with serum albumin. Preferably, the product is formulated as a lyophilizate using appropriate excipients (e.g., sucrose). Other standard carriers, diluents, and excipients may be included as desired. Other exemplary compositions comprise Tris buffer of about pH 7.0-8.5, or acetate buffer of about pH 4.0-5.5, which may further include sorbitol or a suitable substitute therefor.
The medicament of the present invention may be administered orally or parenterally. Alternatively, the medicament of the present invention may be administered intravenously or subcutaneously. When systemically administered, the medicament for use in the present invention may be in the form of a pyrogen-free, pharmaceutically acceptable aqueous solution. The preparation of such pharmaceutically acceptable compositions, with due regard to pH, isotonicity, stability and the like, is within the skill of the art. Administration methods may be herein oral, parenteral administration (e.g., intravenous, intramuscular, subcutaneous, intradermal, to mucosa, intrarectal, vaginal, topical to an affected site, to the skin, etc.). A prescription for such administration may be provided in any formulation form. Such a formulation form includes liquid formulations, injections, sustained preparations, and the like.
The medicament of the present invention may be prepared for storage by mixing a sugar chain composition having the desired degree of purity with optional physiologically acceptable carriers, excipients, or stabilizers (Japanese Pharmacopeia ver. 14, or a supplement thereto or the latest version; Remington's Pharmaceutical Sciences, 18th Edition, A. R. Gennaro, ed., Mack Publishing Company, 1990; and the like), in the form of lyophilized cake or aqueous solutions.
The type and amount of a pharmaceutical agent used in the treatment method of the present invention can be easily determined by those skilled in the art based on information obtained by the method of the present invention (e.g., information relating to a disease) in view of the purpose of use, the target disease (type, severity, etc.), the subject's age, size, sex, and case history, the morphology and type of a site of a subject of administration, or the like. The frequency of subjecting a subject (patient) to the monitoring method of the present invention is also easily determined by those skilled in the art with respect to the purpose of use, the target disease (type, severity, etc.), the subject's age, size, sex, and case history, the progression of the therapy, and the like. Examples of the frequency of monitoring the state of a disease include once per day to once per several months (e.g., once per week to once per month). Preferably, monitoring is performed once per week to once per month with reference to the progression.
(Immune Therapy)
As used herein the term “vaccine” refers to a composition (for example, suspension or solution) comprising a usually infectious agent or a portion of an infectious agent, an agent (for example, gene sequence) which allows production of such an agent or portion, to induce an active immune response. Antigenic portions constituting vaccines may be a microorganism (such as a virus or bacteria or the like), a native product purified from such a microorganism, a synthetic product or genetically engineered proteins, peptides, polysaccharides or similar products and nucleic acid molecules comprising a nucleic acid sequence encoding such proteins. Vaccines express the effects thereof by causing a neutralizing antibody.
As used herein the term “gene vaccine” refers to a composition (for example, suspension or solution or the like) comprising an agent (typically nucleic acid molecule) which is expressed in the subject to be administered and whose expressed product has vaccine action. Typical genetic vaccines may be nucleic acid molecules comprising the nucleic acid sequence encoding a gene product having antigenicity (for example, vectors, plasmids, Naked DNA and the like).
As used herein, immunologic effects of the vaccines according to the present invention can be confirmed by using any method known in the art. Such a method includes, but is not limited to: for example, CTL precursor cell frequency analysis, ELISPOT method, tetramer method, realtime PCR method and the like. As an exemplary description for CTL precursor frequency analysis, peripheral lymphocyte or antigenic peptide and lymphocyte cultured in the presence of IL-2, were subjected to limitation dilution, and IL-2 and feeder cells were cultured under coexistence, and the wells having propagation were stimulated with vaccines or their candidates, and the presence or absence of IFN-γ production is measured using ELISA. Herein, positive wells are used to calculate the frequency of CTL precursor cells according to the Poisson Analysis, to evaluate efficacy of the vaccines. As used herein, the number of positive cells is the number of antigen-specific CTLs and the greater the number is, the greater the efficacy of the vaccine.
The present invention may be used as a cancer vaccine. In such a case cancer antigens may be incorporated as a foreign gene.
As used herein, the term “cancer antigen” refers to an antigen molecule which will be newly expressed in association with canceration of a normal cell. Such a cancer antigen includes, but is not limited to, for example:
(1) tumor virus derived antigens (for example, T antigens or the like from DNA type tumor virus such as adenovirus, polyoma virus, SV40 and the like). In RNA-type tumor virus of human or mouse, viral envelope proteins are expressed on the cellular surface;
(2) tumor specific transplantation antigen (TSTA); this antigen refers to a target antigen of a cancer cell of the same lineage, when the cancer cell is rejected as a result of formation of a specific immune response. Genetic mutations cause variant proteins in a cancer cell, which allows expression thereof on the cellular surface of the cancer cell by association with a molecule of major histocompatibility (MHC) antigen gene complex as peptide fragments, as in other intracellular normal proteins;
(3) tumor associated antigen (TAA): antigens which exhibit specific expression in association with canceration, although it is not necessarily specific to the cancer cell. For example, it corresponds to α-fetoprotein in liver cancer, carcinoembryonic antigen (CEA) in enteric cancer and the like. These are proteins which are originally present only in normal fetuses, and are not found in the tissues of an adult. However, these proteins are called oncofetal antigens as re-expression will occur with the canceration.
As used herein, any form of cancer antigen may be used, and in particular, a form of carcinoma-related antigen is preferably used. This is because it will be expressed on the surface of a cancer cell upon association with MHC.
As used herein, the term “adjuvant” refers to a substance which increases, or otherwise alters, immune response when mixed with immunogen administered thereinto. Adjuvants are classified in view of minerals, bacteria, plants, synthetic, or products of a host, for example.
As used herein, the term “pathogen” refers to an organism or agent which allows onset of a disease or a disorder to a host.
As used herein, the terms “prophylaxis”, “prophylactic” “prevention” and “prevent” refer to a treatment of a disease or a disorder, in which such a disease or disorder should not be caused prior to the actual onset thereof.
As used herein, the terms “therapy”, “treatment” and “treat” refer to a treatment in which in the case where such occurs, deterioration of such a disease or disorder is prevented, preferably, at least maintaining the status quo, more preferably, alleviation further more preferably, cleared.
The vaccines of the present invention are preferably tested in vitro, and then in vivo for the desired therapeutic or prophylactic activity, prior to use in humans. For example, in vitro assays to demonstrate the therapeutic or prophylactic utility of vaccines according to the present invention include testing the effect of a vaccine on a cell line or a patient tissue sample. The effect of the vaccines on the cell line and/or tissue sample can be determined utilizing techniques known to those of skill in the art (for example, immunological assay such as ELISA). In vivo tests include but are not limited to: for example, a method for testing whether a neutralizing antibody is raised.
As used herein the term “patient” or “subject” refers to an organism to which the treatment or composition of the present invention is applied. Preferably, the patient may be a human.
The present invention provides methods of treatment, inhibition and prophylaxis by administration to a subject of an effective amount of a gene vaccine of the present invention. In a preferred aspect, the compound is substantially purified (e.g., substantially free from substances that limit its effect or produce undesired side-effects).
As used herein, the term “administer” means that the polypeptides, polynucleotides or the like of the present invention or pharmaceutical compositions containing them are incorporated into the cells, tissue or body of an organism either alone or in combination with other therapeutic agents. Combinations may be administered either concomitantly (e.g., as an admixture), separately but simultaneously or concurrently; or sequentially. This includes presentations in which the combined agents are administered together as a therapeutic mixture, and also procedures in which the combined agents are administered separately but simultaneously (e.g., as through separate or the same mucosa into the same individual). “Combination” administration further includes the separate administration of one of the compounds or agents given first, followed by the second.
Administration of vaccines according to the present invention may be conducted in any manner, and preferably it is advantageous to use a needleless syringe. This is because it can administer without causing undue load to a patient.
As used herein the term “needleless syringe” refers to a medical device which transfers a drug solution into the skin by moving a piston by gas pressure or elasticity of an elastic member, thereby administering a drug component into subcutaneous or preferably into the cell's subcutaneous site.
Specifically, for example, Shimajet™ (manufactured by Shimadzu, inc.), Medi-Jector Vision™ (manufactured by Elitemedica), PenJet™ (manufactured by PenJet), which are commercially available. Gene gun (particle gun) refers to a medical and experimental device which allows in vivo gene introduction by accelerating high density particles such as gold or tungsten coated with DNA using gas pressure of helium or the like. Advantageous effects of gene guns include effective intracellular introduction of a low amount of DNA, and stable results have been obtained with different operators.
Specifically, for example, Helios Gene Gun from Bio-Rad, USA is commercially available.
As used herein, the term “instructions” refers to a description of the method of the present invention for a person who performs administration, such as a medical doctor, a patient, or the like. Instructions state when to administer a medicament of the present invention, such as immediately after or before radiation therapy (e.g., within 24 hours, etc.). The instructions are prepared in accordance with a format defined by an authority of a country in which the present invention is practiced (e.g., Health, Labor and Welfare Ministry in Japan, Food and Drug Administration (FDA) in the U.S., and the like), explicitly describing that the instructions are approved by the authority. The instructions are so-called package insert and are typically provided in paper media. The instructions are not so limited and may be provided in the form of electronic media (e.g., web sites, electronic mails, and the like provided on the Internet).
The judgment of termination of treatment or prevention with a method of the present invention may be supported by the result of an antibody raised using a commercially available assay or device.
The present invention also provides a pharmaceutical package or kit comprising containers loaded with one or more pharmaceutical compositions according to the present invention. A notice in a form defined by a government agency which regulates the production, use or sale of pharmaceutical products or biological products may be arbitrarily attached to such a container, representing the approval of the government agency relating to production, use or sale with respect to administration to humans.
(General Techniques Used Herein)
Techniques used herein are within the technical scope of the present invention unless otherwise specified. These techniques are commonly used in the fields of sugar chain science, fluidics, microfabrication, organic chemistry, biochemistry, genetic engineering, molecular biology, microbiology, genetics, and their relevant fields. The techniques are sufficiently well described in documents described below and other documents mentioned herein.
Microfabrication is described in, for example, Campbell, S. A. (1996), The Science and Engineering of Microelectronic Fabrication, Oxford University Press; Zaut, P. V. (1996), Micromicroarray Fabrication: a Practical Guide to Semiconductor Processing, Semiconductor Services; Madou, M. J. (1997), Fundamentals of Microfabrication, CRC1 5 Press; Rai-Choudhury, P. (1997), Handbook of Microlithography, Micromachining & Microfabrication: Microlithography; and the like, the relevant portions of which are hereby incorporated by reference.
Molecular biology techniques, biochemistry techniques, and microbiology techniques used herein are well known and commonly used in the art, and are described in, for example, Maniatis, T. et al. (1989), Molecular Cloning: A Laboratory Manual, Cold Spring Harbor and its 3rd Ed. (2001); Ausubel, F. M. et al. eds, Current Protocols in Molecular Biology, John Wiley & Sons Inc., NY, 10158 (2000); Innis, M. A. (1990), PCR Protocols: A Guide to Methods and Applications, Academic Press; Innis, M. A. et al. (1995), PCR Strategies, Academic Press; Sninsky, J. J. et al. (1999), PCR Applications: Protocols for Functional Genomics, Academic Press; Gait, M. J. (1985), Oligonucleotide Synthesis: A Practical Approach, IRL Press; Gait, M. J. (1990), Oligonucleotide Synthesis: A Practical Approach, IRL Press; Eckstein, F. (1991), Oligonucleotides and Analogues: A Practical Approach, IRL Press; Adams, R. L. et al. (1992), The Biochemistry of the Nucleic Acids, Chapman & Hall; Shabarova, Z. et al. (1994), Advanced Organic Chemistry of Nucleic Acids, Weinheim; Blackburn, G. M. et al. (1996), Nucleic Acids in Chemistry and Biology, Oxford University Press; Hermanson, G. T. (1996), Bioconjugate Techniques, Academic Press; Method in Enzymology 230, 242, 247, Academic Press, 1994; Special issue, Jikken Igaku (Experimental Medicine) “Idenshi Donyu & Hatsugenkaiseki Jikkenho (Experimental Method for Gene introduction & Expression Analysis)”, Yodo-sha, 1997; and the like. Relevant portions (or possibly the entirety) of each of these publications are herein incorporated by reference.
DESCRIPTION OF PREFERRED EMBODIMENTS
Hereinafter, the present invention will be described by way of embodiments. Embodiments described below are provided only for illustrative purposes. Accordingly, the scope of the present invention is not limited by the embodiments except as by the appended claims. It will be clearly appreciated by those skilled in the art that variations and modifications can be made without departing from the scope of the present invention with reference to the specification.
In an aspect, the present invention provides MIE promoters of HHV (including HHV6A and HHV6B, in particular HHV6B) and HHV7, and/or U95 promoter of HHV7. In particular, it has been discovered that MIE promoter of HHV6B, MIE promoter of HHV7, and U95 promoter of HHV7 are surprisingly enhanced in selectivity to lymphocytes in comparison to IE promoters of HCMV. In particular, adhesive cells (293 cells, Vero cells and the like) only showed one hundredth the activity of that of HCMV IE promoter, whereas in lymphoid cells such as SupT1, U937 and the like, a several fold increase in expression efficiency has been obtained. Such a high level of selectivity or specificity elucidated that it can be applied to the development of a pharmaceutical which is targeted to DNA vaccines, gene therapy, in particular, to lymphocytes. Moreover, in an expression system in vivo, since activities are diminished even in the case of CMV promoters which have potent activity, due to the action of methylase, it is understood that the promoter of the present invention may be used to secure expression amount in vivo in blood cells or lymphocyte cells. In genetic diseases, gene therapy of cancer, retroviruses are generally used, however, LTR activity is not so potent, as a promoter, the introduction of the promoter of the present invention upstream of the gene to be expressed allows potent expression in blood cell lineage cells. The present invention is also useful in gene therapy targeting blood cell diseases such as leukemia and the like. Furthermore, RNAi is used as a method of knocking out gene expression, and the promoter of the present invention is used as a promoter for hair-pin type RNA expression vectors, allowing more efficient effects of inhibition of expression in the blood cell lineage. Macrophages or dendritic cells or the like are purified from native peripheral blood using flow cytometry, and these cells are transfected with plasmids constructed so as to express cancer specific antigen or tumor necrosis factor (TNF) or the like under the control of the promoter of the present invention, and reintroduced to the original body after confirmation of expression of cancer antigen, thereby practicing the gene therapy of cancer as a result of efficient activation of tumor antigen specific CTL via Glass I-HLA.
In one embodiment, the promoters of the present invention may have a length of at least 8 contiguous nucleotides. Preferably, the promoter of the present invention includes at least the R3 region or the functional variant thereof, amongst the sequence set forth in SEQ ID NO: 1. More preferably, the promoter of the present invention includes at least the sequence of −574 to −427 from the transcription initiation point of the SEQ ID NO: 1; more preferably, at least the sequence of −1051 to −427 from the transcription initiation point of the SEQ ID NO: 1. This is because it is predicted that these regions have regions having enhancer activity.
In one embodiment, the promoter of the present invention comprises NF-κB and AP-1 motives.
In a preferable embodiment, the promoter of the present invention comprises a sequence set forth in SEQ ID NO: 1, and more preferably consists essentially of the sequence set forth in SEQ ID NO: 1.
In one embodiment, the promoter of the present invention comprises: (a) a polynucleotide having the base sequence set forth in SEQ ID NO: 1, or the base sequence corresponding thereto or a fragment sequence thereof; (b) a polynucleotide of an allelic variant of the base sequence set forth in SEQ ID NO: 1 or the base sequence corresponding thereto or a fragment sequence thereof; (c) a polynucleotide which hybridizes a polynucleotide of any of (a) or (b) and has a biological activity thereof; or (d) a polynucleotide which consists of the base sequence of any of (a) to (c) or a complement sequence thereof with at least 70% identity, and has a biological activity thereof. As used herein, the biological activity may be promoter and/or enhancer activities but is not limited thereto. Promoter and enhancer activities may be measured using well known technology in the art, and such a technology is described herein and exemplified in the Examples.
In one preferred embodiment, the number of substitutions, additions and deletions described in (a) through (d) above may be limited to, for example, preferably 50 or less, 40 or less, 30 or less, 20 or less, 15 or less, 10 or less, 9 or less, 8 or less, 7 or less, 6 or less, 5 or less, 4 or less, 3 or less, or 2 or less. The number of substitutions, additions and deletions is preferably small, but may be large as long as the biological activity is maintained (preferably, the activity is similar to or substantially the same as that of HHV6B MIE promoter).
In a preferred embodiment, the identity to any one of the polynucleotides described in (a) to (d) above or a complementary sequence thereof may be at least about 80%, more preferably at least about 90%, even more preferably at least about 98%, and most preferably at least about 99%.
In a preferred embodiment, the nucleic acid molecule of the present invention may have a length of at least 8 contiguous nucleotides. The appropriate nucleotide length of the nucleic acid molecule of the present invention may vary depending on the purpose of use of the present invention. More preferably, the nucleic acid molecule of the present invention may have a length of at least 10 contiguous nucleotides, even more preferably at least 15 contiguous nucleotides, and still even more preferably at least 20 contiguous nucleotides. These lower limits of the nucleotide length may be present between the above-specified numbers (e.g., 9, 11, 12, 13, 14, 16, and the like) or above the above-specified numbers (e.g., 21, 22, . . . 30, and the like). The upper limit of the length of the polypeptide of the present invention is not limited as long as it can be used for the intended purpose (e.g. promoter). Stringency may be high, or intermediate or low, and the level of stringency may be appropriately determined according to the circumstances.
In a different embodiment, the promoter according to the present invention may have a length of at least 8 contiguous nucleotides. Preferably, the promoter of the present invention includes at least the R2 region or the functional variant thereof, amongst the sequence set forth in SEQ ID NO; 2. More preferably, the promoter of the present invention includes at least the sequence of −388 to +22 from the transcription initiation point of the SEQ ID NO: 2; more preferably, at least the sequence of −493 to +22 from the transcription initiation point of the SEQ ID NO: 2. This is because it is predicted that these regions contain regions having enhancer activity.
In one embodiment, the promoter according to the present invention includes NF-κB motifs (−464 to −478 and −359 to −350 in SEQ ID NO: 2).
In a preferable embodiment, the promoter of the present invention comprises, the sequence set forth in SEQ ID NO: 2, and more preferably, consists essentially of the sequence set forth in SEQ ID NO; 2.
In one embodiment, the promoter of the present invention comprises: (a) a polynucleotide having the base sequence set forth in SEQ ID NO: 2, or the base sequence corresponding thereto or a fragment sequence thereof; (b) a polynucleotide of an allelic variant of the base sequence set forth in SEQ ID NO: 2 or the base sequence corresponding thereto or a fragment sequence thereof; (c) a polynucleotide which hybridizes a polynucleotide of any of (a) or (b) and has a biological activity thereof; or (d) a polynucleotide which consists of the base sequence of any of (a) to (c) or a complement sequence thereof with at least 70% identity, and has a biological activity thereof. As used herein, the biological activity may be promoter and/or enhancer activities but is not limited thereto. Promoter and enhancer activities may be measured using well known technology in the art, and such a technology is described herein and exemplified in the Examples.
In one preferred embodiment, the number of substitutions, additions and deletions described in (a) through (d) above may be limited to, for example, preferably 50 or less, 40 or less, 30 or less, 20 or less, 15 or less, 10 or less, 9 or less, 8 or less, 7 or less, 6 or less, 5 or less, 4 or less, 3 or less, or 2 or less. The number of substitutions, additions and deletions is preferably small, but may be large as long as the biological activity is maintained (preferably, the activity is similar to or substantially the same as that of HHV7 MIE promoter).
In a preferred embodiment, the identity to any one of the polynucleotides described in (a) to (d) above or a complementary sequence thereof may be at least about 80%, more preferably at least about 90%, even more preferably at least about 98%, and most preferably at least about 99%.
In a preferred embodiment, the nucleic acid molecule of the present invention may have a length of at least 8 contiguous nucleotides. The appropriate nucleotide length of the nucleic acid molecule of the present invention may vary depending on the purpose of use of the present invention. More preferably, the nucleic acid molecule of the present invention may have a length of at least 10 contiguous nucleotides, even more preferably at least 15 contiguous nucleotides, and still even more preferably at least 20 contiguous nucleotides. These lower limits of the nucleotide length may be present between the above-specified numbers (e.g., 9, 11, 12, 13, 14, 16, and the like) or above the above-specified numbers (e.g., 21, 22, . . . 30, and the like). The upper limit of the length of the polypeptide of the present invention is not limited as long as it can be used for the intended purpose (e.g. promoter). Stringency may be high, or intermediate or low, and the level of stringency may be appropriately determined according to the circumstances.
In another embodiment, the promoter of the present invention may have a length of at least 8 contiguous nucleotides. Preferably, the promoter of the present invention includes at least the R2 region or the functional variant thereof, amongst the sequence set forth in SEQ ID NO; 12. More preferably, the promoter of the present invention includes at least the sequence of −379 to +16 from the transcription initiation point of the SEQ ID NO: 12; more preferably, at least the sequence of −484 to +16 from the transcription initiation point of the SEQ ID NO: 12. This is because it is predicted that these regions containing regions having enhancer activity.
In one embodiment, the promoter according to the present invention includes NF-κB motifs (−478 to −469 and −373 to −364 in SEQ ID NO: 12).
In a preferable embodiment, the promoter of the present invention comprises, the sequence set forth in SEQ ID NO: 12, and more preferably, consists essentially of the sequence set forth in SEQ ID NO; 12.
In one embodiment, the promoter of the present invention comprises: (a) a polynucleotide having the base sequence set forth in SEQ ID NO: 12, or the base sequence corresponding thereto or a fragment sequence thereof; (b) a polynucleotide of an allelic variant of the base sequence set forth in SEQ ID NO: 12 or the base sequence corresponding thereto or a fragment sequence thereof; (c) a polynucleotide which hybridizes a polynucleotide of any of (a) or (b) and has a biological activity thereof; or (d) a polynucleotide which consists of the base sequence of any of (a) to (c) or a complement sequence thereof with at least 70% identity, and has a biological activity thereof. As used herein, the biological activity may be promoter and/or enhancer activities but is not limited thereto. Promoter and enhancer activities may be measured using well known technology in the art, and such a technology is described herein and exemplified in the Examples.
In one preferred embodiment, the number of substitutions, additions and deletions described in (a) through (d) above may be limited to, for example, preferably 50 or less, 40 or less, 30 or less, 20 or less, 15 or less, 10 or less, 9 or less, 8 or less, 7 or less, 6 or less, 5 or less, 4 or less, 3 or less, or 2 or less. The number of substitutions, additions and deletions is preferably small, but may be large as long as the biological activity is maintained (preferably, the activity is similar to or substantially the same as that of the HHV7 U95 promoter).
In a preferred embodiment, the identity to any one of the polynucleotides described in (a) to (d) above or a complementary sequence thereof may be at least about 80%, more preferably at least about 90%, even more preferably at least about 98%, and most preferably at least about 99%.
In a preferred embodiment, the nucleic acid molecule of the present invention may have a length of at least 8 contiguous nucleotides. The appropriate nucleotide length of the nucleic acid molecule of the present invention may vary depending on the purpose of use of the present invention. More preferably, the nucleic acid molecule of the present invention may have a length of at least 10 contiguous nucleotides, even more preferably at least 15 contiguous nucleotides, and still even more preferably at least 20 contiguous nucleotides. These lower limits of the nucleotide length may be present between the above-specified numbers (e.g., 9, 11, 12, 13, 14, 16, and the like) or above the above-specified numbers (e.g., 21, 22, . . . 30, and the like). The upper limit of the length of the polypeptide of the present invention is not limited as long as it can be used for the intended purpose (e.g. promoter). Stringency may be high, or intermediate or low, and the level of stringency may be appropriately determined according to the circumstances.
In another aspect, the present invention provides a nucleic acid construct comprising a promoter of the present invention (MIE promoter of HHV6, MIE promoter of HHV7, U95 promoter of HHV7 and the like). Such a nucleic acid construct has a property of inducing expression in a lymphocyte specific manner, and the utility thereof is high, and exhibits unexpectedly high selectivity in comparison to human cytomegalovirus (HCMV) IE promoter.
Accordingly, in one embodiment, the nucleic acid construct of the present invention comprises a sequence encoding a foreign gene having a different origin than the promoter of the present invention, with a sequence of the present invention operably linked thereto.
Such a foreign gene includes, but is not limited to, for example, those encoding an RNAi molecule, drug resistance, a recessive gene to be deleted, a selective marker and the like.
Preferably, selective markers used in the present invention are those allowing selection in a medium for the host into which the nucleic acid construct is introduced, and for example, these selective markers may be those allowing visible selection in the host into which the nucleic acid construct is introduced, and exemplifies hypoxanthine guanine transferase (hprt) or a fluorescent marker selected from the group consisting of green fluorescent protein (GFP), cyan fluorescent protein (CFP), yellow fluorescent protein (YFP) and red fluorescent protein (dsRed) and the like.
Preferably, selective markers included in the nucleic acid construct of the present invention are advantageously those substantially exhibiting no toxicity against the host into which the nucleic acid construct is introduced according to the present invention. This is because, when using the present invention for the purpose of therapy or prevention, adverse effects should be preferably none.
Those to be included in the nucleic acid construct according to the present invention include for example, a recessive gene to be deleted. As used herein, a recessive gene to be deleted refers to any recessive gene which exhibits diseased condition when deleted, and includes, but is not limited to, for example: ADA gene (which is related to severe combined immunodeficiency (SCID)), PNP gene (severe combined immunodeficiency (SCID)), γ c chain gene (which is related to severe combined immunodeficiency (SCID)), TAP gene (which is related to MHC I deficiency), MHC II gene (which is related to MHC II deficiency), X-linked WASP (which is related to Wiskott-Aldrich syndrome), CD40 ligand (which is related to X-linked high IgM syndrome), PI3K-like gene (which is related to granuloma telangiectaticum) and DNA helicase (which is related to Bloom's syndrome), and the like.
In a preferable embodiment, drugs to be included in the nucleic acid construct of the present invention may be proteineous agents such as a cytokine, a chemokine, a growth factor, a protein hormone, and a peptide hormone such as IFN-α, IFN-γ, IL-2, IL-12, G-CSF, GM-CSF and the like.
In one embodiment, in the nucleic acid construct of the present invention the promoter induces specific expression of the foreign gene in a hemocyto-lineage cell, in particular, in a T cell.
In another aspect, the present invention provides an expression vector comprising the nucleic acid construct according to the present invention. Such an expression vector may include elements essential to expression, which may not exist in the nucleic acid construct of the present invention, for example, terminator, enhancer sequences, in an operably linked manner, which allow expression in the host.
In another preferable embodiment, selective markers may be immortalizing genes (for example bcl-2). Alternatively, selective markers may be hypoxanthine guanine phosphoribosyl transferase (hprt), a gene encoding a toxic product, a toxic gene product depending on a condition in combination with a suicide substrate (for example, herpes simplex virus thymidine kinase (HSV-TK) in combination with acyclovir.
In another aspect, the present invention provides a cell comprising the nucleic acid construct according to the present invention. Such a cell, in the case of a lymphocyte, promotes the expression of a protein encoding a foreign gene.
Preferably, it may be advantageous that the cell of the present invention is heterogenous to the promoter sequence of the present invention. It is one of the surprising effects to have promoter activity even if the cell is heterogenous. A method for introducing a nucleic acid into a cell used in the present invention is well known in the art, and described in detail hereinabove. Alternatively, such a cell may be identified by screening a cell comprising the nucleic acid molecule in a sample comprising the same. The cell comprising the nucleic acid molecule according to the present invention may preferably be in an undifferentiated state. The cells expressing the nucleic acid molecule of the present invention is usually in a state of undifferentiation. Accordingly, a cell into which such a nucleic acid molecule has been introduced so as to be expressed in a controllable manner, may be controlled with respect to the undifferentiated state. Alternatively, such a cell may be used to produce a large amount of the nucleic acid according to the present invention. Such production methods are well known in the art and are described in the literature described herein.
In another aspect, the present invention provides a tissue comprising the nucleic acid construct according to the present invention. Such a nucleic acid sequence is preferably operably linked to a control sequence. Such an organ may be an animal tissue, or a tissue of a different organism such as a plant. Alternatively, such a tissue is used to produce a nucleic acid molecule according to the present invention in a large amount. Such a production method is well known in the art, and described in the reference described herein.
In another aspect, the present invention provides an organ comprising the nucleic acid construct according to the present invention. Such a nucleic acid sequence is preferably operably linked to a control sequence. Such an organ may be an animal organ, or an organ of a different organism such as a plant. Alternatively, such an organ is used to product a nucleic acid molecule according to the present invention in a large amount. Such a production method is well known in the art, and described in the reference described herein.
In another aspect, the present invention provides an organism comprising the nucleic acid construct according to the present invention. Such an organism is used to product a nucleic acid molecule according to the present invention in a large amount. Such a production method is well known in the art, and described in the reference described herein.
In another aspect, the present invention provides a pharmaceutical composition comprising the promoter according to the present invention. As used herein, antigen used may be any proteins desired to raise immune response in a host. Such antigens include, but are not limited to, for example, cancer antigen and the like. Accordingly, the pharmaceutical composition according to the present invention may preferably be DNA vaccine.
In another aspect, the present invention provides a pharmaceutical composition for treating a disease, disorder or condition in which a lymphocyte-specific treatment is desired, which comprises the promoter according to the present invention, and a nucleic acid sequence for the treatment. As used herein, the target of the pharmaceutical composition may appropriately be any diseases, disorders, conditions and the like desired to have lymphocyte specific treatment, and are exemplified by acquired immunodeficiency syndromes. Acquired immunodeficiency syndromes include, severe combined immunodeficiency (SCID), MHC I deficiency, MHC II deficiency, Wiskott-Aldrich syndrome, X-linked high IgM syndrome, granuloma telangiectaticum, Bloom's syndrome and the like. Although not wishing to be bound by theory, acquired immunodeficiency syndrome is caused by some deficiency in a recessive gene (which is herein also called a recessive gene to be deleted). It is thus possible to carry out somatic gene therapy in which this gene to be deleted is introduced to bone marrow cells taken from a patient then the cells are reintroduced into the patient. In this regard, the HHV6B MIE promoter of the present invention is likely employed to increase the gene expression efficiency in a cell differentiated into T cell or macrophage and the like. Introduction of such a gene construct is, for example, possible by using retrovirus and the like.
In a preferable embodiment, the nucleic acid sequences for the treatment include a sequence selected from the group consisting of those encoding cytokines, chemokines, growth factors, protein hormones, peptide hormones, ribozymes and siRNA
(HIV-1 gp41:
(SEQ ID NO: 33)
AATAAGACAGGGCTTGGAAAGACACTTTCCAAGCCCTGTCTTATTTTT/
HIV-1 tat:
(SEQ ID NO: 34)
AAGCATCCAGGAAGTCAGCCTACAAGGCTGACTTCCTGGATGCTTTTT/
HTLV-1 tax:
(SEQ ID NO: 35)
GAACATTGGTGAGGAAGGCACAGCCTTCCTCACCAATGTTCTTTTT).
In another aspect, the present invention provides a method for expressing a protein in a lymphocyte specific manner, comprising the steps of: A) preparing a nucleic acid construct in which the promoter according to the present invention is operatively linked to a nucleic acid sequence encoding the protein; and B) placing the nucleic acid construct under a condition in which the promoter induces the expression of the nucleic acid sequence encoding the protein.
In another aspect, the present invention provides a kit for expressing a protein in a lymphocyte specific manner, comprising: A) a nucleic acid construct in which the promoter according to the present invention is operatively linked to a nucleic acid sequence encoding the protein; and B) means for placing the nucleic acid construct under a condition in which the promoter induces the expression of the nucleic acid sequence encoding the protein.
In another aspect, the present invention further provides a kit for expressing a protein in a lymphocyte specific manner, comprising: A) the promoter according to the present invention; and B) means for producing a nucleic acid construct in which the promoter is linked to a nucleic acid sequence encoding the protein.
In another aspect, the present invention further provides a method for treating or preventing a disease, disorder or condition which requires the expression of a protein in a lymphocyte specific manner, comprising the steps of: A) producing a nucleic acid construct in which the promoter according to the present invention is linked to a nucleic acid sequence encoding the protein; and B) placing the nucleic acid construct under a condition in which the promoter induces the expression of the nucleic acid sequence encoding the protein.
In another aspect, the present invention further provides a kit for treating or preventing a disease, disorder or condition which requires the expression of a protein in a lymphocyte specific manner, comprising: A) a nucleic acid construct in which the promoter according to the present invention is linked to a nucleic acid sequence encoding the protein; and B) means for placing the nucleic acid construct under a condition in which the promoter induces the expression of the nucleic acid sequence encoding the protein.
In another aspect, the present invention further provides a kit for treating or preventing a disease, disorder or condition which requires the expression of a protein in a lymphocyte specific manner, comprising: A) the promoter according to the present invention; and B) means for producing a nucleic acid construct in which the promoter is linked to a nucleic acid sequence encoding the protein.
In another aspect, the present invention further provides a method for producing a protein, comprising the steps of: A) preparing a nucleic acid construct in which the promoter according to the present invention is linked to a nucleic acid sequence encoding the protein; and B) placing the nucleic acid construct under a condition in which the promoter induces the expression of the nucleic acid sequence encoding the protein.
In another aspect, the present invention further provides a kit for producing a protein, comprising: A) a nucleic acid construct in which the promoter according to the present invention is linked to a nucleic acid sequence encoding the protein; and B) means for placing the nucleic acid construct under a condition in which the promoter induces the expression of the nucleic acid sequence encoding the protein.
In another aspect, the present invention further provides a kit for producing a protein, comprising: A) the promoter according to the present invention; and B) means for producing a nucleic acid construct in which the promoter is linked to a nucleic acid sequence encoding the protein.
In another aspect, the present invention further provides use of the promoter according to the present invention, for manufacture of a pharmaceutical composition for treating or preventing a disease, disorder or condition which requires the expression of a protein in a lymphocyte specific manner.
All scientific literature, patents, published patent applications and publications cited herein are incorporated by reference as if set forth fully herein.
The preferred embodiments of the present invention have been heretofore described for a better understanding of the present invention. Hereinafter, the present invention will be described by way of examples. Examples described below are provided only for illustrative purposes. Accordingly, the scope of the present invention is not limited except as by the appended claims.
EXAMPLES
Handling of animals used in the following Examples are in accordance with the provisions set forth in Osaka University.
Example 1
Search for HHV6B Promoters and Development of DNA Vaccines
With respect to promoters of immediate early protein of HHV-6 (9U, 20U, MIE, U95, MIE/3K, U95/3K, which are different in size), the activity thereof was compared to that of cytomegalovirus (CMV) promoter. With respect to methods, the respective promoter regions were inserted upstream of the luciferase gene of pGL3-Basic Vector (Promega), which were transfected with the respective cells to compare the activity thereof using luciferase activity as reference. Hereinafter, the details of materials and methods are described.
(Materials and Methods)
(Outline)
The promoter region of MIE gene of HHV-6B (about 1.2 kbp) was cloned, which was linked to an outer membrane glycoprotein of Japan encephalitis virus Beijing-1 strain cDNA downstream thereof to construct the plasmid p9u/JEVenv. Green fluorescence protein expression plasmid pEGFP-N1 used was commercially available (available from Clontech).
It was constructed using a plasmid (pcDNA3.1/JEVenv) as reference in which JEVenv was linked downstream of HCMV-IE promoter of pcDNA3.1Zeo+ vector. Green fluorescence protein expression plasmid pEGFP-N1 used was commercially available (available from BD Biosciences). Furthermore, luciferase expression plasmid used herein was that which has already been constructed (pGL3-Basic; available from Promega).
These plasmids were introduced to the following cells: 293 cell (derived from human kidney), Vero cell (derived from simian kidney), SupT1 cell (derived from human T lymphocyte), U937 cell (derived from human monocyte) and the like (these cells are available from American Type Culture Collection (ATCC), RIKEN Cell Bank, Gene banks and the like). The expression of outer membrane glycoprotein in a cell was studied using indirect fluorescence antibody method using anti-JEV polyclonal antibody, and Western blot with cell extract thereof.
HHV-6MIE promoter region was inserted upstream of firefly luciferase gene of luciferase vector pGL3-Basic (Promega) to form p9u, which was used to prepare truncated mutants by removing bases by Mung Bean Exonuclease from upstream of MIE promoter.
Vero cell was transfected with these truncated mutants and Renilla luciferase expression plasmid for transfection efficiency correction (phRL-SV40) by the lipofection method. Cells were collected 24 hours after the transfection, and cell lysis solution was added thereto. Thereafter, luminescent level was measured in the firefly luciferase and Renilla luciferase in the lysate. In order to correct the efficiency of transfection, the luminescence level of the firefly luciferase was divided by that of Renilla luciferase.
1) Cells—The Following Eight Types of Cell Lines were Used for Promoter Activity Measurement.
(1) Vero cell (derived from simian kidney)
(2) HEL cell (derived from human embryonic fibroblast cell)
(3) L929 cell (derived from murine fibroblast cell)
(4) 293 cell (derived from human kidney)
(5) U373 cell (derived from human glioma)
(6) THP-1 cell (derived from human monocyte)
(7) SupT1 cell (derived from human T cell)
(8) U937 cell (derived from human monocyte)
(These cells are available from American Type Culture Collection (ATCC)).
2) Plasmids for the Measurement of Promoter Activity
In order to measure promoter activity, pGL3-Basic (Promega) having firefly luciferase gene was used. This plasmid has no promoter sequence or enhancer sequence derived from eukaryotic cells, a variety of base sequences are introduced upstream of the luciferase gene, and the amount of luciferase expressed is measured to allow measurement of the promoter activity of the inserted sequence.
3) Promoter Sequence with pGL3-Basic Incorporated Therein
For measurement, as described below, HHV-6MIE promoter region, the promoter region of U95 gene, an immediate early gene of HHV-6 and HCMV MIE promoter region as commercially available expression vectors were used.
HHV-6 promoter region was used after proliferating by PCR and having inserted into pGL3-Basic.
(1) 20u [one with HHV-6MIE promoter region (139381←140624:1243 bp) inserted thereinto] (SEQ ID NO: 5)
(2) 9u [one with HHV-6MIE promoter region (139381←140427:1046 bp) inserted thereinto] (SEQ ID NO: 6)
(3) MIE [one with HHV-6MIE promoter region (139457←140211:754 bp) inserted thereinto] (SEQ ID NO: 7)
(4) U95 [one with HHV-6 U95 gene promoter region (141823→142578:756 bp) inserted thereinto] (SEQ ID NO: 8)
(5) CMV [one with HCMV MIE promoter excised from commercially available expression vector (pcDNA3.1) inserted thereinto: 750 bp] (SEQ ID NO: 9)
(6) MIE/3K [one with HHV-6MIE promoter region (139443←142578:3136 bp) inserted thereinto] (SEQ ID NO: 10)
(7) U95/3K [one with HHV-6MIE promoter region (139443→142578:3136 bp) inserted thereinto] (SEQ ID NO: 11), as a control, intact pGL3-Basic with no base sequence inserted was used.
Furthermore, a variety of deletion variants were produced. These schematic figures are shown in FIG. 5 . As variants, the following products were prepared as shown in FIG. 5 .
(1) 9u: −1051 to +1 (SEQ ID NO: 5)
(2) 9u-d2-7: −814 to +1 (SEQ ID NO: 17)
(3) 9u-d1-4: −574 to +1 (SEQ ID NO: 18)
(4) 9u-d1-5: −427 to +1 (SEQ ID NO: 19)
(5) 9u-d1-7: −350 to +1 (SEQ ID NO: 20)
(6) 9u-d3-7: −276 to +1 (SEQ ID NO: 21)
(7) 9u-d5: −240 to +1 (SEQ ID NO: 22)
(8) 9u-d6: −212 to +1 (SEQ ID NO: 23)
(9) 9u-d7: −116 to +1 (SEQ ID NO: 24)
(10) 9u-d8: −77 to +1 (SEQ ID NO: 25)
4) Transfection of a Cell with a Plasmid
Transfection was conducted with Lipofection method using SuperFect (QIAGEN).
In order to correct transfection efficiency, expression plasmids of β-galactosidase (pCH110, Pharmacia) were simultaneously introduced to a cell, and β-galactosidase activity was measured. pCH110 expresses β-galactosidase under control of the early promoter of SV40.
pGL3 construct (8 μl) and pCH110 (0.2 μl) were mixed together and Superfect reagent (8 μl) was added thereto to conduct transfection.
5) Measurement of Luciferase Activity
Luciferase activity was measured using Luciferase Assay System (Promega).
pGL3 construct and pCH110 were cotransfected, and 48 hours later, the cells were recovered. After twice washing with PBS, it was dissolved into 150 μL of cell lysis solution. One hundred μL of luciferase substrate solution was added to the cell lysis solution supernatant (20 μL), and thirty seconds later, luminescence was measured with a luminometer.
6) Measurement of β-Galactosidase Activity
B-galactosidase activity was measured using β-gal reporter system (Clontech). To twenty μL of cell lysis solution prepared in a similar manner as in the luciferase activity measurement was added 100 μL of luminescent substrate solution, and luminescence was measured after one hour using a luminometer.
7) Measurement of Promoter Activity Under Conditions where Cells were Activated with TPA
The plasmids were transfected with Vero cells and L929 cells, and 24 hours later, the cultures were conducted in the presence and absence of TPA (25 ng/ml) for an additional 24 hours. Thereafter, the cells were collected, and measured for the activity of luciferase and β-galactosidase.
(Results)
1) Promoter Activity of the HHV-6 MIE Region:
Promoter activity of HHV-6 MIE region and promoter activity of HCMV MIE showed different behaviour in endothelial adhesive cells and lymphocyte cells.
(1) Comparison of Promoter Activities in Adhesive Cells ( FIG. 1 )
The promoter sequence of HHV-6MIE had weaker activity than HCMV in adhesive cells, with some promoter activity. The promoter of U95, a HHV-6 immediate early gene, showed little activity. On the other hand, HCMV MIE promoter showed about 10 to 50 fold more activity than that of HHV-6 MIE promoter in adhesive cells. In particular, in HEL cells and U373 cells, HCMV proliferation competent cells, it showed potent activity.
With respect to the promoter activity of the HHV-6 MIE region, those having the promoter region from 0.7 kb to 1.2 kb in length showed substantially the same activity, but reduction in the activity was recognized in the sequence of 3 kb.
(2) Comparison of Promoter Activities in Lymphocyte Cells ( FIG. 2 )
In lymphocyte cells which are proliferation competent cells of HHV-6, the HHV-6 MIE region showed about ten times higher promoter activity than HCMV. In particular, it showed potent activity in THP-1 and U937 which are cell lines of monocytic macrophages. HCMV MIE promoter did not exhibit so strong activity in lymphocytes.
The promoter activity of the HHV-6 MIE region increased the activity thereof in accordance with the length from 0.7 kb to 1.2 kb in the promoter region, however, the length of 3 kb reduced its promoter activity.
2) Promoter Activity of the HHV-6 MIE Region when Stimulated by a Cell with TPA ( FIGS. 3 and 4 )
Vero cells were stimulated with 12-O-tetradecanoyl phorbol 13-acetate (TPA) to measure the promoter activity of HHV-6 MIE, and all promoter activities were increased, and showed substantially the same level as that of HCMV MIE promoter ( FIG. 3 ).
However, in L929 cells, no increase in promoter activity was observed upon cell activation with TPA stimulation ( FIG. 4 ). This is believed to be due to the difference in reactivity of TPA on cell type.
In Vero cells, it is believed that TPA increased the HHV-6 MIE promoter activity by inducing a large amount of a variety of transcriptional activation factors. That is, the maximum activity of HHV-6 MIE promoter is as much as HCMV MIE promoter. Therefore, the promoter of the present invention has been demonstrated with respect to its specificity and selectivity.
As such, in the present invention, adhesive cells such as Vero cells, HEL cells, L929 cells, 293 cells, U373 cells, CMV promoters showed ten times more potent activity than that of HHV-6 ( FIG. 1 ). However, in cells derived from human lymphocytes such as THP-1 cells, SupT1 cells, U938 cells, several times as much activity as that of CMV promoter was observed in HHV-6 promoter, and it was also observed that the more truncated, the more potent activity was found.
Promising promoters from HHV-6 have been confirmed, and from these results, it is understood that these promoters can be applied to DNA vaccines (mumps vaccines) and are extremely promising. HCMV IE promoter was used as a control to compare and study the HHV-6B MIE promoter activity which has been cloned by the present inventors, in a luciferase expression system. As a result, in adhesive cells such as 293 cells, Vero cells and the like, HHV-6MIE promoter only showed about one tenth as much activity as that of HCMHE promoter. However, in lymphocyte cells such as SupT1, and U937 and the like, it was found that several times greater expression efficiency was obtained. Conducting an assay on the expression of the outer membrane glycoprotein of JEV by using p9u/JEVenv linked to JEV cDNA downstream of the subject promoter, no expression of the JEV protein was detected in any adhesive cells or flowing lymphocytes after 48 hours of transfection.
On the other hand, in pcDNA3.1/JEVenv using the IE promoter of HCMV, the expression of JEV protein was confirmed.
Moreover, in JEV infected Vero cells, which were used as a positive control, outer membrane glycoprotein was readily detected. In order to analyze the cause, transfection efficiency was confirmed using GFP protein expression plasmids. As a result, the introduction efficiency in SupT1 cell was as low as 0.1% or less, however, adhesive 293 cells and Vero cells had a higher introduction efficiency of 45% and 20%, respectively. HHV-6 MIE promoter cloned, showed a several times higher expression activity than HCMV MIE promoter in lymphocyte cells. However, expressed gene was not detected with its activity when it was converted to outer membrane glycoprotein of JEV.
It is of interest that the HHV-6 MIE promoter cloned herein showed several times higher expression activity than that of the HCMV-IE promoter in lymphocytes. However, it was unpredictable that when the gene to be expressed had been converted to outer membrane glycoprotein of JEV from the reporter gene, no activity was detected. Therefore, the cause thereof was analyzed as to whether expressed JEV protein acted in a feedback manner, and thus the promoter activity was inhibited in an adverse manner, or that alternatively the expressed antigen is unstable in these cells.
The present Example is summarized as follows:
1) HHV-6 MIE promoter showed about ten times higher activity than HCMV MIE promoter in lymphocyte cells, in particular, monocyte/macrophage cells.
2) In epithelial adhesive cells, HHV6 MIE promoter activity was about one tenth of that of HCMV MIE promoter.
3) HHV-6 MIE promoter is suggested to exhibit substantially the same activity as HCMV MIE promoter under conditions where a large amount of a variety of transcriptional factors was induced.
As described above, in the present Example, those which were inserted about 12 kbp (6MIEP) upstream of the major immediate early (MIE) gene of HHV-6B and about 700 bp upstream of U95 gene (6U95) upstream of the luciferase gene of pGL3Basic vector (Promega) were used. In comparison to the conventional promoters, in order to study the possibility of the application of these IE promoters to DNA vaccines, comparison with human cytomegalovirus (HCMV) IE enhancer-promoter (CMVP) in activity were conducted using blood cell lineage cells. In the present Example, immediate early (IE) promoter encoded by human herpes virus 6B (HHV-6B) was demonstrated to have extremely high activity in blood cell lineage cells.
4) Furthermore, as depicted in FIG. 7 , it was shown that activities in the respective fragments were investigated, and at least −572 to −427 and in particular −1051 to −427 upstream of the initiation point have promoter activity with preferable enhancer activity. The site of −417 to +1 appears to be necessary for promoter activity, and the enhancer activity appears to be necessary to secure specificity. The portions responsible for enhancer activity are elucidated to have NF-κB and AP-1 motifs. Therefore, it appears that it is important to have these motifs in order to have specificity in lymphocytes.
Example 2
MIE and U95 Promoters of HHV-7
Next, experiments relating to promoters from HHV-7 were conducted.
The activity of two immediate early promoters of HHV-7 (7MIEP, 7U95P) were compared with the activity of cytomegalovirus (CMV) promoter and HHV-6 IE promoter (9U and U95). Methods of comparison are as follows: the respective promoter regions were inserted upstream of the luciferase gene of pGL3-Basic Vector (Promega), which were transfected with the respective cells to compare the activity thereof using luciferase activity as reference. In order to study the effects of the R2 region present upstream of the respective promoters, a variety of deletion variants have been prepared to measure promoter activity.
(Outline)
As a reporter plasmid, about 500 bp from the respective MIE and u95 genes of HHV-7 (7MIEP and 7U95P) were inserted upstream of luciferase gene of pGL3Basic vector (Promega) and used in the present Example.
A reporter plasmid was introduced to T cell lines (Jurkat, Molt-3, SupT-1), and bone marrow cell line (SAS-413) with lipofection methods, and to peripheral blood monocytic cells (PBMC) with electroporation, and luciferase activity was measured. As a result, in comparison with HCMV MIE promoter, HHV-7 MIE promoter and HHV-7 U95 promoter showed several times higher activity than HCMV MIE promoter in T cell lines, and in SAS-413 cells, HCMV MIE promoter has more than ten times higher activity. In the experiment where introduction was made to three lots of PBMC, HHV-7 MIE promoter and HHV-7 U95 promoter showed low activity. In comparison with HHV-6 IE promoters (9U and U95), both promoters of HHV-7 showed lower activity in any cell species. Further, in the experiments with the deletion mutants of the respective HHV7 MIE promoter and HHV7 U95 promoter, it was shown that although there is some difference from cell type to cell type, R2 is responsible for major enhancer activity against both promoter's activity. In the present Example, it was demonstrated that immediate early (IE) promoter encoded by human herpes virus 7 (HHV-7) has extremely high activity in blood cell lineage cells.
Hereinafter, materials and methods are described in detail.
(Materials and Methods)
1) Cells—The Following Five Types of Cells were Used for Measuring Promoter Activity.
(1) Jurkat cell (derived from human T cell)
(2) Molt-3 cell (derived from human T cell)
(3) SupT1 cell (derived from human T cell)
(4) SAS-413 cell (derived from human bone marrow cell)
(5) peripheral blood monocytic cells (PBMC)
2) Plasmids for Measuring Promoter Activity
pGL3 Basic (Promega) having Firefly luciferase gene was used for measuring promoter activity.
3) Promoter Sequences Inserted into pGL3 Basic HHV-7 MIE gene promoter region (7MIEP) and HHV-7 U95 gene promoter region (U95P) were amplified to about 500 bp by PCR, and deletion mutants were prepared for each. These are schematically illustrated in FIG. 8 .
(1) 7MIEP (−493) [one inserted with upstream 493 pb to downstream 22 bp from the transcription initiation point of HHV-7 MIE gene] (SEQ ID NO: 26)
(2) 7MIEP (−388) [one inserted with upstream 388 pb to downstream 22 bp from the transcription initiation point of HHV-7 MIE gene] (SEQ ID NO: 27)
(3) 7MIEP (−233) [one inserted with upstream 233 pb to downstream 22 bp from the transcription initiation point of HHV-7 MIE gene] (SEQ ID NO: 28)
(4) 7U95P (−484) [one inserted with upstream 484 pb to downstream 16 bp from the transcription initiation point of HHV-7 U95 gene] (SEQ ID NO: 29)
(5) 7U95P (−379) [one inserted with upstream 379 pb to downstream 16 bp from the transcription initiation point of HHV-7 U95 gene] (SEQ ID NO: 30)
(6) 7U95P (−304) [one inserted with upstream 304 pb to downstream 16 bp from the transcription initiation point of HHV-7 U95 gene] (SEQ ID NO: 31)
pGL3 Basic without promoter sequence has been used as a control.
4) Transfection of Cell with Plasmids
Transfection was conducted regarding Jurkat cell, Molt-3 cell, SupT1 cell, and SAS-413 cell with lipofection using Lipofectamine 2000 (Invitrogen), and regarding PBMC, using electroporation with Nucleofector (amaxa).
In order to correct transfection efficiency, expression plasmids of Renilla luciferase (pRL-TK, Promega) were simultaneously introduced to a cell, and Renilla luciferase activity was measured. pRL-TK expresses Renilla luciferase under control of herpes simplex virus thymidine kinase (TK) promoter.
pGL3 reporter (1.2 μg) and pRL-TK (50 ng) were mixed together and 2 μl of Lipofectamine 2000 were added thereto to conduct transfection.
5) Measurement of Luciferase
For the measurement of luciferase activity, Dual-Luciferase Reporter Assay System (Promega) was used.
The cells were collected 16 hours after the transfection, and were lysed in cell lysis solution (100 μl). To Five μl of supernatant of cell lysis solution, firefly luciferase substrate solution (25 μl) was added, and immediately thereafter, luminescence was measured using a luminometer. Next, to the sample after the measurement, Renilla luciferase substrate solution (25 μl) was added and immediately thereafter, luminescence was measured using a luminometer.
(Results)
1) Activity of Promoter Region of HHV-7 MIE
As a result of experiments using four types of cell lines, when compared with the activity of CMV promoter, 7MIEP (−493) showed about 6-7 times higher activity in Molt-3 cell and SuptT1 cell, similar activity in Jurkat cells, and about 1/11 activity in SAS-413 cells. Moreover, when comparing with HHV-6 IE promoters (9U and U95), in all cell types, 7MIEP (−493) showed lower activity ( FIG. 9 ).
As a result of experiments using three lots of PBMC, the activity of 7MIEP (−493) was similar or slightly lower than CMV promoter and 9U, and similar or slightly higher than HHV-6 U95 ( FIG. 10 ).
2) Activity of HHV-7 U95 Promoter Region
As a result of experiments using four types of cell lines, when compared with the activity of CMV promoter, 7U95P (−484) showed about 2.5 times higher activity in Jurkat cells, four time in Molt-3 cells, twenty times in SupT cells, however, about ⅛ activity in SAS-413 cells. Moreover, when comparing with HHV-6 IE promoters (9U and U95), U95P (−484) showed slightly higher activity in SupT1 than U95, however, was about ½ of that of 9U, and showed lower activity in other cells ( FIG. 9 ).
In an experiment where three lots of PBMC were used, 7U95P (−494) showed only about ½ to ¼ as much promoter activity as that of the others. ( FIG. 10 ).
3) Effects of the R2 Region on Promoter Activity
It was elucidated as a result of an experiment where the respective deletion mutants of 7MIEP and 7U95P were introduced into four types of cell lines, that it depends on the type of cell whether the promoter activity is lowered by the deletion of R2. Specifically, 7MIEP showed no effects with the R2 deletion in Jurkat cells, but reduced its activity by about ⅕ to ½ in other cell lines. Moreover, 7U95P showed no effects by R2 deletion in SAS-413 cells, but reduced its activity by about 1/7 to ½ in other cell lines. ( FIG. 11 ).
(Summary)
The present Examples are summarized as follows:
1) 7MIEP (−493) and 7U95P (−494) both generally showed more potent activity than CMV promoter in T cell lines, but showed lower activity in the SAS-413 cell, which is a bone marrow cell line. In PBMC, 7MIEPO (−493) showed substantially the same activity as CMV promoter, and 7U95P (−494) showed lower activity than CMV promoter.
2) In comparison with HHV-6 IE promoters, all cell types showed higher activity in two types of IE promoters of HHV-6 (9U and U95) than 7MIEP (−493) and 7U95 (−494).
3) It was shown that the R2 region functions as an enhancer against 7MIEP and 7U95P in a number of cells. Transcriptional factors binding to the R2 region are unidentified, but in view of the fact that the R3 region of HHV-6 functions as an enhancer of the U95 promoter by binding NF-κB, it is highly likely that the NF-κB binding motifs present in a repetitive manner in the R2 region may be responsible for enhancer activity of the R2 region ( FIG. 8 ).
Example 3
Construction of Specific Deletion System
Knocking out of gene expression in blood cell lineage cells is conducted using an IE promoter and the RNAi method. IE promoters are advantageous for analysis since they are expressed in blood cell lineage cells in a large amount.
1) Preparation of Cells (in the Case of Macrophages)
Healthy human peripheral blood is obtained and separated and purified by density gradient using Ficoll/Hypaque. The PBMCs are cultured in a AIM V serum medium (Life Technologies) supplemented with M-CSF (R&D systems, 100 U/ml). The medium is exchanged every three days, and macrophages at Day 6 or 7 are used for experiments.
2) Preparation of siRNA Expression Retrovirus Vector
In order to express hair-pin type RNA, a synthetic oligo-DNA comprising “a sense strand target sequence”, “a loop sequence”, “an antisense strand target sequence” and “a terminator sequence” is prepared. Such a sense strand target sequence, loop sequence, antisense target sequence, terminator sequence may be made using well known technology in the art. Those skilled in the art can readily understand that when actually using these, an appropriate sequence may be employed depending on the actual situation.
The above-mentioned DNA is incorporated into a plasmid vector in which the oligo-DNA is linked downstream of the IE sequence, and of gag, pol and env which are necessary for replication of a retrovirus, and which comprises Neo R gene making use of restriction enzyme sequences and the like. Plasmid vector produced (10 μl) is added to 100 μl of competent cells and transformation is conducted and cultured for 16 hours at 37 degrees Celsius after plating into LBAmp plate. Colonies obtained by the transformation are cultured on LBApm liquid medium at 37 degrees Celsius for 16 hours, and plasmids are extracted and purified using conventional methods from the culture solution.
Retrovirus packaging cells expressing gag, pol and env are plated on a disc with a 10 cm diameter, and transfection reagent is opened to transfect the plasmid (10 μg). 24-48 hours later, the cells are subjected to limitation dilution into G418 containing medium (500 μg/ml) and passaged.
Every three to four days, G418 medium is exchanged and cultured for about two weeks in total. Colonies are collected and at the time where growth is found at a confluent level on a six-well plate, the medium is changed to a G418 free medium and the supernatant is collected 24 hours later. The cells will be stocked.
Retrovirus vectors included in the supernatant are subjected to limitation dilution, and infected into NIH/3T3 cells, and colonies grown are counted to calculate the infection value.
3) Gene Introduction Experiments Using Retrovirus Vectors
Retrovirus vectors are infected with blood cell lineage cells such as macrophages prepared in 1). Immediately after washing, it was plated to form 0.5-2.5×10 4 cells/cm 2 on a plate. Twenty four hours after the infection, the medium is exchanged with G418 containing medium, and every three to four days, medium is exchanged. About two weeks later, gene introduced cells are obtained. The cells are used to confirm the expression level of the desired knocked out gene.
These experiments are conducted to actually confirm that after gene introduction, lymphocyte specific expression of a foreign gene can be knocked out with the promoter of the present invention.
Example 4
Specific Expression
Instead of the RNAi of Example 3, a nucleic acid molecule encoding a gene (for example, cytokines such as TGF β) desired for expression is introduced.
As a result, by conducting similar experiments as in Example 3, after gene introduction, it is confirmed that the promoter according to the present invention actually induces the lymphocyte specific foreign gene expression.
As described above, the present invention is illustrated by way of the preferred embodiments. However, it will be understood that the scope of the present invention should be interpreted only by the accompanying claims. It will also be understood that the patents, patent applications and literature cited herein should be incorporated by reference as if set forth fully herein. Various other modifications will be apparent to and can be readily made by those skilled in the art without departing from the scope and spirit of this invention. Accordingly, it is not intended that the scope of the claims appended hereto be limited to the description as set forth herein, but rather that the claims be broadly construed.
INDUSTRIAL APPLICABILITY
The present invention provides promoters which selectively induce the expression of protein in an immune responsible cells such as T lymphocytes. The promoters of the present invention are useful in method and medicaments for effectively preventing or treating immune diseases such as acquired immunodeficiency syndromes and the like. The present invention is also useful in the technologies for efficiently conducting gene therapy. | It is intended to provide a promoter for inducing expression selectively and strongly in an immunocompetent cell and/or a blood cell such as a lymphocyte. In the invention, the object was achieved by finding that HHV6 MIE promoter, HHV7 MIE promoter and HHV7 U95 promoter unexpectedly induce a specific expression in an immunocompetent cell and/or a blood cell such as a T lymphocyte. By utilizing the promoters, a selective delivery of a DNA vaccine or the like can be realized. | 2 |
BACKGROUND OF THE INVENTION
The present invention relates to a hydraulic turbine which is constructed primarily of plastic and uses water to lubricate the bearing joints and gear meshings.
The three types of hydraulic turbines presently used to produce electricity are the Pelton wheel, the Kaplan turbine and the Francis turbine. They are all made of steel and require special bearings and transmissions, which must be lubricated with oil and must not come in contact with water. The steel components may suffer damage from corrosion and cavitation. Water-proofing of the bearings and transmission is costly and oil lubrication may require maintenance.
Hydraulic turbines used for small scale hydroelectric generators, known as micro-hydroelectric plants, are generally expensive and not very well suited to their application. The prior art turbines are heavy, expensive to construct and require maintenance. It is desirable with micro-hydroelectric plants to have a turbine generator which is light in weight for easier installation, low in cost since the user is usually an individual and not a utility company, and virtually maintenance free to reduce the trouble involved with maintenance and possible breakdown.
SUMMARY OF THE INVENTION
The present invention provides a light weight, durable, maintenance free and inexpensive hydraulic turbine. The turbine is made using a light weight plastic construction which can be inexpensively molded to create a turbine which is resistant to corrosion and cavitation. The problems of lubrication and water-proofing are substantially reduced by using bearings constructed of water-lubricated plastic which utilize the surrounding water for lubrication and do not require watertight sealing. Thus the turbine according to the present invention offers numerous advantages over the turbines of the prior art.
Some of the advantages of the invention are that water-proofing is greatly reduced so that maintenance is reduced, the bearings and gears are water lubricated by water flowing through the turbine so that oil is not required and therefore lubrication needs no maintenance, the turbine may be constructed by using gravity castable plastic which eliminates any costs of machining, the turbine works well on the 5 to 30 kW scale of generator output, the plastic construction is resistant to the damages of cavitation, corrosion, and wear due to possible particles in the hydraulic flow, and the gears of the transmission having water lubricated plastic teeth provide a soft transmission and create little noise. The turbine according to the invention is of the Kaplan type with distributors placed upstream.
More specifically, the present invention provides a hydraulic turbine comprising a rotor having a hub with a longitudinal axis and turbine blades extending radially from the hub, a gear solid with the rotor, drive means including at least one gear meshed with said gear solid with said rotor to give drive to or obtain drive from the rotor, a surrounding housing containing the rotor, and mounting means for rotatably mounting the rotor in the housing to secure the rotor against longitudinal and radial forces during operation. The turbine is improved according to the invention in that the gear of the drive means meshed with the rotor gear has teeth made of a water lubricated plastic material having a low coefficient of friction, the gear connected to the rotor also has teeth made of the same plastic material, the rotor is made of the same plastic material, the mounting means includes bearing means made of the plastic material, the bearing means being coaxial with the longitudinal axis, and the gear or gears of the drive means, the gear connected to the rotor and the bearing means being all contained within the housing and lubricated, in operation, by water passing through the housing.
The transmission to an electric generator is advantageously achieved in a preferred embodiment of the invention by providing a rim connected around the blades, which gives the rotor an advantageously larger rotational inertia, the rim being provided with a gear defining surface which forms said gear solid with the rotor and meshes with the gear of the drive means to the generator. The gear ratio between the rim surface and the drive means gear is suitable to drive the generator at an appropriate rotational speed, thus the transmission is simplified. The assembly of the turbine as a whole is simplified by constructing the housing in two plastic parts, into which the rotor, mounting means, and gears are placed. The number of components of the turbine can be reduced to less than six.
Other objects and features of the present invention will be made clear by means of the following description of a preferred embodiment of the invention taken in connection with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a partly cut away perspective view of the turbine and generator according to a preferred embodiment of the invention.
FIG. 2 is a cross-section of the turbine according to the present invention taken in a vertical plane through the axis A.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
The hydraulic turbine 1 according to the invention as shown in FIG. 1 comprises a rotor 3 from which blades 11 extend radially, a housing 7 and a generator 5.
As better shown in FIG. 2, the rotor 3 is provided with a center hub 9 and an annular rim 13 connecting the blades 11. The rotor rotates on a shaft 23 which is connected at each end to bearings 21 which seat into mounting means 19. The mounting means 19 comprises a nose cone and a tail cone.
Construction and assembly of the hydraulic turbine 1 is simplified by forming the turbine housing 7 in two halves which are joined together by 0-ring 27 and bolts 43. The mounting means 19 are attached to each respective half of the housing 7 by struts 25.
The turbine 1 comprises for the most part only four major pieces, namely the two halves of the housing 7, the rotor provided with shaft 23 and bearings 21, and gear 17 provided with a shaft 24 and bearings 41. As a result, assembly of the turbine 1 is not complicated and requires little time.
In the preferred embodiment of the invention, the turbine 1 is used to drive a generator 5. The annular rim 13 is provided with a ring gear surface 15 which meshes with gear 17 contained on the drive shaft 24. The drive shaft 24 is provided with bearings 41 and a watertight seal 39 to rotatably connect the gear 17 to the generator 5.
In the preferred embodiment all components are made of a plastic material which is capable of being water lubricated except for the shafts 23, 24, the 0-ring seal 27 and the bolts 43. The shafts 23, 24 are preferably made of stainless steel. The water lubricated plastic is polyurethane.
The water lubrication requires that water be free to circulate about the bearing joints 21 and 41 and at the meshing between the gear 17 and the gear surface 15. The water circulating about the joints should be free of abrasive particles, such as sand. In the preferred embodiment shown, the hydraulic turbine 1 may be connected to a flow of water derived from a stream for microhydroelectric purposes. In this case, there will be fine particles such as sand in the flow of water in the housing 7. Therefore the surface of the rotor 3 where the rotor 3 meets the surface of the housing 7 and the mounting means 19 is firstly made flush, so that a minimum of turbulence is created by the joint, and secondly, a tongue and groove arrangement is provided to restrict the flow of water and thereby also the flow of water with abrasive particles into the chamber surrounding the gear 17 and the chamber surrounding the bearings 21. More specifically the surface 29 of the rotor 3 is made flush with the interior surface of the housing 7 and the rim 13 is provided with annular grooves 31 which receive annular flanges 33 of the housing. At the interface between the rotor 3 and the mounting means 19, there is provided only a single tongue and groove arrangement, comprising a surface ridge 35 projecting into a groove next to an annular flange 37. Similarly, the interface between the surface of the rotor at the ridge 35 is flush with the surface of the mounting means 19 so that turbulence at the interface is minimized.
As can now be understood, the turbine design according to the present invention is based on using plastic in most every part of the turbine 1. The turbine 1 is of the Kaplan type and the upstream struts 25 also act in the preferred embodiment as distributors. The torque is transmitted to the generator 5 by pair of gears 15, 17 of the necessary ratio. The gear 15 is situated at the circumference of the blades 11 of the rotor 3 and the other gear 17 on the shaft 24 of the generator 5. Both gears 15,17 are held in place by two parallel stainless steel shafts 23,24 that turn in self-lubricated plastic bearings 21,41 immersed in water. Also for lubrication, the gears 15,17 are immersed in water. A non-watertight mechanical joint assures that the pressure of the water is all used by the blades 11 of the propeller rotor 3. The water going through the mechanical joint will then lubricate the gears 15,17. All the major parts of the turbine except the two stainless steel shafts 23,24 are made of plastic.
The advantages of the structure are as follows. Watertightness is not required which assures water lubrication of every part in friction contact, such as the teeth of the plastic gears 15,17 and bearings 21,41. The gear 15 provided on rim 13 is deliberately oversized to provide sufficient inertia for easy speed control. The use of plastic provides a very light weight machine which simplifies the installation of the turbine 1. Low cost of the turbine 1 is realized by the ease of molding gravity castable plastic which avoids expensive machining. The turbine 1 is built for low output (5 kW to 30 kW) but of course the design can be adapted for larger power output (≧100 kW). A simple construction is achieved by modular assembly of all the parts which further makes the installation and transportation easier. Only six major parts and four bearings form the turbine 1. No specialized labor is required for the assembly. Plastic will not corrode like steel, and the turbine 1 requires low maintenance.
The advantages of using a water lubricated plastic, whose characteristics permit a low cost and rapid production, and a long life for all the parts of the turbine 1, are as follows. The type of plastic used in the turbine is a gravity castable type. To produce large parts used in turbines at a low cost, it is necessary to use a gravity castable type of plastic, since the molding pressure of nongravity castable plastic can reach 12000 psi, and therefore the force needed to keep two faces of a mold together is very great. Such great forces complicate, if not render impossible, the construction of the mold. The disadvantages of non-gravity castable plastic for large turbine components can result in a higher production cost.
Kaplan turbines are prone to problems of cavitation. The cavitation is often the result of operating outside design parameters. Cavitation refers to the small implosions which are created on the blades 11 at points where the hydraulic pressure fluctuates from very low to very high in a very short time frame. The cavitation implosions can be compared to shocks. Therefore, the plastic used in the turbine 1 has to resist high shocks, which is achieved by the elasticity of the plastic material. However, the plastic used must be rigid enough not to twist or bend under the loads created by the water pressure on the blades 11 and the struts 25. The plastic used is corrosion free to avoid degradation of the plastic due to long exposure to water, resists the friction created by sand contained in the water, and is capable of being water lubricated for the parts in friction contact such as the teeth of the gears 15,17. Two examples of gravity castable plastic are urethane and epoxy.
The turbine 1 according to the invention relies upon non-watertight mechanical joints to allow water passing through the turbine 1 to lubricate the gears 15,17 and the bearings 21,41. The mechanical joint must limit the flow of water such that the gears 15,17 and bearings 21,41 are sufficiently lubricated and all the water pressure is used by the rotor blades 11. The tongue and grooves 29,33,31 and 35,37 of the rim 13 and the hub 9 respectively, are not in contact to avoid friction which can reduce torque considerably.
The use of plastic for the construction of both water lubricated gears 15,17 permits a soft transmission of torque with a low noise level. Moreover the construction allows a looseness of both gears' 15,17 tooth profile and center line distance without negative results on the life of the gear teeth or on the smoothness of the torque to be transmitted.
In the above description, although reference has been made to the use of water in the turbine, it is to be understood that any hydraulic fluid, which can lubricate the plastic gear teeth and bearings, may be used instead of water.
Although the description of the present invention has been made by reference to the preferred embodiment, it is to be understood that the above description is not to be limitive of the scope of the present invention as defined in the following claims. | There is disclosed a hydraulic turbine which is constructed primarily of plastic and uses water to lubricate the bearing joints and gear meshings. The invention provides a turbine which is light in weight for easier installation, low in cost and virtually maintenance free reducing the trouble involved with maintenance and possible breakdown. The invention is well suited to drive an electric turbine for micro-hydroelectric applications. | 5 |
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application is a divisional of application Ser. No. 09/621,509, filed Jul. 21, 2000, pending.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates generally to environmental control of storage buildings and facilities. More particularly, the present invention relates to the control of such parameters as temperature, humidity, and carbon dioxide (CO 2 ) within a storage facility wherein produce or like commodities are stored.
[0004] 2. State of the Art
[0005] Produce providers often desire to store fruits and vegetables for extended periods of time. Produce is often stored to maintain adequate supplies during periods when a particular commodity is out of season. Processors of fruit and vegetables increasingly desire commercial growers to store their products for longer and longer periods of time. Indeed, processors require a year-round supply of produce while requiring that the quality of such produce remain high.
[0006] To store produce for extended periods of time without substantial degradation of quality, it becomes imperative to control the environment in which the produce is stored. Control of the storage facility environment may include the control of, for example, temperature, humidity, and air quality including carbon dioxide (CO 2 ) content. Typically, control of such parameters in a storage facility environment entails movement of air within the facility. Oftentimes, this includes introduction of air from outside the facility. Other times it may simply involve the circulation of existing air inside the storage facility.
[0007] One method of controlling the environment has been to place fans or air-handling units in the facility. The fans may be turned on when the temperature rises above a predetermined upper level and shut off when the temperature of the facility reaches a predetermined lower level. A system of this type is described in U.S. Pat. No. 3,801,888 to Faulkner. This type of system utilizes the fans at full power, allowing them to cool the facility at a relatively quick pace, but also allowing temperatures or other environmental parameters to change rapidly within a specified range. Rapid changes in temperature or temperature spikes may often cause a temperature-induced shock to the stored inventory, ultimately resulting in quality degradation. Similarly, rapid changes in other environmental parameters may degrade the quality of the stored commodity.
[0008] Some systems have sought to utilize multi-speed fans such as is described in U.S. Pat. No. 3,896,359 to Olander et al. Such a system is implemented with the desire of allowing temperature or other environmental changes to take place at a slower rate. However, even these systems do not allow the desired flexibility in controlling a chosen environmental parameter within the storage facility. Such systems employ low- and high-speed control of the fan or air-handling unit. While this allows for a stepped transition from one temperature to another, it simply reduces the magnitude of any temperature spike rather than providing a continuous control of temperature within the storage facility. This is because the high- and low-speed settings each correspond to a defined range of operability. Thus, for example, in controlling temperature, the fans will remain inoperative if the temperature of the facility is within a defined temperature range. The fans will then operate at a low-speed setting once the temperature increases into a second defined range. Finally, the fans will operate at a high-speed setting if the temperature increases into a third defined range. The process will reverse itself as the temperature decreases. However, the ranges cannot be defined too tightly, otherwise the fan will be constantly starting and stopping as the temperature fluctuates between the first and second range. On the other hand, the defined ranges may not be set too broadly. If the ranges are too broad, then the temperature will increase to the point where the fans will be operating at the high-speed setting for extended periods of time in an attempt to bring the temperature back to an acceptable value. Also, depending on the commodity being stored, broad parameter ranges may simply not be acceptable from a quality standpoint.
[0009] Another important consideration in the environmental control of a storage facility is the efficient use of power. With most systems relying on fans that are cycled between on and off positions, or those systems having high/low-speed settings, power consumption is of paramount concern to the facility operator. Storing commodities for extended periods of time requires a significant consumption of power with existing systems and methods. The cost of such power, while initially resting with the facility operator, ultimately gets passed along to the consumer in the form of higher prices at the market. Thus, an efficient and accurate environmental control system for storage facilities would be of benefit to more than just the facility operator.
[0010] In view of the shortcomings in the art, it would be advantageous to provide an environmental control system for a storage facility which effectively controls specified environmental parameters while consuming a reduced amount of energy. Such a system or method should be simple to employ in existing as well as new storage facilities.
SUMMARY OF THE INVENTION
[0011] In accordance with one aspect of the invention, a method is provided for controlling the internal environment of a storage facility, such as a storage bin for produce. The method includes the steps of providing a fan, or a plurality of fans, for moving the internal air of the storage facility. The fans are continuously operated within the storage facility. The fans may be operated continuously at a speed which is below their full capacity for continuous parameter control and reduced power consumption. The system monitors a parameter indicative of the internal environment of the storage facility. For example, a temperature sensor may be employed to monitor the internal temperature of the storage facility. Once the temperature has been monitored, the speed of the fans is altered accordingly. If the internal temperature needs to be reduced, then the fans may be operated at a higher rotational speed, increasing the air movement within the storage facility. Likewise, if the air temperature needs to be increased, the fan speeds will again be altered to accomplish this requirement. The same method may be applied in monitoring other parameters and changing the rate of air flow to obtain a desired value for the given parameter.
[0012] Additionally, environmental parameters outside of the storage facility may be monitored to assist in the regulation of airflow inside the storage facility. For example, outside air temperature may be monitored and compared to the desired facility temperature to determine whether outside air should be admitted into the facility via a ventilation inlet. Various restrictions may be placed on the admittance of outside air, such as prohibiting outside air into the facility if the outside temperature is above a specified maximum or below a specified minimum.
[0013] In accordance with another aspect of the present invention, a system is provided for controlling the internal environment of a storage facility. The system includes a fan or multiple fans which are adapted to operate continuously. The fans may be operated continuously at a speed which is below their operational capacity. The fans are placed to move the internal air of the storage facility during operation. Each fan is coupled to a variable speed drive for controlling the operational speed of the fans. At least one sensor is employed to monitor one or more internal environmental parameters of the storage facility such as temperature, humidity, gas levels, or chemical levels. The sensor is coupled to an electronic control unit which is also coupled to the variable speed drive. The sensor provides a signal to the electronic control unit, the signal representing a measured value of an internal environmental parameter. The electronic control unit then provides a signal to the variable speed drive based upon the sensed parameter causing the associated fan to vary in speed accordingly.
[0014] Additional elements may be configured with the system to render greater control and flexibility. For example, sensors monitoring an external environment may be coupled to the electronic control unit to assist in determining fan speed. Ventilation inlets or outlets may also be coupled to the electronic control unit for controlling flow of air into and out of the facility, respectively.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
[0015] The foregoing and other advantages of the invention will become apparent upon reading the following detailed description and upon reference to the drawings in which:
[0016] [0016]FIG. 1 is a plan view of a storage facility in accordance with certain aspects of the present invention;
[0017] [0017]FIG. 2 is an elevational view of the storage facility of FIG. 1 taken along the section line 2 - 2 ;
[0018] [0018]FIG. 3 is a plan view of a storage facility according to another aspect of the present invention;
[0019] [0019]FIG. 4 is a schematic representation of an environmental control system in accordance with certain aspects of the present invention;
[0020] [0020]FIG. 5 is a block diagram illustrative of the logic employed in one embodiment of the invention; and
[0021] [0021]FIG. 6 is a block diagram illustrative of the logic implemented according to another embodiment of the invention.
DETAILED DESCRIPTION OF THE INVENTION
[0022] Referring to FIG. 1, a storage facility 10 implementing an environmental control system according to a particular embodiment of the invention is depicted in plan view. The storage facility includes exterior walls 12 which separate the storage facility from an external environment. A fan 14 , which may be a simple industrial sized fan or any other type of air-handling unit suitable for use in such a facility, is housed at one end of a main air duct 16 or plenum. An interior wall 18 serves as a barrier between the main air duct 16 and a storage area 20 , which is often referred to as the storage bin. A series of secondary or lateral air ducts 22 pass through the interior wall 18 from the main air duct 16 to the storage bin 20 . Each lateral air duct 22 includes a plurality of vents or openings 24 which allow for distribution of air throughout the storage bin 20 .
[0023] A ventilation inlet 26 is located in an exterior wall 12 near the fan 14 . The ventilation inlet 26 allows for external air to be introduced into the main air duct 16 when desirable. An outside sensor 28 is located external to the facility 10 to monitor a defined environmental parameter. For example, the temperature or humidity of the external air may be monitored to determine the suitability of external air and the desirability of admitting such air. It is contemplated that one or more sensor(s) may be used in such a facility to monitor various external environmental parameters.
[0024] Generally, airflow is induced by the fan 14 and travels down the main air duct 16 as indicated by directional arrows 30 . Airflow then continues into the lateral air ducts 22 as indicated by directional arrows 32 and into the storage bin 20 through the ventilation openings 24 of the lateral air ducts 22 . The air may then be exhausted through ventilation outlets or returned to the main air duct 16 as more fully described below. The airflow provided by the fan 14 is used to control the internal environment of the storage bin 20 . The circulation of air, including the introduction of external air and exhausting of internal air when necessary, can be controlled to manipulate various internal environmental parameters. Such parameters may include, for example, temperature, humidity or CO 2 content of the facility.
[0025] Referring now to FIG. 2, an elevational view of the facility 10 is depicted as indicated by sectional line 2 - 2 of FIG. 1. The ventilation inlet 26 is shown to be adjusted by an actuator 34 . The ventilation inlet 26 is shown to be a hinged door or hatch actuated by a hydraulic or pneumatic cylinder. While this illustrated embodiment is simple and effective for the purpose of introducing external air into the storage facility, it is to be understood that any method of creating and actuating a ventilation inlet known in the art is considered to be within the scope of the disclosed invention.
[0026] A ventilation opening 36 is formed within the interior wall 18 . Through the ventilation opening 36 , the upper limit of a produce pile 38 may be seen. While not shown in FIG. 1, the produce pile is located in the storage bin 20 and covers the lateral air ducts 22 . In addition to allowing one to view the inside of the storage bin 20 , the ventilation opening 36 also allows air to return from the storage bin 20 and back into the main air duct 16 . Thus, when the ventilation inlet 26 is closed, air is circulated through the main air duct 16 as indicated at 30 , through the lateral air ducts 22 as indicated at 32 , up through the produce pile 38 , and through the ventilation opening 36 back to the main air duct 16 as indicated by directional arrows 40 .
[0027] When the ventilation inlet 26 is opened, external air is allowed into the main air duct 16 as indicated by directional arrow 42 . In such a scenario, the external air combines with the recirculated air to create a mixed flow. During mixed flow operation, it may be necessary to exhaust some of the air due to a positive pressure experienced in the storage bin 20 . While not shown in either FIG. 1 or 2 , an exhaust vent may be placed in an exterior wall 12 or in the ceiling of the storage bin 20 to accommodate such exhaust. While various types of vents may be utilized, an exhaust vent with gravity louvers is often sufficient. This type of vent allows air to exhaust to an external environment when a positive pressure is present on the interior of the building, while prohibiting air flow when the interior of the building experiences a negative or equilibrated pressure. The louvers thus open when an internal positive pressure is experienced and close, due to gravity, in the absence of a positive pressure.
[0028] Additional sensors 44 and 46 are shown in FIG. 2. A supply air sensor 44 is located in the main air duct 16 and allows for the monitoring of a chosen parameter of the supply air prior to its introduction into the storage bin 20 . A return air sensor 46 is located near the ventilation opening 36 to similarly monitor the air as it returns from the storage bin 20 . Thus, the air is monitored at various locations to assist in determining whether any adjustments need to be made. Adjustments would typically include changing the rate at which air is circulated and/or adjusting the amount of external air being introduced into the facility 10 . These adjustments, and the logic of making such adjustments, will be discussed in greater detail below.
[0029] Turning now to FIG. 3, a sectional plan view of the storage bin 20 is shown wherein additional components are shown and described. The produce pile 38 , as described previously, sits atop the lateral air ducts 22 . Air flow is directed through the ventilation openings 24 (as shown in FIG. 1) and through the produce pile as generally indicated by directional arrows 48 . As described above, circulation of the air typically causes the air to return to the main air duct 16 for recirculation. However, in certain circumstances, it may be desirable to create an exchange of air by exhausting air at a more rapid pace. Such a technique would be desirable, for example, to remove air having a higher content of CO 2 than is desired.
[0030] An auxiliary fan 50 is placed at the upper end of the storage bin 20 near an exhaust vent 52 such as a louvered gravity vent. An auxiliary ventilation inlet 54 is located in an exterior wall 12 opposite the fan 50 and exhaust vent 52 . The ventilation inlet 54 is operated by an actuator 56 . When in operation, the auxiliary fan 50 draws external air through the ventilation inlet 54 , across the storage bin 20 , and out through the exhaust vent 52 as indicated by directional arrows 58 . A sensor 60 is located in the storage bin to monitor a desired parameter, such as the CO 2 . It is understood that the actual physical location of the fan 50 and associated vents 52 and 54 , while typically located toward the vertical extremes of the facility, will depend on the actual layout of the storage facility in which they are employed and may be arranged in various configurations to accomplish the same or similar results.
[0031] An auxiliary system, such as that depicted in FIG. 3, assists in maintaining various internal environmental parameters when control of the main system is limited by the external environmental parameters, for example, during an extended period of time the external temperature (as measured by sensor 62 ) may be either too warm or too cold to open the main inlet door 26 for the introduction of fresh air. In such a case, it is still desirable to control the oxygen, carbon dioxide or other gas levels within the storage bin 20 . The auxiliary system shown in FIG. 3 may be utilized to introduce just enough external air to control the gas level without unduly influencing other internal environmental parameters such as temperature or humidity. The auxiliary fan 50 and ventilation inlet 54 may be controlled simultaneously to introduce the proper amount of external air in such a situation.
[0032] Referring now to FIG. 4, a schematic of the environmental control system 100 of the present technique is depicted. A first fan 102 is shown which may be taken to represent the main fan 14 located in the main air duct 16 . A second fan 104 is also shown, and may be taken to represent the auxiliary fan 50 shown in FIG. 3. Each fan 102 and 104 is connected to a variable-speed drive 106 and 108 , respectively. There are numerous types of variable-speed drives commercially available, each having various benefits and features. It is contemplated that the present system and method may be practiced utilizing different types of variable-speed drives for varying the rotational speed of the fans 102 and 104 . For example, a variable-speed drive of the type employing a magnetic clutch would be suitable for use in the present technique. Such a drive varies the current supplied to the clutch causing the magnetic force to vary between the clutch and the shaft. This allows a certain amount of slip to occur between the shaft and the clutch. Ultimately, the rotational speed is varied by varying the amount of slip allowed in the magnetic clutch. While such a drive, and numerous others, may be suitable for use in practicing the present technique, the drives utilized in the presently disclosed embodiment are variable-frequency drives, sometimes referred to as inverter drives.
[0033] As known by those skilled in the art, a variable-frequency drive (VFD) is an electronic controller that adjusts the speed of an electric motor by modulating the power being delivered. More specifically, the speed of the electric motor is controlled by modulating the frequency of the power being supplied. The standard frequency of AC power in the United States is 60 Hz. A standard electric motor constructed for use in the United States is designed to be operated with a 60 Hz power supply. A decrease in the frequency of the power supply will result in a corresponding decrease in motor speed. For example, an electric motor that rotates at 100 rpm with a 60 Hz power supply would run at 50 rpm when the power supply is reduced to 30 Hz.
[0034] Referring still to FIG. 4, a set of actuators 110 and 112 represent the actuators 34 and 56 depicted in FIGS. 2 and 3, respectively. A plurality of sensors 114 , 116 , 118 and 120 are also shown and represent the various sensors disclosed and discussed above. Each of the VFD's 102 and 104 , the actuators 110 and 112 , and the sensors 114 , 116 , 118 and 120 are connected to a control unit 122 by way of electrical wiring 124 such as a dedicated harness. Alternatively, the electrical wiring could be a common bus such as in a controller area network. The control unit 122 receives signals from the various sensors 114 , 116 , 118 , and 120 , processes the information it receives, and then sends out command signals to the VFD's 106 and 108 and the actuators 110 and 112 . The VFD's 106 and 108 then interpret the command signals and send corresponding drive signals to the fans 102 and 104 , respectively. In the above described embodiment, a drive signal includes a signal from a power supply having an appropriately modulated frequency.
[0035] Through proper programing of either the control unit 122 , the VFD's 106 and 108 , or both, maximum speed settings may be established for the fans 102 and 104 . Likewise, minimum speed settings may be set. Furthermore, parameter setpoints may be established for the overall operation and logic of the system. For example, a temperature value at which the storage bin is to be maintained may be defined. Having a defined temperature value and sensing air temperature at various points in the stream of air flow, the system will operate to adjust fan speed and/or adjust the mix of air flow to alter an existing environmental parameter. The logic of controlling the environment with such a system will be discussed in greater detail below.
[0036] It is noted that with such a system, greater flexibility is realized through the use of variable-speed drives. By using VFD's or some other variable-speed drive, more gradual changes to the environment may be achieved. The possibility of reduced power consumption is also seen in the practice of the present technique. This is because the relationship between power consumption and fan speed is nonlinear. For example, it has been established that in a system similar to that described herein, a twenty percent reduction in fan speed results in a fifty percent reduction in power consumption. Knowing that the rate of air flow varies linearly with fan speed, a simple calculation may be performed to compare air flow and power consumption for a system operating at full speed with a system operating at a reduced fan speed of eighty percent. A system operating at full power may circulate air, for example, at 100,000 cfm (cubic feet per minute). This system will circulate 6,000,000 cubic feet of air in a given hour. The reduced-speed system, however, will circulate air at a rate of 80,000 cfm requiring an hour and fifteen minutes to circulate 6,000,000 cubic feet of air. However, even with the additional fifteen minutes of operating time, the reduced-speed system only consumes sixty-two and a half percent as much power as the full-speed system. Indeed, operating the fan at even slower speeds nets even larger savings in power.
[0037] With reduced-fan speed consuming considerably less energy than does full-speed operation, a fan can be operated continuously to maintain the storage facility environment within a tightly defined parameter range. For example, if the storage facility is desired to be maintained at a temperature of 50° F., the fans can be operated continuously at a reduced speed to maintain the temperature within a few degrees. Furthermore, with proper fan speed control, in conjunction with proper inlet ventilation control, temperature can be maintained within a range of approximately 1° F. Thus, large temperature spikes may be eliminated from the storage environment with reduced power consumption.
[0038] It is noted that while the schematic of FIG. 4 shows a single control unit 122 , it is possible that multiple controllers be employed in operation of the system 100 . For example, the overall system 100 could be subdivided into subsystems wherein the main fan 102 and drive 106 were considered an individual subsystem. Similarly, the control of the auxiliary fan 104 , drive 108 and auxiliary actuator may be taken together as a subsystem. Indeed, a subsystem may simply include a controlling actuator-associated main ventilation inlet.
[0039] Turning now to FIG. 5, and with reference to FIG. 4, the logic employed according to one aspect of the present technique is discussed. First, a parameter setpoint 142 is defined. The parameter setpoint is the value at which the storage facility environment should be maintained. For example, it may be a value concerning temperature, humidity, CO 2 or some other environmental parameter. For sake of clarity, and not by way of limitation, the use of temperature will be maintained as the specific environmental parameter throughout the following discussion.
[0040] Maximum and minimum fan speeds are defined, as shown at step 144 , and are programed into either the control unit 122 or the VFD 106 (illustrated in FIG. 4). Alternatively, maximum and minimum power consumption rates may be defined for the fans. An environmental parameter is then sensed 146 and an appropriate data signal is communicated to the control unit 122 . The control unit 122 then determines if the sensed temperature is greater than the defined setpoint as indicated at 148 . If the result is affirmative, then the control unit 122 determines whether the current fan speed is less than the defined maximum as shown at step 150 . If this inquiry is affirmative, then the control unit 122 will increase the speed of the fan 102 as indicated at step 152 . Following the increase of fan speed, the temperature is again sensed as shown at step 146 , with the process ready to repeat itself. If the inquiry at step 154 is answered negatively, then the fan speed is maintained at the maximum speed and the process returns to step 146 .
[0041] If, however, the inquiry at 148 yields a negative response, the control unit 122 then will inquire whether the sensed temperature is less than the defined setpoint as shown at 156 . If the result is affirmative, a second inquiry is made as to whether the fan speed is greater than the minimum setting as indicated at step 158 . If the result to this inquiry is affirmative, then the fan speed is reduced as shown at 160 , and the process returns to step 146 . If the inquiry at step 158 yields a negative response, then the fan speed is maintained at the minimum speed as shown at 162 , and the process returns to step 146 . Finally, if the inquiry at step 156 yields a negative result, the process likewise returns to step 146 .
[0042] Thus, using the logic described above, the fan is operated continuously and, if the maximum setting is less than full power, it is operated continuously at a reduced speed. In the example above, the present technique allows for the continuous control of fan speed to maintain the storage facility environment at a defined temperature. It is noted that the chosen parameter need not be temperature. It is also noted that the above logic is in reference solely to fan speed and that the control unit may contemporaneously control the ventilation inlet 26 (shown in FIGS. 1 and 2) to influence the environment as well.
[0043] Turning now to FIG. 6 and referring to FIG. 4, the operational logic regarding the operation of the auxiliary system of FIG. 3 is described. First, parameter setpoints are defined as shown at step 172 . Both an internal setpoint and an external setpoint are defined. The internal setpoint is a parameter value at which the storage facility environment should be maintained. For example, it may be a value concerning temperature, humidity, CO 2 or some other environmental parameter. For sake of clarity, the following example will focus on the control of CO 2 as the internal parameter to be maintained. The external setpoint is a parameter value which is used to override the system in specific instances. For this discussion, the external setpoint is defined in terms of temperature.
[0044] While not shown specifically in FIG. 6, maximum and minimum fan speeds may be defined according to the description in reference to FIG. 5. An internal environmental parameter is then sensed as shown at step 174 , and an appropriate data signal is communicated to the control unit 122 . Again, for this discussion the sensed internal parameter will be the CO 2 level in the storage facility. An external parameter is also sensed as shown at 176 . For this discussion, the external parameter will be the ambient temperature outside the storage facility. The control unit 122 then determines if the sensed CO 2 is less than the defined setpoint as indicated at 178 . If the result is affirmative, then the control unit 122 will decrease the speed of the auxiliary fan 104 as indicated at 180 . Following the decrease in fan speed, the process returns to step 174 . If the inquiry at step 178 is answered negatively, then the control unit 122 determines whether the sensed CO 2 level is greater than the defined level as indicated at 182 . If the result is negative, then the speed is maintained as shown at 184 , and the process returns to step 176 . If, however, the result is affirmative, the control unit 122 further determines if the external temperature is less than the external setpoint as seen at step 186 . If the result to the inquiry at 186 is affirmative, then the fan speed is increased as shown at step 188 and the process returns to step 176 . If the result to the inquiry at 186 is negative, the control unit 122 determines whether the sensed external temperature is greater than the external setpoint as shown at step 190 . Again, if the result to this inquiry is negative, then the fan speed is maintained as shown at step 184 , and the process returns to step 176 . If, however, the result to the inquiry at step 190 is affirmative, then the fan speed is decreased as shown at step 192 and the process returns to step 176 .
[0045] Thus, the inquiries shown at steps 186 and 190 work as a check on the external environment. This allows an override function to be in place such that the admittance of external air by the auxiliary system does not interfere with the maintenance of one or more other environmental values. For example, if the main fan 102 is being utilized to control temperature and the auxiliary fan 104 is being utilized to control CO 2 , the use of external air to sweep out CO 2 may impair the system's ability to control temperature, depending on the temperature of the external air. Thus, the main fan 102 is given priority in the example above, such that control of temperature overrides the control of CO 2 . Of course the main and auxiliary systems could each control parameters different than those attributed in the above example with similar logic employed and similar results achieved.
[0046] It should be understood that while the logic discussed in connection with FIGS. 5 and 6 related to a particular system, the logic may be applied to the other systems or subsystems disclosed herein. For example, the logic of FIG. 5 may be easily adapted for use with the auxiliary system if so desired. Similarly, the logic discussed in connection with FIG. 6 may equally be applied to operation of the main fan or possibly the control of the main ventilation inlet.
[0047] While the invention may be susceptible to various modifications and alternative forms, specific embodiments have been shown by way of example in the drawings and have been described in detail herein. However, it should be understood that the invention is not intended to be limited to the particular forms disclosed. Rather, the invention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the invention as defined by the following appended claims. For example, it is contemplated that while the embodiments and techniques described above have been shown to be combined into a single system, they may operate as individual systems or as subsystems. For example, what has been described as the auxiliary system, i.e., FIG. 3, need not be connected to the same control unit as the systems described in FIGS. 1 and 2. As noted above, multiple controllers may be employed to operate the system in a similar manner.
[0048] It is further contemplated that a single control unit may interact with individual components of the system on an independent basis. For example, FIG. 4 illustrates a system with a single control unit 122 networked with multiple components. Such a control unit 122 may be configured to receive information or data from a first sensor 114 and use that information to control the speed of the first fan 102 . The control unit 122 may then receive a signal from a second sensor 116 for use in controlling the second fan 104 . However, the first fan 102 may be operated at a speed independent of the speed of the second fan 104 . Likewise, contemporaneous and independent control may be exerted over the ventilation inlets.
[0049] Of course, additional components may be introduced into the system for added control and benefit. Such components may include, by way of example, humidifiers, actuated exhaust controls, or fogging equipment for the introduction of desired chemicals into the environment. | A method and system for controlling the environment of storage facilities, including produce and livestock storage facilities, and the like. Movement of air within the facility is accomplished by air-handling units or fans. The speed of each fan is controlled by a variable-speed drive, allowing the fans to run at speeds below full capacity. Environmental parameters, such as temperature or humidity, are monitored to determine the existing state of the environment which is then compared to a desired state. The speed of the fans or air-handling units is adjusted to alter the existing environmental state, bringing it in alignment with the desired state. The fans or air-handling units are operated continuously, typically at reduced capacity. Other various facets are included with the system and method, including the control of the admittance of external air into the storage facility. | 5 |
BACKGROUND OF THE INVENTION
This invention relates generally to absorption cooling systems and to absorption heating and cooling systems and, in particular, to the management of refrigerant for release into the system during part load and shut down conditions.
In an absorption type cooling system, an absorbent is dissolved in a liquid refrigerant to produce a refrigerant-absorbent solution that is suitable for use in the process. When such a system operates under cooling loads that vary, the amount of refrigerant necessary to keep the system running efficiently will also vary. As a result, it is a common practice to equip such a cooling system with a refrigerant adjusting system which includes a refrigerant storage reservoir, and to store refrigerant in or release refrigerant from this reservoir as necessary to keep the concentration of the solution within an acceptable range of concentrations as the cooling load fluctuates. This storage reservoir often takes the form of a sump that is located in or in close association with the system condenser.
One example of a cooling mode refrigerant adjusting system of the above-described type is described in unexamined Japanese application 62-178858, which is assigned to Ebara Ltd. of Tokyo, Japan. In the latter application, there is disclosed an absorption machine in which the gravity flow of liquid refrigerant between the system condenser and the system evaporator is controlled in response to a sensed condition of the system, such as the solution temperature as it is leaving the absorber. A reservoir for liquid refrigerant is provided inside the condenser and the refrigerant is supplied to the evaporator through a first flow path under normal operating conditions. Upon the sensing of a condition that calls for an increase in the quantity of refrigerant, a second flow path is opened which supplies additional refrigerant from the condenser to the evaporator. Another example of a refrigerant adjusting system is described in copending U.S. patent application Ser. No. 09/244,910, filed Feb. 4, 1999, which is commonly assigned herewith, and which is hereby expressly incorporated by reference herein. In this application, there is disclosed an absorption type machine in which refrigerant is stored in a holding tank that is separate from the condenser sump and that is filled via a refrigerant bleed line. The desired refrigerant concentration is then maintained by releasing refrigerant from the holding tank under the control of a microprocessor in response to the sensing of a need for additional refrigerant.
An example of a refrigerant adjusting system that is specially adapted for use in an absorption type refrigerator is described in U.S. Pat. No. 5,806,325 (Furukawa et al). In that patent there is described an absorption type refrigerator in which a storage reservoir is formed in the condenser by a dam with an array of holes that allows the rate at which refrigerant is released to vary as a function of the rate at which refrigerant condenses and, consequently, as a function of the cooling load that the refrigerator must support.
When an absorption type cooling system is shut down, it is necessary to release into the system, within a time known as the dilution time, a quantity of refrigerant which is sufficient to dilute or reduce the concentration of the absorbent-refrigerant solution within the absorber to a value low enough to prevent crystals of the absorbent from forming therein. The diluting of this solution during the shut down process is known as the dilution cycle of the system. Historically, the additional refrigerant necessary to enable the system to complete its dilution cycle has been provided in various ways. One approach was to pump the additional refrigerant from a specially provided storage tank. This approach is not cost effective, however, not only because of the cost of providing such a storage tank, but also because of the cost of providing the associated pump and pump control circuitry.
Another way of providing the additional refrigerant necessary to complete the dilution process has been to release into the system the contents of the refrigerant storage reservoir or tank that is used as a part of its cooling mode refrigerant adjusting system.
This way of diluting the solution, however, has a deficiency that limits its usefulness. This is that the reservoir outlets and piping through which refrigerant is released during the cooling mode refrigerant adjusting process are too small to allow the refrigerant necessary to complete the dilution process to be released within the available dilution time. As a result, the released refrigerant may not be able to mix with the absorbent-refrigerant solution rapidly enough to prevent crystals from forming in the absorber.
While the above-mentioned deficiency may be overcome by providing circuitry which senses the occurrence of a shut down condition, and which opens valves that controllably increase the rate at which refrigerant is released into the evaporator, the provision of such circuitry and valves substantially increases the cost of the shut down portion of the cooling system. The provision of such control circuitry and valves also increases the complexity of the system and thereby introduces failure modes that decrease the overall reliability thereof.
Another approach for providing the refrigerant necessary for dilution has been that shown in U.S. patent application Ser. No. 09/580,182, filed May 26, 2000 which is commonly assigned herewith and which is expressly incorporated herein by reference. There, a refrigerant storage tank is provided in the condenser for storage during the cooling cycle for release along two flow paths during part load and shut down conditions, respectively.
Finally, there is another common approach wherein the refrigerant is stored in the evaporator sump and the level of the refrigerant is sensed so that when it reaches a certain predetermined level, a solenoid valve is opened and refrigerant is dumped to the solution pump either by gravity feed or by using a refrigerant pump. This approach, of course, requires a sensor, a solenoid valve and possibly an additional refrigerant pump.
It is therefore an object of the present invention to provide an improved refrigeration management apparatus for an absorption system.
Another object of the present invention is the provision in an absorption system for a refrigeration management apparatus which stores refrigerant during the cooling process and selectively releases refrigerant to accommodate part load and shutdown conditions.
Yet another object of the present invention is the provision in an absorption system for the storage of refrigerant in a location other than in the condenser.
These objects and other features and advantages become readily apparent upon reference to the following descriptions when taken in conjunction with the appended drawings.
SUMMARY OF THE INVENTION
Briefly, in accordance with one aspect of the invention, a refrigerant storage tank is placed in the evaporator of an absorption system, in fluid communication with both the condenser and an evaporator sump. During cooling mode operation, liquid refrigerant flows from the condenser to the storage tank by way of a conduit, and from the storage tank to the evaporator sump by way of an opening in the side of the storage tank and by way of overflowing the refrigerant tank during full load operating conditions. The size of the opening is such that, under part load conditions, there is sufficient flow of refrigerant to the sump to prevent cavitation of a refrigerant pump associated with the sump. At shutdown, the opening allows for drainage of the refrigerant storage tank into the sump and for the subsequent overflow of the sump into the absorber so as to sufficiently dilute the absorber solution to prevent the formation of crystals.
In accordance with another aspect of the invention, the condenser is fluidly connected to the refrigerant storage tank by way of a J-tube, which provides a liquid seal between the condenser and the evaporator. Also, a liquid/vapor separator may be provided downstream at J-tube such that any vapor that results from a flashing of the refrigerant can be passed to the absorber, with only liquid refrigerant remaining to be passed to the storage tank.
In accordance with another aspect of the invention, the opening in the side of the refrigerant storage tank is a slot which extends vertically to the bottom of the storage tank such that, upon shutdown, the storage tank drains completely to the evaporator sump.
In accordance with another aspect of the invention, the storage tank is replenished by way of a bleed line from the refrigerant pump rather than from the condenser.
In the drawings as hereinafter described, a preferred embodiment is depicted; however, various other modifications and alternate constructions can be made thereto without departing from the true spirit and scope of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a simplified schematic diagram of a two-stage absorption machine of a type which is known in the art;
FIG. 2 is a simplified schematic diagram of a refrigerant management apparatus as contemplated by the present invention;
FIG. 3 is a simplified schematic illustration of an absorption machine with a refrigerant management system incorporated therein in accordance with the present invention
DETAILED DESCRIPTION OF THE INVENTION
Referring to FIG. 1, there is shown a simplified schematic diagram of an absorption cooling system 10 of one type that is know in the art, in this case a two-stage, series cycle cooling system. Other types of absorption systems may use more or fewer stages, may be able to operate in both a cooling mode and a heating mode, and may use a parallel rather than a series cycle. It will therefore be understood that the cooling system of FIG. 1 comprises only an exemplary one of the many types of absorption systems that might have been used as a descriptive background for the present invention. As will be explained more fully later, the refrigeration management apparatus of the present invention may be applied to the cooling portions any of these types of absorption systems.
Absorption system 10 of FIG. 1 comprises a closed fluidic system which contains a refrigerant that exists in both a vapor phase and a liquid phase, an absorbent, and a solution of the absorbent in the refrigerant. In the following description, it will be assumed that machine 10 employs water as a refrigerant and lithium bromide, which has a high affinity for water, as an absorbent.
Absorption system 10 of FIG. 1 includes an evaporator 20 and an absorber 30 mounted in a side-by-side relationship within a common shell 40 . System 10 also includes a high temperature generator 50 and a low temperature generator 60 for generating refrigerant vapor from the absorbent-refrigerant solution, and condenser 70 for receiving that refrigerant vapor and condensing it to produce liquid refrigerant. Condenser 70 is located immediately adjacent to and above evaporator 20 , and is disposed in side-by-side relationship with low temperature generator 60 within a common shell 80 .
When system 10 is operating in its cooling mode, liquid refrigerant from condenser 70 is supplied to evaporator 20 , where it is vaporized to absorb heat from a fluid, usually water, that is being chilled. The water being chilled is brought through the evaporator through a chilled water line 22 and a heat exchanger assembly, not shown. Vaporized refrigerant developed within evaporator 20 passes to absorber 30 , through a partition P 1 , where it is absorbed by a relatively strong solution to form a relatively weaker solution. Heat developed in the absorption process is taken out of the absorber by cooling water flowing through a cooling water line 32 and a heat exchanger assembly, not shown.
The solution in absorber 30 collects in an absorber sump 34 and is pumped therefrom by a suitable solution pump 36 . Part of this solution is recirculated through interior of the absorber through a spray head 39 to enhance the absorption process. The remainder of the solution passes through a first, low temperature solution heat exchanger 55 and a second, high temperature solution heat exchanger 57 , and is supplied to high temperature generator 50 via solution inlet line 52 thereof. As the solution within high temperature generator 50 is heated by a suitable heat source 53 , refrigerant vapor is driven off and supplied to low temperature generator 60 and condenser 70 through vapor lines 54 and 64 . The heated solution remaining within the high temperature generator then exits through a solution outlet line 56 and is supplied to absorber 30 through a solution inlet line 33 . On the way, this solution passes through heat exchanger 57 , valve orifice 59 , low temperature generator 60 , via inlet and outlet lines 62 and 64 thereof, and heat exchanger 55 to assure that much of the thermal energy stored therein is recovered, thereby reducing the amount of heat that must be supplied by heat source 53 . The machine shown in FIG. 1 may also be provided with an overflow path, which may take the form of a J-tube 67 , through which excess solution within low temperature generator 60 may be supplied to absorber 30 through a suitable inlet 37 .
Refrigerant vapor which is released into condenser 70 via vapor lines 54 and 64 , along with refrigerant vapor which is released into condenser 70 by low temperature generator 60 , via a partition P 2 , is cooled by cooling water flowing through cooling water line 32 and a heat exchanger, not shown. This vapor condenses to form liquid refrigerant which collects in a condenser sump 74 . From condenser sump 74 , the liquid refrigerant flows toward evaporator 20 , under the force of gravity, through a suitable J-tube 75 and refrigerant inlet line 23 , and collects within an evaporator sump 24 .
Liquid refrigerant is pumped out of evaporator sump by a suitable refrigerant pump 26 and supplied through a refrigerant discharge line 28 and an orifice plate 27 to a spray head 29 , which sprays the refrigerant into the interior of the evaporator chamber. There it evaporates as a result of the low pressure maintained therein by absorber 30 , through partition P 1 , to produce the already described cooling effect on fluid, usually water, flowing through chilled water line 22 . The refrigerant vapor then passes through partition P 1 into the interior of evaporator 30 , where it is absorbed by the solution that is pumped from absorber sump 34 by solution pump 36 and sprayed thereover through spray head 39 . The solution that collects within absorber sump 34 as this occurs is then either recirculated through spray head 39 or directed back to high temperature generator 50 , in the manner described earlier, to complete the cycle.
Because cooling systems of the-above-described type are well known to those skilled in the art, the operation of the system of FIG. 1 in its cooling mode will not be further described herein. Because the manner in which the system of FIG. 1 may be modified for operation in a heating mode is also well known to those skilled in the art, the operation of the system of FIG. 1 in a heating mode will also not be described herein.
When system 10 is operating in its cooling mode, it is desirable for the refrigerant-absorbent solution to have a concentration which is relatively high, i.e., to be relatively strong or refrigerant-poor, but which varies over a range of concentrations that fluctuates with the cooling load thereon. More particularly, it is desirable for the concentration of the solution to increase as the cooling load on the system increases. This increase in concentration is preferably accomplished by providing the cooling system with a cooling mode refrigerant adjusting system that causes liquid refrigerant to be withdrawn from the solution, (i.e., withdrawn from active circulation within the system) as the cooling load increases, and which releases liquid refrigerant into the system as the cooling load decreases.
In absorption cooling systems of the type described in unexamined Japanese application 62-178858, in U.S. Pat. No. 5,806,325 (Furukawa et al), and in pending application Ser. No. 09/580,182, the refrigerant adjusting system includes a refrigerant storage reservoir that forms a part of the condenser and may comprise the condenser sump. The present invention, on the other hand incorporates the refrigerant management system as a part of the evaporator as shown in FIGS. 2 and 3. Referring now to FIG. 2, there is shown an evaporator 20 with its associated sump 24 , along with a condenser 70 mounted thereabove in a conventional manner. However, unlike the conventional machine, there is positioned in the top portion of the evaporator 20 , a refrigerant storage tank 80 . The condenser 70 and the refrigerant storage tank 80 are interconnected by a J-tube 85 so as to provide for fluidic communication between the two, while maintaining a liquid seal therebetween.
Formed in the side of the refrigerant storage tank 80 is an opening, 86 , to provide for direct fluidic flow between the storage tank 80 and the evaporator sump 24 below. While the opening is shown as a vertical slot, it may take any of other appropriate forms such as a single round opening on a plurality of openings arranged in horizontal or vertical spacings. As will be seen, the opening 86 preferably extends downwardly to the bottom surface of the tank 80 so that, so long as there is liquid refrigerant in the storage tank 80 , there will be a flow out of a opening 86 and into the evaporator sump 24 . The storage tank 80 has an open top 87 so that, if refrigerant continues to flow into the tank 80 by way of the J-tube 85 after it is full, the tank will overflow, with the refrigerant flowing to the evaporator sump 24 .
In operation, as refrigerant forms in the condenser, it flows to the storage tank 80 by way of the J- tube 85 , but the refrigerant will immediately begin to flow from the slot 86 to the evaporator sump 24 . As the machine continues to operate, the volume of condensate coming from the condenser 70 will exceed that which is flowing from the slot 86 , so that the storage tank 80 will eventually fill up and overflow to the sump 24 . Under part load conditions, however, the supply of condensate from the condenser 70 will not keep up with the flow of refrigerant from the slot 86 , and the level of refrigerant in the tank 80 will drop, but the flow of refrigerant from the slot 86 will continue to flow to the sump 24 so as to provide sufficient refrigerant to prevent the cavitation of refrigerant pump 26 . At shutdown, all of the refrigerant will be drained from the storage tank 80 by way of the slot 86 , thereby filling up the sump 24 and causing it to overflow into the absorber so as to thereby dilute the solution and prevent crystallization from occurring.
As will be understood from the above description, the size of the slot 86 , as well as the volumes of the storage tank 80 and the sump 24 are critical to proper operation of the system. Generally, these are selected such that, at the anticipated the minimum load conditions, there is sufficient refrigerant in the sump 24 to prevent cavitation of the refrigerant pump 26 , at full load operating conditions the storage tank overflows to the sump 24 but the sump 24 does not overflow to the absorber 30 , and at shutdown there is sufficient refrigerant stored in the storage tank 80 that, when it is drained to the sump 24 and overflows to the absorber, there is sufficient refrigerant to lower the concentration of solution in the absorber to prevent crystallization thereof. Also, at 80 percent load, the flow from the slot 86 will be such that it will be exceeded by the flow of refrigerant from the condenser such that the storage tank 80 will overflow to the sump 24 .
Referring now to FIG. 3, the conventional system of FIG. 1 is now shown to include modifications to incorporate the above described refrigerant management apparatus into the system. As will be seen, rather than placing the refrigerant storage tank in the condenser, it is located in the evaporator. In doing so, with the condensed refrigerant passing to the storage tank 80 by way of the J-tube 85 , there will be a tendency for some of the liquid refrigerant to flash to a vapor form as it passes into the tank. This will, in turn, complicate the relative volume relationship as discussed hereinabove. That is, if there is a liquid/vapor mixture passing to the storage tank 80 , the volume of the two phase flow will be substantially greater than it would have been in a single phase form, thereby presenting the tank with a condition in which the volume is exaggerated for that particular operating condition. Accordingly, it is desirable to locate a liquid/vapor separator 90 in the circuit between the J-tube 85 and the storage tank 80 . Any resulting refrigerant vapor can then be conducted along line 91 to the absorber 30 , thereby leaving only liquid refrigerant to flow from the separator 90 to the storage tank 80 .
As an alternative to the supplying of refrigerant from the condenser 70 to the storage tank 80 as described above, the storage tank 80 may be kept supplied with refrigerant by way of a line 93 (shown as the dotted line and FIG. 3) coming from the refrigerant discharge line 28 . With this arrangement, the J- tube 85 and the liquid/vapor separator 90 can be eliminated and, although the feature of ensuring that there is sufficient refrigerant in the evaporator sump at part load, will no longer be available, the feature of diluting the solution at shutdown will operate in the same manner as described above.
Although preferred embodiments of the present invention have been illustrated and described, other changes will occur to those skilled in the art. For example, although the invention has been described with reference to a two-stage, series cycle of absorption cooling system, it could just as well have been described with reference to cooling systems of any of a variety of other types, including a single stage, parallel cycle system, among others. | An absorption provided with a refrigerant management method and apparatus for temporarily storing liquid refrigerant during cooling mode operation and releasing refrigerant to the evaporator sump as needed to prevent refrigerant pump cavitation during periods of part load operation and causing dilution of solution in the absorber when the system is shut down. The refrigerant is stored in a tank located in the evaporator, with the tank fluidly communicating with the evaporator sump both by way of a side opening in the tank and by way of overflowing the tank. Refrigerant replenishment to the tank occurs during normal operation either by refrigerant flow from the condenser or by way of a bleed line from the refrigerant pump. | 5 |
This application is a divisional application of U.S. application Ser. No. 582,517, filed Sep. 13, 1990, now abandoned.
FIELD OF THE INVENTION
This invention relates generally to the manufacture of polycrystalline diamond (PCD) coated substrates having particular application in integrated circuit devices. More particularly, the invention relates to a coated substrate product comprised of a plurality of thick, adherent and coherent polycrystalline diamond (PCD) layers deposited on a substrate having high electrical resistivity, and to a method for producing same.
BACKGROUND OF THE INVENTION
A number of chemical vapor deposition (CVD) techniques including hot filament CVD (HFCVD), RF plasma assisted CVD, microwave plasma assisted CVD, DC plasma assisted CVD and laser assisted CVD methods have been used to deposit thin (1-10 μm), adherent and coherent PCD films on a variety of substrates. However, these methods have not been successful in depositing thick (≧12 μm) PCD films adherently and coherently on metal and ceramic substrates. Furthermore, the films deposited by these techniques have been found to have poor electrical properties, making them unsuitable for the electronics industry.
The electrical properties of PCD films can be greatly improved by depositing them with enhanced crystal orientation in the (220) and (400) planes, as disclosed in a commonly assigned copending patent application, U.S. Pat. Ser. No. 497,161, filed Mar. 20, 1990, now abandoned. These PCD films have been successfully deposited at low as well as high rates on metallic substrates such as molybdenum and ceramics such as silicon with good adhesion. The adhesion has been shown to be extremely good as long as the film thickness is limited to ˜10 μm. Although it is possible to deposit thicker films (>10 μm) at high rates both and silicon, their adhesion to these substrates has been noted to be poor. The PCD films on molybdenum have been found to simply flake off during cooling of the coated specimens from the deposition temperature to room temperature. Likewise, the films on silicon have been noted to be under high stress, causing the coated silicon to disintegrate into pieces. The disadvantages of such thick PCD films are set forth more fully below.
Several attempts have been made by researchers to deposit thick PCD films on metallic and ceramic substrates with limited success. The differences between the coefficients of thermal expansion of diamond and metals cause the thick films to separate from metallic substrates as the coated substrates cool from deposition temperature to room temperature, as reported by Peter Taborek in a recent paper entitled, "Optical Properties of Microcrystalline CVD Diamond," published in SPIE, Vol. 1112, Window and Dome Technologies and Materials, 205-209 (1989).
The thick films have, however, been reported to adhere well to silicon substrate, but they have been found to be under high stress (apparent from the resulting curvature of the substrate). In some cases the stress is great enough to cause the sample to disintegrate into pieces, as reported by D. Morrison and J. A. Savage in a paper entitled, "Optical Characteristics of Diamond Grown by Plasma Assisted Chemical Vapor Deposition," published in SPIE, Vol. 1112, Window and Dome Technologies and Materials, 186-191 (1989). Therefore, there is a need to develop technology to deposit thick PCD film adherently and coherently on metallic and ceramic substrates.
Japanese Kokai Patent No. Sho 63(1988)-307196, published Dec. 14, 1988, discloses a microwave plasma assisted CVD method of manufacturing multi-layered PCD film preferentially oriented in the (220) crystalline direction. In this patent application, the diamond deposition conditions such as the concentration of methane in hydrogen are changed continuously or discontinuously to deposit distinct diamond layers with different properties. For example, the first layer of the microcrystal diamond film with ˜0.1 μm thickness is formed using high concentrations of methane in hydrogen (such as 2%). The second layer is deposited on the first layer with good crystallinity using low concentrations of methane in hydrogen (such as 0.3%). This application does not disclose a method of depositing thick, uniform, adherent and coherent PCD film on a substrate.
U.S. Pat. No. 4,816,286 discloses an HFCVD method for depositing PCD film to a thickness as high as 28 μm on various substrates at deposition rates of about 3 μm per hour and higher; see Examples 1-8 starting at column 5, line 48 through Table 1 bridging columns 7 and 8. It has been found that at this rate of deposition the adhesion of PCD films to the substrates is poor.
Thin (˜10 μm) PCD films are suitable for many applications including low-power, direct-current, or low-frequency devices for dissipating heat from the devices as well as for isolating the devices from the base materials. They are, however, not suitable for high-frequency and/or high-power devices with large areas because of their high capacitance. The desired value of capacitance for these devices is ≦3pF, requiring the use of thick PCD films for these applications. The thickness of a PCD film required for a particular application depends largely upon the device area and can be calculated by the following expression: ##EQU1## where: C=capacitance of PCD film in pF
K=dielectric constant of PCD film (assumed to be 5.5 for diamond)
A=device or chip area (cm 2 )
t=PCD film thickness (cm)
E o =free-space permittivity (8.85×10 -2 pF/cm)
A relationship between PCD film thickness and device or chip area can thus be established by plugging in the values of E o , K and desired capacitance in the above equation. The relationship between film thickness and device area can therefore be represented by the following expression:
t≧0.162 A
This expression can be used to calculate the thickness of PCD film required for devices having different areas, and the calculated values are summarized below. ##EQU2##
These values indicate that ˜10 μm thick PCD films will be suitable only for devices with area <10×10 -3 cm 2 . The devices commonly used by the electronics industry have areas ≧10×10 -3 cm 2 , suggesting that the film thickness has to be ≧16 μm to meet capacitance requirement. Therefore, there is a need for depositing thick PCD films on metallic and ceramic substrates with good adhesion and electrical properties. Further, the surface finish of polycrystalline diamond films can also be enhanced over that of prior art PCD films by depositing diamond crystals with enhanced orientation in at least two directions. This is an important feature in regard to mounting the device on the PCD film.
SUMMARY OF THE INVENTION
The improved multi-layer composite structure of the present invention substantially reduces or eliminates the disadvantages and shortcomings associated with the prior art structures. The invention discloses a coated substrate product comprised of a parent substrate and plurality of separate CVD polycrystalline diamond layers of substantially uniform microstructure and having high electrical resistivity. The layers are deposited using deposition conditions which are substantially different between each cycle. In one embodiment of the present invention, the deposition temperatures are alternated such that at least a 25° C. temperature difference exists between each cycle. In another embodiment of the present invention, the deposition pressures are alternated such that at least a 10 Torr pressure difference exists between each cycle.
The invention also comprises a method for fabricating the multi-layered product. According to the method, the plurality of polycrystalline diamond layers are chemical vapor deposited by an HFCVD technique on metallic and ceramic substrates.
In a more specific embodiment of the present invention, the PCD film is chemical vapor deposited on metallic and ceramic substrates by alternating either the deposition temperatures or deposition pressures in the HFCVD technique, such that the PCD film is deposited with an enhanced crystal orientation, excellent electrical properties, and surface finish. The intensity of (HKL) reflection in the (220) or (311) direction and the (400) direction relative to (111) direction of the PCD films of the present invention are enhanced over that of indistinct grade of diamonds. The diamond films of this invention exhibit particularly high electrical resistivity.
BRIEF DESCRIPTION OF THE DRAWINGS
Further features and advantages of the present invention will become apparent from the following and more particular description of the preferred embodiment of the invention as illustrated in the accompanying drawings, in which:
FIG. 1 is a simplified sectional view of a type of HFCVD reactor for use in carrying out the method of the present invention;
FIGS. 2, 3 and 4 are scanning electron micrographs at 5000 times magnification of compositions comprising PCD films deposited by HFCVD on molybdenum in accordance with the disclosure in copending application, Ser. No. 497,161, filed Mar. 20, 1990; and
FIG. 5 is a scanning electron micrograph at 5000 times magnification of compositions comprising PCD film deposited by HFCVD on silicon in accordance with the disclosure in the co-pending application, U.S. Ser. No. 497,161, filed Mar. 20, 1990.
FIGS. 6, 7, 8 and 9 are scaning electron micrographs at 5000 times magnification of compositions comprising a plurality of PCD films deposited by HFCVD on molybdenum in accordance with the present invention.
FIGS. 10 and 11 are scanning electron micrographs at 3500 and 5000 times magnification respectively, of compositions comprising a plurality of PCD films in cross-section deposited by HFCVD on molybdenum in accordance with the present invention.
DETAILED DESCRIPTION OF THE INVENTION
Thick PCD films can be deposited by carefully manipulating the build-up of stresses in the films. The build-up of stresses in the thick PCD films are controlled by employing one of the following methods:
(1) using low deposition rates (<0.4 μm/hr.), which method and the resulting composition is disclosed and claimed in copending patent application, Ser. No. 582,439, filed Sep. 13, 1990;
(2) periodically interrupting the deposition process by subjecting the coated substrate with a cool-down step, i.e. a step in which the coated substrate is cooled to temperatures substantially below the deposition temperatures, which method and resulting composition is disclosed and claimed in the copending patent application, Ser. No. 582,515, filed Sep. 13, 1990; or
(3) cycling the deposition temperature or other deposition parameters during the deposition of the PCD films, which method and resulting composition is disclosed and claimed herein.
Each of these methods have been found to result in altering the microstructure of the PCD films, thereby helping in depositing thick films with reduced stresses. The thick films deposited by using these methods have been demonstrated to have good surface finish, adhesion and electrical properties.
The composition of the present invention is a multi-layered composite structure which comprises a parent substrate and a plurality of polycrystalline diamond layers. The substrate on which diamond film is deposited comprises a single crystal such as diamond, silicon carbide, silicon, sapphire, and similar materials; a polycrystalline material such as silicon; a metal such as tungsten, molybdenum, titanium, tantalum, copper, and the like; a mixture of metals such an tungsten and molybdenum, tungsten and copper, molybdenum and copper, and the like; a ceramic material such as hot pressed, sintered or chemically vapor produced ceramics including silicon carbide, silicon nitride, polycrystalline diamond, cemented carbides, alumina, and the like or mixtures thereof. The substrate may contain various other layers and structures which constitute integrated circuitry. Such layers and structures may be formed before or after the application of the plurality of polycrystalline diamond layers.
Preferably the PCD layers are chemically vapor deposited on the substrate by means of a cyclic deposition technique such that the diamond layers exhibit enhanced crystal orientation in the (22 ) or (311) and (400) directions. In particular the intensity of (HKL) reflection in the (220) and (400) directions in the films of the present invention are at least 47 and 12 percent, respectively, relative to (111) intensity, which is normalized to 100. The resulting structure thus enables the isolation of circuits and silicon devices from one another and from the base substrate via superior electrical properties of the polycrystalline diamond film and exhibits a superior surface finish by substantially reducing the faceted crystals.
In the preferred embodiment of the invention, the polycrystalline diamond layers are chemically vapor deposited on a single crystal, a polycrystalline material, a hard metal, mixtures of metals, ceramic substrates or mixtures thereof, such that the polycrystalline diamond film exhibits enhanced crystal orientation in either the (220) or the (311) direction and the (400) direction over that of industrial grade diamonds.
By the phrase "chemically vapor deposited," it is meant the deposition of a layer of polycrystalline diamond resulting from the thermal decomposition of a mixture of hydrogen and carbon compounds, preferably hydrocarbons, into diamond generating carbon atoms preferentially from the gas phase activated in such a way as to avoid substantially the deposition of graphitic carbon. The specific types of carbon compounds useful in this method include C 1 -C 4 saturated hydrocarbons such as methane, ethane, propane and butane; C 1 -C 4 unsaturated hydrocarbons such as acetylene, ethylene, propylene and butylene; gases containing C and 0 such as carbon monoxide and carbon dioxide; aromatic compounds such as benzene, toluene, xylene, and the like; and organic compounds containing C, H, and at least one of oxygen and/or nitrogen such as methanol, ethanol, propanol, dimethyl ether, diethyl ether, methylamine, ethylamine, acetone, and similar materials (a detailed list of organic compounds that can be used to deposit a diamond layer with enhanced crystal orientation is provided in U.S. Pat. No. 4,816,286, which patent is incorporated herein by reference). The organic compound can be in admixture with water as described in Japanese Kokai Patent No. Sho 64(1989)24093, published Jan. 26, 1989. The concentration of carbon compounds in the hydrogen gas can vary from about 0.1% to about 5%, preferably from about 0.2% to 3%, and more preferably from about 0.5% to 2%. The resulting diamond film in such a deposition method is in the form of adherent individual crystallites or a layer-like agglomerates of crystallites substantially free from intercrystalline adhesion binders.
The total thickness of the plurality of polycrystalline diamond layers can be at least about 12 μm. Preferably, the total thickness of the diamond layers is about 12 μm to 250 μm. Still more preferably, it is about 25 μm to about 130 μm.
The polycrystalline diamond films of the present invention may be deposited in the preferred method by using an HFCVD reactor such as reactor 1 illustrated in FIG. 1. The HFCVD technique involves activating a feed gaseous mixture containing a mixture of hydrocarbon and hydrogen by a heated filament and flowing the activated gaseous mixture over a heated substrate to deposit a first layer polycrystalline diamond film during the first of two alternating deposition temperature cycles of at least one set of cycles. Alternatively, the deposition temperatures may remain constant and the pressures may be alternated for at least one set of cycles. The feed gas mixture, containing from 0.1 to about 5% hydrocarbon in hydrogen, is thermally activated under sub-atmosphere pressure (≦100 torr) to produce hydrocarbon radicals and atomic hydrogen by using a heated filament made of W, Ta, Mo, Re or a mixture thereof. The filament is electrically heated to a temperature ranging from about 1800° to 250° C. The substrate on which the first layer of PCD film is to be deposited is heated to a temperature ranging from about 650° to 825° C. The control of substrate or deposition temperature at or below 825° C. is critical for depositing polycrystalline diamond films with enhanced crystal orientation, excellent electrical properties, and excellent surface finish. The use of deposition temperatures above 825° C. has been found to result in polycrystalline diamond crystals with random orientation. The use of deposition temperatures below 650° C., on the other hand, has been found to result in deposition of diamond films at extremely low and impractical rates.
After a period of at least 3 hours of polycrystalline diamond deposition time for the first cycle, the electrical charge of the filament is controlled in such a manner that there is a minimum ΔT of 25° C. in the deposition temperature from that used in the first cycle. Alternatively, the deposition temperatures may remain constant and the deposition pressure may be varied by at least 10 Torr. The second cycle is continued for at least an additional 3 hours. The HFCVD sets of alternating cycles are continued if the desired total thickness of PCD is not achieved after one set.
The deposition temperature in the second cycle can be higher or lower by at least 25° C. than the first cycle, as long as it is less than 825° C. and greater than 650° C. Alternatively, the deposition pressure in the second cycle can be higher or lower by at least 10 Torr than the first cycle, as long as it is less than 100 Torr and greater than 20 Torr.
When the desired thickness has been achieved, the reactive gaseous mixture is stopped and an inert gas, i.e. argon, helium and the like, is passed over said coated substrate while the filament remains electrically charged for a period of time to purge the activated gaseous mixture from the reactor and then the coated substrate is cooled by removing the charge from the filament while continuing to pass the inert gas over the substrate.
Referring now to FIG. 1, HFCVD reactor 1 for chemical vapor depositing a first layer of a PCD film onto substrates 7 and then for depositing at least an additional layer at substantially different deposition conditions onto the coated substrates comprises a gas dispersion system 25, a filament network 26 and an apertured support plate 27. Gas dispersion system 25 and apertured support plate 27 are oriented within reactor 1 so that their surfaces are perpendicular to the axis of the gas flow through the reaction zone 28. Substrates 7 to be coated are supported by the apertured support plate 27 which rests on an apertured substrate heater 29. Substrate heater 29 is attached to adjustable rods 30, which are mounted to the reactor base 31. Substrate heater 29 is provided with lead 32 to which an electrical heating current is conducted from a suitable heat source 33. Substrate heater 29 is also provided with a thermocouple 38 to measure substrate temperature and a connecting electrical lead 39 through which the thermocouple output is transmitted to an external read-out or recorder/controller 40. To accurately record and control the temperature of the plurality of substrates 7 within the critical range of the method of the present invention, the tip of the thermocouple 38 is placed immediately adjacent to the top surface of one of the substrates, as shown in FIG. 1.
The ends of reactor 1 are enclosed by removable bottom plate 31 and top plate 42 which isolate reactor 1 such that the interior can be evacuated without significant inward leakage from the surrounding ambient atmosphere. In order to regulate the gas pressure within reactor zone 28 and remove reaction product gases, bottom plate 31 is provided with an opening 43 therein through which an exhaust port tube 44 is suitably connected to a vacuum pump 45. A vacuum gauge 46 is connected in the line thereto for indicating the pressure within the reactor chamber. By properly operating the vacuum pump 45, the gas pressure within the reactor chamber may be regulated as desired.
A gas inlet tube 47 is provided which extends through top plate 42. Gas inlet tube 47 is suitably connected to gas dispersion system 25 by means of a gas feed line 48. Gas inlet tube 47 is connected to a gas feed system (not shown) to introduce reactant gases into the reactor at desired flow rates.
Support plate 27 contains apertures 54 and heater 29 contains apertures 56 in heater 29 aligned with apertures 54 as shown in FIG. 1 to provide a means of flowing the reactant gas through the support plate 27 to reduce the extent of radial (stagnation point) flow adjacent to the substrates 7 and improving coating uniformity thereon. Support plate 27 and the substrate heater 29 assembly are provided with adjustable support rods 30 for varying the distance between substrates 7 and filament network 26, the support rods 30 consisting of threaded posts with lock nuts 60 removably secured thereon.
With the noted reactor apparatus, reactant gas is introduced into the reactor chamber through gas inlet tube 47 and gas feed line 48. Gas feed line 47 is connected to gas dispersion system 25 which introduces the reactant gas into reaction zone 28 of the reactor with substantially uniform axial gas velocity and temperature. Gas dispersion system 25 is supported within the reactor by a pair of adjustable rods 73, suitably connected to reactor cap 42; rods 73 consisting of threaded post with suitable lock nuts 70 removably secured thereon.
Gas dispersion system 25 consists of a thin housing 74 with an apertured bottom surface 75 to introduce and uniformly distribute the reactant gas over filament network 26.
Filament network 26 is also supported in reaction zone 28 by one of the adjustable rods 73. Filament network 26 is provided with lead 76 to which the heating current is conducted from a suitable heat source 77. Filament network 26 extends transversely in reaction zone 28 of the reactor and is oriented such that the maximum cross-sectional area of filament network 26 is perpendicular to the axis of the gas flow in reaction zone 28.
Additional details of the type of reactor system used in the method of the present invention are found in the commonly assigned copending application, Ser. No. 497,159, filed Mar. 20, 1990, now abandoned; the detailed description of which is incorporated herein by reference.
The controls and examples which follow illustrate the method of the invention and of the coated substrate products produced thereby. The examples are for illustrative purposes only and are not meant to limit the scope of the claims in any way.
PRE-CONDITIONING OF A NEW FILAMENT
A new tantalum filament made of 1 mm diameter and 21.6 cm long wire was fabricated and placed in the small scale HFCVD reactor described above. The total surface area of the filament was ˜8.5 cm 2 . It was carburized in the reactor using a preferred procedure. The procedure involved heating the filament to ˜1800° C. in the presence of 100 sccm flow of 1% CH 4 in H 2 at 30 torr. The filament temperature was increased in steps of 50° C. every 30 minutes until a temperature of ˜2200° C. was reached. This temperature was maintained for 30 minutes. The temperature and flow rate of 1% CH 4 in H 2 were then reduced to 2100° C. and 20 sccm, respectively, and maintained for another 12 hours. The filament power was then turned off and it was cooled in flowing helium gas. The surface of the filament was carburized well, as evidenced by gold color of TaC. No signs of filament bending were noted during and after carburization. Additionally, no signs of graphitic carbon deposit were seen on the filament.
The filament carburization procedure described above was used prior to using a new filament for depositing PCD films on metallic and ceramic substrates in all the controls and examples described below. In some of these controls and examples a used tantalum filament (filament used previously in depositing PCD films in one or more experiments) was utilized for depositing PCD films. In no case was a virgin tantalum filament used for depositing PCD films.
CONTROLS
A number of control experiments were carried out to deposit PCD films using the HFCVD technique described above in which the deposition parameters were changed to deposit thin as well as thick films.
CONTROL 1
Two 1.35 in. long×0.387 in. wide×0.062 in. thick molybdenum specimens were placed in the HFCVD reactor described above. The specimens were pre-etched for 3 hours in an ultrasonic bath using a slurry of ˜80 μm diamond powder in ethanol. They were then heated to ˜780° C. temperature using a filament made of ˜1 mm diameter tantalum wire, which was pre-carburized, placed ˜10 mm above the specimens and heated to ˜2160° c. temperature using an AC power supply. The filament temperature was determined by using a dual wavelength pyrometer. The specimen temperature, however, was determined by placing a thermocouple next to its top surface as shown in FIG. 1. A flow of 10 sccm of 1% CH 4 in H 2 was passed through the reactor for 15 hours to deposit polycrystalline diamond coating on molybdenum specimens, as shown in Table 1. After the deposition time of 15 hours, the flow of feed gas was switched from 10 sccm of 1% CH 4 in H 2 to 50 standard cubic centimeters per minute (sccm) of He. The filament power was turned off after 1/2 hour and the coated specimens were cooled under flowing He gas. The molybdenum specimens were deposited with ˜7 μm thick, adherent and coherent PCD film on the top of ˜4 μm thick molybdenum carbide interlayer, which was formed in situ. The rate of PCD deposition in this example was ˜0.47 m/hour. The film exhibited excellent electrical resistivity, as shown in Table 1.
Control 1 showed that thin PCD films can be deposited adherently and coherently on metallic substrates using the conventional HFCVD technique.
CONTROL 2
The PCD deposition experiment described in Control 1 was repeated using similar reactor design, type of specimens, and deposition conditions with the exception of using 790° C. specimen temperature, as shown in Table 1. The specimens were pre-etched only for 1 hour in an ultrasonic bath using a slurry of ˜80 μm diamond powder in ethanol. The specimens were deposited with ˜9 μm thick, adherent and coherent PCD film at the top of ˜3 μm thick molybdenum carbide interlayer, as shown in Table 1. The deposition rate was ˜0.60 μm/hr. The PCD film exhibited excellent electrical resistivity.
This control indicated that reducing the etching time from 3 hours to 1 hour was not detrimental to the adhesion of PCD film on molybdenum. It also showed that thin PCD films (˜9 μm) can be deposited on metallic substrates adherently and coherently using the conventional HFCVD technique.
CONTROL 3
The PCD deposition experiment described in Control 2 was repeated with the exception of using 22 hrs. of deposition time instead of 15 hours, as shown in Table 1. The specimens were, once again, pre-etched only for 1 hour in an ultrasonic bath using a slurry of ˜80 μm diamond powder in ethanol. The specimens were deposited with ˜11 μm thick, adherent and coherent PCD film at the top of 3 μm thick molybdenum carbide interlayer (see Table 1). The deposition rate was ˜0.50 μm/hour. The PCD film had fairly good surface finish, as shown in FIG. 2.
This control, once again, indicated no detrimental effects of reducing the etching time from 3 hours to 1 hour in depositing a thin PCD film on molybdenum. It also showed that thin PCD films (˜11 μm) can be deposited on metallic substrates adherently and coherently using the conventional HFCVD technique.
CONTROL 4
The PCD deposition experiment described in Control 1 was repeated using similar reactor design, type of specimens, and deposition conditions with the exception of using 800° C. specimen temperature, as shown in Table 1. The specimens were pre-etched for 2 hours in an ultrasonic bath using a slurry of ˜80 μm diamond powder in ethanol. The specimens were deposited with ˜12 μm thick PCD film at the top of ˜5 μthick molybden carbide interlayer. The deposition rate in this experiment was ˜0.8 μm/hour, which was higher than that noted in Controls 1 to 3. The PCD film on both specimens spalled off completely probably due to build-up of stresses. The film had enhanced crystal orientation in (220), (311) and (400) directions relative to (111) direction, as shown in Table 2.
This control showed that PCD films with thicknesses of ˜12 μm or greater can not be deposited adherently and coherently on metallic substrates using the conventional HFCVD technique.
CONTROL 5
The PCD deposition experiment described in Control 4 was repeated with the exception of using 66 hours of deposition time. One of the specimens was preetched for 3 hours in an ultrasonic bath using a slurry of ˜80 μm diamond powder in ethanol. The other specimen, on the other hand, was etched by polishing it with a paste containing ˜3 μm diamond particles. The PCD film on each of these specimens was ˜45 μm thick, resulting in a deposition rate of ˜0.68 μm/hr., which was lower than noted in Control 4 but higher than those of Controls 1 to 3. The PCD film had a decent surface finish, as shown in FIG. 3. However, the PCD film on these specimens spalled-off completely, probably due to build-up of stresses by high deposition rate. The film showed enhanced crystal orientation in (220) and (400) directions relative to (111) direction as shown in Table 2.
This control, once again, showed that PCD films with thicknesses ≧12 μm can be deposited adherently and coherently on metallic substrates using the conventional HFCVD technique.
CONTROLS 6A and B
One 1.35 in. long×0.387 in. wide×0.062 in. thick molybdenum specimen (Control 6A) and one 1.35 in. long×0.387 in. wide silicon piece (Control 6B) were placed in a reactor described in Control 1. These specimens were pre-etched for 4 hours in an ultrasonic bath using a slurry of ˜80 μm diamond powder in ethanol. The specimens were heated to ˜790° C. temperature using a filament made of ˜1 mm diameter tantalum wire, which was placed ˜10 mm above the specimens and heated to ˜2170° C. temperature using an AC power supply. The filament was pre-carburized using the procedure described earlier. The filament and specimen temperatures were determined using the techniques described in Control 1. A flow of 10 sccm of 1% CH 4 in H 2 was passed through the reactor for 18 hours to deposit PCD film on molybdenum and silicon specimens, as set forth in Table 1. After the deposition time, the flow of feed gas was switched from 10 sccm of 1% CH 4 in H 2 to ˜50 sccm of He. The filament power was turned off after 1/2 hour and the coated specimens were cooled under flowing He gas. The molybdenum specimen was deposited with ˜7 μm thick, adherent and coherent PCD film at the top of ˜3 μm thick carbide interlayer, which was formed in situ. The deposition rate was ˜0.39 μm/hr., which was slightly lower than that noted in Controls 1-5. The silicon specimen was also deposited with ˜7 μm thick adherent and coherent PCD film at the top of ˜1 μm thick carbide interlayer. The coated silicon specimen was, however, bent a little due to build-up of stresses in the film during coating and upon cooling.
Controls 6A and B showed that thin PCD films (<12 μm) can be deposited adherently and coherently on metallic and ceramic substrates using the conventional HFCVD technique.
CONTROLS 7A and B
The PCD deposition experiment described in Controls 6A and B were repeated using similar reactor design, type of specimens, and deposition conditions except for using 780° C. specimen temperature and 16 hours deposition time. The specimens were pre-etched for 2 hours in an ultrasonic bath using a slurry of ˜80 μm diamond powder in ethanol. The molybdenum specimen (Control 7A) was deposited with ˜7 μm thick adherent and coherent PCD film at the top of ˜3 μm thick carbide interlayer as set forth in Table 1. The silicon specimen (Control 7B) was also deposited with ˜7 μm thick adherent and coherent PCD film at the top of ˜1 μm thick carbide interlayer. The deposition rate both on molybdenum and silicon was ˜0.44 μm/hr. The coated silicon specimen was, once again, bent a little due to build-up of stresses in the film during coating and upon cooling. The PCD films on molybdenum and silicon specimens had decent surface finish, as shown in FIGS. 4 and 5. The film had enhanced crystal orientation in (220) and (400) directions relative to (111) direction, as shown in Table 2.
Controls 7A and B showed that thin PCD films (<12 μm) with good surface finish can be deposited adherently and coherently on metallic and ceramic substrates using the conventional HFCVD technique.
CONTROLS 8A and B
The PCD deposition experiment described in Controls 7A and B were repeated except for using 60 hours deposition time. The specimens were pre-etched for 3 hours in an ultrasonic bath using a slurry of ˜80 μm diamond powder in ethanol. The thickness of PCD film on molybdenum and silicon specimens was ˜32 μm, resulting in deposition rates of ˜0.53 μm/hr. for each of Controls 8A and B as summarized in Table I, which was very similar to that noted in Controls 1 to 3. The film on molybdenum spalled-off completely. The film spallation could be related to build-up of stresses due to high deposition rate or deposition of thick coating. The film adhered well to silicon, but the coated specimen was bent considerably due to build-up of stresses during coating and upon cooling. In fact, the coated silicon specimen disintegrated into pieces while removing from the reactor.
Control 8A and B showed that thick PCD films, i.e., greater than 11 μm, can not be deposited adherently and coherently on metallic and ceramics substrates using the conventional HFCVD technique.
CONTROL 9
Two 1.35 in. long×0.387 in. wide×0.062 in. thick molybdenum specimens were placed in a reactor shown in FIG. 1. The specimens were pre-etched for 1 hour in an ultrasonic bath using a slurry of ˜80 μm diamond powder in ethanol. The specimens were heated to ˜740° C. temperature using a filament made of ˜1.5 mm diameter tantalum wire placed ˜10 mm above the specimens. The filament was heated to ˜1980° C. temperature using an AC power supply. The filament was pre-carburized using the procedure described earlier. The filament and specimen temperatures were determined using the techniques described in Control 1. A flow of 10 sccm of 1% CH 4 in H 2 was passed through the reactor for 20 hours to deposit PCD film on molybdenum specimens, as shown in Table 1. After the deposition time, the flow of feed was switched from 10 sccm of 1% CH 4 in H 2 to ˜ 50 sccm of He. The filament power was turned off after 1/2 hour and the coated specimens were cooled under flowing He gas. The molybdenum specimens were deposited with ˜4 μm thick, adherent and coherent PCD film at the top of ˜2 μm thick carbide interlayer. The deposition rate was ˜0 2 μm/hr., which was considerably lower than noted in Controls 1 to 8. The PCD film had excellent electrical resistivity, as shown in Table 1.
This control again showed that thin PCD films exhibiting excellent electrical resistivity can be deposited adherently and coherently on metallic substrates using the conventional HFCVD technique.
CONTROL 10
The PCD deposition experiment described in Control 9 was repeated using similar reactor design, pre-etching technique, and deposition conditions except for using silicon pieces and 750° C. specimen temperature. The silicon specimens were deposited with ˜4 μm thick adherent and coherent PCD film at the top of ˜1 μm thick carbide interlayer, which was formed in situ. The deposition rate was ˜0.20 μm/hr. The PCD film had excellent electrical resistivity, as shown in Table 1. The coated specimens were however bent slightly due to build-up of stresses during coating and cooling. The film had enhanced crystal orientation in (311) and (400) directions relative to (111) direction, as shown in Table 2.
This control again showed that thin PCD films with excellent electrical resistivity can be deposited on ceramic substrates adherently and coherently using the conventional HFCVD technique.
CONTROL 11
Two 1.35 in. long×0.387 in. wide×0.062 in. thick molybdenum specimens were placed in the same reactor used in the foregoing controls. The specimens were pre-etched for 3 hours in an ultrasonic bath using a slurry of ˜80 μm diamond powder in ethanol. The specimens were heated to ˜800° C. temperature using a filament made of ˜1.25 mm diameter tantalum wire placed ˜10 mm above the specimens. The filament was heated to ˜2180° C. temperature using an AC power supply. The filament was pre-carburized using the procedure described earlier. The filament and specimen temperatures were determined using the techniques described in Control 1. A flow of 10 sccm of 1% CH 4 in H 2 was passed through the reactor for 20 hours to deposit PCD film on molybdenum specimens (see Table 1). After the deposition time, the flow of feed gas was switched from 10 sccm of 1% CH 4 in H 2 to ˜50 sccm of He. The filament power was turned off after 1/2 hour and the coated specimens were cooled under flowing He gas. The molybdenum specimens were deposited with ˜6 μm thick, adherent and coherent PCD film at the top of ˜2 ˜m thick carbide interlayer, which was formed in situ. The deposition rate was ˜0.3 μm/hr. The film showed good electrical resistivity, as shown in Table 1.
This control again showed that thin PCD films can be deposited adherently and coherently on metallic substrates using the conventional HFCVD technique.
CONTROL 12
The PCD deposition experiment described in Control 11 was repeated using similar reactor design, type of specimens, pre-etching technique, and deposition conditions except for using 5 sccm of 1% CH 4 in H 2 (see Table 1). The specimens were deposited with ˜4 μm thick, adherent and coherent PCD film at the top of ˜2 μm thick carbide interlayer. The deposition rate was ˜0.2 μm/hr. The film showed good electrical resistivity, as documented in Table 1.
This control showed that thin PCD films can be deposited adherently and coherently on metallic substrates using low flow rate of a mixture of 1% CH 4 in H 2 .
CONTROL 13
The PCD deposition experiment described in Control 11 was repeated again using similar reactor design, type of specimens, pre-etching technique, and deposition conditions except for using 15 sccm of 1% CH 4 in H 2 (see Table 1). The specimens were deposited with ˜7 μm thick, adherent and coherent PCD film with good electrical resistivity, as shown in Table 1. The deposition rate was ˜0.35 μm/hr.
This control again showed that thin PCD films can be deposited adherently and coherently on metallic substrates using slightly higher flow rate of 1% CH 4 in H 2 .
CONTROL 14
The PCD deposition experiment described in Control 11 was repeated using similar reactor design, type of specimens, pre-etching technique, and deposition conditions except for using 20 sccm of 1% CH 4 in H 2 (see Table 1). The specimens were deposited with ˜5 μm thick, adherent and coherent PCD film with good electrical resistivity, as shown in Table 1.
This control showed that thin PCD films can be deposited adherently and coherently on metallic substrates using higher flow rate of 1% methane in H 2 .
Controls 1 to 14 showed that thin (<11 μm) PCD films can be deposited adherently and coherently on metallic and ceramic substrates using conventional HFCVD techniques. They also showed that the deposition of adherent and coherent thick (≧12 μm) PCD films can not be achieved by the conventional HFCVD technique. It is believed that the failure of depositing thick PCD films by the conventional HFCVD techniques is related to build-up of stresses, resulting in film delamination.
EXAMPLES
Examples 1 to 7 set forth below illustrate the method of the present invention for depositing thin as well as thick PCD films with good surface finish.
EXAMPLE 1
Two 1.35 in. long×0.387 in. wide×0.062 in. (or 0.015 in.) thick molybdenum specimens were placed in a reactor described in Control 1. The specimens were pre-etched for 3 hours in an ultrasonic bath using a slurry of ˜80 μm diamond powder in ethanol. The specimens were deposited with PCD film using a novel cyclic process. The process involved depositing PCD film in one set consisting of two different cycles. For example, the specimens were heated to 800° C. temperature and deposited with PCD for 10 hours using 10 sccm of CH 4 in H 2 using a tantalum filament made of ˜1.25 mm diameter wire, placed ˜10 mm above the specimens (see Table 3 for details of deposition parameters). The filament was pre-carburized using the procedure described earlier. After 10 hours PCD deposition in the first cycle, the temperature was reduced to 725° C. in about 10 minutes and maintained there to deposit PCD for 10 more hours, thereby providing a total of 20 hours deposition time. This experiment therefore involved 1 set of two deposition cycles of 10 hours each carried out at 800° C. and 725° C., respectively. After the deposition time 20 hours, the flow of feed gas was switched from 10 sccm of 1% CH 4 in H 2 to 50 sccm of He. The filament power was turned off after 1/2 hour and the specimens were cooled in flowing He gas.
The specimens were deposited with ˜6 μm thick, adherent and coherent PCD film with good electrical resistivity, as shown in Table 3. The film had enhanced crystal orientation in (220), (311) and (400) directions relative to (111) direction, as shown in Table 4. The PCD film deposited by the cyclic process had a good surface finish, as shown in FIG. 6. This example therefore showed that presently claimed cyclic process is capable of depositing thin PCD films adherently and coherently on metallic substrates with good surface finish.
EXAMPLE 2
The cyclic deposition experiment described in Example 1was repeated using similar reactor design, type of specimens, pre-etching technique, and deposition conditions except for employing lower temperature 725° C. for 10 hours in the first cycle and higher temperature 800° C. for 10 hours in the second cycle (see Table 3). The total deposition time in this one set of cyclic experiment was 20 hours.
The specimens were deposited with ˜5 μm thick, adherent and coherent PCD film with good resistivity, as shown in Table 3. The film had a decent surface finish, as shown in FIG. 7. This example also showed that thin PCD films can be deposited adherently and coherently on metallic substrates by the present process which is not dependent on whether the temperature during the first deposition cycle is at least 25° C. higher or lower than the temperature during the second cycle.
EXAMPLE 3
The cyclic deposition experiment described in Example 1 was repeated using similar reactor design, type of specimens, pre-etching technique, and deposition conditions except for employing two sets of two deposition cycles conducted at 800° C. and 725° C. for 10 hours each for a total deposition time of 40 hours (see Table 3).
The specimens were deposited with ˜11 μm thick, adherent and coherent PCD film with excellent resistivity, as shown in Table 3. The film had enhanced crystal orientation in (220) and (400) directions relative to (111) direction, as shown in Table 4. This example showed that the thickness of the adherent and coherent PCD coating on the substrates increases as a function of the number of deposition cycles.
EXAMPLE 4
The cyclic deposition experiment described in Example 2 was repeated using similar reactor design, type of specimens, pre-etching technique, and deposition conditions except for employing two sets of two deposition cycles conducted at 725° and 800° C. for 10 hours each for a total deposition time of 40 hours (see Table 3).
The specimens were deposited with ˜12 μm thick, adherent and coherent PCD film with excellent resistivity, as shown in Table 3. The film had a good surface finish, as shown in FIG. 8. This example confirmed the ability of the present method to deposit a thick adherent and coherent PCD coating on metallic substrates by using a novel cyclic process.
EXAMPLE 5
The cyclic deposition experiment described in Example 1 was repeated using similar reactor design, type of specimens, pre-etching technique, and deposition conditions except for employing four sets of two deposition cycles conducted at 800° and 725° C. temperatures (see Table 3). The cycles in the first three sets were carried out for 10 hours each; whereas, the fourth set of cycles were done for 5 hours each. These four sets of cycles provided a total deposition time of 70 hours.
The specimens were deposited with ˜17 μm thick, adherent and coherent PCD film with good electrical resistivity, as shown in Table 3.
EXAMPLE 6
The cyclic deposition experiment described in Example 1 was repeated using similar reactor design, type of specimens, pre-etching technique, and deposition conditions except for employing five sets of two deposition cycles conducted at 800° and 725° C. temperatures. The cycles in the first four sets were carried out for 10 hours each; whereas, the fifth set of cycles were done for 5 hours each. These five sets of cycles provided a total deposition time of 90 hours (se Table 3).
The specimens were deposited with ˜25 μm thick, adherent and coherent PCD film, as shown in Table 3. The film had enhanced crystal orientation in (220), (311) and (400) directions relative to (111) direction, as shown in Table 4. The film had a decent surface finish, as shown in FIG. 9. Cross-sectional micrographs of the film presented in FIGS. 10 and 11 showed disruption in columnar growth pattern of diamond film, resulting in good surface finish.
EXAMPLE 7
The cyclic deposition experiment described in Example 1 was repeated using similar reactor design, type of specimens, pre-etching technique, and deposition conditions except for employing six sets of two deposition cycles conducted at 800° C. and 725° C. temperatures each for 10 hours. These six sets of cycles provided a total deposition time of 120 hours (see Table 3).
The specimens were deposited with ˜34 μm thick adherent and coherent PCD film, as shown in Table 3. This example therefore showed that a novel cycling process could be used to deposit thick (˜34 μm) PCD films adherently and coherently on metallic substrates.
CONCLUSIONS
The foregoing examples illustrate that both thin and thick PCD films can be deposited adherently and coherently on metallic and ceramic substrates only by cycling the deposition parameters in the HFCVD technique. They also showed that PCD films with enhanced crystal orientation in (220), or (311) and (400) directions relative to (111) direction, good electrical resistivity, and surface finish can be produced by using the novel cyclic technique.
Without the departing from the spirit and scope of this invention, one of ordinary skill can make various changes and modification to the invention to adapt it to various usages and conditions. As such, these changes and modifications are properly, equitably, and intended to be, within the full range of equivalence of the following claims.
TABLE 1__________________________________________________________________________Control 1.sup.a 2.sup.a 3.sup.a 4.sup.a 5.sup.a 6A.sup.a 6B.sup.a 7A.sup.a 7B.sup.a__________________________________________________________________________Experiment No. 49-1 47-1 55-1 46-1 41-1 44-1 44-1 45-1 45-1Substrate Mo Mo Mo Mo Mo Mo Si Mo SiSubstrate Temp., °C. 780 790 790 800 800 790 790 780 780Filament Temp., °C. 2160 2180 2180 2210 2190 2170 2170 2160 2160Flow Rate of 1% 10 10 10 10 10 10 10 10 10CH.sub.4 in H.sub.2, sccmTotal Pressure, 30 30 30 30 30 30 30 30 30TorrDeposition Time, 15 15 22 15 66 18 18 16 16Hrs.Thickness, μmMolybdenum ˜4 ˜3 ˜3 ˜5 N.D. ˜3 ˜1 ˜3 ˜1CarbideDiamond ˜7 ˜9 ˜11 ˜12 ˜45 ˜7 ˜4 ˜7 ˜7Deposition Rate, 0.47 60 0.50 0.80 0.68 0.39 0.39 0.44 0.44μm/hrResistivity, 1.1 × 10.sup.12 3.2 × 10.sup.11 N.D. N.D. N.D. N.D. N.D. N.D. N.D.Ohm-cmObservations * * * ** ** * * * *__________________________________________________________________________Control 8A.sup.a 8B.sup.a 9.sup.b 10.sup.b 11.sup.c 12.sup.c 13.sup.c 14.sup.c__________________________________________________________________________Experiment No. 53-1 53-1 61-1 71-1 5-3 6-3 7-3 8-3Substrates Mo Si Mo Si Mo Mo Mo MoSubstrate Temp., °C. 790 790 740 750 800 800 800 800Filament Temp., °C. 2170 2170 1980 1980 2180 2160 2170 2180Flow Rate of 1% 10 10 10 10 10 5 15 20CH.sub.4 in H.sub.2, sccmTotal Pressure, 30 30 30 30 30 30 30 30TorrDeposition Time, 60 60 20 20 20 20 20 20Hrs.Thickness, μmMolybdenum N.D. N.D. ˜2 ˜1 ˜2 ˜2 ˜2 ˜2CarbideDiamond ˜32 ˜32 ˜4 ˜4 ˜6 ˜4 ˜7 ˜5Deposition Rate, 0.53 0.53 0.20 0.20 0.30 0.20 0.35 0.25μm/hrResistivity, N.D. N.D. 4.8 × 10.sup.10 3.2 × 10.sup.10 1.3 × 10.sup.10 2.1 × 10.sup.9 1.1 × 10.sup.8 3.1 × 10.sup.8Ohm-cmObservations * ** * * * * * *__________________________________________________________________________ .sup.a The diameter of tantalum wire used for making filament in these experiments was ˜1 mm. .sup.b The diameter of tantalum wire used for making filament in these experiments was ˜1.5 mm. .sup.c The diameter of tantalum wire used for making filament in these experiments was ˜1.25 mm. *Adherent and coherent film. **Film spalled completely N.D. Not determined
TABLE 2______________________________________Crystal Orientation and Average Size of PCD Films INDUSTRIAL GRADE DIA- CONTROLS MOND POWDER.sup.2 4 5 7A 10______________________________________Experiment No. 46-1 41-1 45-1 71-1Intensity of (hkl)reflection relativeto (111).sup.1 %(220).sup.3 25 135 57 130 22(311) 16 19 9 14 26(400).sup.4 8 24 13 22 13______________________________________ .sup.1 The relative intensity of crystals in (111) direction is normalize to 100. .sup.2 PDF 6675 .sup.3 (220) Crystal orientation is parallel to (110) orientation, and therefore crystals are in the same family of planes. .sup.4 (400) Crystal orientation is parallel to (100) orientation, and therefore crystals are in the same family of planes.
TABLE 3__________________________________________________________________________Example 1 2 3 4 5 6 7__________________________________________________________________________Experiment No. 12-3 13-3 15-3 16-3 14-3 32-3 37-3Specimens Mo Mo Mo Mo Mo Mo MoSpecimen Temp., °C.First Cycle 800 725 800 725 800 800 800Second Cycle 725 800 725 800 725 725 725No. of Sets of Cycles 1 1 2 2 4 5 6Flow Rate of 1% 10 10 10 10 10 10 10CH.sub.4 in H.sub.2, sccmTotal Pressure, Torr 30 30 30 30 30 30 30Total Deposition Time, 20 20 40 40 70 90 120Hrs.Thicknesses, μmCarbide Interlayer 3 2 3 3 5 5 6Diamond 6 -5 11 12 17 25 34Resistivity, 1.3 × 10.sup.12 5.1 × 10.sup.10 >1.0 × 10.sup.14 >1.0 × 10.sup.14 5.3 × 10.sup. N.D. N.D.Ohm-cmObservations * * * * * * *__________________________________________________________________________ Note: The diameter of tantalum wire used for making filament in these experiments was ˜1.25 mm. *Adherent and coherent film. N.D. Not determined
TABLE 4______________________________________CRYSTAL ORIENTATION AND AVERAGECRYSTALLITE SIZE OF PCD FILMS Industrial Grade Diamond EXAMPLES Powder.sup.2 1 3 6______________________________________Intensity of (hkl)reflection relativeto (111).sup.1 %(220).sup.3 25 145 48 70(311) 16 23 15 19(400).sup.4 8 32 13 14Average crystaline -- 780 1,400 1,500Size, Å______________________________________ .sup.1 The relative intensity of crystals in (111) direction is normalize to 100. .sup.2 PDF 6675 .sup.3 (220) Crystal orientation is parallel to (110) orientation, and therefore are in the same family of planes. .sup.4 (400) Crystal orientation is parallel to (100) orientation, and therefore are in the same family of planes. | A thick, adherent and coherent polycrystalline diamond (PCD) coated substrate product is disclosed which comprises either a metallic or ceramic substrate and a plurality of separately deposited PCD layers of substantially uniform microstructure and having high electrical resistivity. The method for depositing multi-layers of PCD film onto the substrate comprises chemically depositing at least two separate polycrystalline diamond layers onto the substrate deposition conditions which are substantially different between cycles. The method enables one to deposit PCD films having a thickness of at least 12 microns for applications on flat as well as curved substrates having wide use in the electronics industry. Thick PCT films of this invention have been found to be ideal for dissipating heat from radio frequency (RF) and microwave (MW) devices. | 2 |
CROSS-REFERENCES TO RELATED APPLICATIONS
[0001] This application claims the priority of German Patent Application, Serial No. 10 2015 014 358.1, filed Nov. 6, 2015, pursuant to 35 U.S.C. 119(a)-(d), the content of which is incorporated herein by reference in its entirety as if fully set forth herein.
BACKGROUND OF THE INVENTION
[0002] The invention relates to a method for producing a node structure with at least two profile components that are in particular made of a fiber reinforced plastic composite material.
[0003] The following discussion of related art is provided to assist the reader in understanding the advantages of the invention, and is not to be construed as an admission that this related art is prior art to this invention.
[0004] Vehicle body structures formed from profiles are known from the state of the art. Thus for example DE 44 23 642 C1 discloses a motor vehicle support frame which is composed of individual separately pre-manufactured frame profile components. The frame profile components can each be configured as fiber composite profile pieces, for example with a rectangular hollow profile cross section and in the consolidated or cured state are respectively connected framework-like via node pieces, which are also made of a fiber composite material, to form an integral frame structure. For manufacture of a node piece the frame profile components that are o be connected are inserted into the receiving pockets of a pre-manufactured fiber preform. In a forming tool the node piece is then generated under the influence of pressure and heat.
[0005] It would be desirable and advantageous to provide an improved method for producing a node structure.
SUMMARY OF THE INVENTION
[0006] According to one aspect of the present invention a method for producing a node structure includes providing at least two pre-manufactured profile components having respective profile ends provided with corresponding abutment surfaces; positioning the profile ends in a pressing tool so that a homogenous gap is formed between the abutment surfaces; performing a pressing process in the presence of a fiber-containing plastic mass in the pressing tool for generating a connecting node that form fittingly connects the profile ends, wherein the fiber containing plastic mass also enters into the gap.
[0007] A further independent patent claim sets forth a vehicle body, in particular for a passenger car with a frame (space frame) that is constructed from profile components and with at least one node structure according to the invention. Preferably multiple profile components that form a frame section (for example the rear section front section or midsection structure) are made of fiber plastic composite material. These are in particular exclusively hollow profile components, which are connected with each other by means of node structures according to the invention.
[0008] The profile ends of the profile components to be connected in a connecting node are configured with corresponding abutment surfaces, which means surface areas that face each other or confront each other in the connecting node and which in case of stress also serve as force transmission surfaces. The corresponding abutment surfaces can for example be configured as straight slanted surfaces, as concave and convex surfaces (or at least having concave or convex surface portions), as waved surfaces, as stepped surfaces and/or as surfaces that can be nested in each other, which is the subject matter of advantageous refinements.
[0009] The gap between these abutment surfaces makes it possible that during the pressing process the fiber containing plastic mass, which is used for generating the connecting node, is also pressed between these abutment surfaces so that the node-side profile ends are optimally surrounded by the fiber containing plastic mass and thereby are integrated in a form fitting or also materially bonding manner. A homogenous or uniform gap ensures that the fiber containing plastic mass can fully fill the gap and that at any point of the gap substantially the same connecting properties are generated. A non uniform gap may for example lead to an asymmetric force flux in the event of stress on the produced node structure.
[0010] The invention has many advantages. For example in the method according to the invention no pre-manufactured fiber prefrom, such as described in DE 44 23 643 C1, is required. Furthermore a node structure produced with the method according to the invention has excellent strength, stiffness and crash stability while also being lightweight.
[0011] According to another advantageous feature of the invention the gap has a substantially constant width of at least 0.5 mm and at most 2.0 mm. The minimal gap width of at least 0.5 mm ensures a distance between the abutment surfaces that permits flow so that the profile ends positioned in the pressing tool can be ideally surrounded by the fiber containing plastic mass and thereby integrated in a form fitting/materially bonding manner. The maximal gap width of at most 2.0 mm ensures that in the produced connecting node the paths of force flux between the connected profile ends and their abutment surfaces are short.
[0012] After the curing of the fiber containing plastic mass the pressing tool can be opened and the produced node structure removed. This node structure includes at least two profile components, in particular made of fiber plastic composite material, and a connecting node made of fiber plastic composite material or fiber containing plastic mass, and in particular short fiber containing plastic mass, in which the profile components are connected with each other at their profile ends (or at their node side profile ends in a form fitting and optionally materially bonding manner, wherein the profile ends connected in the connecting node are configured with corresponding abutment surfaces and these abutment surfaces are spaced apart from each other by a uniform gap (i.e. with substantially constant gap width) that is filled with fiber containing plastic mass. The node structure is thus an assembly made of at least two profile components.
[0013] The term profile component means a longitudinal rod-like component with a defined cross sectional shape (profile), which can have a straight or also curved or bent axial extent. At least one profile component can also be a tubular hollow profile component with a closed cross section and with at least one profile chamber. The corresponding profile and hollow profile components are in particular made of consolidated fiber plastic composite material. The fibers can be carbon fibers, glass fibers and/or other fibers. Preferably they are long fibers, which are, for example also in a layered construction, arranged in accordance with a load path. The plastic material (matrix material) can be a thermoset or thermoplastic.
[0014] The profile components can be pre-manufactured components, which are produced in a prior manufacturing process, optionally also by a supplier. The provision of these components includes for example confectioning, preparation, cleaning and/or testing of the profile components to be connected. The provision includes optionally also production of the abutment surfaces for example by mechanical processing, in particular by cutting and/or milling, wherein the abutment surfaces have to be produced at the lasted prior to insertion and positioning of the profile ends in the pressing tool.
[0015] According to another advantageous feature of the invention, the profile components are produced from pre-manufactured profile semi-finished products (in particular rod products). It is also conceivable however to directly produce the profiles or profile components for example by pultusion (or optionally also by coiling or braiding). The profile components can be made of the same fiber reinforced plastic composite material or of different fiber reinforced plastic composite materials.
[0016] According to another advantageous feature of the invention, at least one profile component of a node structure according to the invention is a hollow profile component made of fiber reinforced plastic composite material. In particular all profile component of a node structure according to the invention are hollow profile components made of fiber reinforced plastic composite material.
[0017] The plastic mass that generates the connecting node can be a thermoset (resin) or a thermoplast. The fibers can preferably be short fibers (carbon fibers, glass fibers and/or other fibers, also mixed fibers and in particular recycled fibers) with a length of for example 1 mm to 100 mm, preferably 2 mm to 50 mm, and in particular 3 mm to 25 mm. Preferably the fiber-containing plastic mass used for generating the connecting node is adjusted to the fiber reinforced plastic composite material of the profile components or hollow profile components to be connected.
[0018] The fiber-containing plastic mass for generating the connecting node can be introduced into the tool cavity prior to closing the pressing tool. The fiber-containing plastic mass for generating the connecting node can also be introduced into the tool cavity after closing the pressing tool by injection (similar to injection molding of the RTM technology).
[0019] As described above at least one of the profile components can be a hollow profile component, wherein in particular it is provided that the node-side open profile end of this hollow profile component is closed by means of a closing element in order to prevent the fiber containing plastic mass from entering the hollow profile component during the pressing process. The closing element that is to be applied at the latest prior to inserting and positioning of the hollow profile component in the pressing tool is for example a cover, in particular made of fiber plastic composite material, or a stopper-like closing element made of a plastic foam material, which is in particular glued into the open profile end.
[0020] According to another advantageous feature of the invention, the profile components and/or hollow profile components to be connected in a connecting node can have different cross sections or cross sectional dimensions and/or different wall thicknesses or wall strengths at least at their profile ends that are to be connected or at their node-side end sections.
[0021] According to another aspect of the invention a node structure for a vehicle body, includes at least two profile components having respective profile ends configured with respective corresponding joining surfaces; and a connecting node in which the profile components are form fittingly connected with each other at the respective profile ends, said respective profile ends being spaced apart from each other by a homogenous gap which is filled with a fiber-containing plastic mass.
[0022] The node structure can be manufactured with the method according to the invention.
[0023] According to another aspect of the invention a vehicle body, includes a frame, wherein the frame includes profile components having respective profile ends configured with respective corresponding joining surfaces, and a connecting node in which the profile components are form fittingly connected with each other at the respective profile ends, wherein the respective profile ends are spaced apart from each other by a homogenous gap which is filled with a fiber-containing plastic mass.
BRIEF DESCRIPTION OF THE DRAWING
[0024] Other features and advantages of the present invention will be more readily apparent upon reading the following description of currently preferred exemplified embodiments of the invention with reference to the accompanying drawing, in which
[0025] FIG. 1 shows in a perspective view a vehicle rear section structure made of hollow profile components;
[0026] FIG. 2 shows a perspective view of a node structure belonging to the vehicle rear section structure of FIG. 1 ;
[0027] FIG. 3A shows in multiple sectional views possible configurations of abutments surfaces on two hollow profile components to be connected during the production of the node structure of FIG. 2 ;
[0028] FIG. 3B shows a sectional view of another possible configuration of an abutment surface on two hollow profile components to be connected during the production of the node structure.
[0029] FIG. 3C shows a sectional view of another possible configuration of an abutment surface on two hollow profile components to be connected during the production of the node structure.
[0030] FIG. 3D shows a sectional view of another possible configuration of an abutment surface on two hollow profile components to be connected during the production of the node structure.
[0031] FIG. 4 shows a sectional view of possible configurations of abutment surfaces of three hollow profile components to be connected during the production of the node structure of FIG. 2 ; and
[0032] FIG. 5 shows in sectional view steps of the production of connecting nodes during the production of the node structure of FIG. 2 .
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0033] Throughout all the Figures, same or corresponding elements may generally be indicated by same reference numerals. These depicted embodiments are to be understood as illustrative of the invention and not as limiting in any way. It should also be understood that the figures are not necessarily to scale and that the embodiments are sometimes illustrated by graphic symbols, phantom lines, diagrammatic representations and fragmentary views. In certain instances, details which are not necessary for an understanding of the present invention or which render other details difficult to perceive may have been omitted.
[0034] The vehicle structure or vehicle rear section structure 100 show in FIG. 1 is a part of a frame of a vehicle body. The vehicle rear section structure 100 includes multiple separately pre manufactured hollow profile components 120 , 120 a , 130 , 130 a, 140 , 140 a and 150 made of fiber plastic composite material, wherein these are so called pultrusion profiles whose profile ends are fixedly connected with each other on connecting nodes or node sites 160 and 160 a. typically the hollow profile components 120 , 120 a, 130 , 130 a, 140 , 140 a and 150 are configured differently, i.e., they have depending on the stress different cross sections and/or wall thicknesses and/or are made of different fiber plastic composite materials. The vehicle rear section structure 100 can also have closed profile components and/or profile components that are made of other materials (for example also metal), and which are in particular also integrated in the frame structure 100 via the connecting nodes 160 or 160 a. In spite of its low weight the vehicle rear section structure 100 nevertheless has excellent strength, stiffness and crash stability.
[0035] The hollow profile components that are connected in a connecting node 160 or 160 a form together with this connecting node a node structure in the sense of the invention. FIG. 2 shows such a node structure 110 for the frame region that is position in driving direction x on the left hand side. The integrated node structure 110 includes multiple hollow profile components 12 a, 130 , 140 , and 150 whose profile ends are fixedly connected with each other in a connecting node 160 .
[0036] In the following the production of such a node structure 110 is explained in more detail with reference to FIGS. 3, 4 and 5 , wherein only the connection between the two hollow profile components 120 and 130 is explained. While not illustrated, the hollow profile components 120 and 130 can have different cross sections or cross sectional dimensions and/or different wall thicknesses or wall strengths at least at their end sections 121 and 131 that are to be connected.
[0037] According to the invention the node-side profile ends to be connected are configured with corresponding abutment surfaces. FIGS. 3 A-D show the profile ends 121 and 131 of the hollow profile components 120 and 130 with differently configured abutment surfaces 122 and 132 . The open profile ends 121 and 131 of the hollow profile components 120 and 130 to be connected are closed by closing elements 125 and 135 that are glued in by adhesive 126 or 136 . The closing elements 125 and 135 are made of a plastic foam material, in particular a temperature resistant and pressure resistant hard foam. The abutment surfaces 122 and 132 are preferably only generated after these closing elements 125 and 135 have been glued in, wherein the processing is in particular performed by mechanical processing such as cutting and/or milling. This process can also be referred to as contouring of the profile ends.
[0038] In the embodiment shown in FIG. 3A the node-side profile ends are slanted, i.e., the abutment surfaces 122 and 132 on the profile ends 121 and 131 are configured as straight slanted surfaces. The node-side slanted surfaces 122 and 132 extend slanted (in the sense of non-perpendicular) relative to the longitudinal axes L 1 and L 2 of the hollow profile components 120 and 130 . In the embodiment shown in FIG. 3B the abutment surfaces 122 and 132 are configured as oppositely stepped surfaces. In the embodiment shown in FIG. 3C the abutment surfaces 122 and 132 are configured as waved surfaces with corresponding wave contours (which have concave and convex surface portions). In the embodiment shown in FIG. 3 d the abutment surfaces 122 and 132 are configured as surfaces that can be nested in each other.
[0039] FIGS. 3 A-D show the corresponding abutment surfaces 122 and 132 on the profile ends 121 and 131 to be connected only schematically in 2D representations. Of course the shown abutment surfaces 12 and 132 have correspondingly configured three-dimensional surface contours. Furthermore the embodiments for abutment surfaces shown in FIGS. 3 A-D can be changed or combined to form further embodiments.
[0040] The corresponding abutment surfaces 122 and 132 shown in FIGS. 3 A-D are configured so that they can be arranged with a homogenous gap between them (see FIGS. 4 and 5 ), as explained in more detail below. The abutment surfaces 122 and 132 can be configured so as to enable improved force and/or torque transmission between the associated profile components 120 and 130 in spite of the presence of the gap.
[0041] FIG. 4 shows an embodiment with complexly formed abutment surfaces for three profile ends 121 , 131 and 141 that are to be connected in the connecting node 160 . The corresponding profile ends 121 , 131 and 141 are prepared by mechanical processing, which results in specially formed abutment surfaces or joining surfaces, i.e., corresponding end shapes. The contouring is in particular carried out so that these profile ends 121 , 131 and 141 can be positioned as close as possible to each other while maintaining homogenous gaps S with greatest possible abutment surfaces. Thus within a connecting node multiple abutment surface pairings that are configured with different surface contours and/or with different gap widths can be provided. In this way also more than two profile ends, or even up to five profile ends and more can be brought in very close proximity to each other in a connecting node which saves space while taking later load paths into account.
[0042] For generating the connecting node 160 the closed profile ends 121 and 131 of the hollow profile components 120 and 130 , which are configured with corresponding abutment surfaces 122 and 132 , are inserted into a pressing tool 200 that generates the connecting node 160 as shown in FIG. 5 a . Correspondingly configuring the two-part pressing tool 200 makes it possible to also realize different connecting angles than the shown 180° connecting angle. The pressing tool 200 is configured to enable accurately fixing the profile ends 121 and 131 in position. The abutment surfaces 122 and 132 of the profile ends 121 and 131 to be connected are spaced apart by a homogenous or uniform gap S. The size of the gap or the gap width B is for example 0.25 mm to 3 mm and in particular 0.5 mm to 2.0 mm.
[0043] In the tool cavity 230 of the lower tool 210 a short-fiber-containing plastic mass K is present which was introduced already prior to inserting and positioning the profile ends 121 and 131 . The plastic mass K is preferably a thermoset mass (resin). After the positioning of the profile ends 121 and 131 that are to be connected additional short-fiber-containing plastic mass K is applied or sprayed onto the connecting region, for example with the shown spray device 300 .
[0044] Subsequently the pressing tool 200 is closed by lowering the upper tool 220 as shown in FIG. 5 b and a pressing process is performed. During this pressing process the defined amount of fiber-containing plastic mass K is distributed in the cavity 230 , wherein the profile ends 121 and 131 of the hollow profile components 120 and 130 arranged in the cavity 230 are surrounded form fittingly and wherein the fiber-containing plastic mass K is also pressed into the gap S. Hereby also a materially bonding connection between the plastic mass K, which forms the connecting nodes 160 , and the profile ends 121 and 131 is formed. The shape of the connecting node 160 is defined by the negative form of the tool cavity 230 .
[0045] During the pressing process the closing elements 125 and 135 act as barriers and prevent the fiber-containing plastic mass K from entering the profile chambers of the hollow profile components 120 and 130 . This also allows establishing a high defined forming pressure in the tool cavity 230 .
[0046] During production of the connecting node 160 only the profile ends 121 and 131 that are to be connected are inserted into the pressing tool 200 , so that the hollow profile components 120 and 130 protrude into the tool cavity 230 through openings in the pressing tool 200 . The pressing tool 200 is configured so as to enable accurately fixing the profile ends 121 and 131 in position. During the pressing process the sealing of the pressing tool 200 is accomplished by way of sealings 241 and 242 . The pressure-resistant closing elements 125 and 135 can stabilize the hollow profile walls in the sealing region and improve the sealing of the cavity.
[0047] After the preferably thermoset plastic mass K is cured as a result of pressure and temperature the pressing tool 200 can be opened and the produced node structure 110 can be removed as shown in FIG. 5 c . The connecting node 160 can have wall thicknesses in the range from 1 mm to 15 mm, wherein the same but also different wall thicknesses can be provided. The closing elements 125 and 135 improve the strength, stiffness and crash stability of the node structure without noticeably adding weight.
[0048] The short-fiber-containing plastic mass K can be pre-mixed and can be introduced into the tool cavity 230 prior to closing the pressing tool 200 , for example by means of the spray device 300 or the like. Furthermore a layered introduction is possible, wherein alternately fiber layers and plastic layers (resin layers) can be introduced. The short-fiber plastic mass K can also be introduced into the tool cavity 230 by injection after closing the pressing tool 200 (injection molding). | A method for producing a node structure includes providing at least two pre-manufactured profile components having respective profile ends provided with corresponding abutment surfaces; positioning the profile ends in a pressing tool so that a homogenous gap is formed between the abutment surfaces; performing a pressing process in the presence of a fiber-containing plastic mass in the pressing tool for generating a connecting node that form fittingly connects the profile ends, wherein the fiber containing plastic mass also enters into the gap. | 1 |
CROSS-REFERENCE TO RELATED APPLICATION
This application is a continuation of copending International Application No. PCT/EP01/07169, filed Jun. 25, 2001, which designated the United States and was not published in English.
BACKGROUND OF THE INVENTION
FIELD OF THE INVENTION
The present invention relates to a sealing sleeve for sealing joints in household appliances, especially, the joints between the outer drum and the front wall of the housing or the upper part of the suds container and the top frame in washing machines, which sealing sleeve can be secured by a substantially annular clamping element.
In washing machines or laundry dryers, it is important to ensure a suitable seal between the outer drum and the front wall of the housing in front-loading machines and between the upper part of the suds container and the top frame in top-loading appliances. Customarily, sealing sleeves are used for such a purpose and can be secured by conventional clamping elements or clamp/screw elements placed around the sleeve. German Published, Non-Prosecuted Patent Application DE 2 403 705 discloses a sealing sleeve that forms a sealing joint between the suds container of a washing machine, in which the laundry drum is mounted, and the housing wall or the loading door. In this configuration, the sealing sleeve is secured on the suds container pressed against the outer surface of the wall of the suds container by an annular retaining or securing spring.
A disadvantage of this conventional sealing sleeve is that a high degree of effort must be expended to secure the sealing sleeve and due to the fact that the clamping elements have to be attached from the outside and are visible means that no freedom of design is possible with respect to the connection geometry.
SUMMARY OF THE INVENTION
It is accordingly an object of the invention to provide a sealing sleeve for sealing joints in a household appliance that overcomes the hereinafore-mentioned disadvantages of the heretofore-known devices of this general type and that avoids the above disadvantages, so that, in addition to an improved visual appearance, the assembly effort is reduced and the shape of the sections of sealing sleeve to be secured is capable of extremely wide variations in design.
With the foregoing and other objects in view, in a household appliance having an outer drum, a housing with a front wall, joints between the outer drum and the front wall, a suds container with an upper part, a top frame, and joints between the upper part and the top frame, there is provided, in accordance with the invention, a sealing sleeve for sealing at least one of the joints including a section to be secured in the appliance, the section having an interior and a substantially annular clamping element being molded into the interior, securing the section in the appliance, and sealing at least one of the joints.
According to the invention, the clamping element is molded into the interior of the section of the sleeve to be secured. As a result, the on-site assembly effort is substantially reduced and the shape of the sealing sleeve is capable of extremely wide variations in design. Advantageously, moreover, the clamping element is not visible from the outside.
In accordance with another feature of the invention, the section has an outer surface and an annular channel with at least one groove and the channel is connected by the at least one groove to the outer surface of the sealing sleeve and receives the clamping element. Advantageously, the sealing sleeve includes, in its interior, an annular channel, which is connected by at least one groove to the outer surface of the sealing sleeve. Such a configuration ensures that the clamping element is retained firmly and securely in the sealing sleeve but, nevertheless, external access to the clamping element is possible at all times.
Particularly advantageously, in accordance with a further feature of the invention, the clamping element can be pre-mounted in the sealing sleeve before the sealing sleeve is mounted in the household appliance. As a result, the assembly effort when the sealing sleeve is inserted can be still further reduced.
To simplify the production operation, in accordance with an added feature of the invention, it is additionally advantageous to form the sealing sleeve by injection molding.
In accordance with an additional feature of the invention, the clamping element is elastic.
In accordance with yet another feature of the invention, the clamping element is automatically capable of elastic further tensioning.
In accordance with yet a further feature of the invention, the clamping element is a helical spring.
In accordance with yet an added feature of the invention, the clamping element is a helical spring.
The effort of pre-mounting the clamping element in the sealing sleeve is advantageously eliminated if the sleeve already contains the clamping element during injection molding.
In accordance with yet an additional feature of the invention, the clamping element is jointly injected around the sleeve when the sleeve is injection-molded.
In accordance with again another feature of the invention, the clamping element is jointly injected molded with the section.
In accordance with again a further feature of the invention, a front housing wall of the appliance limits a door aperture and has an edge with a curved, substantially annular collar and the section is a beading and, with the clamping element, is adapted to engage with the annular collar.
If a beading of the sealing sleeve is so configured that it comes into engagement with a curved, substantially annular edge region of the end of the front housing wall limiting the door aperture, then a sealing sleeve excellently matched to the washing machine components used hitherto is, advantageously, provided.
With the objects of the invention in view, there is also provided a sealing section for a household appliance, including a body having an interior and a substantially annular clamping element being molded into the interior, the clamping element adapted to secure the section in the appliance and to seal at least one of a joint between an outer drum and a front wall of a housing of the appliance and a joint between an upper part of a suds container and a top frame of the appliance.
With the objects of the invention in view, in a washing machine having an outer drum, a housing with a front wall, joints between the outer drum and the front wall, a suds container with an upper part, a top frame, and joints between the upper part and the top frame, there is also provided a sealing sleeve for sealing at least one of the joints including a section to be secured in the washing machine, the section having an interior and a substantially annular clamping element being molded into the interior, securing the section in the appliance, and sealing at least one of the joints.
With the objects of the invention in view, there is also provided a washing machine, including an outer drum, a housing with a front wall, joints between the outer drum and the front wall, a suds container with an upper part, a top frame, joints between the upper part and the top frame, and a sealing sleeve for sealing at least one of the joints, the sealing sleeve having a section having an interior and a substantially annular clamping element being molded into the interior, securing the section in the appliance, and sealing at least one of the joints.
Other features that are considered as characteristic for the invention are set forth in the appended claims.
Although the invention is illustrated and described herein as embodied in a sealing sleeve for sealing joints in a household appliance, it is, nevertheless, not intended to be limited to the details shown because various modifications and structural changes may be made therein without departing from the spirit of the invention and within the scope and range of equivalents of the claims.
The construction and method of operation of the invention, however, together with additional objects and advantages thereof, will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a fragmentary, vertical cross-sectional view through a door region of a front-loading washing machine according to the invention;
FIG. 2 is an enlarged, fragmentary, cross-sectional view of the encircled detail in FIG. 1 of a first embodiment of the securing region of the sealing sleeve according to the invention; and
FIG. 3 is an enlarged, fragmentary, cross-sectional view of the encircled detail II in FIG. 1 of a second embodiment of the securing region of the sealing sleeve according to the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring now to the figures of the drawings in detail and first, particularly to FIG. 1 thereof, there is shown a cross-sectional view of a door region of a front-loading washing machine with a bull's-eye-type door 1 having a pot-shaped glass window 2 , which is fixed in a frame 3 . In the closed position of the door, sealing lips 4 and 5 lie on the inside of the edge region of the door 1 and prevent escape to the exterior of water from the interior space of the washing machine located to the right of the door.
The door 1 is fixed through a non-illustrated hinge on a window cutout of a housing 6 of the washing machine containing a pre-rolled sheet metal collar 8 in an edge region 7 of the window. The outer beading 9 of a sleeve 10 is buttoned onto the sheet metal collar 8 . A clamping element 11 , for example, an annular helical spring, set into the beading 9 clamps the beading 9 against the neck of the sheet metal collar 8 .
FIGS. 2 and 3 show, in an enlarged cross-sectional view, the beading 9 of the sealing sleeve 10 , which includes an annular channel 12 in its interior. The channel 12 is connected to the outer surface of the beading 9 of the sealing sleeve 10 through one groove 13 in FIG. 2 and through two grooves 13 and 14 disposed perpendicular to one another in FIG. 3. A substantially annular clamping element 11 is molded into the annular channel 12 . A recess having approximately the shape of a quarter circle is molded into the beading 9 of the sealing sleeve 10 , into which recess a rolled-up, substantially annular collar 8 of the edge of the front section of the housing wall 7 limiting the door aperture is introduced.
In the embodiment according to FIG. 3, in which the window edge region 7 of the front housing wall 6 has only a narrow, seamed-in edge, it is advisable to cover such an edge region with another annular lip 16 covering the edge region 7 .
The sealing sleeve 10 is customarily produced by the injection molding process. In such a process, a corresponding mold is constructed and filled by injection under high pressure with a liquid and elastic material (for example, rubber), which later cures to become softly elastic. As a result, the sealing sleeve 10 can be formed in a predetermined shape with very detailed accuracy.
In principle, there are two possible ways of molding the clamping element 11 into the interior of the sealing sleeve 10 . First, the mold can be equipped with a corresponding core for the subsequent channel 12 and at least one groove 13 or 14 . Then, after curing of the injection molding material, it is possible to introduce the clamping element 11 through the groove 13 or 14 into the annular channel 12 in the interior of the beading 9 of the sealing sleeve 10 .
Alternatively, the annular clamping element 11 can also be previously secured in the injection mold through an annular, continuous rib or through webs attached at individual points in the annular mold. During the subsequent injection molding, in such a case, the clamping element 11 is injected around the sealing sleeve 10 so that the clamping element 11 and the sealing sleeve 10 form a single component and it is no longer necessary to introduce the clamping element 11 into the channel 12 . When individual webs are used, the beading 9 of the sealing sleeve 10 includes, after the injection molding, not a continuous groove 13 for connecting the channel 12 to the outside of the sealing sleeve 10 but a plurality of individual passage apertures corresponding to the shape of the retaining webs.
The use of a plurality of circular ribs in the injection mold serves to provide better retention of the clamping element 11 . In such a case, after injection molding, a corresponding plurality of annular grooves 13 and 14 are formed in the beading 9 of the sealing sleeve 10 .
In principle, any annular structure capable of automatic elastic further tensioning can be used as the clamping element 11 , such as, for example, a tensioning cable or a rubber band of relatively high tensile force. Particularly preferred, however, is the use of a helical spring, also known as a “worm spring,” as this retains its spring force even after a long period of operation and, thus, guarantees reliable sealing. It should be noted that, when injection takes place directly around a helical spring, the latter must previously be provided with a suitable sheathing, as, otherwise, material of the sleeve 10 penetrates between the individual coils of the spring during injection molding, which may result in a reduction of the spring force or even a complete elimination of the spring force.
In the above-mentioned embodiments, which are adapted to the customary embodiments of the curved, substantially annular collar 8 of the edge section 7 of the front housing wall 6 limiting the door aperture, the beading 9 , with the clamping element 11 jointly injected around it during injection molding or pre-mounted in the channel 12 after injection molding, is merely inverted with its recess in the shape of a quarter circle over the correspondingly shaped collar 8 . As a result of the spring force of the clamping element 11 , the beading 9 of the sealing sleeve 10 is, then, permanently pressed against the collar 8 , so that slipping of the sealing sleeve 10 is prevented.
The invention is not, however, confined to the embodiments described herein but includes all conceivable geometrical shapes, ranging from the simple rectangle to complexly configured beadings. The section of the sealing sleeve to be secured merely needs to be sufficiently thick to receive the clamping element in its interior. Thus, the subject of the present invention can be used in virtually any field in which sealing sleeves are employed. | A sealing sleeve seals joints in household appliances, especially the joints between the suds container and the front wall of the housing or the upper part of the suds container and the top frame in washing machines, and can be secured to the appliance by a substantially annular clamping element. The clamping element can be molded into the interior of the section (which can be a beading) of the sealing sleeve to be secured. | 3 |
RELATED APPLICATION(S)
This application is a Continuation Application of U.S. patent application Ser. No. 08/335,538 filed Nov. 7, 1994, now U.S. Pat. No. 5,881,313, the entire teachings of which are incorporated herein by reference.
FIELD OF THE INVENTION
This invention relates generally to computer systems and arbitration for a shared data transfer resource, and specifically to transfer of data between a host memory and a network adapter through a shared bus.
BACKGROUND
In computer networks, network adapters are used to connect host computer systems to external computer networks. A network adapter is typically coupled with the host computer system through a shared data transfer resource, such as a peripheral bus or system bus. Also normally accessible through the shared bus is a host memory, in which data structures that are shared between the adapter and the host computer system are stored. The host memory typically contains data in the form of cells or packets that are to be transferred to the network adapter and subsequently transmitted onto the computer network. Further, the host memory is used to store cells and packets written by the network adapter after the cells and packets are received from the computer network.
The shared bus that is used to couple the network adapter with the host computer system is shared among multiple competing processes within the network adapter. These processes must be granted access to the shared bus in a manner that is fair and which guarantees minimal service levels negotiated for virtual circuits created by the host computer system through the network adapter. Access to the bus by requesters within the network adapter is effectuated by granting access to a set of logic that operates the bus for the network adapter, such as a Direct Memory Access (DMA) logic.
For example, in computer networking technologies such as Asynchronous Transfer Mode (ATM), virtual circuits are established having several negotiated performance parameters. These performance parameters are known as Quality of Service (QoS) parameters. Quality of Service parameters include average throughput, peak throughput, and latency tolerance. In order that the level of performance guaranteed by the QoS parameters not be compromised, access to any shared resources must be allocated among multiple requesters associated with multiple virtual circuits in accordance with the negotiated quality of service parameters for each virtual circuit. This problem is exacerbated by the large number of virtual circuits permitted in computer network technologies such as ATM.
In an alternative example of modern networking technology, there is also the concept of “flows” for a negotiated service level. In such systems, the service level may be defined on a packet by packet basis, without necessarily setting up virtual circuits, and without creating cells from packets. In this type of system, access to the shared resource must be allocated such that the negotiated service level is similarly maintained, albeit on a packet by packet basis.
A further problem exists in communication of status information from the network adapter to the host computer system. Such information is often passed through the same shared bus resource over which packet or cell data is passed. If this information is not communicated in a timely manner between the network adapter and the host computer system, any efficiencies in moving data between the host and the network adapter will be negated. It is therefore further required that the shared bus be used to communicate status information in a manner that does not adversely effect the transmit or receive performance of the network adapter.
In existing systems, there are a relatively small number of requesters. For example, in a system having only one transmit queue and one receive queue in the host, there can be only a proportionally small number of competing requests for any shared data transfer resource, since the processing within each of the two queues is typically sequential. However, when a large number of independent transmit and receive queues are used, many concurrent requests for access to the shared data transfer resource may be simultaneously present. These multiple concurrent requests must be processed correctly, and with consideration of the relative priority or negotiated service level of each request.
The contents of transmit and receive queues in host memory are generally some number of descriptors, each descriptor identifying an area of host memory in which data is or may be stored. In existing systems, the networking adapter has obtained decriptors and data from the host in a strictly sequential fashion. For example on transmit, the adapter first reads one or more descriptors, followed by the data indicated by those descriptors. When multiple independent queues are used, it is desirable to interleave different types of requests from different data flows, such as requests to move descriptors from a first host queue and requests to move data indicated by descriptors already fetched from a second host queue.
Also in systems using multiple transmit queues within the host computer system, it is impracticable to use a large FIFO in the adapter to store data for each transmit queue. Therefore a system of arbitrating for requests to move data from the multiple transmit queues into the FIFOs within the adapter must efficiently allocate access to any shared data transfer resource. Otherwise a FIFO may be underrun, potentially resulting in the QoS parameters for a connection being violated. This problem is particularly difficult because the future availability of the shared resource may be difficult to predict. Each request for the shared data transfer resource must therefore be processed in a way that avoids underrunning any of the FIFOs such that they do not become empty.
In addition to the above design issues there is also a well known problem of maintaining fairness between transmit and receive operations. Thus it is required that neither transmit nor receive data be given excessive priority over the other.
It is therefore desirable to have a new system for arbitrating between multiple requesters for a shared resource such as a peripheral bus. The new system should be tailored to meet the needs of a network adapter for networking technologies such as ATM. Such a new system should also provide support for Quality of Service requirements of a multiple virtual circuit system such as ATM. And further the system should provide service for a large number of potential requesters. An acceptable degree of fairness must be guaranteed between transmit and receive operations. And the new design should be flexible enough so that parameters may be adjusted to control the eventual service provided to different parts of the system in the network adapter so that fairness is perceived by the eventual users of the network.
SUMMARY
In accordance with principles of the invention, there is provided an arbitration system for multiple requesters of a shared data transfer resource, such as a system bus or a peripheral bus. The disclosed system arbitrates among a large number of request classes which are divided into multiple levels of a request hierarchy. In the example embodiment, the multiple requesters include logic for processing received data from the network, logic for processing data to be transmitted onto the network, logic for moving transmit and receive descriptors between the host memory and the adapter, logic for reporting non-error and maintenance status information from the adapter to the host, and logic for generating error and maintenance status information from the adapter to the host.
In the disclosed embodiment, non-error and maintenance status updates provide information to the host memory such as consumer pointers within the adapter. Error and maintenance status updates provide information to the host memory such as the value of error counters.
The new system ensures fairness between transmit and receive processes, that FIFOs associated with transmit queues are not underrun, and further that notifications of non-error and maintenance status information are processed quickly. Also, latency of delivering received data to the host is minimized.
In a disclosed example embodiment, there is described a system for arbitrating between multiple requests for a shared resource. The requests are divided into request classes. The example system includes a logic process for determining a relative priority of each request in a first request class. The first request class consists of requests to move data from host memory into an adapter for transmission onto a network. The example further includes a logic process for determining a high or a low priority of each request in a second request class. The second request class consists of requests to move transmit queue descriptors from a host memory into the adapter. A logic process is further provided to select one request from the first request class having a highest relative priority.
The example embodiment also includes a logic process for selecting a request from the second request class having a high priority. The second request class consists of requests to move descriptors from the host into the network adapter. An arbitration process is then used to choose between the request selected from the first request class and the request selected from the second request class. The arbitration process is based on a 1 of N round robin arbitration, and selects a request from the second request class once every N times the shared resource is available, where N is a predetermined integer.
The disclosed system also provides for processing of requests associated with reading of descriptors from a relatively large number of receive queues in host memory, as well as requests to move data from the network adapter into areas in host memory indicated by those descriptors read from the receive queues. Moreover, the system processes requests for the shared resource to write non-error and maintenance status information into the host memory, as well as requests to write error and maintenance information. The system allows non-error and maintenance status information such as updated consumer pointers to be written to the host with minimal latency. In addition, error and maintenance status information, such as performance counters and indication of non-fatal errors, is piggy-backed onto non-error and maintenance status information. Thus whenever a non-error and maintenance status update request is granted, any current error and maintenance information is also written into the host memory. Further, non-error and maintenance status update requests are allowed independent access to the shared resource at a relatively low priority.
The system handles all of these requests in such a way that the shared resource is allocated consistent with quality of service parameters for existing virtual circuits, and latency is minimized in providing service to requests to write non-error and maintenance status information into the host memory.
These and other features of the present invention will become apparent from a reading of the detailed description in conjunction with the attached drawings in which like reference numerals refer to like elements in several views.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a diagram of a network node having a network adapter;
FIG. 2 is a detailed diagram of the elements in an example embodiment of the network adapter shown in FIG. 1;
FIG. 3 is a detailed drawing of the elements in an example embodiment of the host memory as shown in FIG. 1;
FIG. 4 is a diagram of an example embodiment of a three stage arbitration system;
FIG. 5 is a flow chart describing an example embodiment of grant processing in the three stages of arbitration as shown in FIG. 4;
FIG. 6 is a detailed drawing of the elements in an example embodiment of grant processing logic in the first stage of arbitration as shown in FIG. 4;
FIG. 7 is a detailed drawing of the elements in an example embodiment of grant processing logic in the second stage of arbitration as shown in FIG. 4;
FIG. 8 is a detailed drawing of an example embodiment of grant processing logic in the third stage of arbitration as shown in FIG. 4;
FIG. 9 is a drawing of an example embodiment of a priority vector generated during grant processing by stage one of the arbitration as shown in FIG. 4;
FIG. 10 is a drawing of an example embodiment of request processing logic within stage one of the arbitration as shown in FIG. 4 for processing transmit data requests;
FIG. 11 is a drawing of an example embodiment of request processing logic in stage one of the arbitration as shown in FIG. 4 for processing receive data requests;
FIG. 12 is a drawing of an example embodiment of request processing logic in stage one of the arbitration as shown in FIG. 4 for processing receive descriptor requests;
FIG. 13 is a drawing of an example embodiment of request processing logic in the second stage of the arbitration shown in FIG. 4 for processing transmit data and transmit descriptor requests;
FIG. 14 is a drawing of an example embodiment of request processing logic in the second arbitration stage for processing receive data requests; and
FIG. 15 is a drawing of an example embodiment of request processing logic in the third arbitration stage.
DETAILED DESCRIPTION
FIG. 1 shows a Network Node 100 having a Host Memory 110 and a Host CPU 120 coupled with a Host Bus 125 . The Host Bus 125 is coupled with a Bus Bridge 130 , which in turn is coupled with an I/O Bus 115 . The I/O Bus 115 is coupled with a Network Adapter (Adapter) 105 , which in turn is coupled with a Network 126 .
During operation of the elements in FIG. 1, the Adapter 105 moves data between the Network 126 and the Host Memory 110 via the I/O Bus 115 . For purposes of example the Network 126 may be an Asynchronous Transfer Mode network, or other, such as Ethernet, FDDI, or Token Ring.
FIG. 2 is a detailed drawing of an example embodiment of the Adapter 105 as shown in FIG. 1 . FIG. 2 shows an Adapter 200 having a State Memory 210 coupled with a Control Logic 215 , a Network Interface 205 , and a Reassembly Memory 211 . The Network Interface 205 is further coupled with a network, for example, the Network 126 as shown in FIG. 1 . The State Memory 210 is further coupled with a Control Logic 215 . The Control Logic 215 . is further coupled with the Network Interface 205 , a DMA Arbiter 220 , the Reassembly Memory 211 and a DMA 225 . The DMA 225 is a Direct Memory Access logic, and is also coupled with the DMA Arbiter 220 and a bus, for example the I/O Bus 115 as shown in FIG. 1 .
In an example embodiment, the elements of FIG. 2, such as the DMA 225 , the DMA Arbiter 220 , Control Logic 215 and Network Interface 205 may be implemented in a combination of Application Specific Integrated Circuits (ASICs), discrete logic elements, and/or software or firmware processes executing on a microprocessor within the adapter 200 . For example, the elements 225 , 220 , 215 and 210 may be implemented in a single ASIC. An example of the bus coupled with the DMA 225 is the Peripheral Components Interconnect (PCI) bus.
The State Memory 210 is shown including 32 Transmit FIFOs 230 , 8 Receive Queues 235 , a set of Transmit Descriptors 240 and a set of Receive Descriptors 245 . The Transmit Descriptors 240 are associated with the 32 Transmit FIFOs 230 . Similarly, the Receive Descriptors 245 are associated with the 8 Receive Queues 235 . The 8 Receive Queues 235 contain descriptors indicating packets that have been reassembled in the Reassembly Memory 211 . Each received packet is first reassembled from cells received from the network through Network Interface 205 , and then an entry indicating the completely reassembled packet is placed on one of the Receive Queues 235 .
In an example embodiment, the Transmit Descriptors 240 are organized and referred to as a Transmit Descriptor Array (TDA). The TDA includes one entry for each of the 32 Transmit FIFOs 230 . Each entry in the TDA contains two descriptors, each descriptor containing addressing information regarding a data segment in Host Memory 110 as shown in FIG. 1 .
Further in the example embodiment, the Receive Descriptors 245 are organized and referred to as a Receive Descriptor Array (RDA), having one entry for each of the 8 Receive Queues 235 . Each entry in the Receive Descriptor Array entry contains 4 descriptors, each descriptor containing addressing information regarding a free space buffer in Host Memory 110 .
During operation of the elements shown in FIG. 2, the 32 Transmit FIFOs 230 store data transferred from a host memory, for example Host Memory 110 as shown in FIG. 1 . The data stored in the Transmit FIFOs 230 is subsequently transmitted in a ‘first in first out basis’ onto the network via the Network Interface 205 . The Receive Queues 235 are used to store descriptors indicating reassembled packets in the Reassembly Memory 211 . Subsequently, the data in the Reassembly Memory 211 indicated by the entries on the Receive Queues 235 is transferred to the host memory.
The specific locations of host memory into which received data is written by the adapter and from which data to be transmitted is read by the adapter are indicated by receive descriptors 245 and transmit descriptors 240 respectively. During operation, the adapter reads transmit descriptors from transmit queues in host memory, and receive descriptors from receive queues (see FIG. 3 ). Descriptors are read from host memory as they are needed by the adapter. No progress can be made in moving data to or from the network adapter unless the necessary descriptors have first been read from the host memory.
Further during operation of the elements shown in FIG. 1, the DMA Arbiter Logic 220 controls access to the DMA 225 by arbitrating among requests for the DMA 225 issued from the Control Logic 215 . The Control Logic 215 is the originator of multiple requests of different types. Examples of requests from the Control Logic 215 are requests to transfer data indicated by the Receive Queues 235 into Host Memory 110 (Receive Data Requests), requests to transfer data from the Host Memory 110 into the Transmit FIFOs 230 (Transmit Data Requests), requests to read a new descriptor from the Host Memory 110 into the TDA 240 (Transmit Descriptor Requests), requests to read a new descriptor from the Host Memory 110 into the RDA 245 (Receive Descriptor Requests), requests to write non-error and maintenance status information to the Host Memory 110 relating to completion of a transmission by the adapter (Transmit Status Requests), requests to write non-error and maintenance status information to the Host Memory 110 relating to receipt of data by the adapter (Receive Status Requests), and/or requests to write error and maintenance status information to the host memory (Error and Maintenance Requests). Each of the previously listed request types requires use of the DMA logic 225 to be completed.
When the I/O Bus 115 becomes available for the DMA 225 to use, the DMA Arbiter logic 220 indicates to the Control Logic 215 which requester will be allowed to use the DMA Arbiter logic 220 to transfer data to or from the host memory via the I/O Bus 115 .
FIG. 3 is a drawing of elements contained within an example embodiment of the Host Memory 110 as shown in FIG. 1 . FIG. 3 shows a Host Memory 300 including Transmit Queues 0-31 305 , Receive Queues 0-7 310 , a Status Block 325 , Free Space Buffers 315 , and Data Segments 320 . For purposes of example, there are 32 Transmit Queues. Further, for purposes of example, there are 8 Receive Queues. Each of the Transmit Queues 305 is associated with one of the 32 Transmit FIFOs 230 as shown in FIG. 2 . Further, each of the 8 Receive Queues 310 is associated with one of the 8 Receive Queues 235 as shown in FIG. 2 . Similarly, each of the Transmit Queues 305 is associated with an entry in the TDA 240 , and each of the Receive Queues 310 is associated with an entry in the RDA 245 .
Each of the 32 Transmit Queues 305 contains zero or more entries known as transmit descriptors. During operation of the adapter 200 as shown in FIG. 2, data is transferred between the Host Memory 300 and the Network 125 . Each transmit descriptor indicates a data segment within Data Segments 320 having data which is to be transmitted onto the network.
The Adapter 200 moves transmit descriptors from the 32 Transmit Queues 305 into the TDA 240 as space becomes available in the TDA 240 . Space becomes available in the TDA 240 when the adapter has transmitted all of the data contained within a Data Segment indicated by a given Transmit Descriptor stored in an entry within the TDA 240 . Upon this occurrence, and when there is another transmit descriptor in the transmit queue within host memory (see element 305 in FIG. 3) associated with that entry in the TDA 240 , the control logic 215 in FIG. 1 issues a transmit descriptor request to the DMA Arbiter 220 . The DMA Arbiter subsequently grants the request, and the control logic then uses the DMA 225 to transfer the new transmit descriptor from host memory into the TDA 240 .
When an entry in the TDA 240 is non-empty, the control logic 215 issues a transmit data request to the DMA Arbiter 220 . Subsequently the DMA Arbiter 220 grants the request, and the control logic 215 then uses the DMA 225 to transfer data from a data segment indicated by a transmit descriptor contained in that entry in the TDA 240 . When all the data in a data segment indicated by a transmit descriptor in an entry in the TDA 240 has been transmitted or moved from the host memory 300 into a transmit FIFO within the adapter, that transmit descriptor is no longer useful, and the space within the entry in the TDA 240 becomes available to store another transmit descriptor.
Each of the 8 Receive Queues 310 includes zero or more entries known as receive descriptors. Each receive descriptor includes indication of a free space buffer within Free Space Buffers 315 , for storage of data received from the network. Each of the 8 Receive Queues 310 contains one or more entries known as receive descriptors. During operation of the adapter 200 as shown in FIG. 2, data is transferred between the Network 125 and the Host Memory 300 . Each receive descriptor indicates a free space buffer within Free Space Buffers 315 available to store data which is received from the network.
The Adapter 200 moves receive descriptors from the 8 Receive Queues 310 into the RDA 245 as space becomes available in the RDA 245 . Space becomes available in the RDA 245 when the adapter has finished using a Data Segment indicated by a given receive descriptor stored in an entry within the RDA 245 . Upon this occurrence, the control logic 215 in FIG. 1 issues a receive descriptor request to the DMA Arbiter 220 . The DMA Arbiter subsequently grants the request, and the control logic then uses the DMA 225 to transfer a new receive descriptor from host memory into the RDA 245 .
When an entry in the RDA 245 is non-empty, and a packet has been received and reassembled in the receive queue within the Reassembly Memory 211 associated with the entry, the control logic 215 issues a receive data request to the DMA Arbiter 220 . Subsequently the DMA Arbiter 220 grants the request, and the control logic 215 then uses the DMA 225 to transfer data indicated by an entry on one of the receive Queues 235 into one of Free Space Buffers 315 indicated by a receive descriptor contained in that entry in the RDA 245 . When all the data for a free space buffer indicated by a receive descriptor in the RDA 245 has been transferred from the Reassembly Memory into host memory, that receive descriptor has been consumed, and the space within the entry in the RDA 245 becomes available to store another receive descriptor.
The Status Block 325 includes pointers to entries in the Transmit Queues 305 and the Receive Queues 310 indicating the position of the consumer and the producer indices for each one of these queues. The host computer system produces buffers, and is therefore the producer, providing Data Segments and Free Space Buffers which are consumed by the adapter. The host computer system maintains a producer index for each queue in host memory. The adapter maintains its position in each of the queues in host memory with a consumer index. In order to synchronize the producer and consumer, the adapter writes its consumer index for each queue into the Status Block 325 in response to certain predetermined events. When the adapter desires to write a consumer index into the Status Block 325 , the Control Logic 215 generates either a transmit status request (if the consumer index is for one of the Transmit Queues 305 ), or a receive status request (if the consumer. index is for one of the Transmit Queues 305 ). Subsequently the DMA Arbiter 220 grants the request, and the Control Logic 215 uses the DMA 225 to write the consumer index into the Status Block 325 . Each time a transmit status request or receive status request is granted, the Control Logic 215 also writes any current error and maintenance information into the host memory. In this way, error and maintenance status updates are piggy-backed onto non-error and maintenance status updates.
FIG. 4 is a detailed drawing of an example embodiment of the DMA arbiter 220 as shown in FIG. 2 . FIG. 4 shows a three stage arbitration system for controlling access to a shared resource, for example DMA 225 . FIG. 4 shows a first stage of arbitration 400 , coupled with a second stage of arbitration 402 , which is further coupled with a third stage of arbitration 404 . In FIG. 4, “request processing” is indicated as proceeding from left to right, while “grant processing” is shown going from right to left.
The request processing inputs to stage one 400 are transmit data requests 0-31 406 , transmit descriptor requests 0-31 408 , receive data requests 0-7 410 , and receive descriptor requests 0-7 412 . For purposes of example, all requests are implemented as a binary logic signal that is asserted when a specific request is present, and unasserted when that request is not present. In the example embodiment of FIG. 4, a request by the Control Logic 215 to read data from a data segment indicated by a transmit descriptor within the TDA entry associated with transmit queue 0 causes assertion of transmit data request (0) within transmit data requests 0-31 406 . When the DMA Arbiter 220 subsequently grants that request, the Control Logic 215 uses the DMA 225 to transfer data from that data segment into the one of Transmit FIFOs 230 associated with transmit queue (0). Further, for example, a request by the Control Logic 215 to obtain a new descriptor from one of the host transmit queues would be indicated by assertion of one of the 32 possible transmit descriptor requests 408 .
Also for example, a request by the Control Logic 215 to write data to a free space buffer indicated by a receive descriptor within the RDA entry associated with Receive Queue 0 in host memory causes assertion of receive data request (0) within receive data requests 0-7 410 . When the DMA Arbiter 220 subsequently grants that request, the Control Logic 215 uses the DMA 225 to transfer data to that free space buffer from the Reassembly Memory indicated by an entry on the one of Receive Queues 235 associated with Receive Queue 0 in Host Memory.
Similarly for example, a request by the Control Logic 215 to obtain a new transmit or receive descriptor from one of the host transmit or receive queues is be indicated by assertion of the corresponding one of either the transmit descriptor requests 408 or receive descriptor requests 412 .
The request processing outputs from stage one of the arbitration 400 are transmit data high (Xmit_Data_H) 414 , transmit data low (Xmit_Data_L) 416 , transmit descriptor high (Xmit_Data_H) 418 , transmit descriptor low (Xmit_Desc_L) 420 . Further outputs from stage one of the arbitration 400 , include receive data high (Rcv_Data_H) 422 , receive data low (Rcv_Data_L) 424 , receive descriptor high (Rcv_Desc_H) 426 , and receive descriptor low (Rcv_Desc_L) 428 . The request processing outputs from stage one 400 of the arbitration are request processing inputs into stage two 402 of the arbitration.
Transmit data high 414 output from stage one 400 of the arbitration, indicates that a transmit data request was selected by arbitration stage 1 having a high priority. Similarly, transmit data low 416 output from stage one of the arbitration 400 indicates that a selected transmit data request is of low priority. Also, transmit descriptor high 418 output form stage one 400 of the arbitration indicates that a selected transmit descriptor request 408 is of high priority, and transmit descriptor low indicates that a selected transmit descriptor request 408 is of low priority. When transmit data high 414 is asserted, transmit data low 416 is not asserted. Also, when transmit descriptor high 418 is asserted, transmit descriptor low 420 is not asserted. Thus, a selected request will be of either high priority or low priority. The same mutually exclusive relationship holds true for receive data high 422 and receive data low 424 , as well as receive descriptor high 426 and receive descriptor low 428 . Specifically, if receive data high 422 is asserted, receive data low 424 is not asserted and vice versa. And finally, if receive descriptor high 426 is asserted then receive descriptor low 428 is not asserted and vice versa.
Stage 2 of the arbitration 402 further has two other request processing inputs, specifically Transmit Status (Xmit_Status) 430 , and Receive Status (Rcv_Status) 432 . The request signal Transmit Status 430 indicates a request by the Control Logic 215 for the DMA 225 to write non-error and maintenance status information into the Status Block 325 , for example the current value of a consumer index maintained by the adapter indicating the last entry processed by the adapter within one of the transmit queues 305 . The request signal Receive Status 430 indicates a request by the Control Logic 215 for the DMA 225 to write non-error and maintenance status information into the Status Block 325 , for example the current value of a consumer index maintained by the adapter indicating the last entry processed by the adapter within one of the receive queues 310 .
The request processing outputs from stage two 402 of the arbitration as shown in FIG. 4 are Transmit DMA High (Xmit_DMA_H) 434 , Transmit DMA Low (Xmit_DMA_L) 436 , Receive DMA High (Rcv_DMA_H) 438 , and Receive DMA Low (Rcv_DMA_L) 440 . These outputs from stage two of the arbitration 402 are multiply coupled with request processing inputs to stage three 404 of the arbitration as follows: Transmit DMA High 434 is coupled with input 442 and input 446 of stage three 404 . Transmit DMA Low 436 is coupled with input 450 and input 454 . Receive DMA High is coupled with input 452 and input 444 , and Receive DMA Low is coupled with input 456 and input 448 of stage three. As with the outputs of stage one 400 , the outputs of stage two 402 will indicate the mutually exclusive priority of selected inputs from stage 2 402 . Specifically, if Transmit DMA High 434 is true then Transmit DMA Low 436 is not true, and if Receive DMA High 438 is true then receive DMA Low 440 is not true and vice versa. Stage three of the arbitration 404 further includes an Error and Maintenance Status update Request (E_M_Request) input 470 , that is asserted when the Error and Maintenance Logic 471 (for example contained within Control Logic 215 as shown in FIG. 2) requests the DMA 225 to write error and maintenance information to the Status Block 325 in Host Memory 300 as shown in FIG. 3 . Example error and maintenance information is information regarding utilization of resources within the network adapter.
Stage three of the arbitration 404 is shown consisting of three logic blocks 405 , 466 , and 468 . Signals generated during request processing by stage three of the arbitration 404 are shown as: Transmit Request Present (Xmit) 458 , Receive Request Present (Rcv) 460 , Normal Request Present (Norm_Req) 462 , Normal Request Selected (Norm_Selected) 464 and Error and Maintenance Status Update Request Selected (E_M_Req_Sel) 467 .
The signal Normal Request Selected 464 is an input into AND gate 473 . The signal DMA Logic Available 469 is a further input into AND gate 473 . DMA Logic Available 469 , when asserted, indicates that the DMA 225 is available to service one of the requests passed to the DMA Arbiter 220 . The Grant Processing Trigger output 474 of AND gate 473 feeds back into logic block 405 , and triggers the “grant processing” (shown going from right to left in FIG. 4) logic of the elements shown in FIG. 4 .
DMA Logic Available 469 is also an input into AND gate 472 . A further input into AND gate 472 is Error and Maintenance Status Update Request Selected 467 . The output of AND gate 472 is Error and Maintenance Status Update Request Granted signal 499 fed back into Error and Maintenance Logic 471 . When the Error and Maintenance Logic 471 detects that Error and Maintenance Status Update Request Granted signal 499 is asserted, it then uses the DMA 225 to write error and maintenance information into the Status Block 325 as shown in FIG. 3 .
During request processing operation of the third stage of arbitration 404 , the signal Xmit 458 is asserted if either signal Xmit_DMA_H or the signal Xmit_DMA_L is asserted. Also, the signal Rcv 460 is asserted if either the signal Rcv_DMA_H or Rcv_DMA_L is asserted. The logic block 466 then asserts the signal Normal Request 462 if either the signal Xmit 458 or the signal Rcv 460 is asserted. The logic block 468 asserts the signal Error and Maintenance Status Update Request Selected 467 if the Error and Maintenance Status Update Request signal 470 is asserted and the Normal Request signal 462 is not asserted. If the Normal Request signal 462 is asserted, then the logic block 468 asserts the Non-Normal Request Selected signal 464 .
FIG. 5 is a flow chart showing an example embodiment of the grant processing operation of the three arbitration stages shown in FIG. 4 . The Grant Processing Trigger 516 is the same as Grant Processing Trigger output 474 in FIG. 4 . The flow of processing in FIG. 5 is from right to left.
In stage three 515 of the arbitration, as shown in FIG. 4, the DMA Arbiter 220 selects between transmit, receive, and error and maintenance status update requests. If an error and maintenance status update request is granted, that is indicated by Error and Maintenance Status Update Request Granted signal 518 . Error and Maintenance Status Update Request Granted signal 518 corresponds with Error and Maintenance Status Update Request Granted 499 in FIG. 4 . If an error and maintenance status update request is not granted, then stage 3 515 is followed by Stage 2 510 .
In Stage 2 510 the DMA Arbiter 220 selects between data, descriptor and non-error and maintenance status requests. If a non-error and maintenance status request is granted, that is indicated by Status Request Granted 520 . Status Request Granted 520 corresponds with Transmit Status Grant 482 and Receive Status Grant 481 shown in FIG. 4 . If a status request is not granted, then Stage 2 510 is followed by Stage 1 505 .
In Stage 1 505 , the DMA Arbiter 220 selects between individual transmit or receive data or descriptor requests. The output of grant processing in Stage 1 505 is a grant 500 of a specific request to one of the request inputs to Stage 1 of the arbitration 400 as shown in FIG. 4 . The grant 500 consists of the signals labeled 486 , 485 , 484 and 483 as shown in FIG. 4 .
FIG. 6 is a detailed drawing of the grant processing logic elements within an example embodiment of the Stage 1 of the arbitration 400 as shown in FIG. 4 as element 400 . The grant processing logic shown in FIG. 6 consists of four separate arbiters. The four arbiters are the Transmit Data Scheduler 600 for transmit data requests, the Transmit Descriptor Scheduler 602 for transmit descriptor requests, the Receive Data Scheduler 604 for receive data requests, and the Receive Descriptor Scheduler 606 for receive descriptor requests.
The Transmit Data Scheduler 600 is triggered by the signal Xmit Data Grant 615 , which corresponds with the signal Xmit_Data_Grant 477 as shown in FIG. 4 . The Transmit Data Scheduler 600 uses a combination of thresholding and dynamic priority to select one of the currently asserted transmit data requests 610 having the highest cumulative priority. The transmit data requests 610 in FIG. 6 consist of the transmit data requests 406 as shown in FIG. 4 .
During operation of the elements shown in FIG. 6, the Transmit Data Scheduler 600 accesses the Schedule Table 250 , and other data in the State Memory 210 , through the Control Logic 215 in order to create a Priority Vector, the format of which is shown in FIG. 9. A Priority Vector is created for each currently asserted Transmit Data Request. The Transmit Data Request having the Priority Vector with the highest value is selected by the Schedule Table Driven Scheduler, and then a corresponding grant signal in Xmit_Data_Request_Grant signals 0-31 614 is asserted. For purposes of example, the Xmit_Data_Request_Grant signals 0-31 are individual binary logic lines coupled with the Control Logic 215 . When Xmit_Data_Request_Grant signal 0 is asserted, that informs the Control Logic 215 that a transmit data request 0 has been granted by the DMA Arbiter 220 .
The Transmit Descriptor Scheduler 602 is triggered by the assertion of Xmit_Desc_Grant signal 633 . The logic block 618 determines the priorities of each one of transmit descriptor requests 0-31 620 . Transmit descriptor requests are issued when there is room for a new transmit descriptor to be stored in an entry within the TDA 240 as shown in FIG. 2. A transmit descriptor request is high priority when the FIFO corresponding with that request is below a predetermined level. Otherwise, the priority of a transmit descriptor request is low priority. The logic block 618 then sends the high priority transmit descriptor requests 624 to round robin arbiter 628 , and the low priority transmit descriptor requests 626 to the round robin arbiter 630 . If there are no high priority transmit descriptor requests, the signal 627 is asserted to the round robin arbiter 630 .
When the Xmit_Desc_Grant signal 633 is asserted, then the round robin arbiter 628 selects from those high priority transmit descriptor requests 624 on a round robin basis. The selected high priority transmit descriptor request is then granted access to the shared resource, which is indicated by asserting the corresponding one of Xmit_Desc_Req_Grant signals 632 , which correspond with Xmit_Desc_Req_Grant signals 0-31 483 in FIG. 4 .
When the Xmit_Desc_Grant signal 633 is present, and the signal 627 indicates that there are no high priority transmit descriptor requests, then round robin arbiter 630 selects from the low priority transmit descriptor requests on a round robin basis. The selected low priority transmit descriptor request is then indicated by asserting the corresponding one of Xmit_Desc_Req_Grant signals 632 , which correspond with Xmit_Desc_Req_Grant signals 0-31 in FIG. 4 .
The Receive Data Scheduler 604 consists of a Fixed Schedule Weighted Round Robin Arbiter 636 , having inputs of Receive Data Requests 0-7 638 , and triggered by Rcv_Data_Grant 643 . Receive Data Requests 0-7 638 correspond with Receive Data Requests 0-7 410 as shown in FIG. 4, and Rcv_Data_Grant 643 corresponds with Receive Data Grant 479 . The Arbiter 636 uses a weighted round-robin scheduling scheme. For example the following schedule is used to select between Receive Data Requests 0-7:
0 1 2 3 0 1 2 4 0 1 2 5 0 1 2 6 0 1 2 7 - - -
The above schedule weights arbitration in favor of Receive Data Requests 0, 1 and 2, as compared with Receive Data Requests 3, 4, 5, 6 and 7, by the ratio of 5:1. The selected one of Receive Data Requests 638 is then indicated by asserting the corresponding one of Receive Data Request Grant Signals 642 . The Receive Data Request Grant Signals 642 correspond with Receive Data Request Grant Signals 0-7 484 as shown in FIG. 4 .
The Receive Descriptor Scheduler 606 is triggered by the assertion of Rcv_Desc_Grant 647 , which corresponds with the Rcv_Desc_Grant signal 480 as shown in FIG. 4 . When the Rcv_Desc_Grant 647 is asserted, the Fixed Schedule Weighted Round Robin Arbiter 648 uses the same fixed schedule weighted round robin arbitration scheme as the Receive Data Scheduler 604 to select between those Receive Descriptor Requests 646 (corresponding with Receive Descriptor Requests 412 in FIG. 4) that are present. The selected one of Receive Descriptor Requests 646 is then indicated by asserting the corresponding one of Rcv_Desc_Req_Grant signals 0-7 649 , which correspond with the Rcv_Desc_Req_Grant 0-7 signals 483 as shown in FIG. 4 .
FIG. 7 is a drawing of an example embodiment of the grant processing logic in the second arbitration stage. Shown in FIG. 7 is a Transmit DMA Scheduler 700 . The Transmit DMA Scheduler 700 is shown having a Round Robin Arbiter 704 coupled with a 1 of N Round Robin Arbiter 706 . The 1 of N Round Robin Arbiter 706 is further coupled with a Logic Block 710 . Transmit DMA Scheduler 700 further includes Round Robin Arbiter 708 which is also coupled with the Logic Block 710 .
Inputs to the Round Robin Arbiter 704 are Transmit Data High signal 712 and Transmit Descriptor High signal 714 . A further input to the Round Robin Arbiter 704 is Transmit Grant signal 723 . The output of Round Robin Arbiter 704 is an input into the 1 of N Round Robin Arbiter 706 . A further input to the 1 of N Round Robin Arbiter 706 is a Transmit Status signal 716 . The output of the 1 of N Round Robin Arbiter 706 , is input into Logic Block 710 . Inputs into Round Robin Arbiter 708 are Transmit Data Low signal 718 , Transmit Descriptor Low signal 720 and Transmit Grant signal 723 . The output of Round Robin Arbiter 708 is input into the Logic Block 710 . The outputs of the Logic Block 710 are Transmit Data Grant signal 722 , Transmit Descriptor Grant 724 and Transmit Status grant 725 .
Logic is included in the Transmit DMA Scheduler 700 so that only one of the Round Robin Arbiters 704 or 708 is triggered each time a Transmit Grant signal 723 is provided. If neither the High or Low Signal for Data (Transmit DMA High 712 or Transmit DMA Low 718 ) are active, then for the purposes of triggering one of the Round Robin Arbiters 704 or 708 , the logic provided ensures that the appropriate Round Robin Arbiter is triggered based on the Transmit Descriptor High or Transmit Descriptor Low signal being active. Similar logic is used if both the Transmit Descriptor High and Transmit Descriptor Low signal are not asserted. An example of the logic for selecting a particular arbiter to be triggered is shown in FIG. 8 and is explained in greater detail below.
The Transmit DMA Scheduler 700 is for example contained within stage two of the arbitration logic 402 shown in FIG. 4 . Further, for example, the Transmit Data High signal 712 corresponds with Transmit Data High 414 as shown in FIG. 4 . The Transmit Descriptor High signal 714 corresponds with the Transmit Descriptor High signal 418 as shown in FIG. 4 . The Transmit Status signal 716 corresponds with the Transmit Status signal 430 as shown in FIG. 4 . Further, the Transmit Data Low signal 718 corresponds with the Transmit Data Low signal 416 in FIG. 4 and the Transmit Descriptor Low signal 720 corresponds with the Transmit Descriptor. Low signal 420 in FIG. 4 . The Transmit Grant signal 723 in FIG. 7 corresponds with the Transmit Grant signal 475 as shown in FIG. 4 . Also the Transmit Data Grant signal 722 corresponds with the Transmit Data Grant signal 477 in FIG. 4 and the Transmit Descriptor Grant signal 724 corresponds with the Transmit Descriptor Grant signal 478 in FIG. 4 . The Transmit Status Grant signal 725 in FIG. 7 corresponds with the Transmit Status Grant signal 482 as shown in FIG. 4 .
During operation of the elements shown in the transmit DMA Scheduler 700 of FIG. 7, the Round Robin Arbiter 704 and Round Robin arbiter 708 are triggered by the Transmit. Grant signal 723 . The Transmit grant signal 723 is received from the third stage of arbitration. Upon receipt of the Transmit Grant signal 723 the Round Robin Arbiter 704 selects between Transmit Data High 712 and Transmit Descriptor High 714 based on an evenly weighted round robin scheduling system. The selected one of Transmit Data High 712 or Transmit Descriptor High 714 is then passed to the 1 of N Round Robin Arbiter 706 , as well as the transmit status signal 716 .
The 1 of N Round Robin Arbiter 706 then selects between the output of Round Robin Arbiter 704 and Transmit Status signal 716 based on a heavily weighted one of N round robin arbiter system, in which the Transmit Status Signal 716 is selected once out of every 32 passes. The output of 1 of N Round Robin Arbiter 706 then passes to Logic Block 710 .
The input signals Transmit Data Low 718 and Transmit Descriptor low 720 feed into Round Robin Arbiter 708 during operation. Round Robin Arbiter 708 is triggered into operation by Transmit Grant signal 723 . Round Robin Arbiter 708 selects between Transmit Data Low signal 718 and Transmit Descriptor Low signal 720 on an evenly weighted round robin basis. The output of Round Robin Arbiter 708 feeds into the Logic Block 710 . The Logic Block 710 selects between the output from 1 of N Round Robin Arbiter 706 and the output from Round Robin Arbiter 708 .
The Logic Block 710 will select the high priority signal from 1 of N round Robin Arbiter 706 if it is present. If no high priority signal is present, the Logic Block 710 selects the signal from Round Robin Arbiter 708 . When the output from 1 of N Round Robin Arbiter 706 is Transmit Status signal 716 then the output from Logic Block 710 is the assertion of Transmit Status Grant signal 725 . If the output of 1 of N Round Robin Arbiter 706 is Transmit Data High 712 , then the Logic Block 710 will assert Transmit Data Grant 722 . If the output of 1 of N Round Robin Arbiter 706 is Transmit Descriptor High 714 , then the output of the Logic Block 710 will be equal to Transmit Descriptor Grant signal 724 .
If there is no output from 1 of N Round Robin Arbiter 706 into Logic Block 710 , then if the output of Round Robin Arbiter 708 is Transmit Data Low 718 , then the output of the Logic Block 710 is Transmit Data Grant 722 . Similarly, if there is no output from 1 of N Round Robin Arbiter 706 , and the output of Round Robin Arbiter 708 is Transmit Descriptor Low 720 , then the output of the Logic Block 710 is Transmit Descriptor Grant signal 724 .
Thus, it is shown that transmit DMA Scheduler 700 arbitrates simultaneously between transmit data, transmit descriptor, and transmit status requests upon receipt of the transmit grant signal 723 . The transmit DMA Scheduler 700 may be implemented for example using three round robin pointers, one each for the arbiters 704 , 706 and 708 . The disclosed system thereby implements a simple, round robin arbitration between both high and low priority transmit data and transmit descriptor requests. In this way, the low priority round robin pointer selects among low priority requests, and high priority pointer selects among high priority requests.
As described above, transmit status update requests have a single priority level. A 1 of N round robin arbiter is used to choose between a high priority data or descriptor request and a transmit status update request. For example, for every N high priority transmit data or transmit descriptor requests, a single transmit status update request will be selected. In the example embodiment, “N” is programmable to be between 1 and 255.
Further shown in FIG. 7 is Receive DMA Scheduler 702 . The Receive DMA Scheduler 702 is contained within the second arbitration stage 402 as shown in FIG. 4 . The Receive DMA Scheduler 702 is grant processing logic. The example embodiment of the Receive DMA Scheduler 702 shown in FIG. 7 includes Round Robin Arbiter 726 , coupled with 1 of N Round Robin Arbiter 728 , which is further coupled with Logic Block 732 . Also shown in Receive DMA Scheduler 702 is Round Robin Arbiter 730 which is also coupled with Logic Block 732 . The inputs to Round Robin Arbiter 726 are Receive Data High signal 734 and Receive Descriptor High signal 736 . The output of Round Robin Arbiter 726 feeds into 1 of N round Robin Arbiter 728 . A further input into 1 of N Round Robin Arbiter 728 is Receive Status signal 738 . The output of 1 of N Round Robin Arbiter 728 is input into the Logic Block 732 .
A similar logic is included to select between Round Robin Arbiters 726 and 730 so that only one of them is triggered each time a receive grant signal 729 is received as was described for the Xmit DMA Scheduler 700 . An example of this logic is shown in FIG. 8 and is explained in greater detail below.
The inputs into Round Robin Arbiter 730 are Receive Data Low signal 740 and Receive Descriptor Low signal 742 . The output of Round Robin Arbiter 730 is input into the Logic Block 732 . Both Round Robin Arbiter 726 and Round Robin Arbiter 730 are triggered by assertion of Receive Grant signal 729 . The outputs of Logic Block 732 are Receive Data Grant signal 734 , Receive Descriptor Grant signal 736 , and Receive Status Grant signal 735 .
The receive DMA Scheduler 702 is for purposes of example contained within stage 2 of the arbitration shown as element 402 in FIG. 4 . Receive Data High signal 734 corresponds with Receive Data High signal 422 in FIG. 4 . Receive Descriptor High signal 736 corresponds with Receive Descriptor High signal 426 . Receive Status signal 738 corresponds with Receive Status signal 432 in FIG. 4 . Receive Data Low signal 740 corresponds with Receive Data Low signal 424 . And Receive Descriptor Low signal 742 corresponds with Receive Descriptor Low signal 428 . Further, Receive Grant signal 729 corresponds with Receive Grant signal 476 , Receive Data Grant signal 734 corresponds with Receive Data Grant signal 479 and Receive Descriptor Grant signal 736 corresponds with Receive Descriptor Grant signal 480 . Finally, Receive Status Grant signal 735 corresponds with Receive Status Grant signal 481 in FIG. 4 .
During operation of the example embodiment of the Receive DMA Scheduler 702 shown in FIG. 7, the Round Robin Arbiter 706 selects on a round robin basis between the signals Receive Data High 734 and Receive Descriptor High 736 . The output of the Round Robin Arbiter 726 feeds into 1 of N Round Robin Arbiter 728 along with the Receive Status signal 738 . The 1 of N Round Robin Arbiter 728 applies a weighted round robin arbitration system to its inputs. The selected output then feeds into the Logic Block 732 . The Round Robin arbiter 730 applies a simple round robin arbitration system to the inputs Receive Data Low 740 and Receive Descriptor Low 742 .
The selected one of the inputs to Round Robin Arbiter 730 is then fed into the Logic Block 732 . The Logic Block 732 then selects one of its input signals based on whatever signal has a high priority. For example, if the output of 1 of N Round Robin Arbiter is Receive Status signal 738 , then the output of the Logic Block 732 is Receive Status grant signal 735 . Thus, Receive Status Grant 735 will be asserted whenever the output of 1 of N Round Robin Arbiter 728 is Receive Status signal 738 .
If the output of 1 of N Round Robin Arbiter 728 is Receive Data High signal 734 then the output of the Logic Block 732 is Receive Data Grant signal 734 . If the output of 1 of N Round Robin Arbiter 728 is Receive Descriptor High 736 , then the output of the Logic Block 732 is Receive Descriptor Grant signal 736 .
If there is no output from 1 of N Round Robin Arbiter 728 and there is output from Round Robin Arbiter 730 then the output of Round Robin Arbiter 730 will determine the output of the Logic Block 732 . For example, if the output of Round Robin Arbiter 730 is Receive Data Low signal 740 and there is no output from 1 of N Round Robin Arbiter 728 , then the output of Logic Block 732 is Receive Data Grant signal 734 . Similarly, if the output of Round Robin Arbiter 730 is Receive Descriptor Low signal 742 and there is no output from 1 of N Round Robin Arbiter 728 , then the output of Logic Block 732 is Receive Descriptor Grant signal 736 .
In this way the Receive DMA Scheduler 702 arbitrates between receive data, receive descriptor, and receive status update requests. It is identical in functionality to the transmit DMA Scheduler 700 . Note, however, that the Receive DMA Scheduler 702 and the Transmit DMA Scheduler 700 may have different values of N for the one of N arbitration between high priority data or descriptor requests and non-error and maintenance status update requests.
FIG. 8 is an example embodiment of the grant processing logic within the third arbitration stage. FIG. 8 shows a DMA Scheduler 800 , as for example would be contained within the stage three arbitration logic 404 as shown in FIG. 4 . The DMA Scheduler 800 as shown in FIG. 8, includes a Lightly Weighted Round Robin Arbiter 802 , a Weighted Round Robin Arbiter 804 , a Weighted Round Robin Arbiter 806 , and a Weighted Round Robin Arbiter 808 . The outputs from these four round robin arbiters are inputs into Logic Block 810 .
The triggering inputs to Lightly Weighted Round Robin Arbiter 802 are Receive DMA high signal 814 and Transmit DMA High signal 816 . The triggering inputs to Weighted Round Robin Arbiter 804 are the outputs of OR gate 854 and OR gate 860 . The inputs to OR gate 854 are Receive DMA Low signal 818 and the output of AND gate 852 . The inputs to AND gate 852 are Transmit DMA Low signal 820 and the inverted Receive DMA High signal 814 . The inputs to OR gate 860 are Transmit DMA Low signal 820 and the output of AND gate 858 . The inputs to AND gate 858 are Receive DMA Low signal 818 and the inverted Transmit DMA High signal 816 .
The triggering inputs to Weighted Round Robin Arbiter 806 are Receive DMA High signal 822 and the output of OR gate 826 . The inputs to OR gate 826 are the inversion of Transmit DMA High signal 816 , and Transmit DMA Low signal 824 . The triggering inputs to Weighted Round Robin Arbiter 808 are Transmit DMA signal 828 , and the output of OR gate 829 , which has as inputs the inversion of Receive DMA High signal 822 , and Receive DMA Low signal 818 . All of the round robin arbiters in the DMA Scheduler 800 are triggered by the Start Feedback Processing signal 833 , as well as both of their triggering input signals being asserted.
The triggering inputs for the four arbiters enable at most one of the arbiters at any one time. The inputs subject to the described arbitration within the arbiters are the signals RCV_DMA_H 814 and XMIT_DMA_H 816 for 802 , XMIT_DMA_L 820 and RCV_DMA_L 826 for 804 , RCV_DMA_H 822 and XMIT_DMA_L 824 for 806 , and RCV_DMA_L 818 and XMIT_DMA_H 828 for 808 .
The Receive DMA High signal 814 corresponds with the Receive DMA High signal 438 as shown in FIG. 4 . Similarly, the Transmit DMA High signal 816 corresponds with Transmit DMA High signal 434 , Receive DMA Low signal 818 corresponds with Receive DMA Low signal 440 , Transmit DMA Low 820 corresponds with Transmit DMA Low signal 436 , Receive DMA High signal 822 corresponds with Receive DMA High signal 438 . Also, Start Feedback Processing signal 833 corresponds with Grant Processing Trigger signal 474 as shown in FIG. 4 . The Receive Grant signal 834 corresponds with the Receive Grant signal 476 in FIG. 4 and the Transmit Grant signal 832 corresponds with the Transmit Grant signal 474 .
During operation of the elements shown in the example embodiment of DMA Scheduler 800 , each of the round robin arbiters 802 , 804 , 806 and 808 , is triggered by the Start Feedback Processing signal 833 and both corresponding input signals. The Lightly Weighted Round Robin Arbiter 802 selects between its input signals based on a round robin system, with the exception that every predetermined number of cycles, where the predetermined number equals L, one of the two input signals is forced to be successful. The number of cycles L is programmable. Each time Start Feedback Processing signal 833 is asserted and both RCV_DMA_H 814 and XMIT_DMA_H 816 are also asserted is one cycle for Lightly Weighted Round Robin Arbiter 802 . Which input signal is favored each L cycles is determined by the setting of a bit in a control register in the DMA Arbiter 220 as shown in FIG. 2 .
The Weighted Round Robin Arbiter 804 implements a one of M round robin scheduling scheme, favoring the input signal Received DMA low. The Weighted Round Robin Arbiter 804 allows the Receive DMA Low signal 818 to be output once each M cycles. Each time Start Feedback Processing signal 833 is asserted and both output of OR gate 854 and output of OR gate 860 are also asserted is one cycle for Weighted Round Robin Arbiter 804 . The value of M is programmable.
The Weighted Round Robin Arbiter 806 , implements a weighted round robin system where the input signal Receive DMA High 822 is favored. Each time Start Feedback Processing 833 is asserted, RCV_DMA_H and the output of OR gate 826 are all asserted is one cycle for Weighted Round Robin Arbiter 806 . The output of the OR gate 826 is selected once every I cycles.
The Weighted Round Robin Arbiter 808 , similarly favors Transmit DMA High input 828 , selecting the output of OR gate 829 once every J cycles. Each time Start Feedback Processing 833 , and both XMIT_DMA_H 828 and the output of OR gate 829 are all asserted is one cycle for Weighted Round Robin Arbiter 808 .
The outputs selected by the Round Robin Arbiters 802 , 804 , 806 and 808 , are fed into the Logic Block 810 . The Logic Block 810 select whichever signal has highest priority from its input signals. For example, if Receive DMA High 814 is input into Logic Block 810 then Receive Grant 834 is asserted. Alternatively, if Transmit DMA High 816 is input into Logic Block 810 , Transmit Grant Signal 832 is asserted.
The DMA Scheduler 800 thereby serves to arbitrate between transmit requests and receive requests. The DMA Scheduler 800 contains four completely independent arbiters. Whenever a received DMA request and/or a transmit DMA request are pending, only one of the four state machines becomes active, depending on the relative priority of the request. If only one process has a request pending, a low priority request from the remaining processes will be assumed for purposes of activating one of the round robin arbiters.
For example, a low priority receive request with no accompanying transmit request will activate the round robin arbiter corresponding to two low priority requests, in this example weighted round robin arbiter 804 . In the example embodiment the weighted round robin arbiters are programmable through registers, namely a register L, a register M, and registers I and J in the DMA Arbiter 220 as shown in FIG. 2 .
As described above, the Lightly Weighted Round Robin Arbiter 802 during operation services two simultaneous high priority requests, and implements a more granular round robin weighting algorithm which may favor either the transmit or the receive requests. In the example embodiment of the Lightly Weighted Round Robin Arbiter 802 , a single 4-bit weighting register L holds the desired weighting value. A single bit in a control register in Lightly Weighted Round Robin Arbiter 802 , indicates whether the weighing favors the transmit request or the receive requests. In this way the control logic may select whether the transmit path or the receive path is favored for high priority requests.
In the Lightly Weighted Round Robin Arbiter 802 , the 4-bit counter counts by one every two cycles and sticks at the value in the weighing register L. Non-weighted round robin arbitration takes place until the counter reaches the value in the weighing register L, at which point either of the receive or transmit request, is favored, depending on the state of the single bit in the control register. When back to back DMA cycles for the favored process take place as a result of the weighing, the counter is reset to 0. A weighing register value of 0 indicates that no weighing should take place. In this way, the Lightly Weighted Round Robin Arbiter 802 insures that when both transmit and receive requests are high priority, neither is starved, while also including means for providing unequal service for receive over transmit or vice versa.
FIG. 9 shows an example embodiment of a Priority Vector 900 generated during grant processing stage of stage one 400 as shown. in FIG. 4 . The example of Priority Vector 900 is shown including a TDA Valid field 905 , a TPM Space field 910 , a Below Threshold field 915 , a Priority field 920 , a Latency Predicted field 925 , and a Tokens Predicted field 930 .
The TDA Valid field 905 is set to true if there is a least one descriptor pointing to a segment with valid data in the TDA entry associated with the FIFO for this transmission request. The TPM Space field 910 is set to true if there is at least a predetermined minimum size worth of space left in the FIFO for this transmission request. The Below Threshold field 915 indicates when true that the FIFO for this transmission request is below a predetermined water mark value. The Priority field 920 contains the priority of the virtual circuit currently associated with the FIFO for this transmission.
The Latency Predicted field (also know as the CL Predicted field) 925 contains the predicted time elapsed since the last previous transmission on the virtual circuit currently associated with the FIFO for this transmission, at a future point in time either 4, 8, 16, or 32 cell times from the current time. Thus, the latency predicted field 925 is used to adjust for the time between when the calculation is made in stage one of the arbiter and the actual time subsequently when data is available for transmission. The Tokens Predicted field 930 contains the predicted number of sustained rate tokens which the virtual circuit currently associated with the FIFO will have accumulated 4, 8, 16, or 32 cell times from the current time. The specific number of cell times from the current time is programmable. The amount of time selected is dependant on the anticipated amount of time for a DMA request to be satisfied and for data to arrive at the head of a transmit FIFO.
The relative priority of two transmit requests is determined by comparison of the priority vectors for the two requests. Priority vectors are compared by the Transmit Data Scheduler 600 as shown in FIG. 6 to find the highest priority transmit data request currently asserted.
Priority Vectors are compared field by field, from left to right. The left most fields are relatively more important, and therefore their values are controlling. For example, if a first priority vector has a TDA Valid field 905 that is True, and the TDA Valid field 905 of a second priority vector is false, then the first priority vector is of higher priority, and no further fields need be compared. However, if the TDA Valid field 905 in the second priority vector is also true, then the values of the next field to the right are compared. If the TPM Space field 910 is true in the first priority vector, and the TPM Space field 910 is false in the second priority vector, then the first priority vector is higher priority, and no further fields need be compared.
This process continues through potentially all of the fields shown in FIG. 9 . If the TPM Space fields of two priority vectors are both true, then the Below Threshold fields 915 are compared. If the first priority vector Below Threshold field 915 is true, and the second priority vector Below Threshold field 915 is false, then the first priority vector is higher priority, and no further comparisons are made. If the Below Threshold fields 915 are both true, then the Priority fields 920 are compared. If the Priority field contains a higher value in one of the priority vectors being compared, then that priority vector is higher priority, and the comparison ends. If both priority vectors have the same value in the Priority field 920 , then the CL Predicted field 925 values are compared. If either of the priority vectors has a larger CL Predicted field value, then that priority vector is higher priority. If the values of the CL Predicted fields are the same, then the value in the Tokens Predicted fields 930 are compared. If one of the priority vectors has a higher Tokens Predicted field value than the other priority vector, then it is higher priority. If at that point the two priority vectors being compared have equal Tokens Predicted field 930 values, then a random selection is made to determine which of the priority vectors being compared is higher priority.
FIG. 10 shows an example embodiment of request logic used during request processing within the first arbitration stage 400 as shown in FIG. 4 . The logic in FIG. 10 is shown to include AND gate 1004 , AND gate 1008 , inverter 1006 , OR gate 1010 , OR gate 1016 , inverter 1024 , and AND gate 1026 . The inputs to AND gate 1004 are Transmit Below Threshold N 1000 and Transmit Data Request N 1002 shown for purposes of example as Transmit Below Threshold 0 and Transmit Data Request 0. Note that the logic for Transmit Below Threshold 0 and Transmit Data 0 are repeated for Transmit Below Threshold 1 through N, where N is the total number of possible transmit data requesters.
The inputs Transmit Below Threshold 1000 and Transmit Data Request 1002 are fed to AND gate 1004 . Also, the inverted Transmit Below Threshold 1000 and Transmit Data 0 are fed to AND gate 1008 . The output of AND gate 1004 , is signal XD 0 H 1012 which is an input into OR gate 1010 . Other outputs of identical logic for other transmit data request signals and transmit below threshold signals also are fed into OR gate 1010 , up through signal XD 31 H. The output of AND gate 1008 is signal XD 0 L 1014 . It is input into OR gate 1016 along with signals similarly derived by identical logic, namely XD 1 L-XD 31 L.
The output of OR gate 1010 is the signal Transmit Data High 1022 . Signal Transmit Data High 1022 is also fed through inverter 1024 and then into AND gate 1026 along with the output from OR gate 1016 . The output of AND gate 1026 is the signal Transmit Data Low 1028 .
The signal Transmit Data 0 (XMIT_DATA(0)) 1002 corresponds with Transmit Data 0 406 as shown in FIG. 4 . Similarly, Transmit Data 1 through Transmit Data 31 in 406 of FIG. 4 are processed by identical logic as shown for Transmit Data 0 1002 in FIG. 10 . The signal Transmit Data High 1022 corresponds with signal Transmit Data High 414 as shown in FIG. 4 . The signal Transmit Data Low 1028 corresponds with the signal Transmit Data Low 4016 as shown in FIG. 4 .
During operation of the elements shown in FIG. 10, the requests for the DMA 225 by the Control Logic 215 to move data from the host memory into transmit FIFOs in the adapter are processed, during the request processing phase of operation, by the logic shown to derive the outputs Transmit Data High 1022 and Transmit Data low 1028 .
Further during request processing in stage 1 of the arbitration system shown in FIG. 4, transmit descriptor requests are processed by logic similar to the logic shown in FIG. 10 for transmit data requests. The logic for processing transmit descriptor requests is the same as shown in FIG. 10, but having different input signals. Specifically, XMIT_DATA (0) is replaced by XMIT_DESC(0) (element 408 as shown in FIG. 4 ). The signal XMIT_DESC(0) is asserted when there is a transmit descriptor request for the FIFO corresponding with Transmit Queue 0. XMIT_DESC_H ( 418 in FIG. 4) and XMIT_DESC_L ( 420 in FIG. 4) are therefore derived identically as XMIT_DATA_H 1022 and XMIT_DATA_L 1028 , albeit from the inputs XMIT_DESC(0)-(31) rather than XMIT_DATA(0)-(31).
FIG. 11 shows an example embodiment of request logic for processing receive data requests in the first arbitration stage 400 as shown in FIG. 4 . The elements of FIG. 11 operate during the request processing phase of operation. The logic shown in FIG. 11 includes OR gate 1104 , AND gate 1106 , inverter 1112 , and AND gate 1114 . The inputs to OR gate 1104 are signals RD 0 through RD 7 . The signals RD 0 through RD 7 1102 correspond with signals Receive Data Request 0 through Receive Data Request 410 in FIG. 4 . The signal Receive Above Threshold 1100 is generated by the Control Logic 215 and indicates when asserted that the occupancy level of the Reassembly Memory 211 is above a programmable threshold. Thus, Receive Above Threshold signal 1100 indicates that Reassembly Memory 211 is running out of available space. The output of the OR gate 1104 is fed both into AND gate 1106 and AND gate 1114 . Also fed into AND gate 1106 is signal receive above threshold 1100 . Also fed into AND gate 1114 is the inverse of signal Receive Above Threshold 1100 .
The output of AND gate 1106 is Receive Data High signal 1108 . The output of AND gate 1114 is the Receive Data Low 1110 . Signal Receive Data High 1108 corresponds with signal Receive Data High 422 as shown in FIG. 4 . Signal Receive Data Low 1110 corresponds with signal Receive Data Low 424 as shown in FIG. 4 .
FIG. 12 shows an example embodiment of logic in the first arbitration stage 400 as shown in FIG. 4 for processing receive descriptor requests during the request processing phase of operation. The logic in FIG. 12 is shown to include an OR gate 1204 , an AND gate 1206 , an inverter 1210 , and an AND gate 1212 . A Receive Descriptor Threshold signal 1200 is asserted when an entry in the Receive Descriptor Array for any one of the 8 Receive Queues in Host Memory has less than a predetermined number of receive descriptors, for example, zero receive descriptors. The input Receive Descriptor 0 (RCV_DESC(0)) through Receive Descriptor 7 (RCV_DESC(7)) 1202 into OR gate 1204 corresponds with Receive. Descriptor 0 through Receive Descriptor 7 signals 412 as shown in FIG. 4 .
The output of OR gate 1204 is fed into both AND gate 1206 and AND gate 1212 . The signal Receive Descriptor Threshold 1200 is fed into AND gate 1206 and inverted by inverter 1210 and the inverted signal is subsequently fed to AND gate 1212 . The output 1206 is signal Receive Descriptor High 1208 and corresponds with signal Receive Descriptor High 426 as shown in FIG. 4 . The output of AND gate 1212 is the signal Receive Descriptor Low 1214 which corresponds with the signal Receive Descriptor Low 428 as shown in FIG. 4 .
FIG. 13 is an example embodiment of logic in the second arbitration stage 402 as shown in FIG. 4 for processing transmit requests during request processing. The logic in FIG. 13 is shown including an OR gate 1310 , an OR gate 1312 , an inverter 1316 , and an AND gate 1318 . The inputs into OR gate 1310 are Transmit Data High signal 1300 , Transmit Descriptor High signal 1302 , and Transmit Status signal 1304 . The inputs to OR gate 1312 are Transmit Data Low signal 1306 , Transmit Descriptor Low signal 1308 . The output of OR gate 1310 is Transmit DMA High signal 1314 , the output of OR gate 1312 is input into AND gate 1318 . Further, the output of OR gate 1310 is also fed into inverter 1316 , and the inverted signal subsequently into AND gate 1318 . The output of AND gate 1318 is Transmit DMA Low signal 1320 .
The signal Transmit Data High 1300 corresponds with signal Transmit Data High 414 as shown in FIG. 4 . Similarly, signal 1302 Transmit Descriptor High corresponds with signal Transmit Descriptor High 418 , and the signal Transmit Status 1304 corresponds with the signal Transmit Status 430 . Also, the signal Transmit Data Low 1306 corresponds with the signal Transmit Data Low 416 , and the signal Transmit Descriptor Low 1308 corresponds with the signal Transmit Descriptor Low 420 as shown in FIG. 4 . The signal Transmit DMA High 1314 in FIG. 13 corresponds with the signal Transmit DMA high 434 and the signal Transmit DMA Low 1320 corresponds with the signal 436 .
FIG. 14 shows an example embodiment of logic for processing transfer requests within the second arbitration stage 402 as shown in FIG. 4 . The logic shown in FIG. 14 is used during request processing. The logic in FIG. 14 is shown to include an OR gate 1410 , an OR gate 1412 , an inverter 1416 , and an AND gate 1420 . The inputs to OR gate 1410 are the signal Receive Data High 1400 , the signal Receive Descriptor High 1402 , and the signal Receive Status 1404 .
The inputs to OR gate 1412 are the signal Receive Data Low 1406 and the signal Receive Descriptor Low 1408 . The output of OR gate 1410 is the signal Receive DMA High 1418 . The output of OR gate 1410 is also fed through inverter 1416 and subsequently the inverted signal is passed to AND gate 1420 . Another input of AND gate 1420 is the output of OR gate 1412 . The output of AND gate 1420 is the signal Receive DMA low 1422 .
The signal Receive Data High 1400 corresponds with the signal Receive Data High 422 in FIG. 4 . Similarly, the signal Receive Descriptor high 1402 corresponds with the signal Receive Descriptor High 426 , and the signal Receive Status 1404 corresponds with the signal Receive Status 432 . The signal 1406 Receive Data Low corresponds with the signal Receive Data Low 434 in FIG. 4 and the signal Receive Descriptor Low 1408 corresponds with the signal Receive Descriptor Low 428 . The signal Receive DMA High 1418 corresponds with the signal Receive DMA High 438 in FIG. 4 and the signal Receive DMA Low 1422 corresponds with the signal Receive DMA Low 432 .
FIG. 15 shows an example embodiment of logic in the third arbitration stage as shown in FIG. 4 used for request processing. The logic in FIG. 15 shows OR gate 1508 . The inputs to the OR gate 1508 are Transmit DMA High signal 1500 , Transmit DMA Low signal 1502 , Receive DMA High signal 1504 and a Receive DMA Low signal 1506 . The output of OR gate 1508 is the signal Normal Request Selected 1510 . The signal Normal Request Selected 1510 is passed through an inverter 1512 with the resultant inverted signal being passed as input into AND gate 1513 . The AND gate 1513 further has as input the signal Error and Maintenance Request 1516 , corresponding with signal 470 as shown in FIG. 4 . The output of the AND gate 1513 is Error and Maintenance Request selected signal 1514 .
The signal 1500 Transmit DMA High corresponds with the signal 434 Transmit DMA High as shown in FIG. 4 . Similarly, the signal Transmit DMA Low 1502 corresponds with the signal Transmit DMA Low 436 , and the signal Receive DMA High 1504 corresponds with the signal Receive DMA High 438 . Also, the signal DMA Low 1506 corresponds with a signal DMA Low 440 in FIG. 4, and the signal Normal Request Selected 1510 corresponds with the signal 462 as shown in FIG. 4 . And the signal Error and Maintenance Request 1514 corresponds with the signal Error and Maintenance Status Update Request Selected 467 as shown in FIG. 4 .
While the invention has been described with reference to specific example embodiments, the description is not meant to be construed in a limiting sense. Various modifications of the disclosed embodiment, as well as other embodiments of the invention, will be apparent to person skilled in the art upon reference to this description. It is therefore contemplated that the appended claims will cover any such modifications or embodiments which fall within the true scope of the invention. | In accordance with principles of the invention, there is provided an arbitration system for multiple requesters of a shared data transfer resource, such as a system bus or a peripheral bus. The disclosed system arbitrates among multiple classes of requesters which are divided into multiple levels of a request hierarchy. In the example embodiment, the multiple requesters include logic for processing received data from the network, logic for processing data to be transmitted onto the network, logic for moving transmit and receive descriptors between the host memory and the adapter, logic for reporting status from the adapter to the host, and logic for generating an error and maintenance status update from the adapter to the host. The new system ensures fairness between transmit and receive processes, that FIFOs associated with transmit queues are not underrun, and further than notification of non-error and maintenance status changes are processed with minimal latency. | 6 |
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation of U.S. patent application Ser. No. 11/405,088, filed on Apr. 17, 2006, which is a continuation of U.S. patent application Ser. No. 10/822,502, filed on Apr. 12, 2004, which issued as U.S. Pat. No. 7,058,405, which is a continuation of U.S. patent application Ser. No. 10/328,623, and filed Dec. 23, 2002, which issued as U.S. Pat. No. 6,735,443, which claims priority from U.S. Provisional Application No. 60/392,211 filed on Jun. 28, 2002, all of which are incorporated by reference as if fully set forth.
FIELD OF THE INVENTION
[0002] The present invention relates to wireless communication systems. In particular, the invention relates to database processing of information for user equipment (UE) handover.
BACKGROUND
[0003] User equipment (UE) in wireless communication systems are beginning to provide functionality for internet/public service telephone network (PSTN) access via multiple wireless systems (such as (WLANs), Bluetooth® a registered trademark for a wireless network, universal mobile telecommunications system (UMTS), general packet radio service (GPRS), etc.). Hence, there is a growing need for these systems to work with each other in order for a UE to handover from one technology to another.
[0004] To assist in a handover, a wireless communication system base station can relay to a UE the information pertaining to outside systems. Thus, a base station needs to retain and constantly update information about the other systems. Retrieval of the information about another system is possible through secure inter-system connections (such as via an IP-cloud, for example) under roaming agreements. However, it is a deployment challenge to maintain and update such information about other systems. Hence there is a need for an alternate source to assist the base station in supplying the outside system information in order to eliminate the need for explicit inter-system connections and communications for this purpose.
SUMMARY
[0005] The present invention employs a technique for obtaining and updating data relating to neighboring wireless systems.
BRIEF DESCRIPTION OF THE FIGURES
[0006] FIG. 1 is a simplified diagram showing a plurality of wireless systems and user equipments within the wireless systems, which may employ the technique and principles of the present invention to great advantage.
[0007] FIG. 2 is a flow diagram useful in explaining the principles of the present invention and a method to implement such a system.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0008] FIG. 1 shows a multimode UE 101 operating within a wireless system 102 having an associated base station (BS) 102 b, while also being able to detect multiple surrounding wireless systems 103 - 105 . Upon detection of information from wireless systems 103 - 105 , UE 101 sends the current information to BS 102 b of system or systems 103 - 105 . BS 102 b can then update its database based on this new information from UE 101 . Likewise, subsequent handovers of UE 101 to other base stations can provide base station database updates. For example, after handover to wireless system 103 , UE 101 sends information pertaining to the most recently resident system (i.e., system 102 ), to base station (BS) 103 b, which then updates its database accordingly.
[0009] FIG. 2 shows a process flow diagram for the exchange of information between BS 102 b and UE 101 . Although this process is shown with a single UE for simplicity in explanation, multiple UEs may interact with BS 102 b at the same time. System information that is sent from a UE to the BS and vice versa may include, but is not limited to: geo-location of a UE, new system, congestion at the network and failure to detect a network.
[0010] At UE-S 1 , UE 101 obtains information relating to network 104 , for example. At step UE-S 2 , UE 101 transmits its identity to BS 102 b. At step BS-S 1 , BS 102 b receives the identity of UE 101 . At BS-S 2 BS 102 first authenticates the identity of UE 101 . This ensures that BS 102 b will not accept information about other systems from malicious UEs. Next, at step UE-S 2 , responsive to the authentication, the information is protectively encoded for integrity by UE 101 and, at step UE-S 3 , the protected information is transmitted by UE 101 to BS 102 b. A preferred method of protective encoding is via message authentication codes. Encryption may also be used to protect the information from being eavesdropped. At step BS-S 3 , BS 102 b verifies the integrity of the information. At step BS-S 4 , BS 102 b accepts the information and updates its databases. Now that BS 102 b has updated its database, BS 102 b, at step BS-S 5 , may communicate with adjacent systems 103 - 105 at regular intervals or triggered instants of time to validate the information updates received from UE 101 . Corrections to the database, if needed are made at step BS-S 6 .
[0011] System efficiency can be gained by BS 102 b taking a proactive role in letting UE 101 know of its surrounding systems, at step BS-S 7 . Hence, UE 101 need not send any information if its resident system is on the list provided by BS 102 b. This reduces radio traffic due to multiple UEs sending similar information.
[0012] This database stored in each BS is used for cell re-planning and system layover during deployment of additional networks. For example, consider a UMTS system overlaid over disjointed WLANs. The information gathered at the UMTS base station is used for planning WLAN network in that area. System 102 gets geo-locations of different UEs as they communicate about other systems (say System 103 ). The operator can use the geo-location of each UE that reported about system 103 to approximate the coverage of system 103 . This approximate coverage area can be used to plug coverage holes or future deployment planning of system 103 . | A wireless communication system includes a base station that receives information regarding neighboring wireless systems and updates and stores this information for use in handover of user equipments (UEs). | 7 |
FIELD OF THE INVENTION
The present invention relates to multilevel data-storage hierarchies, more particularly to the control thereof with respect to data-storage allocated for data resident in upper levels of the data-storage hierarchies.
BACKGROUND OF THE INVENTION
Peripheral storage hierarchies have been used for years for providing an apparent store as suggested by Eden, et al in U.S. Pat. No. 3,569,938. Eden, et al teach that in a demand paging or request system, caching data in a cachetype, high-speed front store (buffer) can make a peripheral storage system appear to have a large capacity, yet provide rapid access to data; rapid access being faster than that provided by the normal backing store. Eden, et al also teach that the backing store can be a retentive store, such as magnetic tape recorders and magnetic disk recorders while the front store can be a volatile store, such as a magnetic core store. With the advances in data-storage technology, the front store typically includes semiconductive type data-storage elements. U.S. Pat. No. 3,839,704 shows another form of such a storage hierarchy. An important aspect of storage hierarchies is good performance at low cost.
Storage hierarchies have taken diverse forms. For example, in accordance with the Eden, et al U.S. Pat. No. 3,569,938 a single high-speed store serviced several users. U.S. Pat. No. 3,735,360 shows that each processor can have its own high-speed store or cache. Performance of storage hierarchies also is affected by the algorithms and other controls used to place predetermined data into the cache or high-speed storage portion. Along this line, U.S. Pat. No. 3,898,624 shows that varying the time of fetching data from a backing store to a front or caching store can be selected by computer operator in accordance with the programs being executed in a using CPU. In this manner, it is hoped that the data resident in the cache or upper level of the hierarchy will be that data needed by the CPU while other excess data is not resident in the cache. This arrangement allows more useful data to be stored in the higher level storage portion. All of these operations become quite intricate. Accordingly, evaluation programs for storage hierarchies have been used to evaluate how best to manage a storage hierarchy. U.S. Pat. Nos. 3,964,028 and 4,068,304 show performance monitoring of storage hierarchies for achieving these goals. Even at that, much remains to be done in various types of storage hierarchies for enhancing optimum performance while ensuring data integrity. Much of the work with respect to storage hierarchies has occurred in the cache and main memory combinations connected to a using CPU. The principles and teachings from a cached main memory relate directly to caching and buffering peripheral systems, as originally suggested by Eden et al, supra. Of course, main memory has been used prior to Eden, et al for buffering or caching data from a magnetic tape and disk unit for a CPU, i.e. a main memory was not only used as a CPU working store but also as a buffer for peripheral devices.
The performance monitoring referred to above has indicated that it is not always in the best interests of total data-processing performance and integrity to always use a caching buffer interposed between a using unit and a backing store. For example, U.S. Pat. No. 4,075,686 teaches that a cache can be turned on and off by special instructions for selectively bypassing the cache. Further, the backing store or memory was segmented into various devices with some of the devices or segments being bypassed, such as for serial or sequential input/output operations. U.S. Pat. No. 4,268,907 teaches that for a command specifying the fetching of data words, an indicator flag is set to a predetermined state. Such flag conditions replacement circuits to respond to subsequent predetermined commands to bypass cache storage for subsequently fetched data words when the indicator flag is in the predetermined state to prevent replacement of extensive numbers of data instructions already stored in cache during the execution of such instructions. Interestingly, U.S. Pat. No. 4,189,770 shows bypassing cache for operands, but using cache for storing instructions.
Disk storage apparatus, also referred to as direct access storage devices (DASD), provide large quantities of random-access nonvolatile data-storage for data processing. Caching the DASD, as suggested above, provides a storage hierarchy with the performance and throughput capability better than that of DASD. Such performance improvement is obtained principally by maximizing the number of data-storage accesses which can be satisfied by accessing a copy of the data in the cache rather than by directly accessing the DASD. Management of the data-storage hierarchy includes dynamically entering data into and deleting data from the cache with the intent of increasing the proportion of the number of accesses that can be satisfied through the cache. While such management tends to reduce the size of a front store for controlling its costs, it has been observed that data does not always fill the record tracks of DASD, hence further savings may be available. All of the above shows a need for carefully managing utilization of data-storage space in a front store for controlling its costs. Such cost control is important where large blocks of data, such as 30 kilobytes or more are cached in a front store and such blocks are not always filled with data signals.
The management of data-storage apparatus for ensuring full utilization of such space available in any data storage unit includes storing variable-length data. For example, U.S. Pat. No. 3,739,352, shows a microprogrammed processor associated with a so-called "free-field" memory in which operands of any length in terms of number of bits can be processed. The free-field memory is addressed by an address register that points to the boundary between any two bits stored in the memory as the start of a field and indicates the number of bits in the field up to a maximum bit capacity of the memory. While this technique certainly appears to provide for a maximal packing of a given memory (data-storage unit), when such data is replaced by other data the probability of the replacing data having an extent (number of bits) equal to the data being replaced is relatively small. This means that each time data is replaced that the memory must be reformatted if the storage efficiency is to be maintained. Accordingly, this technique, while probably valuable for many applications, is not applicable to a front-store/back-store data-storage hierarchy because of the data replacement operations. As a result of such a scheme, it can be easily envisioned that fragmentation of data would occur which requires extensive and time-consuming management techniques not desired in a peripheral data-storage hierarchy.
A second U.S. Pat. No. 3,824,561 relates to storing groups of variable-length data elements which are allocated to storage addresses by means of apparatus and methods using characteristic data sets which define the characteristics of each data element in the group to be stored. This technique requires that the data sets be scanned in two directions. On a first pass, information as to the length and boundary requirements of each element are accumulated, then on a second pass addresses are allocated to each element to eliminate gaps in the group while maintaining proper boundary alignment. Again, this technique has value in certain applications but in the data-storage hierarchy, the replacment requirements plus the requirement of relatively low cost prohibit the complicated control. Performance requirements of a peripheral data-storage hierarchy are at odds with the first and second time-consuming pass requirements for doing an allocation. Accordingly, while this technique can provide efficient utilization of a data-storage unit, the techniques are not applicable to a data-storage hierarchy front store management where replacement and performance are intermingled with allocations of data-storage space for variable length data.
U.S. Pat. No. 4,027,288 shows using a character set including a beginning delimiter character and an ending delimiter character such that information segments may be of any length up to the capacity of the storage mechanism. Automatic data-storage allocation and reclamation of unused storage space as strings of data increase or decrease in size is provided for. This system employs symbolic addressing data on a magnetic tape wherein delimiter signals and sequential operations can take advantage of the described data-packing technique. For a random-access memory which is found in most front stores of a data-storage hierarchy, this technique is not applicable for achieving data packing while maintaining low cost and good performance.
U.S. Pat. No. 4,035,778 shows allocation of working space in a main memory of a host processor which optimizes the allocation by adjusting the size of the working set for each competing program. In a sense, the working memory can be considered as a buffer in the data-storage hierarchy wherein the host processor has a close-working association with the front store, i.e. the working memory. The techniques of this patent also relate to replacement controls such that the allocations of the working space is adjusted through replacement techniques. Peripheral data-storage hierarchies, because of the loose-coupling to the host processor, cannot take advantage of the described technique.
In a peripheral data-storage unit, U.S. Pat. No. 4,103,329 shows handling data represented by variable field length for using less data-storage. The bit fields are handled independently in the natural storage addressing elements and boundaries. This patent shows initializing a displacement register to contain an element displacement from a base address which contains the first bit of a desired bit field. While such a technique is certainly appropriate for packing data into a main memory for use by a host processor, the complexity and tracking of all of such data wherein the quantity of data is in the megabyte range becomes excessively expensive. Accordingly, these later-described techniques are also not fully satisfactory for managing a front store of a peripheral data-storage hierarchy.
Yet other techniques employed for improving utilization of data-storage apparatus include that described in the IBM TECHNICAL DISCLOSURE BULLETIN by Paddock, et al, Vol. 14, No. 7, December 1971, pages 1955 through 1957. This article shows an asymmetrical high-speed storage consisting of an 8 KB (kilobytes) area and two 4 KB areas, each area has a separate directory. Apparently smaller sets of data would be stored in the 4 KB areas while larger sets of data would be stored in the 8 KB area. Such a technique does not address the suitability of managing a front store where relatively large blocks of variable length data, i.e. 30 KB or greater are to be transferred as units. In another IBM TECHNICAL DISCLOSURE BULLETIN article by Gates, et al, "Multiword Size Storage" in Vol. 14, No. 8, January, 1969, pages 1019-1020 shows managing a data-storage apparatus for avoiding wasting or nonuse of storage bits due to difference in word sizes of data. The techniques of this article relate to storing words having two different sizes and alternating the storage such that no unused disks are employed. This article approaches the management of a data-storage apparatus only for an extremely limited set of data formats and hence is not applicable to a general storage apparatus.
Even with all of the above-described apparatus and techniques for managing a data-storage apparatus for maximizing utilization. There still is needed a relatively simple but effective management apparatus and method which can handle large units of data at relatively low cost while maximizing data-storage utilization and preserving high performance.
SUMMARY OF THE INVENTION
In accordance with the invention, data-storage apparatus has allocatable data-storage spaces each having a data-storage capacity less than a maximal capacity required for given data transfers. Upon each incoming data transfer, an initial maximal allocation of data-storage space in the data-storage unit is made for the expected data. The data is then transferred to the allocated data-storage space. Upon completion of the data transfer, an examination is made of which allocated data-storage spaces actually received none of the incoming data. All of those allocated data-storage spaces receiving no such data are then deallocated and allowed to be used for storing other data.
In another context, a maximal initial allocation of data storage space is made in accordance with the size of a maximal data transfer and upon completion of the data transfer the initial allocation is reduced to the size of the actual data transfer with all remaining portions of the allocated data-storage spaces being deallocated.
The foregoing and other objects, features, and advantages of the invention will be apparent from the following more particular description of the preferred embodiments of the invention, as illustrated in the accompanying drawings.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is a block-flow diagram illustrating an operation of the present invention for a data-storage unit accessible through a data-storage directory.
FIG. 2 is a block diagram of a preferred implementation of the invention within a peripheral data-storage hierarchy for implementing the techniques shown in FIG. 1.
FIG. 3 is a machine operations chart illustrating the operations of the FIG. 2 illustrated system using methods shown in FIG. 1.
FIG. 4 is a logic diagram for showing transferring a plurality of segments of data into a data-storage apparatus using the techniques set forth in FIG. 1.
FIG. 5 shows a directory usable with the FIGS. 1 and 2 illustrated data-storage apparatus.
DETAILED DESCRIPTION
Referring now more particularly to the drawings, like numerals indicate like parts and structural features in the various diagrams. As shown in FIGS. 1 and 2, one or more using units 10, such as central processing units, host processors and the like, are connected via peripheral connections 11 to storage director 12. Storage director 12 is suitably connected via a device interface 13 to a plurality of direct access storage devices (DASD) 14. A cache 15 selectively couples DASD 14 to one or more of the units 10 via input/output connection 11. Access to data stored in the cache 15 is via directory 16. A using unit 10 requests data access to the storage subsystem including front store or cache 15 and backing store or DASD 14 by using an address identified for DASD 14. Such address, when stored in directory 16, refers to data stored in cache 15 such that the data-access request can be satisfied without referring to DASD 14. Operations of the storage system is under control of a programmed processor 17 which includes a control memory 18 and a processing unit 19. Control memory 18 stores program indicia for enabling the processing unit 19 to exercise suitable control over cache 15, directory 16 and DASD 14 and facilitate communications with using units 10. Most of the functions performed by programmed processor 17 in response to the stored program indicia are well known data-storage functions for storage systems of the type described and which are not detailed for that reason.
Directory 16 has a plurality of registers, as later detailed with respect to FIG. 5; each of which includes a stored DASD address (DASD ADDR) 20 which identifies the DASD 14 address which is intended to store or is actually storing data that is currently stored at an addressable portion of cache 15. The cache 15 storage location is indicated by cache address pointer P1 contained in section 22 of each directory 16 register or can be indicated by which directory 16 register is storing DASD ADDR; i.e. directory 16 register addresses are mapped to cache 15 addressable data-storage spaces. In accordance with the invention, cache 15 has allocatable data-storage spaces (sets of addressable data-storage register which are allocated as a single unit) having a capacity smaller than the data-storage capacity of a data-storage track 21 on DASD 14 pointed to by the DASD address 20 in directory 16. Preferably the capacity of the allocatable data-storage space in cache 15 is an integral submultiple of the maximum capacity of the data-storage track 21. For the present description the allocatable data-storage space of cache 15 is one-third the capacity of the DASD 14 track capacity. Three cache 15 addresses are required to address contents of a complete DASD track stored in cache 15. This addressing is achieved by having an address pointer P1 in section 22 of directory 16 identifying an allocatable data-storage space 23 of cache 15 for storing a first one-third portion of a DASD 14 track. In this one portion of allocatable data-storage space 23 are a pair of pointers P2, P3, respectively in spaces 24 and 26. P2 contains an address pointing to allocatable data-storage space 25 of cache 15 which stores the second one-third portion of track 14 while P3 points to an addressable, allocatable data-storage space 27 of cache 15 which stores the third one-third portion of track 14. In this manner the three allocatable data-storage spaces of cache 15 are concatenated to store the data contents of one track. It is to be understood that the number of said multiples of allocatable units in cache 15 may be a number other than three and that the additional pointers such as pointers P2 and P3 instead of being stored in the first allocatable space 23 pointed to by directory 16 may in fact be stored in area 22 along with pointer P1 in directory 16. Storing the addresses P2, P3 within cache 15 simplifies directory 16's structure; it does require one additional access to cache 15 for setting up data transfers, as will become apparent.
In accordance with the invention, when cache 15 is to receive data from either a using unit 10 or from DASD 14, programmed processor 17 will not have an indication of the extent of data which cache 15 will receive. That is, it may be a full track of data or less than a full track of data. Accordingly, each time cache 15 is to receive data, three allocatable data-storage spaces of cache 15 are allocated for the upcoming data transfer. Following such allocation, the data transfer ensues. Upon completion of the data transfer, programmed processor 17 examines which of the allocated data-storage spaces, such as 23, 25 and 27, have in fact received data for storage. Those allocated data-storage spaces of cache 15 not receiving any data during such data transfer are then deallocated, via appropriate pointers being zeroed and are made available for reallocation of data not related to the just-addressed DASD 14 track. In this manner, management of cache 15 data-storage space allows a greater number of tracks to be effectively stored in cache 15 with a relatively smaller cache capacity, i.e. reduces cost. In another view, if the same size cache 15 is used, then a greater performance is provided because the contents of a greater number of addressable DASD 14 data-storage tracks can be stored in cache 15. Cache 15, of course, has a large plurality of such allocatable data-storage spaces, as collectively indicated by numeral 28 and ellipsis 29.
The scattering of data from a single addressable data-storage track into a plurality of unrelated segments or data-storage spaces of cache 15 when high-speed data transfers are involved requires rapid concatenation and some buffering during the data transfer. For enhanced flow of data signals into and out of cache 15, as best seen in FIGS. 1 and 2, a plurality of system storageaddress registers 30 are provided. SSAR-0 receives pointer P1 from directory 16 in preparation for accessing allocated data-storage space 23. SSAR-1 and SSAR-2 respectively receive pointers P2 and P3 from areas 24, 26 of allocated data-storage space 23. This action completes the preparation for an ensuing data transfer. FIG. 4 shows how a plurality of address registers can quickly concatenate a plurality of addressable data-storage spaces for receiving a highspeed burst of data signals.
Upon each received data-access request, programmed processor 17 examines directory 16 to determine whether or not an associated allocatable data-storage space has been allocated to the DASD address received from using unit 10. If there is no match, then a cache-miss occurs, as indicated by numeral 35. Such a cache-miss can result in a data promotion from DASD 14 into cache 15, as will be later detailed. Such a miss activates processing unit 19 to access control store 18 for executing program 36 which may result in transferring data from DASD 14 to cache 15. Further, a cache write-hit, which indicates data will be transferred from a using unit 10 into cache 15, results in programmed processor 17 responding, as indicated by arrow 37, to use program 36 for preparing cache 15 to receive data from host 10, which may include up to a full track of data the extent of which, of course, is not presently known to the data-storage system. In such a host write, the host data is preferably simultaneously written to DASD 14.
In any event, for cache 15 to receive data without any overrun exposure results in programmed processor 17 in responding to program 36 to execute program 40 for allocating one DASD track capacity in cache 15 and setting the pointers P1, P2 and P3 as may be required. For example, if no cache 15 data-storage space has been allocated, then three cache 15 data-storage spaces are allocated with the corresponding pointers being generated. If on the other hand only one data-storage space is currently allocated, then two more data-storage spaces are allocated with the corresponding pointers being generated, all of which is detailed later with respect to FIG. 3. Upon completion of executing program 40, programmed processor 17 executes program 41 which actually causes the transfer of data to the cache 15 from either host 10 or DASD 14, as the case may be. Upon completion of the data transfer, programmed processor 17 checks the ending address of the last byte of data transferred into cache 15 by executing program 42. This check identifies which allocated data-storage spaces in fact received no data during the data transfer; i.e. the ending address check determines which of the three allocated data-storage space last received data. Then programmed processor 17 by executing program 43 deallocates any unused cache allocations made for the data transfer. Of course, preparatory to the execution of programs 36 and 43 and thereafter, other programs 44 which are commonly found in data-storage subsystems are executed. Since such programs do not have a bearing on an understanding of the present invention, they are not detailed.
In program 40 it may be required that programmed processor 17 replaced existing data in cache 15. Free or unallocated data-storage spaces must be identified. This action is achieved by an LRU (least recently used) replacement control list 47, usually found in data-storage hierarchies, explained with respect to FIG. 5. LRU 47 includes identification of those allocatable data-storage spaces which are available for allocation. Accordingly, execution of program 40 by programmed processor 17 results in usage of MRU-LRU program 46 for scanning LRU 47 to allocate data-storage spaces. If sufficient allocatable data-storage spaces are found, then those spaces are allocated with no further activity. However, if no allocatable data-storage spaces are found, then programmed processor 17 uses replace program 45 for transferring data from a replaced one of the allocated data-storage spaces to DASD 14 using known replacement techniques. When DASD 14 is updated concurrently with cache 15, the cache 15 space is immediately reallocated to the incoming data without any prereplacing data transfers to DASD 14. In this manner, cache 15 can be always filled with promoted data. Program 48 enables programmed processor 17 to access cache 15 using known techniques; accordingly, this program is not detailed.
FIG. 2 illustrates a preferred embodiment of the invention as employed in a two-storage director 12 data-storage arrangement. Each storage director 12 includes a plurality of so-called channel adaptors 50, also separately denominated as CAA through CAH, which connect the respective storage directors 12 to a plurality of using units 10 via a plurality of input/output connections 11. Each storage director 12 includes a programmed processor 17 which, as usual, includes a processing unit 19 having a control store 18 which contains computer programs for performing the storagedirector functions. FIG. 2 shows the logical structure; i.e. the functions performed by processor 19 in executing the programs in control store 18. The programmed processor 17 includes programs constituting address and command evaluator ACE 52 which receive and evaluate using unit 10 supplied peripheral commands. Such functions are also performed in present day storage directors for noncached DASD as widely sold throughout the world and are a part of other programs 44 in FIG. 1. The programmed processor 17 also includes programs for direct access control DAC 53 which responds to commands evaluated and decoded by ACE 52 to control data transfers between using units 10 and DASD 14, as well as providing device commands to DASD 14 for performing well known DASD access and control functions. DAC 53 includes program 41 as well as programs for accessing DASD 14 included in other programs 44 relating to accessing DASDs 14 and transferring data between using units 10 and DASDs 14, all of which is well known. Programmed processor 17 further includes programs CAC 54 which is a cache access control for accessing cache 15. CD latches 59, one for each of the DASDs 14, are accessed by DAC 53 and CAC 54 respectively for determining whether to access cache 15 or DASD 14 directly and for setting the latches to D upon a cache miss. Connections from storage director 12 to DASDs 14 are via DASD circuits 55 which are constructed using known device adaptor and data-flow design techniques. Cache 15 is accessed via memory circuits (MEM CCTS) 56 which includes those circuits for generating addresses and access requests including SSARs 30. Cache 15 is a portion of a large random-access store 57, hereinafter referred to as a system store. It is preferred that cache 15 can simultaneously and independently handle data transfers with a DASD 14 and a host 10. The directory 16 and LRU 47 for cache 15 are also stored in system store 57. Additionally, any using unit 10 can command the storage directors 12 to keep data in cache, i.e. pin or bind the data to cache 15. For all bound tracks, it records a cache bound list 60, stored within directory 58 but shown separately for clarity, indicates to both storage directors 12 which data stored in cache 15 is to remain in cache 15. Such bound data is not listed in LRU 47 for preventing replace program 45 from reallocating cache 15 space.
Access to DASDs 14 is via a so-called daisy string arrangement in which a plurality of DASDs 14 are connected to the storage directors 12 via controllers 65, separately denominated as DCA through DCD. Each storage director 12 connects to the controllers 65 via a daisy-chain device connection 13. A radial connection of known design may also be employed. The operation of the FIG. 2 illustrated system in accordance with the invention is best understood by referring to FIG. 3, a machine operations chart.
Programmed processor 17 at 70 receives a storage-access request. This request is decoded and evaluated in ACE 52 using known techniques. At 71, programmed processor 17 DAC 53 portion examines the CD latch 59 (FIG. 2) related to the DASD 14 addressed in the received storage-access request to determine whether cache 15 or only DASD 14 to the exclusion of cache 15 is to be accessed. For a direct access, DASD 14 is accessed at 72 using usual DASD access methods. For a cache C access, programmed processor 17 searches directory 16 at 73 to determine whether or not the track requested in the received storage-access request (I/O command) has allocated space in cache 15. In this regard it is noted that some commands will require a direct connection to DASD 14 to the exclusion of cache 15. Accordingly, ACE 52 in detecting such a received I/O command sets latch 59 for the addressed DASD 14 to the direct mode "D". An example of such an I/O command is to recalibrate a DASD 14. Searches and SEARCH ID EQUAL commands can be performed for cache 15 accesses within directory 16, i.e. the commands are performed in a virtual manner not involving DASD 14. In the preferred embodiment directory 16 does not separately identify records in a track; only tracks are identified, no limitation thereto intended. Upon completion of the directory 16 search, programmed processor 17 at 74 determines whether or not a cache-hit has occurred. If a cache-hit occurred, which is preferred programmed processor 17 at 74A transfers the P1 stored in section 22 of the directory 16 register identified by the received DASD 14 address to SSAR-0; then it transfers P2 and P3 respectively to SSAR-1 and SSAR-2 from their respective storage locations.
At step 75, director 12 examines cache 15 to determine whether or not the record to be accessed is stored in cache 15 (record hit). If the addressed record is in cache 15 (record hit is yes), then additional segments may not be needed to successfully complete the ensuing data transfer. Then at step 76 the type of data transfer operation to be performed is examined. For a read operation R (transfer of data to a host 10), director 12 at step 77 transfers the requested data from cache 15 to the requesting host 10. Such transfer completes the operation permitting director 12 to exit the machine operation at 78 for performing other data processing operations. For a write operation W (transfer of data from a host 10) indicated at step 76, director 12 at step 80 examines the received host 10 supplied command for ascertaining if the write is a FORMAT write (access to DASD 14 is requested to the exclusion of cache 15) or any other form of write (cache 15 is to be utilized) is requested. For a FORMAT write, director 12 in step 81 deallocates any allocated cache 15 data-storage space and transfers the received data to DASD 14. For a nonformat write (FORMAT=0) at step 80, director 12 in step 82 transfers data from the requesting host 10 to both cache 15 and DASD 14 respective addressed data-storage areas. In this manner, cache 15 and DASD 14 always have identical copies of the same data. From steps 81 and 82, director 12 proceeds to other data processing operations via logic path 78. This operation allows less than a full track allocation in cache to handle successive data transfers (partial track allocations).
Returning to step 75, when director 12 does not find the addressed record (record hit is no), then for the impending data transfer to the cache, additional segments may be allocated for the ensuing data transfer. In steps 85 and 86 director 12 examines the values of P2 and P3. For either or both pointers being zero (no corresponding space has been allocated in cache 15), director 12 in step 86 allocates an additional segment to the track, as previously described and then proceeds to transfer data to cache 15 at 87. The step 87 data transfer can be a write from a host 10 to DASD 14 and cache 15, a read from DASD 14 to cache 15 and a host 10, or a staging data operation from DASD 14 to cache 15.
The post-transfer machine operations find director 12 examining cache 15 to determine which of the three allocated segments in fact received data from the just-completed data transfer. In step 88, director 12 examines a later-described "k-counter" 129 (FIG. 4) to ascertain the values 1, 2 or 3 which respectively indicate that one, two or three allocated segments (corresponding to P1, P2, P3) in fact received and are currently storing data. For k=1, director 12 in step 90 takes the segments 2 and 3 (also termed XM and YM, respectively) identifications and inserts same into the LRU list for making these segments available for allocation. In step 91, the corresponding pointers P2 and P3 are set to zero. For a value k=2 in step 88, director 12 in steps 92 and 93 inserts the third segment YM into the LRU list and sets pointer P3 to zero. For a value of k=3 in step 88, director 12 knows that all three segments have received and are currently storing data, hence it proceeds directly to do other data processing operations through logic path 78. Path 78 is also entered from steps 91 and 93, as well.
For a cache miss at 74 (hit=0), director 12 in steps 95 and 96 allocates three segments in cache 15 (XY, XM, YM) for the ensuing data transfer to cache 15 and sets the corresponding pointers P1, P2 and P3 in the respective SSAR's 0, 1 and 2. Then director 12 proceeds to the data transfer operation performed in step 87, as previously described.
In one embodiment of directory 16, each of the registers in directory 16 corresponded to a space 28 in cache 15. Hence, area 22 is dispensed with the register address within directory 16 also indicating (using base plus offset addressing) the beginning address in cache 15 of an associated space. Allocation then consists of inserting the appropriate DASD address in section 20 of such register. Addresses XM and YM respectively become pointers P2 and P3 and are stored in areas 24, 26 of the area 23 corresponding to address XY. Note there are no changes in directory 16 for these last two pointers. In the event that the last above-described directory 16 structures wherein a given register always is associated with a data-storage area of cache 15, then addresses P2 and P3 are inserted in these respective directory 16 registers; the registers for P2 and P3 are then omitted from LRU 47. The above completes setting up the pointers for the ensuing data transfer.
FIG. 4 illustrates cache 15 addressing circuits usable with the present invention. The data paths 100 extend from cache 15 through memory circuits 56 thence to DASD circuits 55 for data transfers with DASD 14. The data paths also extend to the channel adaptors 50 for data transfers with using unit 10, all as shown in FIG. 2. The data transfers between cache 15, adaptors 50 and DASD circuits 55 are under the control of usual automatic data-transfer circuits of known design and of current use in DASD storage systems. Such automatic transfer control circuits are shown as autocontrol 101 in FIG. 4 as being a part of memory circuits 56. Programmed processor 17 supplies a suitable start signal over line 102 to autocontrol 101. The description assumes the storage system address registers 30 have been loaded with the appropriate addresses P1, P2 and P3 received from programmed processor 17 respectively over address busses 110, 111 and 112. Such loading of address registers by a programmed processor is well known. Once autocontrol 101 receives the START signal, it supplies a cache 15 access enabling signal over line 103 to cache 15. As a result, cache 15 will receive addresses as later described for accessing data-storage registers within the cache. The access-control signal on line 103 will carry an indication of whether the operation is a read-from-cache operation or a write-to-cache operation. Many caches 15 contain known refresh circuits which interleave refresh cycles with data-access cycles. Each time cache 15 transfers a set of data signals over data path 100, it indicates a cycle of operation to autocontrol 101 over line 104. Autocontrol 101 has been preset in a known manner for transferring a given number of data signals between cache 15 and either DASD 14 or host 10. When data signals are being written into cache 15, autocontrol 101 may not know the number of signals to be received. In this instance, a second signal is supplied over start line 102 to turn autocontrol 101 off for removing the signal on line 103. For example, in a host-to-cache data transfer, the host using the IBM 370 interface architecture can send a socalled COMMAND OUT I/O tag signal indicating the end of the data transfer. Such I/O tag signal results in programmed processor 17 sending a second signal on start line 102 to indicate to autocontrol 101 to terminate the data transfer. Termination of the data transfer either internally to autocontrol 101 or to externally received commands is indicated to programmed processor 15 by an END signal supplied over line 105. For each cycle of cache 15 operation, autocontrol 101 emits an address incrementing signal over line 115. The incrementing signal goes to one and only one of the SSARs 30 as selected by an SSAR address received over bus 130 from programmed processor 17. The addressing of a plurality of address registers is well known and not described for that reason. When P1, P2 and P3 are loaded, the SSAR address signals received from programmed processor 17 will select SSAR-0. Decoder 131 decodes the address signal and supplies an AND circuit enabling signal over line 132 to AND circuits 116 and 120; AND circuit 116 passes the address incrementing signal on line 115 to SSAR-0 for incrementing the address contained therein. Decrementing can be used as well. Each time SSAR-0 is incremented, it supplies a set of address signals to AND circuits 120 for transmitting same over the address bus 123 to cache 15 for selecting the next data-storage location within the cache 15 addressed data-storage space for the data transfer. When the SSAR-0 has counted through all of the addressable data-storage locations within one data-storage space 28 of cache 15, it supplies a carry signal over line 126 through OR circuit 125 for incrementing segment counter 129. Segment counter 129, which counts segments having 2 k data-storage locations (k is an integer), has been preset to zero through a reset signal received from programmed processor 17 overline 140. Segment counter 129 supplies a zero signal over line 141 to decoder 131 for passing the received SSAR-0 address signal to decoding circuits resulting in the line 132 and enabling signal. When segment counter 129 is incremented by the SSAR-0 carry signal, it then supplies a one signal over line 142 to decoder 131.
Decoder 131 is of the type that can add one to the received SSAR address such that the line 132 AND-circuit enabling signal is removed and a new AND-circuit enabling signal is supplied over line 133. Such signal enables AND circuits 117 and 121 associated with SSAR-1. AND circuit 117 enables the address-incrementing signal on line 115 to increment SSAR-1 and then to supply address signals through AND circuits 121 to cache 15. In a similar manner SSAR-1 supplies its carry signal over line 127 to also increment segment counter 129 resulting in a two signal being supplied over line 143 to decoder 131. This causes decoder 131 to add two to the received SSAR address resulting in an AND-circuit enabling signal being sent only over line 134 to AND circuits 118 and 122 associated with SSAR-2. SSAR-2 then receives the address-incrementing signal and supplies the cache data-storage location signals to cache 15 for the third data-storage space being addressed in the sequence of operation.
Segment counter 129 is not restricted to counting segments of 2 k sizes. By providing a segment size register, the counter 129 can count segments having any arbitrary size or variably sized segments. For simplicity segment sizes of 2 k are preferred.
It is to be appreciated that a larger plurality of SSARs 30 may be provided, as indicated by ellipsis 147. As such, any three of the larger plurality of storage address registers may be used in sequencing cache 15 operation in accordance with the invention. Accordingly, there are a like greater plurality of AND circuits enabling lines indicated by ellipsis 148. In any event, the first storage address register which receives P1 is selected by programmed processor 17 in the usual manner. Programmed processor 17 then indicates which SSAR received the P1 address which starts a sequence of concatenated addresses within cache 15 for successively-accessed data-storage spaces 28. Accordingly, a variable number of data-storage spaces 28 can be used with a diversity of sizes of address spaces for receiving data signals. For example, if two types of DASD 14s are attached to the directors 12, two different sizes of data transfer units (data contents of two DASD tracks have different numbers of stored data bits) may be involved. From a first DASD 14 three data-storage spaces 28 may be concatenated for receiving data signals. For a larger and newer DASD 14, five of the data-storage spaces 28 of cache 14 may be used, and so forth. In the latter instance the director 12 keeps a table (not shown) relating each DASD device address with a unit size of data transfer such that the appropriate number of data-storage spaces 28 may be selected for each receiving data-transfer operation. Some DASD 14s are operated in a front store/back store concept such that a portion of the DASD is addressable separately in a track subunit such as one-third or one-fourth of a track. Other tracks within the same DASD 14 may be addressed only as whole track units. In this case the same principles of the invention can be applied equally. Of course, segment counter 129 has to be adjusted accordingly.
To effect the deallocation of spaces 28, segment counter 129 supplies the number of segments over bus 145 that have been accessed in the current sequence of data transfer operations. Referring back momentarily to FIG. 3, step 110 determines the value of segment counter 129.
FIG. 5 illustrates the operation of directory 16. Directory 16 includes a plurality of registers, each of which is uniquely associated with one and only one of the data-storage spaces 28 of cache 15. Access to directory 16 is based upon a received DASD 14 address as received over bus 150 from using units 10 via programmed processor 17. A hash circuit 151 analyzes and parses the received DASD address into well known hash classes. The entire address base of all DASDs 14 of a particular data-storage system are divided into classes in accordance with track number, device number and DASD cylinder number (cylinders are all record tracks at one radial location or address). Each hash class has a single register in a scatter index table SIT 152. The output of hash circuit 151 addresses one and only one register in SIT 152. SIT 152 stores the address of a directory 16 register having a DASD address in its section 20 residing in the hash class defined for the given SIT 152 register. Such address is supplied, as indicated by arrow 154, for selecting the indicated one of the directory 16 registers. Within each directory 16 register is a hash pointner (HASH P) 155 which points to the next directory 16 register containing a DASD address within the same hash class. The last directory 16 register in the singly-linked list contains all zeros or a special code indicating it is at the end-of-chain. Accordingly, to scan the directory 16 registers, programmed processor 17 activates hashing circuit 151 for accessing the directory 16 registers from SIT 152 and accesses the first register for comparing the DASD address contained in its section 20 with the received DASD address on bus 150, as indicated by compare circuit 157. If there is a favorable compare, a cache hit has occurred as indicated by a signal on line 158. In the practical embodiment, line 158 is a logic path within programmed processor 17 in a program of instruction, such as program 36. A noncompare is indicated by numeral 159, then the hash pointer 155 is read and the directory 16 register pointed to by that hash pointer has its DASD address portion compared in a like manner. This cycle repeats until either a favorable compare indicates a cache hit or an end-of-chain (EOC) occurs. In the case of EOC, as indicated by numeral 160, a cache miss has occurred.
Each of the directory 16 addresses can contain a P1 pointer in section 22. As mentioned earlier, the actual address of the directory 16 register may be associated with a data-storage area 28 in a linear fashion. By having a P1 section 22 no ordered relationship between directory 16 structure and the organization of cache 15 is required.
LRU 47 also resides within directory 16. Each of the registers of directory 16 has a portion 167 which contains a pointer which points to a directory 16 register corresponding to a data-storage space 28 of cache 15 which is one less recently used than the data storage space pointed to by the current register. In a similar manner, section 168 has a more-recently-used pointer pointing to a directory 16 register corresponding to a data-storage space 28 which is more recently used. Accordingly, sections 167 and 168 are a doubly-linked list of directory 16 registers constituting an indication of the recentness of usage of the various data-storage areas. The least recently used data-storage areas represented by a special code in the LRUP area. While the most recently used data-storage areas indicated by a special code in the MRUP area.
Control store 18 of programmed processor 17 contains socalled LRU and MRU anchors 165 and 166. The LRU anchor 165 contains the address of a directory 16 register which is least recently used, while MRU anchor 166 points to the directory 16 register corresponding to the data-storage space 28 which is most recently used. The updating of the doubly-linked list 167, 168 and the anchors 165, 166 is well known and not described for that reason. When either P2 or P3 is set to zero, as in steps 91 or 93 of FIG. 3, director 17 updates the doubly-linked list 167, 168 by making the corresponding cache 15 segments free (F-bit 171 is set to unity) and relink the freed segments at the LRU end portion of the linked list. Additionally, when DASD 14 is not concurrently updated with data updates in cache 15, LRU 47 then includes a status indicator for the corresponding data-storage spaces 28. M-BIT 170 indicates whether or not the data contents of the corresponding data-storage space 28 has been modified by using unit 10. When M-BIT 170 is zero, the corresponding data-storage space is available for deallocation. Since no data transfer from cache 15 to DASD 14 is required for reallocation, when M-BIT 170 is equal to one (data in cache 15 has been changed), before the corresponding data-storage space is available for reallocation, the data contents of the corresponding data-storage space 28 has to be moved to the associated data-storage area of DASD 14. When DASD 14 and cache 15 are concurrently updated, M-BIT 170 is dispensed with. F-BIT 171 indicates whether or not the data-storage space 28 is free (unallocated) and available for allocation. The LRU scan described with respect to steps 101 and 95 of FIG. 3 begins with the LRU anchor 165 indicated directory 16 register and scans the registers for F-BIT 171 equal to 1 using the doubly-linked list 167 and 168. If the scan finds no free spaces from the F-BITs 171 indicated data-storage spaces, then a second scan for the M-BITs 170=0 is made. Of course, each directory 16 register contains additional control information as indicated by ellipsis 175.
While the invention has been particularly shown and described with reference to preferred embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention. | A data-storage buffer transfers data signals with other units in relatively large blocks of data. Such large blocks storable in large address spaces are not always filled with meaningful data. To more efficiently use the data-storage space in the data-storage buffer, the allocatable unit or segment of the data buffer is made smaller than the data capacity of the large block. Each time a large block of data is to be written into the data buffer, a sufficient number of the segments for storing data of one large block is allocated for receiving the data. After the data of the one block is written into the data buffer, the allocated segments are examined; all of the allocated segments not storing data from the one large block are deallocated. The invention is particularly useful for data buffers acting as cached data storage for large-capacity direct-access storage devices (DASD) and are coupled to host processors programmed to operate with such DASD. The procedure is followed for data written into the caching data storage whether supplied by DASD or the host processors. | 8 |
BACKGROUND OF THE INVENTION
This invention relates to an electronic equipment device such as a small portable radiophone.
Referring to FIG. 8 which shows the construction of a conventional electronic equipment device of the type described, this electronic equipment device comprises a casing body 101, an antenna 102, a speaker (transmitter) 103, dial buttons 104 arranged in a 3×4 arrangement, and function buttons 105 for controlling various functions. Various electronic parts are mounted on a printed board 106, and an indicator such as an LED is mounted on one face of the printed board 106. A radio transceiver portion 108 is covered with a shield case. A casing cover 109 is provided with a receiver 110. A battery pack 111 is attached to the casing cover 110. The radio transceiver portion 108 is secured to the printed board 106, and then the printed board 10 is housed in the casing body 101, and then the casing cover 110 is put on the casing body 101. Finally, the casing cover 110 and the casing body 101 are fastened together by screws 112.
In the above conventional electronic equipment device, however, a shield construction, which effects the shielding of the radio transmitter portion 108 and the shielding of electronic circuitry (which includes those circuits constituting a speaking portion and a control portion) on the printed board 106 independently of each other, is complicated, and can be easily affected by a mechanical impact. Another problem is that the number of the component parts, as well as time and labor required for assembling the electronic equipment device, are large since the assembling should be carried out by screwing.
SUMMARY OF THE INVENTION
In view of the above-mentioned problems, it is an object of this invention to provide an electronic equipment device in which a radio transceiver and electronic circuits are shielded independently of each other by a simple construction, and the device has a rigid structure, and can be assembled easily.
According to the present invention, there is provided an electronic equipment device comprising:
a first printed board having electronic parts mounted thereon;
a second printed board having electronic parts mounted thereon;
an electrically-conductive frame interposed between the first and second printed boards to sealingly accommodate the electronic parts, mounted on the first and second printed boards, to shield the electronic parts; and
a resilient clamping member for clamping the two printed boards so as press them against the frame to electrically connect the two printed boards to the frame.
In the present invention, a radio transceiver portion is mounted on the first printed board, and a control circuit portion is mounted on the second printed board, and the frame is interposed between the first and second printed boards, with the electronic parts thereon facing the frame, to thereby provide a semi-assembly in which the two resilient clamping members grasp or clamp opposite side portions of this semi-assembly, respectively, to form an earth connection, so that the radio transceiver portion and the control circuit portion are shielded with the simple construction. Since the assembling is effected by the use of the resilient clamping members, the resultant assembly is mechanically rigid, and will not be twisted or deformed, and further, the number of the component parts, as well as time and labor required for assembling and disassembling the electronic equipment device, can be reduced.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an exploded, perspective view of an important portion of a structure of an electronic equipment according to the present invention;
FIG. 2 is an exploded, perspective view illustrating the whole of the structural portion of the above device;
FIG. 3 is a perspective view showing a back side of a second printed board in the above device;
FIG. 4 is a perspective view showing a front side of a first printed board and a back side of a metal frame in the above device;
FIGS. 5a and 5b are fragmentary, cross-sectional views showing an assembling construction of a printed board assembly in the above device;
FIGS. 6a and 6b are fragmentary, cross-sectional views showing an assembling construction of a casing body and a casing cover in the above device;
FIG. 6c is a fragmentary, perspective view showing retaining holes in the casing cover;
FIG. 7 is a fragmentary, cross-sectional view showing an assembling construction of the above device; and
FIG. 8 is an exploded, perspective view of a conventional electronic equipment device.
DESCRIPTION OF THE PREFERRED EMBODIMENT
FIG. 1 is an exploded, perspective view which shows an important portion of a structural portion of an electronic equipment device provided in accordance with the present invention. In FIG. 1, reference numeral 1 denotes a first printed board, reference numeral 2 a second printed board, reference numeral 3 a metal frame of a generally H-shaped cross-section, and reference numeral 4 a pair of resilient clamping members. FIG. 2 is an exploded, perspective view of the whole of the structural portion of the electronic equipment device. In FIG. 2, reference numeral 5 denotes a printed board assembly formed by combining the members of FIG. 1 together, reference numeral 6 a dial button sheet, reference numeral 7 a casing body, and reference numeral 8 a casing cover. Button holes 9 for respectively exposing the above buttons are formed through a front wall of the casing body 7. An antenna 10 is mounted at one end of the casing body 7.
In FIG. 1, electronic parts, such as a radio transmitter portion 11, a radio receiver portion 12 and a frequency synthesizer 13, are mounted on a front face of the first printed board 1. A strip-like earth portion 14 (indicated by hatching) for electrical connection to the metal frame 3 is formed on a peripheral edge portion of the printed board 1, and is also formed on the front face of the first printed board 1 and along borders around the electronic parts mounted thereon. A registration hole 15a of a circular shape is formed in a lower end portion of the first printed board 1 while a registration hole 15b of an oval shape is formed in an upper end portion thereof. Reference numeral 16 denotes a connector.
A plurality of dial button contacts 21 are formed on a front face of the second printed board 2. A liquid crystal display (LCD) 22 is secured by soldering to the second printed board 2 through a contact portion 22a. A calling buzzer 23 and an external connection terminal 24 are also secured by soldering to the second printed board 2. A microphone unit 25 is secured by soldering to the second printed board 2 within a U-shaped groove portion 24a formed in a mold portion of the external connection terminal 24. A strip-like earth portion 26 (indicated by hatching) is formed on each of the front and back faces of the second printed board 2 at a peripheral edge portion thereof. FIG. 3 shows the back face of the second printed board 2 having the earth portion 26 formed thereon. A connection connector 27, a microcomputer 28 and an IC 29 are secured by soldering to the back face of the second printed board 2. The second printed board 2 has a registration hole 30a of a circular shape and a registration hole 30b of an oval shape.
In FIG. 1, the metal frame 3 is diecast of magnesium, and has an outer shape similar to that of the first and second printed board 1 and 2. The metal frame 3 has a projected wall portion 31 formed on the outer peripheral edge portion thereof, so that this metal frame 3 has a H-shaped cross-section. A loose hole 32 is formed through the metal frame 3, and the connector 16 on the first printed board 1 and the connector 27 on the second printed board 2 are connected together through this loose hole 32. A pair of registration projections 33a and 33b are formed on a front face of the metal frame 3, and are adapted to be fitted respectively in the registration holes 30a and 30b in the second printed board 2. Retaining projections 34a and 34b are formed on each of the opposite side walls of the metal frame 3, and are adapted to be engaged respectively in retaining recesses (described later) in the casing body 7. As shown in FIG. 4, a projected wall portion 35 is formed on the outer peripheral edge portion of the back face of the metal frame 3, and has the same configuration as that of the earth portion 14 on the first printed board 1 so that the wall portion 35 can make contact with only this earth portion 14. Registration projections 36a and 36b are formed respectively on lower and upper end portions of the back face of the metal frame 3, and are adapted to be fitted respectively in the registration holes 15a and 15b in the first printed board 1.
As clearly shown in FIG. 1, each of the two resilient clamping members 4 is formed by bending a thin stainless steel sheet into a U-like cross-sectional shape, and a number of slits or notches are formed in each of opposite sides thereof. The resilient clamping member 4 is slightly curved inwardly in its entirety so to increase a clamping force. A pair of guide holes 4a and 4b are formed through each resilient clamping member 4 in registry with the two retaining projections 34a and 34b formed on the corresponding side wall of the metal frame 3.
The assembling of the electronic equipment device of this embodiment will now be described. In FIGS. 1, 3 and 4, the registration holes 15a and 15b in the first printed board 1 are fitted respectively on the registration projections 36a and 36b on the back face of the metal frame 3, and the registration holes 30a and 30b in the second printed board 2 are fitted respectively on the registration projections 33a and 33b on the front face of the metal frame 3. Thus, the second printed board 2 is superposed on the first printed board 1 through the metal frame 3. Then, in this condition, as shown in FIG. 5a, the two resilient clamping members 4 are pressed against the opposite sides of this semi-assembly, respectively, so that the guide holes 4a and 4b in each resilient clamping member 4 are fitted respectively on the associated retaining projections 34a and 34b on the metal frame 3. The opposite side portions of each resilient clamping member 4 are bent inwardly into a generally V-shaped, and further, the resilient clamping member 4 is curved slightly inwardly in its entirely. Therefore, each resilient clamping member 4 can be easily pressed onto the first and second printed boards 1 and 2 between which the metal frame 3 is interposed so as to clam the same, and the two resilient clamping members 4 can firmly join or connect the first and second printed board 1 and 2 and the metal frame 3 together. As a result, the printed board assembly 5 is assembled as shown in FIG. 5b. In this condition, the edge surface of the earth portion 14 of the first printed board 1 is held in contact with the edge surface of the wall portion 35 of the metal frame 3, and the edge surface of the earth portion 26 of the second printed board 2 is held in contact with the edge surface of the wall portion 31 of the metal frame 3. As a result, that side of the first printed board 1 having the electronic parts mounted thereon is closed or sealed by the back face of the metal frame 3 and the wall portion 35, and also that side of the second printed board 2 having the electronic parts mounted thereon is closed or sealed by the front face of the metal frame 3 and the wall portion 31. Therefore, these electronic parts can be easily shielded with the simple construction.
Next, the connection of the casing cover 8 to the casing body 7 will now be described. As shown in FIG. 6a, the casing body 7 has a U-like cross-sectional shape, and a plurality of retaining pawls 7a, 7b are formed integrally on the edge of each of opposite side walls thereof, and are spaced from one another along this side wall. On the other hand, retaining holes 8a and 8b are formed in those portions facing respectively to the retaining pawls 7a and 7b, as shown in FIG. 6c. With this arrangement, when the retaining pawls 7a and 7b on the casing body 7 are forced into the respective retaining holes 8a and 8b in the casing cover 8, a slanting surface of each retaining pawl 7a, 7b is pressed against an edge of the associated retaining hole 8a, 8b, so that the retaining pawl 7a, 7b are flexed inwardly, and then when recesses 7c, 7d immediately adjacent to the retaining pawl 7a, 7b are brought into the retaining holes 8a, 8b, the retaining pawls 7a, 7b are elastically restored to be locked in the associated retaining holes 8a, 8b, so that the casing body 7 and the casing cover 8 are easily connected together. For disconnecting the casing body 7 and the casing cover 8 from each other, the casing body 7 is pulled away from the casing cover 8 while pressing the opposite side walls of the casing body 7 toward each other (see FIG. 6b), so that the casing body 7 can be easily disconnected from the casing cover 8. Reference numerals 7e and 7f denote the retaining recesses for holding the printed board assembly.
Therefore, the printed board assembly 5 assembled in the manner shown in FIG. 5 is placed on the casing cover 8, and the dial button sheet 6 is placed on the printed board assembly 5. Next, the casing body 7 is put on the casing cover 8 to cover the printed board assembly 5 and the dial button sheet 6, and is pressed against the casing cover 8 so that the retaining pawls 7a and 7b are forced into the respective retaining holes 8a and 8b, and also the retaining projections 34a and 34b on the metal frame 3 are engaged in the respective retaining recesses 7e and 7f in the casing body 7 thereby to firmly hold the printed board assembly 5. Thus, the entire electronic equipment device can be easily assembled without the use of any screw.
As described above, the electronic equipment device comprises the first and second printed boards each having the associated electronic parts mounted thereon, the electrically-conductive frame interposed between the first and second printed boards to sealingly accommodate the electronic parts, mounted on the two printed boards so as to shield the electronic parts, and the resilient clamping members pressing the two printed boards against the frame to electrically connect the two printed boards to the frame. The radio transceiver portion is mounted on the first printed board, and the control circuit portion is mounted on the second printed board, and the frame is interposed between the first and second printed boards with these electronic parts facing the frame, thereby to provide the semi-assembly, and the two resilient clamping members grasp or clamp opposite side portions of this semi-assembly, respectively, to form the earth connection, so that the radio transceiver portion and the control circuit portion are shielded with the simple construction. Since the assembling is effected by the use of the resilient clamping members, the resultant assembly is mechanically rigid, and will not be twisted or deformed, and further, the number of the component parts, as well as time and labor required for assembling and disassembling the electronic equipment device, can be reduced. | There is disclosed an electronic equipment device. A pair of first and second printed boards are superposed with an electrically-conductive shield frame interposed therebetween in such a manner that those faces of the two printed boards having associated electronic parts mounted thereon are faced to each other. The shield frame has an integral peripheral wall extending over an entire peripheral edge thereof. This peripheral wall surrounds the electronic parts mounted on each of the two printed boards to achieve a shielding effect. Right and left sides of the stack of the two printed boards and the shield frame interposed therebetween are clamped respectively by a pair of resilient clamping members of a U-shaped cross-section to thereby provide a unitary assembly. These resilient clamping members cause earth portions of the first and second printed boards to be electrically connected to the shield frame. Finally, the above stack is housed in a casing body, thus completing the assembling of the electronic equipment device. | 7 |
BACKGROUND OF THE INVENTION
This invention relates to hand tools and more particularly, to hand tools for removing sprinkler heads from underground sprinkling systems.
In the past, sprinkler head removal involved the cutting of the turf encircling the sprinkler head, and the grasping and rotation of the sprinkler head canister to remove it from the associated riser of the underground watering system. Many times, the riser will remain connected to the sprinkler head canister, and separate from the system at a point below the riser pipe.
As the sprinkler head and/or sprinkler head and riser pipe were removed from the underground watering system, loose soil fragments and rocks would fall down around and into the piping system contaminating and plugging the piping system, including other risers and sprinkler heads on the line.
Before repair and/or replacement of the sprinkler head components, the piping system would have to be purged, usually involving at least two servicemen to manipulate the watering system. Such repair was not only time consuming, but required unnecessary cleanup effort.
DESCRIPTION OF THE PRIOR ART
The only known prior art is a hand operated bulb planter advertised and sold by Ames of Parkersburg, W. Va.
SUMMARY OF THE INVENTION
In accordance with the invention disclosed and claimed herein, a new tool is provided which is rotated when hand held to dig into the ground and surround the sprinkler head canister, and in so doing, compress the ground around the canister in the tool causing the tool to firmly grasp the canister so that it may be threadedly disconnected from the associated riser pipe.
It is, therefore, one object of this invention to provide a new hand held tool for removing sprinkler head canisters and/or riser pipes from an associated underground watering system.
Another object of this invention is to provide a new tool which compresses the ground in the tool when it surrounds the sprinkler head canister, causing the tool to tightly grip the canister so that it may be threadedly disengaged and removed from the associated underground watering system without creating loose soil fragments which fall around or in the watering system when the canister is removed from the ground.
A still further object of this invention is to provide a new tool which may be inexpensive to manufacture and sold to the trade.
Further objects and advantages of the invention will become apparent as the following description proceeds and the features of novelty which characterize this invention will be pointed out with particularity in the claims annexed to and forming a part of this specification.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention may be more readily described by reference to the accompanying drawings in which:
FIG. 1 is a perspective view of a hand held tool for removing sprinkler head and/or riser pipes from associated underground watering systems and embodying the invention;
FIG. 2 is a cross-sectional view of FIG. 1 taken along the line 2--2;
FIG. 3 is a cross-sectional view of FIG. 1 taken along the line 3--3;
FIG. 4 is a partial perspective view of the tool shown in FIG. 1 illustrating how it may be forced into the ground around a sprinkler head canister;
FIG. 5 is a partial cross-sectional view of the tool shown in FIG. 1 illustrating the gripping indentation within the tool;
FIG. 6 is a cross-sectional view of FIG. 5 taken along the line 6--6;
FIG. 7 is a partial view of a modification of the tool shown in FIGS. 1-6 wherein the gripping indentation comprises a plurality of circularly aligned spaced sections;
FIG. 8 is a cross-sectional view of FIG. 7 taken along the line 8--8; and
FIGS. 9A-9C diagrammatically illustrate three steps in the removal of a sprinkler head canister from the associated riser pipe of an underground watering system.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring more particularly to the drawings by characters of reference, FIGS. 1-3 disclose a tool 10 for removing sprinkler heads and/or riser pipes from an underground watering system comprising a hollow tapered coneshaped shell or housing 11 of approximately four to six inches long and having approximately a three inch diameter at its wide end and a two and one-quarter inch diameter at its narrow end. The narrow end is serrated along its edge and is provided at its other end 13 with outwardly extending flanges 14 and 15 that are interconnected at their free ends 16 and 17 by a hollow interconnecting cylinder 18 forming a handle 19. Cylinder 18 is provided for receiving axially therein a short rod 20 which serves as an extension of handle 19.
At a point substantially midway of its length, housing 11 is provided with a ring or flange 21 which is mounted to extend radially inwardly of the inside periphery 22 of housing 11 a short predetermined distance, such as 1/4 to 5/8 of an inch.
As shown in FIG. 4, tool 10 is placed around a canister 23 of a sprinkler head 23A with its serrated end 12 extending into turf 24 of ground 24A. Sprinkler head 23A is part of an associated sprinkling system 24B. The tool is then rotated and twisted in both directions, as shown by arrows 25' and 26', around sprinkler head 23 as it is being pressed into the turf and ground causing the tool to cut through turf 24 and the ground underneath it so as to surround the sprinkler head.
FIGS. 5 and 6 illustrate a modification of the hand tool showing in FIGS. 1-4 having the same features as tool 10, except in tool 25, ring 21 of tool 10 is replaced by an indentation 26 formed in and around its housing 27. This indentation forms a ridge 28 inside of housing 27 which functions in the same manner as ring 21 of tool 10.
FIGS. 7 and 8 disclose a still further modification of tools 10 and 25 wherein a plurality of spaced indentations 29A-29D are formed in the outer surface of housing 30 of tool 31 to form a plurality of ridge sections extending inwardly of the periphery of the inside surface 32 of housing 30 to function in the same manner as ring 21 of tool 10. Although the ridge sections are shown in a circular arrangement, they may be axially spaced from each other along the length of the tool and still fall within the scope of this invention.
FIGS. 9A-9C disclose the steps in using the tools, such as tool 10, which is first pressed and rotated into and through the turf and ground around a faulty sprinkler head 23 until it substantially reaches the place around the sprinkler head shown in FIGS. 9A. It should be noted that rod 20 may be removed from cylinder 18 so that the tool can be easily rotated by one hand of the user in poor clearance areas, such as against walls. Dowel pin or rod 20 can be inserted into the handle formed by cylinder 18 for two-handed operation, one on each side of cylinder 18 for application of more pressure on the tool when encountering rocky or hardpan soils.
The serrated end 12 of tool 10 readily cuts through the turf and ground beneath it as it is rotated and twisted and pushed into the soil around the complete sprinkler head, until the top or cap of the sprinkler head is substantially flush with the opening at end 13 of the tool.
As the tool moves down through the soil around the sprinkler head, the cone-shaped opening inside housing 11 of tool 10, as well as the ridges formed inside of tools 25 and 31, aid in containing and compressing the soil inside of the tool around the sprinkler head and, particularly under ring 21 and against sprinkler head 23. As soil is forced between the tool's lower opening and the sprinkler head, it will continue upward until the restricted clearance of the ring will prevent most of it from traveling further upwardly into the tool.
At the same time, soil at the junction of the riser pipe 35 and the canister 23 of the sprinkler head 23A is compressed downwardly due to the inner ring 21, i.e., the initial purpose of the ring. Because of the compression of the soil in the riser pipe area, the riser will remain secured to the sprinkling system below, thereby enabling separation at the junction of the riser pipe 35 and canister 23 of the sprinkler head, rather than any coupling of the sprinkling system further below the sprinkler head. This is one of the major benefits of the tool to obtain a clean separation at the required junction.
Further, any soil that squeezed through ring 21 on downward compression of tool 10 comes into contact with the underside 33 of cap 34 of the sprinkler head which is slightly larger in diameter than canister 23 of sprinkler head 23A.
Still further, upon insertion of tool 10 into the ground, more of the wet compressed soil in housing 11 will flow to one side of the tool, thereby tilling tool to one side of the sprinkler head, as shown in FIGS. 9A and 9B.
It should be noted, that the usual condition of an irrigated lawn area is that the soil is moist or wet. This results in the soil being cohesive and aids in its compaction during tool use.
The unavoidable tilting of the tool upon insertion may be attributed to the soil conditions between the tool and the sprinkler head following the path of least resistance along with the operator being unable to maneuver the tool exactly parallel with the axis of the sprinkler head.
The operator then applies pressure to handle 19 in the direction of tilt and then pulls the tool up slightly while still applying pressure in the direction of the till, as shown by the dash lines in FIG. 9A. This will compress the soil between the underside of cap 33 and the top of ring 21 on one side of the tool. The continued pressure and upward pull will be applied through the unthreading procedure of the sprinkler head.
This is the upward locking motion by the operator that will apply torque from the tool's body 11 and ring 21 through the compressed soil to the sprinkler head and its cap 34, enabling the tool to grip the sprinkler head firmly in the tool and prevent further upward movement of the tool out of the ground until the sprinkler head is unthreaded.
The tool handle 19 is now turned counterclockwise to remove the sprinkler head 23A from its threaded connection with the top end of riser pipe 35. The tool containing the sprinkler head is then removed from the hole in the ground.
Because the soil is compressed below the opening in the top of the riser pipe 35, the soil outside of the tool has been compressed and the layer of soil and sod around the sprinkler head being contained in the tool, there is very little chance of soil fragments or rocks falling into the associated riser pipe opening.
With the sprinkler head removed in this manner by tool 10, an open work area in the hole is provided enabling visual inspection of the riser pipe and most important, exposure of the threads on the top of the riser pipe, thereby assuring easy access thereto for replacement of a repaired or replacement sprinkler head.
Upon removal of the tool and sprinkler head from the ground, the head is pushed by operator's fingers from the narrow end 12 of the tool up through the soil layer in the tool and taken out of its upper larger open end 13, as shown in FIG. 9C.
The layer of soil and sod remaining in the tool, as shown in FIG. 9C, can be peeled out with the operator's fingers and pressed around the repaired or replacement sprinkler head in the hole to secure it firmly back in the lawn area. With the use of this tool, there is very little evidence of a sprinkler repair having been made.
The tool disclosed may be made in various sizes to fit and remove various sprinkler heads.
A further use of the tool disclosed is to remove only the turf and sod around the sprinkler head by twisting and cutting into the material with the serrated end of the tool without penetrating deeper into the ground around the sprinkler head.
After cutting a doughnut-shaped piece of sod around the head, the grass ring can be removed by prying with the fingers of the operator. This action will enable the sprinkler head to be inspected or any grass restriction removed for better spray coverage.
Although but a few embodiments of the invention have been illustrated and described, 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. | A hand held tool for rotating and twisting as it is forced into the turf and ground over and around a part of a watering system such as a sprinkler head, and employing a ridge at least partially around its inside periphery which traps and compresses the ground in the tool, causing the tool to interlock with the sprinkler head so that the sprinkler head can be threadedly removed from a riser pipe by rotation of the tool. | 1 |
FIELD OF THE INVENTION
Botanical classification/cultivar designation: Phalaenopsis Orchid cultivar SOGO F1982.
BACKGROUND OF THE INVENTION
The present invention comprises a new and distinct cultivar of Phalaenopsis Orchid, a bigeneric hybrid of Phalaenopsis×Phalaenopsis of the family Orchidaceae, and hereinafter referred to as the cultivar name, SOGO F1982. The genus Phalaenopsis is a member of the family Orchidaceae.
Phalaenopsis comprise a group of bigeneric hybrids generally intermediate in character between the parent genera, which are suitable for cultivation in the home or greenhouse. The parent genera of Phalaenopsis are predominantly epiphytic or rock dwelling, and are native to tropical Asia, Malay Archipelago, and Oceania. The species typically have 2-ranked fleshy oblong or elliptic leaves affixed to a short central stem (monopodial growth), which vary in size from 5 to 8 inches to over 2 feet. The leaves may be entirely green or mottled with silver grey.
Phalaenopsis orchid, often referred to ‘Moth Orchids’ in the horticultural trade, are frequently used to furnish cut flowers for the florist trade, or sold as flowering potted plants for home or interiorscape.
Phalaenopsis produce upright racemes, often with many showy flowers, which open in succession beginning with the lowermost. The flowers possess three sepals, and three petals, the lateral ones being alike. The lowermost petal, called the labellum, is three lobed and is often more brightly colored than other flower segments. Flower colors are frequently various shades of pink, white and yellow.
Phalaenopsis orchids are typically propagated from seeds. However, Phalaenopsis is capable of being asexually reproduced from offshoots, which frequently arise from the lower bracts of the inflorescence. The resulting plants are detached from the mother plant and may be planted in a suitable substrate.
‘SOGO F1982’ is a product of a planned breeding program conducted by the inventor in Kaohsiung County, Taiwan, R.O.C. The objective of the breeding program is to create new uniform pot-type Phalaenopsis Orchid cultivars having attractive flower coloration. The inventor has addressed himself to the Orchid breeding since 1985.
‘SOGO F1982’ was discovered by the inventor from within the progeny of a cross-pollination of one Phalaenopsis Orchid, Phal. ‘Brother Peterstar’ and one Phalaenopsis Orchid, Phal. ‘Brother Sara Gold’ on February 1999, in a controlled environment in Kaohsiung County, Taiwan, R.O.C.
Asexual propagation by tissue culture in a laboratory in Pingdong County, Taiwan, R.O.C. has been used to increase the number of plants for evaluation and has demonstrated in a controlled environment in Kaohsiung County, Taiwan, R.O.C. that the unique combination of characteristics as herein disclosed for the new Phalaenopsis Orchid are firmly fixed and are retained through successive generations of asexual reproduction.
SUMMARY OF THE INVENTION
The following traits have been repeatedly observed and are determined to be basic characteristics of ‘SOGO F1982’ which in combination distinguish this Phalaenopsis Orchid as a new and distinct cultivar:
1. Abundant purple dapple overlaid with yellow toward pink base and the pink with white colored labellum. 2. Freely flowering habit. 3. Upright, freely branching and sturdy flowering stems. 4. Excellent postproduction longevity.
Plants of ‘SOGO F1982’ differ primarily from plants of the parent cultivars in flower color. The main color of the petals of Phal. Brother Peterstar is RHS 21A and the pattern color thereof is RHS 34A. The main color of the petals of Phal. Brother Sara Gold is RHS 21C and the pattern color thereof is RHS 34A.
Currently, there is no commercial cultivar to which ‘SOGO F1982’ can be meaningfully compared.
BRIEF DESCRIPTION OF THE DRAWINGS
The accompanied photographic illustrations show typical plant and flower characteristics of ‘SOGO F1982’ with colors being as true as possible with illustrations of this type.
FIG. 1 is a side view of a plant of ‘SOGO F1982’ flowering in the pot of 13 cm.
FIG. 2 is a close-up view showing the characteristics of the flower.
FIG. 3 is a close-up view showing the characteristics of the leaf.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
‘SOGO F1982’ has not been observed under all possible environmental conditions. The phenotype may vary significantly with variations in environment such as temperature, light intensity, fertilization and day length without any change in the genotype.
The observations and measurements describe plants grown in Kaohsiung County, Taiwan, R.O.C. under the conditions, which approximate those generally used in commercial practice.
In the following description, color references are made to The Royal Horticultural Society (R.H.S.) Color Chart.
Plants used for the aforementioned photographs and the following detailed botanical description were 18 months in maturity and grown in the pots of 13 cm, in a controlled greenhouse with day-night temperature around 25–18 degree Celsius, and light intensity between 15,000˜20,000 lux natural light, in Kaohsiung County, Taiwan, R.O.C.
Origin: Seedling from a cross of the selected Phalaenopsis orchids as described above. Classification: Phalaenopsis hybrid cv. ‘SOGO F1982’. Propagation: Asexual propagation by tissue culture. Plant description:
Plant height.— Soil level to top of foliar plane is about 10 to 15 cm. Plant height.— Soil level to top of inflorescences is about 35 to 45 cm. Plant diameter.— Is about 20 to 25 cm. Growth habit.— Compact, small, dark-green leaves and a relatively short raceme. Flowers per stem.— Approximately 5 to 15.
Foliage description:
Quantity.— Approximately 6 to 8 leaves are produced before flowering. Size of leaf.— 10 to 15 cm long and 7 to 9 cm wide. Shape.— The leaf blade is short and elliptic with a cuneate base and an obtuse tip. The leaf blade is leathery and thick. The middle vein protrudes, while the other veins are not visible in the thick leaf blade. Attitude.— Horizontal and on two sides parallel. Color.— Upper surface: Dark-green, RHS 137B. Lower surface: Light-green, RHS 137C.
Inflorescence description:
Flower type and habit.— Single zygomorphic flowers arranged in racemes. Flowers are roughly pentagonal in shape. Flowering stems upright, freely branching and sturdy. Plants freely flowering; plants typically produce one to three branched flowering stems with at least 4 to 12 flowers each. Fragrance.— No fragrance. Natural flowering season.— From February to April in the southern part of Taiwan. The flower spikes can be induced under the controlled environment, of which day-night temperature at 25–18 degree C. for 2 weeks. Post - production longevity.— Plants of ‘SOGO F1982’ maintain good leaf and flower substance for about three to six months on the plant under interior environmental conditions. Lastingness of cut flowers has not been observed. Inflorescence length.— About 18 to 23 cm. Inflorescence diameter.— About 35 to 40 cm. General impressions of petals and sepals.— Horizontal elliptical in shape, about 5.3 cm of flower width in front view. Sepals.— There are 3 sepals which are fleshy and glabrous in texture, with straight margins and in elliptical shape, about 2.6 cm in length and 1.9 cm in diameter. The main color of dorsal sepal is RHS N144B, the pattern color of dorsal sepal is 60C. The main color of lateral sepals is RHS N144B, the pattern color of lateral sepal is 59A. Petals.— There are 2 open petals which are fleshy and glabrous in texture, with margins weakly undulate and in elliptical shape, about 2.5 cm in length and 2.3 cm in diameter. The main color of petals is RHS 7A, the pattern color of petals is 60C. Labellum ( lip ).—The lip whiskers are absent, shape of apical lobe is ovate, approximately 1.7 cm long and 1.2 cm wide. The base color of apical lobe is RHS 59B, the tip color of apical lobe is RHS N74A. Peduncles.— Length about 35 to 45 cm, diameter about 9 mm, upright, strong and sturdy, with smooth and glabrous texture. Color is RHS 137C. Pedicels.— Length about 3.6 cm, diameter about 3 mm. Aspect about 60.degree from vertical. Strong, with a texture of smooth and glabrous. Color RHS 145D, towards the base, overlaid with RHS 144A.
Reproductive organs: The stamens, style and stigmas are fused into a single, short structure called the column, possessing one terminal anther with pollen grains united into a pollinia, which are covered by an anther cap. The stigma is located under the column behind the pollinia. The ovary is inferior with three carpels present. The plant has not produced seed.
Column— Approximately 10 mm long and 5 mm wide, RHS N78C. Pollinia.— Two, about 1 mm oval masses of pollen present, RHS 17A. Ovary.— 5 to 7 mm long and 2.4 mm in diameter, RHS 75B. Roots: Fleshy, approximately 5 mm wide and green, RHS 191B.
Plant disease resistance/susceptibility: No specific resistance or susceptibility observed. General observations: Phalaenopsis ‘SOGO F1982’ produces two or more inflorescence with flowers having sepals and petals in the color of abundant purple dapple overlaid with yellow toward pink base. A pink white labellum. The inflorescence is strong, erect and sturdy, relatively short, and easily packaged for shipping. The plant grows very quickly to marketable size. ‘SOGO F1982’ can be economically propagated via tissue culture. | A new and distinct cultivar of Phalaenopsis plant named ‘SOGO F1982’, comprises its flowers of abundant purple dapple overlaid with yellow toward pink base and the pink with white labellum, freely flowering habit, upright, freely branching and sturdy flowering stems, and the excellent postproduction longevity. | 0 |
CROSS-REFERENCE TO A RELATED PATENT APPLICATION
This patent application is a Continuation of U.S. patent application Ser. No. 08/227,937, filed on Apr. 15, 1994, which issued as U.S. Pat. No. 5,471,033, on Nov. 28, 1995.
FIELD OF THE INVENTION
This invention relates generally to a process and apparatus for contamination-free processing of semiconductor parts. More specifically, this invention relates to a process and apparatus for contamination-free processing of semiconductor parts in an oven or a furnace. This invention also relates to a process and apparatus for contamination-free processing of semiconductor parts in a furnace, such as a belt type furnace that sequentially stops the belt at the vicinity of at least one heating or cooling unit to heat or cool the part.
BACKGROUND OF THE INVENTION
For many years the electronics or semi-conductor industry has been using various types of ovens and furnaces for high volume heating and/or cooling applications. In the oven and furnace industry many inventions have occurred. However, most of them have been directed to innovations in either cooling or heating of the parts that are being processed.
U.S. Pat. No. 4,554,437 (Wagner et al.) discloses a continuous speed belt type tunnel oven which allows a user to select different top and bottom temperatures within each of the plural cooking zones.
U.S. Pat. No. 4,693,211 (Ogami et al.) discloses a surface treatment apparatus, which is composed of a supporting die for holding a substrate thereon to heat and/or cool the substrate. A cover defines a treatment space over the entire surface of the substrate on the supporting die. Preferably, a heat-insulating housing could be outside the cover.
U.S. Pat. No. 4,886,954 (Yu et al.) discloses a hot wall diffusion furnace and a method for operating the furnace. Yu et al. disclose that the heating elements in the upper section of the furnace be connected to one circuit, and the heating elements of the lower section of the furnace be connected to a second circuit, and that each circuit be controlled in response to the temperature in that section, so that uniform temperature can be obtained in the processing chamber.
U.S. Pat. No. 4,903,754 (Hirscher) discloses a method and apparatus for the transmission heat to or from plate like object. The plate-like object, such as a Si wafer, is held on a back plate and inside a cover. This patent discloses both the heating and cooling of the plate-like object.
U.S. Pat. No. 4,950,870 (Mitsuhashi et al.) discloses a heat-treating apparatus having at least three heaters and the power to these heaters can be supplied from independent power sources so that the heating temperatures of the individual heaters can be freely adjusted. Additionally, the multiple heaters in the vertical furnace attain a uniform heat distribution throughout the heating zone.
U.S. Pat. No. 4,966,547 (Okuyama et al.) discloses a heat treatment method using a zoned tunnel furnace. The furnace has roller conveyer and each of the zones in the furnace walls are provided with electric resistance heating wires. The heaters in each zone are under programmed control, independent of the heaters in the other zones. Similarly, the roller conveyer in each zone can be driven independent of the roller conveyer in the other zones by programmable controllers.
U.S. Pat. No. 4,982,347 (Rackerby et al.) discloses a process and apparatus for producing temperature profiles in a workpiece as it passes through a belt furnace. Each of the heaters has their own separate thermostats, which enables the temperature of each heater to be separately set. Thus a workpiece can be subjected to a temperature profile which varies from heater to heater along the passageway.
U.S. Pat. No. 5,054,418 (Thompson et al.) discloses a device for holding wafers of semi-conducting materials during thermal processing or coating, where the device is a cage boat having removable slats.
The parts or products using conventional furnaces and ovens have changed over time. Some of the parts have been getting larger and others are getting smaller, and still other require more stringent processing controls. Therefore, it has become increasingly difficult to do the same type of processing on the parts, as done by the ovens and furnaces known in the art.
For some parts the thermal mass or thermal weight resists being heated quickly, and therefore they may have to be processed for a longer period. Another factor is that newer and different materials are being used to make these parts, and these newer materials require different heating regimes. These issues are further compounded by the fact that now closer temperature control and lower intra-part gradients are being required by the electronics industry.
The manufacturers of conventional ovens and furnaces have made quite a few upgrades to their system in response to the industrial needs. Some upgrades include providing better and more efficient gas flows. Others have provided improved zone separation. And, still others are providing better cooling in the cool down section. Most of these changes are required because the parts or products are less tolerant to thermal process irregularities and the resultant mechanical stresses, etc.
Another problem faced in the use of conventional ovens or furnaces is that when flux or similar contaminants are used in a conventional oven or furnace they get deposited on the walls of the furnace creating a contamination problem for the furnace as well as the parts that are being processed in the furnace. Flux and similar contaminants results from many processes, such as a soldering process, and therefore cannot be eliminated. Similarly, there are other solvents which evaporate from the surface of the part, as the part is being heated, and they enter the flow of the gases in the furnace, flowing from the hotter end or area to a colder area. This causes the vaporized solvents and similar other material to condense on cooler furnace areas or parts and this collects as contamination.
For an application, such as chip join, the operation is characterized by loading many parts on a belt, followed by continuous movement of the belt through the furnace's heating and/or cooling areas, and thus it is not very practical to stop and clean the furnace for a different part and/or a different process.
Therefore, during a typical high volume heating and/or cooling applications care must be taken to prevent the parts being processed from being contaminated with contaminants that are inside the furnace, and that the contamination be kept to the minimum.
For the above-mentioned reasons, parts cannot always be processed within specification using the conventional ovens or furnaces, and therefore there is a need for improvement in the furnace and oven industry.
The above-mentioned and other problems have been overcome by the novel apparatus and the process of this invention.
BRIEF SUMMARY OF THE INVENTION
In one aspect the invention comprises a process for processing a part in a contaminating environment wherein said part is protected from said contamination, comprising the steps of:
(a) placing said part on a part carrier in a first environment,
(b) placing a cover over said part carrier and enveloping said part so as to form a boat,
(c) removing said boat from said first environment,
(d) placing said boat in a second, more contaminating, environment and processing said part.
In another aspect the invention comprises an apparatus for processing at least one part comprising a covered boat enveloping said part and having a first environment while said apparatus having a second more contaminating environment, wherein said covered boat is placed inside said apparatus and further comprising at least one means for processing said part.
PURPOSES OF THE INVENTION
One purpose of this invention is to provide a process that is very economical.
Another purpose of the invention is to provide a process that is easily adaptable to the existing ovens and furnaces.
Still another purpose of this invention is to provide a system that transports the parts through a contaminating environment without contaminating the part.
Yet another purpose of this invention is to process the part such that the part is itself in a less contaminated environment than its surroundings.
BRIEF DESCRIPTION OF THE DRAWINGS
The features of the invention believed to be novel and the elements characteristic of the invention are set forth with particularity in the appended claims. The figures are for illustration purposes only and are not drawn to scale. The invention may be best understood by the description which follows, taken in conjunction with the accompanying drawings in which:
FIG. 1, is a perspective view of a preferred embodiment of the present invention.
FIG. 2, is a perspective view showing another embodiment of the present invention.
FIG. 3A, is a perspective view showing yet another embodiment of the present invention.
FIG. 3B, is a sectional view taken along section 3B--3B of FIG. 3A.
FIG. 4, is a cross-sectional view of still another embodiment of the present invention.
FIG. 5, is a cross-sectional view of still yet another embodiment of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
The preferred embodiment of the invention is illustrated in FIG. 1, where a part or a substrate 10, to be processed is placed on a base 12, and is protected from the environment by a cover 14. The base 12, having an upper surface 18, is typically made from quartz, glass, metal, etc. Similarly, it is preferred that the cover 14, having peripheral base edge 28, be also made from quartz, glass, metal, to name a few.
In a typical application the substrate 10, is placed on the upper surface 18, of the base 12, for example, in a Class 10 clean room, and then the cover 14, is subsequently placed to protect the substrate 10, in the same Class 10 clean room. A Class 10 clean room, for example, is a room or area where there are less than 10 particles of not greater than 0.3 micron particle size per cubic foot of air. This way the contamination inside the cover is Class 10, and there is no reason to create a vacuum inside the cover 14, to keep the area inside the cover 14, and over and around the substrate 10, contamination free. The base 12, along with the cover 14, will be referred to as a parts carrier or boat 20.
For some applications it may be necessary to create a vacuum or extract certain contaminants out of under the cover 14, and keep the substrate 10, in a contamination free environment. This can be done as illustrated in FIG. 2, where a boat 40, having a cover 24, has at least one vent or plug 16, through which the contaminating gases and/or particles could be extracted. Of course this vent or plug 16, could be on the top of the cover 24, or could be a part of the base 12. The vent or plug 16, could also be used to prevent the creation of a pressure differential between inside and outside of the boat.
FIG. 2, also illustrates that the substrate 10, could also be placed on a substrate or part pedestal or support 22. The substrate pedestal 22, allows the part or substrate 10, to be processed without the need to have the substrate 10, itself be physically moved. For some applications the substrate 10, could be secured to the substrate pedestal 22, by means well known in the art, such as, screws, bolts, clamps, etc.
FIG. 3A, is a perspective view showing yet another embodiment of the present invention, while FIG. 3B is a sectional view taken along section 3B--3B of FIG. 3A. A boat or parts carrier 60, has a base 32, having a groove or a trench or channel 30, to accommodate the peripheral base edge 28, of the cover 14. The base edge 28, could have rectangular-type shape or circular-type shape or polygonal-type shape or a triangular-type shape, to name a few. Of course the trench or channel 30, in the base 32, should have a shape complementary to that of the base edge 28, to provide the maximum seal or contamination free environment to the part 10.
For some applications it may be necessary to put a seal or similar such media between the base edge 28, and the upper surface 18, of the base 12 or 32. Typical seals that are used in the industry are seals made from silicon or polymers, to name a few.
FIG. 4, illustrates a cross-sectional view of a boat or parts carrier 80, which is still another embodiment of the present invention. The boat 80, typically has a pan-shaped base 42, having side-walls 44. The part 10, to be processed could be placed on a support or pedestal 46, having a plurality of posts or stand-offs 48. Cover 54, having ledge 56, is then used to provide a cover for the part 10, and posts or stand-offs 45, typically, separate the cover 54, from the base 42. For some applications, the stand-offs 45 and/or 48, could be made from material that allows the movement of fluid through it. This movement of fluid, such as air, of course will prevent or reduce any pressure differential that might exist between the inside and outside of the boat 80.
FIG. 5, is a cross-sectional view of still yet another embodiment of the present invention showing a boat or parts carrier 100. The boat 100, has a pan-shaped base 62, having side-walls 64. The base 62 and the side-walls 64, could have one or more electrical implants, such as, resistance thermal heater 65, to provide local thermal heating to the part 10, which may be on a plurality of posts or stand-offs 48. A cover 74, having ledge 76, could also have at least one electrical implant or resistance thermal heater 75, to provide local thermal heating to the part 10. The boat 100, could also have one or more breathers or vents 66, to allow for the part to "breathe" or to prevent a pressure differential from occurring inside the boat 100. In some cases the boat 100, could of course itself be placed inside an oven for further processing of the part 10.
The boat 20, 40, 60 or 80, along with the substrate 10, is typically placed in an oven or furnace or a cooling environment and the processing of the part 10, continues.
As will be appreciated that now, for example, the boat 20, can be placed in an oven or a furnace (not shown) that has, for example, a Class 100 or Class 1000 or more environment but the part 10, being in the boat 20, will not be exposed to the outside contamination, and will only see the cleaner, for example, Class 10, environment.
The boat or parts carrier 20, 40, 60 or 80, could also be placed on a sequential belt type furnace, as disclosed in U.S. patent application Ser. No. 07/920,948, entitled "Sequential Step Belt Furnace With Individual Concentric Heating Elements", assigned to the assignee of the instant patent application and the disclosure of which is incorporated herein by reference, and the part 10, could be processed without being contaminated by carrier gasses that might exist in a belt type furnace.
Similarly, the boat or parts carrier 20, 40, 60, 80 or 100, could also be placed on a sequential belt type furnace, as disclosed in U.S. patent application Ser. No. 08/218,105, filed on Mar. 25, 1994, now U.S. Pat. No. 5,421,723, entitled "Sequential Step Belt Furnace With Individual Concentric Cooling Elements" assigned to the assignee of the instant patent application and the disclosure of which is incorporated herein by reference, and the part 10, could be processed without being contaminated by the contaminants that might exist in the furnace.
The part 10, could be an I. C. (Integrated Circuit) chip or a semiconductor substrate or a semiconductor module, or similar such product.
It has been found that the parts 10, described in this invention, could be large parts, such as ceramic substrates which are typically about 100 mm by 100 mm to about 20 mm by 20 mm or smaller parts, such as semiconductor chips which are typically about 10 mm by 10 mm.
The heating or "cooling" is typically provided to the boat 20, 40, 60, 80 or 100, and in-turn to the part 10, by one or more of the upper, lower or side heating or cooling units in a furnace.
If a sequential belt type furnace is used then the boat 20, 40, 60 or 80, is typically accelerated, and then decelerates, and the part 10, is placed typically in the center of the heating or cooling zone. Of course, using a computer or a controller one could program or control or monitor the transit or soak times or the belt speeds, etc.
Using the inventive boat 20, 40, 60, 80 or 100, the contaminating gases or particles or evaporated flux that may exist in an oven or a furnace, never gets an opportunity to condense on the surface of the part.
As one can see that the process and apparatus of this invention provides a substantial improvement over the state of the art.
This inventive furnace can be used for a variety of processes, for example, pin brazing process, chip join process, C4 (Controlled Collapse Chip Connection) bonding, to name a few. (C4 and Controlled Collapse Chip Connection are Trademarks of IBM Corporation, Armonk, N.Y., USA.)
The thermally conductive closed boat or container of this invention provides isolation of the product and shields it from contamination that is generated, such as from the surrounding environment, processing machinery, etc.
The invention also provides a mean to uniformly heat the part while shielding it from the contaminants.
It has also been discovered that the boat or parts carrier having a limited number of holes or openings or vents or material that allow for limited amount of fluid flow does not have any major adverse affect on the part being processed. As a matter of fact the amount of contaminants in a fully sealed boat was not any lower than a similar boat with limited vents that allowed for limited fluid flow.
EXAMPLES
The following examples are intended to further illustrate the invention and are not intended to limit the scope of the invention in any manner.
Example 1
A large sized semiconductor substrate A, was placed inside a contamination control box and then covered. The covered container was then placed inside a Blue M oven and the substrate A was baked at approximately 400° C. After the processing of substrate A, a surface particle count was made and it was found that the surface of substrate A, had 1,228 particles. A similar substrate B, was also processed in the same Blue M oven under the same processing conditions, but on an open boat, and upon inspection a total of 2,312 particles were counted on the surface of substrate B. This is an increase of 1,084 particles after the baking step.
Example 2
A medium sized semiconductor substrate C, was placed inside a contamination control box and then covered. The covered container was then placed inside a Blue M oven and the substrate C, was baked at approximately 400° Centigrade. After the processing of substrate C, a surface particle count was made and it was found that the surface of substrate C, had 221 particles. A similar substrate D, was also processed in the same Blue M oven under the same processing conditions, but on an open boat, and upon inspection a total of 333 particles were counted on the surface of substrate D. This is an increase of 112 particles after the baking step. The surface of both parts C and D, had a coating of a layer of polyimide.
Example 3
A small sized semiconductor substrate E, was placed inside a contamination control box and then covered. The covered container was then placed inside a Blue M oven and the substrate E, was baked at approximately 400° Centigrade. After the processing of substrate E, a surface particle count was made and it was found that the surface of substrate E, had 190 particles. A similar substrate F, was also processed in the same Blue M oven under the same processing conditions, but on an open boat, and upon inspection a total of 257 particles were counted on the surface of substrate F. This is an increase of 67 particles after the baking step. The surface of both parts E and F, had a coating of a layer of approximately 200 angstroms of chromium.
While the present invention has been particularly described, in conjunction with a specific preferred embodiment, it is evident that many alternatives, modifications and variations will be apparent to those skilled in the art in light of the foregoing description. It is therefore contemplated that the appended claims will embrace any such alternatives, modifications and variations as falling within the true scope and spirit of the present invention. | This invention relates generally to a process and apparatus for contamination-free processing of semiconductor parts. More specifically, this invention relates to a process and apparatus for contamination-free processing of semiconductor parts in an oven or a furnace. This invention also relates to a process and apparatus for contamination-free processing of semiconductor parts in a furnace, such as a belt type furnace that sequentially stops the belt at the vicinity of at least one heating or cooling unit to heat or cool the part. | 2 |
[0001] This application claims priority from copending Provisional Application Nos. 60/527,928 filed Dec. 8, 2003 and 60/584,823 filed Jul. 1, 2004 the entire disclosures of which are hereby incorporated by reference.
FIELD OF THE INVENTION
[0002] The present invention relates to novel oxazole derivatives of tetracyclines which are useful as antibiotic agents and exhibit antibacterial activity against a wide spectrum of organisms including organisms which are resistant to tetracyclines and other antibiotics. This invention also relates to novel tetracycline intermediates useful for making the novel compounds and novel methods for producing the novel compounds and the intermediate compounds.
BACKGROUND OF THE INVENTION
[0003] Since 1947 a variety of tetracycline antibiotics have been synthesized and described for the treatment of infectious diseases in man and animals. Tetracyclines inhibit protein synthesis by binding to the 30S subunit of the bacterial ribosome preventing binding of aminoacyl RNA (Chopra, Handbook of Experimental Pharmacology, Vol. 78, 317-392, Springer-Verlag, 1985). Resistance to tetracyclines has emerged among many clinically important microorganisms which limit the utility of these antibiotics. There are two major mechanisms of bacterial resistance to tetracyclines: a) energy-dependent efflux of the antibiotic mediated by proteins located in the cytoplasmic membrane which prevents intracellular accumulation of tetracycline (S. B. Levy, et al., Antimicrob. Agents Chemotherapy 33, 1373-1374 (1989); and b) ribosomal protection mediated by a cytoplasmic protein which interacts with the ribosome such that tetracycline no longer binds or inhibits protein synthesis (A. A. Salyers, B. S. Speers and N. B. Shoemaker, Mol. Microbiol, 4:151-156, 1990). The efflux mechanism of resistance is encoded by resistance determinants designated tetA-tetL. They are common in many Gram-negative bacteria (resistance genes Class A-E), such as Enterobacteriaceae, Pseudomonas, Haemophilus and Aeromonas, and in Gram-positive bacteria (resistance genes Class K and L), such as Staphylococcus, Bacillus and Streptococcus. The ribosomal protection mechanism of resistance is encoded by resistance determinants designated TetM, N and O, and is common in Staphylococcus, Streptococcus, Campylobacter, Gardnerella, Haemophilus and Mycoplasma (A. A. Salyers, B. S. Speers and N. B. Shoemaker, Mol. Microbiol, 4:151-156 1990).
[0004] A particularly useful tetracycline compound is 7-(dimethylamino)-6-demethyl-6-deoxytetracycline, known as minocycline (see U.S. Pat. No. 3,148,212, U.S. Pat. No. RE 26,253 and U.S. Pat. No. 3,226,436 discussed below). However, strains harboring the tetB (efflux in gram-negative bacteria) mechanism, but not tetK (efflux in Staphylococcus) are resistant to minocycline. Also, strains carrying tetM (ribosomal protection) are resistant to minocycline. This invention describes the synthesis of novel tetracycline compounds which demonstrate significant in vitro and in vivo activity vs. tetracycline and minocycline susceptible strains and some tetracycline and minocycline resistant strains, that is, those harboring the tetM (ribosomal protection) resistance determinants.
[0005] Duggar, U.S. Pat. No. 2,482,055, discloses the preparation of Aureomycin.RTM. by fermentation which have antibacterial activity. Growich et al., U.S. Pat. No. 3,007,965, disclose improvements to the fermentation preparation. Beereboom et al., U.S. Pat. No. 3,043,875 discloses tetracycline derivatives Boothe et al., U.S. Pat. No. 3,148,212, reissued as U.S. Pat. No. RE 26,253, and Petisi et al., U.S. Pat. No. 3,226,436, discloses tetracycline derivatives which are useful for treating bacterial infections. Blackwood et al., U.S. Pat. No. 3,200,149 discloses tetracycline derivatives which possess microbiological activity. Petisi et al., U.S. Pat. No. 3,338,963 discloses tetracycline compounds which have broad-spectrum antibacterial activity. Bitha et al., U.S. Pat. No. 3,341,585 discloses tetracycline compounds which have broad-spectrum antibacterial activity. Shu, U.S. Pat. No. 3,360,557 discloses 9-hydroxytetracyclines which have been found to possess antibacterial activity. Zambrano, U.S. Pat. No. 3,360,561 discloses a process for preparing 9-nitrotetracyclines. Martell et al., U.S. Pat. No. 3,518,306 discloses tetracyclines which possess in vivo antibacterial activity.
[0006] In U.S. Pat. No. 5,021,407 a method of overcoming the resistance of tetracycline resistant bacteria is disclosed. The method involves utilizing a blocking agent compound in conjunction with a tetracycline type antibiotic. This patent does not disclose novel tetracycline compounds which themselves have activity against resistant organisms. Described in U.S. Pat. No. 5,494,903 are 7-substituted-9-substitutedamino-6-demethyl-6-deoxytetracyclines which have broad spectrum antibacterial activity.
[0007] In summary, none of the above patents teach or suggest the novel compounds of this application. In addition, none of the above patents teach or suggest novel tetracycline compounds of the invention having activity against tetracycline and minocycline resistant strains as well as strains which are normally susceptible to tetracyclines.
SUMMARY OF THE INVENTION
[0008] In accordance with the present invention, there is provided compounds represented by Formula (I);
[0000]
[0000] wherein:
X is selected from hydrogen, amino, NR 11 R 12 , alkyl of 1 to 12 carbon atoms optionally substituted, aryl of 6, 10 or 14 carbon atoms optionally substituted, vinyl optionally substituted, alkynyl of 2 to 12 carbon atoms optionally substituted and halogen;
A″ is a moiety selected from the group:
[0000]
[0000] R 11 and R 12 are each independently H or alkyl of 1 to 12 carbon atoms or
R 11 and R 12 when optionally taken together with the nitrogen atom to which each is attached form a 3 to 7 membered saturated hydrocarbon ring;
Y is selected from hydrogen, alkyl of 1 to 12 carbon atoms optionally substituted, aryl of 6, 10 or 14 carbon atoms optionally substituted, alkenyl of 2 to 12 carbon atoms optionally substituted, vinyl, alkynyl of 2 to 12 carbon atoms optionally substituted and halogen;
R is selected from alkyl of 1 to 12 carbon atoms optionally substituted, alkenyl of 2 to 12 carbon atoms optionally substituted, alkynyl of 2 to 12 carbon atoms optionally substituted, —CH 2 NR 1 R 2 , aryl of 6, 10 or 14 carbon atoms optionally substituted, aralkyl of 7 to 16 carbon atoms optionally substituted, aroyl of 7 to 13 carbon atoms optionally substituted, SR 3 , heteroaryl of 5 or 6 ring atoms optionally substituted, containing 1 to 4 heteroatoms which may be the same or different, independently selected from nitrogen, oxygen and sulfur, and heteroarylcarbonyl of 5 or 6 ring atoms optionally substituted containing 1 to 4 heteroatoms which may be the same or different, independently selected from nitrogen, oxygen and sulfur;
R 1 and R 2 are each independently H or alkyl of 1 to 12 carbon atoms or
R 1 and R 2 when optionally taken together with the nitrogen atom to which each is attached form a 3 to 7 membered saturated hydrocarbon ring;
R 3 is alkyl of 1 to 12 carbon atoms optionally substituted, —CH 2 -aryl optionally substituted, aralkyl of 7 to 16 carbon atoms optionally substituted, aroyl, —CH 2 (CO)OCH 2 aryl optionally substituted, —CH 2 -alkenyl of 2 to 12 carbon atoms optionally substituted, and —CH 2 -alkynyl of 2 to 12 carbon atoms optionally substituted; with the provisos that when X is NR 11 R 12 and R 11 is hydrogen, then R 12 is methyl, ethyl, n-propyl, n-butyl, 1-methylethyl, 1-methylpropyl, 2-methylpropyl or 1,1-dimethylethyl; and that when R 11 is methyl or ethyl then R 12 is methyl, ethyl, n-propyl, 1-methylethyl, n-propyl, 1-methylpropyl, or 2-methylpropyl; or a tautomer or pharmaceutically acceptable salts thereof.
DEFINITIONS
[0009] The term alkyl as a group or part of a group means a straight or branched alkyl moiety of 1 to 12 carbon atoms which can be optionally independently substituted with 1 to 3 substituents selected from the group halogen, amino, cyano, cycloalkyl of 3 to 6 carbon atoms, alkyl of 1 to 12 carbon atoms, aryl optionally substituted, phenyl, hydroxyl, alkoxy of 1 to 12 carbon atoms, NH-alkyl of 1 to 12 carbon atoms, N-cycloalkyl of 3 to 6 carbon atoms, NH-(alkyl of 1 to 12 carbon atoms)-aryl optionally substituted and heterocyclyl of 3 to 8 membered ring. In some embodiments of the invention alkyl is a moiety of 1 to 6 carbon atoms. In other embodiments of the invention alkyl is a moiety of 1 to 3 carbon atoms. In other embodiments alkyl is substituted by heterocyclyl of 4 to 7 ring members (e.g. pyrrolidinyl).
[0010] The term alkenyl means a straight or branched carbon chain of 2 to 12 carbon atoms having at least one site of unsaturation optionally independently substituted with 1 to 3 substituents selected from the group optionally substituted aryl, phenyl, heteroaryl, halogen, amino, cyano, alkyl of 1 to 12 carbon atoms, hydroxyl, and alkoxy of 1 to 12 carbon atoms.
[0011] The term vinyl means a moiety CH 2 ═CH—.
[0012] As used herein the term alkoxy as a group or part of a group refers to alkyl-O— wherein alkyl is hereinbefore defined.
[0013] As used herein the term aryl as a group or part of a group, e.g., aralkyl, aroyl, means an aromatic moiety having 6, 10 or 14 carbon atoms preferably 6 to 10 carbon atoms, which can be optionally substituted with 1 to 3 substituents independently selected from halogen, nitro, cyano, alkenyl, hydroxyl, alkyl, haloalkyl, alkoxy, benzyloxy, amino, alkylamino, dialkylamino, carboxyl, alkoxycarbonyl, methylenedioxy and phenyl. In particular, aryl is phenyl or naphthyl optionally substituted with 1 to 3 substituents. Substituted phenyl may optionally be the moiety
[0000]
[0014] The term aralkyl as used herein of 7 to 16 carbon atoms means an alkyl substituted with an aryl group in which the aryl and alkyl group are previously defined. Non-limiting exemplary aralkyl groups include benzyl and phenethyl and the like.
[0015] Phenyl as used herein refers to a 6-membered carbon aromatic ring.
[0016] As used herein the term alkynyl includes both straight chain and branched moieties containing 2 to 12 carbon atoms having at least one carbon to carbon triple bond optionally substituted with 1 to 3 substituents independently selected from the group halogen, amino, cyano, alkyl of 1 to 12 carbon atoms, hydroxyl, and alkoxy of 1 to 12 carbon atoms.
[0017] As used herein the term halogen or halo means F, Cl, Br or I.
[0018] As used herein the term cycloalkyl means a saturated monocyclic ring having from 3 to 6 carbon atoms. Exemplary cycloalkyl rings include but are not limited to cyclopropyl, cyclobutyl, cyclopentyl, and cyclohexyl. In an embodiment of the invention cycloalkyl is a moiety of 5 or 6 carbon atoms.
[0019] As used herein, R 1 and R 2 and R 11 and R 12 when optionally taken together with the nitrogen atom to which each is attached form a 3 to 7 membered saturated hydrocarbon ring, where a non-limiting example is pyrrolidinyl,
[0000]
[0020] The term aroyl means an aryl-C(O)— group in which the aryl group is as previously defined. Non-limiting examples include benzoyl and naphthoyl.
[0021] The term heteroaryl means an aromatic heterocyclic, monocyclic ring of 5 or 6 ring atoms containing 1 to 4 heteroatoms independently selected from O, N and S. Heteroaryl rings may optionally be substituted with 1 to 3 substitutents selected from the group halogen, cyano, nitro, hydroxy, amino, alkylamino, dialkylamino, alkoxy, aryloxy, —CH 2 OCOCH 3 and carboxy. Non-limiting heteroaryl moieties optionally substituted include: furanyl, thienyl, pyridyl, tetrazolyl, imidazo, thiazolyl and the like. Further included are benzofuranyl, benzothienyl and quinolinyl.
[0022] The term heteroarylcarbonyl means a heteroaryl-C(O)— group in which the heteroaryl group is as previously defined.
[0023] The term heterocyclyl as used herein represents a saturated 3 to 8 membered ring containing one to three heteroatoms selected from nitrogen, oxygen and sulfur. Representative examples are pyrrolidyl, piperidyl, piperazinyl, morpholinyl, thiomorpholinyl, aziridinyl, tetrahydrofuranyl and the like.
[0024] The term alkylheterocyclyl means an alkyl-heterocyclyl group in which the alkyl and heterocyclyl group are previously defined. Non-limiting exemplary alkylheterocyclyl groups include moieties of the formulae:
[0000]
[0025] Some of the compounds of formula (I) may also exist in their tautomeric forms. Such forms although not explicitly indicated in the above formula are intended to be included within the scope of the present invention. For instance, compounds of formula (I) which exist as tautomers are depicted below:
[0000]
[0026] One embodiment of this invention is where R of Formula (I) is selected from the group alkyl of 1 to 6 carbon atoms, alkenyl of 2 to 6 carbon atoms, and alkyl-(heterocyclyl) selected from moieties of the group
[0000]
[0027] Another embodiment of the invention is where R of Formula (I) is phenyl optionally substituted with 1 to 3 substituents. In a preferred embodiment R is selected from moieties of the group
[0000]
[0028] A further preferred embodiment of the invention is where R is heteroaryl. In a preferred embodiment R is selected from moieties of the group
[0000]
[0029] An additional embodiment of the invention is where R is alkyl of 1 to 6 carbon atoms optionally substituted, alkenyl of 2 to 6 carbon atoms optionally substituted,
[0000]
[0000] (cycloalkyl of 5 to 6 carbon atoms).
[0000]
[0000] (alkyl of 1 to 6 carbon atoms) and
[0000]
[0000] (alkyl of 1 to 6 carbon atoms)-aryl optionally substituted.
[0030] In a preferred embodiment R is selected from moieties of the group
[0000]
[0031] An additional embodiment of the invention is where R of Formula (I) is S-alkyl of 1 to 12 carbon atoms, S—CH 2 -aryl optionally substituted and S—CH 2 (CO)OCH 2 aryl optionally substituted. In a preferred embodiment R is selected from moieties of the group
[0000]
[0032] Preferred compounds of the invention include those selected from the group:
(6aR,7aS,8S,11aS)-5,8-bis(dimethylamino)-2-(2,2-diphenylvinyl)-9,11a,12-trihydroxy-11,13-dioxo-6,6a,7,7a,8,11,11a,13-octahydrotetraceno[2,1-d][1,3]oxazole-10-carboxamide, (7aS,8S,11aS)-8-(dimethylamino)-9,11a,13-trihydroxy-2-(2-methyl-1-propenyl)-11,12-dioxo-7,7a,8,11,11a, 12-hexahydronaphthaceno[2,1-d][1,3]oxazole-10-carboxamide, (6aR,7aS,8S,11aS)-2-tert-butyl-5,8-bis(dimethylamino)-9,11a,12-trihydroxy-11,13-dioxo-6,6a,7,7a,8,11,11a,13-octahydrotetraceno[2,1-d][1,3]oxazole-10-carboxamide, (6aR,7aS,8S,11aS)-5,8-bis(dimethylamino)-2-[(E)-2-(2-furyl)ethenyl]-9,11a,12-trihydroxy-11,13-dioxo-6,6a,7,7a,8,11,11a,13-octahydrotetraceno[2,1-d][1,3]oxazole-10-carboxamide, (6aR,7aS,8S.11aS)-5,8-bis(dimethylamino)-9,11a,12-trihydroxy-11,13-dioxo-2-[(E)-2-phenylethenyl]-6,6a,7,7a,8,11,11a,13-octahydrotetraceno[2,1-d][1,3]oxazole-10-carboxamide, (6aR,7aS,8S,11aS)-5,8-bis(dimethylamino)-9,11a,12-trihydroxy-2-[(E)-2-(4-methoxyphenyl)ethenyl]-11,13-dioxo-6,6a,7,7a,8,11,11a,13-octahydrotetraceno[2,1-d][1,3]oxazole-10-carboxamide, (6aR,7aS,8S,1aS)-5,8-bis(dimethylamino)-9,11a,12-trihydroxy-2-[(E)-2-(3-methoxyphenyl)ethenyl]-11,13-dioxo-6,6a,7,7a,8,11,11a,13-octahydrotetraceno[2,1-d][1,3]oxazole-10-carboxamide, (6aR,7aS,8S,11aS)-5,8-bis(dimethylamino)-9,11a,12-trihydroxy-2-[(E)-2-(2-methoxyphenyl)ethenyl]-11,13-dioxo-6,6a,7,7a,8,11,11a,13-octahydrotetraceno[2,1-d][1,3]oxazole-10-carboxamide, (6aR,7aS,8S,11aS)-5,8-bis(dimethylamino)-2-[(E)-2-(4-fluorophenyl)ethenyl]-9,11a,12-trihydroxy-11,13-dioxo-6,6a,7,7a,8,11,11a,13-octahydrotetraceno[2,1-d][1,3]oxazole-10-carboxamide, (6aR,7aS,8S,11aS)-5,8-bis(dimethylamino)-2-[(E)-2-(2-fluorophenyl)ethenyl]-9,11a,12-trihydroxy-11,13-dioxo-6,6a,7,7a,8,11,11a,13-octahydrotetraceno[2,1-d][1,3]oxazole-10-carboxamide, (6aR,7aS,8S,11aS)-2-(chloromethyl)-5,8-bis(dimethylamino)-9,11a,12-trihydroxy-11,13-dioxo-6,6a,7,7a,8,11,11a,13-octahydrotetraceno[2,1-d][1,3]oxazole-10-carboxamide, (6aR,7aS,8S,11aS)-5,8-bis(dimethylamino)-2-[(dimethylamino)methyl]-9,11a,12-trihydroxy-11,13-dioxo-6,6a,7,7a,8,11,11a,13-octahydrotetraceno[2,1-d][1,3]oxazole-10-carboxamide, (6aR,7aS,8S,11aS)-5,8-bis(dimethylamino)-9,11a,12-trihydroxy-11,13-dioxo-2-(pyrrolidin-1-ylmethyl)-6,6a,7,7a,8,11,11a,13-octahydrotetraceno[2,1-d][1,3]oxazole-10-carboxamide, (6aR,7aS,8S,11aS)-5,8-bis(dimethylamino)-9,11a,12-trihydroxy-11,13-dioxo-2-[(propylamino)methyl]-6,6a,7,7a,8,11,11a,13-octahydrotetraceno[2,1-d][1,3]oxazole-10-carboxamide, (6aR,7aS,8S,11aS)-2-[(butylamino)methyl]-5,8-bis(dimethylamino)-9,11a,12-trihydroxy-11,13-dioxo-6,6a,7,7a,8,11,11a,13-octahydrotetraceno[2,1-d][1,3]oxazole-10-carboxamide, (6aR,7aS,8S,11aS)-5,8-bis(dimethylamino)-9,11a,12-trihydroxy-11,13-dioxo-2-[(propylamino)methyl]-6,6a,7,7a,8,11,11a,13-octahydrotetraceno[2,1-d][1,3]oxazole-10-carboxamide and (6aR,7aS,8S,11aS)-2-[(tert-butylamino)methyl]-5,8-bis(dimethylamino)-9,11a,12-trihydroxy-11,13-dioxo-6,6a,7,7a,8,11,11a,13-octahydrotetraceno[2,1-d][1,3]oxazole-10-carboxamide.
[0050] Preferred compounds of the invention include those selected from the group:
(7aS,8S,11aS)-8-(dimethylamino)-2-[4-(dimethylamino)phenyl]-9,11a,13-trihydroxy-11,12-dioxo-7,7a,8,11,11a,12-hexahydronaphthaceno[2,1-d][1,3]oxazole-10-carboxamide, (6aR,7aS,8S,11aS)-2-tert-butyl-5,8-bis(dimethylamino)-9,11a,12-trihydroxy-11,13-dioxo-6,6a,7,7a,8,11,11a,13-octahydrotetraceno[2,1-d][1,3]oxazole-10-carboxamide, (6aR,7aS,8S,11aS)-5,8-bis(dimethylamino)-9,11a,12-trihydroxy-2-(4-methylphenyl)-11,13-dioxo-6,6a,7,7a,8,11,11a,13-octahydrotetraceno[2,1-d][1,3]oxazole-10-carboxamide, (7aS,8S,11aS)-5,8-bis(dimethylamino)-2-(3-fluorophenyl)-9,11a,13-trihydroxy-11,12-dioxo-7,7a,8,11,11a, 12-hexahydrotetraceno[2,1-d][1,3]oxazole-10-carboxamide, (6aR,7aS,8S,11aS)-2-(4-cyanophenyl)-5,8-bis(dimethylamino)-9,11a,12-trihydroxy-11,13-dioxo-6,6a,7,7a,8,11,11a,13-octahydrotetraceno[2,1-d][1,3]oxazole-10-carboxamide, (6aR,7aS,8S,11aS)-5,8-bis(dimethylamino)-2-[4-(dimethylamino)phenyl]-9,11a,12-trihydroxy-11,13-dioxo-6,6a,7,7a,8,11,11a,13-octahydrotetraceno[2,1-d][1,3]oxazole-10-carboxamide, (6aR,7aS,8S,11aS)-2-(5-tert-butyl-2-hydroxyphenyl)-5,8-bis(dimethylamino)-9,11a,12-trihydroxy-11,13-dioxo-6,6a,7,7a,8,11,11a,13-octahydrotetraceno[2,1-d][1,3]oxazole-10-carboxamide, (6aR,7aS,8S,11aS)-2-[4-(benzyloxy)phenyl]-5,8-bis(dimethylamino)-9,11a,12-trihydroxy-11,13-dioxo-6,6a,7,7a,8,11,11a,13-octahydrotetraceno[2,1-d][1,3]oxazole-10-carboxamide, (6aR,7aS,8S,11aS)-2-(2,4-dihydroxyphenyl)-5,8-bis(dimethylamino)-9,11a,12-trihydroxy-11,13-dioxo-6,6a,7,7a,8,11,11a,13-octahydrotetraceno[2,1-d][1,3]oxazole-10-carboxamide, (6aR,7aS,8S,11aS)-5,8-bis(dimethylamino)-2-(3-fluoro-4-methoxyphenyl)-9,11a,12-trihydroxy-11,13-dioxo-6,6a,7,7a,8,11,11a,13-octahydrotetraceno[2,1-d][1,3]oxazole-10-carboxamide, (6aR,7aS,8S,11aS)-2-(1,3-benzodioxol-5-yl)-5,8-bis(dimethylamino)-9,11a,12-trihydroxy-11,13-dioxo-6,6a,7,7a,8,11,11a,13-octahydrotetraceno[2,1-d][1,3]oxazole-10-carboxamide, (6aR,7aS,8S,11aS)-5,8-bis(dimethylamino)-9,11a,12-trihydroxy-11,13-dioxo-2-(2,4,6-trimethoxyphenyl)-6,6a,7,7a,8,11,11a,13-octahydrotetraceno[2,1-d][1,3]oxazole-10-carboxamide, (6aR,7aS,8S,11aS)-5,8-bis(dimethylamino)-9,11a,12-trihydroxy-11,13-dioxo-2-(2,4,5-triethoxyphenyl)-6,6a,7,7a,8,11,11a,13-octahydrotetraceno[2,1-d][1,3]oxazole-10-carboxamide, (6aR,7aS,8S,11aS)-5,8-bis(dimethylamino)-9,11a,12-trihydroxy-2-(1-methyl-1H-indol-2-yl)-11,13-dioxo-6,6a,7,7a,8,11,11a,13-octahydrotetraceno[2,1-d][1,3]oxazole-10-carboxamide, (6aR,7aS,8S,11aS)-2-(4-tert-butylphenyl)-5,8-bis(dimethylamino)-9,11a,12-trihydroxy-11,13-dioxo-6,6a,7,7a,8,11,11a,13-octahydrotetraceno[2,1-d][1,3]oxazole-10-carboxamide and (6aR,7aS,8S,11aS)-5,8-bis(dimethylamino)-2-[4-(hexyloxy)phenyl]-9,11a,12-trihydroxy-11,13-dioxo-6,6a,7,7a,8,11,11a,13-octahydrotetraceno[2,1-d][1,3]oxazole-10-carboxamide.
[0066] Preferred compounds include those selected from the group:
(6aR,7aS,8S,11aS)-5,8-bis(dimethylamino)-9,11a,12-trihydroxy-11,13-dioxo-2-thien-3-yl-6,6a,7,7a,8,11,11a,13-octahydrotetraceno[2,1-d][1,3]oxazole-10-carboxamide, (6aR,7aS,8S,11aS)-2-(1-benzofuran-2-yl)-5,8-bis(dimethylamino)-9,11a,12-trihydroxy-11,13-dioxo-6,6a,7,7a,8,11,11a,13-octahydrotetraceno[2,1-d][1,3]oxazole-10-carboxamide, (6aR,7aS,8S,11aS)-5,8-bis(dimethylamino)-2-(2-furyl)-9,11a,12-trihydroxy-11,13-dioxo-6,6a,7,7a,8,11,11a,13-octahydrotetraceno[2,1-d][1,3]oxazole-10-carboxamide, {5-[(6aR,7aS,8S,11aS)-10-(aminocarbonyl)-5,8-bis(dimethylamino)-9,11a,12-trihydroxy-111,13-dioxo-6,6a,7,7a,8,11,11a,13-octahydrotetraceno[2,1-d][1,3]oxazol-2-yl]-2-furyl}methyl acetate, (6aR,7aS,8S,11aS)-2-(1-benzothien-3-yl)-5,8-bis(dimethylamino)-9,11a,12-trihydroxy-11,13-dioxo-6,6a,7,7a,8,11,11a,13-octahydrotetraceno[2,1-d][1,3]oxazole-10-carboxamide, (6aR,7aS,8S,11aS)-5,8-bis(dimethylamino)-9,11a,12-trihydroxy-11,13-dioxo-2-(1,3-thiazol-2-yl)-6,6a,7,7a,8,11,11a,13-octahydrotetraceno[2,1-d][1,3]oxazole-10-carboxamide, (6aR,7aS,8S,11aS)-5,8-bis(dimethylamino)-9,11a,12-trihydroxy-11,13-dioxo-2-pyridin-4-yl-6,6a,7,7a,8,11,11a,13-octahydrotetraceno[2,1-d][1,3]oxazole-10-carboxamide and (6aR,7aS,8S,11aS)-5,8-bis(dimethylamino)-9,11a,12-trihydroxy-11,13-dioxo-2-pyridin-3-yl-6,6a,7,7a,8,11,11a,13-octahydrotetraceno[2,1-d][1,3]oxazole-10-carboxamide.
[0075] An additional embodiment of the invention is a process for the preparation of a compound of the formula
[0000]
[0000] or a pharmaceutically acceptable salt thereof
wherein:
X is selected from hydrogen, amino, NR 11 R 12 , alkyl of 1 to 12 carbon atoms optionally substituted, aryl of 6, 10 or 14 carbon atoms optionally substituted, vinyl optionally substituted, alkynyl of 2 to 12 carbon atoms optionally substituted and halogen;
R 1 and R 2 are each independently H or alkyl of 1 to 12 carbon atoms or
R 1 and R 2 when optionally taken together with the nitrogen atom to which each is attached form a 3 to 7 membered saturated hydrocarbon ring;
R 11 and R 12 are each independently H or alkyl of 1 to 12 carbon atoms or
R 11 and R 12 when optionally taken together with the nitrogen atom to which each is attached form a 3 to 7 membered saturated hydrocarbon ring;
Y is selected from hydrogen, alkyl of 1 to 12 carbon atoms optionally substituted, aryl of 6, 10 or 14 carbon atoms optionally substituted, alkenyl of 2 to 12 carbon atoms optionally substituted, vinyl, alkynyl of 2 to 12 carbon atoms optionally substituted and halogen;
comprising the steps:
a. reacting 7-(substituted)-8-(substituted)-9-amino-6-demethyl-6-deoxytetracycline of the formula
[0000]
[0000] or a pharmaceutically acceptable salt thereof
with 2-chlorotrimethoxyethane in an aprotic solvent to afford a chloro compound of the formula
[0000]
[0000] b. reacting the chloro compound with an amine R 1 R 2 NH to form a substituted amine of the formula
[0000]
[0000] c. hydrolyzing the substituted amine with acid to give a compound of the formula
[0000]
[0000] d. isolating the compound or a pharmaceutically acceptable salt thereof.
[0076] In a preferred embodiment of the process X is N(CH 3 ) 2 and the amine R 1 R 2 NH is t-butyl amine.
[0077] In a preferred embodiment of the process the compound [4S-(4α,4aα,5aα,12aα)]-4,7-Bis(dimethylamino)-9-[2-(1,1-dimethylethylamino)acetylamino]-1,4,4a,5,5a,6,11,12a-octahydro-3,10,12,12a-tetrahydroxy-1,11-dioxo-2-naphthacenecarboxamide or a pharmaceutically acceptable salt thereof is prepared.
[0078] A further embodiment of the invention is a process for the preparation of a compound of the formula
[0000]
[0000] wherein:
X is selected from hydrogen, amino, NR 11 R 12 , alkyl of 1 to 12 carbon atoms optionally substituted, aryl of 6, 10 or 14 carbon atoms optionally substituted, vinyl, optionally substituted, alkynyl of 2 to 12 carbon atoms optionally substituted and halogen;
R 1 and R 2 are each independently H or alkyl of 1 to 12 carbon atoms or
R 1 and R 2 when optionally taken together with the nitrogen atom to which each is attached form a 3 to 7 membered saturated hydrocarbon ring;
R 11 and R 12 are each independently H or alkyl of 1 to 12 carbon atoms or
R 11 and R 12 when optionally taken together with the nitrogen atom to which each is attached form a 3 to 7 membered saturated hydrocarbon ring;
Y is selected from hydrogen, alkyl of 1 to 12 carbon atoms optionally substituted, aryl of 6, 10 or 14 carbon atoms optionally substituted, alkenyl of 2 to 12 carbon atoms optionally substituted, vinyl, alkynyl of 2 to 12 carbon atoms optionally substituted and halogen;
or a pharmaceutically acceptable salt thereof
comprising the steps:
a. reacting 7-(substituted)-8-(substituted)-9-amino-6-demethyl-6-deoxytetracycline of the formula
[0000]
[0000] or a pharmaceutically acceptable salt thereof
with 2-chlorotrimethoxyethane in an aprotic solvent to afford a chloro compound of the formula
[0000]
[0000] b. reacting the chloro compound with acid to give 9-(2-chloromethylcarbonylamino)substituted-6-demethyl-6-deoxytetracycline of the formula
[0000]
[0000] c. reacting the 9-(2-chloromethylcarbonylamino)substituted-6-demethyl-6-deoxytetracycline with amine R 1 R 2 NH to give a compound of the formula
[0000]
[0000] d. isolating the compound or a pharmaceutically acceptable salt thereof.
[0079] In a preferred embodiment of the process X is N(CH 3 ) 2 and the amine R 1 R 2 NH is t-butyl amine.
[0080] In a preferred embodiment of the process the compound [4S-(4α,4aα,5aα,12aα)]-4,7-Bis(dimethylamino)-9-[2-(1,1-dimethylethylamino)acetylamino]-1,4,4a,5,5a,6,11,12a-octahydro-3,10,12,12a-tetrahydroxy-1,11-dioxo-2-naphthacenecarboxamide or a pharmaceutically acceptable salt thereof is prepared.
[0081] An additional embodiment of the invention is a compound of the formula
[0000]
[0000] or a pharmaceutically acceptable salt thereof
wherein:
X is selected from hydrogen, amino, NR 11 R 12 , alkyl of 1 to 12 carbon atoms optionally substituted, aryl of 6, 10 or 14 carbon atoms optionally substituted, vinyl optionally substituted, alkynyl of 2 to 12 carbon atoms optionally substituted and halogen;
R 1 and R 2 are each independently H or alkyl of 1 to 12 carbon atoms or
R 1 and R 2 when optionally taken together with the nitrogen atom to which each is attached form a 3 to 7 membered saturated hydrocarbon ring;
R 11 and R 12 are each independently H or alkyl of 1 to 12 carbon atoms or
R 11 and R 12 when optionally taken together with the nitrogen atom to which each is attached form a 3 to 7 membered saturated hydrocarbon ring;
Y is selected from hydrogen, alkyl of 1 to 12 carbon atoms optionally substituted, aryl of 6, 10 or 14 carbon atoms optionally substituted, alkenyl of 2 to 12 carbon atoms optionally substituted, vinyl, alkynyl of 2 to 12 carbon atoms optionally substituted and halogen;
produced by the process comprising the steps:
a. reacting 7-(substituted)-8-(substituted)-9-amino-6-demethyl-6-deoxytetracycline of the formula
[0000]
[0000] or a pharmaceutically acceptable salt thereof
with 2-chlorotrimethoxyethane in an aprotic solvent to afford a chloro compound of the formula
[0000]
[0000] b. reacting the chloro compound with an amine R 1 R 2 NH to form a substituted amine of the formula
[0000]
[0000] c. hydrolyzing the substituted amine with acid to give a compound of the formula
[0000]
[0000] d. isolating the compound or a pharmaceutically acceptable salt thereof.
[0082] In a preferred embodiment of the process X is N(CH 3 ) 2 and the amine R 1 R 2 NH is t-butyl amine.
[0083] In a preferred embodiment of the process the compound [4S-(4α,4aα,5aα,12aα)]-4,7-Bis(dimethylamino)-9-[2-(1,1-dimethylethylamino)acetylamino]-1,4,4a,5,5a,6,11,12a-octahydro-3,10,12,12a-tetrahydroxy-1,1′-dioxo-2-naphthacenecarboxamide or a pharmaceutically acceptable salt thereof is prepared.
[0084] In an additional embodiment of the invention a compound of the formula
[0000]
[0000] wherein:
X is selected from hydrogen, amino, NR 11 R 12 , alkyl of 1 to 12 carbon atoms optionally substituted, aryl of 6, 10 or 14 carbon atoms optionally substituted, vinyl optionally substituted, alkynyl of 2 to 12 carbon atoms optionally substituted and halogen;
R 1 and R 2 are each independently H or alkyl of 1 to 12 carbon atoms or when optionally taken together with the nitrogen atom to which each is attached form a 3 to 7 membered saturated hydrocarbon ring;
R 11 and R 12 are each independently H or alkyl of 1 to 12 carbon atoms or
R 11 and R 12 when optionally taken together with the nitrogen atom to which each is attached form a 3 to 7 membered saturated hydrocarbon ring;
Y is selected from hydrogen, alkyl of 1 to 12 carbon atoms optionally substituted, aryl of 6, 10 or 14 carbon atoms optionally substituted, alkenyl of 2 to 12 carbon atoms optionally substituted, vinyl, alkynyl of 2 to 12 carbon atoms optionally substituted and halogen;
or a pharmaceutically acceptable salt thereof
produced by the process comprising the steps:
a. reacting 7-(substituted)-8-(substituted)-9-amino-6-demethyl-6-deoxytetracycline of the formula
[0000]
[0000] or a pharmaceutically acceptable salt thereof
with 2-chlorotrimethoxyethane in an aprotic solvent to afford a chloro compound of the formula
[0000]
[0000] b. reacting the chloro compound with acid to give 9-(2-chloromethylcarbonylamino)substituted-6-demethyl-6-deoxytetracycline of the formula
[0000]
[0000] c. reacting the 9-(2-chloromethylcarbonylamino)substituted-6-demethyl-6-deoxytetracycline with amine R 1 R 2 NH to give a compound of the formula
[0000]
[0000] d. isolating the compound or a pharmaceutically acceptable salt thereof.
[0085] In a preferred embodiment of the process X is N(CH 3 ) 2 and the amine R 1 R 2 NH is t-butyl amine.
[0086] In a preferred embodiment the compound [4S-(4α,4aα,5aα,12aα)]-4,7-Bis(dimethylamino)-9-[2-(1,1-dimethylethylamino)acetylamino]-1,4,4a,5,5a,6,11,12a-octahydro-3,10,12,12a-tetrahydroxy-1,11-dioxo-2-naphthacenecarboxamide or a pharmaceutically acceptable salt thereof is prepared by the process.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0087] The novel compounds of the present invention may be readily prepared in accordance with the following Scheme I.
[0088] The starting 7-(substituted)-8-(substituted)-9-amino-6-demethyl-6-deoxytetracyclines 1 or pharmaceutically acceptable salts thereof where X and Y are hereinbefore defined are reacted with aldehyde RCHO in the presence of 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ) to afford benzoxazole 2 and 3 (Procedure A). As further described, reaction of 7-(substituted)-8-(substituted)-9-amino-6-demethyl-6-deoxytetracyclines 1 or pharmaceutically acceptable salts thereof where X and Y are hereinbefore defined are reacted with 2-chloro-1,1,1-trimethoxy-ethane in an aprotic solvent such as N,N-dimethylformamide (DMF) to give chloromethyl-benzoxazole 4, optionally isolated, then converted to substituted amine 5 by further reaction with an amine 9 (Procedure B). Hydrolysis of amine 5 affords 9-(2-substituted aminomethyl carbonylamino)substituted-6-dimethyl-6-deoxytetracycline 6 (Procedure D). Hydrolysis of chloromethylbenzoxazole 4 gives 9-(2-chloromethylcarbonyl-amino)substituted-6-demethyl-6-deoxytetracycline 7 which may be further reacted with amine 9 to give 9-(2-substituted aminomethyl carbonylamino)substituted-6-dimethyl-6-deoxytetracycline 6.
[0089] Additionally, reaction of 7-(substituted)-8-(substituted)-9-amino-6-demethyl-6-deoxytetracyclines 1 or pharmaceutically acceptable salts thereof with thiocarbonyldiimidazole provides thio 8 followed by alkylation with RCH 2 Br in the presence of an amine which includes N,N-diisopropylethylamine affords oxazole 10 (Procedure C).
[0090] Preferably, amine 9 in the preparation of 9-(2-substituted aminomethyl carbonylamino)substituted-6-dimethyl-6-deoxytetracycline 6, in Scheme I is t-butylamine.
[0000]
[0091] As shown in Scheme II, the starting 7-(substituted)-8-(substituted)-9-amino-6-demethyl-6-deoxytetracyclines 1 or pharmaceutically acceptable salts thereof where X and Y are hereinbefore defined are reacted with a methyl orthoester to afford methyl benzoxazole derivative 11. Acid hydrolysis of methyl benzoxazole derivative 11 affords N-acetyl derivative 12.
[0000]
[0092] Reactions are performed in a solvent appropriate to the reagents and materials employed and suitable for the transformation being effected. It is understood by those skilled in the art of organic synthesis that the various functionalities present on the molecule must be consistent with the chemical transformations proposed. This may necessitate judgement as to the order of synthetic steps, protecting groups, if required, and deprotection conditions. Substituents on the starting materials may be incompatible with some of the reaction conditions. Such restrictions to the substituents which are compatible with the reaction conditions will be apparent to one skilled in the art.
[0093] Some of the compounds of the hereinbefore described schemes have center of asymmetry. The compounds may, therefore, exist in at least two and often more stereoisomeric forms. The present invention encompasses all stereoisomers of the compounds whether free from other stereoisomers or admixed with other stereoisomers in any proportion and thus includes, for instance, racemic mixture of enantiomers as well as the diastereomeric mixture of isomers. The absolute configuration of any compound may be determined by conventional X-ray crystallography.
[0094] Pharmaceutically acceptable salts of the compounds of the invention may be obtained as metal complexes such as aluminum, calcium, iron, magnesium, manganese and complex salts; inorganic and organic salts and corresponding Mannich base adducts using methods known to those skilled in the art (Richard C. Larock, Comprehensive Organic Transformations, VCH Publishers, 411-415, 1989). Preferably, the compounds of the invention are obtained as inorganic salts such as hydrochloric, hydrobromic, hydroiodic, phosphoric, nitric or sulfate; or organic salts such as acetate, benzoate, citrate, cysteine or other amino acids, fumarate, glycolate, maleate, succinate, tartrate alkylsulfonate or arylsulfonate. The salt formation preferentially occurs with the C(4)-dimethylamino group when forming inorganic salts. The salts are preferred for oral and parenteral administration.
Standard Pharmacological Test Procedures
Methods for In Vitro Antibacterial Evaluation
The Minimum Inhibitory Concentration (MIC)
[0095] Antimicrobial susceptibility testing. The in vitro activities of the antibiotics are determined by the broth microdilution method as recommended by the National Committee for Clinical Laboratory Standards (NCCLS) (1). Mueller-Hinton II broth (MHBII)(BBL Cockeysville, Md.) is the medium employed in the testing procedures. Microtiter plates containing serial dilutions of each antimicrobial agent are inoculated with each organism to yield the appropriate density (10 5 CFU/ml) in a 100 μl final volume. The plates are incubated for 18-22 hours at 35° C. in ambient air. The minimal inhibitory concentration for all isolates is defined as the lowest concentration of antimicrobial agent that completely inhibits the growth of the organism as detected by the unaided eye.
1. NCCLS. 2000. Methods for Dilution Antimicrobial Susceptibility Tests for Bacteria That Grow Aerobically; Approved Standards: M7-A5, vol. 20. National Committee for Clinical Laboratory Standards, Wayne, Pa.
[0000]
TABLE I
ANTIBACTERIAL ACTIVITY OF (7-SUBSTITUTED)-8-(SUBSTITUTED)-9-(SUBSTITUTED)-TETRACYCLINES
MIC (μg/ml) COMPOUND
Example 1
Example 2
Example 3
Example 4
Example 5
Example 6
1
E. coli GC2270 (tet(M))
>64
>64
>64
>64
>64
>64
2
E. coli GC4559 (parent GC4560)
>64
>64
>64
>64
>64
>64
3
E. coli GC4560 (IMP mutant)
32
8
16
16
4
8
4
E. coli GC2203 (ATCC Control)
>64
>64
>64
>64
>64
>64
5
E. coli GC1073 (tet(B))
>64
>64
>64
>64
>64
>64
6
S. aureus GC1131 (Clinical)
16
8
2
16
4
4
7
S. aureus GC6466 (tet(M))
32
8
2
32
4
4
8
S. aureus GC6467 (tet(M) + (K))
32
8
2
32
4
4
9
S. aureus GC1079 (tet(K))
16
8
1
16
4
4
10
S. aureus GC4536 (Smith MP -In Vivo)
16
8
2
32
4
4
11
S. aureus GC2216 (ATCC Control)
16
8
2
32
4
4
12
E. faecalis GC4555 (ATCC Control)
32
8
2
32
4
8
13
E. faecalis GC2267 (tet(L) + (M) + (S))
32
8
2
32
4
4
14
E. faecalis GC2242 (Van-resistant)
16
8
2
32
4
4
15
S. pneumoniae * GC4465 (Clinical)
16
8
2
16
16
16
16
S. pneumoniae * GC1894 (Clinical)
8
32
8
16
17
S. pyogenes * GC4563 (Clinical)
8
8
8
16
16
16
18
M. catarrhalis * GC6907 (Clinical)
>64
16
16
32
19
H. influenzae <> GC6896 (ATCC Control)
>64
>64
>64
>64
20
C. albicans GC3066 ATCC (Control)
>64
>64
>64
>64
>64
>64
[0000]
TABLE II
ANTIBACTERIAL ACTIVITY OF (7-SUBSTITUTED)-8-
(SUBSTITUTED)-9-SUBSTITUTED)-TETRACYCLINES
MIC (μg/ml) COMPOUND
Example 7
Example 8
Example 10
Example 11
1
E. coli GC2270 (tet(M))
>64
>64
>64
>64
2
E. coli GC4559 (parent GC4560)
>64
>64
>64
>64
3
E. coli GC4560 (IMP mutant)
8
16
32
>64
4
E. coli GC2203 (ATCC Control)
>64
>64
>64
>64
5
E. coli GC1073 (tet(B))
>64
>64
>64
>64
6
S. aureus GC1131 (Clinical)
8
8
8
32
7
S. aureus GC6466 (tet(M))
8
16
16
64
8
S. aureus GC6467 (tet(M) + (K))
8
8
16
32
9
S. aureus GC1079 (tet(K))
8
16
16
64
10
S. aureus GC4536 (Smith MP -In Vivo)
8
16
16
64
11
S. aureus GC2216 (ATCC Control)
8
8
16
64
12
E. faecalis GC4555 (ATCC Control)
8
32
16
64
13
E. faecalis GC2267 (tet(L) + (M) + (S))
8
16
16
>64
14
E. faecalis GC2242 (Van-resistant)
8
8
8
64
15
S. pneumoniae * GC4465 (Clinical)
8
32
16
32
16
S. pneumoniae * GC1894 (Clinical)
16
16
8
32
17
S. pyogenes * GC4563 (Clinical)
8
16
16
32
18
M. catarrhalis * GC6907 (Clinical)
4
64
>64
32
19
H. influenzae <> GC6896 (ATCC Control)
64
>64
>64
>64
20
C. albicans GC3066 ATCC (Control)
>64
>64
>64
>64
[0000]
TABLE III
ANTIBACTERIAL ACTIVITY OF (7-SUBSTITUTED)-8-(SUBSTITUTED)-9-(SUBSTITUTED)-TETRACYCLINES
MIC (μg/ml) COMPOUND
Example 12
Example 13
Example 14
Example 15
Example 16
1
E. coli GC2270 (tet(M))
>64
>64
>64
>64
>64
2
E. coli GC4559 (parent GC4560)
>64
>64
>64
>64
>64
3
E. coli GC4560 (IMP mutant)
4
4
16
32
16
4
E. coli GC2203 (ATCC Control)
32
>64
>64
>64
>64
5
E. coli GC1073 (tet(B))
>64
>64
>64
>64
>64
6
S. aureus GC1131 (Clinical)
4
4
4
64
16
7
S. aureus GC6466 (tet(M))
8
4
4
64
16
8
S. aureus GC6467 (tet(M) + (K))
8
8
8
64
16
9
S. aureus GC1079 (tet(K))
8
4
4
64
16
10
S. aureus GC4536 (Smith MP -In Vivo)
8
8
4
64
16
11
S. aureus GC2216 (ATCC Control)
4
4
4
64
16
12
E. faecalis GC4555 (ATCC Control)
8
8
8
64
16
13
E. faecalis GC2267 (tet(L) + (M) + (S))
8
8
8
64
16
14
E. faecalis GC2242 (Van-resistant)
8
8
4
64
16
15
S. pneumoniae * GC4465 (Clinical)
8
32
16
>64
>64
16
S. pneumoniae * GC1894 (Clinical)
8
16
16
>64
>64
17
S. pyogenes * GC4563 (Clinical)
4
16
16
>64
64
18
M. catarrhalis * GC6907 (Clinical)
4
16
4
64
>64
19
H. influenzae <> GC6896 (ATCC Control)
16
>64
>64
>64
>64
20
C. albicans GC3066 ATCC (Control)
>64
>64
>64
>64
>64
[0000]
TABLE IV
ANTIBACTERIAL ACTIVITY OF (7-SUBSTITUTED)-8-(SUBSTITUTED)-9-(SUBSTITUTED)-TETRACYCLINES
MIC (μg/ml) COMPOUND
Example 17
Example 18
Example 19
Example 20
Example 21
1
E. coli GC2270 (tet(M))
>64
>64
>64
>64
>64
2
E. coli GC4559 (parent GC4560)
>64
>64
>64
>64
>64
3
E. coli GC4560 (IMP mutant)
4
4
4
32
>64
4
E. coli GC2203 (ATCC Control)
>64
>64
>64
>64
>64
5
E. coli GC1073 (tet(B))
>64
>64
>64
>64
>64
6
S. aureus GC1131 (Clinical)
8
4
4
32
64
7
S. aureus GC6466 (tet(M))
8
4
4
32
32
8
S. aureus GC6467 (tet(M) + (K))
8
4
4
32
32
9
S. aureus GC1079 (tet(K))
8
4
4
32
32
10
S. aureus GC4536 (Smith MP -In Vivo)
8
4
8
64
64
11
S. aureus GC2216 (ATCC Control)
8
4
4
32
32
12
E. faecalis GC4555 (ATCC Control)
8
4
8
64
>64
13
E. faecalis GC2267 (tet(L) + (M) + (S))
16
4
8
64
64
14
E. faecalis GC2242 (Van-resistant)
8
4
4
32
32
15
S. pneumoniae * GC4465 (Clinical)
32
16
4
>64
>64
16
S. pneumoniae * GC1894 (Clinical)
32
16
4
64
>64
17
S. pyogenes * GC4563 (Clinical)
16
16
8
32
>64
18
M. catarrhalis * GC6907 (Clinical)
16
8
16
32
>64
19
H. influenzae <> GC6896 (ATCC Control)
>64
>64
>64
>64
>64
20
C. albicans GC3066 ATCC (Control)
>64
>64
>64
>64
>64
[0000]
TABLE V
ANTIBACTERIAL ACTIVITY OF (7-SUBSTITUTED)-8-
(SUBSTITUTED)-9-SUBSTITUTED)-TETRACYCLINES
MIC (μg/ml) COMPOUND
Example 22
Example 24
Example 25
Example 26
1
E. coli GC2270 (tet(M))
>64
>64
>64
>64
2
E. coli GC4559 (parent GC4560)
>64
>64
>64
>64
3
E. coli GC4560 (IMP mutant)
8
32
8
32
4
E. coli GC2203 (ATCC Control)
>64
>64
>64
>64
5
E. coli GC1073 (tet(B))
>64
>64
>64
>64
6
S. aureus GCH31 (Clinical)
8
32
8
16
7
S. aureus GC6466 (tet(M))
8
32
4
16
8
S. aureus GC6467 (tet(M) + (K))
8
32
8
16
9
S. aureus GC1079 (tet(K))
8
32
4
32
10
S. aureus GC4536 (Smith MP -In Vivo)
8
32
8
32
11
S. aureus GC2216 (ATCC Control)
8
64
4
16
12
E. faecalis GC4555 (ATCC Control)
8
32
8
32
13
E. faecalis GC2267 (tet(L) + (M) + (S))
8
32
4
16
14
E. faecalis GC2242 (Van-resistant)
8
32
4
16
15
S. pneumoniae * GC4465 (Clinical)
32
64
32
>64
16
S. pneumoniae * GC1894 (Clinical)
32
64
32
>64
17
S. pyogenes * GC4563 (Clinical)
16
32
16
64
18
M. catarrhalis * GC6907 (Clinical)
16
>64
16
>64
19
H. influenzae <> GC6896 (ATCC Control)
>64
>64
>64
>64
20
C. albicans GC3066 ATCC (Control)
>64
>64
>64
>64
[0000]
TABLE VI
ANTIBACTERIAL ACTIVITY OF (7-SUBSTITUTED)-8-(SUBSTITUTED)-9-(SUBSTITUTED)-TETRACYCLINES
MIC (μg/ml) COMPOUND
Example 27
Example 28
Example 29
Example 30
Example 31
1
E. coli GC2270 (tet(M))
>64
>64
>64
>64
>64
2
E. coli GC4559 (parent GC4560)
>64
>64
>64
>64
>64
3
E. coli GC4560 (IMP mutant)
32
16
8
8
4
4
E. coli GC2203 (ATCC Control)
>64
>64
>64
>64
>64
5
E. coli GC1073 (tet(B))
>64
>64
>64
>64
>64
6
S. aureus GC1131 (Clinical)
8
8
8
4
8
7
S. aureus GC6466 (tet(M))
16
8
8
8
4
8
S. aureus GC6467 (tet(M) + (K))
8
8
8
8
8
9
S. aureus GC1079 (tet(K))
8
16
8
8
8
10
S. aureus GC4536 (Smith MP -In Vivo)
16
16
8
8
8
11
S. aureus GC2216 (ATCC Control)
8
8
8
4
8
12
E. faecalis GC4555 (ATCC Control)
16
16
8
8
8
13
E. faecalis GC2267 (tet(L) + (M) + (S))
8
8
8
4
8
14
E. faecalis GC2242 (Van-resistant)
8
8
8
4
8
15
S. pneumoniae * GC4465 (Clinical)
64
32
32
16
8
16
S. pneumoniae * GC1894 (Clinical)
64
64
32
16
8
17
S. pyogenes * GC4563 (Clinical)
64
16
16
16
8
18
M. catarrhalis * GC6907 (Clinical)
>64
64
16
32
16
19
H. influenzae <> GC6896 (ATCC Control)
>64
>64
>64
>64
>64
20
C. albicans GC3066 ATCC (Control)
>64
>64
>64
>64
>64
[0000]
TABLE VII
ANTIBACTERIAL ACTIVITY OF (7-SUBSTITUTED)-8-(SUBSTITUTED)-9-(SUBSTITUTED)-TETRACYCLINES
MIC (μg/ml) COMPOUND
Example 32
Example 33
Example 34
Example 35
Example 36
1
E. coli GC2270 (tet(M))
>64
>64
>64
16
4
2
E. coli GC4559 (parent GC4560)
>64
>64
>64
8
4
3
E. coli GC4560 (IMP mutant)
>64
16
32
0.50
1
4
E. coli GC2203 (ATCC Control)
>64
64
>64
4
2
5
E. coli GC1073 (tet(B))
>64
>64
>64
32
4
6
S. aureus GC1131 (Clinical)
>64
16
32
0.50
4
7
S. aureus GC6466 (tet(M))
>64
32
64
1
4
8
S. aureus GC6467 (tet(M) + (K))
>64
32
64
8
16
9
S. aureus GC1079 (tet(K))
>64
16
32
4
4
10
S. aureus GC4536 (Smith MP -In Vivo)
>64
16
64
1
4
11
S. aureus GC2216 (ATCC Control)
>64
16
32
0.50
2
12
E. faecalis GC4555 (ATCC Control)
64
16
32
1
4
13
E. faecalis GC2267 (tet(L) + (M) + (S))
>64
16
32
4
4
14
E. faecalis GC2242 (Van-resistant)
64
16
32
1
4
15
S. pneumoniae * GC4465 (Clinical)
16
16
32
0.50
1
16
S. pneumoniae * GC1894 (Clinical)
8
32
64
0.25
1
17
S. pyogenes * GC4563 (Clinical)
16
8
32
0.25
1
18
M. catarrhalis * GC6907 (Clinical)
32
8
16
0.50
1
19
H. influenzae <> GC6896 (ATCC Control)
>64
32
>64
2
4
20
C. albicans GC3066 ATCC (Control)
>64
>64
>64
>64
>64
[0000]
TABLE VIII
ANTIBACTERIAL ACTIVITY OF (7-SUBSTITUTED)-8-
(SUBSTITUTED)-9-(SUBSTITUTED)-TETRACYCLINES
MIC (μg/ml) COMPOUND
Exam-
Exam-
Exam-
ple 37
ple 38
ple 39
1
E. coli GC2270 (tet(M))
4
32
32
2
E. coli GC4559 (parent GC4560)
2
32
32
3
E. coli GC4560 (IMP mutant)
1
8
8
4
E. coli GC2203 (ATCC Control)
2
32
32
5
E. coli GC1073 (tet(B))
2
32
32
6
S. aureus GC1131 (Clinical)
4
32
32
7
S. aureus GC6466 (tet(M))
4
32
32
8
S. aureus GC6467 (tet(M) + (K))
8
>64
>64
9
S. aureus GC1079 (tet(K))
4
64
64
10
S. aureus GC4536 (Smith MP -In
4
16
32
Vivo)
11
S. aureus GC2216 (ATCC Control)
4
32
32
12
E. faecalis GC4555 (ATCC Control)
2
16
32
13
E. faecalis GC2267 (tet(L) + (M) + (S))
4
64
64
14
E. faecalis GC2242 (Van-resistant)
2
16
32
15
S. pneumoniae * GC4465 (Clinical)
1
4
8
16
S. pneumoniae * GC1894 (Clinical)
1
4
8
17
S. pyogenes * GC4563 (Clinical)
1
4
8
18
M. catarrhalis * GC6907 (Clinical)
1
4
8
19
H. influenzae <> GC6896 (ATCC
4
64
64
Control)
20
C. albicans GC3066 ATCC (Control)
>64
>64
>64
[0097] When the compounds of the invention are employed as antibacterials, they can be combined with one or more pharmaceutically acceptable carriers, for example, solvents, diluents and the like, and may be administered orally in such forms as tablets, capsules, dispersible powders, granules, or suspensions containing, for example, from about 0.05 to 5% of suspending agent, syrups containing, for example, from about 10 to 50% of sugar, and elixirs containing, for example, from about 20 to 50% ethanol, and the like, or parenterally in the form of sterile injectable solutions or suspensions containing from about 0.05 to 5% suspending agent in an isotonic medium. Such pharmaceutical preparations may contain, for example, from about 25 to about 90% of the active ingredient in combination with the carrier, more usually between about 5% and 60% by weight.
[0098] An effective amount of compound from about 2.0 mg/kg of body weight to about 100.0 mg/kg of body weight may be administered one to five times per day via any typical route of administration including but not limited to oral, parenteral (including subcutaneous, intravenous, intramuscular, intrasternal injection or infusion techniques), topical or rectal, in dosage unit formulations containing conventional non-toxic pharmaceutically acceptable carriers, adjuvants and vehicles. It will be understood, however, that the specific dose level and frequency of dosage for any particular patient may be varied and will depend upon a variety of factors including the activity of the specific compound employed, the metabolic stability and length of action of that compound, the age, body weight, general health, sex, diet, mode and time of administration, rate of excretion, drug combination, the severity of the particular condition, and the host undergoing therapy.
[0099] These active compounds may be administered orally as well as by intravenous, intramuscular, or subcutaneous routes. Solid carriers include starch, lactose, dicalcium phosphate, microcrystalline cellulose, sucrose and kaolin, while liquid carriers include sterile water, polyethylene glycols, non-ionic surfactants and edible oils such as corn, peanut and sesame oils, as are appropriate to the nature of the active ingredient and the particular form of administration desired. Adjuvants customarily employed in the preparation of pharmaceutical compositions may be advantageously included, such as flavoring agents, coloring agents, preserving agents, and antioxidants, for example, vitamin E, ascorbic acid, BHT and BHA. The preferred pharmaceutical compositions of compounds of the invention from the standpoint of ease of preparation and administration are solid compositions, particularly tablets and hard-filled or liquid-filled capsules. Oral administration of the compounds is preferred.
[0100] These active compounds may also be administered parenterally or intraperitoneally. Solutions or suspensions of these active compounds as a free base or pharmacologically acceptable salt can be prepared in water suitably mixed with a surfactant such as hydroxy-propylcellulose. Dispersions can also be prepared in glycerol, liquid, polyethylene glycols and mixtures thereof in oils. Under ordinary conditions of storage and use, these preparations contain a preservative to prevent the growth of microorganisms.
[0101] The pharmaceutical forms suitable for injectable use include sterile aqueous solutions or dispersions and sterile powders for the extemporaneous preparation of sterile injectable solutions or dispersions. In all cases, the form must be sterile and must be fluid to the extent that easy syringability exists. it must be stable under the conditions of manufacture and storage and must be preserved against the contaminating action of microorganisms such as bacterial and fungi. The carrier can be a solvent or dispersion medium containing, for example, water, ethanol, polyol (e.g., glycerol, propylene glycol and liquid polyethylene glycol), suitable mixtures thereof, and vegetable oil.
[0102] The invention will be more fully described in conjunction with the following specific examples which are not to be construed as limiting the scope of the invention.
Example of Procedure A
Example 1
(6aR,7aS,8S,11aS)-5,8-bis(dimethylamino)-2-(2,2-diphenylvinyl)-9,11a,12-trihydroxy-11,13-dioxo-6,6a,7,7a,8,11,11a,13-octahydrotetraceno[2,1-d][1,3]oxazole-10-carboxamide
[0103]
[0104] 9-aminominocycline sulfate salt (0.500 g, 0.748 mmol) is dissolved in anhydrous DMF and treated with β-phenylcinnamaldehyde (0.779 g, 3.74 mmol, 5 equivalents) The solution is then treated with DDQ (0.085 g, 0.374 mmol, 0.5 equivalents) and stirred at room temperature for 5 min. ES+ mass spectrometry showed a 1:1 ratio of product and starting material. A second portion of DDQ (0.068 g, 0.300 mmol, 0.4 equivalents) is added. After approximately 5 minutes, acetonitrile (7.5 mL) is added, and the entire reaction mixture is poured slowly into ether (750 mL.) The pink solid is removed by filtration and washed with fresh ether to yield 0.480 g of the crude product. This material is dissolved in water (75 mL) to give a solution at pH 2.2, which is extracted with dichloromethane (2×100 mL.) The pH of the aqueous layer is raised to 3.0 with aqueous ammonia, and the solution is again extracted with dichloromethane (2×100 mL.) The four organic extracts are dried (Na 2 SO 4 ), filtered and concentrated to a volume of about 2 mL. A small portion of methanol (1 mL) is added, and the concentrated solution is treated dropwise with 1 M HCl in ether. The solid precipitate is filtered, washed with fresh ether and dried under vacuum the product as its HCl salt.
[0105] Selected 1 H NMR signals: δ 4.26 (s, 1H), 7.13 (s, 1H), 7.26-7.45 (m, 8H), 7.63 (s, 1H), 9.08 (s, 1H), 9.54 (s, 1H).
[0106] The compounds of this invention listed below in Examples 2 to 37 are prepared substantially following the method described in detail hereinabove in Example 1 using procedure A.
Example 2
(7aS,8S,11aS)-8-(dimethylamino)-9,11a,13-trihydroxy-2-(2-methyl-1-propenyl)-11,12-dioxo-7,7a,8,11,11a,12-hexahydronaphthaceno[2,1-d][1,3]oxazole-10-carboxamide
[0107]
[0108] MS m/z 492 (M+H)
[0109] HRMS: calcd for C 26 H 26 N 3 O 7 , 491.16925; found (ESI+), 492.1765
Example 3
(7aS,8S,11aS)-8-(dimethylamino)-2-[4-(dimethylamino)phenyl]-9,11a,13-trihydroxy-11,12-dioxo-7,7a,8,11,11a,12-hexahydronaphthaceno[2,1-d][1,3]oxazole-10-carboxamide
[0110]
[0111] HRMS: calcd for C 30 H 29 N 3 O 7 , 566.1958; found (ESI+), 557.2030
Example 4
(6aR,7aS,8S,11aS)-2-tert-butyl-5,8-bis(dimethylamino)-9,11a,12-trihydroxy-11,13-dioxo-6,6a,7,7a,8,11,11a,13-octahydrotetraceno[2,1-d][1,3]oxazole-10-carboxamide
[0112]
[0113] MS (ESI) m/z 539.3 (M+H);
[0114] MS (ESI) m/z 270.4 (M+2H);
[0115] HRMS: calcd for C 2 H 34 N<O 7 .HCl, 574.2194; found (ESI−), 537.23462;
Example 5
(6aR,7aS,8S,11aS)-5,8-bis(dimethylamino)-9,11a,12-trihydroxy-2-(4-methylphenyl)-11,13-dioxo-6,6a,7,7a,8,11,11a,13-octahydrotetraceno[2,1-d][1,3]oxazole-10-carboxamide
[0116]
[0117] MS (ESI) m/z 573.3 (M+H);
[0118] MS (ESI) m/z 287 (M+2H);
[0119] HRMS: calcd for C 31 H 32 N 4 O 7 .HCl, 608.2038; found (ESI−), 571.21905;
Example 6
(7aS,8S,11aS)-5,8-bis(dimethylamino)-2-(3-fluorophenyl)-9,11a,13-trihydroxy-11,12-dioxo-7,7a,8,11,11a,12-hexahydrotetraceno[2,1-d][1,3]oxazole-10-carboxamide
[0120]
Example 7
(6aR,7aS,8S,11aS)-2-(4-cyanophenyl)-5,8-bis(dimethylamino)-9,11a,12-trihydroxy-11,13-dioxo-6,6a,7,7a,8,11,11a,13-octahydrotetraceno[2,1-d][1,3]oxazole-10-carboxamide
[0121]
[0122] MS (ESI) m/z 584.4 (M+H);
[0123] HRMS: calcd for C 31 H 29 N 5 O 7 .HCl, 619.1834; found (ESI−), 582.19817;
Example 8
(6aR,7aS,8S,11aS)-5,8-bis(dimethylamino)-2-[4-(dimethylamino)phenyl]-9,11a,12-trihydroxy-11,13-dioxo-6,6a,7,7a,8,11,11a,13-octahydrotetraceno[2,1-d][1,3]oxazole-10-carboxamide
[0124]
[0125] MS (ESI) m/z 602.2 (M+H);
[0126] MS (ESI) m/z 301.8 (M+2H);
[0127] HRMS: calcd for C 32 H 35 N 5 O 7 .HCl, 637.2303; found (ESI−), 600.24521;
Example 9
(6aR,7aS,8S,11aS)-5,8-bis(dimethylamino)-2-(2,2-diphenylvinyl)-9,11a,12-trihydroxy-11,13-dioxo-6,6a,7,7a,8,1111a,13-octahydrotetraceno[2,1-d][1,3]oxazole-10-carboxamide
[0128]
[0129] MS (ESI) m/z 661.3 (M+H);
[0130] MS (ESI) m/z 331.3 (M+2H);
[0131] HRMS: calcd for C 38 H 36 N 4 O 7 .HCl, 696.2351; found (ESI−), 659.24957;
Example 10
(6aR,7aS,8S,11aS)-2-(5-tert-butyl-2-hydroxyphenyl)-5,8-bis(dimethylamino)-9,11a,12-trihydroxy-11,13-dioxo-6,6a,7,7a,8,11,11a,13-octahydrotetraceno[2,1-d][1,3]oxazole-10-carboxamide
[0132]
[0133] MS (ESI) m/z 631.4 (M+H);
[0134] HRMS: calcd for C 34 H 38 N 4 O 8 .HCl, 666.2456; found (ESI+), 631.27753;
Example 11
(6aR,7aS,8S,11aS)-2-[4-(benzyloxy)phenyl]-5,8-bis(dimethylamino)-9,11a,12-trihydroxy-11,13-dioxo-6,6a,7,7a,8,11,11a,13-octahydrotetraceno[2,1-d][1,3]oxazole-10-carboxamide
[0135]
[0136] MS (ESI) m/z 665.2 (M+H);
[0137] HRMS: calcd for C 37 H 36 N 4 O 8 .HCl, 700.2300; found (ESI+), 665.26096;
Example 12
(6aR,7aS,8S,11aS)-2-(2,4-dihydroxyphenyl)-5,8-bis(dimethylamino)-9,11a,12-trihydroxy-11,13-dioxo-6,6a,7,7a,8,11,11a,13-octahydrotetraceno[2,1-d][1,3]oxazole-10-carboxamide
[0138]
[0139] MS (ESI) m/z 591.2 (M+H);
[0140] HRMS: calcd for C 30 H 30 N 4 O 9 .HCl, 626.1780; found (ESI−), 589.1927;
Example 13
(6aR,7aS,8S,11aS)-5,8-bis(dimethylamino)-2-(3-fluoro-4-methoxyphenyl)-9,11a,12-trihydroxy-11,13-dioxo-6,6a,7,7a,8,11,11a,13-octahydrotetraceno[2,1-d][1,3]oxazole-10-carboxamide
[0141]
[0142] MS (ESI) m/z 607.3 (M+H);
[0143] MS (ESI) m/z 304 (M+2H);
[0144] HRMS: calcd for C 31 H 31 FN 4 O 8 .HCl, 642.1893; found (ESI−), 605.20519;
Example 14
(6aR,7aS,8S,11aS)-2-(1,3-benzodioxol-5-yl)-5,8-bis(dimethylamino)-9,11a,12-trihydroxy-11,13-dioxo-6,6a,7,7a,8,11,11a,13-octahydrotetraceno[2,1-d][1,3]oxazole-10-carboxamide
[0145]
[0146] MS (ESI) m/z 603.3 (M+H);
[0147] MS (ESI) m/z 302.1 (M+2H);
[0148] HRMS: calcd for C 31 H 30 N 4 O 9 .HCl, 638.1780; found (ESI+), 603.20953;
Example 15
(6aR,7aS,8S,11aS)-5,8-bis(dimethylamino)-9,11a,12-trihydroxy-11,13-dioxo-2-(2,4,6-trimethoxyphenyl)-6,6a,7,7a,8,11,11a,13-octahydrotetraceno[2,1-d][1,3]oxazole-10-carboxamide
[0149]
[0150] MS (ESI) m/z 649.2 (M+H);
[0151] HRMS: calcd for C 33 H 36 N 4 O 10 .HCl, 684.2198; found (ESI−), 647.23441;
Example 16
(6aR,7aS,8S,11aS)-5,8-bis(dimethylamino)-9,11a,12-trihydroxy-1,13-dioxo-2-(2,4,5-triethoxyphenyl)-6,6a,7,7a,8,11,11a,13-octahydrotetraceno[2,1-d][1,3]oxazole-10-carboxamide
[0152]
[0153] MS (ESI) m/z 691.3 (M+H);
[0154] HRMS: calcd for C 3 H 42 N 4 O 1 .HCl, 726.2668; found (ESI+), 691.29817;
Example 17
(6aR,7aS,8S,11aS)-5,8-bis(dimethylamino)-9,11a,12-trihydroxy-11,13-dioxo-2-thien-3-yl-6,6a,7,7a,8,11,11a,13-octahydrotetraceno[2,1-d][1,3]oxazole-10-carboxamide
[0155]
[0156] MS (ESI) m/z 565.2 (M+H);
[0157] MS (ESI) m/z 283.4 (M+2H);
[0158] HRMS: calcd for C 28 H 28 N 4 O 7 S.HCl, 600.1445; found (ESI−), 563.15992;
Example 18
(6aR,7aS,8S,11aS)-2-(1-benzofuran-2-yl)-5,8-bis(dimethylamino)-9,11a,12-trihydroxy-11,13-dioxo-6,6a,7,7a,8,11,11a,13-octahydrotetraceno[2,1-d][1,3]oxazole-10-carboxamide
[0159]
[0160] MS (ESI) m/z 599.3 (M+H);
[0161] HRMS: calcd for C 32 H 30 N 4 O 8 .HCl, 634.1830; found (ESI−), 597.19811;
Example 19
(6aR,7aS,8S,11aS)-5,8-bis(dimethylamino)-9,11a,12-trihydroxy-2-(1-methyl-1H-indol-2-yl)-11,13-dioxo-6,6a,7,7a,8,11,11a,13-octahydrotetraceno[2,1-d][1,3]oxazole-10-carboxamide
[0162]
[0163] MS (ESI) m/z 612.2 (M+H);
[0164] HRMS: calcd for C 33 H 33 N 5 O 7 .HCl, 647.2147; found (ESI+), 612.24406;
Example 20
(6aR,7aS,8S,11aS)-5,8-bis(dimethylamino)-2-(2-furyl)-9,11a,12-trihydroxy-11,13-dioxo-6,6a,7,7a,8,11,11a,13-octahydrotetraceno[2,1-d][1,3]oxazole-10-carboxamide
[0165]
[0166] MS (ESI) m/z 549.3 (M+H);
[0167] HRMS: calcd for C 1 H 2 N 4 O 8 .HCl, 584.1674; found (ESI−), 547.1822;
Example 21
{5-[(6aR,7aS,8S,11aS)-10-(aminocarbonyl)-5,8-bis(dimethylamino)-9,11a,12-trihydroxy-11,13-dioxo-6,6a,7,7a,8,11,11a,13-octahydrotetraceno[2,1-d][1,3]oxazol-2-yl]-2-furyl}methyl acetate
[0168]
[0169] MS (ESI) m/z 621.2 (M+H);
[0170] HRMS: calcd for C 31 H 32 N 4 O 10 .HCl, 656.1885; found (ESI+), 621.21807;
Example 22
(6aR,7aS,8S,11aS)-5,8-bis(dimethylamino)-2-[(E)-2-(2-furyl)ethenyl]-9,11a,12-trihydroxy-11,13-dioxo-6,6a,7,7a,8,11,11a,13-octahydrotetraceno[2,1-d][1,3]oxazole-10-carboxamide
[0171]
[0172] MS (ESI) m/z 575.2 (M+H);
[0173] MS (ESI) m/z 288.3 (M+2H);
[0174] HRMS: calcd for C 30 H 30 N 4 O 8 .HCl, 610.1830; found (ESI−), 573.1985;
Example 23
(6aR,7aS,8S,11aS)-2-(1-benzothien-3-yl)-5,8-bis(dimethylamino)-9,11a,12-trihydroxy-11,13-dioxo-6,6a,7,7a,8,11,11a,13-octahydrotetraceno[2,1-d][1,3]oxazole-10-carboxamide
[0175]
[0176] MS (ESI+) m/z 615.1 ((M+H) + );
[0177] HRMS: calcd for C 32 H 30 N 4 O 7 S.HCl, 650.1602; found (ESI+), 615.19036;
Example 24
(6aR,7aS,8S,11aS)-5,8-bis(dimethylamino)-9,11a,12-trihydroxy-11,13-dioxo-2-(1,3-thiazol-2-yl)-6,6a,7,7a,8,11,11a,13-octahydrotetraceno[2,1-d][1,3]oxazole-10-carboxamide
[0178]
[0179] MS (ESI) m/z 566.4 (M+H);
[0180] MS (ESI) m/z 283.6 (M+2H);
[0181] HRMS: calcd for C 27 H 27 N 5 O 7 S.HCl, 601.1398; found (ESI+), 566.16973;
Example 25
(6aR,7aS,8S,11aS)-5,8-bis(dimethylamino)-9,11a,12-trihydroxy-11,13-dioxo-2-[(E)-2-phenylethenyl]-6,6a,7,7a,8,11,11a,13-octahydrotetraceno[2,1-d][1,3]oxazole-10-carboxamide
[0182]
[0183] MS (ESI) m/z 585.4 (M+H);
[0184] MS (ESI) m/z 293.3 (M+2H);
[0185] HRMS: calcd for C 32 H 32 N 4 O 7 .HCl, 620.2038; found (ESI+), 585.2329;
Example 26
(6aR,7aS,8S,11aS)-5,8-bis(dimethylamino)-9,11a,12-trihydroxy-2-[(E)-2-(4-methoxyphenyl)ethenyl]-11,13-dioxo-6,6a,7,7a,8,11,11a,13-octahydrotetraceno[2,1-d][1,3]oxazole-10-carboxamide
[0186]
[0187] MS (ESI) m/z 615.3 (M+H);
[0188] MS (ESI) m/z 308.3 (M+2H);
[0189] HRMS: calcd for C 33 H 34 N 4 O 8 .HCl, 650.2143; found (ESI+), 615.24413;
Example 27
(6aR,7aS,8S,11aS)-5,8-bis(dimethylamino)-9,11a,12-trihydroxy-2-[(E)-2-(3-methoxyphenyl)ethenyl]-11,13-dioxo-6,6a,7,7a,8,11,11a,13-octahydrotetraceno[2,1-d][1,3]oxazole-10-carboxamide
[0190]
[0191] MS (ESI) m/z 615.4 (M+H);
[0192] MS (ESI) m/z 308.3 (M+2H);
[0193] HRMS: calcd for C 33 H 34 N 4 O 8 .HCl, 650.2143; found (ESI+), 615.24419;
Example 28
(6aR,7aS,8S,11aS)-5,8-bis(dimethylamino)-9,11a,12-trihydroxy-2-[(E)-2-(2-methoxyphenyl)ethenyl]-11,13-dioxo-6,6a,7,7a,8,11,11a,13-octahydrotetraceno[2,1-d][1,3]oxazole-10-carboxamide
[0194]
[0195] MS (ESI) m/z 615.3 (M+H);
[0196] MS (ESI) m/z 308.3 (M+2H);
[0197] HRMS: calcd for C 3 H 34 N 4 O 8 .HCl, 650.2143; found (ESI+), 615.24408;
Example 29
(6aR,7aS,8S,11aS)-5,8-bis(dimethylamino)-2-[(E)-2-(4-fluorophenyl)ethenyl]-9,11a,12-trihydroxy-11,13-dioxo-6,6a,7,7a,8,11,11a,13-octahydrotetraceno[2,1-d][1,3]oxazole-10-carboxamide
[0198]
[0199] MS (ESI) m/z 603.3 (M+H);
[0200] MS (ESI) m/z 302.3 (M+2H);
[0201] HRMS: calcd for C 32 H 31 FN 4 O 7 .HCl, 638.1944; found (ESI+), 603.22476;
Example 30
(6aR,7aS,8S,11aS)-5,8-bis(dimethylamino)-2-[(E)-2-(2-fluorophenyl)ethenyl]-9,11a,12-trihydroxy-11,13-dioxo-6,6a,7,7a,8,11,11a,13-octahydrotetraceno[2,1-d][1,3]oxazole-10-carboxamide
[0202]
[0203] MS (ESI) m/z 603.2 (M+H);
[0204] MS (ESI) m/z 302.3 (M+2H);
[0205] HRMS: calcd for C 32 H 31 FN 4 O 7 .HCl, 638.1944; found (ESI+), 603.22469;
Example 31
(6aR,7aS,8S,11aS)-2-(4-tert-butylphenyl)-5,8-bis(dimethylamino)-9,11a,12-trihydroxy-11,13-dioxo-6,6a,7,7a,8,11,11a,13-octahydrotetraceno[2,1-d][1,3]oxazole-10-carboxamide
[0206]
[0207] MS (ESI) m/z 615.3 (M+H);
[0208] MS (ESI) m/z 308.3 (M+2H);
[0209] HRMS: calcd for C 34 H 38 N 4 O 7 .HCl, 650.2507; found (ESI+), 615.28057;
Example 32
(6aR,7aS,8S,1aS)-5,8-bis(dimethylamino)-2-[4-(hexyloxy)phenyl]-9,11a,12-trihydroxy-11,13-dioxo-6,6a,7,7a,8,11,11a,13-octahydrotetraceno[2,1-d][1,3]oxazole-10-carboxamide
[0210]
[0211] MS (ESI) m/z 659.4 (M+H);
[0212] MS (ESI) m/z 330.4 (M+2H);
[0213] HRMS: calcd for C 36 H 42 N 4 O 8 .HCl, 694.2769; found (ESI+), 659.30693;
Example 33
(6aR,7aS,8S,11aS)-5,8-bis(dimethylamino)-9,11a,12-trihydroxy-11,13-dioxo-2-pyridin-4-yl-6,6a,7,7a,8,11,11a,13-octahydrotetraceno[2,1-d][1,3]oxazole-10-carboxamide
[0214]
Example 34
(6aR,7aS,8S,11aS)-5,8-bis(dimethylamino)-9,11a,12-trihydroxy-11,13-dioxo-2-pyridin-3-yl-6,6a,7,7a,8,11,11a,13-octahydrotetraceno[2,1-d][1,3]oxazole-10-carboxamide
[0215]
[0216] MS (ESI) m/z 560.3 (M+H);
[0217] MS (ESI) m/z 280.7 (M+2H);
[0218] HRMS: calcd for C 29 H 29 N 5 O 7 .HCl, 595.1834; found (ESI+), 560.21353;
Example 35
(6aR,7aS,8S,11aS)-2-(chloromethyl)-5,8-bis(dimethylamino)-9,11a,12-trihydroxy-11,13-dioxo-6,6a,7,7a,8,11,11a,13-octahydrotetraceno[2,1-d][1,3]oxazole-10-carboxamide
[0219]
[0220] MS (ESI) m/z 531.2 (M+H);
[0221] MS (ESI) m/z 266.3 (M+2H);
Example 36
(6aR,7aS,8S,11aS)-5,8-bis(dimethylamino)-2-[(dimethylamino)methyl]-9,11a,12-trihydroxy-11,13-dioxo-6,6a,7,7a,8,11,11a,13-octahydrotetraceno[2,1-d][1,3]oxazole-10-carboxamide
[0222]
[0223] MS (ESI) m/z 540.4 (M+H);
[0224] MS (ESI) m/z 270.7 (M+2H);
[0225] HRMS: calcd for C 27 H 33 N 5 O 7 .HCl, 575.2147; found (ESI+), 540.24506;
Example 37
(6aR,7aS,8S,11aS)-5,8-bis(dimethylamino)-9,11a,12-trihydroxy-11,13-dioxo-2-(pyrrolidin-1-ylmethyl)-6,6a,7,7a,8,11,11a,13-octahydrotetraceno[2,1-d][1,3]oxazole-10-carboxamide
[0226]
[0227] MS (ESI) m/z 566.4 (M+H);
[0228] MS (ESI) m/z 283.9 (M+2H);
[0229] HRMS: calcd for C 29 H 35 N 5 O 7 .HCl, 601.2303; found (ESI+), 566.26066;
Example of Procedure B
Example 38
(6aR,7aS,8S,11aS)-5,8-bis(dimethylamino)-9,11a,12-trihydroxy-11,13-dioxo-2-[(propylamino)methyl]-6,6a,7,7a,8,11,11a,13-octahydrotetraceno[2,1-d][1,3]oxazole-10-carboxamide
[0230]
[0231] 9-aminominocycline sulfate salt (1.0 g, 1.50 mmol) is dissolved in DMF (50 mL) and treated with a solution of 2-chloro-1,1,1-trimethoxyethane (0.463 g, 3.00 mmol, 2 equivalents). The reaction is stirred at room temperature until mass spectrometry shows conversion to the chloromethylbenzoxazole derivative. The solution is then treated with n-propylamine (10 mL, excess) and stirred until mass spectrometry shows conversion to the n-propylaminomethyl benzoxazole. The mixture is concentrated under reduced pressure to remove excess n-propylamine, and then poured slowly into ether (1 L) and HCl/ether is added to precipate the salt. The solid is rinsed with fresh ether and dried under vacuum. The crude solid is dissolved in water (100 mL) giving a solution at pH 2. The pH is raised successively by 0.5 units with aqueous ammonia, and extracted with dichloromethane. The fractions extracted at pH 4-4.5 are combined, dried (Na 2 SO 4 ), filtered and concentrated nearly to dryness. A small volume of methanol is added and the solution is treated with 1 M HCl in ether. The precipitated solid is collected by filtration, washed with fresh ether and dried under vacuum to yield 0.067 g of the product as its HCl salt.
[0232] Selected 1 H NMR signals: δ 0.94 (t, 3H), 1.73 (m, 2H), 4.31 (s, 1H), 4.65 (s, 2H), 7.78 (s, 1H), 9.15 (s, 1H), 9.67 (s, 1H).
[0233] The compounds of this invention listed below in Examples 39 to 41 are prepared substantially following the method described in detail hereinabove in Example 38 using procedure B.
Prepared from Procedure B
Example 39
(6aR,7aS,8S,11aS)-2-[(butylamino)methyl]-5,8-bis(dimethylamino)-9,11a,12-trihydroxy-11,13-dioxo-6,6a,7,7a,8,11,11a,13-octahydrotetraceno[2,1-d][1,3]oxazole-10-carboxamide
[0234]
[0235] MS (ESI) m/z 568.3 (M+H);
[0236] MS (ESI) m/z 284.8 (M+2H);
[0237] MS (ESI) m/z 305.2 (M+ACN+2H);
[0238] HRMS: calcd for C 29 H 37 N 5 O 7 .HCl, 603.2460; found (ESI+), 568.27616;
Procedure B
Example 40
(6aR,7aS,8S,11aS)-5,8-bis(dimethylamino)-9,11a,12-trihydroxy-11,13-dioxo-2-[(propylamino)methyl]-6,6a,7,7a,8,11,11a,13-octahydrotetraceno[2,1-d][1,3]oxazole-10-carboxamide
[0239]
[0240] MS (ESI) m/z 554.3 (M+H);
[0241] MS (ESI) m/z 277.7 (M+2H);
[0242] HRMS: calcd for C 28 H 35 N 5 O 7 .HCl, 589.2303; found (ESI+), 554.2604;
Procedure B
Example 41
(6aR,7aS,8S,11aS)-2-[(tert-butylamino)methyl]-5,8-bis(dimethylamino)-9,11a,12-trihydroxy-11,13-dioxo-6,6a,7,7a,8,11,11a,13-octahydrotetraceno[2,1-d][1,3]oxazole-10-carboxamide
[0243]
[0244] 9-aminominocycline sulfate salt (1.0 g, 1.50 mmol) is dissolved DMF (20 mL) and treated with a solution of 2-chlorotrimethoxyethane (0.35 g, 2.2 mmol, 1.46 equivalents). The reaction is stirred at room temperature until mass spectrometry showed conversion to the chloromethylbenzoxazole derivative. The solution is then treated with t-butylamine (7.3 mL, excess) and stirred until mass spectrometry showed conversion to the t-butylaminomethyl benzoxazole. The mixture is concentrated under reduced pressure to remove excess t-butylamine, and then poured slowly into ether (1 L) and HCl/ether is added to precipate the salt. The solid is rinsed with fresh ether and dried under vacuum. The crude solid is dissolved in water (100 mL) giving a solution at pH 2. The pH is raised successively by 0.5 units with aqueous ammonia, and extracted with dichloromethane. The fractions extracted at pH 4-4.5 are combined, dried (Na 2 SO 4 ), filtered and concentrated nearly to dryness. A small volume of methanol is added and the solution is treated with 1 M HCl in ether. The precipitated solid is collected by filtration, washed with fresh ether and dried under vacuum to give the product as its HCl salt.
[0245] MS (ESI+) m/z 568.4 ((M+H)+);
[0246] MS (ESI+) m/z 284.9 ((M+2H)2+);
[0247] MS (ESI+) m/z 146.3 ((M′+H)+);
[0248] HRMS: calcd for C 29 H 37 N 5 O 7 .HCl, 603.2460; found (ESI−), 566.26087;
Example of Procedure C
Example 42
(6aR,7aS,8S,11aS)-5,8-bis(dimethylamino)-9,11a,12-trihydroxy-11,13-dioxo-2-thioxo-2,3,6,6a,7,7a,8,11,11a,13-decahydrotetraceno[2,1-d][1,3]oxazole-10-carboxamide
[0249]
[0250] To a solution of 9-amino-mino disulfate (0.668 g, 1 mmol) in DMSO (30 mL) is added 2 equivalents of 1,1-thiocarbonyldiimidazole. The reaction is then stirred at room temperature for 2 to 12 hr (followed by MS (ES)). The mixture then triturated with diethyl ether and the solid collected. Material is used in the next step without further purification.
[0251] MS (ESI) m/z 515.2 (M+H);
[0252] HRMS: calcd for C 24 H 26 N 4 O 7 S.H 2 SO 4 , 612.1196; found (ESI+), 515.15934;
[0253] The compounds of this invention listed below in Examples 43 to 44 are prepared substantially following the method described in detail hereinabove in Example 42 using procedure C.
Example of Procedure C
Procedure C
Example 43
benzyl {[(6aR,7aS,8S,11aS)-10-(aminocarbonyl)-5,8-bis(dimethylamino)-9,11a,12-trihydroxy-11,13-dioxo-6,6a,7,7a,8,11,11a,13-octahydrotetraceno[2,1-d][1,3]oxazol-2-yl]thio}acetate
[0254]
[0255] To a solution of (6aR,7aS,8S,11aS)-5,8-bis(dimethylamino)-9,11a,12-trihydroxy-11,13-dioxo-2-thioxo-2,3,6,6a,7,7a,8,11,11a,13-decahydrotetraceno[2,1-d][1,3]oxazole-10-carboxamide (Example 42) in N,N-dimethylformamide (DMF) is added 2 equivalents of diisopropylethylamine, after stirring for 5 min. 1.2 equivalent of benzyl-2-bromoacetate is added. The reaction mixture is stirred for 1 hr and mixture triturated with diethyl ether and solid is collected. It is purified by extraction.
[0256] MS (ESI) m/z 663.2 (M+H);
[0257] MS (ESI) m/z 332.1 (M+2H);
[0258] HRMS: calcd for C 33 H 34 N 4 O 9 S.HCl, 698.1813; found (ESI+), 663.2115;
Example 44
(6aR,7aS,8S,11aS)-5,8-bis(dimethylamino)-2-[(4-fluorobenzyl)thio]-9,11a,12-trihydroxy-11,13-dioxo-6,6a,7,7a,8,11,11a,13-octahydrotetraceno[2,1-d][1,3]oxazole-10-carboxamide
[0259]
[0260] The compound of the example is prepared using procedure D in Example 43 using 4-fluorobenzylbromide.
[0261] MS (ESI) m/z 622.9 (M+H);
[0262] HRMS: calcd for C 31 H 31 FN 4 O 7 S.HCl, 658.1664; found (ESI+), 623.19689;
Example of Procedure D
Compound 1 to 4 to 6
Example 45
[4S-(4α,4aα,5aα, 12aα)]-4,7-Bis(dimethylamino)-9-[2-(1,1-dimethylethylamino)acetylamino]-1,4,4a,5,5a,6,11,12a-octahydro-3,10,12,12a-tetrahydroxy-1,11-dioxo-2-naphthacenecarboxamide. (mono HCl); (free base)
[0263]
[0264] 9-aminominocycline sulfate salt (1.0 g, 1.50 mmol) is dissolved DMF (20 mL) and treated with a solution of 2-chlorotrimethoxyethane (0.35 g, 2.2 mmol, 1.47 equivalents). The reaction is stirred at room temperature until mass spectrometry showed conversion to the chloromethylbenzoxazole derivative. The solution is then treated with t-butylamine (7.3 mL, excess) and stirred until mass spectrometry showed conversion to the t-butylaminomethyl benzoxazole. The mixture is concentrated under reduced pressure to remove excess t-butylamine, and then poured slowly into ether (1 L) and HCl/ether is added to precipate the salt. The solid is rinsed with fresh ether and dried under vacuum. The crude solid is dissolved in water (100 mL) giving a solution at pH 2. The pH is raised successively by 0.5 units with aqueous ammonia, and extracted with dichloromethane. The fractions extracted at pH 4-4.5 are combined, dried (Na 2 SO 4 ), filtered and concentrated nearly to dryness. A small volume of methanol is added and the solution is treated with 1 M HCl in ether. The precipitated solid is collected by filtration, washed with fresh ether and dried under vacuum to give the product as its HCl salt.
[0265] Product from example 41 is treated with aqueous acid for one hour to 24 hour to give mono HCL salt of example 45
[0266] MS (ESI+) m/z 586.4 ((M+H)+;
[0267] The following examples are prepared using similar method described in procedure D.
Example 46
[4S-(4α,4aα,5aα,12aα)]-4,7-Bis(dimethylamino)-9-[(dimethyamino)acetylamino]-1,4,4a,5,5a,6,11,12a-octahydro-3,10,12,12a-tetrahydroxy-1,11-dioxo-2-naphthacenecarboxamide
[0268]
[0269] MS (FAB) m/z 558 ((M+H)+;
Example 47
[4S-(4α,4aα,5aα,12aα)]-4,7-Bis(dimethylamino)-9-[[(n-butylamino)acetyl]amino]-1,4,4a,5,5a,6,11,12a-octahydro-3,10,12,12a-tetrahydroxy-1,11-dioxo-2-naphthacenecarboxamide
[0270]
[0271] MS (FAB) m/z 586 ((M+H)+;
Example 48
[4S-(4α,4aα,5aα,12aα)]-4,7-Bis(dimethylamino)-9-[[(propylamino)acetyl]amino]-1,4,4a,5,5a,6,11,12a-octahydro-3,10,12,12a-tetrahydroxy-1,11-dioxo-2-naphthacenecarboxamide
[0272]
[0273] MS (FAB) m/z 572 ((M+H)+;
Example 49
[4S-(4α,4aα,5aα,12aα)]-4,7-Bis(dimethylamino)-9-[(chloroacetyl)amino]-1,4,4a,5,5a,6,11,12a-octahydro-3,10,12,12a-tetrahydroxy-1,11-dioxo-2-naphthacenecarboxamide
[0274]
[0275] MS (FAB) m/z 549 ((M+H)+; | This invention provides compounds of the formula:
wherein A″, X and Y are defined in the specification. These compounds are useful as antibacterial agents. | 2 |
BACKGROUND
[0001] Data traffic congestion is a common problem in computer networks. Conventional congestion control methods include Transmission Control Protocol (TCP) congestion control, such as Random Early Detection (RED), Weighted RED (WRED), and Quantized Congestion Notification (QCN), which is standardized as Institute of Electrical and Electronics Engineers (IEEE) Standard 802.1 ua-2010. Both of these congestion control methods rely on rate adaption of the source based on feedback from the congestion point within the network. For RED congestion control, the feedback indicating congestion is typically provided by using packet discard. For QCN congestion control, the feedback indicating congestion includes explicit information about the rate of overload and the information is delivered to the flow source using a backward congestion notification message.
[0002] These and other conventional congestion control methods require relatively long times to settle a flow to a stable rate. With the delay bandwidth product of networks increasing more rapidly than the available switch buffer and with large transient traffic loads, these conventional congestion control methods do not provide adequate buffer control for high speed networks, such as datacenters.
BRIEF DESCRIPTION OF THE DRAWINGS
[0003] FIG. 1 is a block diagram illustrating one example of a network system.
[0004] FIG. 2 is a diagram illustrating one example of traffic flowing through a network system.
[0005] FIG. 3 is a block diagram illustrating one example of a server.
[0006] FIG. 4 is a block diagram illustrating one example of a switch.
[0007] FIG. 5 is a diagram illustrating one example of quantum flow control.
[0008] FIG. 6 is a diagram illustrating one example of an overload point.
[0009] FIG. 7 is a diagram illustrating one example of quantum flow control for a rate mismatch between a reaction point and an overload point.
[0010] FIG. 8 is a diagram illustrating one example of quantum flow control where flows from different reaction points merge.
[0011] FIG. 9 is a diagram illustrating one example of quantum flow control including forward flow control notification messages.
[0012] FIG. 10A is a list illustrating one example of the contents of a backward flow control notification message.
[0013] FIG. 10B is a list illustrating another example of the contents of a backward flow control notification message.
[0014] FIG. 11 is a list illustrating one example of the contents of a forward flow control notification message.
DETAILED DESCRIPTION
[0015] in the following detailed description, reference is made to the accompanying drawings which form a part hereof, and in which is shown by way of illustration specific examples in which the disclosure may be practiced. It is to be understood that other examples may be utilized and structural or logical changes may be made without departing from the scope of the present disclosure. The following detailed description, therefore, is not to be taken in a limiting sense, and the scope of the present disclosure is defined by the appended claims. It is to be understood that features of the various examples described herein may be combined with each other, unless specifically noted otherwise.
[0016] FIG. 1 is a block diagram illustrating one example of a network system 100 . Network system 100 includes a plurality of network devices. In particular, network system 100 includes a plurality of servers including servers 102 a - 102 d and a switching network 106 . Switching network 106 includes a plurality of interconnected switches including switches 108 a and 108 b. Switch 108 a is communicatively coupled to switch 108 b through communication link 110 . Each server 102 a - 102 d is communicatively coupled to switching network 106 through communication links 104 a - 104 d, respectively. Each server 102 a - 102 d may communicate with each of the other servers 102 a - 102 d through switching network 106 . In one example, network system 100 is a datacenter.
[0017] Network system 100 utilizes a congestion control method. In particular, network system 100 utilizes a quantum flow control method for low loss traffic management. The quantum flow control method is specifically adapted for low latency networks (e.g., datacenters) and uses quantized pause intervals applied at a fine grained flow level. The pause quantum, which is the time interval for draining a particular buffer within the network, is determined at the point of congestion and is reported to a selected flow source using a flow control notification message. The flow control notification message can be a backward flow control notification message or a forward flow control notification message. A buffer is determined to be overloaded based on a buffer utilization threshold while the pause quantum is determined based on estimates of the buffer drain rate. The flow source reacts to flow control notification messages by stopping all forward traffic for the specified time interval determined at the congestion point. The congestion point within the network continues to send flow control notification messages to selected flow sources as long as the buffer utilization threshold is exceeded.
[0018] FIG. 2 is a diagram illustrating one example of traffic flowing through a network system 120 . In one example, network system 120 is a layer 2 network. Network system 120 includes a first server 122 , a second server 128 , a third server 152 , a fourth server 156 , and a switching network 134 . Switching network 134 includes a first switch 136 and a second switch 142 . First server 122 is communicatively coupled to first switch 136 through communication link 126 . First switch 136 is communicatively coupled to second switch 142 through communication link 140 . Second server 128 is communicatively coupled to second switch 142 through communication link 132 . Second switch 142 is communicatively coupled to third server 152 through communication link 148 and to fourth server 156 through communication link 150 .
[0019] In this example, first server 122 is a reaction point (i.e., a source of frames) and includes a transmitter queue 124 . Second server 128 is also a reaction point and includes a transmitter queue 130 . First switch 136 includes a queue 138 , and second switch 142 includes a first queue 144 and a second queue 146 . Third server 152 is a destination for frames and includes a receiver queue 154 . Fourth server 156 is also a destination for frames and includes a receiver queue 158 . In one example, transmitter queues 124 and 130 , queues 138 , 144 , and 146 , and receiver queues 154 and 158 are First In First Out (FIFO) queues.
[0020] In this example, first server 122 is sending a unicast message to third server 152 . Frames in transmitter queue 124 are transmitted to first switch 136 , and the transmitted frames are received in queue 138 . The frames in queue 138 are forwarded by first switch 136 to second switch 142 , and the forwarded frames are received in first queue 144 . The frames in first queue 144 from first server 122 are then forwarded by second switch 142 to third server 152 , and the forwarded frames are received in receiver queue 154 . Second server 128 is sending a multicast message to third server 152 and fourth server 156 . Frames in transmitter queue 130 are transmitted to second switch 142 , and the transmitted frames are received in both first queue 144 and second queue 146 . The frames in second queue 146 are forwarded to fourth server 156 , and the forwarded frames are received in receiver queue 158 . The frames in first queue 144 from second server 128 are then forwarded by second switch 142 to third server 152 , and the forwarded frames are received in receiver queue 154 .
[0021] In this example, first queue 144 of second switch 142 is an overload point due to the merging of frames transmitted from first server 122 and second server 128 . In other examples, an overload point may occur due to frames from a single source or due to the merging of frames from three or more sources. To address this congestion at overload points within a network system, quantum flow control as disclosed herein is utilized.
[0022] FIG. 3 is a block diagram illustrating one example of a server 180 . In one example, server 180 provides each server 102 a - 102 d previously described and illustrated with reference to FIG. 1 and first server 122 , second server 128 , third server 152 , and fourth server 156 previously described and illustrated with reference to FIG. 2 . Server 180 includes a processor 182 and a memory 186 . Processor 182 is communicatively coupled to memory 186 through communication link 184 .
[0023] Processor 182 includes a Central Processing Unit (CPU) or other suitable processor. In one example, memory 186 stores instructions executed by processor 182 for operating server 180 . Memory 186 includes any suitable combination of volatile and/or non-volatile memory, such as combinations of Random Access Memory (RAM), Read-Only Memory (ROM), flash memory, and/or other suitable memory. Memory 186 stores instructions executed by processor 182 including instructions for a quantum flow control module 188 . In one example, processor 182 executes instructions of quantum flow control module 188 to implement the congestion control method disclosed herein. In other examples, quantum flow control is implemented by hardware state machines rather than by processor 182 .
[0024] FIG. 4 is a block diagram illustrating one example of a switch 190 . In one example, switch 190 provides each switch 108 a and 108 b previously described and illustrated with reference to FIG. 1 and first switch 136 and second switch 142 previously described and illustrated with reference to FIG. 2 . Switch 190 includes a processor 192 and a memory 196 . Processor 192 is communicatively coupled to memory 196 through communication link 194 .
[0025] Processor 192 includes a CPU or other suitable processor. In one example, memory 196 stores instructions executed by processor 192 for operating switch 190 . Memory 196 includes any suitable combination of volatile and/or non-volatile memory, such as combinations of RAM, ROM, flash memory, and/or other suitable memory. Memory 196 stores instructions executed by processor 192 including instructions for a quantum flow control module 198 . In one example, processor 192 executes instructions of quantum flow control module 198 to implement the congestion control method disclosed herein. In other examples, quantum flow control is implemented by hardware state machines rather than by processor 192 .
[0026] FIG. 5 is a diagram illustrating one example of quantum flow control 200 . Quantum flow control 200 involves source queues or FIFO's, such as FIFO 202 , network queues or FIFO's, such as FIFO's 204 , and destination queues or FIFO's, such as FIFO 206 . In this example, a source device, such as a server, transmits frames in a source FIFO 208 , and the transmitted frames are received in a network FIFO 212 of a forwarding device, such as a switch. The frames in network FIFO 212 are forwarded, and the forwarded frames are received in a network FIFO 218 of another forwarding device. The frames in network FIFO 218 are again forwarded, and the forwarded frames are received in a destination FIFO 222 of a destination device, such as a server.
[0027] Network FIFO 212 has a flow control threshold 214 . If a frame from source FIFO 208 exceeds the flow control threshold 214 of network FIFO 212 , a Backward Flow Control Notification (BFCN) message is generated as indicated at 216 . In one example, a backward flow control notification message is generated for each frame that exceeds the flow control threshold 214 of network. FIFO 212 . Network FIFO 218 has a flow control threshold 220 . If a forwarded frame from source FIFO 208 exceeds the flow control threshold 220 of network FIFO 218 , a backward flow control notification message is generated as indicated at 216 . A backward flow control notification message is generated for each frame that exceeds the flow control threshold 220 of network FIFO 218 . Likewise, destination FIFO 222 has a flow control threshold 224 . If a forwarded frame from source FIFO 208 exceeds the flow control threshold 224 of destination FIFO 222 , a backward flow control notification message is generated as indicated at 226 . A backward flow control notification message is generated for each frame that exceeds the flow control threshold 224 of destination. FIFO 222 .
[0028] Each backward flow control notification message 216 and 226 includes a pause duration, which is the time for draining the overloaded FIFO. For example, the pause duration included in a backward flow control notification message generated in response to the flow control threshold 214 of network. FIFO 212 being exceeded is a time interval long enough for draining network FIFO 212 . Likewise, the pause duration included in a backward flow control notification message generated in response to the flow control threshold 224 of destination FIFO 222 being exceeded is a time interval long enough for draining destination FIFO 222 . Each backward flow control notification message is transmitted to the source of the frame that caused the flow control threshold of the FIFO to be exceeded. In this example, each backward flow control notification message 216 and 226 is transmitted to the source device transmitting frames from source FIFO 208 .
[0029] In response to receiving a backward flow control notification message, the source stops transmitting for the pause duration. In this example, in response to each backward flow control notification message 216 and 226 , the source stops transmitting frames (as indicated for example by switch 210 ) from source FIFO 208 for the pause duration (as indicated by stopwatch 228 ). If transmission from a source FIFO is currently halted by a previous backward flow control notification message when another backward flow control notification message is received, the pause duration is reset to the maximum of the remaining pause duration and the new pause duration.
[0030] A quantum flow control reaction point (i.e., source FIFO 208 in this example) transmits at full speed until the reaction point receives a backward flow control notification message at which time the reaction point stops transmitting entirely for the pause duration (i.e., no slow start). Rate limiting at the quantum flow control reaction point is not directly affected by backward flow control notification messages. In one example, quantum flow control shapes the traffic flow to a provisioned max information rate. In another example, the max information rate is dynamically adjusted by taking measurements of the throughput over periods of time when the source FIFO is backing up and then adjusting the max information rate to match.
[0031] FIG. 6 is a diagram illustrating one example of an overload point 240 . In this example, three flows are merging into a FIFO 242 . The three flows are indicated by frames 246 a - 246 b from a first source, frames 248 a - 248 c from a second source, and frames 250 a - 250 b from a third source. FIFO 242 includes a free run buffer portion 243 and a guard buffer portion 344 . Free run buffer portion 243 is below a flow control threshold 345 , while guard buffer 344 is above flow control threshold 345 .
[0032] Below flow control threshold 345 , the frames pass without generating any backward flow control notification messages. In this example, frames 246 a , 248 a, 250 a, 250 b, and 248 b pass without generating any backward flow control notification messages. Above flow control threshold 345 , every new frame results in the generation of a backward flow control notification message. In another example, duplicate backward flow control notification messages are filtered at the overload point. In this example, frame 246 b results in the generation of backward flow control notification message 258 , and frame 248 c results in the generation of backward flow control notification message 262 .
[0033] Each backward flow control notification message 258 and 262 includes a pause duration as indicated by stopwatches 260 and 264 , respectively. The pause duration is determined based on three components. The first component is the Maximum Time To Drain (MTD) the overloaded FIFO as indicated at 252 . The second component is the Time To Source (TTS) from the overloaded FIFO as indicated at 254 . The third component is the Time From Source (IFS) to the overloaded FIFO as indicated at 256 . MTD can be calculated from the number of octets in the FIFO and the minimum guaranteed FIFO bandwidth. TTS is the latency for delivering a backward flow control notification message from the overloaded FIFO to the source FIFO. TFS is the latency for delivery of traffic from the source FIFO to the overloaded FIFO.
[0034] In one example, TTS and TFS are the sums of the hop and transmission delays. In a datacenter network, the transmission delay is insignificant relative to the hop delay. For unloaded FIFO's, the minimum hop delay equals one store-and-forward frame time plus switch pipeline delay (i.e., time from last bit in to last bit out). If, for example, the FIFO service rate is 10 Gbits and backward flow control notification messages are transmitted on an uncongested path and each backward flow control notification message is 672 bits on the wire, then the minimum hop delay for TTS=(672 bits*100 psec/bit)+500 nsec pipeline delay, for example)=567 nsec/hop. Therefore, for four hops, TTS=2268 nsec. If, for example, the FIFO service rate is 10 Gbits and data frames are transmitted on an uncongested path and the average data frame size is 1K octets (bimodal distribution of 2048 and 64 octets), the minimum hop delay for TFS=(8608 bits*100 psec/bit)+(500 nsec pipeline delay, for example)=1361 nsec/hop. Therefore, for four hops, TFS=5444 nsec. The 500 nsec pipeline delay is provided as an example. The actual pipeline delay may vary based on the implementation.
[0035] The guard buffer 344 is sufficient for quantum flow control at an overload point. With for example, a source rate to delivery miss-match of 4 Gbits/sec and TTS and TFS as approximated in the above example, one delay bandwidth product or a minimum of (TTS+TFS)*4 Gbits/sec=(2268 nsec+5444 nsec) 4 Gbits/sec=30,848 bits=3856 octets. Datacenter network switches, for example, may operate with about 256K octets/port divided between the FIFO's per port. The 256K octets/port is provided as an example and may vary based on the actual implementation. For 8 FIFO's per port, there are 32K octets per FIFO per port or about thirty 1056 octet frames. In one example, pooling the port buffers per FIFO allows sufficient reserve to provide the guard buffer. For 32 ports with 8 FIFO's each, for example, there is a total of 1 Mbyte/FIFO set. Setting the flow control threshold at 32 Kbytes will keep the operation at the buffer/port/FIFO limit.
[0036] FIG. 7 is a diagram illustrating one example of quantum flow control 300 for a rate mismatch between a reaction point 302 and an overload point 304 . Reaction point 302 transmits frames in a source FIFO 306 , and the transmitted frames are received in a network FIFO 308 . Reaction point 302 transmits the frames at a 10 Gbit rate. Network FIFO 308 has a flow control threshold 310 , which is not exceeded. The frames in network FIFO 308 are forwarded, and the forwarded frames are received in a network FIFO 312 . Network FIFO 312 includes a flow control threshold 314 , which is not exceeded. The frames in network FIFO 312 are forwarded, and the forwarded frames re received in a network FIFO 316 . The frames in network FIFO 316 are forwarded at a 1 Gbit rate. Network FIFO 316 includes a flow control threshold 318 , which is exceeded, thereby making network FIFO 316 an overload point. In this example, MTD for network FIFO 316 is indicated at 320 , TFS is indicated at 322 , and TTS is indicated at 324 .
[0037] At time t 0 , overload point 304 receives a frame f 0 that pushes network FIFO 316 past flow control threshold 318 , thereby generating a backward flow control notification message BFCN 0 330 including a pause duration PD 0 indicated at 326 to be sent to reaction point 302 . At time t 0 +TTS, reaction point 302 receives BFCN 0 330 and starts pausing transmission of frames (as indicated by stopwatch 334 ) for PD 0 326 . Past time t 0 +TTS, in response to each additional frame f 1 though f n , additional backward flow control notification messages BFCN 1 through BFCN n 332 arrive at reaction point 302 with pause durations PD 1 through PD n indicated at 328 , respectively. At time t n ≈t 0 +TTS+TFS, traffic from reaction point 302 will stop arriving at overload point 304 until time t n +(TTS+TFS+PD n ) given the source FIFO 306 is delivering constantly at its maximum capacity (e.g., a 10 Gbit rate) and all potential overload points are operating below their flow control thresholds except for the destination FIFO.
[0038] The pause delay seen at overload point 304 is sufficient to drain FIFO 316 . In one example, the drain time MTD=TTS+TFS+PD n . Therefore, PD n =MTD−(TTS+TFS), which is independent from the sourced bandwidth. If TTS+TFS is set to zero, there is no overrun risk of FIFO 316 , however, throughput is reduced.
[0039] FIG. 8 is a diagram illustrating one example of quantum flow control 340 where flows from different reaction points 342 merge. Reaction point 342 a for flow A transmits frames in a source FIFO 346 , and the transmitted frames are received in a network FIFO 350 . Network. FIFO 350 has a flow control threshold 352 , which is not exceeded. The frames in network FIFO 350 are forwarded, and the forwarded frames are received in a network FIFO 354 . Reaction point 342 b for flow B transmits frames in a source FIFO 348 , and the transmitted frames are received in network FIFO 354 . The frames from reaction point 342 a and from reaction point 342 b are merged in network FIFO 354 .
[0040] Network FIFO 354 has a flow control threshold 356 , which is not exceeded. The frames in network FIFO 354 are forwarded, and the forwarded frames are received in a network FIFO 358 . Network FIFO 358 includes a flow control threshold 366 , which is exceeded, thereby making network FIFO 358 an overload point. In this example, MTD for network FIFO 358 is indicated at 368 , the time from source for Flow A is indicated by TFS a 370 , the time from source for Flow B is indicated by TFS b 390 , the time to source for Flow A is indicated by TTS a 372 , and the time to source for Flow B is indicated by TTS b 384 .
[0041] At time t 0 , overload point 344 receives a frame f 0 from reaction point 342 a for Flow A that pushes FIFO 358 past flow control threshold 366 , thereby generating a backward flow control notification message BFCN 0 378 including a pause delay PD 0 indicated at 372 to be sent to reaction point 342 a, At time t m overload point 344 receives the last frame f m from reaction point 342 a for Flow A, thereby generating a backward flow control notification message BFCN m 380 for Flow A including a pause delay PD m indicated at 374 to be sent to reaction point 342 a. At time t n , overload point 344 receives the last frame f n from reaction point 342 b for Flow B, thereby generating a backward flow control notification message BFCN n 386 for Flow B including a pause delay PD n indicated at 376 to be sent to reaction point 342 b. At time t 0 +TTS a , reaction point 342 a receives BFCN 0 378 and starts pausing transmission of frames (as indicated by stopwatch 382 ) for PD 0 372 . At time t m +TTS a , reaction point 342 a receives BFCN m 380 and starts pausing transmission of frames (as indicated by stopwatch 382 ) for PD m 374 or continues pausing for the maximum of PD m or the remaining duration of a previous BFCN. At time t n +TTS b , reaction point 342 b receives BFCN n 386 and starts pausing transmission of frames (as indicated by stopwatch 388 ) for PD n 376 .
[0042] At time t m ≈t 0 +TTS a +TFS a , traffic from reaction point 342 a will stop arriving at overload point 344 until time t m +(TTS a +TFS a +PD m ). At time t n ≈t 0 +TTS b +TFS b , traffic from reaction point 342 b will stop arriving at overload point 344 until time t n +(TTS b +TFS b +PD n ). The pause delay seen at overload point 344 from reaction point 342 a is approximated by taking time MTD m =TTS+TFS a +PD m and solving for PD m giving PD m =MTD m −(TTS a +TFS a ). The pause delay seen at overload point 344 from reaction point 342 b is approximated by taking time MTD n =TTS b +TFS b +PD n and solving for PD n giving PD n =MTD n −(TTS b +TFS b ).
[0043] FIG. 9 is a diagram illustrating one example of quantum flow control 400 including forward flow control notification messages. Quantum flow control 400 involves a reaction point 402 , an overload point 404 , and a destination 406 . Reaction point 402 transmits frames in a source FIFO 408 , and the transmitted frames are received in a network FIFO 410 . Network FIFO 410 has a flow control threshold 412 , which is not exceeded. The frames in network FIFO 410 are forwarded, and the forwarded frames are received in a network FIFO 414 . Network FIFO 414 includes a flow control threshold 416 , which is exceeded, thereby making network FIFO 414 overload point 404 . The frames in network FIFO 414 are forwarded, and the forwarded frames are received in a destination FIFO 428 . Destination FIFO 428 has a flow control threshold 430 , which is not exceeded. In this example, TFS is indicated at 418 and TTS is indicated at 420 .
[0044] At time t 0 , overload point 404 receives a frame f 0 that pushes network FIFO 414 past flow control threshold 416 , thereby generating a forward flow control notification message FFCN 0 including a pause delay PD 0 indicated at 422 to be sent to reaction point 402 . In response to each additional frame f 1 though f n , additional forward flow control notification messages FFCN 1 through FFCN n 426 are generated and sent to reaction point 402 with pause delays PD 1 through PD n indicated at 424 , respectively. The forward flow control notification messages are received at the destination 406 . Destination 406 then converts each forward control notification message into a backward flow control notification message as indicated by BFCN 0 432 . At time t 0 +TTS, reaction point 402 receives BFCN 0 432 and starts pausing transmission of frames (as indicated by stopwatch 434 ) for PD 0 422 . At time t n ≈t 0 +TTS+TFS, traffic from reaction point 402 will stop arriving at overload point 404 until time t n +(TTS+TFS+PD n ).
[0045] FIG. 10A is a list 500 a illustrating one example of the contents of a BFCN message. In this example, the BFCN message includes a Layer 2 (L2) destination (i.e., reaction point address) 502 a, a Quantum Flow Control (QFC) BFCN frame identifier 504 a, and a pause duration in nanoseconds 506 a.
[0046] FIG. 10B is a list 500 b illustrating another example of the contents of a BFCN message. In this example, the BFCN message includes an Ethernet Header and Tags or other L2 information 502 b, a QFC frame identifier 504 b , and a pause duration in nanoseconds 506 b. Items 502 b, 504 b, and 506 b are similar to items 502 a, 504 a, and 506 a, respectively, as previously described and illustrated with reference to FIG. 10A . In addition, the BFCN message may include one or more of the following: a flow identifier 508 , a congestion point identifier 510 , an encapsulated priority 512 , an encapsulated destination Media Access Control (MAC) address 514 , an encapsulated MAC Service Data Unit (MSDU) length 516 , and an encapsulated MSDU 518 .
[0047] FIG. 11 is a list 520 illustrating one example of the contents of a Forward Flow Control Notification (FFCN) message. In this example, the FFCN message includes an L2 destination (i.e., original destination) 522 , a QFC FFCN frame identifier 524 , an L2 reaction point address 526 , and a pause duration in nanoseconds 528 .
[0048] Quantum flow control as described herein provides a very fast response and is therefore able to operate with small switch buffers common in single chip switch solutions. Quantum flow control responds effectively to transient overloads and short lived flows. Quantum flow control does not use per flow state in the switches and can manage congestion at a series of switch hops. Further, quantum flow control allows all flows to start at full rate, thereby reducing the effective transmission latency. In addition, quantum flow control can manage congestion of a multicast flow without any special consideration.
[0049] Although specific examples have been illustrated and described herein, it will be appreciated by those of ordinary skill in the art that a variety of alternate and/or equivalent implementations may be substituted for the specific examples shown and described without departing from the scope of the present disclosure. This application is intended to cover any adaptations or variations of the specific examples discussed herein. Therefore, it is intended that his disclosure be limited only by the claims and the equivalents thereof. | One example provides a network device including a queue to receive frames from a source, a processor, and a memory communicatively coupled to the processor. The memory stores instructions causing the processor, after execution of the instructions by the processor, to determine whether a flow control threshold of the queue has been exceeded, and in response to determining that the flow control threshold of the queue has been exceeded, generate a message to be sent to the source of the frame that exceeded the flow control threshold. The message includes a pause duration for which the source is to stop transmitting frames. | 7 |
FIELD OF THE INVENTION
[0001] The present invention relates image processing techniques, particularly, relates to a method and apparatus for generating 3D model of an object.
BACKGROUND OF THE INVENTION
[0002] In some situations, it is necessary to generate a non-contact three-dimensional (3D) model of an object, for example, the applications in 3D printer techniques. So far, one of the main methods of generating 3D model of an object is: multiple images of a target object are captured from different view angles by a specific imaging apparatus, and then these images from the different view angles are analyzed to generate a 3D model of the target object.
[0003] The present methods have some drawbacks, for example, 3D models require use of the specific imaging apparatus rather than regular ones. Consequently, it is difficult to build 3D models for objects because the specific imaging apparatus to build 3D models can only be used in certain environments.
SUMMARY OF THE INVENTION
[0004] Apparatus for generating 3D models of an object is provided herein, which can cooperate with typical imaging apparatus to implement the generation of 3D models so as to make gathering of 3D models simple.
[0005] According to one aspect of the present invention, the present invention provides a method for generating a three-dimensional model of an object, which comprises the steps: obtaining a plurality of two-dimensional image of the object at different object distance with an imaging apparatus, in which each image includes a plurality of pixels; assigning a third dimension coordinate (z) to each image, the third dimension coordinate (z) corresponding to the respective object distance; assigning two-dimensional coordinate (x, y) to each pixel; computing a sharpness valve for each pixel; for each two-dimensional coordinate (x, y), comparing the pixel sharpness value across all the images and selecting the image with the highest sharpness value; generating a plurality of three-dimensional coordinate (x, y, z) by combining each two-dimensional coordinate (x, y) with the third dimension coordinate (z) of the selected image; and generating the three-dimension model according to the plurality of three-dimensional coordinate (x, y, z).
[0006] The present invention also provides an apparatus for generating a three-dimensional model of an object. The apparatus includes: an imaging unit configured to obtain a plurality of two-dimensional images of the object at different object distances, in which the images includes a plurality of pixels; a computing unit configured to assign two-dimensional coordinate (x, y) to each pixel and a third dimension coordinate (z) to each image corresponding to the respective object distance, the computing unit further configured to compute a sharpness value for each pixel and compare the pixel sharpness values of each two-dimensional coordinate (x, y) across all the images to select the image with the highest sharpness value, the computing unit being also configured to generate a plurality of three-dimensional coordinate (x, y, z) by combining each two-dimensional coordinate (x, y) with the third dimension coordinate (z) of the selected image, and the computing unit further configured to the generate the three-dimensional model according to the plurality of three-dimensional coordinate (x, y, z); and a storage unit configured to store the image and the three-dimensional model.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] FIG. 1 is a flow chart illustrating a method for generating a 3D model of an object according an embodiment of the present invention.
[0008] FIG. 2 is a flow chart illustrating a method for generating a 3D model of an object according to an embodiment of the present invention.
[0009] FIG. 3 is a schematic diagram illustrating n th images to be gathered according to an embodiment of the present invention.
[0010] FIG. 4 is a schematic diagram illustrating a 3D model to be generated according to an embodiment of the present invention.
[0011] FIG. 5 is a diagram illustrating an apparatus for generating a 3D model of an object according to an embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0012] Advantages and features of the invention will become more apparent with reference to the following detailed description of presently preferred embodiments thereof in connection with the accompany drawings.
[0013] Referring to FIG. 1 , step 101 : images of an object are gathered by an imaging apparatus 10 shown in FIG. 5 , and “n” number of images of the object are gathered at different object distances during the gathering process. That is, the first image is gathered at the first object distance, and the second image is gathered at the second object distance, and the process is repeated “n” times (“n” being a natural number). The larger the number “n”, the more images are taken, and the more precise the final 3D model is. Object distances may be determined in various ways. For example, object distance may be a multiple of a unit of focus, and be increased or decreased in degrees of the unit of focus. That is, “n” number of images with “n” number of focuses are taken with the imaging apparatus. Alternatively, the object distance between the object and the imaging apparatus may be increased or decreased progressively by a preset unit distance to gather “n” number of images with the “n” number of object distances.
[0014] Step 102 : the sharpness of each pixel for each image is computed. The sharpness value is defined as the chromatic aberration between each pixel and other pixels surrounding thereof Each image taken by the imaging apparatus is a 2D image on a plane in a spatial coordinate system (x, y). The various image planes are parallel to each other along a depth spatial coordinate (z). Thus, each image plane may be defined as a X-Y plane and the corresponding plane depth coordinate is Z=1, 2, 3, . . . , n. See FIG. 3 for further clarifications. Consequently, n th image is on the plane that the equation is Z=n.
[0015] The position of each pixel for each image on the corresponding plane may be described with a two-dimensional coordinate (x, y). The sharpness value of each pixel for each image can be determined by the sharpness of one or more colors. For example, the sharpness of each pixel may be computed using an equation for tricolor sharpness:
[0000] Pixel( x, y, n )= aR *(Pixel R ( x, y, n ))+ aG *(Pixel G ( x, y, n ))+ aB *(Pixel B ( x, y, n )),
[0016] where Pixel(x, y, n) is the sharpness value of one current pixel at the position (x, y) for the n th image at Z axis; PixelR(x, y, n) is the red aberration between the current pixel and others surrounding thereof; PixelG(x, y, n) is the green aberration between the current pixel and others surrounding thereof; PixelB(x, y, n) is the blue aberration between the current pixel and others surrounding thereof; aR is a red weight parameter; aG is a green weight parameter; and aB is a blue weight parameter. It is noted that aR, aG, and aB can be dynamically modulated according to practical applications. Furthermore, PixelR(x, y, n) may be acquired with the equation as follow:
[0000] Pixel R ( x, y, n )= abs ( R ( x, y, n )− R (x−1, y, n ))+ abs ( R ( x, y, n )− R ( x, y− 1, n ))+ abs ( R ( x, y, n )− R ( x+ 1, y, n ))+ abs ( R ( x, y, n )− R ( x, y+ 1, n )),
[0017] where abs is absolute value sign; R(x, y, n) is the red value of current pixel at the position (x, y) for n th image at Z axis; R(x−1, y, n) is the red value of current pixel at the position (x−1, y) for n th image at Z axis; R(x, y−1, n) is the red value of current pixel at the position (x, y−1) for n th image at Z axis; R(x+1, y, n) is the red value of current pixel at the position (x+1, y) for n th image at Z axis; R(x, y+1, n) is the red value of current pixel at the position (x, y+1) for the n th image at Z axis. The same scheme may be used for the calculation of PixelG and PixelB and are not repeated here.
[0018] Step 103 : the plane on which an image is taken may be defined as the X-Y plane in space, and the depth location of each of the X-Y planes corresponds to a Z-axial value. The sharpness of points/pixels with the same 2D coordinate of all the planes are compared and the image plane with the most sharpness point is selected. The 2D coordinate (x, y) and the Z-axial value of the chosen planes are combined to get a 3D coordinate (x, y, z). In practice, a 2D coordinate (x 1 , y 1 ) can correspond to each Z-axial value Z=1, 2, . . . , n to get a plurality of points (x 1 , y 1 , 1), (x i , y i , 2) . . . , (x 1 , y 1 , n). The point at the plane Z=z 1 has the most sharpness so as to get a 3D coordinate (x 1 , y 1 , z 1 ). The aforementioned process is repeated to allocate each 2D coordinate (x, y) to a corresponding Z-axial value, which results in a plurality of 3D coordinates.
[0019] Step 104 : a 3D model is generated with 3D modeling tools according to these 3D coordinate.
[0020] According to an embodiment, the images of the object are gathered and in the gathering process, the object distance is modified to generate “n” number of 2D images. The sharpness of each pixel for each image is computed. Each of the 2D images taken corresponds to a plane and each plane corresponds to a 2D space X-Y axis and has a Z-axial (depth) value assigned according to its depth “n”. Taking an X-Y coordinate and finding the corresponding point/pixel on all the image planes, the sharpness of the point/pixel of the image is compared. From the comparison, the plane with the most sharpness point is selected and together with its Z-axial depth value, a 3D coordinate (x, y, z) is generated. This process is repeated for all the X-Y coordinate to get a plurality of 3D coordinate (x n , y n , z n ). Using this information, a 3D model is generated according to the 3D coordinate gathered. This method gathers images of the object by modifying the object distances, instead of needing to gather images by changing to different view angles. Since it is not necessary to gather images with different view angles, such method can be implemented with a regular imaging apparatus. Using the computed 3D coordinate of the object, a 3D model can be generated. Consequently, the method of the present invention makes gathering or generating a 3D model from an object simpler and broadens application fields.
[0021] Referring to FIG. 2 , an embodiment is described below which includes the steps:
[0022] Step 201 : the imaging apparatus is powered on and initial parameters are set. These initial parameters include: aperture is 2.8 and focus 0.7 m.
[0023] Step 202 : an image of a 3D object is taken by an imaging apparatus and gathered.
[0024] Step 203 : the focus setting of the imaging apparatus is modified and adjusted to increase by a unit.
[0025] Step 204 : Determine if the process is completed. If it is completed, go to step 205 . Otherwise, go back to step 202 and repeat the image gathering step. As shown in FIG. 3 , the gathered “n” number of images are distributed on Z-axis direction. The plane on which one of images is can be viewed as an X-Y plane, and each X-Y plane has a corresponding a Z-axis depth value.
[0026] Step 205 : the Pixel(x, y, n) sharpness of each pixel for each image is determined by the following equation:
[0000] Pixel( x, y, n )= aR *(Pixel R ( x, y, n ))+ aG *(Pixel G ( x, y, n ))+ aB *(Pixel B ( x, y, n )),
[0027] where Pixel(x, y, n) is the sharpness of the pixel at position (x, y) for the nth image on the Z axis; PixelR(x, y, n) is the red aberration between the pixel and others surrounding thereof; PixelG(x, y, n) is the green aberration between the pixel and others surrounding thereof; PixelB(x, y, n) is the blue aberration between the pixel and others surrounding thereof; aR is a red weight parameter; aG is a green weight parameter; and aB is a blue weight parameter.
[0000] Pixel R ( x, y, n )= abs ( R ( x, y, n )− R ( x− 1 , y, n ))+ abs ( R ( x, y, n )− R ( x, y −1 , n ))+ abs ( R ( x, y, n )− R ( x +1 , y, n ))+ abs ( R ( x, y, n )− R ( x, y +1 , n )),
[0028] where abs is absolute value sign; R(x, y, n) is the red value of one pixel at position (x, y) for n th image on the Z axis; R(x−1, y, n) is the red value of the pixel at position (x−1, y) for n th image on the Z axis; R(x, y−1, n) is the red value of one pixel at position (x, y−1) for n th image on the Z axis; R(x+1, y, n) is the red value of one pixel at position (x+1, y) for n th image on the Z axis; R(x, y+1, n) is the red value of one pixel at position (x, y+1) for n th image on the Z axis. The same calculation is used for PixelG and PixelB and is not further repeated here.
[0029] Alternatively, an ambiguity value of each pixel can be computed. That is, the more ambiguous the pixel image is, the less its sharpness value is. If ambiguity is calculated rather than sharpness, the pixel with the least ambiguity value is picked up to acquire its corresponding Z-axial value.
[0030] Step 206 : the sharpness of pixels/points that have the same 2D coordinate (x, y) for all images are determined. The pixel with the most sharpness is selected and has a corresponding Z-axial value, wherein the corresponding Z-axial value can be represented as Z(x, y)=Max(Pixel(x, y, 1), Pixel(x, y, 2) . . . , Pixel(x, y, n)). Then the 2D coordinate (x, y) and Z(x, y) are combined to obtain 3D coordinate (x, y, Z(x, y)). For example, referring to an embodiment shown in FIG. 4 , there are same X-axial and Y-axial values of points “A” and “B” on different X-Y planes. The Z-axial value of point “A” is represented as Z(x, y)=1, and the Z-axial value of point “B” is represented as Z(x, y)=5, and the same is obtained for all pixels.
[0031] Step 207 : a 3D model according to the plurality of 3D coordinates is generated.
[0032] Utilizing a set of different images taken with various change of focuses, sharpness values of multiple consecutive target images are analyzed to create a 3D projection model. The 3D projection model can be applied to facial modeling and other similar fields. If additional imaging apparatus is available for use, a whole 3D model of an object with more details can be generated by computing 3D projection models from different viewing angles. In practice, a high precision imaging apparatus may be equipped with a micrometer, and consecutive images are gathered along with shifting displacements of the micrometer. Thus, a high-precision 3D model is gathered or generated for the object. Alternatively, a microscopic imaging apparatus may be used for gathering a 3D model of a microscopic object.
[0033] Referring to FIG. 5 , according to an embodiment of the present invention, an equipment 1 for gathering 3D model includes an imaging apparatus 10 , a storage unit 11 and a computing unit 12 . The imaging apparatus 10 gathers “n” number of images of a target object by changing object distances, and outputs these images to the storage unit 11 to store the image information. The computing unit 12 computes the sharpness value of each pixel for each image. The sharpness is a chromatic aberration between a current pixel and surrounding pixels. That imaging plane may be defined as a transverse-coordinate plane, and a longitudinal coordinate is orthogonal to the transverse-coordinate plane. The sharpness of the pixels that have the same 2D coordinate (x, y) are compared across all the images to acquire a longitudinal axis value corresponding to the image having the pixel with the most sharpness. The transverse coordinates are combined with the longitudinal axis value to get 3D coordinate. A 3D model according to the 3D coordinate can be gathered.
[0034] The imaging apparatus may be a typical or regular equipment, for example, the imaging apparatus in practice may include an imaging optical apparatus, optical-sensitive apparatus (charge coupled device (CCD) or complementary metal-oxide-semiconductor (CMOS)), or other control module capable of controlling different objective distances for an imaging optical apparatus.
[0035] Preferably, the imaging apparatus 10 gathers the number “n” of images with increasing or decreasing in degrees of a unit of focus each time, and alternatively, the number “n” of images are gathered by increasing or decreasing various units of distance between the imaging apparatus and the target object.
[0036] Preferably, the computing unit 12 includes a sharpness computation sub-unit 120 . Each pixel on X-Y coordinate plane can be represented as a 2D coordinate (x, y). The sharpness of each pixel may be computed with the equation:
[0000] Pixel( x, y, n )= aR *(Pixel R ( x, y, n ))+ aG *(Pixel G ( x, y, n ))+ aB *(Pixel B ( x, y, n )),
[0000] where Pixel(x, y, n) is the sharpness of one current pixel at position (x, y) for the nth image at Z axis; PixelR(x, y, n) is the red aberration between the current pixel and others surrounding thereof; PixelG(x, y, n) is the green aberration between the current pixel and others surrounding thereof; PixelB(x, y, n) is the blue aberration between the current pixel and others surrounding thereof; aR is a red weight parameter; aG is a green weight parameter; and aB is a blue weight parameter.
[0037] Preferably, the sharpness computation sub-unit 120 acquires PixelR(x, y, n) by utilizing the equation as follow:
[0000] Pixel R ( x, y, n )= abs ( R ( x, y, n )− R ( x −1 , y, n ))+ abs ( R ( x, y, n )− R ( x, y −1 , n ))+ abs ( R ( x, y, n )− R ( x+ 1 , y, n ))+ abs ( R ( x, y, n )− R ( x, y +1 , n )),
[0038] where abs is absolute value sign; R(x, y, n) is the red value of one current pixel at position (x, y) for the n th image at Z axis; R(x−1, y, n) is the red value of the current pixel at position (x−1, y) for the nth image at Z axis; R(x, y−1, n) is the red value of the current pixel at position (x, y−1) for the nth image at Z axis; R(x+1, y, n) is the red value of the current pixel at position (x+1, y) for the nth image at Z axis; R(x, y+1, n) is the red value of the current pixel at position (x, y+1) for the n th image at Z axis.
[0039] Preferably, the computing unit 12 further includes a gathering unit 122 of 3D coordinate. Each pixel on X-Y coordinate plane can be represented as a 2D coordinate (x, y) and corresponds to a Z-axial value to represent as Z(x, y). The sharpness of pixels that have same 2D coordinate (x, y) for all images are determined. The pixel with the most sharpness is selected to work out its corresponding Z-axial value, wherein the corresponding Z-axial value can be represented as Z(x, y)=Max(Pixel(x, y, 1), Pixel(x, y, 2) . . . Pixel(x, y, n)). Then the 2D coordinate (x, y) and Z-axial value Z(x, y) are combined to get 3D coordinate (x, y, Z(x, y)). Using the 3D coordinate, the apparatus generates a 3D model of the target object.
[0040] While the invention has been described in terms of what is presently considered to be the most practical and preferred embodiments, it is to be understood that the invention needs not be limited to the disclosed embodiments. It is intended to cover various modifications and similar arrangements included within the spirit and scope of the appended claims which are to be accorded with the broadest interpretation so as to encompass all such modifications and similar structures. | A method of generating a 3D model from an object comprises: gathering a plurality of images of an object, and the object distance is modified to generate different images; computing the sharpness of each pixel of each image; defining each of the images being on a plane, and each of the planes corresponds to a 2D space which also corresponds to a Z-axial value; comparing the sharpness of points with the same 2D coordinate of all the planes, and picking up the plane with the most sharpness point, and then combining the 2D coordinate and the Z-axial value of the picked plane, to get a 3D coordinate; repeating the last process to get a plurality of 3D coordinate; gathering a 3D model according to the 3D coordinate. This invention is able to be achieved with the prior imaging device and the whole process of gathering a 3D model is simplified. | 6 |
TECHNICAL FIELD
This invention relates generally to semiconductor devices and particularly to a method of fabricating such devices in which a non-silicon semiconductor is grown over a silicon substrate with the lattice constant mismatch between the non-silicon semiconductor and the silicon substrate being accommodated by an intermediate region which utilizes tin as a major component.
BACKGROUND OF THE INVENTION
Silicon is the semiconductor most commonly used for integrated circuits, and silicon integrated circuit technology is presently extremely well developed. The dominant position of silicon in the integrated circuit markets is partially due to the fact that it is both abundant and relatively inexpensive as compared to other semiconductors such as Group III-V compound semiconductors. For example, silicon wafers or substrates are presently approximately in order of magnitude cheaper than are GaAs wafers. The integrated circuit or other device is often fabricated using an epitaxial layer of silicon which is grown on the silicon substrate although the circuit may be fabricated directly on the wafer.
However, for a variety of reasons, it is often desirable to have epitaxial semiconductors other than silicon on silicon substrates. In pursuing this direction, the objective is to enhance the range of useful devices which can be fabricated using silicon substrates. For example, some semiconductors, such as Group III-V compound semiconductors, may lead to devices in which the carrier mobility is higher than it is in silicon devices or they may make it possible to integrate optical functions with electronic functions on the same substrate. In the latter case, it is contemplated that Group IV, III-V, II-VI or other compound, as well as non-silicon elemental, semiconductors will be used to fabricate optical devices while the electronic functions will be performed either by devices fabricated in silicon or in the epitaxial layers of the non-silicon semiconductor. Compound semiconductors are preferred over silicon for the optical functions because they often have a direct bandgap, while silicon has an indirect bandgap, and have bandgaps which extend over a wide range of wavelengths. The latter feature permits fabrication of optical devices, e.g., lasers and photodetectors, which are useful over a broad range of wavelengths including the visible and the infrared. This approach to device fabrication thus combines the low cost, easy handling, ready avalability, etc., of silicon substrates as well as the mature Si very large scale integration technology with the desirable attributes offered by other semiconductors.
However, growth of high quality non-silicon semiconductors on silicon substrates is generally extremely difficult because the desired non-silicon semiconductors typically have lattice constants that differ significantly from that of silicon, and high quality epitaxial growth is thus difficult to obtain because of the lattice constant mismatch. When utilization of the heterointerface is not required, various intermediate layers may be grown provided that the top layers where the devies will be located are of the desired device quality. Although there are many pitfalls in the path of this development, some, e.g., such as the possible chemical incompatibility of the two materials or their different lattice symmetry, are not directly related to the lattice mismatch. The latter, which is the concern of this application, manifests itself adversely by generating misfit dislocations, which thread the epitaxial layers, thus degrading their quality.
One approach to increasing the number of semiconductors which may be grown with a high degree of crystalline perfection on a particular type of substrate is to use a strained layer superlattice between the substrate and the desired semiconductor. A strained layer superlattice consists of a plurality of interleaved layers having different compositions and lattice constants with the strain produced by the lattice constant mismatch between the two semiconductors being accommodated by distortion of the lattice rather than by generation of misfit dislocations. For example, a plurality of GaAs layers may be interleaved with a plurality of AlGaAs layers.
Strained layer superlattices may also be used in a different context which has been used successfully with, for example, GeSi superlattices grown on, for example, Si substrates. A compositionally graded layer may be grown between the substrate and the superlattice. The lattice constant of the compositionally graded layer varies from that of the substrate to that of the desired compound semiconductor. The misfit dislocations that arise because of the lattice mismatch between the compositionally graded layer and the substrate often have their propagation terminated in the superlattice. Although the reason for this behavior is not presently known with absolute certainty, it is likely to be associated with the additional strain introduced by the superlattice which makes the threading propagation of a dislocation unfavorable. Thus, the misfit dislocations generated by the compositionally graded layer are trapped in the superlattice, and homogeneous alloy layers grown above the superlattice may now be used as a substrate for the epitaxial growth of additional semiconductor layers which are lattice matched to those alloy layers rather than the substrate.
Although many combinations of semiconductors have been proposed for the strained layer superlattices, one combination of semiconductors that has not received any attention from those skilled in the art is the combination of tin and another Group IV semiconductor. The use of tin appears especially attractive because it has a lattice constant of 0.6489 nm as opposed to 0.5431 or 0.5646 nm for silicon or germanium, respectively. Such a large lattice constant difference opens the possibility of epitaxially growing many types of compound semiconductors on a SiSn or GeSn alloy layer grown on a silicon or germanium substrate after a superlattice has been used to trap the misfit dislocations. However, those skilled in the art have studiously avoided the use of such tin containing superlattices. It was believed that solid alloys of tin with Ge or Si could not be grown successfully because solid solutions of tin with the other Group IV elements exhibit segregation when cooled from the melt.
SUMMARY OF THE INVENTION
A region comprising tin and at least one other Group IV semiconductor permits the epitaxial growth of semiconductors, and thus the fabrication of devices in these semiconductor materials, within a wide range of lattice constants over either Si or Ge substrates. The device comprises: in sequence, a substrate comprising at least one semiconductor selected from the group consisting of Si and Ge; a region comprising tin and at least one other Group IV semiconductor; and a region comprising at least one non-silicon semiconductor in which desired devices are fabricated. The latter region is approximately lattice matched to the top of the tin containing region. The tin comprising region comprises a compositionally graded region in which the percentage of tin increases, i.e., a region of Sn x Si 1-x with x increasing from 0.0 to a value of x o , such that the lattice constant of the Sn x .sbsb.o Si 1-x alloy matches that of the desired epitaxial semiconductor, and a superlattice comprising interleaved layers of Sn x Group IV 1-x and Sn y Group IV 1-y compound semiconductors with the values of x and y selected so that the average lattice constant of the superlattice is close to the lattice constant of the non-silicon semiconductor. The superlattice region traps the misfit dislocations generated in the growth of the compositionally graded region. Other substrate compositions may be used.
The tin comprising region is preferably grown by molecular beam epitaxy which is a low temperature growth process. Because of this, it is a nonequilibrium process in which segregation of tin from the other Group IV element does not occur resulting in a metastable heterostructure. The resulting alloy is metastable.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a schematic view of a semiconductor device according to this invention;
FIG. 2 plots the mole fraction of tin vertically versus the distance from the substrate horizontally for a typical varying composition region according to this invention;
FIG. 3 plots the lattice constant in units of angstroms vertically versus the percentage of tin horizontally for Sn x Si 1-x alloys; and
FIG. 4 plots the energy vertically in units of eV versus the composition horizontally for Sn x Ge 1-x alloys.
DETAILED DESCRIPTION
An exemplary embodiment of a device according to this invention is depicted in FIG. 1. The device comprises substrate 1; tin containing region 3 and non-silicon semiconductor region 5. The tin containing region comprises a region 7 having a graded composition, a superlattice region 9, and a buffer region 11. The superlattice comprises a plurality of layers as shown by the dotted lines. For reasons of clarity, only several layers are shown although it is to be understood that many more will usually be present in the actual structure. The substrate comprises, in a preferred embodiment, at least one semiconductor selected from the group consisting of Si and Ge. Other compositions may be used. Si substrates are presently preferred because of their high quality and easy availability. The tin (Sn) containing region comprises Sn and at least one other Group IV semiconductor. That is, it comprises Sn and at least one semiconductor selected from the group consisting of Group IV semiconductors including Si, Ge and C. Non-silicon semiconductor region 5 is approximately lattice matched to the buffer region 11 on the superlattice. The choice of semiconductor for region 5 will be discussed later. Of course, region 5 may comprise more than one semiconductor. For example, a plurality of epitaxial layers lattice matched to each other but having different compositions may be grown.
The structure of the tin comprising region will be better understood by reference to FIG. 2 which plots the mole fraction of tin vertically in the Sn x Si 1-x alloy versus the distance horizontally, in arbitrary units, from the substrate for the tin comprising region for one embodiment, namely, Sn 0 .5 Si 0 .5. This embodiment is selected solely for purposes of illustration. As will be readily appreciated by those skilled in the art, other alloy compositions may be used depending upon the desired lattice constant. The region depicted is grown on a Si substrate. A Si buffer layer is present from Z 0 to Z 1 , and a compositionally graded layer is present from Z 1 to Z 2 . The composition at Z 2 has the lattice constant desired for the non-silicon semiconductor region 5. The superlattice region extends from Z 3 to Z 4 . A SnSi buffer layer is grown before the superlattice. Of course, the layers in the superlattice must be sufficiently thin so that misfit dislocations do not become energetically favorable, i.e., the lattice mismatch is accommodated by strain rather than by the generation of misfit dislocations. During growth of the graded composition region, that is, the region extending from Z 1 to Z 2 , misfit dislocations are generated. However, during the growth of the superlattice, that is, the structure extending from Z 3 to Z 4 , the misfit dislocations are trapped with the strained layer region. Consequently, the region from Z 4 upwards is free of dislocations. In the example depicted, the metastable alloy has a lattice constant of approximately 0.596 nm. For other lattice constants, the mole fraction of tin in the superlattice will be selected to give the desired lattice constant.
In a preferred embodiment, the superlattice region comprises interleaved layers of Sn 1-x Si x in which x is larger in the first plurality of interleaved layers than it is in the second plurality of interleaved layers. The choice of the two values of x within the superlattice region is dictated by the requirement that the superlattice region trap the misfit dislocations generated during the growth of the graded composition region. More generally, the superlattice region comprises Sn x Group IV 1-x where Group IV is at least one Group IV elemental semiconductor.
The ultimate value of Sn in the graded composition region is determined by the lattice constant of the compound semiconductor region grown on the superlattice. That is, the two lattice constants should be approximately equal. FIG. 3 plots the lattice constant vertically in Angstroms versus the tin fraction horizontally in units of x for selected semiconductors. Ten Angstroms equals 1 nm. Semiconductors whose lattice constants are depicted include Ge, GaAs, InP, and Sn 0 .27 Ge 0 .73. The positions of other semiconductors on this graph will be readily known to those skilled in the art and therefore need not be shown. Growth of Group II-VI, III-V, as well as mixed group semiconductors is contemplated.
As Sn x Si 1-x alloys exhibit phase segregation when cooled from a bulk solution, it is necessary that the Sn containing regions be grown by a non-equilibrium process. A non-equilibrium process is defined as any process which lacks sufficient kinetic energy for phase segregation to occur growth. The alloy layer will then be metastable, i.e., its constituents lack the energy required to overcome the kinetic barrier and reach the minimum energy, phase-segregated state. A low temperature epitaxial growth, such as molecular beam epitaxy, is presently preferred. Growth at temperatures less than approximately 500° C. is desirable. However, it is possible that other growth techniques, such as chemical vapor deposition or metalloorganic chemical vapor deposition, may also proceed at a temperature sufficiently low that phase segregation does not arise. The upper limit on x within the superlattice region is determined by the thermal stability in the epitaxial layer at the growth temperatures, and also, possibly, by the requirement of having a sufficient glitch amplitude over the average alloy composition. It appears unlikely that the technique will be useful for values of x greater than approximately 0.6.
Although growth of Sn x Si 1-x alloys in region 5 on Si substrates is the preferred way of practicing this invention, other embodiments are contemplated. For example, region 5 may comprise a Sn x Ge 1-x alloy with either a Si or Ge substrate. This alloy, especially with x greater than approximately 0.27, is of particular interest because it is believed to be a direct bandgap semiconductor. If desired, this alloy may be grown directly on an InP substrate to which it is approximately lattice matched. FIG. 4 plots the energy of the bandgap vertically in units of eV versus the composition horizontally in units of x. The regions of the indirect and direct bandgaps are shown as well as the regions in which the alloy becomes a semi-metal. It is noted that Sn x Ge 1-x also does not exist in the equilibrium bulk form because of phase segregation. For values of x greater than approximately 0.25, the alloy will have a conduction band minimum in k=0 valley and therefore one can expect a high electron mobility as well as low effective mass. It is also noted that this direct bandgap material offers the possibility fabricating long wavelength, that is, greater than 2.5 um, optical devices including photodetectors and light sources such as light emitting diodes and lasers. The SnGe layer may be used as a substrate for the growth of further layers or devices may be fabricated directly in the SnGe layer.
The devices contemplated for the compound semiconductor region are numerous and include integrated circuits, oscillators, photodetectors, lasers, etc. | A semiconductor device comprising an epitaxially grown tin and Group IV compound semiconductor region on which at least one other semiconductor is grown lattice matched to the adjacent portion of the tin containing region. A large number of semiconductors may thus be grown. | 7 |
BACKGROUND OF THE INVENTION
1. FIELD OF THE INVENTION
The present invention relates to a disk storage unit such as a hard-disk drive or an optical-disk drive and, more particularly, to a positioning control of the head of the disk storage unit.
2. DESCRIPTION OF THE RELATED ART
The control circuit of a conventional disk storage unit is shown in FIG. 6. When the head of the disk storage unit is moved from a certain track to a target track and data is written or read, the following two sequential controls are needed: (1) Terminals a and c of a switch 1 are connected, and a head actuator 5 is driven by a drive signal 4. The head of the disk storage unit is moved by the head actuator 5, and the head position is detected by a head position sensor 8. The head position sensor 8 gives a difference of location between the track and the head and also generates a tracking error signal 2 having a periodicity every one track. The periodicity of this tracking error signal 2 is counted by a counter 6, the distance between the target track and the head is calculated, and a signal 3 corresponding to that distance is transmitted to a velocity command generator 14. The velocity command generator 14 outputs a velocity command, based on the distance between the target and the head. A velocity detector 12 detects the velocity of the head from the frequency of the tracking error signal 2. The current head velocity and the output of the velocity command generator 14 are compared in a comparator 9. The comparator 9 generates the drive signal 4 for correcting the difference between the current head velocity and the generator output. This is repeated until the head reaches the target track. The control described above is referred to as seek control, and the operation is referred to as a seek operation. (2) Once the head reaches the target track, terminals b and c of the switch 1 are connected and the head is controlled so that it is within one track and tracks the central location of the target track at all times. This control is referred to as tracking control, and this operation is referred to as a tracking operation.
The seek operation preferably ends in the shortest possible time, so the maximum acceleration and deceleration of the actuator are used. In general, the maximum acceleration is used as far as the intermediate point between the current head position and the target track, and the maximum deceleration is used from the intermediate point to the target track. With this control, the head velocity is sufficiently decelerated by the time the head reaches the target track, and the head is pulled over the target track in tracking control. However, if the head velocity is not decelerated sufficiently when the head reaches the target track, the head will converge on other than the target track, or the head will not converge at all and the actuator will be moved up to its movable limit. Therefore, the head velocity as the seek operation is switched to the tracking operation is very important. FIG. 7 shows how the head converges on the target track at different velocities. The axis of ordinates is track location and the axis of abscissas is time. Solid line a in FIG. 7 shows that the head velocity indicated by the solid line a' is sufficiently small and converges on the correct track, while broken line b of FIG. 7 shows that the head velocity indicated by broken line b' is too large and converges on another track 2, not a target track. FIG. 8 shows the relationship between the tracking error signal and time in the same case as FIG. 7.
The allowable range of the head velocity as the seek operation is switched to the tracking operation is determined by the pulling ability of tracking control, and seek control must be performed at a rapid acceleration and deceleration to shorten seek time. Therefore, the head velocity at a target track is difficult to maintain in the allowable range. To reliably put the head velocity in the allowable range, the inclination of the velocity curve of the head is made slower as the head approaches the target track. That is, the head velocity is reduced as the head approaches the target track. The variations in the head velocity are shown in FIG. 9.
In addition, even if dc offsets, gain fluctuations, and distortions caused by disk shape asymmetry are contained in the tracking error signal and fluctuations are contained in the actuator gain, pulling of the head to the target track becomes easier if the head velocity is reduced sufficiently.
In most optical disks, a push-pull method using a split-half detector is used to detect the tracking error signal. In this method, a dc offset occurs easily in the tracking error signal because of the optic-axial offset of an objective lens, and pulling of the head in tracking control tends to fail even at the offset of the tracking error signal.
As described above, in the method in which the inclination of the velocity curve of the head is made slower as the head approaches the target track, it is difficult for the optic-axial offset of the objective lens to occur because oscillation exerted on the lens is reduced, but the seek time becomes late.
In addition, PUPA No. 4-38724 discloses a method wherein the offset of a tracking error signal is detected in the latter half of a seek operation, an offset is added to the tracking error signal, and, after the seek operation, the tracking operation is made stable. However, in the method disclosed in this publication, the inclination of the deceleration curve of the head is made slower as shown in FIG. 9, so seek time is not shortened. In addition, since an offset that is added is in the seek operation, what is added is only for making the offset of the tracking error signal zero.
Further, PUPA No. 62-162240 discloses that the amount of offset occurring immediately after a pulling operation is detected and that offset is made zero by adding an offset to the tracking error signal. However, the allowable range of the head velocity cannot be changed by only making the offset zero.
SUMMARY OF THE INVENTION
Accordingly, an object of the present invention is to stably shorten seek time.
In addition, another object of the present invention is to expand the allowable range of head velocity at which the head can be pulled to a target track.
Still another object of the present invention is to prevent a failure of pulling, which is caused by optic-axial offset of objective lenses in optical disks and by unevennesses of disk groove shapes and gain fluctuations in actuators and sensors in disk storage units.
A further object of the present invention is to provide tracking control capable of stably pulling the head to a target track even if the head reaches the target track at high velocity.
A disk storage unit according to the present invention has a disk for storing data, a head for at least reading data stored on said disk, a controller for performing a seek operation and a tracking operation based on a tracking error signal after the head reaches said target track once. The seek operation is for controlling the head to move to a target track from a current track, and the tracking operation is for controlling the head to follow the target track. The invention further includes a device for accumulating a dc offset onto the tracking error signal after switching from the seek operation to the tracking operation to generate a power for driving the head. The power corresponds to the head speed in the seek operation and is opposed to the direction of the seek operation. With this structure, the allowable range of head velocity when the seek operation is switched to the tracking operation can be expanded.
The above disk storage unit may further include a device for accumulating a second dc offset onto the tracking error signal so that the offset of the tracking error signal itself is removed. With this structure, pulling is stable.
The amount of dc offset and second dc offset may be attenuated as time elapses. With this structure, control can be switched stably.
Also, the velocity of the head in the seek operation on which head drive power is based may be a velocity immediately before the seek operation is switched to the tracking operation.
Further, in some cases, it is preferable that the amount of dc offset added to the tracking error signal be proportional to the velocity of the head.
In accordance with another aspect of the present invention, there is provided a disk storage unit, which has a disk for storing data, a head for at least reading data stored on the disk, and a head drive for performing a seek operation and a tracking operation based on a tracking error signal after the head reaches a target track once. The seek operation is for controlling the head to move to a target track from a current track, and the tracking operation is for controlling the head to follow said target track. This invention also includes a device for generating the drive signal that is nonlinear to a distance between the position of the head and the location of the target so that attenuation of the velocity of the head becomes large after switching from the seek operation to the tracking operation. With this structure, the allowable range of the head velocity when the seek operation is switched to the tracking operation can also be expanded.
In accordance with still another aspect of the present invention, there is provided a head controller which controls a seek operation and a tracking operation in a disk storage unit. This invention has a position sensor for generating a tracking error signal representative of a positional offset between the head and the target track, a detection device for detecting a velocity and a direction of movement of the head in the seek operation, and a generation device connected to the detection device for generating a dc offset corresponding to the detected velocity and the detected direction of movements, a device for accumulating the dc offset generated by the generation device onto the tracking error signal.
Also, the head controller may further have a second detection device for detecting an offset of the tracking error signal itself in the seek operation, a second generation device connected to the second detection device for generating a second dc offset so that the offset of the tracking error signal itself becomes zero, and a device for accumulating the second dc offset generated by the second generation device onto the tracking error signal.
Further, the dc offset and the second dc offset may be attenuated as time elapses and added to the tracking error signal.
The dc offset proportional to the velocity of the head in the seek operation may be added to the tracking error signal.
The foregoing and other objects, features and advantages of the invention will be apparent from the following more particular description of a preferred embodiments of the invention, as illustrated in the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a block diagram showing the essential structure of the present invention, the essential structure being inserted into the block 10 in FIG. 2.
FIG. 2 is a block diagram showing the overall structure of the present invention.
FIG. 3 is a graph showing a range in which pulling of a head succeeds by variations in the relationship between the head velocity and an offset.
FIG. 4 is a graph showing how the head converges on a target track at different velocities in accordance with the present invention.
FIG. 5 is a graph showing the relationship between the tracking error signal and the head velocity of the disk storage unit according to the present invention.
FIG. 6 is a block diagram showing the control circuit of a conventional disk storage disk.
FIG. 7 is a graph showing how the head of the conventional disk storage unit converges on a target track at different velocities.
FIG. 8 is a graph showing the relationship between the tracking error signal and the head velocity of the conventional disk storage unit.
FIG. 9 is a graph showing how the head velocity of the conventional disk storage unit varies with time.
An object of the present invention is to stably shorten seek time and to expand the allowable range of head velocity at which the head can be pulled to a target track.
DESCRIPTION OF THE PREFERRED EMBODIMENT
FIG. 1 is a block diagram showing the essential structure of the present invention. This essential structure is inserted into a block 10 of FIG. 2. The block 10 for converting a signal 2 of FIG. 6 is added to FIG. 2. In FIG. 1, a tracking error signal 2 is input to an operational amplifier (adder-subtracter) 41, a low-pass filter (LPF) 21, and a velocity detector 29. The output of the LPF 21 is input to an operational amplifier (adder-subtracter) 37 through a switch 23A. Also, the output of the velocity detector 29 and the output from the head-movement-direction detection means 43 are input to the dc offset generation means 31, which generates a dc offset. The dc offset generated by the dc offset generation means 31 is input to an operational amplifier (adder-subtracter) 39 through a switch 23B. The outputs of the operational amplifiers 37 and 39 are input to the negative input terminal of the operational amplifier 41, and the output of the operational amplifier 41 is input to a phase compensator 7 of FIG. 2.
The operation is hereinafter described. FIG. 1 corresponds to the block 10 in FIG. 2 and operations other than the block 10 are the same as those in FIG. 6, so the influence of the output is not transmitted to the head actuator 5 during a seek operation. However, since a tracking error signal 2 is output at all times, it is also input to the LPF 21 and the velocity detector 29 at all times. The LPF 21 detects the average dc level of the tracking error signal 2 in the seek operation. The switches 23A and 23B are closed during the seek operation, and the average level is held in a capacitor 25. This is for correcting the offset of the tracking error signal itself, which is caused by optic-axial offset of objective lenses in optical disks and by nonuniformity in disk groove shapes and gain fluctuations in actuators and sensors in disk storage units.
Furthermore, the velocity detector 29 detects a velocity from the frequency of the tracking error signal 2, as in the case of a velocity detector 12 of FIG. 2, and inputs the detected velocity to the dc offset generation means 31. This velocity detector 29 can be omitted and the output of the velocity detector 12 can be connected. The dc offset generation means 31 reads the velocity and outputs a predetermined dc offset corresponding to that velocity. Since this dc offset preferably corresponds to the velocity of the head of the disk storage unit at the time that the head has reached a target track, a dc offset corresponding to the head velocity immediately before the seek operation is switched to the tracking operation (most preferably, a velocity for an interval of one track before the switching) is output, and the capacitor 33 is charged through the closed switch 23B. This dc offset must have a polarity corresponding to the direction of head movement in the seek operation. This is because an offset that reduces the velocity of the head differs depending on the direction of movement. Therefore, a means for detecting the direction in which the head moves (head-movement-direction detection means 43) is needed. In the embodiment of the present invention, it is preferable that a dc offset proportional to the head velocity be added. The present invention, however, is not limited to this condition.
If the head of the disk drive has reached the target track, the mode is switched from the seek operation to the tracking operation. The switches 23A and 23B are open, so a current flows through a resistor 27 via the capacitor 25 and a current flows through a resistor 35 via the capacitor 33. The offsets held in the capacitors 25 and 33 are then input to the operational amplifier 41 through operational amplifiers 37 and 39. Since the tracking error signal 2 is also input to the operational amplifier 41, the tracking signal 2 from which the dc offset from the operational amplifier 37 and the dc offset from the operational amplifier 39 are subtracted is output from the operational amplifier 41. That is, a signal, which is equal to (tracking signal--dc offset from the operational amplifier--dc offset from the operational amplifier), is output from the operational amplifier 41. The output of the operational amplifier 37 is a dc offset of the tracking error signal itself, and the output of the operational amplifier 39 is a dc offset that enhances the pulling ability on the target track.
The output from the block 10 is transmitted to the phase compensator 7 and to the head actuator 5 through terminals b and c of the switch 1.
Electrical charges held in the aforementioned capacitors 25 and 33 are reduced as time elapses and become zero after a certain time. With this, two types of offsets no longer influence the tracking error signal 2 after a certain time, and a normal tracking operation is to be performed. This certain time relates to the time constant, i.e., capacity of a capacitor, so it is necessary to select a capacitor, with an appropriate capacity.
While, in the aforementioned embodiment, the tracking error signal has been corrected by adding an offset to the tracking error signal, it is noted that the velocity of the head can also be largely reduced by a circuit which outputs a drive signal, which is nonlinear to the amplitude of the tracking error signal, to the head actuator, after the head has reached the target track and the seek operation has been switched to the tracking operation.
The aforementioned embodiment is not limited to the circuit shown in FIG. 1. For example, the operational amplifier 41 can be replaced by any type of circuit that can add signals. Capacitors 25 and 33 can also be replaced by a power source and the like controlled to be attenuated with the elapse of time. It is also possible to replace the circuits of FIG. 2 excluding the section corresponding to FIG. 1 with circuits having the same functions.
In addition, for the velocity detector, head-movement-direction detection means, means for switching modes, and the like, they may be circuits controlled by microcomputers or circuits by which signals are generated.
FIG. 3 shows the relationship between the amount of offset and pulling velocity. The axis of abscissas represents head velocity immediately before the seek operation is switched to the tracking operation, and the axis of ordinates represents the amount of offset that is added to a tracking error signal. Below and to the left of line a is where pulling to the target track succeeds. The part between lines a and b is where the head converges at a location one track away from the target track. The part between lines b and c is where the head converges at a location two tracks away from the target track. In control without adding an offset as in the conventional disk storage unit, the head cannot be pulled unless the head velocity is less than about 4 kHz (4000 track/s). However, the head can be pulled at a velocity up to about 7 kHz (7000 track/s) by adding an appropriate offset. That is, the offset functions as a bias drive force to the actuator 5 and, in tracking control, the offset reduces the head velocity, which could not be reduced sufficiently in seek control. However, it is necessary to add an offset larger than the amplitude of the tracking error signal because the larger offset may cause the head to converge on another track.
In addition, if the offset quantity is proportional to the velocity of the head and the offset is made smaller when the head velocity is low, pulling of the head will become more independent of variations in the amplitude of the tracking error signal.
FIG. 4 is a graph corresponding to FIG. 7. Line c in this graph is where a suitable offset is applied under conditions similar to line b in FIG. 7, which is also shown in FIG. 4. It is seen that the head converges on the target track although the velocity is the same when the mode is switched to the tracking operation (tangential line). FIG. 5 is a graph corresponding to FIG. 8.
As described hereinbefore, seek time can be stably shortened in accordance with the present invention.
In addition, the allowable range of head velocity at which the head can be pulled to the target track can be expanded.
Further, a failure in pulling, which is caused by optic-axial offset of objective lenses in optical disks, and by nonuniformity in disk groove shapes and gain fluctuations in actuators and sensors in disk storage units, can be prevented.
Further, a tracking control, capable of stably pulling a head to a target track even if the head reaches the target track at high velocity, can be provided in accordance with the present invention.
While the invention has been particularly shown and described with reference to preferred embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention: | A disk storage unit according to the present invention comprises a disk for storing data, a head for at least reading data stored on the disk, a controller for controlling a seek operation in which the head moves from a current track to a target track and a tracking operation in which the head tracks the target track after reaching the target track, based on a tracking error signal, and a device for adding a dc offset to the tracking error signal so that head drive power having a direction opposite that of the seek operation and corresponding to the velocity of the head in the seek operation is generated after the head has reached the target track and the seek operation has been switched to the tracking operation. | 6 |
BACKGROUND
[0001] This invention relates generally to processor-based systems.
[0002] A processor-based system may include a display having a display screen. The display screen may display images generated by a processor-based system. Generally, there is no way to interact with the images generated on that system in any extensive fashion.
[0003] For example touch screens are available which enable the user to touch the display screen and thereby to select an icon displayed on the screen. However, this operation requires a specialized display screen. The display screen must include a sensor which detects the presence of the user's finger and thereby correlates that presence to the selection of an appropriate icon. Thus, the interaction that is possible is a direct result of the special configuration and construction of the display screen itself. Such interaction is not possible with any display screen. Moreover, additional expense may be incurred in providing a display screen which is also sensitive to touch.
[0004] With the advent of three dimensional graphics, relatively life-like images may be produced in computer displays. Ideally, the user would like to interact with those graphics. Currently, electronic interaction is possible through keyboards and other input devices.
[0005] Thus, there is a need for a way to physically interact with the images displayed on a computer display screen.
BRIEF DESCRIPTION OF THE DRAWINGS
[0006] FIG. 1 is a perspective view of one embodiment of the present invention;
[0007] FIG. 2 is a perspective view of the embodiment shown in FIG. 1 , with the user interacting with an image displayed on a display screen;
[0008] FIG. 3 is a block diagram in accordance with one embodiment of the present invention; and
[0009] FIG. 4 is a flow chart for software in accordance with one embodiment of the present invention.
DETAILED DESCRIPTION
[0010] Referring to FIG. 1 , an element 10 enables a user whose hand is indicated at A to interact with images being displayed on a computer display screen. In one embodiment, the element 10 includes a handle 12 that fits in the palm of the user's hand and presents a trigger 24 for operation by the user's index finger. Transversely connected to the handle 12 , a telescoping shaft may include a proximal portion 14 and a distal portion 16 .
[0011] The shaft portions 14 and 16 may be splined to prevent relative rotation. In one embodiment, the portions 14 and 16 are spring biased to extend apart unless constrained.
[0012] A sensor housing 18 may be coupled to the distal portion 16 . The sensor housing 18 may include detectors 22 that may detect the positions of spring biased light pens 20 . The spring biased light pens 20 telescope in and out of the housing 18 in the direction of the arrows. As the pens 20 extend in and out of the housing 18 , the detectors 22 detect the position of each pen 20 relative to the housing 18 .
[0013] Thus, turning to FIG. 2 , the element 10 is shown in position pressed against the display screen 28 of a computer display 26 . The display 26 may be any type of computer display including a computer monitor.
[0014] In this case, the pens 20 are pressed against the screen 28 . Because three equally spaced pens 20 are utilized, the angular orientation of the element 10 with respect to the display screen 28 may be determined based on the extension of each of the pens 20 with respect to the housing 18 . However in the alternative embodiments, the element orientation detectors and the light pens may be separate devices.
[0015] In some embodiments, the display screen 28 , which may be glass, may be covered by another surface which may be flat and transparent. However, other shapes and transparencies may be used.
[0016] In the illustrated embodiment, the element 10 interacts with an image 30 displayed on the display screen 28 . In one embodiment, the image 30 may be a scissors-type gripper. The gripper image 30 may grip a second image 32 such as a test tube. The user may press against the screen 28 to cause the images 30 and 32 to appear to extend “deeper” into the display screen 28 . In actuality, the images 30 and 32 are altered to create this effect under computer control.
[0017] Thus, the exact position of the pens 20 on the display screen 28 may be determined in a fashion described hereinafter. The angular orientation and extension of the portions 14 and 16 may also be determined. As a result, the orientation of the element 10 with respect to the image 30 may be determined. This information may be utilized to allow the element 10 to seemingly interact with and actually alter the image 30 . For example, as the user presses the element against the screen 28 against the spring bias between the portions 14 and 16 , the image 30 may appear to extend further into the screen 28 as if the image 30 , were actually part of the physical element 10 . This allows the user, whose hand is indicated at A, to apparently physically interact with images 30 , 32 displayed on the display screen 28 .
[0018] Referring to FIG. 3 , the element 10 may be coupled to a processor-based system 39 through a video pass through box 38 in one embodiment. The video pass through box 38 may receive video control signals from the processor-based system 39 headed for the display 26 . Thus, the pass through box 38 may receive the vertical and horizontal sync signals that the system 39 may generate to control the display 26 in one embodiment of the present invention. In addition, the pass through box 38 receives the detector 22 signals from the element 10 .
[0019] The pass through box 38 may be of the type conventionally utilized with light pens to determine a location on a display screen selected by a light pen. An example of such a box is the PXL-2000 USB External Interface available from FastPoint Technologies, Inc., Stanton, Calif. However, other techniques for identifying the location of the light pens 20 on the display screen 28 may also be used.
[0020] The pass through box 38 may receive signals from the light pens 20 a , 20 b and 20 c. Each light pens 20 may detect light signals generated by one or more pixels making-up the display screen 28 . The optical transducers 34 convert those light signals into electrical signals and provide them to the video pass through box 38 . In one embodiment, the signals pass through the video pass through box 38 into a serial port such as a Universal Serial Bus hub 50 coupled to the processor-based system 39 .
[0021] The detectors 22 a - c that detect the extension of the pens 20 with respect to the housing 18 may also generate signals. In one embodiment, the detectors 22 may be rheostats that generate a signal indicative of the extent of spring biased extension of the pens 20 from the housing 18 . Those analog signals may be converted to digital signals by the analog-to-digital converters 36 . The digital signals may also pass through the pass through box 38 and the hub 50 to the processor-based system 39 .
[0022] A detector 22 d may be associated with the portions 14 and 16 to determine their relative extension. Thus, the detector 22 d determines the relative positions of the portions 14 and 16 which may be the result of the user pressing the element 10 into the screen 28 or releasing that force. In one embodiment, all of the detectors 22 may be rheostats.
[0023] Finally, user operation of the trigger 24 may generate signals. Each time the user operates the trigger 24 , the extent of trigger deflection and its duration may be encoded into an analog signal. That analog signal may be converted into a digital signal by the analog-to-digital converter 36 e. This digital signal, like the other signals discussed above, is passed through the video pass through box 38 and the hub 30 to the processor-based system 39 .
[0024] The processor-based system 39 may include a processor 44 coupled to system memory 46 . The processor 44 may be coupled to a bus 42 which in turn is coupled to a graphics interface 40 in one embodiment. Signals generated by the processor 40 may be passed through the graphics interface 40 and the video pass through box to the video display 26 .
[0025] A bridge 48 may also be coupled to the bus 42 . In one embodiment, the bridge 48 may be coupled to the hub 50 as well as a storage device 52 which may be a hard disk drive. The storage device 52 may store software 54 for controlling the interaction between the element 10 and the display screen 28 .
[0026] The video pass through box 38 may receive the graphics signals intended for display on the video display 26 . Thus, the box 38 may receive the vertical and horizontal sync signals as well. By extracting those vertical and horizontal sync signals, and comparing their timing to the timing of signals received from the light pens 20 , the system 39 can determine the location of the light pens 20 on the display screen 28 . In particular, the light pens 20 receive a flash of light when a particular underlying display screen 28 pixel is activated. The pixels may be sequentially activated in response to vertical and horizontal sync signals generated by the system 39 . Thus, the time from vertical and horizontal sync signal to light flash is indicative of screen 28 position of the pens 20 .
[0027] In one embodiment, a vertical sync signal is generated to start each new frame. A horizontal sync signal is generated with the beginning of each line. Thus, by knowing when a light signal is received by a light pen 20 relative to when a corresponding vertical sync signal and horizontal sync signal was detected, the system 39 may determine the vertical and horizontal coordinates of each light pen 20 . The pass through box 38 may do the initial analysis to determine the pen 20 position or may simply forward the raw information onto the system 39 for analysis.
[0028] The software 54 , shown in FIG. 4 , may begin in one embodiment, by determining whether the light pen data has been received as indicated in diamond 56 . If so, that data may be correlated to the vertical and horizontal sync signals as indicated in block 58 . The frame and screen coordinates for each particular received light pen signal may then be determined as indicated in block 60 .
[0029] Next, a check at diamond 62 indicates whether the detector 22 data was received, as indicated in diamond 62 . If so, the angle of the element 10 with respect to the display screen 26 may be calculated. In addition, the distance of a handle 12 from the display screen is also calculated as indicated in block 64 , using the shaft data from the portions 14 and 16 .
[0030] A check a diamond 66 determines whether trigger activation has occurred. If so, an image such as the gripper image 30 may be altered. For example, the gripper image 30 may appear to “open”. For each unit of trigger activation in terms of time, a corresponding operation may be created virtually on the display screen 28 in one embodiment.
[0031] Based on the change in relative position between the portions 14 and 16 , relative motion of a handle 12 with respect to the display screen, or rotation of the handle 12 relative to the display screen, the orientations or images 30 and 32 may be recalculated. The signals that generate the images 30 and 32 may be received and the revised signals may be transmitted to the display screen 26 for a display as indicated in block 70 .
[0032] The images 30 and 32 may be caused to move inwardly, as if they were coupled to the element 10 , by pressing the element 10 harder against the screen 28 . This action is detected by the detector 22 d . Similarly, the element 10 may be rotated or angularly adjusted with respect to the screen causing a corresponding change in position of the images 30 and 32 . This action is detected by the detectors 22 a - c. Similarly, operation of the trigger 24 may cause the preprogrammed change in one or both images 30 and 32 .
[0033] In each case, three dimensional manipulation of the element 10 may result in a corresponding three dimensional alteration of an image 30 or 32 . As a result, it may seem that the element 10 is physically linked to an image 30 or 32 .
[0034] While the present invention has been described with respect to a limited number of embodiments, those skilled in the art will appreciate numerous modifications and variations therefrom. It is intended that the appended claims cover all such modifications and variations as fall within the true spirit and scope of this present invention. | A physical element may be caused to appear to interact with an image displayed on a computer display screen. The position of the element with respect to the display screen may be determined automatically. The user can then manipulate the element to cause an image, which may appear to be connected to the element, to be altered. Therefore, the user gets the impression that the element is capable of interacting and altering an image displayed on the display screen. | 6 |
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority to Japanese Application No. 2003-334680, filed Sep. 26 , 2003 .
BACKGROUND OF THE INVENTION
[0002] This invention relates to semiconductor devices in general and, in particular, to those especially well adapted for use in the electronic driver circuits of electric motors, among other applications. More particularly, the invention pertains to an integrated semiconductor device incorporating transistors or like active elements, featuring provisions for inhibiting or restricting the action of parasitic transistors under certain foreseeable conditions in use of the semiconductor device in motor drive systems or the like.
[0003] Japanese Unexamined Patent Publication No. 63-18660 is hereby cited as teaching a motor drive system ( FIG. 1 ) representing a typical application of the instant invention. The motor drive system has a required number of motor driver circuits of like construction coupled one to each of the motor coils in star connection. Each motor driver circuit has four transistors in addition to two diodes. When the motor driver circuits were fabricated in the form of an integrated semiconductor circuit ( FIG. 2 ), a parasitic transistor was unavoidably created between two neighboring ones of the transistors of each motor driver circuit. The parasitic transistor conducted when the output of the driver circuit had a negative potential, preventing the motor drive system from driving the motor exactly as required.
[0004] In order to prevent the appearance of the parasitic transistor, the cited Japanese patent application suggests the creation of a floating region between the two transistors in question which are formed island-like in the semiconductor substrate and which are separated therefrom via pn junctions. The floating region was intended to accomplish its purpose by making the space between the transistors higher in resistance. An objection to this prior art device is its inordinate space requirement between the transistors, adding substantively to the size of the semiconductor device.
SUMMARY OF THE INVENTION
[0005] The present invention has it as a primary object to prevent the undesired action of parasitic transistors in integrated semiconductor devices of the kind under consideration.
[0006] A more specific object of the invention is to provide integrated semiconductor devices of the kind under consideration which can be made significantly less in size than the noted prior art device having a floating region, in order to attain the first recited object to the same extent.
[0007] Briefly, the present invention concerns an integrated semiconductor device having a common semiconductor region of a first conductivity type formed in a semiconductor substrate. Formed in the common semiconductor region are a first and a second semiconductor element such as transistors. The first semiconductor element has a first island-like semiconductor region of a second conductivity type, opposite to the first conductivity type, which is contiguous to the common semiconductor region. The second semiconductor element has a second island-like semiconductor region of the second conductivity type contiguous to the common semiconductor region. The first and the second semiconductor element are spaced from each other via the common semiconductor region, with the consequent creation of a parasitic transistor by the common semiconductor region of the first conductivity type and the first and the second island-like semiconductor region of the second conductivity type. The invention provides performance-enhancer means connected to the second island-like semiconductor region and the common semiconductor region for preventing the conduction of the parasitic transistor when the second island-like semiconductor region is less in potential than the common semiconductor region.
[0008] In one embodiment of the invention the performance-enhancer means comprises a performance-enhancer transistor having an emitter connected to the second island-like semiconductor region, a collector connected to a separation subregion of the common semiconductor region between the first and the second island-like region, and a base grounded. In another embodiment a third island-like semiconductor region of the second conductivity type is formed in the semiconductor substrate in the adjacency of the second island-like semiconductor region. Another parasitic transistor is therefore intentionally created between the second and the third island-like region for counteracting the undesired parasitic transistor between the first and the second island-like region.
[0009] Either way, when the second island-like region grows less in potential than the common semiconductor region, so does the common semiconductor subregion between the first and the second island-like region. The parasitic transistor is thus prevented from acting to interfere with the desired functioning of the semiconductor device.
[0010] The above and other objects, features and advantages of this invention will become more apparent, and the invention itself will best be understood, from a study of the following description and appended claims, with reference had to the attached drawings showing the preferred embodiments of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] FIG. 1 is a schematic electrical diagram of a known motor drive system including motor driver circuits to each of which the present invention finds typical application, the diagram being explanatory of a parasitic transistor appearing in each motor driver circuit when the latter is fabricated in the form of an integrated circuit;
[0012] FIG. 2 is a fragmentary section through a known integrated semiconductor circuit incorporating one of the motor driver circuits of FIG. 1 , the section revealing those two transistors of the motor driver circuit between which is created the parasitic transistor;
[0013] FIG. 3 is a sectional view similar to FIG. 2 but shown together a schematic electrical diagram including a performance-enhancer transistor according to the present invention as well as the associated electrical connections;
[0014] FIG. 4 is a plan view of an integrated semiconductor circuit incorporating the performance-enhancer transistor of FIG. 3 in addition to the four transistors of each motor driver circuit of FIG. 1 ;
[0015] FIG. 5 is a section through the integrated circuit of FIG. 4 , taken along the line A-A therein and shown together with the means needed for use as one of the motor driver circuits of FIG. 1 ; and
[0016] FIG. 6 is a half sectional and half diagrammatic illustration similar to FIG. 5 but showing an alternate embodiment of the invention.
DETAILED DESCRIPTION
[0017] It is considered essential that the difficulties heretofore encountered in the part be shown and described in some more detail, the better to make clear the features and advantages of the instant invention. The prior art motor drive system of FIG. 1 is shown to have three driver circuits A 1 , A 2 and A 3 for controlled energization of respective coils L 1 , L 2 and L 3 which in fact form inductive loads. Only the first motor driver circuit A 1 is shown in detail in FIG. 1 , it being understood that the other two are of identical make.
[0018] The representative first driver circuit A 1 comprises four npn transistors Q 1 , Q 2 , Q 3 and Q 4 , two diodes D 1 and D 2 , and a resistor R 1 . The first transistor Q 1 at the driver stage has its base connected to the control signal input S 1 of the first driver circuit A 1 , its collector to a dc supply terminal +V cc via the resistor R 1 , and its emitter to the base of the second transistor Q 2 at the output stage. This second transistor Q 2 has its emitter grounded, and its collector to the output T 1 of the first driver circuit A 1 . The third transistor Q 3 , also at the driver stage, has its base connected to the control signal input S 1 , its collector to the supply terminal +V cc , and its emitter to the base of the fourth transistor Q 4 at the output stage. The fourth transistor Q 4 has its collector connected to the supply terminal +V cc , and its emitter to the first driver circuit output T 1 . The diodes D 1 and D 2 are connected reversely in parallel with the base-emitter junction of the second and fourth transistors Q 2 and Q 4 , respectively.
[0019] The second and third motor driver circuits A 2 and A 3 have their own control signal inputs S 2 and S 3 , and their own dc supply terminals +V cc , connected thereto. The outputs T 1 , T 2 and T 3 of the three motor driver circuits A 1 -A 3 are connected respectively to the motor coils L 1 -L 3 which on the other hand are interconnected to form a star network.
[0020] The three motor coils L 1 -L 3 are selectively energized by the switching actions of the transistors Q 2 and Q 4 of the first driver circuit A 1 as well as the unshown equivalent transistors of the second and third driver circuits A 2 and A 3 . (The unshown transistors of the second and third driver circuits A 2 and A 3 will be hereinafter identified by the same reference characters as those of the corresponding transistors Q 1 -Q 4 of the first driver circuit A 1 .) For instance, when the fourth transistor Q 4 of the first driver circuit A 1 and the second transistor Q 2 of the third driver circuit A 3 are both conductive, current will flow along the path comprising the supply terminal +V cc , fourth transistor Q 4 and output T 1 of the first driver circuit A 1 , the first motor coil L 1 , the third motor coil L 3 , and the second transistor Q 2 of the third driver circuit A 3 .
[0021] If now the fourth transistor Q 4 is turned off, an electromotive force will develop inversely across the first motor coil L 1 , with the result that the first driver circuit output T 1 has a negative potential. Assuming further that the first and second transistors Q 1 and Q 2 are now both nonconductive, the collector of the first transistor Q 1 will have approximately the same potential as does the supply terminal +V cc with the consequent development of a potential difference between the collector of the first transistor Q 1 and the output T 1 . As indicated by the broken lines in FIG. 1 , a parasitic npn transistor Q x may then be created between the collectors of the first and second transistors Q 1 and Q 2 if the first driver circuit A 1 is in the form of an integrated semiconductor circuit. This parasitic transistor will conduct when the driver circuit output T 1 is at negative potential, causing the motor to be driven in other than the desired way.
[0022] Why the parasitic transistor Q x appears between the collectors of the transistors Q 1 and Q 2 will become better understood by referring to FIG. 2 . Shown here is a section through that part of an integrated semiconductor device where there are formed the transistors Q 1 and Q 2 of the FIG. 1 motor driver circuit A 1 in the immediate vicinity of each other. The generally flat semiconductor substrate 1 has a common (or grounded) semiconductor region 4 of a first conductivity type (shown as p) which is exposed at both of the pair of opposite major surfaces 2 and 3 of the substrate. Two semiconductor regions 5 and 6 of a second conductivity type (shown as n) are formed island-like in the common semiconductor region 4 so as to be exposed at the first major surface 2 . These n-type island-like semiconductor regions 5 and 6 are isolated from the p-type semiconductor region 4 by pn junctions. These and other semiconductor regions are conventionally created in the substrate 1 by epitaxial growth and impurity diffusion.
[0023] The term “common semiconductor region 4 ” used above comprehends both the inherently p-type substrate subregion 4 a , which is exposed at the substrate major surface 3 , and the p + -type separation subregion 4 b which lies on the side of the other substrate major surface 2 . The complete common semiconductor region 4 could be called a separation or isolation region.
[0024] The first island-like region 5 has formed therein an n-type collector region 7 , a p-type base region 8 , and an n-type emitter region 9 , for providing the first transistor Q 1 . The collector region 7 comprises an n-type collector subregion 7 a of relatively high resistance and an n + -type collector subregion 7 b of relatively low resistance. The collector subregion 7 a is constituted of either part or whole of the first island-like region 5 .
[0025] The second island-like region 6 has likewise formed therein an n-type collector region 10 , a p-type base region 11 , and an n-type emitter region 9 , for providing the second transistor Q 2 . The collector region 10 comprises an n-type collector subregion 10 a of relatively high resistance and an n + -type collector subregion 10 b of relatively low resistance. The collector subregion 10 a is constituted of either part or whole of the second island-like region 6 .
[0026] It is understood that the integrated semiconductor device of FIG. 2 has also formed therein the transistors Q 3 and Q 4 , diodes D 1 and D 2 , etc., of the FIG. 1 motor driver circuit A 1 in addition to the first and second transistors Q 1 and Q 2 . The third transistor Q 3 is not shown in FIG. 2 , however, because it is unessential for the explanation of the parasitic transistor Q x for which this figure is intended. The fourth transistor Q 4 is depicted as a schematic electronic symbol on the outside of the semiconductor substrate 1 for illustrative convenience.
[0027] FIG. 2 further indicates diagrammatically that the first transistor Q 1 has its p-type base region 8 connected to the control signal input S 1 , its n-type emitter region 9 to the p-type base region 11 of the second transistor Q 2 by way of a conductor 13 , and its low-resistance collector subregion 7 b to its supply terminal +V cc via the noted resistor R 1 . The second transistor Q 2 has its n-type emitter region 12 grounded by way of a conductor 14 , and its low-resistance collector subregion 10 b connected to the driver output T 1 and thence to the motor coil L 1 . The p-type common semiconductor region 4 is grounded.
[0028] A closer study of FIG. 2 will reveal the parasitic transistor Q x which, as indicated by the broken lines, may appear between the transistors Q 1 and Q 2 . The parasitic transistor Q x is of npn configuration, manifesting itself as the p-type common semiconductor region 4 is interposed in part between the n-type first island-like region 5 , which forms the collector of the first transistor Q 1 , and the n-type second island-like region 6 which forms the collector of the second transistor Q 2 . This parasitic transistor Q x is nonconductive when the driver output T 1 and second island-like region 6 have both a positive potential with respect to that of the common semiconductor region 4 , because then the parasitic transistor has its base-emitter junction reverse-biased. When the driver output T 1 and second island-like region 6 have a negative potential, on the other hand, the parasitic transistor Q x has its base-emitter junction forward-biased and so is conductive.
[0029] An obvious solution to the problem of how to inhibit the appearance, or restrict the action, of the parasitic transistor might seem to place the two island-like regions 5 and 6 sufficiently far away from each other for these purposes. This solution is unsatisfactory because it would add very much to the size of the semiconductor substrate 1 . As has been stated, Japanese Unexamined Patent Publication No. 63-18660, supra, suggests a somewhat more practical solution: The creation of an n-type floating region in that part of the p-type common semiconductor region 4 which lies between the island-like regions 5 and 6 . The floating region is designed to make the spacing between the island-like regions 5 and 6 higher in resistance. Admittedly, this known remedy makes less space requirement between the island-like regions 5 and 6 than does the first suggested solution; nevertheless, an inconveniently large space is still required in order for the floating region to perform its intended function to the full.
[0030] The present invention succeeds in eliminating practically any undesired activity of parasitic transistors in integrated semiconductor devices of the kind in question without these inconveniences of the prior art. What follows is the description of some preferred embodiments.
[0031] Embodiment of FIGS. 3-5
[0032] FIG. 3 shows one such embodiment having an improved integrated semiconductor device for use in the motor drive system of FIG. 1 , the improved semiconductor device being complete with voltage application means constituting a feature of the invention. A comparison of FIGS. 2 and 3 will reveal that the sectionally depicted parts (revealing the transistors Q 1 and Q 2 with the phantom parasitic transistor therebetween) of the integrated semiconductor devices according to the prior art and to this invention are of the same construction. Like reference characters are therefore used to denote like parts in both FIGS. 2 and 3 .
[0033] Referring more specifically to FIG. 3 , the generally flat semiconductor substrate 1 of the improved semiconductor device has a common semiconductor region 4 of a first conductivity type (shown asp) which is exposed at both of the pair of opposite major surfaces 2 and 3 of the substrate. Two island-like semiconductor regions 5 and 6 of a second conductivity type (shown as n) are formed in the common semiconductor region 4 so as to be exposed at the first major surface 2 . These n-type island-like regions 5 and 6 are separated from the p-type semiconductor region 4 by pn junctions. These and other semiconductor regions are conventionally created in the substrate 1 by epitaxial growth and impurity diffusion.
[0034] As has been mentioned in connection with FIG. 2 , the term “common semiconductor region 4 ”, as used herein and in the claims appended hereto, should be construed to mean both the inherently p-type substrate subregion 4 a and the p + -type separation subregion 4 b However, the separation subregion 4 b may be separately referred to as part of the common semiconductor region 4 .
[0035] The first island-like region 5 has formed therein an n-type collector region 7 , a p-type base region 8 , and an n-type emitter region 9 , for providing the first transistor Q 1 as the first semiconductor element. The collector region 7 comprises an n-type collector subregion 7 a of relatively high resistance and an n + -type collector subregion 7 b of relatively low resistance. The high-resistance collector subregion 7 a is constituted of either part or whole of the first island-like region 5 . The low-resistance collector subregion 7 b is constituted of an n + -type embedded part and an n + -type lead-out or plug part, the latter being exposed at the major surface 2 of the substrate 1 . The base region 8 is created island-like in the low-resistance collector subregion 7 a . The emitter region 9 is created island-like in the base region 8 .
[0036] The second island-like region 6 has likewise formed therein an n-type collector region 10 , a p-type base region 11 , and an n-type emitter region 9 , for providing the second transistor Q 2 as the second semiconductor element. The collector region 10 comprises an n-type collector subregion 10 a of relatively high resistance and an n + -type collector subregion 10 b of relatively low resistance. The high-resistance collector subregion 10 a is constituted of either part or whole of the second island-like region 6 . The low-resistance collector subregion 10 b is constituted of an n + -type embedded part and an n + -type lead-out or plug part, the latter being exposed at the major surface 2 of the substrate 1 . The base region 11 is formed island-like in the low-resistance collector region 10 a . The emitter region 12 is formed island-like in the base region 11 .
[0037] It is understood that the integrated semiconductor device of FIG. 3 has also formed therein the transistors Q 3 and Q 4 , diodes D 1 and D 2 , etc., of the FIG. 1 motor driver circuit A 1 in addition to the first and second transistors Q 1 and Q 2 . The third transistor Q 3 of the moor driver circuit A 1 is not shown in FIG. 3 , however, because it is not directly associated with the parasitic transistor Q x or with the means for inhibiting its action. The fourth transistor Q 4 is depicted diagrammatically and outside of the semiconductor substrate 1 for illustrative convenience. Also shown diagrammatically and outside of the semiconductor substrate 1 for illustrative convenience is the noted voltage application means or performance-enhancer means constituting the feature of this invention. The voltage application means include an additional transistor Q a which, unlike the other transistors Q 1 -Q 4 , does not take in motor driving but which contributes toward enhancement of the performance of the motor drive system through nullification of the parasitic transistor Q x . This transistor Q a will therefore be hereinafter referred to as the performance-enhancer transistor in contradistinction from the other transistors Q 1 -Q 4 .
[0038] FIG. 3 further indicates diagrammatically that the first transistor Q 1 has its p-type base region 8 connected to the control signal input S 1 , its n-type emitter region 9 to the p-type base region 11 of the second transistor Q 2 by way of a conductor 13 , and its low-resistance collector subregion 7 b to its supply terminal +V cc via the noted resistor R 1 . The second transistor Q 2 has its n-type emitter region 12 grounded by way of a conductor 14 , and its low-resistance collector subregion 10 b to the driver output T 1 and thence to the motor coil L 1 . The p-type common semiconductor region 4 is grounded.
[0039] Excepting the performance-enhancer transistor Q a , the improved semiconductor device of FIG. 3 as so far described is of the same construction as that of the prior art device of FIG. 2 . As a consequence, a parasitic transistor Q x may appear between the transistors Q 1 and Q 2 as the p-type common semiconductor region 4 is interposed in part between the n-type first island-like region 5 , which forms the collector of the first transistor Q 1 , and the n-type second island-like region 6 which forms the collector of the second transistor Q 2 . This parasitic transistor Q x is nonconductive as aforesaid when the driver output T 1 and second island-like region 6 have both a positive potential with respect to that of the common semiconductor region 4 , because then the parasitic transistor has its base-emitter junction reverse-biased. When the driver output T 1 and second island-like region 6 have a negative potential, on the other hand, the parasitic transistor Q x has its base-emitter junction forward-biased and so is conductive. The performance-enhancer transistor Q a according to the invention is designed to prevent the conduction of the parasitic transistor Q x , as will become apparent as the description proceeds.
[0040] Of npn construction, the performance-enhancer transistor Q a has its emitter connected by way of a conductor 15 as connection means both to the driver output T 1 and to a first point P 1 on that surface of the low-resistance collector subregion 10 b of the second transistor Q 2 which is exposed at the first major surface 2 of the substrate 1 . The collector of the performance-enhancer transistor Q a is connected by way of a conductor 16 as connection means to a second point P 2 on that surface of the common semiconductor region 4 , or of the p + -type separation subregion 4 b , which is exposed at the first major surface 2 of the substrate 1 . More precisely, the second point P 2 is on the exposed surface of that part of the p + -type separation subregion 4 b as a first separation subregion which lies intermediate the island-like regions 5 and 6 . The base of the performance-enhancer transistor Q a is grounded on one hand and, on the other, connected by way of a conductor 17 as connection means to a third point P 3 on that surface of the common semiconductor region 4 , or of that part of the p + -type separation subregion 4 b as a second separation subregion, which is exposed at the first major substrate surface 2 . The ground is higher in potential than the driver output T 1 when the driver output T 1 has a negative potential. The third point P 3 lies across the first island-like region 5 from the second point P 2 . The performance-enhancer transistor Q a conducts when the driver output T 1 goes negative during operation of the motor drive system, in order to prevent the conduction of the parasitic transistor Q x as discussed in more detail hereinbelow.
[0041] When the first transistor Q 1 conducts in response to the motor control signal supplied through the input S 1 , so does, too, the second transistor Q 2 . When the first transistor Q 1 is nonconductive, so is the second transistor Q 2 .
[0042] As has been explained with reference to FIGS. 1 and 2 , the driver output T 1 may go negative with respect to the ground potential in this type of motor drive system. The negative potential at the driver output T 1 will make the emitter of the performance-enhancer transistor Q a less in potential than its base, resulting in conduction therethrough. The collector potential (equal to the potential at the second point P 2 ) of the performance-enhancer transistor Q a during conduction is expressed as:
V p2 =−V t1 −V CE(sat)
where
V p2 =potential at the second point P 2 ; −V t1 =negative potential at the driver output T 1 ; V CE(sat) =collector-emitter saturation voltage of the performance-enhancer transistor Q a .
[0047] As is clear from the equation above, the potential at the second point P 2 is negative when the collector-emitter voltage V CE(sat) of the performance-enhancer transistor Q a is less than the absolute value of the negative potential that can occur at the driver output T 1 of the motor driver circuit. The potential at this second point P 2 is equivalent to the base potential of the parasitic transistor Q x . Thus the pn junction between the base and emitter of the parasitic transistor Q x is short-circuited by the performance-enhancer transistor Q a , with the consequent prevention or substantial limitation of conduction through the parasitic transistor Q x .
[0048] As indicated by the arrow in FIG. 3 , the collector current I c of the performance-enhancer transistor Q a mostly flows from third point P 3 to second point P 2 through the substrate subregion 4 a adjacent the first transistor Q 1 . This collector current I c can be lessened in magnitude by making the substrate subregion 4 a appropriately high in resistance.
[0049] FIG. 4 is a plan view of the improved integrated semiconductor device of FIG. 3 , revealing not only the first and second transistors Q 1 and Q 2 but also the third and fourth transistors Q 3 and Q 4 as well as the performance-enhancer transistor Q a in their correct relative positions in the substrate 1 . FIG. 5 is a section through the improved integrated semiconductor device, taken along the line A-A in FIG. 4 . In this latter figure, however, the electrical connections among the required parts of the transistors Q 1 , Q 2 and Q a are shown diagrammatically on the outside of the semiconductor device for illustrative convenience only; in practice, such connections are made by conductors in the insulating layer, not shown, formed on the surface of the semiconductor substrate 1 . These connections are of course the same as those depicted in FIG. 3 .
[0050] It will be observed from both FIGS. 4 and 5 that the performance-enhancer transistor Q a is disposed on that side of the first transistor Q 1 which is opposite to the side where lies the second transistor Q 2 . The performance-enhancer transistor Q a comprises an n-type third island-like semiconductor region 20 , an n + -type collector region 21 formed in the island-like region 20 , a p-type base region 22 formed also in the island-like region 20 , and an n-type emitter region 23 formed in the base region 22 .
[0051] The performance-enhancer transistor Q a might seem to add much to the size of the semiconductor device. The additional size required by this transistor Q a is, however, significantly less than that demanded by the prior art floating region between the transistors Q 1 and Q 2 . Furthermore the functioning of the performance-enhancer transistor Q a is much more positive and reliable than that of the prior art floating region.
[0052] The advantages gained by this first embodiment of the invention may be summarized as follows:
[0053] 1. The performance-enhancer transistor Q a positively prevents the parasitic transistor Q x from becoming active when the driver output T 1 goes negative in potential, so that the motor drive system is protected from erroneous operation, resulting in more accurate control of motor operation.
[0054] 2. Current loss due to the performance-enhancer transistor Q a is reducible by making the substrate region 4 a appropriately high in resistance.
[0055] 3. The integrated semiconductor device is appreciably reduced in size compared to the prior art devices that attain the same objective by spacing the transistors Q 1 and Q 2 far enough away from each other or by providing a floating region therebetween.
Embodiment of FIG. 6
[0056] FIG. 6 shows another preferred form of integrated semiconductor device according to the invention, in a sectional view similar to FIG. 5 . This alternative embodiment does not have the performance-enhancer transistor Q a of the FIGS. 3-5 embodiment but does incorporate, instead, a third n-type island-like semiconductor region 30 in the semiconductor substrate 1 . This third island-like region 30 is designed for intentional creation of an additional parasitic transistor Q b in coaction with the preexisting second transistor Q 2 in order to preclude the harmful effect of the undesired parasitic transistor Q x . The additional parasitic transistor Q b will therefore be hereinafter referred to as the performance-enhancer parasitic transistor.
[0057] Referring more specifically to FIG. 6 , the third island-like region 30 is arranged on that side of the second transistor Q 2 which is opposite to the side where there lies the first transistor Q 1 . The undesired parasitic transistor Q x exists between the two neighboring transistors Q 1 and Q 2 . Formed in the third island-like region 30 is an npn transistor comprising an n + -type collector region 34 , a p-type base region 35 , and an n-type emitter region 36 . The transistor thus formed in the third island-like region 30 lends itself to any appropriate use in each specific application of this integrated circuit. It is not, however, the complete transistor in the third island-like region 30 , but only its collector (or n + -type semiconductor region) 34 , that coacts with the n + -type collector subregion 10 b of the second transistor Q 2 and the common semiconductor region 4 to provide the desired npn-type performance-enhancer parasitic transistor Q b .
[0058] In order to counteract the undesired parasitic transistor Q x by the performance-enhancer parasitic transistor Q b , a point P 5 on the exposed surface of the n + -type semiconductor region 34 is connected by way of a conductor 31 to the noted point P 2 on the exposed surface of that part of the separation subregion 4 b as a first separation subregion of the common semiconductor region 4 which lies between the transistors Q 1 and Q 2 . Further a point P 4 on the exposed surface of that part of the separation subregion 4 b which lies between the second and third island-like regions 6 and 30 is grounded by way of a conductor 32 . Still further a point P 3 on the exposed surface of that part of the separation subregion 4 b as a second separation subregion which lies outside of the transistor Q 1 is also grounded by way of a conductor 33 . The point P 1 on that surface of the low-resistance collector subregion 10 b of the second transistor Q 2 is connected as in the previous embodiment to the emitter of the fourth transistor Q 4 and to the driver output T 1 .
[0059] Thus, when the driver output T 1 has a negative potential −V t1 , so does the point P 1 . The result is the forward biasing of the pn junction between the points P 1 and P 4 , that is, between the n + -type collector subregion 10 b of the second transistor Q 2 and the p + -type separation subregion 4 b . Thereupon the performance-enhancer parasitic transistor Q b will conduct. The potential at the point P 5 on the n + -type semiconductor region 34 can therefore be defined as:
V p5 =−V t1 −V CE(sat)
where V p5 =potential at the point P 5 ; V CE(sat) =collector-emitter saturation voltage of the performance-enhancer parasitic transistor Q b .
[0063] The point P 5 is connected by way of the conductor 31 to the point P 2 on that part of the separation subregion 4 b which lies between the transistors Q 1 and Q 2 . The potential V p2 at the point P 2 is therefore equal to the potential V p5 at the point P 5 . Hence:
V p2 =V p5 =−V t1 −V CE(sat) .
[0064] The point P 2 will have a negative potential when the driver output T 1 has a negative potential whose absolute value is higher than the collector-emitter saturation voltage V CE(sat) of the performance-enhancer parasitic transistor Q b . Thus, as in the FIGS. 3-5 embodiment, the conduction of the undesired parasitic transistor Q x will be reduced to a minimum.
[0065] Notwithstanding the foregoing detailed disclosure it is not desired that the present invention be limited by the exact details of the attached drawings or the description thereof. For example, in the FIGS. 3-5 embodiment, the performance-enhancer transistor Q a could be provided external to the semiconductor substrate 1 for further reduction in the size of the substrate itself. The performance-enhancer npn transistor Q a itself might be replaced by other semiconductor elements such as the field-effect transistor or static induction transistor. Also, the other transistors Q 1 -Q 4 might be replaced by other semiconductor elements such as the field-effect transistor or static induction transistor, respectively. Additionally, in the alternate embodiment of FIG. 6 , the fabrication of the transistor in the third island-like semiconductor region 30 is not an essential feature of this invention, all that is required being that there be the n + -type region 34 for creation of the performance-enhancer parasitic transistor Q b in cooperation with the n + -type collector subregion 10 b of the second transistor Q 2 . The n + -type region 34 could occupy the whole of the island-like region 30 .
[0066] All these and other modifications or alterations of the illustrated embodiments which will readily occur to the semiconductor specialists are intended in the foregoing disclosure. The invention should therefore be construed broadly and in a manner consistent with the fair meaning or proper scope of the claims which follow. | An electric motor drive system is disclosed which includes a required number of motor driver circuits connected one to each motor armature coil. Fabricated in the form of an integrated circuit, each such motor driver circuit has a parasitic transistor unavoidably created between two neighboring transistors. The parasitic transistor would become conductive when the driver circuit output had a negative potential, adversely affecting the driver circuit operation. An additional transistor is provided in one embodiment of the invention in order to inhibit such action of the parasitic transistor. Becoming conductive when the driver circuit output goes negative, the additional transistor prevents conduction through the parasitic transistor. Another parasitic transistor is intentionally created in another embodiment for the same purpose. | 7 |
This application is a continuation of prior application Ser. No. 08/409,274, filed on Mar. 23,1995, now abandoned.
BACKGROUND OF THE INVENTION
This invention relates to a method and apparatus for consistently and accurately aligning knitting needles and other knitting elements on warp knitting machines. Traditionally, skilled technicians are needed to check knitting needle spacing, knitting needle height, knitting guide spacing, knitting guide height, and needle to guide interference as well as back-to-front guide and needle alignment. This is a very painstaking process in which the knitting machine technician was forced to visually estimate these parameters. This alignment took a considerable period of time and was very inaccurate. This inaccuracy results in significant quality problems.
This present invention solves these problems in a manner not disclosed in the known prior art.
SUMMARY OF THE INVENTION
An apparatus and method for knitting needle and guide alignment which provides a means for consistently and accurately aligning knitting needles and other knitting elements on warp knitting machines. This includes checking for needle spacing, needle height, guide spacing, guide height, and needle to guide interference. This may also check back-to-front needle and guide alignment. This system includes a video camera for acquiring an image of the knitting elements and a means of displaying this image on an electronic display. There is a linear actuator with associated control system for accurately positioning the video camera to accomplish the above tasks.
An advantage of this invention is to provide accurate alignment of knitting needles and knitting guides.
Another advantage of this invention is to reduce the time required for aligning knitting needles and knitting guides.
These and other advantages will be in part apparent and in part pointed out below.
BRIEF DESCRIPTION OF THE DRAWINGS
The above, as well as other objects of the invention, will become more apparent from the following detailed description of the preferred embodiments of the invention when taken together with the accompanying drawings, in which:
FIG. 1 is a perspective view of an apparatus for aligning knitting needles and knitting guides incorporating the novel features of the present invention along with a view of the right side of a warp knitting machine in conjunction with a computer, monitor, and keyboard on an electronics cart;
FIG. 2 is an perspective view of the left hand side of a knitting machine including a viewing screen and a digital keypad;
FIG. 3 is an isolated perspective view of the video camera, mounting means for the video camera, and a linear actuator;
FIG. 4 is an isolated side elevational view of a knitting machine including the novel knitting needle and knitting guide alignment mechanism incorporating the novel features of the present invention including video camera, linear actuator, locating arm, and viewing screen;
FIG. 5 is an isolated side view of the knitting mechanism, including double needles and the six guide members located above in an arc-like configuration;
FIG. 6 is a front isolated view of a series of knitting needles and one series of knitting guides;
FIG. 7 is a flow chart of the initialization steps for a knitting needle and knitting guide alignment tool of the present invention; and
FIG. 8 is a continuation of the flow chart of FIG. 7, which describes the main loop of the software program for aligning knitting needles and knitting guides incorporating the novel features of the present invention.
Corresponding reference characters indicate corresponding parts throughout the separate views of the drawings.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to the accompanying drawings, initially to FIG. 1, which is a perspective view of the right side of a typical warp knitting machine and the knitting needle and alignment apparatus of the present invention. This combination is generally denoted by numeral 10. The warp knitting machine is specifically denoted by numeral 12. A typical nonlimiting example of a warp knitting machine includes a LIBA®, Model Number BG-506-DPLM, Model Number DG-508-DPLM, and Model Number RACOP-D8-MK-DPLM. LIBA® warp knitting machines are manufactured by LIBA Maschinenfabrik, GmbH, located at D95112 Naila-Oberklingensporn, Germany. Referring now to both FIGS. 1 and 2, warp knitting machine 12 includes a rectangular base member 6 in the center of which is a vertical support beam 7 having a rectangular top member 8 attached thereto that is parallel to the rectangular base member 6. In FIG. 1, on the right hand side of the warp knitting machine 12, there are a series of five rotatable shaft support brackets designated by numerals 72, 74, 76, 78, and 80, respectively. These five rotatable shaft support brackets 72, 74, 76, 78, and 80, are equally spaced and extend from the left to right. Rotatable shaft support brackets 72, 74, 76, 78, and 80 are perpendicularly attached to the rectangular base member 6 and vertically extend upward. These five rotatable shaft support brackets 72, 74, 76, 78, and 80 hold rotatable shafts 34, 36, 38 in a position parallel to the base member 6. A first row of knitting needles is designated by numeral 40 and is positioned parallel and behind the three rotatable shafts 34, 36, 38 and just below the top rectangular member 7. Positioned parallel to and in front of the three rotatable shafts 34, 36, and 38 is a first arm rest for mechanics designated by numeral 42.
As shown in FIG. 2, this is duplicated on the left side of the knitting machine 12 with an additional series of three rotatable shafts 134, 136, and 138. These three rotatable shafts 134, 136, and 138 are also supported by five rotatable shaft support brackets with the numeral designations of 172, 174, 176, 178, and 180. These five rotatable shaft support brackets 172, 174, 176, 178, and 180 are equally spaced and extend from left to right. There is also a second arm rest for mechanics 142 positioned in front of the three rotatable shafts 134, 136, and 138, as well as a second row of knitting needles 140 positioned parallel and behind the three rotatable shafts 134, 136, 138 and just below the top rectangular member 7.
Referring again to FIG. 1, there is a linear actuator 56 that is removedly attached to the knitting machine 12 by a pair of mounting brackets 48 and 50, respectively. Mounting bracket 48 is attached to the base member 6 of the knitting machine 12 by means of clamp 44. Mounting bracket 50 is attached to the base member 6 of the knitting machine 12 by means of clamp 46. The linear actuator 56 is stabilized by means of two locating arms 52 and 54, respectively. Locating arm 52 goes over rotating shafts 34 and 36 and rests underneath rotating shaft 38. As shown in FIG. 4, there is a hardened steel pad 81 attached to locating arm 52 that is in contact with rotating shaft 38. There is a hardened steel V-block 82 that rests over rotating shaft 36 at its position underneath locating arm 52. This is replicated for locating arm 54 with a similar hardened steel pad and hardened steel V-block (not shown).
As shown in FIG. 2, this same structure is replicated on the left hand side of warp knitting machine 12 with mounting brackets 148 and 150. The linear actuator 56 can be moved to this side and attached thereto. There is again a pair of clamps 144 and 146 for attaching the mounting brackets 148 and 150 to the warp knitting machine 12. There is also a pair of locating arms 152 and 154 attached to mounting brackets 148 and 150, respectively. Locating arm 152 goes over the second arm rest for the mechanic 142 and rotating shafts 134 and 136 while positioned against rotating shaft 138. As again shown in FIG. 4, there is a hardened steel pad 181 located between locating arm 152 and rotating shaft 138. There is a hardened V-block 182 positioned over rotating shaft 136 and underneath locating arm 152. This is replicated for locating arm 154 with a similar hardened steel pad and hardened steel V-block (not shown).
A central component is the utilization of a video camera 58 as shown in FIGS. 1, 3, and 4 that is able to move back and forth in a direction parallel to and along the length of the first row of knitting needles 40 if the linear actuator 56 is attached to mounting brackets 48 and 50 or in a direction parallel to and along the length of the second row of knitting needles 140 if the linear actuator 56 is attached to mounting brackets 148 and 150.
A typical nonlimiting example of the video camera 58 would be a PULNIX, Model Number TM7CN manufactured by Pulnix America, Inc., located at 1330 Orleans Drive, Sunnyvale, Calif. 94089. The image in the video camera 58 is enlarged by means of a 2X extender 242. This 2X extender 242 functions as a magnifier so that the image produced by video camera 58 will be literally doubled. A nonlimiting example of a 2X extender is FUJINON® CE2O-1 MODEL V2.OX PROD 1486 manufactured by Fuijinon, Inc., located at Ten High Point Drive, Wayne N.J. 07470. A lens 244 is attached to the 2X extender 242. A typical nonlimiting example of a lens would be a Computer MCA7518APC 75 millimeter F1.8 TV lens manufactured by Chugai Boyeki America, located at 55 Mall Drive, Commack, N.Y. 11775. As shown in FIGS. 3 and 4, located between the video camera 58 and the 2X extender 242 is an extension tube 240. A typical nonlimiting example of an extension tube is FUJINON®, Model VETK PROD 0826 manufactured by Fuijinon, Inc., located at Ten High Point Drive, Wayne N.J. 07470. The utilization of an extension tube and extender can vary depending on the needle size, the spacing of the needles, and the other parameters of the warp knitting machine 12.
Two additional hardware elements that prove helpful include a grid 88 that is superimposed on the video camera image and an image invertor 86. All of these components are hardware devices that alter the video image. A typical non-limiting example of a grid 88 would be a JAVELIN MODEL JV2000GRD manufactured by Javelin Electronics, located at 19831 Magellan Drive, Torrance, Calif. 90502. A typical nonlimiting example of an image invertor 86 would include an AD DIGIFLIP, Model AD1426 SN 319714 manufactured by American Dynamics, located at 10 Corporate Drive, Orangeburg, N.Y. 10962. The image invertor 86 rotates the video image by one hundred and eighty degrees. The grid 88 places a specified number of intersecting vertical and horizontal lines over the video image. This essentially functions as template for aligning knitting needles and guides. As shown in FIG. 1, there is a first video cable 90 that connects the video camera 58 to the invertor 86. A second video cable 92 connects the invertor 86 to the grid 88. There is a fourth video cable 94 that is connected to a video monitor 14.
As shown in FIG. 3, a video camera 58 is mounted on video camera support block 70. Video camera support block 70 is mounted on a horizontal adjustable mechanism as generally denoted by numeral 60. Horizontal adjustable mechanism 60 includes a top plate 64 overlapping a bottom plate 66. Top plate 64 has a threaded member 65 and bottom plate 66 has a threaded member 67. There is an adjustment bolt 68 extending between threaded member 65 and threaded member 67 to provide horizontal adjustment for the video camera 58. This horizontal adjustable mechanism 60 can also be termed a kinematic base. A typical nonlimiting example of a kinematic base is Model M-BK-3, manufactured by Newport Corporation located at 1791 Deere Avenue, Irvine, Calif. 92714.
Bottom plate 66 is mounted on an orthogonal hinge jack 62 for vertical adjustment. A typical nonlimiting example of a orthogonal hinge jack 62 for vertical adjustment is manufactured by Newport Corporation located at 1791 Deere Avenue, Irvine, Calif. 92714., Model M-270.
The orthogonal hinge jack 62 is mounted on a support saddle 63. The support saddle 63 moves on top of a linear actuator 56. This allows the video camera 58 to traverse the full length of the knitting machine 12. Linear actuator 56 includes a ball screw (not shown) that is rotated by a stepper motor 57. There is a ball nut (not shown) that rides on top of the ball screw along the length of the knitting machine 12. There are a series of ball bearings (not shown) in between the ball screw and the ball nut. The carriage saddle 63 is fixedly attached to the ball nut. There is also an encoder 84 for accurately determining the position of the carriage saddle 63. A typical nonlimiting example of a stepper motor 57 is manufactured by Warner Electric Model SS2000-06. A typical nonlimiting example of a stepper motor 57 with encoder 84 is Warner Electric Model M093-FF206-CS. A typical example of a carriage manufactured by Warner Electric is Model RAPIDTRAK TS09. Warner Electric is located at 449 Gardner Street, South Beloit, Ill. 61080.
As shown in FIG. 1, there is a first electrical cable 30 that connects the stepper motor 57 and the linear actuator 56 to a computer 20. Computer 20 can be any of a wide variety of commercially available microprocessors. A typical nonlimiting example would be a GATEWAY® 20 MHZ 386SX computer, although there are advanced 486 and PENTIUM® Models that would be preferred. PENTIUM® is a registered trademark of the Intel Corporation located at 3065 Bowers Avenue, Santa Clara, Calif. 95054. GATEWAY® computers are manufactured by Gateway 2000, located at 610 Gateway Drive, North Sioux City, S.Dak. 57049. Computer 20 is located on electronics cart 18. Also positioned on the electronics cart 18 is a keyboard 16 and the video monitor 14. A typical nonlimiting example of a keyboard 16 would be Industrial Computer Source Model DI016, manufactured by Industrial Computer Source, located at 10180 Scripps Ranch Boulevard, San Diego, Calif. 92131. A typical nonlimiting example of a video monitor 14 would be a Mitsubishi Model HL6605TK manufactured by Mitsubishi Electronics America, Incorporated located at 991 Knox Street, Torrance, Calif. 90502. The computer 20 would have to actuate a motor controller (not shown), which is a board that is a part of the computer 20. A typical nonlimiting example of a motor controller is B & B Motors and Controllers Model PC-DSP-100, manufactured by B & B Motors and Controllers, located at Apple Hill Commons, Burlington, Conn. 06013. Instead of using the keyboard 16, the actuator 56 may also be controlled by a hand held programmable key pad 24. As shown in FIG.2, a programmable key pad 24 is attached by a second electrical cable 28 to the computer 20.
As shown in FIGS. 2 and 4, a liquid crystal diode monitor 22 is attached to an attachment bracket 197 which is pivotally attached to a support bracket 195 that is also pivotally attached to a linear slide 193. A typical nonlimiting example of a liquid crystal diode monitor 22 would be a Sharp Model 6M-40U manufactured by Sharp Electronics Corporation, located at Sharp Plaza, Mahwah, N.J. 07430. Linear slide 193 can move back and forth across a linear rectangular slide 185. Linear slide 185 is held against knitting machine 12 by means of a series of three switchable magnets 183. These magnets 183 can be turned off or on to enable the operator to move this liquid crystal diode monitor 22 to either side of the knitting machine 12. There are a series of three brackets 187, 188, and 189, respectively, that connect the linear rectangular slide 185 to the series of three switchable magnets 183. This liquid crystal diode monitor 22 is attached to grid 88 by means of a fourth video cable 26. As previously stated, grid 88 is attached to invertor 86 by means of second video cable 92 and invertor 86 is attached to video camera 58 by means of first video cable 90, as shown in FIG. 1.
The knitting machine 12 is set up as a double bar knitting machine, as shown in FIG. 5. There is a first row of knitting needles 40 and a second row of knitting needles 140 that alternate up and down along the Z axis. The first row of knitting needles 40 is attached to the knitting machine 12 by a series of caps and trick plates 203. The second row of knitting needles 140 is attached to knitting machine 12 by a second row of caps and trick plates 205. As shown in FIG. 5, for each pair of knitting needles 40 and 140, respectively, a series of six rows of guides interact therewith that are denoted as guides 206, 210, 214, 218, 222, and 226, respectively. As shown in FIGS. 5 and 6, the row of guides designated by numeral 206 are attached to a row of molded guide support bases 207. These molded guide support bases 207 are attached to the guide bar assembly 230 by means of a first row of attachment screws 208. The second row of guides 210 is attached to a second row of molded guide support bases 211. These molded guide support bases 211 are attached to the guide bar assembly 230 by means of a second row of attachment screws 212. The third row of guides 214 are connected to a third row of molded guide support bases 215. The third row of molded guide support bases 215 are attached to the guide bar assembly 230 by means of a third row of attachment screws 216. A fourth row of guides 218 is attached to the fourth row of molded guide support bases 219. The fourth row of molded guide support bases is attached to the guide bar assembly 230 by means of a fourth row of attachment screws 220. The fifth row of guides 222 is connected to a fifth row of molded guide support bases 223. The fifth row of molded guide support bases 223 is attached to the guide bar assembly 230 by means of a fifth row of attachment screws 224. Finally, the sixth row of guides 226 is connected to a sixth row of molded guide support bases 227. The sixth row of molded guide support bases 227 is attached to the guide bar assembly 230 by means of a sixth row of attachment screws 228. The guide bar assembly 230 can rock as well as move back and forth. In other words, the guide bar assemble can move along the x, y, and z axis.
Referring again to FIG. 6, the first row of guides 206 is shown in the upper position located between the first row of knitting needles 40 extending from the bottom. The first row of guides 206 are attached to a first row of molded guide support bases 207 and fixedly attached to the guide bar assembly 230 by means of a first row of attachment screws 208. The first row of knitting needles 40 are attached to a first row of knitting needle caps and trick plates 203 by means of a series of a first row of knitting needle attachment screws 232. The goal is to align the row of knitting needles 40 first. This involves adjusting the needles 40 until they are properly and equally spaced, vertical, and all the same height. The gauge of the needles 40 ranges from 16 to 28 needles per inch. Once the needles 40 are aligned, the first row of guides 206 are lowered into the gaps between the needles 40. The interference typically ranges from one-eighth (1/8) to one-fourth (1/4) of an inch and depends on the geometry of the needles and guides as well as the style of the fabric to be knitted. The guides 206 are then adjusted so that they equally split the distance between two adjacent needles. The guides 206 must also be adjusted so that they are the same and proper height. In addition, back-to-front needle and guide alignment will also have to be ascertained. Once the guides 206 have been aligned, the guides 206 are removed from the guide bar assembly 230, and the next row of guides 210 are aligned in a similar fashion. This procedure continues for guides 214, 218, 222, and 226. The second row of needles 140 are aligned and the guides 206, 210, 214, 218, 222, and 226 are again checked for alignment with the second row of needles 140.
FIG. 7 details a flow chart of the initialization process for the computer program. The first step is the initialization of the hardware (Block 310). The next step is run the video grid setup (Block 312) which receives the input for the chosen grid size (Block 314). The next step is to establish a set-up menu (Block 316). This involves receiving user input (Block 324). This input involves providing the needle gauge (Block 318), as well as the microstep size which is a predetermined amount of movement of the video camera (Block 320) as well as an increment size (Block 322) which is for moving a certain number of knitting needles per increment. The next step is to wait for input (Block 328) from the "Go To Home Limit" key (Block 326). This will let the camera 58 go to the first limit switch 247 nearest the stepper motor 57 on the left end of the linear actuator 56, as shown in FIG. 1 (Block 330). There is a second limit switch 248 on the far right end of the linear actuator 56. The camera 58 will continue to move down the linear actuator 56 until the first limit switch 247 is activated. The computer software will continue looping until an input is received that the home needle is found, which can be an arbitrary needle selected by the operator (Blocks 332 and 334). After the home needle is found (Block 338), the operator can push the "Set Home Needle" button (Block 336) to initialize the program and provide input to the computer as to the position of the home needle. Initialization is now complete and the system is ready for utilization.
The main body of the computer program is flowcharted in FIG. 8. The first step is to start the main loop (Block 340). There is a "Wait Until a Key is Hit" (Block 344) that requires the striking of the desired key (Block 342) then reading the ASCII code of that key (Block 346). There are fourteen different functions possible, or in other words, fourteen different keys that can be pushed. The first function is to move the camera 58 in a positive direction until it strikes the first limit switch 247 (Block 348). The second function is to move the camera 58 in a negative direction until it strikes the second limit switch 248 (Block 350). The third function is to toggle the camera 58 in either the positive or negative direction (Block 352). The fourth function is to move the camera 58 in the negative direction the distance of one knitting needle (Block 354). The fifth function is to move the camera 58 in the positive direction the distance of one knitting needle (Block 356). The sixth function is to move the camera 58 by a microstep in a positive direction (Block 358) and the seventh function is to move the camera 58 by a microstep in a negative direction (Block 360). A microstep is defined by taking a previously inputted number and dividing that number by one thousand. This number was provided in the step indicated by Block 320 in FIG. 7. The eighth and ninth functions are respectively, moving by a certain number of needles in the negative direction (Block 362) depending upon your previously inputted increment size found in (Block 322) or moving by a certain number of needles in the positive direction (Block 364). You can move a negative number of needles (Block 362) or positive number of needles (Block 364).
The tenth function is positive jogging (Block 366), which will occur until either the end of travel is reached with the activation of limit switch 247 or the emergency stop button is pushed or the jog button is pushed again which acts to quit the jogging process (Blocks 370 and 372). This then stops the jogging process (Block 374). The computer then loops back to Block 344 and starts over again.
The eleventh function is negative jogging (Block 368), which will occur until either the end of travel is reached with the activation of limit switch 247 or the emergency stop button is pushed or the jog button is pushed again which acts to quit the jogging process (Blocks 370 and 372). This then stops the jogging process (Block 374). The computer then loops back to Block 344 and starts over again.
The twelfth function (Block 376) is repeating the set-up routine found in FIG. 7 in Blocks 322, 320, and 318. This involves receiving input (Block 378) involving a new needle gauge (Block 384), a new microstep size (Block 382), and a new increment size (Block 380). The computer then loops back to Block 344 and starts over again allowing the operator to use thirteen other functions with these new input parameters.
The thirteenth function (Block 386) is similar to that found in the initialization portion of the program (FIG. 7) is going to the home needle. This is identical similar to routine found in Blocks 332, 334, 338, and 336, as previously described. The camera 58 will move along the linear actuator 56 until the desired knitting needle is directly in the middle of the video image. This involves looping through Blocks 388 and 390. When the home needle is found (Block 394), the home needle key can be reset (Block 392). The computer then loops back to Block 344 and starts over again.
The last and fourteenth function is to stop all motion (Block 396) and end the program (Block 398).
As this invention may be embodied in several forms without departing from the spirit or essential character thereof, the embodiments presented herein are intended to be illustrative and not descriptive. The scope of the invention is intended to be defined by the following appended claims, rather than any descriptive matter hereinabove, and all embodiments of the invention which fall within the meaning and range of equivalency of such claims are, therefore, intended to be embraced by such claims. | An apparatus and method for knitting needle and guide alignment for consistently and accurately aligning knitting needles and other knitting elements on warp knitting machines. This includes checking for needle spacing, needle height, guide spacing, guide height, and needle to guide interference. This may also check back-to-front needle and guide alignment. This system includes a video camera for acquiring an image of the knitting elements and a means of displaying this image on an electronic display. There is a linear actuator with associated control system for accurately positioning the video camera to accomplish the above tasks | 3 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a method and apparatus for detecting and correcting an unbalanced condition in the rotating drum of a washing machine. It is particularly applicable to a washing machine having a drum on an axis other than vertical.
2. Description of the Related Art
Washing machines utilize a generally cylindrical perforated basket for holding clothing and other articles to be washed that is rotatably mounted within an imperforate tub mounted for containing the wash liquid, which generally comprises water, detergent or soap, and perhaps other constituents. In some machines the basket rotates independently of the tub and in other machines the basket and tub both rotate. In this invention, the rotatable structure is referred to generically as a “drum”, including the basket alone, or the basket and tub, or any other structure that holds and rotates the clothing load. Typically, an electric motor drives the drum. Various wash cycles introduce into the clothing and extract from the clothing the wash liquid, usually ending with one or more spin cycles where final rinse water is extracted from the clothes by spinning the drum.
It is common to categorize washing machines by the orientation of the basket. Vertical-axis washing machines have the basket situated to spin about a vertical axis relative to gravity. Horizontal-axis washing machines have the basket oriented to spin about an essentially horizontal axis, relative to gravity.
Both vertical and horizontal-axis washing machines extract water from clothes by spinning the drum about their respective axes, such that centrifugal force extracts water from the clothes. Spin speeds are typically high in order to extract the maximum amount of water from the clothes in the shortest possible time, thus saving time and energy. But when clothing and water are not evenly distributed about the axis of the drum, an imbalance condition occurs. Typical spin speeds in a vertical axis washer are 600-700 RPM, and in a horizontal axis washer at 1100 or 1200 RPM. Moreover, demand for greater load capacity fuels a demand for larger drums. Higher spin speeds coupled with larger capacity drums aggravates imbalance problems in washing machines, especially in horizontal axis washers. Imbalance conditions become harder to accurately detect and correct.
As the washing machine drum spins about its axis, there are generally two types of imbalances that it may exhibit: static imbalance and dynamic imbalance. FIGS. 1-4 illustrate schematically different configurations of imbalance in a horizontal axis washer comprising a drum 10 having a horizontal geometric axis 12 . The drum 10 is suspended for rotation within a cabinet 14 having a front 16 (where access to the interior of the drum is normally provided) and a back 18 . A drive point 19 (usually a motor shaft) is typically located at the back 18 .
FIGS. 1( a ) and ( b ) show a static imbalance condition generated by a static off-balance load. Imagine a load 20 on one side of the drum 10 , but centered between the front 16 and the back 18 . A net moment torque t causes the geometric axis 12 to rotate about the axis of rotation 22 of the combined mass of the drum 10 and the load 20 at an angular velocity ω, resulting in displacement d of the drum 10 . This displacement, if minor, is often perceived as a vibration at higher speeds. The suspension system is designed to handle such vibration under normal conditions. Static imbalances are detectable at relatively slow speeds such as 85 or 90 RPM.
Dynamic imbalance is more complex and may occur independently of the existence of any static imbalance. FIGS. 2-4 illustrate several different conditions where dynamic imbalances exist. In FIGS. 2( a ) and ( b ), imagine a dynamic off balance load of two identical masses 30 , one on one side of the drum 10 near the front 16 and the other near the back 18 . In other words, the masses 30 are on a line 32 skewed relative to the geometric axis 12 . The net moment torque t 1 about the geometric axis 12 is zero, so there is no static imbalance. However, there is a net moment torque t 2 along the geometric axis 12 , so that the drum will tend to wobble about some axis other than the geometric axis. If the moment is high enough, the wobble can be unacceptable.
FIGS. 3( a ) and ( b ) illustrates a combined static and dynamic imbalance caused by a front off-balance load. Imagine a single load 40 in the drum 10 toward the front 16 . There is a net moment torque t 1 about the geometric axis 12 , resulting in a static imbalance. There is also a moment torque t 2 along the geometric axis 12 , resulting in a dynamic imbalance. The resulting motion of the drum is a combination of displacement and wobble.
FIGS. 4( a ) and ( b ) illustrates a combined static and dynamic imbalance caused by a back off-balance load. Imagine a single load 50 in the drum 10 toward the back 18 . There is a net moment torque t 1 about the geometric axis 12 , resulting in a static imbalance. There is also a moment torque t 2 along the geometric axis 12 , resulting in a dynamic imbalance. The resulting motion of the drum is a combination of displacement and wobble.
Unfortunately, dynamic imbalance is often detectable only at higher speeds. Both vertical and horizontal axis machines exhibit static imbalances, but dynamic imbalances are a greater problem in horizontal-axis machines. Imbalance-caused vibrations result in greater power consumption by the drive motor, excessive noise, and decreased performance.
Many solutions have been advanced for detecting and correcting both static and dynamic imbalances. Correction is generally limited to aborting the spin, reducing the spin speed, or changing the loads in or on the basket. Detection presents the more difficult problem. It is known to detect vibration directly by employing switches, such as mercury or micro-switches, which are engaged when excessive vibrations are encountered. Activation of these switches is relayed to a controller for altering the operational state of the machine. It is also known to use electrical signals from load cells on the bearing mounts of the basket, which are sent to the controller. Other known methods sample speed variations during the spin cycle and relate it to power consumption. For example, it is known to have a controller send a PWM (Pulse Width Modulated) signal to the motor controller for the drum, and measure a feedback signal for RPM achieved at each revolution of the drum. Fluctuations in the PWM signal correspond to drum imbalance, at any given RPM. Yet other methods measure power or torque fluctuations by sensing current changes in the drive motor. Solutions for detecting static imbalances by measuring torque fluctuations in the motor abound. But there is no correlation between static imbalance conditions and dynamic imbalance conditions; applying a static imbalance algorithm to torque fluctuations will not accurately detect a dynamic imbalance. For example, an imbalance condition caused by a front off balance load (see FIG. 3 ) will be underestimated by existing systems for measuring static imbalances. Conversely, an imbalance condition caused by a back off balance load (see FIG. 4 ) will be overestimated by existing systems for measuring static imbalances.
Moreover, speed, torque and current in the motor can all fluctuate for reasons unrelated to drum imbalance. Commonly owned U.S. Pat. No. 6,640,372 presents a solution to factoring out conditions unrelated to drum imbalance by establishing a stepped speed profile where average motor current is measured at each step and an algorithm is applied to predetermined thresholds for ascertaining an unbalanced state of the drum. Corrective action by the controller will reduce spin speed to minimize vibration. The particular algorithm in the '372 patent may be accurate for ascertaining static imbalances. However, is not entirely accurate for horizontal axis washing machines because it does not accurately ascertain the various dynamic imbalance conditions.
There is yet another unacceptable condition of a rotating washer drum that involves neither a static or dynamic imbalance, but establishes a point distribution that can deform the drum. A point distribution condition is illustrated in FIG. 5( a ) and ( b ). Imagine two identical loads 60 distributed evenly about the geometric axis 12 , and on a line 52 normal to the geometric axis. There is no moment torque, either about the geometric axis 12 , or along the geometric axis. Thus, there is no imbalance detectable at any speed. However, centrifugal force F acting on the loads 60 will tend to deform the drum. If the drum were a basket rotating inside a fixed tub as is common in many horizontal axis washers, the basket may deform sufficiently to touch the tub, degrading performance and causing unnecessary wear and noise.
Another problem in reliably detecting imbalances in production washers regardless of axis is presented by the fact that motors, controllers, and signal noise vary considerably from unit to unit. Thus, for example, a change in motor torque in one unit may be an accurate correlation to a given imbalance condition in that unit, but the same change in torque in another unit may not be an accurate correlation for the same imbalance condition. In fact, the problems of variance among units and signal noise are common to any appliance where power measurements are based on signals that are taken from electronic components and processed for further use.
There exists a need in the art for an imbalance detection system for a washing machine, particularly horizontal axis washing machines, which can effectively, efficiently, reliably and accurately sense any imbalance condition, and sense other obstructions that may adversely affect performance. Further, there is a need for accurately determining stable and robust power information that can accommodate variations in motors, controllers and signal noise from unit to unit.
SUMMARY OF THE INVENTION
These problems and others are solved by the present invention of a method of determining an imbalance condition in a washing machine having a rotatable drum driven by a variable speed motor. The method comprises several steps, the first of which is establishing a speed profile for the washing machine, having at least three increasing speed steps. Then one operates the motor to rotate the drum sequentially through the three speed steps, measuring the power output of the motor at each speed step, calculating an average power output by averaging the power output at the first and second speed steps, calculating the difference between the power output at the third step and the average power output, comparing the difference to a predetermined threshold difference value, and sending a signal indicative of an imbalance condition if the difference exceeds the threshold difference value.
Preferably, the signal causes a reduction in rotation speed of the drum to a level where the difference is equal to or less than the threshold difference value. Also, preferably, the washing machine will have a controller, so a step of determining an adapted power profile for the last speed step can be done, where the controller in response to the signal causes the motor to track the adapted power profile. The method is particularly applicable to a horizontal axis washer where the drum axis is not vertical.
In another aspect of the invention, a washing machine having a rotatable drum driven by a variable speed motor, a predetermined speed profile comprising increasing speed steps, a predetermined maximum power output for each speed step, and a threshold difference value for each speed step above the second speed step, incorporates an improved method comprising the steps of
A. operating the motor to accelerate rotation of the drum to the first of the increasing speed steps,
B. measuring a first power output of the motor at the first speed step,
C. comparing the measured first power output to the predetermined maximum power output for the first speed step,
D. sending a signal indicative of an imbalance condition if the difference exceeds the predetermined maximum power output for the first speed step,
E. operating the motor to accelerate rotation of the drum to the second of the increasing speed steps if the difference does not exceed the predetermined maximum power output for the first speed step,
F. measuring a second power output of the motor at the second speed step,
G. calculating an average power output by averaging the power output at the first and second speed steps,
H. comparing the measured second power output to the predetermined maximum power output for the second step,
I. sending a signal indicative of an imbalance condition if the difference exceeds the predetermined maximum power output for the second step,
J. operating the motor to accelerate rotation of the drum to the next of the increasing speed steps if the difference does not exceed the predetermined maximum power output for the second speed step,
K. measuring a next power output of the motor at the next speed step,
L. calculating the difference between the power output at the next step and the average power output,
M. comparing the measured next power output to the predetermined maximum power output for the next step,
N. sending a signal indicative of an imbalance condition if the difference exceeds the predetermined maximum power output for the next step,
O. comparing the difference in step L. to the predetermined threshold difference value for the next speed step if the difference does not exceed the predetermined threshold difference value for the next speed step,
P. sending a signal indicative of an imbalance condition if the difference in step L. exceeds the predetermined threshold difference value for the next step, and
Q. repeating steps J. through P. until a maximum reference speed is achieved.
Preferably, the washing machine is a horizontal axis washing machine. In a further aspect, the invention includes a washing machine having a rotatable drum, a variable speed motor for driving the drum, and a programmable controller for controlling the motor. The controller is programmed to operate the motor to rotate the drum sequentially through at least three speed steps of a predetermined speed profile, measure the power output of the motor at each speed step, calculate an average power output by averaging the power output at the first and second speed steps, calculate the difference between the power output at the third step and the average power output, compare the difference to a predetermined threshold difference value, and send a signal indicative of an imbalance condition if the difference exceeds the threshold difference value.
BRIEF DESCRIPTION OF THE DRAWINGS
In the drawings:
FIGS. 1( a ) and ( b ) is a schematic illustration of the concept of static imbalance.
FIGS. 2( a ) and ( b ) is a schematic illustration of the concept of dynamic imbalance caused by a dynamic off balance load.
FIGS. 3( a ) and ( b ) is a schematic illustration of the concept of dynamic imbalance caused by a front off balance load.
FIGS. 4( a ) and ( b ) is a schematic illustration of the concept of dynamic imbalance caused by a back off balance load.
FIGS. 5( a ) and ( b ) is a schematic illustration of the concept of a point distribution condition.
FIG. 6 is a perspective view of a horizontal axis washing machine where the invention can be applied.
FIG. 7 is a graphic illustration of a speed profile and sampling windows according to the invention.
FIG. 8 is a graphic illustration of a power profile superimposed on the speed profile of FIG. 7 in a balanced condition.
FIG. 9 is a flow diagram schematically illustrating a method for detecting unbalance conditions according to the invention.
FIG. 10 is a graphic illustration of power v. speed for four unbalanced loads and a balanced load after application of the method according to the invention.
FIG. 11 is a graphic illustration similar to FIG. 7 showing the fourth speed step and adapted speed and power after corrective action for an unbalanced load.
FIG. 12 schematically shows a circuit for measuring DC bus voltage of a motor control inverter according to the invention.
FIG. 13 schematically shows a circuit for measuring DC bus current of a motor control inverter according to the invention.
FIG. 14 is a flow chart illustrating an offset calibration method according to the invention.
DETAILED DESCRIPTION
Imbalance Detection
FIG. 6 shows a front load, horizontal axis washing machine 100 of the type most suited for the present invention. But for incorporating the method according to the invention in the washing machine 100 , the physical structure is conventional. Internally, the washing machine 100 has a drum 102 comprising a rotating perforated basket 104 , nested within an imperforate tub 106 that holds wash liquid during the various cycles of a washing process. It will be understood that the term “drum” refers to the rotatable structure that holds the clothing and wash liquid, whether that structure is the basket 104 alone or both the basket 104 and tub 106 , or any other equivalent structure. A variable speed motor 108 typically drives the drum 102 with pulleys through either a direct drive system or a belt. The tub 106 is typically supported by a suspension system (not shown) that can include springs, dampers, and the like.
During a spin cycle where water is extracted from clothes in the drum by centrifugal force, the drum 102 is accelerated to rotate at relatively high speeds, on the order of 1100 RPM. If the load in the drum 102 is unevenly distributed in a manner to create a static imbalance as in FIGS. 1( a ) and ( b ) the drum will oscillate about its geometric axis. Such oscillation can be detected early in the spin cycle at low speed using known methods, e.g., the method disclosed in the '372 patent. If the oscillation exceeds a predetermined threshold, the machine can be slowed or stopped to correct the imbalance. This is an infrequent problem in horizontal axis machines, however, because the load tends to balance itself about the geometric axis during acceleration of the basket 104 .
Nevertheless, regardless of distribution of the load about the geometric axis, it is not unusual for the load to be distributed unevenly from one end of the drum 102 to the other, creating a dynamic imbalance as in FIGS. 2-4 . Unlike static imbalance in a horizontal axis washer, a dynamic imbalance is not self-correcting and does not normally appear until higher speeds are achieved. If the imbalance is large enough and remains uncorrected, the resulting vibration, noise, and attendant risks are manifest. Also in larger capacity washers that can hold up to 10 Kg of mass, there is a risk that the basket will deform and touch the tub as the basket spins at high speed (see FIG. 5 ). The earlier an imbalance condition or a potential tub deformation can be detected, the earlier corrective action can be applied consistent with effective performance, and without significantly sacrificing speed.
Accordingly, the present invention as illustrated in FIGS. 7-14 provides a method for detecting a dynamic imbalance early enough to effectively avoid unacceptable vibration conditions and optimize rotational speed for any given load.
A predetermined speed profile 120 is established as shown in FIG. 7 . The speed profile 120 is characterized by a series of steps 122 , each step having a speed ramp 124 and a speed plateau 126 . For the present embodiment, speed step 1 has a reference speed of 590 RPM, speed step 2 is 760 RPM, speed step 3 is 960 RPM and speed step 4 is the design speed of 1100 RPM for the spin cycle. Each speed ramp 124 is a dynamic period where the drum speed accelerates from a lower speed step to a higher speed step, and where the motor has to deliver a higher power (or torque) to accelerate the drum. Each speed plateau 126 is a static period where the drum achieves a constant speed, and where the motor must deliver only enough power to overcome system friction or drag and torque caused by an imbalance. Actual speed will generally follow the reference speed as the motor drives the drum, when the motor is controlled by a controller (not shown). FIG. 8 shows a sample power profile 128 superimposed on the speed profile 120 with a balanced load.
In general, a washing machine can be considered a rigid body that is not an energy sink. Thus, the amount of energy absorbed by the machine's suspension system in passive mode is limited. When the energy absorbed by the suspension exceeds a threshold value, the excess energy will dissipate as vibration, noise and heat. In this case, the washer will behave abnormally. Thus, tracking the power profile 128 related to the speed profile 120 can indirectly monitor imbalance conditions in the washing machine 100 .
In this invention, an algorithm has been developed for monitoring real-time power. The power input information is calculated from the DC bus voltage and DC bus current of the motor control inverter (see the discussion below). A micro-controller or DSP is utilized to handle this signal processing. A variable speed motor control system drives the drum to track the reference speed profile in a closed loop status. A filtering technique is provided to reduce any noise impacts in signal processing (see below).
Looking again at FIG. 7 , the speed profile 120 has four speed steps 122 to reach the design spin speed. Each speed step 122 has a sampling window 130 defined over time, preferably during the speed plateau 126 . Preferably, the starting time for each sampling window 130 is determined empirically for a given machine by running a maximum rated load for the machine over the speed profile 120 and ascertaining when the power profile 128 achieves stability after completion of the ramp up for each speed step. The sampling rate and total samples taken are preferably the same for all sampling windows. An average power level k can be calculated by
P k = ∑ i = 1 n p ki n
where k=1, 2, 3, 4 for each respective sampling window, P ki =instantaneous power reading; and n=total sampling numbers.
Thus, four power samples P 1 , P 2 , P 3 , and P 4 as shown in FIG. 7 can be obtained during the spin cycle. Each power sample can be considered to have two parts. One part is the power for overcoming the system friction and drag. The other part is the power needed to overcome imbalance, whether static or dynamic. Although there is some interaction between the two parts, a distinction is a reasonable assumption in this case. The system friction and drag differs from washer to washer. But an imbalance condition differs from load to load in a given washer. The method according to the invention is robust enough to accommodate the variations in both parts.
Looking now at FIG. 9 , the inventive method will be described in greater detail. As mentioned, a speed profile for a given washing machine is predetermined. In addition, a maximum acceptable power, P 1max , P 2max , P 3max , P 4max , is predetermined for each speed step 122 . These values are defined as the power at which the effects of imbalance for the washer are unacceptable and are determined empirically for the given model of washer. The method contemplates using two factors for ascertaining dynamic imbalance conditions: maximum power and incremental power. Moreover, it is assumed that there is an acceptable range of imbalance conditions (below Pmax) before corrective action must be taken. For imbalance conditions in an acceptable range, sampling at speed steps 1 and 2 will not trigger large effects of an unbalanced load (absent unacceptable static imbalance over Pmax). However, speed steps 3 and 4 will result in large effects. Thus, according to the method, the speed steps 3 and 4 are the steps to be carefully monitored for detecting abnormal dynamic conditions. Incremental power ΔP 3 is the power needed to increase drum rotation from speed step 2 to speed step 3 and ΔP 4 is the power needed to increase drum rotation from speed step 3 to speed step 4. Just as maximum power is determined empirically for each speed step, threshold incremental powers ΔP 3L and ΔP 4L are empirically determined for the incremental increases from speed steps 2 to 3 and 3 to 4, respectively.
As the washing machine begins its spin cycle and after the drum 102 accelerates to the first speed step, P 1 is calculated at the first sampling window. P 1 is compared to P 1max , to determine whether an unacceptable imbalance condition exists. If P 1 is not less than P 1max then the controller takes action to correct. Since at this low speed, any detected imbalance is more likely to be a static imbalance, the corrective action is most likely to be redistribution of the load (e.g., stopping the spin cycle to permit manually rearrange the clothes load, or automatically reordering the spin direction and speed.). If P 1 is less than P 1max then the controller takes the spin cycle to the next speed step 2.
Here the incremental factor begins. P 2 is calculated at the second sampling window, and P 1 and P 2 are averaged as
P _ 12 = P 1 + P 2 2
to determine an average power P 12 , which becomes a base power value for later calculations. For different system frictions, this value will be different. Meanwhile a comparison is made between P 2 and P 2max just in case an imbalance condition first appears in speed step 2. If P 2 is not less than P 2max then the control reduces the drum rotation to speed step 1, which is reprocessed. If P 2 is less than P 2max then the controller takes the spin cycle to the next speed step 3.
When the drum rotation reaches speed step 3, the effect of any dynamic imbalance may begin to appear. P 3 is calculated at the third sampling window, and the incremental power increase from step 2 to step 3 is calculated as A P 3 , using the formula ΔP 3 =P 3 − P 12 . A conventional comparison of P 3 to P 3max is made, as was done earlier for speed steps 1 and 2. In addition, the incremental power ΔP 3 is compared to the threshold incremental power for speed step 3, ΔP 3L , to ascertain whether a dynamic imbalance condition may appear at higher speeds. If ΔP 3 is less than ΔP 3L , then the controller takes the spin cycle to the next speed step 4. If, however, ΔP 3 is greater than ΔP 3L , then the drum rotation stays at speed step 3 for the remaining spin cycle. The controller may be programmed to alter the time at which the drum spins consistent with the lower rotation speed.
When the drum rotation reaches speed step 4, P 4 is calculated at the fourth sampling window, and the incremental power increase from step 3 to step 4 is calculated as ΔP 4 , using the formula ΔP 4 =P 4 − P 12 . A conventional comparison of P 4 to P 4max is made, as was done earlier for speed steps 1-3. In addition, the incremental power ΔP 4 is compared to the threshold incremental power for speed step 4, ΔP 4L , to ascertain whether a dynamic imbalance exists. If ΔP 4 is less than ΔP 4L , then the controller maintains the spin cycle at the reference speed for speed step 4. If, however, ΔP 4 is greater than ΔP 4L , then the controller will cause drum rotation to slow to speed step 3 or some other speed for the remaining spin cycle. The controller may be programmed to alter the time at which the drum spins consistent with the lower rotation speed.
FIG. 10 illustrates a sample power level plot for five different loads taken through spin cycles in a single washing machine utilizing the method according to the invention, each load represented by a separate line and separate sampling points at each speed step. In addition, the dotted boxes represent ranges of acceptable power outputs for each speed step after application of the inventive method, consistent with acceptable balance conditions at each speed step. At speed steps 1 and 2, the effect of load imbalances does not show up significantly. At speed step 3, there is a big difference between small and large imbalances, but they are still within the acceptable range. When the drum rotation reaches speed step 4, some load imbalances are within the acceptable range. However, some of the load imbalances now exceed the range, and the controller must take corrective action to reduce vibration and noise, e.g. simply reducing rotation speed to a predetermined level.
The method contemplates another speed adaptive control option called power control spinning. This option is graphically illustrated in FIG. 11 . When the rotational speed accelerates to speed step 4 from speed step 3, a large power (or torque) is needed during the dynamic period T 1 . After T 1 , the speed should reach the reference speed, if without an imbalance. When there is a large power P 4 after sampling (during T 2 ), an unacceptable imbalance condition occurs. The controller will take action. An adaptive power reference will be defined by power average P 12 and the incremental power ΔP 4L . The motor controller drives the washer to track an adapted power profile P 4ad . The drum speed is reduced to a proper speed. It is possible that a dynamic imbalance will self-correct, e.g. after water is extracted, whereupon the controller can increase speed again.
Either of these two options for adaptive speed control can limit any unexpected operation to exist in a certain limited time. For example, in extreme conditions, the steel basket 104 could be stretched to touch the tub 106 . If that were to occur, the power output will reach the maximum or ceiling value because of the large drag torque. In response, the controller can take action in N seconds to reduce the speed to a proper level. The time T max is the maximum running time when any unexpected operation could occur. Therefore, the controller can effectively monitor the washer operation status, predict and avoid performance problems before an imbalance condition causes severe degradation of performance or machine.
While any manner of detecting power output from the motor may provide useful data for the foregoing method, it is preferable to ensure stable and robust power information. FIGS. 12-14 illustrate a calibration process for removing the offset due to parameter variations in motors and controller hardware boards. A filtering process is also provided for removing bad data points in real time, based on an appropriate sampling rate range for power calculation using voltage and current measurements at the motor inverter.
Calibration
According to the invention, power P for detecting the effects of unbalance loads for the foregoing method is calculated on the basis of the DC bus voltage V bus and DC bus current I bus of the motor control inverter. A supply voltage VDD is provided for a Digital Signal Processor (DSP). The DSP preferably measures the bus voltage V bus and bus current I bus at sampling points V bus sample and I bus sample simultaneously at a sampling rate of once every 50 microseconds or 20,000 times per second (20 KHz). In general, the sampling rate can be in a range of 20 to 50 KHz. FIGS. 12 and 13 show exemplary DC bus current and DC bus voltage sensing circuits, respectively. A+15V supply voltage is provided to a single source high bandwidth operational amplifier, such as the MC34072AD, produced by Motorola. It will be apparent that the components of the sensing circuits, such as resistors R 1 -R 8 and capacitors C 1 -C 4 , may vary from one controller to another, resulting in an offset when measuring Idc from a given controller. Consequently, the power calculation of P may not be accurate from one controller to another. In practice, current offsets in measurements are unavoidable. As a result, some self calibration for cuffent offset is necessary for an accurate power calculation.
Initial offset calibration occurs by automatically detecting both V bus and I bus as soon as the controller is powered on, determining the offset, and then making an adjustment to remove the offset. Detection at the normal sampling rate of 20-50KHz occurs during initialization of the motor controller where the induction motor is not driven (PWM is shut down), and DC bus voltage is set up. At the time of initialization, measured cuffent represents the current offset. The cuffent offset is thus measured at each sample and averaged over a variable number of times, preferably 216-512 (generally enough for accuracy). Preferably, a default value is n=512. Averaging occurs as follows:
i
off
-
set
=
i
1
+
i
2
+
…
+
i
n
n
After averaging the measured current (offset current) n times, a calibration value is calculated that, if applied to a sampled current when the motor is running, will result in a zero offset. Thereafter, in the calculations of power P based on sampled current and voltage as shown in FIG. 9 , the calibration value is used to compensate for offsets. Referring now to FIG. 14 , the flow of steps in the calibration according to the invention can be seen. Upon startup 200 of the motor controller, regardless of architecture, normal initialization occurs, e.g. initializing S/W modules, timers and other system parameters ( 202 , 204 , 206 , 208 ). When the system reaches a predetermined interrupt 210 , contexts are saved and interrupt flags are cleared. Then at 212 the system queries whether or not calibration has occurred. If not, then a loop commences where PWM signals are shutdown so that the motor does not start, and current sampling commences at the predetermined sampling rate (20-50 KHz). Offset values are calculated in accord with the running average i off-set until the number of samples reaches n (preferably 216-512), at which time the calibration is complete and the flag for the query at 212 is set to true. At that point, the motor control scheme 214 will be started. It is during the motor control scheme that measurements of power P (adjusted for the offsets) in FIG. 9 occur.
Filtering
Noise is always a component of sampling signals received from the DC bus voltage and current circuits. Accuracy of power calculations can be enhanced by filtering data points affected by noise spikes. Such signals will have a sharp transition among sampling values. An adaptive moving window average filter according to the invention filters out such bad data points and is described herein.
Suppose that at any instant k, the power average of the last n (for example, 256 points) samples of a data sequence is given by:
p
k
_
=
1
n
∑
i
=
k
-
n
+
1
k
p
i
.
Similarly, at the previous time instant, k−1, the power average of the last n samples is:
p
k
-
1
_
=
1
n
∑
i
=
k
-
n
k
-
1
p
i
Therefore,
p k _ - p k - 1 _ = 1 n ( ∑ i = k - n + 1 k p i - ∑ i = k - n k - 1 p i ) = 1 n ( p k - p k - n ) ,
which can be expressed as:
p
k
_
=
p
k
-
1
_
+
1
n
(
p
k
-
p
k
-
n
)
Thus, at any instant, a moving window of n values is used to calculate the power average of the data sequence. Three values can thus be continuously calculated for the moving window: P k , P k−1 , and P k+1 . Furthermore, errors among the three power average values can be calculated compared continuously, as follows:
e k+1 = P k+1 − P k
e k = P k − P k−1
e k−1 = P k+1 − P k−1
A running comparison of errors will identify which errors are large enough to be over a pre-set limit. In such case the associated sample that resulted in the large error should be treated as a bad point and will be discarded in the sense that the sample is not used and is no longer available for further processing. Thus, higher accuracy and stability are achieved. In the illustrated embodiments, discarding a bad sample means that neither the given current and voltage samples, nor the resultant power calculation is used in the imbalance detection routine of FIG. 9 , nor is it used in the calibration method according to the invention, nor is it used further in establishing the moving window of the filtering process.
While the invention has been specifically described in connection with certain specific embodiments thereof, it is to be understood that this is by way of illustration and not of limitation, and the scope of the appended claims should be construed as broadly as the prior art will permit. | A method of determining an imbalance condition in a horizontal axis washing machine comprises several steps, including establishing a speed profile for the washing machine, having at least three increasing speed steps, operating a motor to rotate the washing machine drum sequentially through the three speed steps, measuring the power output of the motor at each speed step, calculating an average power output by averaging the power output at the first and second speed steps, calculating the difference between the power output at the third step and the average power output, comparing the difference to a predetermined threshold difference value, and sending a signal indicative of an imbalance condition if the difference exceeds the threshold difference value. | 3 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to a vapor-phase method for the synthesis of diamond films or granules possessing abrasive wear resistance, corrosionproofness, high thermal conductivity, and high specific Young's modulus and finding utility in abrasive materials, grinding materials, optical materials, super hard material tools, sliding materials, corrosionproofing materials, acoustic vibration materials, blade edge components, etc.
2. Prior Art Statement
Up to now synthesis of diamond has been carried out either by synthesis under extremely high pressure in the presence of a catalyst of iron or nickel or by direct conversion of graphite by the impact of explosion.
In the art of low-pressure CVD, recent years have seen progress in the development of a method for synthesizing diamond by imparting an excited state to a gaseous mixture of hydrogen with a hydrocarbon or an organic compound containing nitrogen, oxygen, etc. by means of a hot filament, a microwave plasma, a high-frequency plasma, a direct-current discharge plasma, or a direct-current arc discharge.
The conventional CVD method mentioned above has required a special apparatus for exciting the raw material gas to an extent sufficient for synthesis of diamond. No matter which of the aforementioned sources of excitation may be employed, it is difficult to obtain large-area diamond deposition.
OBJECT AND SUMMARY OF THE INVENTION
The inventors, after a study continued for the purpose of developing a method for vapor-phase synthesis capable of forming a diamond film of large surface area by a simple means as compared with the conventional method, found that the synthesis aimed at is accomplished by burning a raw material compound and forming an incomplete combustion region and disposing a substrate for diamond deposition in the region or in the vicinity of the region under specific conditions. This invention has been perfected as the result.
The inventors continued various studies on the low-pressure CVD method, particularly on the means of excitation, and drew the conclusion that the state of plasma such as, for example, the heat plasma with a hot filament, the microwave plasma with a microwave, or the arc discharge plasma with a direct-current arc discharge, has a significant bearing upon the synthesis of diamond. Consequently, they presumed that since the combustion flame by burning is similarly in the state of plasma, the use of the combustion flame ought to permit easy synthesis of diamond as compared with the conventional method, and pursued a study based on this theory. As a result, they perfected this invention.
To be specific, this invention is directed to a method for the vapor-phase synthesis of diamond, which is characterized by burning a raw material for deposition of diamond thereby forming a combustion flame, disposing a substrate for diamond deposition in the combustion flame, and retaining this substrate at a temperature for diamond deposition thereby causing deposition of diamond on the substrate.
The diamond synthesized by the method of this invention embraces diamond-like carbons such as i-carbon.
The above and other objects and features of the invention will become more apparent from the following detailed description with reference to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an explanatory diagram illustrating a typical apparatus for working the present invention.
FIG. 2 is a scanning electron micrograph illustrating at 3,500 magnifications a crystalline structure of the diamond film deposited in Example 1.
FIG. 3 is a scanning electron micrograph illustrating at 3,500 magnifications the crystalline structure of the diamond film deposited in Example 3.
FIG. 4 is a Raman spectrum of the diamond film deposited in Example 1.
FIG. 5 is an apparatus used for working Example 5.
FIG. 6 is an apparatus used for working Example 8.
FIG. 7 is an apparatus used for working Examples 9 and 10.
FIG. 8 is an apparatus used for working Examples 11 and 12.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The raw material gas for the synthesis of diamond will now be described below, starting with carbon sources.
(a) Hydrogen-containing compound:
Saturated hydrocarbons: Methane, ethane, propane, butane, etc.
Unsaturated hydrocarbons: Ethylene, propylene, butylene, acetylene, arylene, etc.
Aromatic hydrocarbons: Benzene, toluene, xylene, cyclohexane etc.
CHO compounds: Alcohols such as methanol, ethanol, propanol, butanol, and ether group-containing compounds.
Ketone group-containing compounds: Acetone, methyl ethyl ketone, diethyl ketone, 2,4-pentanedione, and 1'-butyronaphthone.
Esters: Methyl acetate, ethyl acetate, and isoamyl acetate.
Ketene group-containing compounds: Dimethyl ketene and phenyl ketene.
Acetyl group-containing compounds: Acetic acid, acetic anhydride, acetophenone, and biacetyl.
Aldehyde group-containing compounds: Formaldehyde, acetaldehyde, and propionaldehyde.
Methylene group-containing compounds: Ketene and diazo methane.
Methyl group-containing compounds: t-Butyl peroxide, methyl hydroperoxide, and peracetic acid.
(b) Nitrogen-containing compounds:
Primary amines: Methylamine, ethylamine, dimethylamine, trimethylamine, and isopropylamine.
Nitrile group-containing compounds: Acetonitrile, benzonitrile, acrylonitrile, and pivalonitrile.
Amide group-containing compounds: Hexaneamide and acetamide.
Nitro group-containing compounds: Nitroethane, nitromethane, nitrosobenzene, and nitropropane.
(c) Oxygen-containing compounds: Carbon monoxide.
The compounds enumerated above can be used either singly or in combinations of two or more.
Among the various compounds mentioned above, methane, ethane, propane, acetylene, ethylene, butane methyl alcohol, and ethyl alcohol prove to be used advantageously from the practical point of view.
The compound selected as a carbon source as described above, when necessary, is mixed with oxygen and further with such a non-oxidative gas such as, for example, H 2 , Ar, N 2 , Co, CO 2 , or H 2 O. The resultant gaseous mixture is burnt in an atmosphere containing or not containing oxygen.
A solid carbon or graphite may be used as a carbon source in the combustion flame of a mixed gas of the aforementioned compound with hydrogen and oxygen through such a reaction as gasification, combustion, or hydrogenation. In the above case, a non-oxidative gas may be further mixed with the aforementioned compounds.
Generally, the combustion flame comprises an incomplete combustion region, a complete combustion region, and an excess-oxygen combustion region. The method of this invention starts with the step of disposing a substrate for the deposition of diamond in the incomplete combustion region. The deposition of diamond is also obtainable by disposing the substrate in the complete combustion region. Further, the deposition of diamond is obtainable by disposing part of the substrate in the excess-oxygen region, and adjusting the temperature of the substrate, for example, by cooling with water.
The formation of an incomplete combustion region in which the raw material gas for the synthesis of diamond mixed with oxygen is excited by combustion to the state of diamond deposition either in an atmosphere containing no oxygen or in an atmosphere containing oxygen actually takes place in the form of a combustion performed in an atmosphere of argon or in the form of a combustion performed in the open air.
When acetylene, ethylene, propane, or alcohol mixed with oxygen is burned in open air to form a combustion flame, the volume of the incomplete combustion region in the combustion flame can be controlled by adjusting the amount of the oxygen mixed to the gaseous carbon source. The incomplete combustion region formed in the acetylene-oxygen flame in this case is called an "acetylene feather". The volume of this incomplete combustion region can be varied and controlled by controlling the oxygen/acetylene ratio and the total flow volume of the gases. Particularly, the oxygen/acetylene ratio can be varied in the range of 0.5 to 2, preferably 0.75 to 1.2. At this time, the temperature of the acetylene feather is no less than 2,000° C., specifically in the neighborhood of 2,500° C. No auxiliary means of excitation is required. Suitably the temperature of the substrate is in the range of 600° to 1,200° C. It can be controlled to fall in this range by cooling the substrate with water.
The synthesis of diamond may be otherwise attained by using the raw material gas for the synthesis of diamond without addition of oxygen and burning this gas in an oxygen-containing atmosphere.
FIG. 1 is an explanatory diagram illustrating a typical apparatus for carrying out the method of this invention.
In the diagram, 1 stands for a burner and 2 for a combustion flame which comprises an incomplete combustion region 3, called an inner flame, and an outer flame 4 consisting of a substantially complete combustion region and an excess-oxygen combustion region. A substrate 5 is attached to a substrate-supporting rod 6 in the illustrated embodiment. A tungsten wire filament 7 serves as an auxiliary excitation means where the combustion flame alone does not suffice for the excitation to a state suitable for the formation of diamond.
The substrate for diamond deposition denoted by 5 in the diagram may be any of the materials heretofore used for synthesis by low-pressure CVD. As concrete examples of the substrate, there may be cited shaped articles and granular articles such as Si wafer, sintered SiC article, granular SiC, W, WC, Mo, TiC, TiN, thermet, ultra-hard special tool steels, special tool steels, and high-speed steel.
In the combustion flame, the deposition of diamond takes place mainly in the oxygen-deficient region, i.e. the incomplete combustion region, generally called an inner flame and denoted by 3 in the diagram. The deposition of diamond can also be obtained in the portion of the complete combustion region close to the incomplete combustion region. Generally, the excessoxygen combustion region is extremely hot so that any diamond formed is consumed in combination with excess oxygen and is passed out in the form of CO or CO 2 . Under certain conditions, there is obtained diamond having trace etched, depending on the ratio of the amount of diamond deposited and the amount of diamond lost. The incomplete combustion region in which the deposition of diamond takes place easily is deficient in oxygen and has a relatively low temperature. In this region, the raw material gas is required to be excited to the conditions fit for the formation of hydrocarbon radicals (activated species). For the method of this invention, the substrate for diamond deposition is desired to be disposed at a portion of the flame in which the temperature is in the range of 300° to 1,400° C.
When the excitation attained in this state is not sufficient, an electric current heating, a high-frequency induction heating, a laser beam, an infrared ray, or an arc discharge may be used as an auxiliary heating source.
Specifically, the temperature of the heating region has to exceed 1,000° C., preferably 1,500° C., and the temperature of the substrate to be between 500° C. and 1,400° C., preferably between 600° C. and 1,200° C.
No auxiliary excitation means is required where the excitation is amply obtained with large energy at a high temperature as in the case of the combustion flame of a mixed gas consisting of acetylene, ethylene, propylene, alcohol, or benzene with oxygen. The deposition of diamond over a large surface area is enabled to proceed with enhanced uniformity and increased speed by superposing other excitation energy such as plasma on the combustion.
The pressure under which the flame is made to form can be selected in the range of 0.1 to 10,000 Torr, preferably 10 to 760 Torr. The synthesis under normal pressure (760 Torr) is highly advantageous from the practical point of view because it can be performed in the open air.
It is presumed that the mechanism of synthesis of diamond by the method of this invention is that the carbon-containing raw material compound in the combustion flame undergoes decomposition and dissociation through reaction with oxygen and gives rise to radical species of activation and the radical species combine as with C, C 2 , CH, CH 2 , or CH 3 and forms a diamond phase.
The reactions involved herein also form hydrogen atoms and oxygen atoms, which are believed to participate in the reaction for the deposition of diamond.
This invention permits the vapor-phase synthesis of diamond to be attained with a simple apparatus and even permits this synthesis to be carried out on a large scale suitable for commercialization. The diamond, therefore, can be produced with a homogeneous quality over a large surface area. The deposition of diamond proceeds quickly irrespective of whether the product formed is a film or granules. It is not obstructed at all when the surface of the film is curved. By the method of this invention, therefore, diamond films and granules and can be obtained easily as compared with the conventional vapor-phase method.
EXAMPLE 1
An apparatus constructed as illustrated was used. To be specific, an ordinary oxyhydrogen burner was fixed in place, a 7 mm square Si wafer substrate fastened to a SUS plate was fixed in place 7 mm above the burner nozzle, and a tungsten wire 0.3 mm in diameter was placed as an auxiliary heater 5 mm above the burner nozzle and 2 mm below the Si wafer substrate.
Hydrogen was fed to the burner at the rate of 2,000 cc/min. and methane at a rate of 50 cc/min. in the form of a mixed gas (methane/hydrogen 2.5 vol%) and burned in the open air. The tungsten wire was heated and held at 2,200° C. The temperature of the Si wafer was about 900° C.
The combustion thus produced was allowed to continue for 24 hours.
A scanning electron micrograph (3,500 magnifications) illustrating the crystalline structure of the deposit formed on the Si wafer after completion of the combustion is shown in FIG. 2.
In the diagram, a diamond film of high crystallinity abounding with diamond automorphic (111) faces is recognized. A Raman spectrum of the surface of this diamond film is illustrated in FIG. 4. This diagram shows a peak of diamond at 1,334 cm -1 and a broad low peak of i-carbon near 1,550 cm -1 . The thickness of the deposited diamond film was about 2 μm.
EXAMPLE 2
The procedure of Example 1 was repeated, except that the mixed gas fed to the burner was composed of hydrogen supplied at the rate of 2,000 cc/min., methane supplied at the rate of 50 cc/min. (2.5 vol% based on hydrogen), and oxygen supplied at the rate of 5 cc/min. (0.25 vol% based on hydrogen). When the surface of the deposit formed on the Si wafer was observed under a scanning electron microscope, the formation of a film of high crystallinity possessing the same automorphic faces of diamond as in Example 1 was confirmed. The Raman spectrum of the surface of the film was identical to that of Example 1. The diamond film thus deposited had a thickness of about 3 μm.
EXAMPLE 3
The procedure of Example 1 was repeated, except that the mixed gas fed to the burner was composed of hydrogen supplied at the rate of 2,000 cc/min. and methyl alcohol supplied at the rate of 50 cc/min. A scanning electron micrograph (3,500 magnifications) of the crystalline structure of the surface of the deposit on the Si wafer is illustrated in FIG. 3. The diagram shows the formation of a diamond film of high crystallinity abounding with automorphic (111) faces of diamond similar to those of FIG. 2. The Raman spectrum of the deposited diamond film was substantially identical to that in Example 1. The thickness of the deposited diamond was about 1 μm.
EXAMPLE 4
A mixed gas consisting of hydrogen supplied at the rate of 2,000 cc/min., methane supplied at the rate of 50 cc/min. (2.5 vol% based on hydrogen), and oxygen supplied at the rate of 200 cc/min. (10 vol% based on hydrogen) was fed to the same burner as used in Example 1 and burned to form a combustion flame in an atmosphere of argon of 100 Torr. A wafer was placed 20 mm above the burner nozzle. A tungsten wire 0.3 mm in diameter was placed as an auxiliary heater 15 mm above the burner nozzle and 5 mm below the substrate, heated, and kept at 2,200° C. The reaction was continued for 2 hours. The formation of a film possessing automorphic faces similarly to Examples 1 and 3 was recognized. In the laser Raman spectrum of the deposited film, a peak of diamond is found at 1,333 cm -1 and a weak broad peak of diamond-like carbon near 1,550 cm -1 . The thickness of the film was about 1 μm.
EXAMPLE 5
Synthesis of diamond according to the present invention was carried out by using an apparatus illustrated in FIG. 5 and using acetylene and oxygen as the raw material gas for diamond deposition. An acetylene burner 11 was fixed in place with the leading end thereof held downwardly and a Si substrate 15 having a surface area of the square of 12 mm and fixed on a water-cooled substrate supporting base 16 was placed opposite the burner nozzle. Acetylene was supplied at the rate of 1.5 liters/min. and oxygen at the rate of 1.2 liters/min. (oxygen/acetylene ratio 0.8) to the burner and burned there. Consequently, a combustion flame consisting of an incandescent core 17, an acetylene feather 13 about 60 mm in length, and an outer flame 14 was formed on the nozzle. The combustion thus produced was allowed to continue for 30 minutes. The surface of a deposit formed on the Si substrate after completion of the combustion was observed under an optical microscope. It was consequently confirmed that the entire surface of the Si substrate was covered with a film possessing automorphic diamond faces. This film was deposited on the substrate with sufficient fastness. The Raman spectrum of this diamond film was substantially identical to those of Example 1 illustrated in FIG. 4. The thickness of the diamond film was about 75 μm.
EXAMPLE 6
An acetylene-propane burner was fixed in place, with the nozzle thereof turned upwardly. A Si wafer substrate attached to a water-cooled substrate supporting base was set in place opposite the nozzle at a distance of 15 mm from the nozzle. Ethylene was supplied at the rate of 2,000 cc/min. and oxygen at 1,600 cc/min. (oxygen/ethylene ratio 0.8) to the burner and burned in the open air for 15 minutes. The deposited film on the Si wafer substrate after completion of the combustion was found by X-ray diffraction and Raman spectrometry to be a diamond deposit containing an i-carbon in a small amount. The thickness of this deposit was about 28 μm.
EXAMPLE 7
The procedure of Example 6 was repeated, except that a propane burner was used and propane was supplied at the rate of 1,800 cc/min. and oxygen at the rate of 2,000 cc/min. to the burner. The deposited film on the substrate after completion of the combustion was found to be identical in composition to that of Example 6. The diamond thus deposited was found to be slightly better than that of Example 6 in homogeneity. The thickness of the film was about 31 μm.
EXAMPLE 8
A burner 21 constructed as illustrated in FIG. 6 was used. An ultra-hard cutter 25 attached fast as a substrate to a water-cooled supporting base 26 was set in place 10 mm above the nozzle. In this apparatus, benzene in a liquid state at normal room temperature was used as a raw material to effect synthesis of diamond according to the present invention. To be specific, benzene was placed in a liquid raw material gasifying tank 27, argon gas was introduced into the benzene through a liquid raw material gasifying inlet tube 28, and the tank 27 was heated to produce a benzene-argon gas (consisting of 600 cc of benzene and 200 cc of argon in feed rate per min.). This gas was introduced through a gasified liquid raw material tube 29 and, at the same time, oxygen (1,600 cc/min.) was introduced through a gas inlet tube 30 into the burner 21 and burned in the open air for 15 minutes. In the combustion, a combustion flame 22 comprising an inner flame 23 and an outer flame 24 was formed. The film formed on the ultra-hard cutter after completion of the combustion was found by the same analysis as in Example 6 to be a compact diamond having a crystal size of 5 to 6 μm and containing i-carbon. The thickness of this film was about 37 μm.
EXAMPLE 9
Synthesis of diamond according to this invention was carried out with an apparatus constructed as illustrated in FIG. 7. To be specific, an oxygen-acetylene burner 31 provided with an ordinary gas inlet 37 was fixed in place and a 10 mm square ultra-hard alloy substrate 35 secured on a water-cooled copper substrate supporting base 36 was fixed in place 10 mm above the burner nozzle. An additional gas nozzle 38 was disposed beside the burner nozzle. In the diagram, two such nozzles were disposed one each on the opposite sides of the burner. Optionally, a plurality of such nozzles may be disposed in such a manner as to surround the burner.
Acetylene was supplied at the rate of 2,000 cc/min. and oxygen at the rate of 1,500 cc/min. through the gas inlet 37 of the burner and steam was released through the additional gas nozzle at the rate of 3% by volume based on the oxygen to cause combustion in the open air. The substrate was kept at 1,050° C. by controlling the temperature of the supporting base with cooling water. In the combustion, a combustion flame 32 comprising an inner flame 33 and an outer flame 34 was formed.
The combustion thus produced was allowed to continue for 10 minutes. The deposit formed on the substrate after completion of the combustion was found under a scanning electron microscope to be a granular diamond (20 to 40 in particle diameter) of high crystallinity covered with automorphic diamond faces (100). The microscopic Raman analysis conducted on the diamond particles confirmed the product to be diamond of high quality showing a sharp peak of diamond at 1,334 cm -1 .
EXAMPLE 10
Synthesis of diamond according to the present invention was carried out by using an apparatus constructed as illustrated in FIG. 7. An oxygen-acetylene burner was used. A 10 mm square Si wafer substrate was placed at a distance of 30 mm from the nozzle of the burner. Acetylene was supplied at the rate of 2,000 cc/min. and oxygen at the rate of 1,800 cc/min. through the gas inlet 37 of the burner and hydrogen was released through the additional gas nozzle 38 at the rate of 15% by volume based on the oxygen to cause combustion in the open air. The temperature of the substrate was kept at 600° C.
When the deposit formed on the substrate after 15 minutes' combustion was observed under a scanning electron microscope, it was confirmed to be diamond abounding with automorphic diamond faces (111). The microscopic Raman analysis confirmed the presence of a sharp peak of diamond at 1,334 cm -1 . Thus, this product was identified to be diamond of fine quality. The thickness of the film was 20 μm.
EXAMPLE 11
Synthesis of diamond according to the present invention was carried out by using an apparatus constructed as illustrated in FIG. 8. The apparatus of FIG. 8 was substantially identical with that of FIG. 1, except that no tungsten filament was used and the burner was held in a reaction chamber 50 provided with an atmospheric gas inlet 49 and a pressure gauge 48.
The reaction chamber 50 was made of stainless steel. It had an inner volume of about 25 liters and measured about 30 cm in diameter and 35 cm in height. Inside this reaction chamber, a propane burner 41 was fixed in place and a sintered SiC substrate 45 secured on a water-cooled substrate supporting base 46 made of copper and measuring 10 mm by 10 mm by 2 mm was disposed opposite the nozzle. Argon gas was introduced through the atmospheric gas inlet 49 to form an atmosphere of argon of 900 Torr inside the reaction chamber. A mixed gas consisting of 1,600 cc of propane and 2,000 cc of oxygen as feed rate per minute (oxygen/propane ratio 1.25) was introduced into the burner and burned therein. In the combustion, a combustion flame 42 comprising an inner flame 43 and an outer flame 44 was formed. The temperature of the surface of the substrate was at 900° C. The combustion thus produced was allowed to continue for 30 minutes. After the completion of the combustion, the deposited film on the substrate was examined under a scanning electron microscope. It was found to be diamond containing automorphic diamond facets. This deposit was identified by the thin-film X-ray diffraction and the laser Raman spectroscopy to be diamond containing i-carbon. The thickness of the film was about 4 μm.
EXAMPLE 12
The procedure of Example 11 was repeated, except that an acetylene burner was used instead, the interior of the reaction chamber was composed of air at 400 Torr, and the substrate was made of a 10 mm square ultra-hard alloy fixed in place 30 mm above the nozzle. A mixed gas consisting of 2,000 cc of acetylene and 2,000 cc of oxygen (oxygen/acetylene ratio 1.0) in flow rate per minute was introduced to the burner and burned for 15 minutes. When the deposited film on the substrate after completion of the combustion was examined under an optical microscope, it was confirmed to be diamond abounding in automorphic diamond facets. By the thin-film X-ray diffraction and the laser Raman spectroscopy, the product was identified to be diamond containing i-carbon. The thickness of the film was about 12 μm. | A method for vapor-phase synthesis of diamond comprises burning a raw material compound for synthesis of diamond thereby forming a combustion flame, disposing a substrate for deposition of diamond in said combustion flame, and keeping said substrate at a prescribed temperature, thereby inducing deposition of diamond on said substrate. | 2 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a system for independently operating two driven portions by a single operating member, such as a lock-releasing portion of a trunk lid locking device and a lock-releasing portion of a fuel lid locking device in an automotive vehicle.
DESCRIPTION OF THE PRIOR ART
In the prior art system for independently operating two driven portions by a single operating member, as disclosed, for example, in Japanese Patent Publication No. 52885/1987, when an inner cable portion of a push-pull type driving cable is pushed, a stopper mounted to the inner cable is fixed by abutment against a casing of a relay section, and an outer cable portion of the driving cable is contracted by a reaction thereof, thereby operating a relay operating member in one direction to operate one of the driven portions through one of driven cables. When the inner cable portion of the driving cable is pulled, the inner cable of the other driven cable is directly pulled to operate the other driven cable.
In the above prior art system, the outer cable portion of the driving cable is connected to the relay operating member, and a hollow portion of a relatively larger diameter is provided in the relay operating member for slidably accommodating the stopper mounted on the inner cable portion of the driving cable passed through the relay operating member. For this reason, the above prior art system suffers from a disadvantage that during pushing of the inner cable portion, the inner cable portion is buckled at the hollow portion of the relay operating member and as a result, a force is not efficiently transferred to the outer cable portion of the driving cable, thereby causing an operational lag in the relay operating member.
SUMMARY OF THE INVENTION
Accordingly, it is an object of the present invention to provide a system for independently operating two driven portions by a single operating member, wherein pushing and pulling forces for the inner cable portion of the driving cable can be efficiently transferred to the two driven portions to reliably operate them independently.
To achieve the above object, according to a first aspect and feature of the present invention, there is provided a system for independently operating two driven portions by a single operating member, comprising: an operating member and a relay operating member which are interconnected through a driving cable, such that the relay operating member is operated in opposite directions C and D from a second predetermined neutral position in operative association with the operating member operated in opposite directions A and B from a first predetermined neutral position; first and second driven cables having inner cable portions slidably inserted through the relay operating member for sliding movement in the directions C and D; a first expanded terminal mounted at one end of the inner cable portion for engaging the relay operating member of the first driven cable so as to pull the inner cable portion when the relay operating member is operated in the direction C from the second neutral position; and a second expanded terminal mounted at one end of the inner cable portion of the second driven cable for engaging the operating member so as to pull the inner cable of the second driven cable when the relay operating member is operated in the direction D from the second neutral position, the other ends of the inner cable portions of the first and second driven cables being connected to first and second driven portions which are operated by pulling of the inner cable portions.
With the first feature, the relay operating member is operated in the two opposite directions C and D by pushing and pulling of the inner cable portion of the driving cable and therefore, an operating force can be efficiently transferred from the driving cable to the relay operating member. In addition, the inner cable portions of the first and second driven cables are alternately pulled by the operation of the relay operating member in the directions C and D to independently operate the first and second driven portions and therefore, the operating force of the relay operating member can be also efficiently transferred to the first and second driven cables to reliably operate them.
In addition to the above first feature, according to a second aspect and feature of the present invention, the driving cable is constructed into a push-pull type.
With the second feature, it is possible to transfer the pushing and pulling forces for the inner cable portion of the driving cable directly to the relay operating member to operate the latter without any lag.
In addition to the first feature, according to a further aspect and feature of the present invention, the system further includes a first return spring for applying a biasing force In one direction to the operating member, and a second return spring for applying a biasing force in the other direction to the relay operating member so as to apply a tension to the driving cable, the second return spring having a preset load which is set such that either one of the first and second driven portions can be operated through the relay operating member, when the driving cable is loosed by the operation of the operating member, the first return spring having a preset load which is set larger than that of the second return spring, and a neutral stopper which is mounted on a support for supporting the operating member and which carries a movable end of the first return spring at the first predetermined neutral position of the operating member.
With the further feature, a relatively inexpensive usual Bowden cable can be used as the driving cable. The operating member and relay operating member can be retained at the predetermined neutral positions by cooperation of the first and second return springs, and pushing and pulling forces of the operating member for the driving cable can be transferred to the relay operating member by cooperation with the second return spring to operate the relay operating member.
The above and other objects, features and advantages of the invention will become apparent from the following description of the preferred embodiments taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a plan view of the entire structure of an operating system according to a first embodiment of the present invention;
FIG. 2 is an exploded perspective view of an operating section shown in FIG. 1;
FIG. 3 is a plan view of the operating section with a casing lid opened;
FIG. 4 is a sectional view taken along a line 4--4 in FIG. 3;
FIG. 5 is a view taken along an arrow 5 in FIG. 3;
FIG. 6 is a sectional view taken along a line 6--6 in FIG. 3;
FIG. 7 is an exploded perspective view of a relay section shown in FIG. 1;
FIG. 8 is a longitudinal sectional side view of the relay section;
FIG. 9 is an exploded perspective view of an operating section in a second embodiment of the present invention;
FIG. 10 is an exploded perspective view of a relay section in a third embodiment of the present invention;
FIG. 11 is a perspective view of the entire structure of an operating system according to a fourth embodiment of the present invention;
FIG. 12 is a perspective view of the entire structure of an operating system according to a fifth embodiment of the present invention;
FIG. 13 is a perspective view of the entire structure of an operating system according to a sixth embodiment of the present invention;
FIG. 14 is a longitudinal sectional side view of a relay section of an operating system according to a seventh embodiment of the present invention; and
FIG. 15 is a sectional view taken along a line 15--15 in FIG. 14.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The present invention will now be described by way of preferred embodiments with .reference to the accompanying drawings.
Referring first to FIGS. 1 to 8, there is shown a first embodiment of the present invention. As shown in FIG. 1, an operating section 1 and a relay section 2 are interconnected by a push-pull type driving cable 5 having an inner cable portion of a relatively large buckling strength. The relay section 2 is connected to first and second driven portions 3 and 4 through first and second Bowden driven cables 6 and 7, respectively.
This embodiment is applied to an automotive vehicle. The operating section 1 is disposed adjacent driver's seat, so that the operating section 1 can easily he operated by a driver. The first driven portion 3 serves as a lock-releasing portion in a trunk lid locking device T, and the second driven portion 4 serves as a lock-releasing portion in a fuel lid locking device F.
As shown in FIGS. 2 to 4, the operating section 1 has a casing 8 which includes a casing body 9 of synthetic resin and front and rear lids 10f and 10r also made of synthetic resin. These lids 10f and 10r are joined to an upper surface of the casing body 9. The casing body 9 is provided at its upper surface with a first wide guide groove 11 extending in a longitudinal direction of a vehicle body, a second narrow guide groove 12 adjacent and parallel to the first guide groove 11 with a partition wall interposed therebetween, and a third narrower groove 13 coaxially extending from a rear end of the second guide groove 12. The partition wall 14 is provided with a notch 15 which interconnects the first and second guide grooves 11 and 12. A neutral positioning projection 16 is provided at a longitudinally central portion of the second guide groove 12 in such a manner to protrude from the inner wall of the groove 12 opposed to the partition wall 14.
An operating member 17 in the operating section 1 includes a knob 17a, a hook-like spring shoe 17b projectingly provided at one end of the knob 17a, and a slidable rod 17c protectingly provided on one side of the spring shoe 17b. The knob 17a is accommodated into the first guide groove 11; the spring shoe 17b is accommodated into the second guide groove 12 via the notch 15, and the slidable rod 17c is accommodated into the third guide groove 13 via the second guide groove 12. Further, a pair of front and rear return springs 18f and 18r are accommodated into the second guide groove 12 for biasing the spring shoe 17b toward a position opposed to the neutral positioning projection 16, i.e., a neutral position N 1 . The operating member 17 is operated from the neutral position N 1 in forward and rearward two directions A and B of the vehicle body.
An inwardly-directed locking collar 19 is formed at a rear open edge of the third guide groove 13. A plurality of annular grooves 21, 21 are defined in an end sleeve 20f fixedly mounted at a front end of an outer cable portion 5o of the driving cable 5. The front end of the outer cable portion 5o is fixed to the casing body 9 by engagement of one of the annular grooves 21, 21 with the locking collar 19. An expanded terminal 22f is fixedly mounted at a front end of the inner cable portion 5i of the driving cable 5 and connected to a rear end of the slidable rod 17c.
As shown in FIGS. 2 and 3, the front lid 10f is for closing an upper open surface of the second guide groove 12 and has a plurality of locking claws 23 protruding downwardly. Thus, the front lid 10f is detachably joined to the casing body 9 by resilient engagement of the plurality of locking claws 23 with a plurality of locking bores 24 in an upper surface of the casing body 9.
The other rear lid 10r is for closing an upper open surface of the third groove 13 and is detachably joined to the upper surface of the casing body 9 by a machine screw 25. A decorative lid 26 covering the machine screw 25 after threaded fitting of the machine screw 25 is integrally formed on the rear lid 10r by molding for covering the machine screw 25".
The casing 8 formed in this manner is mounted to a side sill S of the vehicle body adjacent the driver's seat. The structure of mounting of the casing 8 will be described below.
Referring to FIGS. 7 to 8, a casing of the relay section 2, i.e., a relay casing 28 includes a casing body 29 and a lid plate 30 joined to an upper surface of the casing body 29. The casing body 29 is provided with a rectangular operating chamber 31 having an opened upper surface, and a guide groove 32 extending from one longitudinal end of the operating chamber 31. A relay operating member 33 is accommodated in the casing body 29 and formed into a T-shape from a relatively long shaft portion 33a and a relatively short arm 33b integrally connected at right angles to one end of the shaft portion 33a. The shaft portion 33a is slidably fitted into the guide groove 32, and the arm 33b is accommodated in the operating chamber 31.
The casing body 29 is also provided with a first insertion hole 34 1 connected to the guide groove 32, a second insertion hole 34 2 which opens into the operating chamber 31 on the opposite side from the insertion hole 34 1 , and a third insertion hole 34 3 which opens into the operating chamber 31 at a location diagonal to the second insertion hole 34 2 . Locking collars 35 1 , 35 2 and 35 3 are formed at edges of these insertion holes, respectively.
An end sleeve 20r mounted at the rear end of the outer cable portion 5o of the driving cable 5 is locked to the locking collar 35 1 of the first insertion hole 34 1 , and an expanded terminal 22r mounted at the rear end of the inner cable portion 5i is connected to a tip end of the shaft portion 33b. When the relay operating member 33 is pulled by the inner cable portion 5i of the driving cable 5, it can be moved from a neutral position N 2 in a direction C. When relay operating member 33 is pushed by the inner cable portion 5i, it can be moved from the neutral position N 2 in a direction D opposite from the direction C.
An end sleeve 36f mounted at the front end of the outer cable portion 6o of the first driven cable 6 is locked to the locking collar 35 2 of the second insertion hole 34 2 , and the inner cable portion 6i is slidably inserted through a through-groove 40 provided at one end of the arm 33b. An expanded terminal 37 is mounted at the front end of the inner cable portion 6i and occupies a position of abutment against or in proximity to one side of the arm 33b, when the relay operating member 33 is in the predetermined neutral position N 2 .
An end sleeve 38f mounted at the front end of the outer cable portion 7o of the second driven cable 7 is looked to the locking collar 35 3 of the third insertion hole 34 3 , and the inner cable portion 7i of the second driven cable 7 is slidably inserted through a through-groove 41 which is provided at the other end of the arm 33b. An expanded terminal 39 is mounted at the front end of the inner cable portion 7i and occupies a position of abutment against or in proximity to the other side of the arm 33b, when the relay operating member 33 is in the predetermined neutral position N 2 .
The neutral position N 2 of the relay operating member 33 is adjusted by changing the position of engagement of the end sleeve 20f at the outer cable portion 5o of the driving cable 5 with the locking collar 19. For the purpose of this adjustment, the plurality of annular grooves 21 are provided in the above-described manner around the outer periphery of the end sleeve 20f (see FIG. 3).
The lid plate 30 closes the upper open surfaces of the operating chamber 31 and the guide groove 32 and has a plurality of locking claws 42 protruding downwardly from a peripheral edge thereof. The lid plate 30 is detachably joined to the casing body 29 by resilient engagement of the locking claws 42 into a plurality of locking holes 43 defined in a peripheral edge of the upper surface of the casing body 29.
Referring again to FIG. 1, an end sleeve 36r is mounted at the rear end of the outer cable portion 6o of the first driven cable 6 and fixed to a fixing bracket 44 of the trunk lid locking device T, and the rear end of the inner cable portion 6i of the first driven cable 6 is connected to the lock-releasing portion 3 of the trunk lid locking device T.
In addition, an end sleeve 38r is mounted at the rear end of the outer cable portion 7o of the second driven cable 7 and fixed to a fixing bracket 45 of the fuel lid locking device F, and the inner cable portion 7i of the second driven cable 7 is connected to the lock-releasing portion 4 of the fuel lid locking device F.
The structure of mounting of the casing 8 of the operating section 1 will be described below with reference to FIGS. 3, 5 and 6.
A pair of front and rear mounting bosses 47 are protectingly provided on one side of the casing body 9 and each have, at a base thereof, a pair of upper and lower locking grooves 47a extending in the longitudinal direction of the vehicle body. A stopper piece 49 is provided on one side of the rear lid 10r to protrude in the same direction as the mounting bosses 47.
A pair of front and rear locking holes 48 are provided in the side sill S in correspondence to the mounting bosses 47. Each of the locking holes 48 includes a front narrow portion 48a and a rear wide portion 48b and formed into a T-shape.
Thus, when the mounting bosses 47 are inserted into the corresponding locking holes 48 in a condition in which the rear lid 10r has been removed, and then, the casing body 9 is moved forwardly along an inner surface of the side sill S, upper and lower edges of the narrow portions 48a of the locking holes 48 are brought into engagement with the locking grooves 47a in the mounting bosses 47. Thereafter, the rear lid 10r is secured to the casing body 9 by the machine screw 25 and in this case, the stopper piece 49 is brought into the wide portion 48b of one of the locking holes 48 to abut against the rear end of the mounting boss 47. Thus, the stopper piece 49 inhibits the escape of the mounting boss 47 from the narrow portion 48a and hence, the mounting boss 47 is fixed to the side sill S.
The operation of this embodiment will be described below. When both of the trunk lid locking device T and the fuel lid locking device F are in their locking states, and the operating member 17 of the operating section 1 assumes the shown neutral position N 1 , the relay operating member 33 in the relay section 2 assumes the neutral position N 2 , and both of the inner cable portions 6i and 7i of the first and second driven cables 6 and 7 are in their free states. Namely, both of the expanded terminals 37 and 39 of the inner cable portions 6i and 7i are in abutment against, or opposed to the arm 33b of the relay operating member 33 at a very small distance.
If an operator grasps the knob 17a and slides the operating member 17 in the direction A against the force of the front return spring 18f in order to release the locking state of the trunk lid locking device T, the inner cable portion 5i of the driving cable 5 is pulled, thereby causing the relay operating member 33 to be slid in the direction C within the relay casing 28. During this time, the arm 33b of the relay operating member 33 is brought into engagement with the expanded terminal 37 of the inner cable portion 6i of the first driven cable 6 to pull the inner cable portion 6i and hence, the lock-releasing portion 3 of the trunk lid locking device T can be operated to release the locking state of the device T.
The arm 33b of the relay operating member 33 is moved in the direction C away from the expanded terminal 39 of the inner cable portion 7i of the second driven cable 7 and hence, the sliding groove 41 in the arm 33b is only slid relative to the inner cable portion 7i and does not operate the inner cable portion 7i. Therefore, the fuel lid locking device F is still maintained in the locking state.
If the operator releases his or her hand from the operating member 17 after opening of the trunk lid, the operating member 17 is returned to the neutral position N 1 by the spring force of the front return spring 18f and in operative association with this returning movement, the relay operating member 33 is also returned to the neutral position N 2 , thereby causing the lock-releasing portion 3 to push back the inner cable portion 6i by the spring action of a return spring contained therein. If the trunk lid is thereafter closed, the trunk lid locking device T can be automatically operated to maintain the trunk lid in its closed state.
If the operating member 17 is slid by the operator in the direction B against the force of the rear return spring 18r to release the locking state of the fuel lid locking device F, the inner cable portion 5i of the driving cable 5 is pushed to slide the relay operating member 33 in the direction D. Therefore, only the inner cable portion 7i of the second driven cable 7 is pulled in the same manner as that described above, thereby operating the lock-releasing portion 4 in the fuel lid locking device F to release the locking state of the device F. During this time, obviously, the trunk lid locking device T is still maintained in the locking state.
If the operator releases his or her hand from the operating member 17 after opening of the fuel lid, the operating member 17 is returned to the neutral position N 1 by the force of the rear return spring 18r and in operative association with this, the relay operating member 33 is also returned to the neutral position N 2 , thereby causing the lock-releasing portion 4 to push back the inner cable portion 7i by the action of the return spring contained therein. If the fuel lid is then closed, the fuel lid locking device F can be automatically operated to retain the fuel lid in its closed state.
FIG. 9 illustrates a second embodiment of the present invention, in which an operating lever 17 is used as an operating member in an operating section 1. The operating lever 17 is supported by a pivot 50 on a bracket 9a projectingly provided on a casing body 9, and a sliding rod 51 is connected to a lower end of the operating lever 17 and accommodated in the guide groove 13 in the casing body 9. The inner cable portion 5i of the driving cable 5 is connected to a tip end of the sliding rod 51. The sliding rod 51 has a spring shoe 51a at its front end. The spring shoe 51a is biased toward the neutral position N 1 by a pair of front and rear return springs 18f and 18r in the wide guide groove 12. A front lid 10f is formed into an angle shape so as to be able to cover the operating lever 17 excluding a knob 17a provided at its upper end, and is provided with a slit 52 which permits the turning movement of the operating lever 17. The remaining construction is similar to that in the previously described embodiment, and portions or components corresponding to those in the previous embodiment are designated by like reference characters in FIG. 9.
In this embodiment, the direction A is a rearward direction of the vehicle body, and the direction B is a forward direction of the vehicle body. If the operating lever 17 is turned in the direction A from the neutral position N 1 , the sliding rod 51 can be moved in a direction opposite from the direction A to pull the inner cable portion 5i of the driving cable 5. Reversely, if the operating lever 17 is turned in the direction B from the neutral position N 1 , the sliding rod 51 can be moved in a direction opposite from the direction B to push the inner cable 5i. In the operating lever 17, an operating load can be determined at any value by selecting a lever ratio between upper and lower arms bounded by the pivot 50.
FIG. 10 illustrates a third embodiment of the present invention. In a relay section 2, a relay operating member 33 is formed into an L-shape with an arm 33b protruding in one of sideways directions from one end of a shaft portion 33a. The shaft portion 33a is provided with a through-groove 40 which opens into an operating chamber 31 in the casing body 29, and a wide guide groove 53 connected to the through-groove 40. The expanded terminal 37 of the inner cable portion 6i of the first driven cable 6 inserted through the through-groove 40 is slidably accommodated in the guide groove 53. The guide groove 53 has a length which is set at a value such that when the relay operating member 33 is moved in the direction S from the neutral position N 2 , the expanded terminal 37 does not interfere with the relay operating member 33. The remaining construction is similar to that in the first embodiment and hence, portions or components corresponding to those in the first embodiment are designated by like reference characters.
In this embodiment, the relay casing 28 accommodating the relay operating member 33 can be constructed in a compact manner by shortening the arm 33b of the relay operating member 33.
FIG. 11 illustrates a fourth embodiment of the present invention. In an operating section 1, a support 55 is secured to the side sill S of the vehicle body by engagement of a locking claw 65 formed at a front end of the support 55 with a locking hole 66 on the side sill S of the vehicle body and screwing a machine screw 68 inserted through a screw bore 67 in a rear portion of the support 55 into the side sill S. An operating lever 17 as an operating member is pivotally mounted on the support 55 by a pivot 56 for rotating movement in the directions A and B from the neutral position N 1 . An operating member 17 includes a relatively long operating arm 17a extending forwardly from a base portion pivotally supported on the pivot 56, a relatively short operating arm 17b extending downwardly from the base portion, and a connection portion 17c for integrally interconnecting both the arms 17a and 17b behind the pivot 56. A coil portion 57c of a first return spring 57 formed of a torsion coil spring is wound around the pivot 56, so that a fixed end 57s of the spring 57 is locked into a locking hole 63 in the support 55, and a movable end 57m of the spring 57 is movable beyond an upper end of the connecting portion 17c to resiliently abut against an upper surface of a neutral stopper 58 integrally formed on the support 55. When the movable end 57m is in abutment against the upper surface of the neutral stopper 58, the neutral position N 1 of the operating lever 17 is defined by abutment of the upper edge of the connecting portion 17c against the movable end 57m.
The driving cable 5 comprises a usual Bowden cable. An expanded terminal 22f at the front end of the inner cable portion 5i of the driving cable 5 is connected to the operating arm 17b, and an end sleeve 20f at the front end of the outer cable portion 5o of the driving cable 5 is locked to a projection piece 19 bent sideways from a rear end of the support 55.
In a relay section 2, a relay lever 33 as a relay operating member is pivotally mounted by a pivot 61 to a relay support 59 secured in place to the vehicle body by a machine screw 60. The lever 33 is pivotable in the directions C and D from the neutral position N 2 . The relay lever 33 includes left and right arms 33 L and 33 R which extend in opposite directions from an intermediate portion supported on the pivot 61. An expanded terminal 22r at the rear end of the inner cable portion 5i is connected to a tip end of the left arm 33 L , and an end sleeve 20r at the rear end of the outer cable portion 5o is locked to a raised piece 35 1 formed at a front end of the relay support 59. The inner cable portions 6i and 7i of the first and second driven cables 6 and 7 are slidably passed through the left and right arms 33 L and 33 R of the relay lever 33, and expanded terminals 37 and 39 are fixedly mounted at front ends of the inner cable portions 6i and 7i and adapted to engage front surface of the relay lever 33, when the relay lever 33 assumes the neutral position N 2 . End sleeves 36f and 38f at the front ends of the outer cable portions 6o and 7o of the first and second driven cables 6 and 7 are locked to a pair of left and right raised pieces 35 2 and 35 3 formed at a rear end of the relay support 59, respectively.
A coil portion 62c of a second return spring 62 comprising a torsion coil spring is wound around the pivot 61, so that a fixed end 62s of the spring 62 is locked into a locking hole 64 in the relay support 59, and a movable end 62m of the spring 62 is locked to a rear edge of the right arm 33 R of the relay lever 33. Thus, the relay lever 33 is biased for turning movement in a direction to pull the inner cable portion 5i, i.e., in the direction D by the second return spring 62.
In this case, the preset load of the second return spring 62 is set at a magnitude enough to enable the inner cable portion 7i of the second driven cable 7 to be pulled through the relay lever 33, and to enable the lock-releasing portion 4 in the fuel lid locking device F to be operated. The preset load of the first return spring 57 is set at a magnitude larger than that of the second return spring 62.
The remaining construction is substantially similar to that in the first embodiment, and portions or components in FIG. 11 corresponding to those in the first embodiment are designated by like reference characters.
In a free state of the operating lever 17, the movable end 57m of the first return spring 57 is in abutment against the neutral stopper 58, and the second return spring 62 provides a tension to the inner cable portion 5i of the driving cable 5 through the relay lever 33. However, because the preset load of the second return spring 62 is smaller than that of the first return spring 57, the connecting portion 17c of the operating lever 17 is merely urged against a lower surface of the movable end 57m of the first return spring 57 which is in abutment against the neutral stopper 58. As a result, the operating lever 17 is retained at the neutral position N l , and the relay lever 33 is also in the neutral position N 2 .
If the operating lever 17 is turned in the direction A in order to operate the lock-releasing portion 4 of the trunk lid locking device F in this condition, the inner cable portion 5i of the driving cable 5 is pulled to turn the relay lever 33 in the direction C against the resilient force of the second return spring 62 to pull the inner cable portion 6i of the first driven cable 6, so that the lock-releasing portion 3 can be operated. During this time, the relay lever 33 is merely slid relative to the inner cable portion 7i of the second driven cable 7 and hence, the fuel lid locking device F can be maintained in its locking state.
If the operating lever 17 is turned in the direction B against the resilient force of the first return spring 57 in order to operate the lock-releasing portion 4 of the fuel lid locking device F, the inner cable portion 5i of the driving cable 5 is loosed, so that the relay lever 33 is turned in the direction D under the action of the preset load of the second return spring 62 to pull the inner cable portion 7i of the second driven cable 7 to operate the lock-releasing portion 4. During this time, the relay lever 33 is merely slid relative to the inner cable portion 6i of the first driven cable 6 and hence, the trunk lid locking device T can be maintained in its locking state.
In this embodiment, the usual Bowden cable suffices as the driving cable 5 without use of an expensive push-pull cable and moreover, the two used first and second return springs 57 and 62 suffice. This contributes to a simplification in structure and a reduction in cost.
FIG. 12 illustrates a fifth embodiment of the present invention. A relay lever 33 is pivotally mounted at its one end on a relay support 59 in a relay section 2 by a pivot 61 for turning movement in the directions C and D from the neutral position N 2 .
The end sleeve 20r at the rear end of the outer cable portion 5o of the driving cable 5 comprising Bowden cable is locked to a raised piece 35 1 of the relay support 59, and the expanded terminal 22r at the rear end of the inner cable portion 5i is connected to the other end, i.e., the free end of the relay lever 33.
The end sleeves 36f and 38f at the front ends of the outer cable portions 6o and 7o of the first and second driven cables 6 and 7 are locked to a raised piece 35 2 at a rear end of the relay support 59 and a raised piece 35 1 at a front end of the relay support 59, respectively, and the inner cable portions 5i and 7i of the first and second driven cables 6 and 7 are slidably passed through an intermediate portion of the relay lever 33, and expanded terminals 37 and 39 are fixedly mounted at the front ends of the inner cable portions 6i and 7i and adapted to engage a front face and an end surface of the relay lever 33, respectively, when the relay lever 33 assumes the neutral position N 2 .
A second return spring 62 is mounted to the pivot 61 for biasing the relay lever 33 for turning movement in a direction to pull the inner cable portion 5i, i.e., in the direction D.
The remaining construction is similar to that in the fourth embodiment shown in FIG. 11, wherein portions or components corresponding to those in the fourth embodiment are designated by like reference characters.
In this embodiment, the relay section 2 can be reduced in size by employing the relay lever 33 of a single arm type.
FIG. 13 illustrates a sixth embodiment of the present invention. In a relay section 2, a relay casing 28 is formed into a box-like configuration longer in the longitudinal of the vehicle body. A relay operating member 33 is slidably accommodated in the relay casing 28 for sliding movement in the forward and rearward directions C and D from the neutral position N 2 , and a second return spring 62 formed of a tension coil spring for biasing the relay operating member 33 rearwardly is connected between a rear end wall 28 2 of the relay casing 28 and the relay operating member 33.
The end sleeve 20r at the rear end of the outer cable portion 5o of the driving cable 5 is locked to a front end wall 28 1 of the relay casing 28, and the expanded terminal 22r at the rear end of the inner cable portion 5i of the driving cable 5 is connected to a raised piece 70 1 of the relay operating member 33.
The end sleeves 36f and 38f at the front ends of the outer cable portions 6o and 7o of the first and second cables 6 and 7 are looked to the rear and front end walls 28 2 and 28 1 of the relay casing 28, respectively, and the inner cable portions 6i and 7i of the first and second driven cables 6 and 7 are slidably passed through a raised piece 70 2 and the raised piece 70 1 at the rear and front ends of the relay operating member 33, respectively. Expanded terminals 37 and 39 are fixedly mounted at the front ends of the inner cable portions 6i and 7i and adapted to engage a front surface of the raised piece 70 2 at the rear end of the relay operating member 33 and a rear surface of the raised piece 70 1 at the front end of the relay operating member 33, respectively, when the relay operating member 33 assumes the neutral position N 2 .
The remaining construction is similar to that in the fourth embodiment shown in FIG. 11, wherein portions or components corresponding to those in the fourth embodiment are designated by like reference characters.
In this embodiment, a pivot 61 similar to that in the fourth embodiment is not required, which enables a simplification in structure.
FIGS. 14 and 15 illustrate a seventh embodiment of the present invention. A relay casing 28 in a relay section 2 includes a cylindrical cylinder 66 of synthetic resin having a bottom wall 66a, and a cap 67 of synthetic resin resiliently fitted over an outer periphery of an open end of the cylinder 66 to close such open end. A relay operating member 33 in the form of a piston is slidably received in the cylinder 66 for sliding movement in the opposite directions C and D from a predetermined neutral position N 2 . The end sleeve 20r at the rear end of the outer cable portion 5o of the driving cable 5 is locked to the bottom wall 66a of the cylinder 66, and the inner cable portion 5i of the driving cable 5 is passed through the relay operating member 33 and has an expanded terminal 22r engaged with the rear end thereof.
The end sleeves 36f and 38f at the front ends of the outer cable portions 6o and 7o of the first and second driven cables 6 and 7 are locked to the cap 67 and the bottom wall 66a of the cylinder 66, respectively, and the inner cable portions 6i and 7i of the first and second driven cables 6 and 7 are slidably passed through the relay operating member 33. Expanded terminals 37 and 39 are fixedly mounted at the front ends of the inner cable portions 6i and 7i and adapted to engage front and rear ends of the relay operating member 33, respectively, when the relay operating member 33 assumes the neutral position N 2 .
A second return spring 62 for biasing the relay operating member 33 in the direction D is accommodated in the cylinder 66 to surround the inner cable portions 5i and 7i of the driving cable 5 and the second driven cable 7.
The remaining construction is similar to that in the fourth embodiment shown in FIG. 11, wherein portions or components corresponding to those in the fourth embodiment are designated by like reference characters.
In this embodiment, it is possible to provide a compact relay section 2.
Although the embodiments of the present invention have been described in detail, it will be understood that the present invention is not limited to these embodiment, and various modifications may be made without departing from the spirit and scope of the invention. For example, in the first embodiment, a usual Bowden cable can be used as the driving cable, and a return spring may be provided which is capable of operating the relay operating member 33 in the direction D when the Bowden cable has been loosed. | An operating member and relay operating member are interconnected through a driving cable. Inserted through the relay operating member are an inner cable portion of a first driven cable adapted to engage the relay operating member only upon movement of the latter in one direction, and an inner cable portion of a second driven cable adapted to engage the relay operating member only upon movement of the latter in the other direction. Thus, operating forces alternately applied to the operating member in two directions are efficiently transferred individually to two driven portions through the single driving cable and the two driven cables to reliably operate the driven portions. | 5 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a garment steamer. More particularly, the present invention relates to a transportable garment steamer providing improved efficiency, effectiveness and convenience in use.
[0003] 2. Description of the Prior Art
[0004] Garment steamers for use in the home are well known. For example, U.S. Pat. No. 5,609,047, U.S. Pat. No. 5,123,266, U.S. Pat. No. 4,426,857 and EP 0 079 866 each disclose a different variation on such a device.
[0005] None of the above, provide for a garment steamer that cooperates with a variety of different attachments to create a variety of different steam or vapor emitting effects, generates/emits a concentration of ions and/or ozone, and has a variety of other advantageous features. Such features include a collapsible/telescopic hanger/rod assembly, a separable fluid container, a separable insulated hose, as well as various safety features for improving safety in use. Thus, there is a need for a portable home garment steamer having the aforementioned features to provide greater flexibility, convenience, and efficiency in use. Also, preferably the steamer has a body that is sleek, compact, lightweight, and easily transportable.
SUMMARY OF THE INVENTION
[0006] It is an object of the present invention to provide a garment steamer for use in a home.
[0007] It is another object of the present invention to provide such a garment steamer that is sleek, compact and lightweight.
[0008] It is still another object of the present invention to provide such a garment steamer that improves flexibility and efficiency in use.
[0009] It is yet another object of the present invention to provide such a garment steamer that cooperates with a variety of different attachments for producing a variety of different steam or vapor, emitting effects.
[0010] It is a further object of the present invention to provide such a garment steamer that has a selectively adjustable and collapsible telescopic hanger/rod assembly.
[0011] It is still a further object of the present invention to provide such a garment steamer that has an ion and/or ozone generating/emitting feature.
[0012] These and other objects and advantages of the present invention are achieved by a garment steamer having a housing or base, a separable fluid container in separable fluid communication with a fluid heating assembly, a fluid heating assembly, a separable hose in separable fluid communication with the fluid heating assembly as well as with a variety of attachments, an adjustable and collapsible telescopic hanger/rod assembly, and at least one ion/ozone generator/emitter assembly.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] The present invention is more fully understood by reference to the following detailed description of an illustrative embodiment in combination with the drawings identified below.
[0014] FIG. 1 is a side view of the garment steamer in accordance with an illustrative embodiment of the present invention;
[0015] FIG. 2 is a side partially sectional view of the garment steamer of FIG. 1 ;
[0016] FIG. 3 is a side view of the garment steamer of FIG. 1 , showing the fluid container separated from the base;
[0017] FIG. 4 is a side section view of an illustrative adapter-hose connection;
[0018] FIG. 5 is a first view of a collapsible hanger for cooperating with the garment steamer of FIG. 1 , showing the hanger in an extended or open position;
[0019] FIG. 6 is a second view of the collapsible hanger of FIG. 5 , showing the hanger in a collapsed or closed position;
[0020] FIG. 7 is a side view of a straightening attachment for cooperating with the garment steamer of FIG. 1 ;
[0021] FIG. 8 is a top view of the straightening attachment of FIG. 7 ;
[0022] FIG. 9 is an end view of the straightening attachment of FIG. 7 ;
[0023] FIG. 10 is a side view of a concentrating attachment for cooperating with the garment steamer of FIG. 1 ;
[0024] FIG. 11 is a top view of the concentrating attachment of FIG. 10 ;
[0025] FIG. 12 is an end view of the concentrating attachment of FIG. 10 ;
[0026] FIG. 13 is a side view of a wand attachment for cooperating with the garment steamer of FIG. 1 ;
[0027] FIG. 14 is a side view of a nozzle attachment for cooperating with the garment steamer of FIG. 1 ;
[0028] FIG. 15 is a top view of the nozzle attachment of FIG. 14 ;
[0029] FIG. 16 is an end view of the nozzle attachment of FIG. 14 ;
[0030] FIG. 17 is a side view of a brush accessory for cooperating with the nozzle attachment of FIG. 14 ;
[0031] FIG. 18 is a top view of the brush accessory of FIG. 17 ;
[0032] FIG. 19 is an end view of the brush accessory of FIG. 17 ;
[0033] FIG. 20 is a side view of a fluff accessory for cooperating with the nozzle attachment of FIG. 14 ; and
[0034] FIG. 21 is an end view of the fluff accessory of FIG. 20 .
DETAILED DESCRIPTION OF THE INVENTION
[0035] Referring to the drawings and in particular, FIGS. 1 and 2 , there is shown a garment steamer in accordance with an illustrative embodiment of the present invention generally represented by reference numeral 1 . Garment steamer 1 has a housing or base 10 , a fluid container 20 , a fluid heating assembly 30 , a hose 40 , a hanger/rod assembly 50 , and at least one ion/ozone generator/emitter assembly 70 . Preferably, garment steamer 1 cooperates with a variety of different attachments 80 to provide a variety of different steaming or vaporizing effects.
[0036] Preferably, base 10 has a wide relatively flat lower portion 12 and a tall relatively cylindrical upper portion 14 configured to distribute the weight of steamer 1 such that the center of gravity thereof is lowered closer to the ground thereby improving the overall stability of the device. Also preferably, lower portion 12 and upper portion 14 each enclose a portion of fluid heating assembly 30 .
[0037] Lower portion 12 preferably has a number of transport structures 16 mounted to a bottom surface thereof. Preferably, transport structures 16 have at least four lightweight wheels made preferably of a durable plastic material. However, transport structures 16 can be of any type known to facilitate easy transport of steamer 1 . Lower portion 12 preferably also has a cord reel (not shown) for selectively retaining or storing a power chord (not shown). Alternatively, lower portion 12 can have a cord wrap 18 that allows a user to wrap and store a power cord (also not shown). In addition, lower portion 12 preferably has a control 19 disposed thereon for controlling one or more operative functions, including powering the device. Control 19 can be of any type known and sufficient to provide the user with effective access and easy use.
[0038] Upper portion 14 preferably is centrally disposed above lower portion 12 . Upper portion 14 preferably has a recess 11 with a first connector 13 for receiving fluid container 20 and connecting fluid container 20 to fluid heating assembly 30 , a second connector 15 for connecting fluid heating assembly 30 to hose 40 , and a third connector 17 for connecting hanger/rod assembly 50 .
[0039] Referring to FIGS. 2 and 3 , fluid container 20 preferably can be removed or separated from recess 11 . Fluid container 20 preferably has a handle 22 and a cap 24 . Handle 22 preferably enables the user to easily manage or cope with fluid container 20 as he/she selectively connects and/or separates the fluid container to and from recess 11 . In the illustrative embodiment shown in FIG. 3 , cap 24 preferably is removable to allow the user to add fluid into fluid container 20 when the container is separated from recess 11 . Cap 24 preferably also has a spring valve 26 and an air vent 28 . Spring valve 26 can release when fluid container 20 has a volume of fluid therein and is placed into recess 11 such that cap 24 is in fluid communication with fluid heating assembly 30 via first connector 13 . The release of spring valve 26 allows gravity to force the fluid in fluid container 20 into fluid heating assembly 30 . Air vent 28 preferably prevents a vacuum from being created to ensure that the fluid can flow until an equilibrium point is reached with respect to the fluid position between fluid container 20 and fluid heating assembly 30 . Once the equilibrium point is reached, the fluid stops flowing.
[0040] Referring to FIG. 2 , fluid heating assembly 30 preferably is centrally disposed in base 10 and has a fluid inlet 32 located in lower portion 12 of base 10 , a boiler 34 , and a fluid outlet 36 located in upper portion 14 of base 10 . Fluid inlet 32 preferably has a first tube 33 connecting boiler 34 and first connector 13 so that the first connector is in separable or releasable fluid communication with fluid container 20 . Boiler 34 preferably is die-cast and produces steam or vapor within a relatively short period of time (i.e. about 1 to about 2 minutes). Fluid outlet 36 preferably has a second tube 37 connecting boiler 34 to second connector 15 so that the second connector is in separable or releasable fluid communication with hose 40 .
[0041] Referring to FIG. 4 , hose 40 is preferably an insulated hose that can be removably or separably connected to second connector 15 shown in FIG. 1 . Preferably hose 40 is flexible and has at least an inner tube 42 and an outer tube 44 surrounding inner tube 42 . Inner tube 42 preferably facilitates thermal retention as well as fluid flow. Inner tube 42 can also preferably be formed of any suitable material for conducting heated steam or vapor. Outer tube 44 preferably provides a layer of insulation that improves thermal efficiency and increases safety in user handling. Preferably, hose 40 has an adapter 45 at each end thereof for selectively cooperating with second connector 15 and/or the variety of different attachments 80 . Preferably, adapter 45 has a tubular hollow shaft 46 with a number of annular ribs or barbs 47 and an abutment 48 disposed thereon. Barbs 47 and abutment 48 cooperate with the ends of hose 40 and a fastener 49 to frictionally connect adapter 45 , inner tube 42 , and outer tube 44 . It is noted that various other known connector assemblies may also be employed to accomplish the purpose of securely sealing and connecting hose 40 with the variety of different attachments 80 and second connector 15 , thereby providing fluid communication between heating assembly 30 and the variety of attachments. Thus, preferably when fluid container 20 is filled with fluid and placed in recess 11 such that cap 24 engages first connector 13 , fluid can flow through fluid inlet 32 and into boiler 34 to be rapidly heated or vaporized, which vapor is conveyed through fluid outlet 36 into hose 40 and out one of the variety of attachments 80 . Accordingly, the user is able to direct, manipulate or control the intensity and/or emission of the vapor to provide a variety of different steaming or vaporizing effects.
[0042] Referring to FIGS. 5 and 6 , in one embodiment of the present invention, garment steamer 1 preferably cooperates with hanger/rod assembly 50 to support or hold garments during the steaming process. Hanger/rod assembly 50 is preferably selectively telescopically adjustable and collapsible. Preferably, assembly 50 has a rod 51 telescopically connected to base 10 and a hanger 52 , connected, preferably integrally to rod 51 to collapsibly cooperate therewith. Preferably, rod 51 is telescopically received and retained in base 10 and can have a number of locks 53 to allow the rod 51 to be securely fixed at a variety of different vertical positions. Also, rod 51 can cooperate with a hose retaining mechanism 41 for storing hose 40 when not in use. Further, rod 51 can be separably connected to base 10 and can have a selectively collapsible tripod or stand (not shown) connected or integral therewith. The collapsible stand preferably cooperates with rod 51 to allow the rod to both stand alone, separate from base 10 , and to be selectively received, supported and/or retained by the base. Thus, base 10 can serve as a holder and/or as a storage container for rod 51 when not in use.
[0043] Preferably, hanger 52 has an upper support or hub 54 , shown clearly in FIGS. 5 and 6 , having one or more hanging supports 55 . Hanger 52 also preferably has at least two arms 56 pivotally connected to hub 54 . Each arm 56 has at least one hinge 57 pivotally connecting at least two beams 58 . Further, hanger 52 preferably has a lock/release button 59 for selectively positioning and securing arms 56 in a number of different positions to accommodate different types of garments. Still further, hanger 52 has at least two ribs 60 for cooperating with a slider 61 , which is slidable along rod 51 , to facilitate accomplishing the selective positioning of arms 56 . Also, hanger 52 , in addition to being connected, and preferably integral with rod 51 , can be selectively separable therefrom. This creates a greater flexibility in use, enabling the user to separably hang or support a garment on a wall or door. Also preferably, hanger 52 can be slidable along rod 51 such that the hanger can be selectively and securely positioned at any point along the rod.
[0044] Referring to FIG. 2 , in another embodiment of the present invention, garment steamer 1 preferably cooperates with an ion and/or ozone assembly 70 to infuse a garment with odor-neutralizing ions and/or ozone. Preferably, assembly 70 has one or more ion and/or ozone generator(s) 71 and one or more ion and/or ozone emitter(s) 72 operatively connected with the one ion and/or ozone generator(s). However, it is noted that ion and/or ozone assembly 70 can be any device or system capable of generating and/or emitting ions and/or ozone, such as for example, an ultraviolet (UV) light source (not shown). Preferably, the ion and/or ozone generator 71 and the ion and/or ozone emitter 72 can be positioned at any location in relation to garment steamer 1 , suitable to optimize the effective operation thereof. The ion and/or ozone generator 71 can be any device suitable for adjustably generating voltage outputs of varying intensity and/or polarity as well as different combinations thereof. The ion and/or ozone emitter 72 can have any configuration suitable to conform to the arrangement and operation of garment steamer 1 . For example, the ion and/or ozone emitter 72 can be a conductive needle, a conductive plate or any other like structure. Further, the ion and/or ozone emitter 72 can be formed of any material suitable to effectively emit ions and/or ozone as well as to conform to the constraints associated the arrangement and/or operation of the garment steamer 1 . Examples of materials that might be used include, for example, conductive metal, conductive polymer, carbon material, or silicon based material. It is noted that the ion and/or ozone generator 71 and the ion and/or ozone emitter 72 are preferably configured for safety, as well as protection from damage caused by extensive and prolonged use.
[0045] It is noted that the variety of different attachments 80 , which cooperate with garment steamer 1 , to provide a variety of different steaming or vaporizing effects, can preferably be of any type suitable for effective use with heated vapor. For example, these attachments 80 may be a straightening attachment, as shown in FIGS. 7 through 9 , a concentrator attachment, as shown in FIGS. 10 through 12 , a wand attachment, as shown in FIG. 13 , and a nozzle attachment, as shown in FIGS. 14 through 16 . It is further noted that each of the variety of different attachments 80 can be configured to selectively cooperate with a variety of different accessory parts. For example, a brush accessory, as shown in FIGS. 17 through 19 , or a fluff accessory, as shown in FIGS. 20 and 21 . Thus, the accessory parts provide greater flexibility and efficiency in use.
[0046] Having identified and described the preferred embodiments of the present invention, it is appreciated that details may be modified in a variety of ways and that alternative embodiments are also within the scope of the present invention. For example, it is possible to provide at least one of the variety of different attachments 80 , shown in FIGS. 7 through 16 and/or accessory parts shown in FIGS. 17 through 21 , with an ion and/or ozone generator and a corresponding ion and/or ozone emitter (not shown), having at least each of the attributes previously preferably described with respect to each. In this alternative embodiment, the ion and/or ozone emitter is preferably situated to effectively infuse or introduce ions and/or ozone into a garment. This introduction of ions and/or ozone into a garment has an odor-neutralizing effect and thus facilitates in the removal of lingering odors from various garments and fabrics. It is noted that the ion and/or ozone emitter can preferably be located in a selectively removable protective casing (not shown) thus preserving the integrity of the ion and/or ozone emitter and allowing selective access thereto, for cleaning and/or replacement thereof.
[0047] In another example, it is preferably possible to situate an ion and/or ozone generator and a corresponding ion and/or ozone emitter (not shown), having at least the attributes previously preferably described with respect to each, in base 10 proximate fluid outlet 36 . In this embodiment, the ion and/or ozone emitter is preferably situated to effectively infuse or introduce ions and/or ozone into the vaporized fluid exiting fluid outlet 36 . It is noted that infusing the vaporized fluid with ions and/or ozone can have a beneficial cleansing effect thereon to reduce the build up of dust and other debris, thereby improving efficiency and effectiveness of garment steamer 1 as well as extending the useful life thereof.
[0048] The present invention having been thus described with particular reference to the illustrated embodiments thereof, it will be obvious that various changes and modifications may be made therein without departing from the spirit of the present invention as defined herein. | There is provided a garment steamer for domestic use that cooperates with a variety of different attachments to provide a variety of different steam or vapor emitting effects. The garment steamer also has an ionic and/or ozone generating/emitting feature to facilitate neutralizing odor and removing undesirable particulate from a garment. The garment steamer may also have a hanger and rod assembly in which a collapsible hanger selectively cooperates with a telescopic rod, which is connected to a base, such that the hanger can be selectively positioned at any location along the height of the rod and/or disengaged from the rod. The garment steamer also includes a fluid heating assembly enclosed in the base, a separable fluid container in separable fluid communication with the fluid heating assembly, and a separable hose in separable fluid communication with the fluid heating assembly, as well as with the variety of different attachments. | 3 |
RELATED APPLICATIONS
[0001] The application claims the benefit of U.S. Provisional Application Ser. No. 61/359,218, filed Jun. 28, 2010, and entitled SWING ARM, TILT POSITIONABLE MOUNT FOR ELECTRONIC DISPLAY, said application being hereby fully incorporated herein by reference.
FIELD OF THE INVENTION
[0002] The present invention relates to mounts for televisions and monitors, and more specifically to mounts for televisions and monitors enabling positional adjustment of the display.
BACKGROUND OF THE INVENTION
[0003] As flat panel television and monitor technology advances, the displays become ever larger and thinner. The most desirable aesthetic for an electronic display is to be as thin as possible, and if mounted on a wall, to essentially have the appearance of a framed photograph. At the same time, it is highly desirable to be able to dynamically position the orientation of the display so as to enable the best possible viewing angle for the audience; usually perpendicular to the plane of the display screen.
[0004] Mounts have been previously developed that enable a wall mounted display to be positioned at nearly any angle or position. These prior mounts, however, generally have drawbacks. For example, a mount must be of relatively heavy construction in order to safely support a large electronic display. But, such heavy mounts generally require more than one person for installation of the mount—one to hold the mount in the desired position, and another to fasten the mount in place. This adds time, difficulty, and expense to the installation.
[0005] Another drawback of prior heavy mounts is that the size of the components dictates that the mount is relatively thicker, meaning that the display is positioned a relatively greater distance from the wall when the display is positioned as close as possible to the wall. This detracts from the desirable aesthetic mentioned above.
[0006] What is needed is a mount for flat panel displays that addresses the need in the industry for a mount that addresses the drawbacks of the prior art mounts.
SUMMARY OF THE INVENTION
[0007] Embodiments of the present invention address the needs of the industry for a flat panel display mount that enables full motion positioning of a display while maintaining a very thin profile for the mount such that the display can be positioned as closely as possible to the wall when desired. Further, the mount of embodiments of the invention is capable of being mounted to the wall by only one person working alone.
[0008] In an embodiment, a mount for an electronic display device includes a wall interface including a substantially vertically oriented column portion, an articulating arm assembly operably coupled with the column portion, and a display interface. The display interface presents a display interface surface for receiving the electronic display device and a display tilt assembly enabling selective horizontal tilting of the display interface surface relative to the wall. The display tilt assembly is operably coupled to the articulating arm assembly and includes a support interface portion defining a vertically oriented recess on a rear side thereof. The articulating arm assembly enables selective shifting of the display interface between a first position closely proximate the wall interface such that the column portion of the wall interface is received in the recess of the support interface portion, and a second position in which the display interface is spaced apart from the wall interface.
[0009] The wall interface can further include an upper mounting bracket and a lower mounting bracket spaced apart from the upper mounting bracket, the column portion extending between the upper mounting bracket and the lower mounting bracket. In an embodiment, the articulating arm assembly can include a pair of articulating arms.
[0010] In an embodiment, the display tilt assembly is selectively tiltable between a first generally upright position in which a top edge of the display interface surface is positioned rearwardly relative to a bottom edge of the display interface surface and a tilt position in which the top edge of the display interface surface is positioned forwardly relative to a bottom edge of the display interface surface. A center of mass of an electronic display received on the display mounting surface may first rise vertically, and then proceed along a substantially horizontal path relative to the ground as the display tilt assembly is shifted between the first generally upright position and the tilt position. The display tilt assembly may further include an interface body and pair of spaced apart arm assemblies operably coupling the interface body with the support interface portion. The spaced apart arm assemblies may each include a first arm pivotally coupled to a second arm, the first arm pivotally coupled to the interface body at a pivot, the pivot being vertically shiftable to enable the center of mass of an electronic display received on the display mounting surface to rise vertically as the display tilt assembly is shifted between the first generally upright position and the tilt position.
[0011] In an embodiment, an electronic display system includes an electronic display device, a wall interface including a substantially vertically oriented column portion, an articulating arm assembly operably coupled with the column portion, and a display interface. The display interface presents a display interface surface receiving the electronic display device thereon and a display tilt assembly enabling selective horizontal tilting of the electronic display device relative to the wall. The display tilt assembly is operably coupled to the articulating arm assembly and includes a support interface portion defining a vertically oriented recess on a rear side thereof. The articulating arm assembly enables selective shifting of the display interface between a first position closely proximate the wall interface such that the column portion of the wall interface is received in the recess of the support interface portion, and a second position in which the display interface is spaced apart from the wall interface. The wall interface may further include an upper mounting bracket and a lower mounting bracket spaced apart from the upper mounting bracket, the column portion extending between the upper mounting bracket and the lower mounting bracket. The articulating arm assembly may include a pair of articulating arms.
[0012] In an embodiment, the display tilt assembly is selectively tiltable between a first generally upright position in which a top edge of the electronic display device is positioned rearwardly relative to a bottom edge of the electronic display device and a tilt position in which the top edge of the electronic display device is positioned forwardly relative to a bottom edge of the electronic display device. A center of mass of the electronic display device may first rise vertically, and then proceed along a substantially horizontal path relative to the ground as the display tilt assembly is shifted between the first generally upright position and the tilt position. In an embodiment, the display tilt assembly may further include an interface body and pair of spaced apart arm assemblies operably coupling the interface body with the support interface portion. The spaced apart arm assemblies can each include a first arm pivotally coupled to a second arm, the first arm pivotally coupled to the interface body at a pivot, the pivot being vertically shiftable to enable the center of mass of an electronic display received on the display mounting surface to rise vertically as the display tilt assembly is shifted between the first generally upright position and the tilt position.
[0013] In an embodiment, a mount for an electronic display device includes a wall interface including a substantially vertically oriented column portion, an articulating arm assembly operably coupled with the column portion, and a display interface. The display interface presents a display interface surface for receiving the electronic display device and has tilt means for enabling selective horizontal tilting of the display interface surface relative to the wall. The tilt means includes a support interface defining a vertically oriented recess on a rear side thereof. The articulating arm assembly enables selective shifting of the display interface between a first position closely proximate the wall interface such that the column portion of the wall interface is received in the recess of the support interface, and a second position in which the display interface is spaced apart from the wall interface.
[0014] In an embodiment, the tilt means enables selective tilting between a first generally upright position in which a top edge of the display interface surface is positioned rearwardly relative to a bottom edge of the display interface surface and a tilt position in which the top edge of the display interface surface is positioned forwardly relative to a bottom edge of the display interface surface. A center of mass of an electronic display received on the display mounting surface may first rise vertically, and then proceed along a substantially horizontal path relative to the ground as the tilt means is shifted between the first generally upright position and the tilt position. The tilt means can include an interface body and pair of spaced apart arm assemblies operably coupling the interface body with the support interface portion. The spaced apart arm assemblies can each include a first arm pivotally coupled to a second arm, the first arm pivotally coupled to the interface body at a pivot, the pivot being vertically shiftable to enable the center of mass of an electronic display received on the display mounting surface to rise vertically as the display tilt assembly is shifted between the first generally upright position and the tilt position.
[0015] In an embodiment, a method of installing a mount for an electronic display device includes attaching a first bracket to a wall, coupling a first end of a generally vertically oriented column portion to the first bracket, coupling a second end of the column portion to a second bracket, and attaching the second bracket to the wall. The method may further include coupling an arm assembly to the column portion, and coupling a display interface assembly to the arm assembly.
[0016] In an embodiment, a mount for an electronic display device includes a first generally horizontal bracket, a second generally horizontal bracket, and a generally vertical elongate column portion extending between the first bracket and the second bracket. Each of the first and second brackets define structure for slidably receiving cooperating structure defined on opposing ends of the column portion. In an embodiment, the column portion defines structure for receiving an arm assembly, and the arm assembly receives a display interface, which may include a tilt assembly for enabling tilt adjustment of an electronic display coupled to the display interface.
BRIEF DESCRIPTION OF THE DRAWINGS
[0017] The invention may be more completely understood in consideration of the following detailed description of various embodiments of the invention in connection with the following drawings, in which:
[0018] FIG. 1 is a perspective view of a mount according to an embodiment of the invention in an extended position;
[0019] FIG. 2 is a perspective view of the mount of FIG. 1 in a folded position adjacent a wall to which the mount is attached;
[0020] FIG. 3 is a side elevation view of the mount of FIG. 1 in the folded position;
[0021] FIG. 4 is a side elevation view of the mount of FIG. 1 in the extended position;
[0022] FIG. 5 is a rear perspective view of the tilt assembly of the mount of FIG. 1 with a portion of the assembly depicted in phantom for clarity;
[0023] FIG. 5A is a rear perspective view of the tilt assembly of the mount of FIG. 1 showing the tilt assembly pivotally attached to the swing arms;
[0024] FIG. 6 is a fragmentary side cross-sectional view of the tilt assembly of the mount of FIG. 1 with a flat panel display attached, depicting the mount in a fully upright tilt position;
[0025] FIG. 7 is a fragmentary side cross-sectional view of the tilt assembly of the mount of FIG. 1 with a flat panel display attached, depicting the mount in an intermediate tilt position;
[0026] FIG. 8 is a fragmentary side cross-sectional view of the tilt assembly of the mount of FIG. 1 with a flat panel display attached, depicting the mount in a fully tilted tilt position;
[0027] FIG. 9 is a perspective view of a wall bracket portion of the mount of FIG. 1 ;
[0028] FIG. 10 is a fragmentary side elevation view of the wall bracket and clamp portion of the mount of FIG. 1 ;
[0029] FIG. 11 is a fragmentary perspective view of the wall bracket and clamp portion of the mount of FIG. 1 ;
[0030] FIG. 12 is a perspective view of the mount of FIG. 1 in an intermediate stage of installation;
[0031] FIG. 13 is a perspective view of the mount of FIG. 1 in a further intermediate stage of installation;
[0032] FIG. 14 is a perspective view of the mount of FIG. 1 in a final stage of installation, with the wall bracket covers depicted in phantom for clarity;
[0033] FIG. 15 is a fragmentary view of a portion of the mount of FIG. 1 depicting an arm retention assembly; and
[0034] FIG. 16 is a fragmentary rear perspective view of a portion of the mount of FIG. 1 depicting the arm retention assembly retaining the arms in a folded position.
[0035] While the invention is amenable to various modifications and alternative forms, specifics thereof have been shown by way of example in the drawings and will be described in detail. It should be understood, however, that the intention is not to limit the invention to the particular embodiments described. On the contrary, the intention is to cover all modifications, equivalents, and alternatives.
DETAILED DESCRIPTION
[0036] Display mount 100 generally includes wall interface assembly 102 , swing arm assembly 104 , and display interface assembly 106 . Wall interface assembly 102 generally includes upper wall bracket assembly 108 , central support assembly 110 , and lower wall bracket assembly 112 . Upper wall bracket assembly 108 generally includes wall bracket 114 , clamp assembly 116 , and cover 118 .
[0037] As depicted in FIG. 9 , wall bracket 114 has back plane 120 with outwardly projecting wall 122 along one edge, and lip 123 with horizontal portion 124 and vertical portion 126 along the opposing edge. Tab 128 extends downwardly from vertical portion 126 at one end of wall bracket 114 . Back plane 120 defines a pair of keyhole apertures 130 .
[0038] As depicted in FIGS. 10 and 11 , clamp assembly 116 generally includes L-shaped outer portion 132 and clamp block 134 . L-shaped outer portion 132 is removably secured to clamp block 134 with fasteners 136 . As depicted in FIG. 10 , lip 123 of wall bracket 114 is received in L-shaped recess 138 defined between L-shaped outer portion 132 and clamp block 134 . Lower wall bracket assembly 112 is identical to upper wall bracket assembly 108 , except inverted.
[0039] Central support assembly 110 is coupled to clamp assembly 116 of each of upper wall bracket assembly 108 and lower wall bracket assembly 112 , and generally includes upper support column 136 , central support columns 138 , 140 , lower support block 142 , and arm carrier 144 . Arm carrier 144 is vertically shiftable on central support columns 138 , 140 , by turning vertical adjustment screw 146 , so that the vertical position of the swing arm assembly 104 can be adjusted within a range “Y” (depicted in FIG. 1 ) relative to upper wall bracket assembly 108 and lower wall bracket assembly 112 .
[0040] Swing arm assembly 104 generally includes a pair of articulating arms 148 , 150 . Each arm 148 , 150 , generally includes lower arm 152 and upper arm 154 , pivotally coupled together at pivot joint 156 . Inner end 158 of each lower arm 152 is pivotally coupled to arm carrier 144 . Outer end 160 of each upper arm 154 is pivotally coupled to display interface assembly 106 . These pivotal connections enable display interface assembly 106 to be selectively shifted between a wall-hugging position as depicted in FIG. 2 and an extended position where display interface assembly 106 is positioned away from the wall as depicted in FIG. 1 . In addition, when display interface assembly 106 is positioned away from the wall, display interface assembly 106 can be shifted laterally relative to wall interface assembly 102 to laterally position the electronic display attached to display interface assembly 106 . It will be appreciated that hollow wire management covers 162 can be provided on each lower arm 152 and upper arm 154 to conceal and route wires and cables extending between connections in the wall and the electronic display attached to display interface assembly 106 .
[0041] Display interface assembly 106 generally includes display interface 164 , central coupling plate 166 and display tilt assembly 168 . Display tilt assembly 168 is depicted in FIGS. 5-8 and generally includes interface body 170 , support interface 172 , a pair of first tilt arms 174 , a pair of second tilt arms 176 , and a pair of guide arms 178 . Interface body 170 includes planar portion 180 with a pair of rearwardly projecting walls 182 at each lateral edge. Each wall 182 defines a rectangular aperture 184 . Planar portion 180 defines a plurality of apertures 186 for receiving fasteners to attach planar portion 180 to central coupling plate 166 .
[0042] Support interface 172 generally includes central body portion 188 with a pair of opposing walls 190 projecting rearwardly at the top and bottom margins. Each of walls 190 defines a pair of spaced apart apertures 192 positioned such that each the apertures 192 are vertically registered. Notably walls 190 are shaped conformingly to central support assembly 110 in the space between apertures 192 , effectively defining a vertically oriented recess 190 a for receiving central support assembly 110 , so that tilt assembly 168 can be positioned as closely as possible to central support assembly 110 when the mount is placed in the folded position of FIG. 2 . Apertures 192 receive pivot pins 193 , which pivotally couple upper arms 154 to support interface 172 . Support interface 172 also includes opposing lateral flange structures 194 , each including a wall portion 196 oriented perpendicular to central body portion 188 , and a laterally projecting flange 198 extending from each wall portion 196 . Wall portion 196 defines vertically oriented slot 200 which has a slightly rearwardly inclined portion 202 at the bottom end.
[0043] Each first arm 174 is pivotally coupled to second arm 176 at pivot 203 , and defines an arcuate slot 204 centered on pivot 203 . First arm 174 is pivotally coupled to support interface 172 at pivot 206 , and pivotally coupled to interface body 170 at pivot 208 . Pivot 208 is received in rectangular aperture 184 such that pivot 208 can shift vertically. Each second arm 176 is pivotally coupled to interface body 170 at pivot 210 , and is also pivotally coupled to support interface 172 at pivot 212 . Pivot 212 is slidingly received in slot 200 , such that pivot 212 can shift vertically in the slot 200 . Guide arm 178 extends between pivot 203 and guide stud 214 which extends from second arm 176 and through arcuate slot 204 .
[0044] The tilting operation of display tilt assembly 168 is depicted in FIGS. 6-8 . As depicted in FIG. 6 , with the tilt assembly in the most upright position, top end 216 of flat panel display 218 is tipped slightly in a rearward direction toward the wall on which mount 100 is attached, thereby introducing a slight bias against forward tilting motion when in this most upright position to inhibit unintentional tilting if the mount is bumped. When a user grips the top end 216 of flat panel display 218 and pulls it away from the wall, the tilting motion is initiated. Preferably, the center of mass (C.M.) of flat panel display 218 is positioned slightly outward from planar portion 180 of interface body 170 as depicted in FIGS. 6-8 . The dimensions and geometry of the linkage formed by first arms 174 , second arms 176 interface body 170 and support interface 172 , are arranged such that as motion is initiated, center of mass C.M. proceeds along a prescribed path of travel (P), first rising a slight distance in a mostly vertical direction as motion is first initiated, and then traveling horizontally level with the ground. The slight bias against initiation of tilting motion provided by the initial rise in motion is advantageous as it tends to inhibit undesired tilting if the mount is unintentionally bumped or jarred. With center of mass C.M. traveling in a horizontal path level with the ground, flat panel display 218 will be essentially self-balancing and will maintain any desired position along the full range of tilting motion from the fully upright position of FIG. 6 to the fully tilted position of FIG. 8 .
[0045] Another advantageous feature of embodiments of mount 100 is that the mount can be easily installed by only one person. To begin the installation, wall bracket 114 is attached to the wall 220 as depicted in FIG. 9 , substantially parallel to the floor or ceiling. Wall bracket 114 may be attached by first screwing lag bolts 222 into wall 220 . Bracket 114 can then be attached by advancing the heads of lag bolts 222 through enlarged end 224 of the keyhole slots 130 , and sliding wall bracket 114 to the right to engage lag bolts 222 in narrower portion 226 of keyhole slots 130 . C-clips 228 can then be clipped around lag bolts 222 below the heads in order to prevent the heads of lag bolts 222 from being drawn back through enlarged end 224 of the keyhole slots 130 should wall bracket 114 be unintentionally shifted.
[0046] With wall bracket 114 in place, clamp assembly 116 can be loosened by loosening fasteners 136 , and then slid onto lip 123 of wall bracket 114 from the right as depicted in FIG. 12 . It will be appreciated that central support assembly 110 can be positioned at any point along the length of wall bracket 114 so as to enable positioning of mount 100 at nearly any desired position on the wall. Tab 128 provides safety by preventing central support assembly 110 from being advanced past the left end of the wall bracket 114 . Once central support assembly 110 is in the desired position, fasteners 136 can be tightened to clamp central support assembly tightly to wall bracket 114 .
[0047] With central support assembly 110 now suspended from wall bracket 114 , the wall bracket 114 of lower wall bracket assembly 112 can be advanced through the clamp assembly 116 at the lower end of central support assembly 110 as depicted in FIG. 13 . Once in the desired position, this lower wall bracket 114 can be secured to the wall with lag bolts. Upwardly projecting tab 128 prevents central support assembly from being disengaged by advancing too far to the right. Both wall brackets can then be concealed with covers 118 as depicted in FIG. 14 .
[0048] A further advantageous feature of embodiments of the invention is depicted in FIGS. 1 and 15 . In particular, the mount 100 may be provided with an arm retention assembly 240 and an adjustable arm stop 242 . Arm retention assembly 240 generally includes body portion 244 , latch members 246 , 248 , guide members 250 , and spring biasing members 252 . Guide members 250 extend laterally from body portion 244 and are received in apertures in latch members 246 , 248 . Spring biasing members 252 bias latch members 246 , 248 , outwardly away from body portion 244 . Outside ends 254 of latch members 246 , 248 , are conformingly shaped to front ends 256 of upper arms 154 .
[0049] In operation, as arms 154 are pushed toward central support assembly 110 to place mount 100 in the folded position of FIG. 2 , front ends 256 of upper arms 154 contact latch members 246 , 248 , and urge them inward against the bias of spring biasing member 252 . When the mount is fully folded, front ends 256 nestle into the conforming shape of outside ends 254 of latch members 246 , 248 , and the springs 252 urge the latch members against the arms 154 , thereby tending to retain arms 154 in position. The arms can then be deployed to the extended position by simply grasping the display and pulling outwards, thereby dislodging arms 154 from latch members 246 , 248 .
[0050] Stop 242 generally includes a rubber or other elastomeric bumper element 260 which has a threaded fastener (not depicted) extending from the back side. The threaded fastener is threaded into central support assembly 110 . By turning stop 242 to either thread into or out of central support assembly 110 , the position of the outer face of the bumper 260 can be positioned closer or further away from central support assembly 110 . In operation, the outer face of the bumper 260 contacts the inner face 262 of support interface 172 , and provides a stop to prevent the swing arms from being folded too far inwardly toward the wall.
[0051] The embodiments above are intended to be illustrative and not limiting. Additional embodiments are encompassed within the scope of the claims. Although the present invention has been described with reference to particular embodiments, those 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. For purposes of interpreting the claims for the present invention, it is expressly intended that the provisions of Section 112, sixth paragraph of 35 U.S.C. are not to be invoked unless the specific terms “means for” or “step for” are recited in a claim. | A flat panel display mount that enables full motion positioning of a display while maintaining a very thin profile for the mount such that the display can be positioned as closely as possible to the wall when desired. | 6 |
CROSS-REFERENCE TO RELATED APPLICATIONS
The present application is a continuation of U.S. patent application Ser. No. 15/008,473, filed 26 Jan. 2016, which is a continuation of U.S. patent application Ser. No. 14/829,253, filed 18 Aug. 2015, (now issued as U.S. Pat. No. 9,267,071), which is a continuation of U.S. patent application Ser. No. 14/495,454, filed 24 Sep. 2014, (now U.S. Pat. No. 9,175,209), which is a continuation of U.S. patent application Ser. No. 13/717,636, filed 17 Dec. 2012, (now issued as U.S. Pat. No. 9,359,546), which is a continuation of U.S. patent application Ser. No. 13/629,018, filed 27 Sep. 2012, (now issued as U.S. Pat. No. 8,466,093), which is a continuation of U.S. patent application Ser. No. 13/353,542, filed 19 Jan. 2012, (now issued as U.S. Pat. No. 8,278,373), which in turn is a continuation of prior U.S. application Ser. No. 13/340,080, filed Dec. 29, 2011, (now issued as U.S. Pat. No. 8,455,403), which in turn is a continuation of prior U.S. application Ser. No. 12/980,510, filed Dec. 29, 2010, (now issued as U.S. Pat. No. 8,088,718), which in turn is a division of prior U.S. application Ser. No. 12/870,076, filed 27 Aug. 2010 (now issued as U.S. Pat. No. 7,902,125), which in turn is a divisional of prior U.S. application Ser. No. 11/323,031, filed 30 Dec. 2005, (now issued as U.S. Pat. No. 7,803,740), which in turn claims priority from U.S. Provisional Application Ser. No. 60/640,965, filed 30 Dec. 2004, all of which are hereby incorporated by reference herein in their entireties.
FIELD OF THE INVENTION
The present invention relates to lightweight thermoset polymer nanocomposite particles, to processes for the manufacture of such particles, and to applications of such particles. The particles of the invention contain one or optionally more than one type of nanofiller that is intimately embedded in the polymer matrix. It is possible to use a wide range of thermoset polymers and nanofillers as the main constituents of the particles of the invention, and to produce said particles by means of a wide range of fabrication techniques. Without reducing the generality of the invention, in its currently preferred embodiments, the thermoset matrix consists of a terpolymer of styrene, ethyvinylbenzene and divinylbenzene; particulate carbon black of nanoscale dimensions is used as the nanofiller, suspension polymerization is performed in the presence of the nanofiller, and optionally post-polymerization heat treatment is performed with the particles still in the reactor fluid that remains after the suspension polymerization to further advance the curing of the matrix polymer. When executed in the manner taught by this patent, many properties of both the individual particles and packings of said particles can be improved by the practice of the invention. The particles exhibit enhanced stiffness, strength, heat resistance, and resistance to aggressive environments; as well as the improved retention of high conductivity of liquids and gases through packings of said particles in aggressive environments under high compressive loads at elevated temperatures. The thermoset polymer nanocomposite particles of the invention can be used in many applications. These applications include, but are not limited to, the construction, drilling, completion and/or fracture stimulation of oil and natural gas wells; for example, as a proppant partial monolayer, a proppant pack, an integral component of a gravel pack completion, a ball bearing, a solid lubricant, a drilling mud constituent, and/or a cement additive.
BACKGROUND
The background of the invention can be described most clearly, and hence the invention can be taught most effectively, by subdividing this section in three subsections. The first subsection will provide some general background regarding the role of crosslinked (and especially stiff and strong thermoset) particles in the field of the invention. The second subsection will describe the prior art that has been taught in the patent literature. The third subsection will provide additional relevant background information selected from the vast scientific literature on polymer and composite materials science and chemistry, to further facilitate the teaching of the invention.
A. General Background
Crosslinked polymer (and especially stiff and strong thermoset) particles are used in many applications requiring high stiffness, high mechanical strength, high temperature resistance, and/or high resistance to aggressive environments. Crosslinked polymer particles can be prepared by reacting monomers or oligomers possessing three or more reactive chemical functionalities, as well as by reacting mixtures of monomers and/or oligomers at least one ingredient of which possesses three or more reactive chemical functionalities.
The intrinsic advantages of crosslinked polymer particles over polymer particles lacking a network consisting of covalent chemical bonds in such applications become especially obvious if an acceptable level of performance must be maintained for a prolonged period (such as many years, or in some applications even several decades) under the combined effects of mechanical deformation, heat, and/or severe environmental insults. For example, many high-performance thermoplastic polymers, which have excellent mechanical properties and which are hence used successfully under a variety of conditions, are unsuitable for applications where they must maintain their good mechanical properties for many years in the presence of heat and/or chemicals, because they consist of assemblies of individual polymer chains. Over time, the deformation of such assemblies of individual polymer chains at an elevated temperature can cause unacceptable amounts of creep, and furthermore solvents and/or aggressive chemicals present in the environment can gradually diffuse into them and degrade their performance severely (and in some cases even dissolve them). By contrast, the presence of a well-formed continuous network of covalent bonds restrains the molecules, thus helping retain an acceptable level of performance under severe use conditions over a much longer time period.
Oil and natural gas well construction activities, including drilling, completion and stimulation applications (such as proppants, gravel pack components, ball bearings, solid lubricants, drilling mud constituents, and/or cement additives), require the use of particulate materials, in most instances preferably of as nearly spherical a shape as possible. These (preferably substantially spherical) particles must generally be made from materials that have excellent mechanical properties. The mechanical properties of greatest interest in most such applications are stiffness (resistance to deformation) and strength under compressive loads, combined with sufficient “toughness” to avoid the brittle fracture of the particles into small pieces commonly known as “fines”. In addition, the particles must have excellent heat resistance in order to be able to withstand the combination of high compressive load and high temperature that normally becomes increasingly more severe as one drills deeper. In other words, particles that are intended for use deeper in a well must be able to withstand not only the higher overburden load resulting from the greater depth, but also the higher temperature that accompanies that higher overburden load as a result of the nature of geothermal gradients. Finally, these materials must be able to withstand the effects of the severe environmental insults (resulting from the presence of a variety of hydrocarbon and possibly solvent molecules as well as water, at simultaneously elevated temperatures and compressive loads) that the particles will encounter deep in an oil or natural gas well. The need for relatively lightweight high performance materials for use in these particulate components in applications related to the construction, drilling, completion and/or fracture stimulation of oil and natural gas wells thus becomes obvious. Consequently, while such uses constitute only a small fraction of the applications of stiff and strong materials, they provide fertile territory for the development of new or improved materials and manufacturing processes for the fabrication of such materials.
We will focus much of the remaining discussion of the background of the invention on the use of particulate materials as proppants. One key measure of end use performance of proppants is the retention of high conductivity of liquids and gases through packings of the particles in aggressive environments under high compressive loads at elevated temperatures.
The use of stiff and strong solid proppants has a long history in the oil and natural gas industry. Throughout most of this history, particles made from polymeric materials (including crosslinked polymers) have been considered to be unsuitable for use by themselves as proppants. The reason for this prejudice is the perception that polymers are too deformable, as well as lacking in the ability to withstand the combination of elevated compressive loads, temperatures and aggressive environments that are commonly encountered in oil and natural gas wells. Consequently, work on proppant material development has focused mainly on sands, on ceramics, and on sands and ceramics coated by crosslinked polymers to improve some aspects of their performance. This situation has prevailed despite the fact that most polymers have densities that are much closer to that of water so that in particulate form they can be transported much more readily into a fracture by low-density fracturing or carrier fluids such as unviscosified water.
Nonetheless, the obvious practical advantages [see a review by Edgeman (2004)] of developing the ability to use lightweight particles that possess almost neutral buoyancy relative to water have stimulated a considerable amount of work over the years. However, as will be seen from the review of the prior art provided below, progress in this field of invention has been very slow as a result of the many technical challenges that exist to the successful development of cost-effective lightweight particles that possess sufficient stiffness, strength and heat resistance.
B. Prior Art
The prior art can be described most clearly, and hence the invention can be placed in the proper context most effectively, by subdividing this section into four subsections. The first subsection will describe prior art related to the development of “as-polymerized” thermoset polymer particles. The second subsection will describe prior art related to the development of thermoset polymer particles that are subjected to post-polymerization heat treatment. The third subsection will describe prior art related to the development of thermoset polymer composite particles where the particles are reinforced by conventional fillers. The fourth subsection will describe prior art related to the development of ceramic nanocomposite particles where a ceramic matrix is reinforced by nanofillers.
1. “As-Polymerized” Thermoset Polymer Particles
As discussed above, particles made from polymeric materials have historically been considered to be unsuitable for use by themselves as proppants. Consequently, their past uses in proppant materials have focused mainly on their placement as coatings on sands and ceramics, in order to improve some aspects of the performance of the sand and ceramic proppants.
Significant progress was made in the use of crosslinked polymeric particles themselves as constituents of proppant formulations in prior art taught by Rickards, et al. (U.S. Pat. No. 6,059,034; U.S. Pat. No. 6,330,916). However, these inventors still did not consider or describe the polymeric particles as proppants. Their invention only related to the use of the polymer particles in blends with particles of more conventional proppants such as sands or ceramics. They taught that the sand or ceramic particles are the proppant particles, and that the “deformable particulate material” consisting of polymer particles mainly serves to improve the fracture conductivity, reduce the generation of fines and/or reduce proppant flowback relative to the unblended sand or ceramic proppants. Thus while their invention differs significantly from the prior art in the sense that the polymer is used in particulate form rather than being used as a coating, it shares with the prior art the limitation that the polymer still serves merely as a modifier improving the performance of a sand or ceramic proppant rather than being considered for use as a proppant in its own right.
Bienvenu (U.S. Pat. No. 5,531,274) disclosed progress towards the development of lightweight proppants consisting of high-strength crosslinked polymeric particles for use in hydraulic fracturing applications. However, embodiments of this prior art, based on the use of styrene-divinylbenzene (S-DVB) copolymer beads manufactured by using conventional fabrication technology and purchased from a commercial supplier, failed to provide an acceptable balance of performance and price. They cost far more than the test standard (Jordan sand) while being outperformed by Jordan sand in terms of the liquid conductivity and liquid permeability characteristics of their packings measured according to the industry-standard API RP 61 testing procedure. [This procedure is described by the American Petroleum Institute in its publication titled “Recommended Practices for Evaluating Short Term Proppant Pack Conductivity” (first edition, Oct. 1, 1989).] The need to use a very large amount of an expensive crosslinker (50 to 80% by weight of DVB) in order to obtain reasonable performance (not too inferior to that of Jordan Sand) was a key factor in the higher cost that accompanied the lower performance.
The most advanced prior art in stiff and strong crosslinked polymer particle technologies for use in applications in oil and natural gas drilling was developed by Albright (U.S. Pat. No. 6,248,838) who taught the concept of a “rigid chain entanglement crosslinked polymer”. In summary, the reactive formulation and the processing conditions were modified to achieve “rapid rate polymerization”. While not improving the extent of covalent crosslinking relative to conventional isothermal polymerization, rapid rate polymerization results in the “trapping” of an unusually large number of physical entanglements in the polymer. These additional entanglements can result in a major improvement of many properties. For example, the liquid conductivities of packings of S-DVB copolymer beads with w DVB =0.2 synthesized via rapid rate polymerization are comparable to those that were found by Bienvenu (U.S. Pat. No. 5,531,274) for packings of conventionally produced S-DVB beads at the much higher DVB level of w DVB =0.5. Albright (U.S. Pat. No. 6,248,838) thus provided the key technical breakthrough that enabled the development of the first generation of crosslinked polymer beads possessing sufficiently attractive combinations of performance and price characteristics to result in their commercial use in their own right as solid polymeric proppants.
2. Heat-Treated Thermoset Polymer Particles
There is no prior art that relates to the development of heat-treated thermoset polymer particles for use in oil and natural gas well construction applications. One needs to look into another field of technology to find prior art of some relevance. Nishimori, et. al. (JP1992-22230) focused on the development of particles for use in liquid crystal display panels. They taught the use of post-polymerization heat treatment to increase the compressive elastic modulus of S-DVB particles at room temperature. They only claimed compositions polymerized from reactive monomer mixtures containing 20% or more by weight of DVB or other crosslinkable monomer(s) prior to the heat treatment. They stated explicitly that improvements obtained with lower weight fractions of the crosslinkable monomer(s) were insufficient and that hence such compositions were excluded from the scope of their patent.
3. Thermoset Polymer Composite Particles
This subsection will be easier to understand if it is further subdivided into two subsections. As was discussed above, the prior art on the use of polymers as components of proppant particles has focused mainly on the development of thermoset polymer coatings for rigid inorganic materials such as sand or ceramic particles. These types of heterogeneous (composite) particles will be discussed in the first subsection. Composite particles where the thermoset polymer plays a role that goes beyond that of a coating will be discussed in the second subsection.
a. Thermoset Polymers as Coatings
The prior art discussed in this subsection is mainly of interest for historical reasons, as examples of the evolution of the use of thermoset polymers as components in composite proppant particles.
Underdown, et al. (U.S. Pat. No. 4,443,347) and of Glaze, et al. (U.S. Pat. No. 4,664,819) taught the coating of particles such as silica sand or glass beads with a thermoset polymer (such as a phenol-formaldehyde resin) that is cured fully (in their terminology, “pre-cured”) prior to the injection of a proppant charge consisting of such particles into a well.
An interesting alternative coating technology was taught by Graham, et al. (U.S. Pat. No. 4,585,064) who developed resin-coated particles comprising a particulate substrate, a substantially cured inner resin coating, and a heat-curable outer resin coating. According to their teaching, the outer resin coating should cure, and should thus enable the particles to form a coherent mass possessing the desired level of liquid conductivity, under the temperatures and compressive loads found in subterranean formations. However, it is not difficult to anticipate the many technical difficulties that can arise in attempting to reduce such an approach reliably and consistently to practice.
b. Thermoset Polymers as Matrix Phase Containing Dispersed Finely Divided Filler Material
McDaniel, et al. (U.S. Pat. No. 6,632,527) describes composite particles made of a binder and filler; for use in subterranean formations (for example, as proppants and as gravel pack components), in water filtration, and in artificial turf for sports fields. The filler consists of finely divided mineral particles that can be of any available composition. Fibers are also used in some embodiments as optional fillers. The sizes of the filler particles are required to fall within the range of 0.5 microns to 60 microns. The proportion of filler in the composite particle is very large (60% to 90% by volume). The binder formulation is required to include at least one member of the group consisting of inorganic binder, epoxy resin, novolac resin, resole resin, polyurethane resin, alkaline phenolic resole curable with ester, melamine resin, urea-aldehyde resin, urea-phenol-aldehyde resin, furans, synthetic rubber, and/or polyester resin. The final thermoset polymer composite particles of the required size and shape are obtained by a succession of process steps such as the mixing of a binder stream with a filler particle stream, agglomerative granulation, and the curing of granulated material streams.
4. Ceramic Nanocomposite Particles
Nguyen, et al. (U.S. 20050016726) taught the development of ceramic nanocomposite particles comprising a base material (present at roughly 50% to 90% by weight) and at least one nanoparticle material (present at roughly 0.1% to 30% by weight). Optionally, a polymeric binder, an organosilane coupling agent, and/or hollow microspheres, can also be included. The base material comprises clay, bauxite, alumina, silica, or mixtures thereof. It is stated that a suitable method for forming the composite particulates from the dry ingredients is to sinter by heating at a temperature of between roughly 1000° C. and 2000° C., which is a ceramic fabrication process. Given the types of formulation ingredients used as base materials by Nguyen, et al. (U.S. 20050016726), and furthermore the fact that even if they were to incorporate a polymeric binder in an embodiment of their invention said polymeric binder would not retain its normal chemical composition and polymer chain structure when a particulate is sintered by heating it at a temperature of between 1000° C. and about 2000° C., their composite particulates consist of the nanofiller(s) dispersed in a ceramic matrix.
C. Scientific Literature
The development of thermoset polymer nanocomposites requires the consideration of a vast and multidisciplinary range of polymer and composite materials science and chemistry challenges. It is essential to convey these challenges in the context of the fundamental scientific literature.
Bicerano (2002) provides a broad overview of polymer and composite materials science that can be used as a general reference for most aspects of the following discussion. Many additional references will also be provided below, to other publications which treat specific issues in greater detail than what could be accommodated in Bicerano (2002).
1. Selected Fundamental Aspects of the Curing of Crosslinked Polymers
It is essential, first, to review some fundamental aspects of the curing of crosslinked polymers, which are applicable to such polymers regardless of their form (particulate, coating, or bulk).
The properties of crosslinked polymers prepared by standard manufacturing processes are often limited by the fact that such processes typically result in incomplete curing. For example, in an isothermal polymerization process, as the glass transition temperature (T g ) of the growing polymer network increases, it may reach the polymerization temperature while the reaction is still in progress. If this happens, then the molecular motions slow down significantly so that further curing also slows down significantly. Incomplete curing yields a polymer network that is less densely crosslinked than the theoretical limit expected from the functionalities and relative amounts of the starting reactants. For example, a mixture of monomers might contain 80% DVB by weight as a crosslinker but the final extent of crosslinking that is attained may not be much greater than what was attained with a much smaller percentage of DVB. This situation results in lower stiffness, lower strength, lower heat resistance, and lower environmental resistance than the thermoset is capable of manifesting when it is fully cured and thus maximally crosslinked.
When the results of the first scan and the second scan of S-DVB beads containing various weight fractions of DVB (w DVB ), obtained by Differential Scanning Calorimetry (DSC), as reported by Bicerano, et al. (1996) (see FIG. 1 ) are compared, it becomes clear that the low performance and high cost of the “as purchased” S-DVB beads utilized by Bienvenu (U.S. Pat. No. 5,531,274) are related to incomplete curing. This incomplete curing results in the ineffective utilization of DVB as a crosslinker and thus in the incomplete development of the crosslinked network. In summary, Bicerano, et al. (1996), showed that the T g of typical “as-polymerized” S-DVB copolymers, as measured by the first DSC scan, increased only slowly with increasing w DVB , and furthermore that the rate of further increase of T g slowed down drastically for w DVB >0.08. By contrast, in the second DSC scan (performed on S-DVB specimens whose curing had been driven much closer to completion as a result of the temperature ramp that had been applied during the first scan), T g grew much more rapidly with w DVB over the entire range of up to w DVB =0.2458 that was studied. The more extensively cured samples resulting from the thermal history imposed by the first DSC scan can, thus, be considered to provide much closer approximations to the ideal theoretical limit of a “fully cured” polymer network.
2. Effects of Heat Treatment on Key Properties of Thermoset Polymers
a. Maximum Possible Use Temperature
As was illustrated by Bicerano, et al. (1996) for S-DVB copolymers with w DVB of up to 0.2458, enhancing the state of cure of a thermoset polymer network can increase T g very significantly relative to the T g of the “as-polymerized” material. In practice, the heat distortion temperature (HDT) is used most often as a practical indicator of the softening temperature of a polymer under load. As was shown by Takemori (1979), a systematic understanding of the HDT is possible through its direct correlation with the temperature dependences of the tensile (or equivalently, compressive) and shear elastic moduli. For amorphous polymers, the precipitous decrease of these elastic moduli as T g is approached from below renders the HDT well-defined, reproducible, and predictable. HDT is thus closely related to (and usually slightly lower than) T g for amorphous polymers, so that it can be increased significantly by increasing T g significantly.
The HDT decreases gradually with increasing magnitude of the load used in its measurement. For example, for general-purpose polystyrene (which has T g =100° C.), HDT=95° C. under a load of 0.46 MPa and HDT=85° C. under a load of 1.82 MPa are typical values. However, the compressive loads deep in an oil well or natural gas well are normally far higher than the standard loads (0.46 MPa and 1.82 MPa) used in measuring the HDT. Consequently, amorphous thermoset polymer particles can be expected to begin to deform significantly at a lower temperature than the HDT of the polymer measured under the standard high load of 1.82 MPa. This deformation will cause a decrease in the conductivities of liquids and gases through the propped fracture, and hence in the loss of effectiveness as a proppant, at a somewhat lower temperature than the HDT value of the polymer measured under the standard load of 1.82 MPa.
b. Mechanical Properties
As was discussed earlier, Nishimori, et. al. (JP1992-22230) used heat treatment to increase the compressive elastic modulus of their S-DVB particles (intended for use in liquid crystal display panels) significantly at room temperature (and hence far below T g ). Deformability under a compressive load is inversely proportional to the compressive elastic modulus. It is, therefore, important to consider whether one may also anticipate major benefits from heat treatment in terms of the reduction of the deformability of thermoset polymer particles intended for oil and natural gas drilling applications, when these particles are used in subterranean environments where the temperature is far below the T g of the particles. As explained below, the enhancement of curing via post-polymerization heat treatment is generally expected to have a smaller effect on the compressive elastic modulus (and hence on the proppant performance) of thermoset polymer particles when used in oil and natural gas drilling applications at temperatures far below their T g .
Nishimori, et. al. (JP1992-22230) used very large amounts of DVB (w DVB >>0.2). By contrast, much smaller amounts of DVB (w DVB ≦0.2) must be used for economic reasons in the “lower value” oil and natural gas drilling applications. The elastic moduli of a polymer at temperatures far below T g are determined primarily by deformations that are of a rather local nature and hence on a short length scale. Some enhancement of the crosslink density via further curing (when the network junctions created by the crosslinks are far away from each other to begin with) will hence not normally have nearly as large an effect on the elastic moduli as when the network junctions are very close to each other to begin with and then are brought even closer by the enhancement of curing via heat treatment. Consequently, while the compressive elastic modulus can be expected to increase significantly upon heat treatment when w DVB is very large, any such effect will normally be less pronounced at low values of w DVB . In summary, it can thus generally be expected that the enhancement of the compressive elastic modulus at temperatures far below T g will probably be small for the types of formulations that are most likely to be used in the synthesis of thermoset polymer particles for oil and natural gas drilling applications.
3. Effects of Nanoparticle Incorporation on Key Properties of Thermoset Polymers
a. Maximum Possible Use Temperature
As was pointed out by Takemori (1979), the addition of rigid fillers has a negligible effect on the HDT of amorphous polymers. However, nanocomposite materials and technologies had not yet been developed in 1979. It is, hence, important to consider, based on the data that have been gathered and the insights that have been obtained more recently, whether nanofillers may be expected to behave in a qualitatively different manner because of their geometric characteristics.
A review article by Aharoni (1998) considered this question and showed that three criteria must be considered. Here are the most relevant excerpts from his article: “When a combination of the following three conditions is fulfilled, then the glass transition temperature . . . may be increased relative to that of the same polymer in the absence of these three conditions . . . . First, very large surface area of a rigid heterogeneous material in close contact with the amorphous phase of the polymer. Such large surface areas may be obtained by having a rigid additive material extremely finely ground, preferably to nanometer length scale. Second, strong attractive interactions should exist between the heterogeneous surfaces and the polymer. In the absence of strong attractive interactions with the heterogeneous rigid surfaces, the chain segments in the boundary layer are capable of relaxing to a state approximating the bulk polymer and the T g will be identical or very slightly higher than that of the pure bulk polymer. Third, measure of motional cooperation must exist between interchain and intrachain fragments. Unlike the effects of high modulus heterogeneous additives on the averaged modulus of the system in which they are present, the elevation of T g of the polymer matrix was repeatedly shown to require not only that the polymer itself will be a high molecular weight substance, but that the additive will be finely comminuted to generate very large polymer-heterophase interfacial surface area, and, especially important, that strong attractive interactions will exist between the polymer and the foreign additive. These interactions are generally of an ionic, hydrogen bonding, or dipolar nature and, as a rule, require that the foreign additive will have surface energy higher than or at least equal to, but never lower than, that of the amorphous polymer in which it is being incorporated.”
Almost by definition, Aharoni's first condition will be satisfied for any nanofiller that has been dispersed well in the polymer matrix. Furthermore, since a thermoset polymer contains a covalently bonded three-dimensional network structure, his third condition will also be satisfied if any thermoset polymer is used as the matrix material. However, in most systems, there will not be strong attractive interactions “generally of an ionic, hydrogen bonding, or dipolar nature” between the polymer and the nanofiller, so that the second criterion will not be satisfied. It can, therefore, be concluded that, for most combinations of polymer and nanofiller, T g will not increase significantly upon incorporation of the nanofiller so that the maximum possible use temperature will not increase significantly either. There will, however, be exceptions to this general rule. Combinations of polymer and nanofiller that manifest strong attractive interactions can be found, and for such combinations both T g and the maximum possible use temperature can increase significantly upon nanofiller incorporation.
b. Mechanical Properties
It is well-established that the incorporation of rigid fillers into a polymer matrix can produce a composite material which has significantly greater stiffness (elastic modulus) and strength (stress required to induce failure) than the base polymer. It is also well-established that rigid nanofillers can generally stiffen and strengthen a polymer matrix more effectively than conventional rigid fillers of similar composition since their geometries allow them to span (or “percolate through”) a polymer specimen at much lower volume fractions than conventional fillers. This particular advantage of nanofillers over conventional fillers is well-established and a major driving force for the vast research and development effort worldwide to develop new nanocomposite products.
FIG. 2 provides an idealized schematic illustration of the effectiveness of nanofillers in terms of their ability to “percolate through” a polymer specimen even when they are present at a low volume fraction. It is important to emphasize that FIG. 2 is of a completely generic nature. It is presented merely to facilitate the understanding of nanofiller percolation, without implying that it provides an accurate depiction of the expected behavior of any particular nanofiller in any particular polymer matrix. In practice, the techniques of electron microscopy are generally used to observe the morphologies of actual embodiments of the nanocomposite concept. Specific examples of the ability of nanofillers such as carbon black and fumed silica to “percolate” at extremely low volume fractions when dispersed in polymers are provided by Zhang, et al (2001). The vast literature and trends on the dependences of percolation thresholds and packing fractions on particle shape, aggregation, and other factors, are reviewed by Bicerano, et al. (1999).
As has also been studied extensively [for example, see Okamoto, et al. (1999)] but is less widely recognized by workers in the field, the incorporation of rigid fillers of appropriate types and dimensions in the right amount (often just a very small volume fraction) can toughen a polymer in addition to stiffening it and strengthening it. “Toughening” implies a reduction in the tendency to undergo brittle fracture. If and when it is realized for proppant particles, it is an important additional benefit since it reduces the risk of the generation of “fines” during use.
4. Technical Challenges to Nanoparticle Incorporation in Thermoset Polymers
It is important to also review the many serious technical challenges that exist to the successful incorporation of nanoparticles in thermoset polymers. Appreciation of these obstacles can help workers in the field of the invention gain a better understanding of the invention. There are three major types of potential obstacles. In general, each potential obstacle will tend to become more serious with increasing nanofiller volume fraction, so that it is usually easier to incorporate a small volume fraction of a nanofiller into a polymer than it is to incorporate a larger volume fraction. This subsection is subdivided further into the following three subsections where each type of major potential obstacle will be discussed in turn.
a. Difficulty of Dispersing Nanofiller
The most common difficulty that is encountered in preparing polymer nanocomposites involves the need to disperse the nanofiller. The specific details of the source and severity of the difficulty, and of the methods that may help overcome the difficulty, differ between types of nanofillers, polymers, and fabrication processes (for example, the “in situ” synthesis of the polymer in an aqueous or organic medium containing the nanofiller, versus the addition of the nanofiller into a molten polymer). However, some important common aspects can be identified.
Most importantly, nanofiller particles of the same kind often have strong attractive interactions with each other. As a result, they tend to “clump together”; for example, preferably into agglomerates (if the nanofiller is particulate), bundles (if the nanofiller is fibrous), or stacks (if the nanofiller is discoidal). In most systems, their attractive interactions with each other are stronger than their interactions with the molecules constituting the dispersing medium, so that their dispersion is thermodynamically disfavored and hence extremely difficult.
Even in systems where the dispersion of the nanofillers is thermodynamically favored, it is often still very difficult to achieve because of the large kinetic barriers (activation energies) that must be surmounted. Consequently, nanofillers are very rarely easy to disperse in a polymer.
b. High Dispersion Viscosity
Another difficulty with the fabrication of nanocomposites is the fact that, once the nanofiller is dispersed in the appropriate medium (for example, an aqueous or organic medium containing the nanofiller for the “in situ” synthesis of the polymer, or a molten polymer into which nanofiller is added), the viscosity of the resulting dispersion may (and often does) become very high. When this happens, it can impede the successful execution of the fabrication process steps that must follow the dispersion of the nanofiller to complete the preparation of the nanocomposite.
Dispersion rheology is a vast area of both fundamental and applied research. It dates back to the 19 th century, so that there is a vast collection of data and a good fundamental understanding of the factors controlling the viscosities of dispersions. Nonetheless, it is still at the frontiers of materials science, so that major new experimental and theoretical progress is continuing to be made. In fact, the advent of nanotechnology, and the frequent emergence of high dispersion viscosity as an obstacle to the fabrication of polymer nanocomposites, have been instrumental in advancing the state of the art in this field. Bicerano, et al. (1999) have provided a comprehensive overview which can serve as a resource for workers interested in learning more about this topic.
c. Interference with Polymerization and Network Formation
An additional potential difficulty may be encountered in systems where chemical reactions are taking place in a medium containing a nanofiller. This is the possibility that the nanofiller may have an adverse effect on the chemical reactions. As can reasonably be expected, any such adverse effects can be far more severe in systems where polymerization and network formation take place simultaneously in the presence of a nanofiller than they can in systems where preformed polymer chains are crosslinked in the presence of a nanofiller. The preparation of an S-DVB nanocomposite via suspension polymerization in a medium containing a nanofiller is an example of a process where polymerization and network formation both take place in the presence of a nanofiller. On the other hand, the vulcanization of a nanofilled rubber is a process where preformed polymer chains are crosslinked in the presence of a nanofiller.
The combined consideration of the work of Lipatov, et al. (1966, 1968), Popov, et al. (1982), and Bryk, et al. (1985, 1986, 1988) helps in providing a broad perspective into the nature of the difficulties that may arise. To summarize, the presence of a filler with a high specific surface area can disrupt both polymerization and network formation in a process such as the suspension polymerization of an S-DVB copolymer nanocomposite. These outcomes can arise from the combined effects of the adsorption of initiators on the surfaces of the nanofiller particles and the interactions of the growing polymer chains with the nanofiller surfaces. Adsorption on the nanofiller surface can affect the rate of thermal decomposition of the initiator. Interactions of the growing polymer chains with the nanofiller surfaces can result both in the reduction of the mobility of growing polymer chains and in their breakage. Very strong attractions between the initiator and the nanofiller surfaces (for example, the grafting of the initiators on the nanofiller surfaces) can potentially augment all of these detrimental effects.
Taguchi, et al. (1999) provided a fascinating example of how drastically the formulation can affect the particle morphology. They described the results obtained by adding hydrophilic fine powders [nickel (Ni) of mean particle size 0.3 microns, indium oxide (In 2 O 3 ) of mean particle size 0.03 microns, and magnetite (Fe 3 O 4 ) of mean particle size 0.1, 0.3 or 0.9 microns] to the aqueous phase during the suspension polymerization of S-DVB. These particles had such a strong affinity to the aqueous phase that they did not even go inside the S-DVB beads. Instead, they remained entirely outside the beads. Consequently, the composite particles consisted of S-DVB beads whose surfaces were uniformly covered by a coating of inorganic powder. Furthermore, these S-DVB beads rapidly became smaller with increasing amount of powder at a fixed powder particle diameter, as well as with decreasing powder particle diameter (and hence increasing number concentration of powder particles) at a given powder weight fraction.
SUMMARY OF THE INVENTION
The present invention involves a novel approach towards the practical development of stiff, strong, tough, heat resistant, and environmentally resistant ultralightweight particles, for use in the construction, drilling, completion and/or fracture stimulation of oil and natural gas wells.
The disclosure is summarized below in three key aspects: (A) Compositions of Matter (thermoset nanocomposite particles that exhibit improved properties compared with prior art), (B) Processes (methods for manufacture of said compositions of matter), and (C) Applications (utilization of said compositions of matter in the construction, drilling, completion and/or fracture stimulation of oil and natural gas wells).
The disclosure describes lightweight thermoset nanocomposite particles whose properties are improved relative to prior art. The particles targeted for development include, but are not limited to, terpolymers of styrene, ethyvinylbenzene and divinylbenzene; reinforced by particulate carbon black of nanoscale dimensions. The particles exhibit any one or any combination of the following properties: enhanced stiffness, strength, heat resistance, and/or resistance to aggressive environments; and/or improved retention of high conductivity of liquids and/or gases through packings of said particles when said packings are placed in potentially aggressive environments under high compressive loads at elevated temperatures.
The disclosure also describes processes that can be used to manufacture said particles. The fabrication processes targeted for development include, but are not limited to, suspension polymerization in the presence of nanofiller, and optionally post-polymerization heat treatment with said particles still in the reactor fluid that remains after the suspension polymerization to further advance the curing of the matrix polymer.
The disclosure finally describes the use of said particles in practical applications. The targeted applications include, but are not limited to, the construction, drilling, completion and/or fracture stimulation of oil and natural gas wells; for example, as a proppant partial monolayer, a proppant pack, an integral component of a gravel pack completion, a ball bearing, a solid lubricant, a drilling mud constituent, and/or a cement additive.
A. Compositions of Matter
The compositions of matter of the present invention are thermoset polymer nanocomposite particles where one or optionally more than one type of nanofiller is intimately embedded in a polymer matrix. Any additional formulation component(s) familiar to those skilled in the art can also be used during the preparation of said particles; such as initiators, catalysts, inhibitors, dispersants, stabilizers, rheology modifiers, buffers, antioxidants, defoamers, impact modifiers, plasticizers, pigments, flame retardants, smoke retardants, or mixtures thereof. Some of the said additional component(s) may also become either partially or completely incorporated into said particles in some embodiments of the invention. However, the two required major components of said particles are a thermoset polymer matrix and at least one nanofiller. Hence this subsection will be further subdivided into three subsections. Its first subsection will teach the volume fraction of nanofiller(s) that may be used in the particles of the invention. Its second subsection will teach the types of thermoset polymers that may be used as matrix materials. Its third subsection will teach the types of nanofillers that may be incorporated.
1. Nanofiller Volume Fraction
By definition, a nanofiller possesses at least one principal axis dimension whose length is less than 0.5 microns (500 nanometers). This geometric attribute is what differentiates a nanofiller from a finely divided conventional filler, such as the fillers taught by McDaniel, et al. (U.S. Pat. No. 6,632,527) whose characteristic lengths ranged from 0.5 microns to 60 microns.
The dispersion of a nanofiller in a polymer is generally more difficult than the dispersion of a conventional filler of similar chemical composition in the same polymer. However, if dispersed properly during composite particle fabrication, nanofillers can reinforce the matrix polymer far more efficiently than conventional fillers. Consequently, while 60% to 90% by volume of filler is claimed by McDaniel, et al. (U.S. Pat. No. 6,632,527), only 0.001% to 60% by volume of nanofiller is claimed in the present invention.
Without reducing the generality of the present invention, a nanofiller volume fraction of 0.1% to 15% is used in its currently preferred embodiments.
2. Matrix Polymers
Any rigid thermoset polymer may be used as the matrix polymer of the present invention. Rigid thermoset polymers are, in general, amorphous polymers where covalent crosslinks provide a three-dimensional network. However, unlike thermoset elastomers (often referred to as “rubbers”) which also possess a three-dimensional network of covalent crosslinks, the rigid thermosets are, by definition, “stiff”. In other words, they have high elastic moduli at “room temperature” (25° C.), and often up to much higher temperatures, because their combinations of chain segment stiffness and crosslink density result in a high glass transition temperature.
Some examples of rigid thermoset polymers that can be used as matrix materials of the invention will be provided below. It is to be understood that these examples are being provided without reducing the generality of the invention, merely to facilitate the teaching of the invention.
Rigid thermoset polymers that are often used as matrix (often referred to as “binder”) materials in composites include, but are not limited to, crosslinked epoxies, epoxy vinyl esters, polyesters, phenolics, polyurethanes, and polyureas. Rigid thermoset polymers that are used less often because of their high cost despite their exceptional performance include, but are not limited to, crosslinked polyimides. These various types of polymers can, in different embodiments of the invention, be prepared by starting either from their monomers, or from oligomers that are often referred to as “prepolymers”, or from suitable mixtures of monomers and oligomers.
Many additional types of rigid thermoset polymers can also be used as matrix materials in composites, and are all within the scope of the invention. Such polymers include, but are not limited to, various families of crosslinked copolymers prepared most often by the polymerization of vinylic monomers, of vinylidene monomers, or of mixtures thereof.
The “vinyl fragment” is commonly defined as the CH 2 ═CH— fragment. So a “vinylic monomer” is a monomer of the general structure CH 2 ═CHR where R can be any one of a vast variety of molecular fragments or atoms (other than hydrogen). When a vinylic monomer CH 2 ═CHR reacts, it is incorporated into the polymer as the —CH 2 —CHR— repeat unit. Among rigid thermosets built from vinylic monomers, the crosslinked styrenics and crosslinked acrylics are especially familiar to workers in the field. Some other familiar types of vinylic monomers (among others) include the olefins, vinyl alcohols, vinyl esters, and vinyl halides.
The “vinylidene fragment” is commonly defined as the CH 2 ═CR″— fragment. So a “vinylidene monomer” is a monomer of the general structure CH 2 ═CR′R″ where R′ and R″ can each be any one of a vast variety of molecular fragments or atoms (other than hydrogen). When a vinylidene monomer CH 2 ═CR′R″ reacts, it is incorporated into a polymer as the —CH 2 —CR′R″— repeat unit. Among rigid thermosets built from vinylidene polymers, the crosslinked alkyl acrylics [such as crosslinked poly(methyl methacrylate)] are especially familiar to workers in the field. However, vinylidene monomers similar to each type of vinyl monomer (such as the styrenics, acrylates, olefins, vinyl alcohols, vinyl esters and vinyl halides, among others) can be prepared. One example of particular interest in the context of styrenic monomers is α-methyl styrene, a vinylidene-type monomer that differs from styrene (a vinyl-type monomer) by having a methyl (—CH 3 ) group serving as the R″ fragment replacing the hydrogen atom attached to the α-carbon.
Thermosets based on vinylic monomers, on vinylidene monomers, or on mixtures thereof, are typically prepared by the reaction of a mixture containing one or more non-crosslinking (difunctional) monomer and one or more crosslinking (three or higher functional) monomers. All variations in the choices of the non-crosslinking monomer(s), the crosslinking monomers(s), and their relative amounts [subject solely to the limitation that the quantity of the crosslinking monomer(s) must not be less than 1% by weight], are within the scope of the invention.
Without reducing the generality of the invention, in its currently preferred embodiments, the thermoset matrix consists of a terpolymer of styrene (non-crosslinking), ethyvinylbenzene (also non-crosslinking), and divinylbenzene (crosslinking), with the weight fraction of divinylbenzene ranging from 3% to 35% by weight of the starting monomer mixture.
3. Nanofillers
By definition, a nanofiller possesses at least one principal axis dimension whose length is less than 0.5 microns (500 nanometers). Some nanofillers possess only one principal axis dimension whose length is less than 0.5 microns. Other nanofillers possess two principal axis dimensions whose lengths are less than 0.5 microns. Yet other nanofillers possess all three principal axis dimensions whose lengths are less than 0.5 microns. Any reinforcing material possessing one nanoscale dimension, two nanoscale dimensions, or three nanoscale dimensions, can be used as the nanofiller in embodiments of the invention. Any mixture of two or more different types of such reinforcing materials can also be used as the nanofiller in embodiments of the invention.
Some examples of nanofillers that can be incorporated into the nanocomposites of the invention will be provided below. It is to be understood that these examples are being provided without reducing the generality of the invention, merely to facilitate the teaching of the invention.
Nanoscale carbon black, fumed silica and fumed alumina, such as products of these types that are currently being manufactured by the Cabot Corporation, consist of aggregates of small primary particles. See FIG. 3 for a schematic illustration of such an aggregate, and of a larger agglomerate. The aggregates may contain many very small primary particles, often arranged in a “fractal” pattern, resulting in aggregate principal axis dimensions that are also shorter than 0.5 microns. These aggregates (and not the individual primary particles that constitute them) are, in general, the smallest units of these nanofillers that are dispersed in a polymer matrix under normal fabrication conditions. The available grades of such nanofillers include variations in specific surface area, extent of branching (structure) in the aggregates, and chemical modifications intended to facilitate dispersion in different types of media (such as aqueous or organic mixtures). Some product types of such nanofillers are also provided in “fluffy” grades of lower bulk density that are easier to disperse than the base grade but less convenient to transport and store since the same weight of material occupies more volume when it is in its fluffy form. Some products grades of such nanofillers are also provided pre-dispersed in an aqueous medium.
Carbon nanotubes, carbon nanofibers, and cellulosic nanofibers constitute three other classes of nanofillers. When separated from each other by breaking up the bundles in which they are often found and then dispersed well in a polymer, they serve as fibrous reinforcing agents. In different products grades, they may have two principal axis dimensions in the nanoscale range (below 500 nanometers), or they may have all three principal axis dimensions in the nanoscale range (if they have been prepared by a process that leads to the formation of shorter nanotubes or nanofibers). Currently, carbon nanotubes constitute the most expensive nanofillers of fibrous shape. Carbon nanotubes are available in single-wall and multi-wall versions. The single-wall versions offer the highest performance, but currently do so at a much higher cost than the multi-wall versions. Nanotubes prepared from inorganic materials (such as boron nitride) are also available.
Natural and synthetic nanoclays constitute another major class of nanofiller. Nanocor and Southern Clay Products are the two leading suppliers of nanoclays at this time. When “exfoliated” (separated from each other by breaking up the stacks in which they are normally found) and dispersed well in a polymer, the nanoclays serve as discoidal (platelet-shaped) reinforcing agents. The thickness of an individual platelet is around one nanometer (0.001 microns). The lengths in the other two principal axis dimensions are much larger. They range between 100 and 500 nanometers in many product grades, thus resulting in a platelet-shaped nanofiller that has three nanoscale dimensions. They exceed 500 nanometers, and thus result in a nanofiller that has only one nanoscale dimension, in some other grades.
Many additional types of nanofillers are also available; including, but not limited to, very finely divided grades of fly ash, the polyhedral oligomeric silsesquioxanes, and clusters of different types of metals, metal alloys, and metal oxides. Since the development of nanofillers is an area that is at the frontiers of materials research and development, the future emergence of yet additional types of nanofillers that are not currently known may also be readily anticipated.
Without reducing the generality of the invention, in its currently preferred embodiments, nanoscale carbon black grades supplied by Cabot Corporation are being used as the nanofiller.
B. Processes
In most cases, the incorporation of a nanofiller into the thermoset polymer matrix will increase the compressive elastic modulus uniformly throughout the entire use temperature range (albeit usually not by exactly the same factor at each temperature), while not increasing T g significantly. The resulting nanocomposite particles will then perform better as proppants over their entire use temperature range, but without an increase in the maximum possible use temperature itself. On the other hand, if a suitable post-polymerization process step is applied to the nanocomposite particles, in many cases the curing reaction will be driven further towards completion so that T g (and hence also the maximum possible use temperature) will increase along with the increase induced by the nanofiller in the compressive elastic modulus.
Processes that may be used to enhance the degree of curing of a thermoset polymer include, but are not limited to, heat treatment (which may be combined with stirring and/or sonication to enhance its effectiveness), electron beam irradiation, and ultraviolet irradiation. We focused mainly on the use of heat treatment in order to increase the T g of the thermoset matrix polymer, to make it possible to use nanofiller incorporation and post-polymerization heat treatment as complementary methods, to improve the performance characteristics of the particles even further by combining the anticipated main benefits of each method. FIG. 4 provides an idealized schematic illustration of the benefits of implementing these methods and concepts.
The processes that may be used for the fabrication of the thermoset nanocomposite particles of the invention have at least one, and optionally two, major step(s). The required step is the formation of said particles by means of a process that allows the intimate embedment of the nanofiller in the polymer matrix. The optional step is the use of an appropriate postcuring method to advance the curing reaction of the thermoset matrix and to thus obtain a polymer network that approaches the “fully cured” limit. Consequently, this subsection will be further subdivided into two subsections, dealing with polymerization and with postcure respectively.
1. Polymerization and Network Formation in Presence of Nanofiller
Any method for the fabrication of thermoset composite particles known to those skilled in the art may be used to prepare embodiments of the thermoset nanocomposite particles of the invention. Without reducing the generality of the invention, some such methods will be discussed below to facilitate the teaching of the invention.
The most practical methods for the formation of composites containing rigid thermoset matrix polymers involve the dispersion of the filler in a liquid (aqueous or organic) medium followed by the “in situ” formation of the crosslinked polymer network around the filler. This is in contrast with the formation of thermoplastic composites where melt blending can instead also be used to mix a filler with a fully formed molten polymer. It is also in contrast with the vulcanization of a filled rubber, where preformed polymer chains are crosslinked in the presence of a filler.
The implementation of such methods in the preparation of thermoset nanocomposite particles is usually more difficult to accomplish in practice than their implementation in the preparation of composite particles containing conventional fillers. As discussed earlier, common challenges involve difficulties in dispersing the nanofiller, high nanofiller dispersion viscosity, and possible interferences of the nanofiller with polymerization and network formation. Nonetheless, these challenges can all be surmounted by making judicious choices of the formulation ingredients and their proportions, and then also determining and using the optimum processing conditions.
McDaniel, et al. (U.S. Pat. No. 6,632,527) prepared polymer composite particles with thermoset matrix formulations. Their formulations were based on at least one member of the group consisting of inorganic binder, epoxy resin, novolac resin, resole resin, polyurethane resin, alkaline phenolic resole curable with ester, melamine resin, urea-aldehyde resin, urea-phenol-aldehyde resin, furans, synthetic rubber, and/or polyester resin. They taught the incorporation of conventional filler particles, whose sizes ranged from 0.5 microns to 60 microns, at 60% to 90% by volume. Their fabrication processes differed in details depending on the specific formulation, but in general included steps involving the mixing of a binder stream with a filler particle stream, agglomerative granulation, and the curing of a granulated material stream to obtain thermoset composite particles of the required size and shape. These processes can also be used to prepare the thermoset nanocomposite particles of the present invention, where nanofillers possessing at least one principal axis dimension shorter than 0.5 microns are used at a volume fraction that does not exceed 60% and that is far smaller than 60% in the currently preferred embodiments. The processes of McDaniel, et al. (U.S. Pat. No. 6,632,527) are, hence, incorporated herein by reference.
As was discussed earlier, many additional types of thermoset polymers can also be used as the matrix materials in composites. Examples include crosslinked polymers prepared from various styrenic, acrylic or olefinic monomers (or mixtures thereof). It is more convenient to prepare particles of such thermoset polymers (as well as of their composites and nanocomposites) by using methods that can produce said particles directly in the desired (usually substantially spherical) shape during polymerization from the starting monomers. (While it is a goal of this invention to create spherical particles, it is understood that it is exceedingly difficult as well as unnecessary to obtain perfectly spherical particles. Therefore, particles with minor deviations from a perfectly spherical shape are considered perfectly spherical for the purposes of this disclosure.) Suspension (droplet) polymerization is the most powerful method available for accomplishing this objective. Two main approaches exist to suspension polymerization. The first approach is isothermal polymerization which is the conventional approach that has been practiced for many decades. The second approach is “rapid rate polymerization” as taught by Albright (U.S. Pat. No. 6,248,838) which is incorporated herein by reference. Without reducing the generality of the invention, suspension polymerization as performed via the rapid rate polymerization approach taught by Albright (U.S. Pat. No. 6,248,838) is used in the current preferred embodiments of the invention.
2. Optional Post-Polymerization Advancement of Curing and Network Formation
As was discussed earlier and illustrated in FIG. 1 with the data of Bicerano, et al. (1996), typical processes for the synthesis of thermoset polymers may result in the formation of incompletely cured networks, and may hence produce thermosets with lower glass transition temperatures and lower maximum use temperatures than is achievable with the chosen formulation of reactants. Furthermore, difficulties related to incomplete cure may sometimes be exacerbated in thermoset nanocomposites because of the possibility of interference by the nanofiller in polymerization and network formation. Consequently, the use of an optional post-polymerization process step (or a sequence of such process steps) to advance the curing of the thermoset matrix of a particle of the invention is an aspect of the invention. Suitable methods include, but are not limited to, heat treatment (also known as “annealing”), electron beam irradiation, and ultraviolet irradiation.
Post-polymerization heat treatment is a very powerful method for improving the properties and performance of S-DVB copolymers (as well as of many other types of thermoset polymers) by helping the polymer network approach its “full cure” limit. It is, in fact, the most easily implementable method for advancing the state of cure of S-DVB copolymer particles. However, it is important to recognize that another post-polymerization method (such as electron beam irradiation or ultraviolet irradiation) may be the most readily implementable one for advancing the state of cure of some other type of thermoset polymer. The use of any suitable method for advancing the curing of the thermoset polymer that is being used as the matrix of a nanocomposite of the present invention after polymerization is within the scope of the invention.
Without reducing the generality of the invention, among the suitable methods, heat treatment is used as the optional post-polymerization method to enhance the curing of the thermoset polymer matrix in the preferred embodiments of the invention. Any desired thermal history can be optionally imposed; such as, but not limited to, isothermal annealing at a fixed temperature; nonisothermal heat exposure with either a continuous or a step function temperature ramp; or any combination of continuous temperature ramps, step function temperature ramps, and/or periods of isothermal annealing at fixed temperatures. In practice, while there is great flexibility in the choice of a thermal history, it must be selected carefully to drive the curing reaction to the maximum final extent possible without inducing unacceptable levels of thermal degradation.
Any significant increase in T g by means of improved curing will translate directly into an increase of comparable magnitude in the practical softening temperature of the polymer particles under the compressive load imposed by the subterranean environment. Consequently, a significant increase of the maximum possible use temperature of the thermoset polymer particles is the most common benefit of advancing the extent of curing by heat treatment.
A practical concern during the imposition of optional heat treatment is related to the amount of material that is being subjected to heat treatment simultaneously. For example, very small amounts of material can be heat treated uniformly and effectively in vacuum; or in any inert (non-oxidizing) gaseous medium, such as, but not limited to, a helium or nitrogen “blanket”. However, heat transfer in a gaseous medium is not nearly as effective as heat transfer in an appropriately selected liquid medium. Consequently, during the optional heat treatment of large quantities of the particles of the invention (such as, but not limited to, the output of a run of a commercial-scale batch production reactor), it is usually necessary to use a liquid medium, and furthermore also to stir the particles vigorously to ensure that the heat treatment is applied as uniformly as possible. Serious quality problems may arise if heat treatment is not applied uniformly; for example, as a result of the particles that were initially near the heat source being overexposed to heat and thus damaged, while the particles that were initially far away from the heat source are not exposed to sufficient heat and are thus not sufficiently postcured.
If a gaseous or a liquid heat treatment medium is used, said medium may contain, without limitation, one or a mixture of any number of types of constituents of different molecular structure. However, in practice, said medium must be selected carefully to ensure that its molecules will not react with the crosslinked polymer particles to a sufficient extent to cause significant oxidative and/or other types of chemical degradation. In this context, it must also be kept in mind that many types of molecules which do not react with a polymer at ambient temperature may react strongly with said polymer at elevated temperatures. The most relevant example in the present context is that oxygen itself does not react with S-DVB copolymers at room temperature, while it causes severe oxidative degradation of S-DVB copolymers at elevated temperatures where there would not be much thermal degradation in its absence.
Furthermore, in considering the choice of medium for heat treatment, it is also important to keep in mind that organic molecules can swell organic polymers, potentially causing “plasticization” and thus resulting in undesirable reductions of T g and of the maximum possible use temperature. The magnitude of any such detrimental effect increases with increasing similarity between the chemical structures of the molecules in the heat treatment medium and of the polymer chains. For example, a heat transfer fluid consisting of aromatic molecules will tend to swell a styrene-divinylbenzene copolymer particle, as well as tending to swell a nanocomposite particle containing such a copolymer as its matrix. The magnitude of this detrimental effect will increase with decreasing relative amount of the crosslinking monomer (divinylbenzene) used in the formulation. For example, a styrene-divinylbenzene copolymer prepared from a formulation containing only 3% by weight of divinylbenzene will be far more susceptible to swelling in an aromatic liquid than a copolymer prepared from a formulation containing 35% divinylbenzene.
Various means known to those skilled in the art, including but not limited to the stirring and/or the sonication of an assembly of particles being subjected to heat treatment, may also be optionally used to enhance further the effectiveness of the optional heat treatment. The rate of thermal equilibration under a given thermal gradient, possibly combined with the application of any such additional means, depends on many factors. These factors include, but are not limited to, the amount of polymer particles being heat treated simultaneously, the shapes and certain key physical and transport properties of these particles, the shape of the vessel being used for heat treatment, the medium being used for heat treatment, whether external disturbances (such as stirring and/or sonication) are being used to accelerate equilibration, and the details of the heat exposure schedule. Simulations based on the solution of the heat transfer equations may hence be used optionally to optimize the heat treatment equipment and/or the heat exposure schedule.
Without reducing the generality of the invention, in its currently preferred embodiments, the thermoset nanocomposite particles are left in the reactor fluid that remains after suspension polymerization if optional heat treatment is to be used. Said reactor fluid thus serves as the heat treatment medium; and simulations based on the solution of the heat transfer equations are used to optimize the heat exposure schedule. This embodiment of the optional heat treatment works especially well (without adverse effects such as degradation and/or swelling) in enhancing the curing of the thermoset matrix polymer in the currently preferred compositions of matter of the invention. Said preferred compositions of matter consist of terpolymers of styrene, ethylvinylbenzene and divinylbenzene. Since the reactor fluid that remains after the completion of suspension polymerization is aqueous while these terpolymers are very hydrophobic, the reactor fluid serves as an excellent heat transfer medium which does not swell the particles. The use of the reactor fluid as the medium for the optional heat treatment also has the advantage of simplicity since the particles would have needed to be removed from the reactor fluid and placed in another fluid as an extra step before heat treatment if an alternative fluid had been required.
It is, however, important to reemphasize the much broader scope of the invention and the fact that the particular currently preferred embodiments summarized above constitute just a few among the vast variety of possible qualitatively different classes of embodiments. For example, if a hydrophilic thermoset polymer particle were to be developed as an alternative preferred embodiment of the invention in future work, it would obviously not be possible to subject such an embodiment to heat treatment in an aqueous slurry, and a hydrophobic heat transfer fluid would work better for its optional heat treatment.
C. Applications
The obvious practical advantages [see a review by Edgeman (2004)] of developing the ability to use lightweight particles that possess almost neutral buoyancy relative to water have stimulated a considerable amount of work over the years. However, progress in this field of invention has been very slow as a result of the many technical challenges that exist to the successful development of cost-effective lightweight particles that possess sufficient stiffness, strength and heat resistance. The present invention has resulted in the development of such stiff, strong, tough, heat resistant, and environmentally resistant ultralightweight particles; and also of cost-effective processes for the fabrication of said particles. As a result, a broad range of potential applications can be envisioned and are being pursued for the use of the thermoset polymer nanocomposite particles of the invention in the construction, drilling, completion and/or fracture stimulation of oil and natural gas wells. Without reducing the generality of the invention, in its currently preferred embodiments, the specific applications that are already being evaluated are as a proppant partial monolayer, a proppant pack, an integral component of a gravel pack completion, a ball bearing, a solid lubricant, a drilling mud constituent, and/or a cement additive.
It is also important to note that the current selection of preferred embodiments of the invention has resulted from our focus on application opportunities in the construction, drilling, completion and/or fracture stimulation of oil and natural gas wells. Many other applications can also be envisioned for the compositions of matter that fall within the scope of thermoset nanocomposite particles of the invention. For example, one such application is described by Nishimori, et. al. (JP1992-22230), who developed heat-treated S-DVB copolymer (but not composite) particles prepared from formulations containing very high DVB weight fractions for use in liquid crystal display panels. Alternative embodiments of the thermoset copolymer nanocomposite particles of the present invention, tailored towards the performance needs of that application and benefiting from its less restrictive cost limitations, could potentially also be used in liquid crystal display panels. Considered from this perspective, it can be seen readily that the potential applications of the particles of the invention extend far beyond their uses by the oil and natural gas industry.
BRIEF DESCRIPTION OF THE DRAWINGS
The accompanying drawings, which are included to provide further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention.
FIG. 1 shows the effects of advancing the curing reaction in a series of isothermally polymerized styrene-divinylbenzene (S-DVB) copolymers containing different DVB weight fractions via heat treatment. The results of scans of S-DVB beads containing various weight fractions of DVB (w DVB ), obtained by Differential Scanning Calorimetry (DSC), and reported by Bicerano, et al. (1996), are compared. It is seen that the T g of typical “as-polymerized” S-DVB copolymers, as measured by the first DSC scan, increased only slowly with increasing w DVB , and furthermore that the rate of further increase of T g slowed down drastically for w DVB >0.08. By contrast, in the second DSC scan (performed on S-DVB specimens whose curing had been driven much closer to completion as a result of the temperature ramp that had been applied during the first scan), T g grew much more rapidly with w DVB over the entire range of up to w DVB =0.2458 that was studied.
FIG. 2 provides an idealized, generic and schematic two-dimensional illustration of how a very small volume fraction of a nanofiller may be able to “span” and thus “bridge through” a vast amount of space, thus potentially enhancing the load bearing ability of the matrix polymer significantly at much smaller volume fractions than possible with conventional fillers.
FIG. 3 illustrates the “aggregates” in which the “primary particles” of nanofillers such as nanoscale carbon black, fumed silica and fumed alumina commonly occur. Such aggregates may contain many very small primary particles, often arranged in a “fractal” pattern, resulting in aggregate principal axis dimensions that are also shorter than 0.5 microns. These aggregates (and not the individual primary particles that constitute them) are, usually, the smallest units of such nanofillers that are dispersed in a polymer matrix under normal fabrication conditions, when the forces holding the aggregates together in the much larger “agglomerates” are overcome successfully. This illustration was reproduced from the product literature of Cabot Corporation.
FIG. 4 provides an idealized schematic illustration, in the context of the resistance of thermoset polymer particles to compression as a function of the temperature, of the most common benefits of using the methods of the present invention. In most cases, the densification of the crosslinked polymer network via post-polymerization heat treatment will have the main benefit of increasing the softening (and hence also the maximum possible use) temperature, along with improving the environmental resistance. On the other hand, in most cases, nanofiller incorporation will have the main benefits of increasing the stiffness and strength. The use of nanofiller incorporation and post-polymerization heat treatment together, as complementary methods, will thus often be able to provide all (or at least most) of these benefits simultaneously.
FIG. 5 provides a process flow diagram depicting the preparation of the example. It contains four major blocks; depicting the preparation of the aqueous phase (Block A), the preparation of the organic phase (Block B), the mixing of these two phases followed by suspension polymerization (Block C), and the further process steps used after polymerization to obtain the “as-polymerized” and “heat-treated” samples of particles (Block D).
FIG. 6 shows the variation of the temperature with time during polymerization.
FIG. 7 shows the results of the measurement of the glass transition temperatures (T g ) of the three heat-treated thermoset nanocomposite samples via differential scanning calorimetry (DSC). The samples have identical compositions. They differ only as a result of the use of different heat treatment conditions after polymerization. T g was defined as the temperature at which the curve showing the heat flow as a function of the temperature goes through its inflection point.
FIG. 8 provides a schematic illustration of the configuration of the conductivity cell.
FIG. 9 shows the measured liquid conductivity of a packing of particles of 14/16 U.S. mesh size (diameters ranging from 1.19 mm to 1.41 mm) from Sample 40m200C, at a coverage of 0.02 lb/ft 2 , under a closure stress of 4000 psi at a temperature of 190° F., as a function of time.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Because the invention will be understood better after further discussion of its currently preferred embodiments, further discussion of said embodiments will now be provided. It is understood that said discussion is being provided without reducing the generality of the invention, since persons skilled in the art can readily imagine many additional embodiments that fall within the full scope of the invention as taught in the SUMMARY OF THE INVENTION section.
A. Nature, Attributes and Applications of Currently Preferred Embodiments
The currently preferred embodiments of the invention are lightweight thermoset nanocomposite particles possessing high stiffness, strength, temperature resistance, and resistance to aggressive environments. These attributes, occurring in combination, make said particles especially suitable for use in many challenging applications in the construction, drilling, completion and/or fracture stimulation of oil and natural gas wells. Said applications include the use of said particles as a proppant partial monolayer, a proppant pack, an integral component of a gravel pack completion, a ball bearing, a solid lubricant, a drilling mud constituent, and/or a cement additive.
B. Thermoset Polymer Matrix
1. Constituents
The thermoset matrix in said particles consists of a terpolymer of styrene (S, non-crosslinking), ethyvinylbenzene (EVB, also non-crosslinking), and divinylbenzene (DVB, crosslinking). The preference for such a terpolymer instead of a copolymer of S and DVB is a result of economic considerations. To summarize, DVB comes mixed with EVB in the standard product grades of DVB, and the cost of DVB increases rapidly with increasing purity in special grades of DVB. EVB is a non-crosslinking (difunctional) styrenic monomer. Its incorporation into the thermoset matrix does not result in any significant changes in the properties of the thermoset matrix or of nanocomposites containing said matrix, compared with the use of S as the sole non-crosslinking monomer. Consequently, it is far more cost-effective to use a standard (rather than purified) grade of DVB, thus resulting in a terpolymer where some of the repeat units originate from EVB.
2. Proportions
The amount of DVB in said terpolymer ranges from 3% to 35% by weight of the starting mixture of the three reactive monomers (S, EVB and DVB) because different applications require different maximum possible use temperatures. Even when purchased in standard product grades where it is mixed with a large weight fraction of EVB, DVB is more expensive than S. It is, hence, useful to develop different product grades where the maximum possible use temperature increases with increasing weight fraction of DVB. Customers can then purchase the grades of said particles that meet their specific application needs as cost-effectively as possible.
C. Nanofiller
1. Constituents
The Monarch™ 280 product grade of nanoscale carbon black supplied by Cabot Corporation is being used as the nanofiller in said particles. The reason is that it has a relatively low specific surface area, high structure, and a “fluffy” product form; rendering it especially easy to disperse.
2. Proportions
The use of too low a volume fraction of carbon black results in ineffective reinforcement. The use of too high a volume fraction of carbon black may result in difficulties in dispersing the nanofiller, dispersion viscosities that are too high to allow further processing with available equipment, and detrimental interference in polymerization and network formation. The amount of carbon black ranges from 0.1% to 15% by volume of said particles because different applications require different levels of reinforcement. Carbon black is more expensive than the monomers (S, EVB and DVB) currently being used in the synthesis of the thermoset matrix. It is, therefore, useful to develop different product grades where the extent of reinforcement increases with increasing volume fraction of carbon black. Customers can then purchase the grades of said particles that meet their specific application needs as cost-effectively as possible.
D. Polymerization
Suspension polymerization is performed via rapid rate polymerization, as taught by Albright (U.S. Pat. No. 6,248,838) which is incorporated herein by reference, for the fabrication of said particles. Rapid rate polymerization has the advantage, relative to conventional isothermal polymerization, of producing more physical entanglements in thermoset polymers (in addition to the covalent crosslinks). Suspension polymerization involves the preparation of an the aqueous phase and an organic phase prior to the commencement of the polymerization process. The Monarch™ 280 carbon black particles are dispersed in the organic phase prior to polymerization. The most important additional formulation component (besides the reactive monomers and the nanofiller particles) that is used during polymerization is the initiator. The initiator may consist of one type molecule or a mixture of two or more types of molecules that have the ability to function as initiators. Additional formulation components, such as catalysts, inhibitors, dispersants, stabilizers, rheology modifiers, buffers, antioxidants, defoamers, impact modifiers, plasticizers, pigments, flame retardants, smoke retardants, or mixtures thereof, may also be used when needed. Some of the additional formulation component(s) may become either partially or completely incorporated into the particles in some embodiments of the invention.
E. Attainable Particle Sizes
Suspension polymerization produces substantially spherical polymer particles. (While it is a goal of this invention to create spherical particles, it is understood that it is exceedingly difficult as well as unnecessary to obtain perfectly spherical particles. Therefore, particles with minor deviations from a perfectly spherical shape are considered perfectly spherical for the purposes of this disclosure.) Said particles can be varied in size by means of a number of mechanical and/or chemical methods that are well-known and well-practiced in the art of suspension polymerization. Particle diameters attainable by such means range from submicron values up to several millimeters. Hence said particles may be selectively manufactured over the entire range of sizes that are of present interest and/or that may be of future interest for applications in the oil and natural gas industry.
F. Optional Further Selection of Particles by Size
Optionally, after the completion of suspension polymerization, said particles can be separated into fractions having narrower diameter ranges by means of methods (such as, but not limited to, sieving techniques) that are well-known and well-practiced in the art of particle separations. Said narrower diameter ranges include, but are not limited to, nearly monodisperse distributions. Optionally, assemblies of particles possessing bimodal or other types of special distributions, as well as assemblies of particles whose diameter distributions follow statistical distributions such as gaussian or log-normal, can also be prepared.
The optional preparation of assemblies of particles having diameter distributions of interest from any given “as polymerized” assembly of particles can be performed before or after any optional heat treatment of said particles. Without reducing the generality of the invention, in the currently most preferred embodiments of the invention, any optional preparation of assemblies of particles having diameter distributions of interest from the product of a run of the pilot plant or production plant reactor is performed after the completion of any optional heat treatment of said particles.
The particle diameters of current practical interest for various uses in the construction, drilling, completion and/or fracture stimulation of oil and natural gas wells range from 0.1 to 4 millimeters. The specific diameter distribution that would be most effective under given circumstances depends on the details of the subterranean environment in addition to depending on the type of application. The diameter distribution that would be most effective under given circumstances may be narrow or broad, monomodal or bimodal, and may also have other special features (such as following a certain statistical distribution function) depending on both the details of the subterranean environment and the type of application.
G. Optional Heat Treatment
Said particles are left in the reactor fluid that remains after suspension polymerization if optional heat treatment is to be used. Said reactor fluid thus serves as the heat treatment medium. This approach works especially well (without adverse effects such as degradation and/or swelling) in enhancing the curing of said particles where the polymer matrix consists of a terpolymer of S, EVB and DVB. Since the reactor fluid that remains after the completion of suspension polymerization is aqueous while these terpolymers are very hydrophobic, the reactor fluid serves as an excellent heat transfer medium which does not swell the particles. The use of the reactor fluid as the medium for the optional heat treatment also has the advantage of simplicity since the particles would have needed to be removed from the reactor fluid and placed in another fluid as an extra step before heat treatment if an alternative fluid had been required.
Detailed and realistic simulations based on the solution of the heat transfer equations are often used optionally to optimize the heat exposure schedule if optional heat treatment is to be used. It has been found that such simulations become increasingly useful with increasing quantity of particles that will be heat treated simultaneously. The reason is the finite rate of heat transfer. Said finite rate results in slower and more difficult equilibration with increasing quantity of particles and hence makes it especially important to be able to predict how to cure most of the particles further uniformly and sufficiently without overexposing many of the particles to heat.
Example
The currently preferred embodiments of the invention will be understood better in the context of a specific example. It is to be understood that said example is being provided without reducing the generality of the invention. Persons skilled in the art can readily imagine many additional examples that fall within the scope of the currently preferred embodiments as taught in the DETAILED DESCRIPTION OF THE INVENTION section. Persons skilled in the art can, furthermore, also readily imagine many alternative embodiments that fall within the full scope of the invention as taught in the SUMMARY OF THE INVENTION section.
A. Summary
The thermoset matrix was prepared from a formulation containing 10% DVB by weight of the starting monomer mixture. The DVB had been purchased as a mixture where only 63% by weight consisted of DVB. The actual polymerizable monomer mixture used in preparing the thermoset matrix consisted of roughly 84.365% S, 5.635% EVB and 10% DVB by weight.
Carbon black (Monarch 280) was incorporated into the particles, at 0.5% by weight, via dispersion in the organic phase of the formulation prior to polymerization. Since the specific gravity of carbon black is roughly 1.8 while the specific gravity of the polymer is roughly 1.04, the amount of carbon black incorporated into the particles was roughly 0.29% by volume.
Suspension polymerization was performed in a pilot plant reactor, via rapid rate polymerization as taught by Albright (U.S. Pat. No. 6,248,838) which is incorporated herein by reference. In applying this method, the “dual initiator” approach, wherein two initiators with different thermal stabilities are used to help drive the reaction of DVB further towards completion, was utilized.
The required tests only require a small quantity of particles. The use of a liquid medium (such as the reactor fluid) is unnecessary for the heat treatment of a small sample. Roughly 500 grams of particles were hence removed from the slurry, washed, spread very thin on a tray, heat-treated for ten minutes at 200° C. in an oven in an inert gas environment, and submitted for testing.
The glass transition temperature of these “heat-treated” particles, and the liquid conductivity of packings thereof, were then measured by independent testing laboratories (Impact Analytical in Midland, Mich., and FracTech Laboratories in Surrey, United Kingdom, respectively).
FIG. 5 provides a process flow diagram depicting the preparation of the example. It contains four major blocks; depicting the preparation of the aqueous phase (Block A), the preparation of the organic phase (Block B), the mixing of these two phases followed by suspension polymerization (Block C), and the further process steps used after polymerization to obtain the “as-polymerized” and “heat-treated” samples of particles (Block D).
The following subsections will provide further details on the formulation, preparation and testing of this working example, to enable persons who are skilled in the art to reproduce the example.
B. Formulation
An aqueous phase and an organic phase must be prepared prior to suspension polymerization. The aqueous phase and the organic phase, which were prepared in separate beakers and then used in the suspension polymerization of the particles of this example, are described below.
1. Aqueous Phase
The aqueous phase used in the suspension polymerization of the particles of this example, as well as the procedure used to prepare said aqueous phase, are summarized in TABLE 1. TABLE 1. The aqueous phase was prepared by adding Natrosol Plus 330 and gelatin (Bloom strength 250) to water, heating to 65° C. to disperse the Natrosol Plus 330 and the gelatin in the water, and then adding sodium nitrite and sodium carbonate. Its composition is listed below.
INGREDIENT
WEIGHT (g)
%
Water
1493.04
98.55
Natrosol Plus 330 (hydroxyethylcellulose)
7.03
0.46
Gelatin (Bloom strength 250)
3.51
0.23
Sodium Nitrite (NaNO 2 )
4.39
0.29
Sodium Carbonate (Na 2 CO 3 )
7.03
0.46
Total Weight in Grams
1515.00
100.00
2. Organic Phase
The organic phase used in the suspension polymerization of the particles of this example, as well as the procedure used to prepare said organic phase, are summarized in TABLE 2. Note that the nanofiller (carbon black) was added to the organic phase in this particular example. TABLE 2. The organic phase was prepared by placing the monomers, benzoyl peroxide (an initiator), t-amyl peroxy(2-ethylhexyl)monocarbonate (TAEC, also an initiator), Disperbyk-161 and carbon black together and agitating the resulting mixture for at least 15 minutes to disperse carbon black in the mixture. Its composition is listed below. After taking the other components of the 63% DVB mixture into account, the polymerizable monomer mixture actually consisted of roughly 84.365% S, 5.635% EVB and 10% DVB by weight. The total polymerizable monomer weight of was 1356.7 grams. The resulting thermoset nanocomposite particles thus contained [100×6.8/(1356.7+6.8)]=0.5% by weight of carbon black.
INGREDIENT WEIGHT (g) % Styrene (pure) 1144.58 82.67 Divinylbenzene (63% DVB, 98.5% 215.35 15.56 polymerizable monomers) Carbon black (Monarch 280) 6.8 0.49 Benzoyl peroxide 13.567 0.98 t-Amyl peroxy(2- 4.07 0.29 ethylhexyl)monocarbonate (TAEC) Disperbyk-161 0.068 0.0049 Total Weight in Grams 1384.435 100
C. Preparation of Particles from Formulation
Once the formulation is prepared, its aqueous and organic phases are mixed, polymerization is performed, and “as-polymerized” and “heat-treated” particles are obtained, as described below.
1. Mixing
The aqueous phase was added to the reactor at 65° C. The organic phase was then introduced over roughly 5 minutes with agitation at the rate of 90 rpm. The mixture was held at 65° C. with stirring at the rate of 90 rpm for at least 15 minutes or until proper dispersion had taken place as manifested by the equilibration of the droplet size distribution.
2. Polymerization
The temperature was ramped from 65° C. to 78° C. in 10 minutes. It was then further ramped from 78° C. to 90° C. at the rate of 0.1° C. per minute in 120 minutes. It was then held at 90° C. for 90 minutes to provide most of the conversion of monomer to polymer, with benzoyl peroxide (half life of one hour at 92° C.) as the effective initiator. It was then further ramped to 115° C. in 30 minutes and held at 115° C. for 180 minutes to advance the curing with TAEC (half life of one hour at 117° C.) as the effective initiator. The particles were thus obtained in an aqueous slurry. FIG. 6 shows the variation of the temperature with time during polymerization.
3. “As-Polymerized” Particles
The aqueous slurry was cooled to 40° C. It was then poured onto a 60 mesh (250 micron) sieve to remove the aqueous reactor fluid as well as any undesirable small particles that may have formed during polymerization. The “as-polymerized” beads of larger than 250 micron diameter obtained in this manner were then washed three times with warm (40° C. to 50° C.) water
4. “Heat-Treated” Particles
Three sets of “heat-treated” particles, which were imposed to different thermal histories during the post-polymerization heat treatment, were prepared from the “as-polymerized” particles. In preparing each of these heat-treated samples, washed beads were removed from the 60 mesh sieve, spread very thin on a tray, placed in an oven under an inert gas (nitrogen) blanket, and subjected to the desired heat exposure. Sample 10m200C was prepared with isothermal annealing for 10 minutes at 200° C. Sample 40m200C was prepared with isothermal annealing for 40 minutes at 200° C. to explore the effects of extending the duration of isothermal annealing at 200° C. Sample 10m220C was prepared with isothermal annealing for 10 minutes at 220° C. to explore the effects of increasing the temperature at which isothermal annealing is performed for a duration of 10 minutes. In each case, the oven was heated to 100° C., the sample was placed in the oven and covered with a nitrogen blanket; and the temperature was then increased to its target value at a rate of 2° C. per minute, held at the target temperature for the desired length of time, and finally allowed to cool to room temperature by turning off the heat in the oven. Some particles from each sample were sent to Impact Analytical for the measurement of T g via DSC.
Particles of 14/16 U.S. mesh size were isolated from Sample 40m200C by some additional sieving. This is a very narrow size distribution, with the particle diameters ranging from 1.19 mm to 1.41 mm. This nearly monodisperse assembly of particles was sent to FracTech Laboratories for the measurement of the liquid conductivity of its packings.
D. Reference Sample
A Reference Sample was also prepared, to provide a baseline against which the data obtained for the particles of the invention can be compared.
The formulation and the fabrication process conditions used in the preparation of the Reference Sample differed from those used in the preparation of the examples of the particles of the invention in two key aspects. Firstly, carbon black was not used in the preparation of the Reference Sample. Secondly, post-polymerization heat treatment was not performed in the preparation of the Reference Sample. Consequently, while the examples of the particles of the invention consisted of a heat-treated and carbon black reinforced thermoset nanocomposite, the particles of the Reference Sample consisted of an unfilled and as-polymerized thermoset polymer that has the same composition as the thermoset matrix of the particles of the invention.
Some particles from the Reference Sample were sent to Impact Analytical for the measurement of T g via DSC. In addition, particles of 14/16 U.S. mesh size were isolated from the Reference Sample by sieving and sent to FracTech Laboratories for the measurement of the liquid conductivity of their packings.
E. Differential Scanning Calorimetry
DSC experiments (ASTM E1356-03) were carried out by using a TA Instruments Q100 DSC with nitrogen flow of 50 mL/min through the sample compartment. Roughly nine milligrams of each sample were weighed into an aluminum sample pan, the lid was crimped onto the pan, and the sample was then placed in the DSC instrument. The sample was then scanned from 5° C. to 225° C. at a rate of 10° C. per minute. The instrument calibration was checked with NIST SRM 2232 indium. Data analysis was performed by using the TA Universal Analysis V4.1 software.
DSC data for the heat-treated samples are shown in FIG. 7 . T g was defined as the temperature at which the curve for the heat flow as a function of the temperature went through its inflection point. The results are summarized in TABLE 3. It is seen that the extent of polymer curing in Sample 10m220C is comparable to that in Sample 40m200C, and that the extent of polymer curing in both of these samples has advanced significantly further than that in Sample 10m200C whose T g was only slightly higher than that of the Reference Sample. TABLE 3. Glass transitions temperatures (T g ) of the three heat-treated samples and of the Reference Sample, in ° C. In addition to being an “as-polymerized” (rather than a heat-treated) sample, the Reference Sample also differs from the other three samples since it is an unfilled sample while the other three samples each contain 0.5% by weight carbon black.
ISOTHERMAL HEAT SAMPLE TREATMENT IN NITROGEN T g (° C.) Reference Sample None 117.17 10m200C For 10 minutes at a temperature of 200° C. 122.18 10m220C For 10 minutes at a temperature of 220° C. 131.13 40m200C For 40 minutes at a temperature of 200° C. 131.41
F. Liquid Conductivity Measurement
A fracture conductivity cell allows a particle packing to be subjected to desired combinations of compressive stress (simulating the closure stress on a fracture in a downhole environment) and elevated temperature over extended durations, while the flow of a fluid through the packing is measured. The flow capacity can be determined from differential pressure measurements. The experimental setup is illustrated in FIG. 8 .
Ohio sandstone, which has roughly a compressive elastic modulus of 4 Mpsi and a permeability of 0.1 mD, was used as a representative type of outcrop rock. Wafers of thickness 9.5 mm were machined to 0.05 mm precision and one rock was placed in the cell. The sample was split to ensure that a representative sample is achieved in terms of its particle size distribution and then weighed. The particles were placed in the cell and leveled. The top rock was then inserted. Heated steel platens were used to provide the correct temperature simulation for the test. A thermocouple inserted in the middle port of the cell wall recorded the temperature of the pack. A servo-controlled loading ram provided the closure stress. The conductivity of deoxygenated silica-saturated 2% potassium chloride (KCl) brine of pH 7 through the pack was measured.
The conductivity measurements were performed by using the following procedure:
1. A 70 mbar full range differential pressure transducer was activated by closing the bypass valve and opening the low pressure line valve. 2. When the differential pressure appeared to be stable, a tared volumetric cylinder was placed at the outlet and a stopwatch was started. 3. The output of the differential pressure transducer was fed to a data logger 5-digit resolution multimeter which logs the output every second during the measurement. 4. Fluid was collected for 5 to 10 minutes, after which time the flow rate was determined by weighing the collected effluent. The mean value of the differential pressure was retrieved from the multimeter together with the peak high and low values. If the difference between the high and low values was greater than the 5% of the mean, the data point was disregarded. 5. The temperature was recorded from the inline thermocouple at the start and at the end of the flow test period. If the temperature variation was greater than 0.5° C., the test was disregarded. The viscosity of the fluid was obtained from the measured temperature by using viscosity tables. No pressure correction is made for brine at 100 psi. The density of brine at elevated temperature was obtained from these tables. 6. At least three permeability determinations were made at each stage. The standard deviation of the determined permeabilities was required to be less than 1% of the mean value for the test sequence to be considered acceptable. 7. At the end of the permeability testing, the widths of each of the four corners of the cell were determined to 0.01 mm resolution by using vernier calipers.
The test results are summarized in TABLE 4.
TABLE 4. Measurements on packings of 14/16 U.S. mesh size of Sample 40m200C and of the Reference Sample at a coverage of 0.02 lb/ft 2 . The conductivity (mDft) of deoxygenated silica-saturated 2% potassium chloride (KCl) brine of pH 7 through each sample was measured at a temperature of 190° F. (87.8° C.) under a compressive stress of 4000 psi (27.579 MPa).
Reference Sample
Sample 40m200C
Time (hours)
Conductivity (mDft)
Time (hours)
Conductivity (mDft)
27
1179
45
1329
49
1040
85
1259
72
977
109
1219
97
903
133
1199
120
820
157
1172
145
772
181
1151
168
736
205
1126
192
728
233
1110
218
715
260
720
These results are shown in FIG. 9 . They demonstrate clearly the advantage of the particles of the invention in terms of the enhanced retention of liquid conductivity under a compressive stress of 4000 psi at a temperature of 190° F. | Use of two different methods, either each by itself or in combination, to enhance the stiffness, strength, maximum possible use temperature, and environmental resistance of thermoset polymer particles is disclosed. One method is the application of post-polymerization process steps (and especially heat treatment) to advance the curing reaction and to thus obtain a more densely crosslinked polymer network. The other method is the incorporation of nanofillers, resulting in a heterogeneous “nanocomposite” morphology. Nanofiller incorporation and post-polymerization heat treatment can also be combined to obtain the benefits of both methods simultaneously. The present invention relates to the development of thermoset nanocomposite particles. Optional further improvement of the heat resistance and environmental resistance of said particles via post-polymerization heat treatment; processes for the manufacture of said particles; and use of said particles in the construction, drilling, completion and/or fracture stimulation of oil and natural gas wells are described. | 2 |
BACKGROUND OF THE INVENTION
The invention relates to outdoor signs and, in particular, to temporary ground signs.
PRIOR ART
Sign manufacturers currently use a plastic sheet product commonly known as corrugated plastic for face material of temporary and/or inexpensive signs. Typically, vinyl graphics comprising letters or other images cut out of adhesive backed colored vinyl sheet are applied to such corrugated sheets at local sign shops. In outdoor usage, it is common to construct a ground sign with a leg or legs that can be driven into the ground to anchor the sign and support the face or faces. Attempts have been made to utilize corrugated plastic material for outdoor ground signs but the results have often been unsatisfactory. Known constructions are subject to wind damage or to damage from light impacts. Additionally, certain sign frames present a risk of injury should a person fall against upstanding barbs of the frame that are inserted into the corrugations of the sign face material to effect their assembly.
SUMMARY OF THE INVENTION
The invention provides a durable and inexpensive outdoor ground sign assembled from corrugated plastic sign face material and metal rod. The frame is in the shape of an inverted U and the sign face is hung from the horizontal bight portion of the frame. An extruded plastic channel snaps over the horizontal frame bight section and grips the faces of the corrugated sheet or panel. The assembly procedure is relatively simple and very quick thereby reducing labor cost. The channel remains loose on the frame and enables the sign to resist strong winds and impacts by allowing the sign face panel to swing upwardly to reduce its effective area and wind resistance and/or to absorb impact energy.
In situations where it is desirable to stabilize the sign face panel against swinging such as by customer preference or local zoning ordinances, the sign is provided with clip elements that fasten the lower edge of the sign face panel to adjacent areas of the legs. The clip elements are configured to securely hold the sign face panel while avoiding projecting elements which could pose a risk to a person in the event he or she accidentally fell against it.
One or more additional sign face panels can be assembled on the frame. In this optional construction, a secondary cross bar is joined to the legs and an additional corrugated plastic sign face panel is mounted on the secondary bar. The assembly is accomplished with an extruded retaining channel like that used with the main part of the frame and the sign face panel associated with it as described above.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an elevational view of a sign constructed in accordance with the invention;
FIG. 2 is a fragmentary cross-sectional view of the sign taken across the plane indicated by the lines 2--2 in FIG. 1;
FIG. 3 is an elevational view of the sign assembled with accessory clips for locking the sign face panel to the frame legs;
FIG. 4 is a fragmentary exploded perspective view of a typical clip and a portion of the sign face panel;
FIG. 5 is a fragmentary cross-sectional view through the sign taken at the plane 5--5 indicated in FIG. 3;
FIG. 6 is a second embodiment of the invention wherein two sign face panels are provided on a single frame, and
FIG. 7 is a perspective view of a clip used to assemble a cross-bar to the legs in the sign construction of FIG. 6;
DESCRIPTION OF THE PREFERRED EMBODIMENTS
A sign assembly 10 constructed in accordance with the invention is a generally planar rectangular assembly of a rigid metal frame 11 and a sign face panel 12. The frame 11 is preferably formed of steel or other suitable metal wire or rod. The frame can be made of 1/4" diameter galvanized steel wire or rod. Other coating may be applied to the steel wire such as cadmium or paint to provide a protective cover. The frame 11 is fabricated by cold bending a continuous piece into a generally U-shaped configuration that is inverted when used. The U-shape includes a horizontal header or bight portion 16 and symmetrical generally vertical legs 17 depending integrally from the header. The legs 17 are bent with a horizontal offset 18 that forms a foot step to facilitate installation of respective lower portions 19 of the legs 17 into ground. The offsets 18 are each in the plane of the sign assembly 10 and directed towards the opposite leg 17.
The sign face panel 12 is a relatively rigid sheet preferably formed of thermoplastic material such as copolymer polypropylene and known in the sign industry as corrugated plastic. The corrugations or flutes are shown in section in FIG. 5 and are formed by parallel vertical webs 21 that are integrally attached to outer sheets or skins 22 of the sign face panel 12. As shown, the sign panel 12 is largely hollow owing to the corrugation spaces between the webs 21.
The sign assembly 10 includes an extruded thermoplastic channel 23 of suitable material such as polyvinylchloride of a known type such as used in residential siding and window construction and resistant to ultraviolet light. The length of the extrusion or channel 23 ideally is substantially equal to the width of the sign panel 12. By way of example, the sign panel illustrated in FIG. 1 can have a nominal height of 18" and a nominal width of 24". The channel 23 has a somewhat circular cross-section and includes an arcuate U-shaped bight 24 (FIG. 2) and opposed flanges 26. Desirably, the flanges 26 have outwardly flared portions 27 at their free edges. The plastic material of the channel 23 has sufficient resilience to allow it to be snapped over the frame header 16 and to tightly grip the upper edge of the sign panel 12 on its opposite faces with the flanges 26. The re-entrant arcuate or bulbous cross-section of the channel 23 allows its flanges 26 to firmly grip the sign panel 12 while affording a clearance fit around the frame header 16. As a result, the sign panel 12 and channel 23 when installed on the header 16 can swing or pivot about the horizontal axis of the header. This swinging capability allows the sign to withstand strong winds and impacts. When a strong wind occurs, the panel 12 can swing upwardly and reduce its effective face area and thereby reduce the wind force on the sign 10. Similarly, when the panel 12 is struck with an object, it can deflect by pivoting on the header 16 to absorb the energy of the impact. Preferably, the sign panel 12 is arranged so that the longitudinal direction of the corrugation webs 21 is perpendicular to the length of the channel 23. This orientation allows the channel 23 to rigidify and reinforce the sign panel 12 in the direction it is weakest. Preferably, a suitable adhesive or bonding agent 35 such as cyanoacrylate can be used to bond the channel flanges 26 to the faces 31 of the panel 12.
With reference to FIGS. 3 through 5, the sign assembly 10 can be fitted with panel stabilizing clips 36 to prevent the sign panel 12 from swinging in the wind where such motion is undesired. The illustrated clips 36 are identical from side-to-side of the sign assembly 10. A clip 36 is an integral injection-molded part of polyvinylchloride or other thermoplastic material. The clip has an elongated bar 37, upstanding plate-like grips 38, an upstanding prong 39 and a vertically depending arm 40. The plates 38 alternately lie in laterally spaced planes parallel to the plane of the bar 37. The lateral spacing of the plates 38 is slightly less than the thickness of the sign panel 12 so that they frictionally grip the faces 31 of the panel. The upstanding prong or pin 39 extending vertically from the top edge of the bar 37 is adapted to fit snugly into one of the gaps between adjacent corrugation webs 21. In assembly, the prong 39 locks the panel 12 in the slot formed between laterally spaced plates 38. As shown, the prong 39 is centered on the plane between such laterally spaced plates 38.
The depending arm 40 has a vertical groove of generally circular cross-section. The cross-section of the groove 41 is shaped to fit around a respective leg 17 through an arc preferably greater than 180° and is proportioned to resiliently snap over the leg and snugly grip it. It will be seen that the prong 39 is at an end of the bar 37 opposite the end at which the leg gripping arm 40 exists. This construction reduces any concentration of stress on the sign panel 12 which might be imposed by the interconnection between the prong and the panel and the anchoring of the arm 40 on the leg 17.
With reference to FIG. 6, a sign assembly 110 can be provided with more than one sign panel. In this embodiment, elements which are like those described in connection with the first embodiment shown in FIGS. 1 through 5 have been given identical reference numerals. An upper sign panel 12A and a retaining channel 23 have a construction and an assembly on the frame 11 like that described in connection with FIG. 1. A cross bar 46 of material like that forming the frame 11 is secured on the frame in a horizontal position between the legs 17. This is accomplished by using connector brackets 47 shown in FIG. 7. The connector brackets are formed of spring steel or other suitable material. The connector brackets 47 have a portion 48 slid or snapped over the respective end of the cross bar 46 and another portion 49 snapped over a leg 17. The bracket 47 is suitably resilient and strong to maintain the cross bar 46 in a desired vertical location along the legs 17. Barbs 51 may be provided on the brackets 47 to enhance their grip on the legs 17 and cross bar 46. A second panel 12B is assembled on the auxiliary cross bar 46 with a channel 23 in the same manner as previously described in connection with the embodiment of FIG. 1. It will be understood that more than one auxiliary panel can be assembled on the frame 11 and that the frame can be proportionately elongated in the vertical direction to accommodate such additional panels.
The disclosed sign construction is economical to produce by virtue of its inexpensive componentry and minimal labor content. The assembly is light in weight and practical to ship when fully assembled. The sign is durable in use since it is resistant to damage from wind and impacts. The sign avoids risk to the user and general public since it avoids sharp edges and rigid projections. The assembly is particularly suited for shipment to local sign shops where it can have custom vinyl graphics applied to it, for example.
While the invention has been shown and described with respect to particular embodiments thereof, this is for the purpose of illustration rather than limitation, and other variations and modifications of the specific embodiments herein shown and described will be apparent to those skilled in the art all within the intended spirit and scope of the invention. Accordingly, the patent is not to be limited in scope and effect to the specific embodiments herein shown and described nor in any other way that is inconsistent with the extent to which the progress in the art has been advanced by the invention. | An outdoor sign construction comprising an inverted U-shaped wire frame and a rectangular corrugated plastic face panel. The sign face panel is retained on a horizontal header section of the frame between vertical frame legs by a resilient extruded plastic channel assembled around the header and out the top edge of the panel. The panel can be allowed to swing on the frame header or can be fixed against such movement by optional brackets. A secondary header and auxiliary sign panel can be assembled on the frame. | 6 |
BACKGROUND OF THE INVENTION
Solvent dyeing of textile fibers and fabrics has become increasingly important in the industry's efforts to reduce waste discharged to our environment as well as increase productivity of the dyeing process. The more successful approaches to utilization of solvents to replace water in the dyeing processes suffer from the physico-chemical property differences between solvents and water, as, for example, high solubility of dyestuffs in the solvent resulting in poor dye yields, low distribution coefficients of solvent-soluble dyestuffs with fibers resulting in a poor distribution of dyestuff between the fiber and the solvent. These two properties alone make solvent dyeing unattractive for large volume uses.
Further, conventional aqueous dyeing techniques generate large quantities of waste material which previously had been dumped into streams creating ecological problems.
It therefore would be advantageous to have a process which could dye fibers, particularly polyester fibers, employing solvents which, in spite of the physico-chemical properties of the solvent-dye system, can obtain a substantial exhaustion of the dyestuff from the solvent.
The invention described herein permits the recycle of all of the fluids of solvent and water because less chemical additives are used than in the conventional dispersed dye system for polyester fibers. Additionally, the use of the solvent, with its inherent low latent heat of vaporization, permits distillation at locations where fuel costs are economical. The present invention also reduces the amount of fluids necessary for dyeing, thus permitting the use of means such as distillation, carbon adsorption, reverse osmosis, biodegradation, flocculation, filtration or combinations thereof as needed to purify and recycle substantially all of the fluids.
BRIEF DESCRIPTION OF THE INVENTION
In accordance with the present invention, polyester fiber can be dyed from a solvent, such as a chlorinated solvent, using dyestuffs soluble in the solvent with or without the aid of cosolvents by contacting the fiber with a volume of a solution of the dyestuff sufficient to carry the required amount of dyestuff to dye the fiber to the shade desired. The volume of solution of dyestuff and solvent, if insufficient to fill the dye system, is augmented with enough nonsolvent, e.g., water, to supply that volume. The fiber is contacted with the dyebath at a temperature to dye the fiber. Solvent content of the dyebath is reduced during the contacting step by distillation of the solvent while maintaining a substantially constant volume of liquid in the system by replacing the solvent removed with a nonsolvent, e.g., water. The dyeing step is completed when substantially all of the solvent has been removed from the system and the temperature of the fibers and liquid is such that the dyestuff will diffuse into the fiber. The liquid remaining in the system is drained, preferably while hot, and the fiber scoured with solvent or in a conventional manner and dried as necessary. The process is operated under a pressure to obtain the necessary dyeing temperature and the solvent is distilled from the dyebath by flash evaporation of an azeotrope of the solvent and nonsolvent from the dyebath. One convenient method for accomplishing this is to supply the nonsolvent as water in the form of liquid and steam to maintain a constant liquid volume. In this method, the steam upon contacting the liquid supplies the heat of evaporation of the solvent, viz., an azeotrope of solvent-nonsolvent, to the system as well as part of the make-up nonsolvent, e.g., water. This gaseous azeotrope mixture is then used under pressure in a heat exchanger to distill water from a previous cycle to purify it for a future cycle. Another method for supplying the heat of vaporization of the liquid is to employ an external source of heat through a heat exchanger.
Finally, the fiber is dried and/or scoured if necessary with solvent which is recovered from the scouring step by either steam distillation or a confined drying process.
Other means for purification of the solvent and nonsolvent may also be employed, as for example, adsorptive processes, reverse osmosis, flocculation, filtration or a combination of these various means.
DETAILED DESCRIPTION OF THE INVENTION
The following detailed description of the process of the present invention has particular reference to the drawings.
The drawing illustrates a schematic diagram of a batch dye process such as employed to kier-dye yarns. A kier 10 is provided with external piping 11 and 12 which permit introduction of liquid into and out of the kier 10. For sake of clarity, piping 12 is illustrated as connecting with the multi-holed mandrel 13 interior of kier 10 and upon which the yarn packages 14 are positioned in the kier 10. A valve 15 is positioned in piping 11 and 12 to enable fluid to be directed into piping 11 and into the kier 10 through the mandrel 13 and withdrawn from the interior of kier 10 through piping 12 or to be introduced through piping 12 into the interior of kier 10 and withdrawn through mandrel 13 into piping 12. Connected to valve 15 is a pump 16 and its associated piping 17 and leading away from the valve 15 is piping 18 provided with a steam mixing section 19 prior to its termination in expansion flash chamber 20. Expansion flash chamber 20 is connected from its lower extent to the intake of pump 16. Mixing section 19 is provided with a steam line 21 from a boiler 22. A separate line 23 from steam line 21 connects to the piping 17 and is provided with a valve 24 which controls the admission of steam into the kier 10 if and when there is a desire to contact packages 14 with direct steam. Another separate line 25 extends from steam line 21 into the lower portion of the expansion flash chamber 20 to provide auxiliary heat to the expansion flash chamber 20 as required. This line 25 is valved at 26. The top of expansion flash chamber 20 is connected through piping 27 and pressure regulator 28 into heat exchanger 29 in a still 30. The heat exchanger 29 is connected on its outlet side to a condenser 31 through piping 32 and pressure regulator 32a. Thus, expansion flash chamber 20 is connected through piping 27 and its pressure regulator 28 to heat exchanger 29 in still 30, directing vapors from expansion flash chamber 20 into heat exchanger 29 of still 30. The pressure regulator 28 effectively controls the temperature of the vapors leaving flash chamber 20 in a manner to provide the requisite or a part of the requisite BTU's necessary to vaporize the water in still 30. The vapors and any condensate in heat exchanger 29 are directed to the condenser 31 through piping 32 and pressure regulator 32a. The vapors generated in still 30 are directed to condenser 31 through line 30a. Condenser 31 has an atmospheric vent 31a. The condensate from condenser 31 is directed to a water separator 33 and the water separated in separator 33 is directed to clean water storage 34 through piping 35. The solvent separated in separator 33 is directed to clean solvent storage 36 through piping 37. Both storage reservoirs 34 and 36 are connected with piping 38 and 39, respectively, to a line 40 to provide fluid to the pump 16 when required. Pipe 38 is provided with valve 41 and line 39 is provided with valve 42 to control the flow of fluid from the respective storages.
Still 20 and kier 10 are joined with pipe 43 to transfer liquid to flash still 30 by manipulation of valve 44 in pipe 43. Still 30 is further provided with a second heat exchanger 45 connected to the boiler 22 by line 46.
A solvent removal still 48 is connected to the clean water storage 34 through line 49, the solvent vapors going overhead through line 48A to condenser 31 and the water being taken off the bottom through line 50 to the boiler feed 47. A heat exchanger 51 located in still 48 is connected to the boiler feed 47 with condensate being returned to the boiler feed 47 through line 52. In a similar fashion, condensate is returned to line 52 from heat exchanger 45 with line 52A and heat exchanger 25 with line 52B.
A dryer section is provided with a drying chamber 53 for receiving wet yarn from kier 10. The dryer 53 is illustrated as a hot moist air-recycle dryer. The air is heated in exchanger 54 and delivered to chamber 53 through ducting 55. The air with its associated water and/or solvent vapor is withdrawn from chamber 53 through ducting 56 and passed through a condenser 57. The dehumidified air is drawn from the condenser 57 through ducting 58 by fan 59 and delivered to the heat exchanger 54. Steam is provided to heater 54 through piping 60 from boiler 22 and the condensate 52C from the exchanger 54 is returned to the boiler feed 47 through to line 52. Condensate 57A removed from the air in condenser 57 is delivered to the solvent recovery still 48 wherein any solvent is sent to condenser 31 and any water is sent to the boiler feed 47.
Dye preparation tank 62 is provided with piping 63 and 61 to both the clean solvent 36 and clean water 34 storages and an outlet through piping 64 to the kier 10 through pump 16. Tank 62 is provided with stirring means 65. Dye in either liquid, paste or powder form is added to tank 62 by pipe 66. Steam line 62A and associated valve 62B is provided to heat dye tank 62 as needed.
Having described the equipment and its piping and auxiliaries, the operation of such equipment in accordance with the process of the present invention will be described:
The kier 10 was loaded with a yarn package, weighing about 500 grams, of 150/35 polyester yarn and the kier 10 closed. A dyestuff, for example, 10 grams of Resolin Brilliant Yellow 7GL (CI disperse Yellow 93) obtained free of dispersing agent as a press-cake from the manufacturer was dissolved in 500 ml. of perchloroethylene to produce a dye solution based on the weight of fiber (owf) to be dyed at a level of 2% owf. The total liquid volume was made up to about 11/2 gallons in dye tank 62 by adding water with stirring to produce a two-phase system. This liquid was pumped into kier 10 which was vented until the kier was full and substantially free of air. The two-phase liquid system (water and perchloroethylene-dye mixture) was maintained, admixed by stirring and circulation through the piping and kier 10 with pump 16. The pump 16 continued to draw liquid from the dye preparation 62 tank until the equipment (kier 10, pump 16, expansion chamber 20 and associated piping) was full and a level of liquid was maintained in the lower portion of the expansion flash chamber 20. Withdrawal of liquid from the dye preparation tank 62 was stopped and steam admitted to mixing section 19. The pump 16 continued to circulate liquid through the dye equipment. As the liquid was heated, pressure began to build up in the system as the temperature approached the water-perchloroethylene azeotrope boiling point under the back-pressure established by pressure regulator 28. As the temperature of the liquid in the system increased, the azeotrope vapors passed through the pressure regulator 28, thus removing the solvent from the system as a water-solvent azeotrope. The pressure at which the azeotrope will escape the system is set to maintain the liquid in the system at the dyeing temperature, in this example, 130°C. When the solvent had been substantially removed from the system, the kier 10 was drained to the still 30 while hot, followed by reducing the pressure to atmospheric pressure and the yarn removed. The yarn was wet with water and contained about 0.2 weight percent perchloroethylene retained in the fiber. The yarn was dried in an oven at 105°C.
The dried yarn was knit into a sleeve. Portions of this sleeve were used to conduct various tests. About 1/3 of the sleeve was conventional scoured, 1/3 solvent scoured, while the remainder was unscoured. The conventional scouring used a scouring liquid containing 1 g./l. of sodium hydrosulfite and 1 g./l. of caustic soda was charged to the kier and circulated for 20 minutes at 180°F. (ca. 82.5°C.), drained, and followed by a water rinse containing 1% acetic acid at 180°F. for 10 minutes.
Solvent scouring was carried out by stirring 20 grams of the dry dyed knit stocking in 400 milliliters of perchloroethylene for 10 minutes, followed by air drying before testing. Three temperatures were employed to scour three 20-gram portions of each dyed knit stocking; 50°, 60° and 70°C. The results obtained indicate that solvent scouring is time-temperature related. At 50° and 60°C., about equivalent results were obtained, but at 70°C. for 10 minutes, some loss in wash fastness was observed. Therefore, the data reported is that for 50°C. for 10 minutes since this is nearest to, although above, the temperature one employs in commercial dry cleaning processes. It is expected that higher temperatures will necessitate shorter periods of contact with the solvent.
Each scouring was followed by drying. Portions of each sleeve scoured by each technique were then subjected to Light Fastness Test AATCC 16A-1964, Wash Fastness Test AATCC 61-1962, Dry Cleaning Test AATCC 85-1960T, Crocking Fastness Test AATCC 8-1961, tensile strength and percent elongation of the yarn was tested on an Instron machine, reflectometer readings, as well as analysis of yarn dye bath and scour liquors for dye exhaustion and overall material balance.
In order to obtain a comparison of the present process with a conventional dye technique using a disperse dye, water and conventional dye assistants, another package of the same yarn was dyed according to the following conventional dye process:
A pressure kier was charged with one yarn package (approximately 500 grams yarn) of 150/35 polyester yarn and filled with a bath containing 1% by weight Basol WS, a surfactant, 1% acetic acid, 4% Tanavol, a dye carrier and 1/4% of the sodium salt of ethylenediamine tetraacetic acid in water. The bath was pumped through the system and heated to 120°F. (ca. 49°C.) and upon reaching 120°F. was maintained thereat for 10 minutes. A predispersed dye, CI Disperse Yellow 93 (as manufactured containing dispersants) was added to the bath in an amount to give 2% dye owf. Actual active dyestuff in this commercial product is about 25% of the total weight of the manufactured dyestuff. The bath was pumped with heating to maintain the temperature at 120°F. for 10 minutes. Following this period, the bath was heated to 180°F. at a rate of 3°F./min.; this step took 20 minutes. The kier was sealed and the temperature of the bath raised to 265°F. at a rate of 3°F./min.; this step took 28 minutes. The bath was continuously circulated through the kier during this period. The kier temperature was maintained at 265°F. (ca. 130°C.) for 45 minutes. The bath was then permitted to cool to 200°F. (ca. 93°C.) while circulating the bath through the kier. Upon reaching 200°F., the waste dye solution was drained from the kier and cool water was admitted with circulation to rinse the package and kier free of dye solution and the rinse water drained. The yarn was dried in an oven at 105°C. The dried yarn was knit into a sleeve which was subjected to the same tests as the yarn dyed in accordance with the present invention.
The results of these tests on the various yarns are set forth below:
Conventional Disperse Dyeing Present Invention Unscoured Unscoured Conv. Scoured Solvent Scoured***__________________________________________________________________________Light Fastness 12-15 hours 20 20 hrs. --(AATCC 16A-1964)Wash Fastness, Shade Change 5 5 5 5(AATCC 62-1969) Staining AN** 3 4 4 4+ Staining WSV** 5 5 5Dry Cleaning, Shade Change 5 5 5 5(AATCC 85-1960T Staining 4 + NV** 5ANWSVC** 4 + AN** 5AN** Staining 5 AWSC** -- 5WSVC** 5WSVC**Crocking, Dry 4 4 4+ 5(AATC 8-1969), Wet 4+ 4+ 5 5Tensile Instron 666 grams 636 -- --Elongation Instron 31.5% 28.6 -- --Color reading (sepectrophotometer) 2.30 2.50 -- --2% owf. 10 g./l.Dye fixed 6.45 g. 6.51 g. -- --Dye unfixed 0.23 0.17 -- --Unexhausted 0.32 0.06 -- --Dye lost 3.0 3.26 -- --__________________________________________________________________________ *Scale 1 to 5; 1-poorest, 5-best **A = acetate; N = nylon; W = wool; S = silk; V = viscose; C = cotton ***50°C. perchloroethylene contacted for ten minutes
Although this example used yarn wound in package form, fibers in the form of staple, filament, woven or knitted fabric are considered to be suitable to dye in a similar fashion when using the proper machinery for handling the desired form of fiber.
This method used perchloroethylene as the preferred solute for the dye but other solvents such as the chlorinated hydrocarbon solvents, e.g., 1,1,1-trichloroethane, methylene chloride; the fluorocarbons, e.g., 1,1,2,2-tetrachloro - 1,2-difluoroethane (F112), 1,1,2-trichloro - 1,2,2-trifluoroethane (F113), may be considered as suitable solutes depending on dye or fiber selected. | A method for dyeing polyester fibers by contacting the fiber, which may be in the form of loose fibers or staple, filament or texturized yarn, woven or knitted fabric, with a solution of a soluble dyestuff in a suitable solvent, such as a chlorinated solvent, reducing the volume of the solute in contact with the fiber while maintaining the volume of liquid in contact with the fiber substantially constant by addition of a nonsolvent, maintaining the temperature of the fiber and contacting solvent-nonsolvent at a temperature to effect dyeing. The process also includes the procedures for purifying the solvent and nonsolvent to enable their reuse (recycling) in the process economically and reducing the waste material from the process.
The process also provides for scouring and/or drying the fiber if such be necessary. | 3 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to covering devices and more particularly pertains to an weighted pool cover perimeter anchor for securing a perimeter of a cover about a pool.
2. Description of the Prior Art
The use of covering devices is known in the prior art. More specifically, covering devices heretofore devised and utilized are known to consist basically of familiar, expected and obvious structural configurations, notwithstanding the myriad of designs encompassed by the crowded prior art which have been developed for the fulfillment of countless Objectives and requirements.
Known prior art covering devices include U.S. Pat. No. 3,520,004; U.S. Pat. No. 4,815,152; and U.S. Pat. No. 5,068,929.
While these devices fulfill their respective, particular objectives and requirements, the aforementioned patents do not disclose a weighted pool cover perimeter anchor for securing a perimeter of a cover about a pool which includes an elongated anchor means positionable about a perimeter of a pool, and securing straps coupling the anchor means to the perimeter edge of a cover extending over the pool, whereby the anchor means includes a plurality of conduits which can be filled with water to increase a weight of the anchor assembly to a desired amount for securing the cover relative to the pool.
In these respects, the weighted pool cover perimeter anchor according to the present invention substantially departs from the conventional concepts and designs of the prior art, and in so doing provides an apparatus primarily developed for the purpose of securing a perimeter of a cover about a pool.
SUMMARY OF THE INVENTION
In view of the foregoing disadvantages inherent in the known types of covering devices now present in the prior art, the present invention provides a new weighted pool cover perimeter anchor construction wherein the same can be utilized for securing a perimeter of a cover about a pool. As such, the general purpose of the present invention, which will be described subsequently in greater detail, is to provide a new weighted pool cover perimeter anchor apparatus and method which has many of the advantages of the covering devices mentioned heretofore and many novel features that result in a weighted pool cover perimeter anchor which is not anticipated, rendered obvious, suggested, or even implied by any of the prior art covering devices, either alone or in any combination thereof.
To attain this, the present invention generally comprises an anchor for securing a perimeter of a cover about a pool. The inventive device includes an elongated anchor assembly positionable about the perimeter of the pool. Securing straps couple the anchor assembly to the perimeter edge of a cover extending over the pool. The anchor assembly is preferably formed of a plurality of conduits which can be filled with water to increase a weight of the anchor assembly to a desired amount.
There has thus been outlined, rather broadly, the more important features of the invention in order that the detailed description thereof that follows may be better understood, and in order that the present contribution to the art may be better appreciated. There are additional features of the invention that will be described hereinafter and which will form the subject matter of the claims appended hereto.
In this respect, before explaining at least one embodiment of the invention in detail, it is to be understood that the invention is not limited in its application to the details of construction and to the arrangements of the components set forth in the following description or illustrated in the drawings. The invention is capable of other embodiments and of being practiced and carried out in various ways. Also, it is to be understood that the phraseology and terminology employed herein are for the purpose of description and should not be regarded as limiting.
As such, those skilled in the art will appreciate that the conception, upon which this disclosure is based, may readily be utilized as a basis for the designing of other structures, methods and systems for carrying out the several purposes of the present invention. It is important, therefore, that the claims be regarded as including such equivalent constructions insofar as they do not depart from the spirit and scope of the present invention.
Further, the purpose of the foregoing abstract is to enable the U.S. Patent and Trademark Office and the public generally, and especially the scientists, engineers and practitioners in the art who are not familiar with patent or legal terms or phraseology, to determine quickly from a cursory inspection the nature and essence of the technical disclosure of the application. The abstract is neither intended to define the invention of the application, which is measured by the claims, nor is it intended to be limiting as to the scope of the invention in any way.
It is therefore an object of the present invention to provide a new weighted pool cover perimeter anchor apparatus and method which has many of the advantages of the covering devices mentioned heretofore and many novel features that result in a weighted pool cover perimeter anchor which is not anticipated, rendered obvious, suggested, or even implied by any of the prior art covering devices, either alone or in any combination thereof.
It is another object of the present invention to provide a new weighted pool cover perimeter anchor which may be easily and efficiently manufactured and marketed.
It is a further object of the present invention to provide a new weighted pool cover perimeter anchor which is of a durable and reliable construction.
An even further object of the present invention is to provide a new weighted pool cover perimeter anchor which is susceptible of a low cost of manufacture with regard to both materials and labor, and which accordingly is then susceptible of low prices of sale to the consuming public, thereby making such weighted pool cover perimeter anchors economically available to the buying public.
Still yet another object of the present invention is to provide a new weighted pool cover perimeter anchor which provides in the apparatuses and methods of the prior art some of the advantages thereof, while simultaneously overcoming some of the disadvantages normally associated therewith.
Still another object of the present invention is to provide a new weighted pool cover perimeter anchor for securing a perimeter of a cover about a pool.
Yet another object of the present invention is to provide a new weighted pool cover perimeter anchor which includes an elongated anchor means positionable about a perimeter of a pool, and securing straps coupling the anchor means to the perimeter edge of a cover extending over the pool, whereby the anchor means includes a plurality of conduits which can be filled with water to increase a weight of the anchor assembly to a desired amount for securing the cover relative to the pool.
These together with other objects of the invention, along with the various features of novelty which characterize the invention, are pointed out with particularity in the claims annexed to and forming a part of this disclosure. For a better understanding of the invention, its operating advantages and the specific objects attained by its uses, reference should be had to the accompanying drawings and descriptive matter in which there is illustrated preferred embodiments of the invention.
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 wherein:
FIG. 1 is an isometric illustration of a weighted pool cover perimeter anchor according to the present invention in use.
FIG. 2 is an end elevation view thereof.
FIG. 3 is a top plan view of the weighted pool cover perimeter anchor.
FIG. 4 is a cross sectional view taken along line 4--4 of FIG. 3.
FIG. 5 is a cross sectional view taken along line 5--5 of FIG. 3.
DESCRIPTION OF THE PREFERRED EMBODIMENT
With reference now to the drawings, and in particular to FIGS. 1-5 thereof, a new weighted pool cover perimeter anchor embodying the principles and concepts of the present invention and generally designated by the reference numeral 10 will be described.
More specifically, it will be noted that the weighted pool cover perimeter anchor 10 comprises a substantially rectangular cover 12 for positioning over a pool 14 to preclude entrance of debris into the pool during periods of non-use thereof. An elongated anchor means 16 extends about a perimeter of the cover 12 for anchoring the cover relative to the pool 14. Securing means 18 are coupled to the cover 12 for removably coupling the cover to the elongated anchor means 16. A filling means 20 is coupled to and positioned in fluid communication with the elongated anchor means 16 for selectively permitting an introduction of fluid into the elongated anchor means to increase a weight of the anchor means as desired.
As best illustrated in FIGS. 2 through 5, it can be shown that the elongated anchor means 16 according to the present invention 10 comprises a plurality of elongated conduits 22 connected together in fluid communication by a plurality of connectors 24. The connectors 24 include straight connectors which couple adjacent elongated conduits 22 together in a substantially collinear orientation relative to one another, and angled connectors which couple adjacent conduits together in a substantially orthogonal orientation. By this structure, the elongated anchor means 16 is configured to extend about a perimeter of the cover 12 positioned over the pool 14.
As shown in FIG. 1, the securing means 18 according to the present invention 10 preferably comprises a plurality of straps 26 which are mounted to the cover 12 and extend about the elongated anchor means 16. The straps 26 thus extend about the elongated conduits 22 of the elongated anchor means 16 to couple back with the cover 12 through the use of unillustrated fastening means such as "VELCRO" hook and loop fastener, mechanical snaps, or the like. By this structure, the securing means 18 can be selectively released from the elongated anchor means 16 to permit use of the pool 14 and storage of the cover 12 as desired.
Referring now to FIG. 2, it can be shown that the filling means 20 according to the present invention 10 comprises a T-connector 28 positioned in fluid communication with at least one of the elongated conduits 22 of the elongated anchor means 16. The T-connector 28 of the filling means 20 includes a removable plug 30 permitting the introduction of water or other weighted fluids, such as an antifreeze mixture or the like, into the anchor means 16 to increase a weight thereof.
As shown in FIG. 5, one of the elongated conduits 22 of the anchor means 16 preferably includes a vent aperture 32 directed therethrough which cooperates with the filling means 20 to facilitate ease of injection of a weighted fluid thereinto. Preferably, a buoyant valve plate 34 is pivotally mounted to an interior surface of the elongated conduit 22 through which the vent aperture 32 is directed, thereby to close the vent aperture 32 upon a complete filling of fluid within the elongated anchor means 16.
As shown in FIG. 4, the connectors 24 according to the present invention 10 preferably each comprise a cylindrical member 36 positionable over the elongated conduits 22 of the anchor means 16. A mounting base 38 desirably extends from the cylindrical member 36 to terminate in a planar lower surface having an elastomeric pad 40 extending therealong for engagement with a surface adjacent to the pool 14. Preferably, the elastomeric pad 40 includes a plurality of engaging projections 42 and extending therefrom for enhancing frictional engagement between the elastomeric pad and the surface surrounding the pool 14. By this structure, the connectors 24 provide enhanced frictional engagement of the anchor means 16 relative to the surface surrounding the pool 14 to preclude a pulling of the cover 12 into the pool.
In use, the weighted pool cover perimeter anchor 10 according to the present invention can be easily utilized in combination with the cover 12 to effect securing of the cover about the perimeter of the pool 14 during periods of non-use of the pool.
As to a further discussion of the manner of usage and operation of the present invention, the same should be apparent from the above description. Accordingly, no further discussion relating to the manner of usage and operation will be provided.
With respect to the above description then, it is to be realized that the optimum dimensional relationships for the parts of the invention, to include variations in size, materials, shape, form, function and manner of operation, assembly and use, are deemed readily apparent and obvious to one skilled in the art, and all equivalent relationships to those illustrated in the drawings and described in the specification are intended to be encompassed by the present invention.
Therefore, the foregoing is considered as illustrative only of the principles of the invention. Further, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described, and accordingly, all suitable modifications and equivalents may be resorted to, falling within the scope of the invention. | An anchor for securing a perimeter of a cover about a pool. The inventive device includes an elongated anchor assembly positionable about a perimeter of the pool. Securing straps couple the anchor assembly to the perimeter edge of a cover extending over the pool. The anchor assembly is preferably formed of a plurality of conduits which can be filled with water to increase a weight of the anchor assembly to a desired amount. | 4 |
BACKGROUND OF THE INVENTION
The present invention relates to a vacuum pump apparatus, and, more particularly, to a non-lubricated vacuum pump apparatus which does not employ oil for cooling and lubrication in a working space and which is suitable for handling corrosive gas used in producing semiconductor devices or gas in which a reaction product is produced. The present invention also concerns a shaft sealing device for this pump apparatus.
When gas suctioned and exhausted by a vacuum pump is corrosive gas or noxious gas containing dust, or the like, a means is available for introducing inert gas into an internal housing in order to protect a drive apparatus such as a motor or a wiring therefor from being corroded by the gas, as disclosed in Japanese Patent Unexamined Publication No. 61-43298.
Meanwhile, in a vacuum pump, a working space is separated from a bearing chamber or a gear chamber by providing a non-contact type shaft sealing device, as disclosed in U.S. Pat. No. 4,714,418. Accordingly, measures are taken to reduce a pressure difference across the shaft seal so as to reduce the shaft sealing load.
In non-lubricated screw vacuum pumps, bearings supporting a male rotor and a female rotor are disposed on both sides of the rotors and a timing gear is provided for synchronizing the rotation of both rotors. Hence, it is necessary to prevent the oil which has lubricated these portions from entering the working space. If such a screw vacuum pump is used for an apparatus for producing semiconductors as a pump for handling corrosive gas or gas in which a reaction product is produced, it is necessary to take protective measures against the corrosion and reaction products in the shaft sealing device, the bearing chamber, and the gear chamber. Particularly, since the concentration of the gas is high in the gear chamber on the discharge side, the discharge side of the gear chamber is subjected to severe conditions as compared with the suction side thereof.
SUMMARY OF THE INVENTION
An object of the present invention is to provide a vacuum pump apparatus which is capable of effectively preventing lubricating oil for bearings for rotors from entering into a working space. Another object of the present invention is to provide a vacuum pump apparatus which is capable of preventing troubles caused by corrosion gas and adhesion of products due to reaction products and which is capable of reducing flow rate of seal gas introduced into a shaft sealing device.
In the present invention, a shaft seal portion on the discharge side is provided with a first floating seal member which is floatable with respect to a rotary shaft, a second floating seal member, and a gas introducing chamber formed between the first and second floating seal members. A seal gas supplying source is connected to this gas introducing chamber via a seal gas introduction line. In addition, the pressure of the gas introduced into the gas introducing chamber is controlled in such a manner that a pressure difference between the gas introducing chamber and the gear chamber is always set to a fixed value.
When the vacuum pump is started, the pressure in the suction port declines, and the rate of this decline is affected by the size of a vessel which is connected to the suction port, the rotational speed of rotors, and the like. Meanwhile, the mean pressure within each tooth space at an end surface of the discharge port is dependent on the pressure within the suction port, while a pressure P 1 between floating seal members that are adjacent thereto is dependent on the mean pressure within each tooth space at the end surface of the discharge port. Accordingly, to completely seal the shaft on the discharge side, the pressure between the first and second floating seal members, i.e., the pressure P 1 within the gas introducing chamber, and the pressure P 2 within the gear chamber must satisfy the formula P 1 >P 2 . A controller for controlling flow rate of seal gas is adapted to supply a signal for controlling opening degree of a control valve provided in, for instance, the gas introduction line and to allow the seal gas to be introduced from a gas introducing opening into the gas introducing chamber, thereby to control so that the pressure difference of P 1 -P 2 always becomes a constant positive pressure.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a vertical cross-sectional view of a vacuum screw pump apparatus, including a speed increasing gear, in accordance with an embodiment of the present invention;
FIG. 2 is a cross-sectional view taken along the line II--II in FIG. 1;
FIG. 3 is an enlarged cross-sectional view of a discharge-side shaft seal portion; and
FIG. 4 is a cross-sectional view taken along the line IV--IV in FIG. 3 in which a first floating seal member and a spring are omitted.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to the drawings wherein like reference numerals are used throughout the various views to designate like parts and, more particularly, to FIGS. 1 and 2, according to these figures, a vacuum screw pump includes a casing generally designated by the reference numeral 11 comprising a main casing 1, a discharge side casing 2 and an end cover 3, with a male rotor 4 and a female rotor 5 engageable with each other, being accommodated in the casing 11. The main and discharge-side casings 1, 2 define a working space 6 and the main casing 1 and the pair of rotors 4, 5 define a plurality of working chambers.
As shown in FIG. 1, a suction port 14, communicating with the working space 6, is formed in the main casing 1, while a discharge port 15 communicating with the working space 6 is formed in the discharge-side casing 2.
The male and female rotors 4, 5 are supported by roller bearings 7, 8 at their suction and discharge side rotor shafts and a male timing gear 9 and a female timing gear 10 are respectively fixed to the discharge side rotor shafts. The male and female rotors 4, 5 are meshed with each other with a small gap being maintained to be rotated.
In addition, shaft seal portions 51, 52 are respectively provided on both suction and discharge sides of the male rotor 4 and the female rotor 5. These shaft seal portions 51, 52 are adapted to effect sealing so that the lubricating oil used for the roller bearings 7, 8, the timing gears 9, 10 and the like will not leak into the working space 6.
An oil scraping slinger 12 is installed at a tip of the rotor shaft (in this example, on the rotor shaft of the female rotor 5). This slinger 12 is used to supply the lubricating oil to the roller bearings 7 by splashing the lubricating oil in an oil reservoir 13 of a bearing chamber 33 formed by a part of the main casing 1 and the end cover 3. The male timing gear 9 is engaged with a bull gear 9', as shown in FIG. 1, and the bull gear 9' is coupled with an electric motor (not shown) via a drive shaft 17.
A gear chamber 18 is adapted to accommodate a gear system for driving the rotors 4,5, and is hermetically sealed by a gear casing 19, a side plate 20 and a shaft seal member 21. The discharge side casing 2 includes a bearing chamber for the roller bearings 8.
An oiling port 22 is formed in the gear chamber casing 19 and is adapted to supply the lubricating oil to the roller bearings 8, the male timing gear 9, the female timing gear 10, and the bull gear 9' by means of an oiling pump (not shown) provided separately.
As shown most clearly in FIGS. 3 and 4, the first and second floating seal members 53, 54 are provided in a position of the shaft seal portion 52 which is nearer to the rotors, that is, to the working space 6 and disposed between a step portion 61 formed on the discharge-side casing 2 and a spacer 62 provided in the shaft seal portion 52. A labyrinth seal member 55 is provided in a position of the shaft seal portion 52 which is nearer to the roller bearing 8 and disposed between the spacer 62 and a retaining ring 63 for determining the axial position of the labyrinth seal member 55. A threaded seal member 56 is disposed between the first and second floating members 53, 54 and the labyrinth seal member 55 and is adapted to produce a pressure acting from the working space 6 toward the gear chamber 18.
A gas introducing chamber 57 is formed between the first floating seal member 53 and the second floating seal member 54. A spring 58 is provided in this gas introducing chamber 57 and between the first floating seal member 53 and the second floating seal member 54. In addition, a spring 59 is interposed between an end surface portion of the threaded seal member 56 and an end surface portion of the labyrinth seal member 55.
An O-ring 64, interposed between the labyrinth seal member 55 and the spacer 62, is adapted to prevent the leakage of oil from a gap between the labyrinth seal member 55 and the discharge-side casing 2.
A gas introduction hole 39, provided in the discharge-side casing 2, and a pressure detecting hole 41 for detection of the pressure are communicated with the gas introducing chamber 57. A seal gas supplying source (not shown) is communicated with this gas introduction hole 39 via an introduction line 42. Flow rate of the seal gas introduced into the gas introducing chamber 57 is controlled by a control valve 43 provided in the introduction line 42.
A controller 44 is adapted to control opening degree of the control valve 43. This controller 44 compares the pressure P 2 of the gear chamber 18 supplied from a pressure fetching hole 40 for detecting the pressure in the gear chamber 18, which is provided in the gear casing 19, with pressure P 1 of the gas introducing chamber 57 supplied from the aforementioned pressure detecting hole 41, and outputs a control signal in such a manner that pressure difference of P 1 -P 2 always becomes a fixed positive value. A blow pipe 38 for preventing a pressure rising inside the gear chamber 18 during an operation is provided between the gear casing 19 and a discharge pipe 36. An oil trap 37 for separating and recovering the oil in the gas is provided in this blow pipe 38.
The shaft sealing means of the suction-side shaft seal portion 51 is arranged in the same way as the discharge-side shaft seal portion 52 shown in FIG. 3, except for the gas introduction hole 39 and pressure detecting hole 41, but is provided with a pipe for eliminating a pressure difference across the shaft seal portion 51. Namely, in FIG. 1, a uniform pressure pipe 35 communicates between the suction port 14 and the bearing chamber 33, and is provided with an oil trap 34 for separating the oil contained in the gas.
In a stopped condition, the suction port 14, working space 6, discharge port 15, bearing chamber 33, and gear chamber 18 are all under atmospheric pressure. In this state, when the vacuum pump is started, as the one of working chambers moves from the side of the suction port 14 toward the side of the discharge port 15, the pressure on the side of the suction port 14 falls gradually, and the distribution of the pressure inside the working space 6 becomes such that the pressure becomes lower from the suction ends toward the discharge ends of the rotors. Since the bearing chamber 33 is communicated with the suction port 14 by means of the uniform pressure pipe 35, the pressure difference across the suction-side shaft seal portion 51 becomes virtually negligible. In addition, by virtue of the action of the labyrinth seal member 55 and the threaded seal member 56, the oil which has lubricated the roller bearings 7 is prevented from leaking into the working space 6.
Meanwhile, with respect to the discharge-side shaft seal portion 52, since the mean pressure in each tooth space at the end surfaces of the rotors declines in accordance with the decline in the pressure inside the suction port 14, the pressure between the first floating seal member 53 and the second floating seal member 54 that are disposed adjacent to the end surfaces of the rotors also falls. Subsequently, the pressure P 1 between the first floating seal member 53 and the second floating seal member 54, that is, in the gas introducing chamber 57 becomes imbalanced with the pressure P 2 inside the gear chamber 18, and a signal for adjusting the opening degree of the valve 43 is issued from the controller 44 to the control valve 43. As a result, the seal gas is introduced between the first floating seal member 53 and the second floating seal member 54, that is, in the gas introducing chamber 57, thereby making it possible to maintain the state of P 1 >P 2 . Therefore, lubricating oil is prevented from entering the working space 6. Further, as the pressure P 1 in the gas introducing chamber 57 becomes higher than the working space 6, a part of the seal gas can flow into the working space 6, so that gas suctioned by the vacuum pump is prevented from entering the working space 6.
According to the present invention, a vacuum pump apparatus is provided which is capable of effectively preventing the lubricating oil for bearings from entering the working space and which is capable of preventing troubles caused by the corrosion gas and adhesion of the reaction products.
In the foregoing embodiment, although a description has been given of a non-lubricated vacuum screw pump, a similar effect can be obtained even in the case of other types of vacuum pump apparatus in which oil is not present in the working space, but lubricating oil for the bearing portion is used, and which is operated when the pressure within the working space is lower than that within the bearing portion. Such alternative vacuum pump apparatus include, for example, a movable wing- or Root-type vacuum pump apparatus and an axial flow-type or centrifugal-type vacuum pump apparatus. | A vacuum pump apparatus comprises a male and female screw rotors meshing with each other, a casing for accommodating the male and female screw rotors and having a working space, a suction port and a discharge port both communicating with the working space, bearing portions for supporting shafts of the male and female screw rotors on the suction and discharge sides thereof. Shaft seal portions which are respectively disposed between the working space and each of the bearing portions and are adapted to seal the shafts of the male and female screw rotors on the suction and discharge sides thereof. Seal gas introducing device introduces seal gas into the shaft seal portions, and a controller controls the pressure of the seal gas introduced into the shaft seal portions. | 8 |
RELATED APPLICATION
This application is a division of my co-pending application Ser. No. 870,330 filed Jan. 18, 1978 and entitled "Method and Means for Improving the Spectrum Utilization of Multi-Channel Telephone Systems". It is also related to my co-pending application filed July 18, 1977, Ser. No. 816,661 entitled, "Method and Means for Improving the Spectrum Utilization of Communications Channels".
BACKGROUND OF THE INVENTION
While features of the invention are subject to a wide range of applications, the invention is especially suited for use in TASI (Time Assignment Speech Interpolation) systems and will be particularly described in that connection.
TASI systems have been used to improve the utilization efficiency of voice communications systems by reducing the time that telephone lines are temporarily idle. For example, in a conventional two-way telephone circuit, over 50% of the line's capacity is wasted, accommodating the listener's transmit channel.
The TASI system constantly monitors speech channels and quickly reassigns lines from idle channels to active channels increasing the overall efficiency of the system. TASI systems have been described in the literature; for example, K. Bullington and J. M. Fraser, "Engineering Aspects of TASI", BSTJ, Vol. XXXVIII, March 1959, and "Transmission Systems for Communications", Bell Telephone Laboratories, 1970, pages 682 to 684 including references.
In the conventional TASI system, separate line(s) are used for transmitting channel assignment information, although systems have been described wherein the initial channel assignment information is transmitted via the line assigned to transmit the channel.
It is noteworthy that the telephone communications network systems utilize a multiplicity of transmission systems; including, wire line, wideband cables, Satellite links, microwave radio links, etc., and that the time delay characteristics of these transmission systems substantially differ. Such significant differences in delay can cause degraded control performance of a TASI system when, say, long time delay lines are used in transmitting control information of short time delay lines. Also, failure of a line transmitting control information can cause a large number of circuits to improperly perform. Thus, a conventional TASI system may be subject to poor operation and simultaneous interruption of a number of conversations if it utilizes a common control line.
If TASI systems utilize the assigned line to transmit the initial channel assignment information, the problem of a difference in time delay between the line carrying the voice signal and the line carrying the control information is eliminated except for poor timing of the line disconnect system. Also, since conventional TASI systems transmit information regarding channel assignment status and idle line status over a separate line, these systems are subject to performance degradation when the control line becomes inoperative. Of course, spare lines can be provided, but at a loss in line utilization efficiency. Furthermore, if a line carrying a telephone signal fails in such systems, a conversation is interrupted until the call is reassigned.
SUMMARY OF THE INVENTION
A general object of the instant invention is to provide means for improving the spectrum utilization of communications channels.
A further object is to improve the operating efficiency of a TASI type system. Another object of the invention is to allow the use of a mixture of telephone lines having appreciably different time delay characteristics to be used in a TASI type system. Also, this invention allows TASI systems to be used with two wire lines.
A further object of the instant invention is to improve the reliability of the control circuit sensitivity of a TASI type system. A still further object is to provide a system that may be constantly monitored and cause inoperative lines to be automatically removed from operation and alarm circuitry automatically activated.
The present invention provides improved telephone line utilization efficiency for multi-channel telephone systems and in one embodiment utilizes the following method steps:
1. Sensing the speech activity of a telephone channel.
2. Selecting a line from a group of inactive lines for transmitting the speech wave sensed in Step (1), and subsequently connecting the speech wave to the selected line.
3. Rapidly transmitting (in approximately 10 milliseconds) the initial channel identification information over substantially the entire bandwidth of the selected line to the remote end of the line; and,
4. Transmitting continuous channel verification information in a narrowband slot in the passband of the line concurrently with the transmission of the speech wave.
In one embodiment of the invention the narrowband slot of Step (4) has a bandwidth of approximately 300 Hz and one preferred arrangement would be to have the slot fall between approximately 2,000 and 2,300 Hz.
For a better understanding of the present invention, together with other and further objects thereof, reference is had to the following description, taken in connection with the accompanying drawings, while its scope will be pointed out in the claims.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows a block diagram of one embodiment of the invention.
FIG. 2 shows, in block and schematic form, the talk or transmit end of the invention.
FIG. 3 shows, in block and schematic form, the listen or receive circuitry of the invention.
FIG. 4 is a more detailed block diagram of a frequency inverter shown in FIGS. 2 and 3.
DESCRIPTION OF THE PREFERRED EMBODIMENT
FIG. 1 shows a simplified block diagram of one end of a system using an embodiment of the invention.
The T line, or talk line, feeds block 100 (A) the Channel A transmitter. Each channel transmitter incorporates circuitry for locating an unused transmit line, switching circuitry for connecting the channel to any one of the available lines and a channel identification wave generator. Details of the channel transmitter circuitry are shown in FIG. 2, and description of this equipment, as well as the idle signal generator circuitry, is provided below.
The output lines of the channel transmitters are connected through summation circuits, not shown, to line hybrid circuits which are used for isolating the talk and listen signals when two wire lines are used. Hybrid transformers are commonly used for providing such isolation. Unfortunately, it is difficult to achieve and maintain high degrees of isolation. For detailed discussions of hybrid circuits, two wire and four wire lines, one can consult a number of publications dealing with telephony, including the above cited book "Transmission System for Communications", written and published by Bell Telephone Laboratories, 4th Edition, 1970.
In order to reduce the deleterious effects of crosstalk caused by imperfect hybrid circuits or other imperfections, it is desirable to use the invention disclosed in my co-pending patent application Ser. No. 870,330. Accordingly, the transmitter at one end of the circuit may be equipped with encoding devices such as a frequency inversion system, and at the other end a compensating frequency inversion system is incorporated into the receiver.
Each of the n lines feeds a line receiver which includes means for decoding the m channel (m is greater than n) identification waves and using the decoded information to switch the received speech wave to the assigned channel. Also included in the receiver is circuitry for activating an alarm if the line fails. FIG. 3, as described below, shows details of the line receiver.
Also shown in FIG. 1 is the line activity indicating multi-wire bus 101 which provides information to the various channel transmitters allowing the transmitter to make proper line assignments.
As shown in FIG. 1, hybrid circuit 300(1) feeds the line receiver, and isolates the receive signal from Channel A transmit signal.
FIG. 2 shows one type of transmitter suitable for implementation of this invention. The Channel A T, talk circuit, feeds speech presence detector 104A. This speech detector may utilize various type circuits, including the type disclosed in U.S. Pat. No. 3,337,808. The control voltage produced by speech detector 104A feeds stepper control circuit 116A. On the initiation of a speech presence indication from 104A, stepper control 116A causes switches 118A and 120A to start stepping from one switch position to another until an idle talk line is located.
One possible procedure for locating an idle line is shown in FIG. 2. Switch 120A, as well as 118A, is preferably an electronic switching circuit and may use integrated circuit gates. For simplicity of explanation, a mechanical type switching circuit is shown. Actually, some equipment designers may prefer to use mechanical switches. However, for rapid operation, electronic switches are preferred. Each contact of the switch assigned to a line is connected through a resistor to +E volt point. For example, the contact representing line 1 is connected to +E through resistor 10, and the contact representing line 2 is connected to +E through resistor 20, etc.
The arm of the switch is returned to ground through resistor 122A. It should be noted that the resistors 10, 20, 30, etc. are connected in common with all of the channel transmitter's switches 120A to N. Therefore, if line 1 is in use, the channel using line 1 connects its resistor 122 to resistor 10, reducing the voltage appearing at the contact side of resistor 10. This reduced voltage is sensed at all channel 120 switches, causing any stepper circuit in operation to continue to step past the line 1 position. When, say, 120A switch is caused to step to the line 2 position, which, for example, is idle in the talk direction, the voltage sensed across resistor 122A would be substantially higher than when switch 120A was in the line 1 position. For example, if resistors 10, 20, 30, etc., are 10,000 ohm resistors, and 122A to N are 1,000 ohm resistors, and +E is 10V, there would be 0.909 volts across resistor 122A in the line 2 position, and 0.476 volts across resistor 122A in the line 1 position.
These differences in voltage allow the stepper circuit to stop the line switch in the first inactive position. In addition, the voltage differences control the transmission of the idle signal over the temporarily idle lines.
The line associated 120 contacts are connected together by line activity indication bus 101.
Stepper control circuit 116A also controls the signal switching circuit 118A. Accordingly, if switch 120A stops at line 1, so does switch 118A connecting the signal circuit to line 1. The voice signal from Channel A talk circuit is processed as follows:
The voice wave appearing on the Channel A T line, besides feeding the speech presence detector 104A, feeds time delay circuit 102A. This circuit delays the speech wave so as to allow some time for the channel assignment circuitry to operate at the far end of the circuit. A time delay in the order of 10 to 20 ms would be required for typical installations.
For these values of time delays, the equipment designer has the choice of using mechanical magnetic tape time delay loops or solid state time delay circuits. For high reliability performance, solid state charge coupled integrated circuits are a good choice. Such devices as the SAD-1024 analog delay line as manufactured by the Reticon Corporation of Sunnyvale, California, are available for such applications.
The time delay circuit serves two purposes.
(a) It delays the voice signal so that little or no initial speech sounds are lost after speech presence is detected and while the channel/line assignment is being established and,
(b) It avoids the transmission of spech during the transmission of the high speed channel identification signal, reducing the probability of errors in connecting lines to the proper channel utilization circuit.
It is possible to delete the time delay circuit, but, in this case, a gating circuit should be provided in order to gate the speech wave off during the transmission of the initial identification signal so as to avoid causing channel switching errors. Also, if time delay circuits are not provided, a finite clipping of initial voice signals will be suffered.
The output of time delay circuit 102A is amplified, if necessary, in amplifier 108A, which, in turn, feeds band reject filter 110A. This filter cuts a narrow slot in the passband of the voice signal in order to provide spectrum space for the narrowband channel identification signal. In a prior patent, U.S. Pat. No. 3,684,838, it was disclosed that a cut of 200 or 300 Hz at preferably the mid-upper range of the telephone transmission channel did not materially degrade quality or intelligibility of speech waves. For example, a band reject filter which substantially attenuates speech components between 2,000 and 2,300 Hz would be suitable for this application. The output of filter 110A feeds summation circuit 112A. Also feeding summation circuit 112A is Channel A code generator 106A. This generator produces two types of identification waves:
(a) a high speed channel identification wave which may use substantially the entire line's bandwidth, typically between 400 and 2,700 Hz, and
(b) a narrowband channel identification wave which must fall within the slot produced by band reject filter 110A; for example, 2,050 to 2,250 Hz.
As to the type of identification wave used, the designer may use any of the numerous signalling methods, such as on/off keying, frequency shift keying, and phase shift keying.
Such systems are detailed in numerous publications; for example, W. R. Bennett and J. R. Davey, "Data Transmission", McGraw-Hill, New York, 1965. The code generator, when initially sensing speech presence from the control voltage produced by speech presence detector 104A, produces a high speed Channel A identification signal. This signal would require approximately 10 ms for transmission and would start some 2 ms after speech is detected by detector 104A. The 2 ms interval is provided to allow the idle line locator to select an idle line.
There are numerous code generators available to the designer. For example, the book "Digital Integrated Electronics", H. Taub and D. Schilling, McGraw-Hill, New York, 1977, in Chapter 10, discusses equipment useful for such purposes and also provides design information.
It is possible to use a single code for both the high speed and narrowband channel identification waves and merely slow down the readout speed by reducing the clock frequency when transmitting the narrowband wave. It is desirable to simultaneously shift the carrier frequency of the keyed wave to be sure to center the keyed wave in the passband of the narrowband filter when transmitting the narrowband identification wave from a frequency centered in the line passband for the high speed transmission.
When the transmission of the high speed channel identification signal is completed, the Channel A code generator initiates transmission of the narrowband Channel A identification wave, which continues until the speech detector 104A indicates that the local A speech channel has been idle, for, say, 300 ms. At that time the associated line is disconnected from Channel A and generator 106(A) can cease operation.
When Channel A talk circuit is idle, line 2 should, during high traffic activity conditions, be freed for service with other channels. The disconnecting of line 2 from Channel A is accomplished as follows:
The speech presence detector 104A will produce a no signal indication voltage which will, after, for example, 200 to 300 ms, cause stepper control circuit 116A to control switching circuits 118A and 120A to switch to their idle positions. Thus, Channel A is disconnected from line 2.
It is advantageous that means be provided for monitoring the availability of lines at all times. Accordingly, additional circuitry is provided for transmitting an idle code signal whenever a line is unassigned.
This continuous protection is provided by using the rise in voltage whenever all of the arms of the various 120 switching circuits are disconnected from the line activity sensing resistors 10, 20, 30, etc. to control associated gates. For example, if line 2 becomes inactive, the voltage at the switch contact end of resistor 20 rises. This increased voltage is sufficient to close gate 50 passing the idle code wave generated in generator 60 to summation circuit 80. When line 1 is idle, the idle wave passes through gate 40 to summation circuit 70. Thus, means are provided to insure constant monitoring of the lines' condition. The idle signal may have characteristics similar to the narrowband channel identification waves.
The output of summation circuit 112A is amplified in amplifier 114A. The output of amplifier 114A is fed to a conventional frequency inverter circuit 126A for transmitters at one end only of the system. The frequency inversion converts high audio frequency components to low frequency and vice-versa. Thus, by this procedure, which is claimed in my application Ser. No. 870,330, crosstalk signals are made unintelligible. By this procedure, the "talk" waves going in one direction are unintelligible to local "listen" paths. Also, as will be discussed in the section treating FIG. 3, the receiver inverts the desired receive speech wave and, accordingly, causes any local talk crosstalk speech sounds due to the hybrid circuit unbalance to be unintelligible. Since unintelligible crosstalk is normally less disturbing to conversations and avoids the possibility of overhearing conversations, this is a major feature of the invention disclosed in patent application Ser. No. 870,330.
It should be noted that since the frequency inversion system is a complementary transformation, it is important that frequency inversion should be used in the talk circuit at only one end of the system. For example, if, in an East/West system, the talk frequency inversion is provided for the East talk circuit, none should be provided in the West talk circuit and frequency inversion be applied only to the West receive circuit.
Details of one type of frequency inversion circuit are discussed below in the description of FIG. 4 and in patent application Ser. No. 870,330. Switch 124(A) should be open in the East location, and closed, disabling inverter 126(A), in the West location.
The output of inverter 126A or switch 124A feeds line switching circuit 118A to the selected line's hybrid circuit, causing Channel A speech wave to be transmitted to the far end of the circuit. The other channel waves are processed in the same manner by their channel transmitters.
If a gate is used in lieu of time delay circuit 102A, or if an insufficient length delay circuit is used, the gate circuit can be controlled by speech detector circuit 104A or by an idle contact of switch 120A.
FIG. 3 shows the details of the receive or listen equipment. As is true of the transmit circuits, two receive circuits are assigned to each line used; one at, say, the East end, and one to the West end. The basic task of the receive unit is to decode the transmitted channel/line assignment coded wave and accordingly switch each line to its assigned channel. Another basic function of the receivers at one end of the system is to frequency invert the previously inverted speech wave to restore intelligibility. Another important task of one preferred receiver embodiment is to continuously monitor the availability of the lines so as to cause prompt alarm activation if a line becomes unavailable.
Referring to FIG. 3, the receive port of the line 1 hybrid circuit feeds bandpass filter 204(I) through the arm of relay 202(1). The relay is shown in the position proper for reception of either a narrowband channel identification wave or an idle channel signal. The output of filter 204(1) selects the narrow signal wave in the range of, for example, say, 2,000 to 2,300 Hz, and attenuates the speech components falling below 2,000 Hz and above 2,300 Hz. Filter 204(1) feeds channel signal detector 206(1). The channel signal detector decodes the channel assignment signals and provides a control signal for the switching circuit 214(1). Switch 214(1) connects the received voice wave from line 1 to the assigned channel. The example illustrated in FIG. 3 is that of line 1 connected to Channel B.
Also connected to the output of filter 204(1) is idle signal detector 208(1). When the idle signal detector receives an idle signal two effects are caused to occur. First, switch 214(1) disconnects line 1 from whatever channel it had been connected to and switches the signal path to the idle or off position. And the second effect is the operation of relay circuit 202(1) which switches the signal input from filter 204(1) to directly feed channel signal detector 206(1). Thus, the channel signal detector is fed the entire incoming channel bandwidth rather than a small frequency segment.
Accordingly, the receiver is ready to receive a wideband, high speed channel identification signal.
Thus, the receiver is designed to recognize the presence of three types of control signals; i.e.,
(a) the high speed channel assignment signal,
(b) the narrowband channel assignment signal, and
(c) the idle signal.
Since at least one of the above signals is always transmitted, absence of all of them activates line failure detector 210(1), which in turn energizies an alarm circuit. The line failure circuit, instead of detecting the 3 signals directly, may be connected to detectors 206(1) and 208(1), in order to determine if a control signal is present.
It should be noted that in addition to its use in the line failure indication system, the narrowband channel assignment signal allows the line to switch to the desired channel when there is an error in transmission of the high speed channel assignment signal. While such an error will cause the loss of some of the speech wave, the channel will be eventually connected. For a typical narrowband signal, instead of 10 ms, it will take approximately 100 ms to establish the circuit.
The input line also feeds a frequency inverter, which is used to restore intelligibility of inverted speech waves.
If the receiver is located at the end of the circuit not requiring frequency inversion, switch 218(1) is switched to the bypass position, disabling the frequency inversion. The speech wave is then passed through a band reject filter (212(1) which substantially removes the channel assignment coded signal wave from the speech wave which fall, for example, between 2,000 to 2,300 Hz. The output of filter 212(1) feeds resulting speech wave to the channel switching circuit 214(1) which in turn feeds the speech wave to the assigned channel.
FIG. 4 shows one example of encoding talk signals by frequency inversion as shown in block 126.
This same circuit may be used at the other end of the system for decoding the signal by complementary frequency inversion as shown in block 216.
The speech wave is amplified in amplifier 402 which may be required to provide a more suitable level of impedance. The output of amplifier 402 feeds Balanced Modulator A 404. Also feeding Balanced Modulator 404 is Oscillator A block 406. The operating frequency of Oscillator A is selected so that one of the sidebands of the double-sideband wave produced in Modulator 404 falls in the passband of single-sideband filter 408. As an example, the oscillator can be set to 100 kHz, and for good stability should be of the crystal controlled type.
Thus, the output of Balanced Modulator A 404 is a double-sideband suppressed carrier wave centered at 100 kHz. This wave is fed to SSB filter 408, which substantially attenuates, say, the lower sideband and passes the resulting upper-sideband SSB wave to balanced modulator B 410. Balanced Modulator B is also fed by Oscillator B 412. Oscillator B operates at higher frequency in this situation, because the USB is used. A suitable frequency would be 103.3 kHz if speech waves covering 300 to 3,000 Hz are to be transmitted through lines capable of passing 300 to 3,000 Hz. The output of the Balanced Modulator would then be passed through LPF 416 so as to attenuate undesired mixing products and the 100 kHz wave. In many instances, the LPF 416 can be deleted, and other circuits, such as amplifiers and transformers with limited frequency responses, can be used to provide the filtering action.
The system of FIG. 4 will translate 300 Hz waves to 3,000 Hz, 1,000 Hz waves to 2,300 Hz, and 3,000 Hz waves to 300 Hz. At the far end of the circuit, the complementary operation is performed, restoring the frequency of the speech components within the relative accuracy of the oscillator used in the system.
It will be apparent to those skilled in the applicable art that a phase shift type SSB system may be substituted in the system of FIG. 4 for the filter system shown.
In all cases, it is understood that the above described arrangements are merely illustrative of the many possible specific embodiments which represent applications of the present invention. Various changes and modifications can be readily devised in accordance with the principles of the present invention without departing from the spirit of the invention and within the scope of the following claim. | A system and method for improving the spectrum utilization of voice communications channels by increasing the number of voice conversations a given number of lines can service. This invention can be used to improve the reliability and efficiency of conventional TASI (Time Assignment Speech Interpolation) systems and allow such systems to provide good performance when utilizing a mixture of types of telephone lines; including, microwave, cable, satellite, and two wire configuration lines. | 7 |
FIELD
The present disclosure relates to a structure to aid in orientation and retention of a fuel injector to a fuel rail.
BACKGROUND
This section provides background information related to the present disclosure which is not necessarily prior art. Internal combustion engines such as direct injection engines may employ fuel injectors that provide a fluid conduit between a pressurized fuel rail and a combustion cylinder of an internal combustion engine. While current fuel injectors and corresponding fuel rails have been satisfactory for their given applications, such components are not without need for improvement.
Engine assemblers desire a tight, secure and aligned assembly of the fuel injector to the fuel rail to prevent disassembly during part shipment and during installation of the fuel rail and fuel injectors onto the engine. Additionally, prevention of a fuel injector from becoming misaligned with the fuel rail during assembly onto an engine or prior to assembly onto an engine or during engine operation is also desired. Typically, a fuel rail will employ a fuel injector cup that is brazed, welded or otherwise secured to a fuel rail. An injector may reside within the injector cup with the aid of a compressed O-ring, which resides over the injector inlet. During shipment of fuel injectors or during assembly of a fuel rail and an injector combination onto an engine, because only an O-ring is compressed against an interior of the injector cup, the integrity of the holding force of the compressed O-ring may be compromised, resulting in parting of the injector from the injector cup or misalignment of the parts prior to installation onto an engine. Moreover, during operation, fuel injectors may become stuck or seized onto the engine cylinder head due to soot or carbon build-up at the tip of the injector. In such a case, it is desirable to have the rail and injector separate easily. Thus, during servicing of a fuel injection system, service technicians desire a relatively quick disconnect of the fuel injector from adjacent components.
What is needed then is a device that quickly permits alignment and secure connection of a fuel injector with an injector cup and injector rail but that also permits quick and easy separation of the fuel injector from an injector cup.
SUMMARY
This section provides a general summary of the disclosure, and is not a comprehensive disclosure of its full scope or all of its features. An apparatus to secure a fuel injector to an engine's common fuel rail may employ a fuel injector, a fuel injector cup, and an orientation tab integral with the fuel injector. The tab may attach to the fuel injector cup to secure the fuel injector to the fuel injector cup, which is brazed or welded to the common fuel rail. The fuel injector cup may further define a flange that defines a notch with the tab protruding through the notch to secure the fuel injector to the fuel injector cup. Upon securing the tab, the fuel injector also becomes aligned with the fuel rail, which may be attached to the fuel injector cup. The tab may employ a flexible first prong and a flexible second prong such that the first prong and the second prong protrude through the notch to secure the tab to the flange. The first prong and the second prong define a gap therebetween. The first prong may further exhibit a first prong interior straight wall surface that faces the gap and the second prong may further exhibit a second prong interior straight wall surface that faces the gap. The first prong interior straight wall surface and the second prong interior straight wall surface may be parallel. The first prong may also exhibit a first entry contact surface and a first exit contact surface that meet to form an apex, and the second prong may further exhibit a second entry contact surface and a second exit contact surface that meet to form an apex.
The tab may define a solid head portion below the gap, the solid head portion may be bounded by a first outside wall with a surface and a second outside wall with a surface; the surfaces may be parallel. The solid head portion may reside in the notch such that only a solid portion of head portion resides in the notch; this eliminates flexing of the head and prongs when bounding parallel walls of the solid head portion contact structure defining the notch. The first entry contact surface and the first prong interior straight wall surface form a first angle that is less than a second angle formed by the first exit contact surface (extended) and the first sidewall surface of the first outside wall.
Further areas of applicability will become apparent from the description provided herein. The description and specific examples in this summary are intended for purposes of illustration only and are not intended to limit the scope of the present disclosure.
DRAWINGS
The drawings described herein are for illustrative purposes only of selected embodiments and not all possible implementations, and are not intended to limit the scope of the present disclosure.
FIG. 1 is a side view of a vehicle depicting, in phantom, portions of a fuel system;
FIG. 2 is a schematic of a vehicle fuel supply system depicting fuel injectors, a fuel injection pump and a fuel pump module within a fuel tank;
FIG. 3 is a perspective view of a fuel injector, a fuel injector cup, a fuel injector spring tab, and a fuel injector alignment tab in accordance with the present disclosure;
FIG. 4 is a side view of a fuel injector, a fuel injector cup, a fuel injector spring tab, and a fuel injector alignment tab in accordance with the present disclosure;
FIG. 5 is a side view of a fuel injector with a fuel injector tab in accordance with the present disclosure;
FIG. 6 is a side view of the fuel injector cup in accordance with the present disclosure;
FIG. 7 is a top view of the fuel injector cup in accordance with the present disclosure;
FIG. 8 is a is a cross-sectional view of the fuel injector alignment tab in accordance with the present disclosure;
FIG. 9 is a side view of the fuel injector with a fuel injector alignment tab in accordance with the present disclosure;
FIG. 10 is a cross sectional view of the fuel injector, fuel injector cup and fuel injector alignment tab in accordance with the present disclosure;
FIG. 11 is a cross sectional view of the fuel injector alignment tab relative to the fuel injector cup;
FIG. 12 is a cross sectional view of the fuel injector, fuel injector cup and fuel injector alignment tab in accordance with the present disclosure;
FIG. 13 is a cross sectional view of the fuel injector alignment tab relative to the fuel injector cup;
FIG. 14 is a cross sectional view of the fuel injector, fuel injector cup and fuel injector alignment tab in accordance with the present disclosure;
FIG. 15 is a cross sectional view of the fuel injector alignment tab relative to the fuel injector cup;
FIG. 16 is a cross sectional view of the fuel injector, fuel injector cup and fuel injector alignment tab in accordance with the present disclosure; and
FIG. 17 is a cross sectional view of the fuel injector alignment tab relative to the fuel injector cup.
Corresponding reference numerals indicate corresponding parts throughout the several views of the drawings.
DETAILED DESCRIPTION
Example embodiments will now be described more fully with reference to the accompanying drawings. The following description is merely exemplary in nature and is not intended to limit the present disclosure, application, or uses. When an element or layer is referred to as being “on”, “engaged to”, “connected to” or “coupled to” another element or layer, it may be directly on, engaged, connected or coupled to the other element or layer, or intervening elements or layers may be present. In contrast, when an element is referred to as being “directly on,” “directly engaged to”, “directly connected to” or “directly coupled to” another element or layer, there may be no intervening elements or layers present. Other words used to describe the relationship between elements should be interpreted in a like fashion (e.g., “between” versus “directly between,” “adjacent” versus “directly adjacent,” etc.). As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items.
Spatially relative terms, such as “inner,” “outer,” “beneath”, “below”, “lower”, “above”, “upper” and the like, may be used herein for ease of description to describe one element or feature's relationship to another element(s) or feature(s) as illustrated in the figures. Spatially relative terms may be intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures is turned over, elements described as “below” or “beneath” other elements or features would then be oriented “above” the other elements or features. Thus, the example term “below” can encompass both an orientation of above and below. The device may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.
With reference to FIGS. 1-17 , a device that retains a fuel injector to a fuel injector cup and aligns a fuel injector to a fuel rail will be disclosed. FIG. 1 depicts a vehicle 10 , such as an automobile, having an engine 12 , a fuel supply line 14 , a fuel tank 16 , and a fuel pump module 18 . Fuel pump module 18 resides within fuel tank 16 and may be submerged in or surrounded by varying volumes of liquid fuel when fuel tank 16 possesses liquid fuel. For purposes of explanation of the present disclosure, the liquid fuel may be considered gasoline since the present disclosure will be explained in the context of a fuel supply system 20 that employs a fuel injection pump 22 , which may be employed to pressurize fuel rail 24 of engine 12 . However, it is to be understood that the present disclosure may be adaptable to a vehicle employing diesel, or other liquid fuel. Fuel pump module 18 may be employed to supply liquid fuel to engine 12 through fuel supply line 14 . FIG. 2 depicts fuel supply system 20 in which one or more fuel injectors 26 may be installed in engine 12 to receive fuel from a fuel injector common rail 24 . Fuel supply system 20 may be either a return or a returnless fuel system. To reach a fuel pressure that is high enough to increase the efficiency of combustion, fuel may be pressurized by a fuel injection pump 22 before fuel reaches common rail 24 . To ensure that fuel is clean enough to pass through fuel injection pump 22 and then fuel injectors 26 , fuel may pass through a fuel filter 28 resident in fuel supply line 14 .
Before continuing with a description of the present teachings, the primary focus will be on a single fuel injector, a single fuel injector cup, and a single fuel injector alignment tab because each fuel injector 26 in an engine 12 with multiple fuel injectors 26 may have the same arrangement or structure. Turning now to FIG. 3 , an enlarged perspective view of fuel injector 26 is depicted along with an injector cup.
Continuing, FIGS. 3 and 4 depict a side view of a fuel injector assembly 30 , which may include fuel injector 26 , a fuel injector spring tab 32 , a fuel injector alignment tab 34 and a fuel injector cup 36 . An electrical plug 38 is a part of fuel injector 26 and provides a location where an electrical connection from a vehicle wiring harness interfaces with fuel injector 26 . As depicted, fuel injector spring tab 32 may have a first spring prong 40 and a second spring prong 42 that each reside around a side of fuel injector 26 . Spring prongs 40 , 42 are flexible and move in an upward and downward motion that is parallel to an axis of fuel injector 26 . First spring prong 40 has a first top surface 44 while second spring prong 42 has a second top surface 46 such that top surfaces 44 , 46 provide a surface for fuel injector cup 36 or a flange 68 of fuel injector cup 36 to contact and bias prongs 40 , 42 . A spring tab base 48 also has a first base prong 50 and a second base prong 52 that reside on opposing sides of fuel injector 26 to clamp to fuel injector 26 and form a press fit or interference fit with fuel injector 26 .
Turning to FIG. 5 , fuel injector 26 is depicted equipped with fuel injector alignment tab 34 , parallel to a longitudinal axis 70 of fuel injector 26 . Secured over injector inlet 56 of fuel injector 26 is an O-ring 58 . Before proceeding with additional structural details of fuel injector assembly 30 , potential construction materials of the various parts of fuel injector assembly 30 will be discussed. Fuel injector 26 , fuel injector spring tab 32 and fuel injector cup 36 may be made of stainless steel, while electrical plug 38 and fuel injector alignment tab 34 may be made of a heat resistant plastic, for example, while O-ring 58 may be made of a heat resistant rubber. FIG. 5 also depicts a gap 60 that is located between and defined by fuel injector alignment tab 34 and body 62 of fuel injector 26 . Gap 60 exists for insertion of a sidewall of fuel injector cup 36 , as will be explained later.
FIGS. 6 and 7 depict views of fuel injector cup 36 which is a cover having an open end 64 and a rounded end 66 that is open to a lesser degree. Rounded end 66 has a hole through which fuel is received from fuel rail 24 before such fuel passes into fuel injector 26 . Fuel injector cup 36 may have a flange 68 that may protrude at ninety degrees from a longitudinal axis 70 of fuel injector cup 36 . Longitudinal axis 70 may be common to fuel injector 26 and fuel injector cup 36 . Fuel injector cup 36 may be hollow to accommodate fuel injector inlet 56 and O-ring 58 , which may be located around injector inlet 56 . As depicted in FIG. 7 , flange 68 may define a notch 74 for part of a depth of flange 68 or an entire depth of flange 68 to permit unobstructed access directly to sidewall 72 of fuel injector cup 36 .
Turning now to FIG. 8 , enlarged cross-sectional view of fuel injector alignment tab 34 depicts an alignment tab column 76 protruding from body 62 of fuel injector 26 . In cross section, alignment tab column 76 widens to a tab head 78 that defines a first alignment tab prong 80 and a second alignment tab prong 82 . Between first alignment tab prong 80 and second alignment tab prong 82 , a prong gap 84 is defined. Alignment tab prongs 80 , 82 are mirror images of each other and each exhibits a retention feature that operates in conjunction with flange 68 of fuel injector cup 36 . Alignment tab prongs 80 , 82 may each be dual angle prongs and each may have dual contact surfaces that may contact flange 68 , such as for insertion and removal of fuel injector alignment tab 34 . More specifically, first alignment tab prong 80 may have a contact surface 86 and second alignment tab prong 82 may have contact surface 88 , which is a mirror image of contact surface 86 . Contact surfaces 86 , 88 may be considered removal surfaces since contact surfaces 86 , 88 contact flange 68 upon removal of fuel injector alignment tab 34 through notch 74 of flange 68 . Continuing, a removal angle “B” may be formed between surface 86 (i.e surface 86 extended into tab) and sidewall 94 of tab head 78 . The same angle as angle “B” may be formed between surface 88 (i.e surface 88 extended into tab) and sidewall surface 96 of tab head 78 .
First alignment tab prong 80 may have a contact surface 90 and second alignment tab prong 82 may have contact surface 92 , which is a mirror image of contact surface 90 . Contact surfaces 90 , 92 may be considered insertion surfaces since contact surfaces 90 , 92 contact flange 68 upon insertion of fuel injector alignment tab 34 into or through notch 74 of flange 68 . Continuing, an insertion angle or entry angle “A” may be formed between surface 90 and interior surface 98 that faces gap 84 of tab head 78 . The same angle as angle “A” may be formed between surface 92 and interior surface 100 that faces gap 84 of tab head 78 . Angle “A” which is an entry angle, may be smaller than angle “B,” which is a removal angle. Angle “A” ensures ease of insertion during alignment of injector 26 with fuel rail 24 while angle “B” ensures an ease of removal of injector 26 from flange 68 of fuel injector cup 36 for servicing; however, due to angle “B” being a larger angle, removal requires more force than insertion.
Turning now to FIGS. 9-17 , additional details of fuel injector assembly 30 will be presented. FIG. 9 depicts a side view of fuel injector 26 including fuel injector cup 36 attached (e.g. brazed) to fuel rail 24 . In FIG. 9 , fuel injector cup 36 is mounted or clipped onto fuel injector alignment tab 34 , which may be plastic and overmolded directly to fuel injector 26 . A fuel injector exit tip 102 may be placed directly into an engine combustion chamber when in use. Turning now to FIGS. 10 and 11 , a first position of fuel injector 26 relative to fuel injector cup 36 will be explained. FIG. 10 depicts injector inlet 56 of injector 26 slightly beyond entrance 104 of fuel injector cup 36 . That is, injector inlet 56 is slightly within fuel injector cup 36 . When injector 26 is in the position depicted in FIG. 10 , fuel injector alignment tab 34 is at the position depicted in FIG. 11 ; thus, first and second alignment prongs 80 , 82 of fuel injector alignment tab 34 have not yet entered into notch 74 in flange 68 of fuel injector cup 36 . Similarly, O-ring 58 has not yet entered into an interior of fuel injector cup 36 .
Turning now to FIGS. 12 and 13 , FIG. 12 depicts injector inlet 56 within entrance 104 of fuel injector cup 36 such that O-ring 58 contacts interior sidewall 107 of fuel injector cup 36 . More specifically, O-ring 58 contacts interior wall 107 adjacent or beside flange 68 . When injector 26 is in the position depicted in FIG. 12 , fuel injector alignment tab 34 is at the position depicted in FIG. 13 . Thus, first and second alignment prongs 80 , 82 of fuel injector alignment tab 34 have entered into gap or notch 74 in flange 68 of fuel injector cup 36 . More specifically, upon first and second alignment prongs 80 , 82 contacting a first flange sidewall 106 and a second flange sidewall 108 during insertion in a direction indicated by arrow 110 , first and second alignment prongs 80 , 82 begin to converge or move toward each other because prongs 80 , 82 may be made from a flexible, plastic material. Additionally, because first and second alignment prongs 80 , 82 have angled surfaces that contact flange 68 , the insertion force necessary to compress prongs 80 , 82 upon contact with flange 68 is reduced over prongs with a greater contact angle which would require a greater insertion force in direction depicted by arrow 110 .
Turning now to FIGS. 14 and 15 , FIG. 14 depicts injector inlet 56 of injector 26 protruding deeper or farther within fuel injector cup 36 compared to FIG. 12 . In FIG. 14 , O-ring 58 contacts interior wall 107 of fuel injector cup 36 and is located beyond or deeper than flange 68 . When injector 26 is in the position depicted in FIG. 14 , fuel injector alignment tab 34 is at the position depicted in FIG. 15 . Thus, first and second alignment prongs 80 , 82 of fuel injector alignment tab 34 have been compressed toward each other by contact with flange 68 and forced deeper into or through notch 74 in flange 68 of fuel injector cup 36 . First alignment prong 80 has an apex 111 while second alignment prong 82 has an apex 112 . Apex 111 is the juncture of surface 86 and surface 90 of prong 80 , and apex 112 is the juncture of surface 88 and surface 92 of prong 82 . Upon insertion, when apexes 111 , 112 moving completely through notch 74 , prongs 80 , 82 become locked to a degree and will require a force to remove that is greater than the force of insertion.
As depicted in FIG. 15 , prongs 80 , 82 have moved through notch 74 to the extend that apexes 110 , 112 are on a flange top side 114 as opposed to their position in FIGS. 11 and 13 when apexes 110 , 112 are on a flange bottom side 116 . Thus, when apexes 110 , 112 are on a top side 114 of flange 68 , prongs 80 , 82 are again relaxed and not under a bending stress as none of surfaces 86 , 88 , 90 , 92 are in contact with flange 68 . When fuel injector 26 and more specifically, prongs 80 , 82 are positioned as depicted in FIG. 15 , fuel injector 26 is secured to fuel injector cup 36 and fuel rail 24 and thus injector 26 may not easily become dislodged or disconnected from fuel injector cup 36 during shipping and also fuel injector 26 may not become misaligned with fuel injector cup 36 or fuel rail 24 because fuel injector alignment tab 34 also aligns longitudinal axis of injector 26 with fuel rail 24 . Longitudinal axis 70 of fuel injector 26 may be aligned (e.g. perpendicularly) with longitudinal axis of fuel rail 24 since a width 118 of tab head 78 , which is parallel to movement direction of prongs 80 , 82 , has a close tolerance with width of notch 74 . That is, tab head 78 has a width 118 nearly equal to that of width of notch 74 . Although FIG. 15 depicts a location of fuel injector alignment tab 34 relative to flange 68 such that fuel injector alignment tab 34 will not easily pass back through alignment tab 34 , because prong gap 84 is still within notch 74 , prongs 80 , 82 may still be susceptible to compression toward each other, or movement in general if force is applied to injector 26 or fuel rail 24 .
FIGS. 16 and 17 depict yet another position of fuel injector alignment tab 34 relative to flange 68 of fuel injector cup 36 . More specifically, fuel injector alignment tab 34 may be positioned such that an entirely solid portion 119 of tab head 78 lies within notch 74 of flange 68 . That is, base 120 of FIG. 17 is a non-linear or curved portion defining prong gap 84 , is not located within notch 74 of flange 68 . After installing or inserting fuel injector alignment tab 34 through notch 74 , as depicted in FIG. 17 , no force is exerted on prongs 80 , 82 since prongs 80 , 82 are located above or outside of notch 74 . Thus, combined with an interference fit or a close tolerance fit of solid portion 119 of tab head 78 and flange sidewalls 106 , 108 , non-movement of prongs 80 , 82 may be ensured. With non-movement of prongs 80 , 82 with at least an interference fit or a close tolerance fit between solid portion 119 of tab head 78 and flange sidewalls 106 , 108 , alignment of injector tip 56 with fuel rail 24 may also be ensured. Additionally, to further reduce or prevent any side to side motion or movement of injector 26 within fuel injector cup 36 , O-ring 58 compresses against cup interior sidewall 107 in an interference fit, as depicted in FIGS. 12 , 14 and 16 .
The teachings of the present disclosure reveal numerous advantages. An advantage is that O-ring 58 will be uniformly compressed within fuel injector cup 36 because of fuel injector alignment tab 34 , which prevents inserting fuel injector 26 into fuel injector cup 36 in an angled manner. Thus, the longitudinal axis of fuel injector cup 36 and longitudinal axis of injector 26 will always coincide. Another advantage is that fuel injector alignment tab 34 is an integral part of fuel injector 26 as opposed to a separate piece. By integrating fuel injector 26 and fuel injector alignment tab 34 by overmolding, for example, separate pieces and additional fasteners are not necessary. Yet another advantage is that the force necessary to install and remove fuel injector alignment tab 34 from flange 68 of fuel injector cup 36 are different. The force required for installation is less than the force required for removal of the fuel injector alignment tab 34 .
The foregoing description of the embodiments has been provided for purposes of illustration and description. It is not intended to be exhaustive or to limit the invention. Individual elements or features of a particular embodiment are generally not limited to that particular embodiment, but, where applicable, are interchangeable and can be used in a selected embodiment, even if not specifically shown or described. The same may also be varied in many ways. Such variations are not to be regarded as a departure from the invention, and all such modifications are intended to be included within the scope of the invention. | Attaching a fuel injector to a common rail may utilize a fuel injector and an integral tab that has a solid head portion from which a first flexible prong and a second flexible prong protrude and define a gap therebetween. A fuel injector cup may define a notch through which the first prong and the second prong reside to secure the fuel injector to the fuel injector cup, which is attached to the rail. A first prong interior straight wall surface and a second prong interior straight wall surface may face the gap and be parallel. The prongs may define entry contact surfaces and exit contact surfaces that meet at prescribed angles to aid in insertion and hinder retraction of the injector tab from the injector cup. The tab defines a solid head portion below the gap that resides in the notch. | 5 |
[0001] This application claims priority on Japanese Patent Application 2008-271354 filed Oct. 21, 2008.
BACKGROUND OF THE INVENTION
[0002] This invention relates to a base for fastening and carrying thereon an underwater camera contained inside a waterproof camera housing as it is being used for flash lighting, serving to attach thereto an arm having an external flash light provided at its tip.
[0003] External flash lamps are used in underwater photography because the quantity of available light is often insufficient. Since water contains small dust particles such as grains of sand as well as planktons that float around, external lamps are often placed away from a camera with its waterproof housing that surrounds it (hereinafter referred as an “underwater camera”) by distances of from ten and some centimeters to several tens of centimeters such that these dust particles, etc. will not appear conspicuously on the obtained image. For this reason, it has been known (as disclosed, for example, in Japanese Patent Publication Tokkai 11-237688) not only to fasten an underwater camera to a base but also to provide an external flash lamp at the tip of an arm and to connect the arm and the base together. In such a case, the base is a planar member to be screwed to the bottom of the housing of the underwater camera. In certain situations, a grip may be provided between the arm and the base.
[0004] FIG. 1 is a diagonal view for showing the structure of a conventional base for a general-purpose underwater camera, and FIG. 2 is a diagonal view for showing the manner in which the base of FIG. 1 may be attached to the underwater camera. For the sake of convenience, the main body of the camera is omitted in FIGS. 1 and 2 , and the arm is not included in FIG. 2 .
[0005] In these figures, numeral 1 indicates the base, numeral 2 indicates the waterproof camera housing (hereinafter also referred to simply as the housing), and numeral 3 indicates an arm. The bottom of the housing 2 is provided with a pedestal 4 with a screw hole 6 formed therethrough for attachment with a fixing screw 5 . Leg structures 7 A and 7 B are further provided to the right-hand and left-hand sides of the bottom of the housing 2 for stabilizing the underwater camera.
[0006] The base 1 has an elongated hole 8 therethrough for passing therethrough the fixing screw 5 such that only its axial part (that is, the screw part and the cylindrical part that is continuously connected to it) can be freely moved in the direction of the width (hereinafter referred to as the “transverse direction”), depending on the type of the housing 2 that is being used. A protrusion 9 with a specified length is also provided at one end part of the base 1 in the direction of the width for the purpose of positioning the housing 2 .
[0007] When the housing 2 is affixed to the base 1 thus structured, the axial part of the fixing screw 1 is firstly passed through the elongated hole 8 of the base 1 from below. While the tip of the fixing screw 5 has been somewhat inserted into the screw hole 6 of the housing 2 , the housing 2 is moved in the direction of the width of the base 1 for its positioning by pressing the back walls of the leg structures 7 A and 7 B against the protrusion 9 of the base 1 . After the positioning is completed, the fixing screw 5 is fully inserted into the screw hole 6 . FIG. 1 shows the fully affixed condition thus achieved.
[0008] The housing 2 may be attached to the base 1 backward, as shown in FIG. 3 , or in the reversed direction as compared to the attachment explained above. In this situation, the front wall of the pedestal 4 on the housing 2 comes to contact the protrusion 9 for the positioning of the housing 2 .
[0009] The positioning as described above is necessary because the structure of the housing 2 varies according to the type of the camera that is being used and hence the distance between the screw hole 6 and the protrusion 9 of the base 1 or the front wall of the pedestal 4 also varies. In order to use as a general-purpose base, it is necessary that these distances be adjustable according to the type of the housing 2 .
[0010] The conventional general-purpose base 1 as described above had many problem points. For example, as the user holds the housing 2 in water for underwater photography, the position of the external flash lamp must be adjusted according to the target object to be photographed if flash lighting is required. The user will carry out this adjustment by varying the angle of the external flash lamp at the tip of the arm 3 affixed to the base 1 . Since the arm 3 and the external flash lamp attached to its tip are quite heavy, however, the housing 2 tends to easily undergo a rotational displacement around the leg structures 7 A and 7 B or the pedestal 4 in contact with the protrusion 9 of the base 1 , as shown in FIG. 4 . If the housing 2 thus undergoes a rotational displacement, the fixing screw 5 in contact with the bottom surface of the base 1 also rotates by the same amount, becoming loose. This makes it still easier for the housing 2 to rotate, thereby initiating a vicious cycle.
[0011] In view of this problem, it has recently been proposed to prevent the rotational displacement of the housing 2 by pasting a frictional sheet of a rubber material on the surface of the base 1 where the bottom part of the pedestal 4 of the housing 2 comes into contact such that the rotational displacement of the housing 2 can be prevented. Since the arm 3 and the external flash lamp at its tip are very heavy, however, this approach has been proved insufficient for dependably preventing the rotational displacement. Since this problem of preventing rotational displacement is distracting to the user from concentrating on the target object to be photographed, there has been a significant demand for an improvement.
[0012] Another problem associated with the conventional general-purpose base 1 has been that the loosened screw must be tightened frequently while the user is holding the equipment while being engaged in underwater photography, causing a significant stress on the user while diving.
SUMMARY OF THE INVENTION
[0013] It is therefore an object of this invention to eliminate these problems of prior art technologies by providing an improved base for an underwater camera, which can be used for different housings of different types, not causing its fixing screw to become loose during underwater photography while the user is diving, and allowing the housing to be securely affixed to the base.
[0014] In view of the object described above, this invention relates to a base for an underwater camera with a camera enclosed inside a watertight housing, serving to have the underwater camera affixed and to attach an arm with a flash lamp provided at its tip part when flash lighting is carried out and comprising a base main body having an elongated planar fixing part where the underwater camera is fastened, a mobile holder plate for fastening the underwater camera, having a protrusion for limiting displacement of the camera housing in the direction of the width of the base (defined as the transverse direction) and being disposed on the base main body so as to be movable in the transverse direction, a pair of set screws for attaching the mobile holder plate to the base main body, and a fixing screw for fastening the underwater camera, wherein the base main body has a fixing hole for allowing only an axial part of the fixing screw to pass through and a pair of elongated holes formed on both sides of the fixing hole for allowing only axial parts of the set screws to pass through and to be movable in the transverse direction, and wherein the mobile holder plate has an elongated fixing hole for allowing the axial part of the fixing screw to pass through and to be movable in the transverse direction and fixing screw holes for engaging with the pair of set screws.
[0015] Such a base may have a guide part that guides the mobile holder plate from both sides in the transverse direction.
[0016] Such a base may further comprise a pair of supplementary mobile holder plates on both sides of the mobile holder plate on the base main body, each of the pair of supplementary mobile holder plates having a protrusion on one end part in the transverse direction on a front surface, having an adjusting set screw passed through corresponding one of the elongated holes provided in the transverse direction of the base main body for adjusting its position in the transverse direction and being adapted to be fastened by sandwiching leg structure of the camera housing by inner walls of the protrusions of the pair of supplementary mobile holder plates.
[0017] In the above, each of the pair of supplementary mobile holder plates may have a backside protrusion on one end part in the transverse direction on a back surface and be adapted to be fastened as outer walls of the backside protrusions push and open the leg structures of the camera housing when the pair of supplementary mobile holder plates is inverted to be attached to the base main body.
[0018] In the above, the base main body may have supplementary guide parts formed thereon for guiding the pair of supplementary mobile holder plates from both sides in the transverse direction.
[0019] In the above, the base main body may have an arm-attaching part formed on at least one longitudinal end part thereof for attaching the arm.
[0020] In the above, the base main body may have a grip-attaching part formed on at least one longitudinal end part thereof for attaching the arm through a grip.
[0021] In the above, the base main body and the grip may be integrally formed.
[0022] The invention further relates to a base for an underwater camera with a camera enclosed inside a watertight housing, serving to have the underwater camera affixed and to attach an arm with a flash lamp provided at its tip part when flash lighting is carried out and comprising a base main body having an elongated planar fixing part where the underwater camera is fastened and a protrusion formed at one end part in the transverse direction on a front surface for preventing the camera housing from moving in the transverse direction, a pair of mobile holder plates disposed on the base main body so as to be movable in the transverse direction, each having a protrusion at one end part on a front surface in the transverse direction, a set screw for attaching each of the pair of mobile holder plates to the base main body, and a fixing screw for fastening the underwater camera, the base main body having an elongated fixing hole for allowing only an axial part of the fixing screw to pass through and to be movable in the transverse direction and a pair of elongated setting holes formed on both sides of the elongated fixing hole for allowing only axial parts of the set screws to pass through and to be movable in the transverse direction, the mobile holder plates each having an elongated fixing screw hole for engaging with the pair of set screws, and the camera housing being adapted to be fastened by sandwiching leg structures of the camera housing with inner walls of the protrusions of the mobile holder plates.
[0023] In the above, the base main body may have a guide part that guides the mobile holder plate from both sides in the transverse direction.
[0024] In the above, each of the pair of mobile holder plates may have a backside protrusion on one end part in the transverse direction on a back surface and may be adapted to be fastened as outer walls of the backside protrusions push and open the leg structures of the camera housing when the pair of mobile holder plates is inverted to be attached to the base main body.
[0025] In the above, the base main body may have an arm-attaching part formed on at least one longitudinal end part thereof for attaching the arm.
[0026] In the above, the base main body may have a grip-attaching part formed on at least one longitudinal end part thereof for attaching the arm through a grip.
[0027] In the above, the base main body and the grip may be integrally formed.
[0028] Such a base may further comprise a connecting protrusion that connects the protrusions on the pair of mobile holder plates, the connecting protrusion and the protrusions on the pair of mobile holder plates together serving to fasten the camera housing.
[0029] A base according to this invention, being characterized as above, can be used with different types of camera housings without allowing the camera-fixing screw to become loosened and without causing any rotational displacement of the housing with respect to the base while the user is engaged in underwater photography. Since the camera housing can be so securely attached to the base and the base can behave as if it had been produced especially for the individual camera housing, the user can concentrate on diving or underwater photography.
BRIEF DESCRIPTION OF THE DRAWINGS
[0030] FIG. 1 is a diagonal view for showing the structure of a conventional base for a general-purpose underwater camera.
[0031] FIG. 2 is a diagonal view for showing the manner in which the base of FIG. 1 may be attached to the underwater camera.
[0032] FIG. 3 is a diagonal view for showing the housing attached to the base of FIG. 1 in the reversed direction.
[0033] FIG. 4 is a diagonal view for showing the housing undergoing a rotational displacement.
[0034] FIG. 5 is a diagonal view for explaining the structure of a base according to a first embodiment of this invention.
[0035] FIG. 6 is a diagonal exploded view of the base of FIG. 5 as seen from below.
[0036] FIG. 7 is a diagonal exploded view of the base of FIG. 5 as seen from above.
[0037] FIG. 8 is an exploded diagonal view for explaining the structure of a base according to a second embodiment of this invention as seen from below.
[0038] FIG. 9 is a diagonal view showing a camera housing attached to the base of FIG. 8 .
[0039] FIG. 10 is a diagonal view for explaining the structure of a base according to a third embodiment of the invention as seen from below.
[0040] FIG. 11 is a diagonal view of the base of FIG. 10 as seen from above.
[0041] FIG. 12 is a diagonal view of a base for an underwater camera which is preferably usable with a large camera housing.
[0042] FIG. 13 is a diagonal view of a base for an underwater camera integrated with a grip.
[0043] FIG. 14 is a diagonal view for explaining the structure of a base for an underwater camera according to a fourth embodiment of the invention.
[0044] FIG. 15 is an exploded diagonal view of the base of FIG. 14 as seen from above.
[0045] FIG. 16 is a diagonal view of a large camera housing in a fixed condition.
[0046] FIG. 17 is a diagonal view for explaining the structure of a base for an underwater camera according to a fifth embodiment of the invention.
[0047] FIG. 18 is an exploded diagonal view of the base of FIG. 17 as seen from above.
[0048] FIG. 19 is a diagonal view of a large camera housing in a fixed condition.
DETAILED DESCRIPTION OF THE INVENTION
[0049] Embodiments of this invention will be described next in detail.
[0050] FIG. 5 is a diagonal view for explaining the structure of a base according to a first embodiment of this invention, FIG. 6 is a diagonal exploded view of the same base as seen from below, and FIG. 7 is a diagonal exploded view of the same base as seen from above. A situation in which an arm is attached to the base through a grip will be explained with reference to these figures. It is to be noted that the main body of the camera is omitted from FIG. 7 , and the grip and the arm are omitted from FIGS. 5-7 .
[0051] In FIGS. 5-7 , numeral 11 indicates the base, and numeral 12 indicates a watertight camera housing. The base 11 comprises an elongated planar main body 13 and a planar mobile holder plate 14 which is shorter than the base main body 13 in the longitudinal direction.
[0052] The bottom part of the housing 12 is provided with a pedestal 15 for fastening to the base 11 , and a camera-fixing screw hole 17 is formed near the center of this pedestal 15 for accepting a fixing screw 16 . This screw hole 17 may be of a type for fastening a tripod screw.
[0053] The base main body 13 is formed with a circular camera-fixing hole 18 for allowing only the axial part of the fixing screw 16 to pass through and also a pair of elongated holes 20 A and 20 B for set screws on both sides of this circular fixing hole 18 in the longitudinal direction, elongated in the direction of the width of the base main body 13 (hereinafter also referred to as the “transverse direction”), for allowing only the axial parts of a pair of set screws 19 A and 19 B such that they can be moved in the direction of the width of the base main body 13 . Screw holes 21 A and 21 B for attaching a grip are also provided on both ends of the base main body 13 .
[0054] The mobile holder plate 14 is provided nearly at its center with an elongated hole 22 , elongated in the direction of the width, for allowing the axial part of the fixing screw 16 to pass through so as to be able to move in the direction of the width and a pair of circular holes 23 A and 23 B on both sides of this elongated hole 22 in the longitudinal direction for screwing in the pair of set screws 19 A and 19 B. The circular hole 18 and the pair of elongated holes 20 A and 20 B formed in the base main body 13 are located so as to match the elongated hole 22 and the pair of circular holes 23 A and 23 B formed in the mobile holder plate 14 . A protrusion 24 is formed at one end part on the surface of the mobile holder plate 14 in the direction of its width so as to extend in the longitudinal direction for contacting the front wall of the pedestal 15 of the housing 12 for the purpose of positioning.
[0055] The base 11 as described above may be fastened to the housing 12 , for example, as follows. Firstly, the axial part of the set screw 19 A is passed through the elongated hole 20 A from the lower side of the base main body 13 so as to enter the hole 23 A below the mobile holder plate 14 for temporary holding. Similarly, the axial part of the other set screw 19 B is passed through the elongated hole 20 B from the lower side of the base main body 13 so as to enter the other hole 23 B below the mobile holder plate 14 for temporary holding. By these operations for temporary holding, the mobile holder plate 14 come to be fixed on the base main body so as to be movable in the direction of the width. Under this condition, the head parts of the pair of set screws 19 A and 19 B are in contact with the back surface of the base main body 13 , while the axial parts of these set screws 19 A and 19 B are prevented from moving in the longitudinal direction although they can freely move in the direction of the width.
[0056] Next, the housing 12 is placed above the mobile holder plate 14 , and the mobile holder plate 14 is moved slidingly in the direction of the width such that the front wall of the pedestal 15 comes to contact the protrusion 25 . Then, the axial part of the fixing screw 16 is passed sequentially through the circular camera-fixing hole 18 of the base main body 13 and the elongated hole 22 of the mobile holder plate 14 . Next, not only the camera-fixing screw 16 but also the pair of set screws 19 A and 19 B is tightened completely under the condition that the axial positions of the fixing screw 16 and the screw hole 17 of the pedestal 15 of the housing 12 are matched. As a result, the movement of the housing 12 in the direction of the width is limited by the protrusion 24 of the mobile holder plate 14 and the fixing screw 16 while its longitudinal movement is limited since the pair of set screws 19 A and 19 B is inserted into the elongated holes 20 A and 20 B. In other words, no rotational displacement is allowed to occur.
[0057] Although the first embodiment of the invention was explained above by way of an example with a housing having a pedestal and using a grip while not having any leg structure, it goes without saying that this is not intended to limit the scope of the invention. The invention is intended to include situations where leg structures are provided and an arm is directly to be attached.
[0058] Next, a second embodiment of the invention is described. FIG. 8 is an exploded diagonal view for explaining the structure of a base for an underwater camera according to the second embodiment of the invention as seen from below, and FIG. 9 is a diagonal view showing a housing attached to this base. In these two figures, the components which are similar to or like those already explained with reference to the first embodiment of the invention are indicated by the same numerals and will not be repetitively explained. For simplifying the disclosure, the camera main body is not illustrated in FIGS. 8 and 9 .
[0059] The base 11 according to this embodiment of the invention, like the base according to the first embodiment, comprises an elongated planar base main body 13 and a planar mobile holder plate 14 which is shorter than the base main body 13 in the longitudinal direction.
[0060] The base main body 13 according to this embodiment has a guide groove 25 formed with a shape which is complementary to the shape of the mobile holder plate 14 such that the mobile holder plate 14 can move in the direction of the width by being guided along the both wall surfaces of this guide groove 25 . In other respects, the structure of this embodiment is the same as that of the first embodiment. FIG. 9 shows a situation where a grip 26 is in an attached condition.
[0061] Being thus structured, the second embodiment is advantageous, in addition to having the advantages of the first embodiment, in that the displacement of the mobile holder plate 14 in the longitudinal direction can be limited without strictly matching the measurements of the set screws 19 A and 19 B and the elongated holes 20 A and 20 B because the mobile holder plate 14 is guided by the walls of the guide groove 25 . This embodiment is advantageous also because of the ease of attachment.
[0062] Next, a third embodiment of the invention is described. FIG. 10 is a diagonal view for explaining the structure of a base for an underwater camera according to the third embodiment of the invention as seen from below, showing the situation before the housing 12 is attached to the base 11 , and FIG. 11 is a diagonal view of the same base as seen from above after the housing 12 has been attached to the base 11 . In these two figures, the components which are similar to or like those already explained with reference to the first embodiment of the invention are indicated by the same numerals and will not be repetitively explained. For simplifying the disclosure, the camera main body is not illustrated in FIGS. 10 and 11 .
[0063] The base 11 according to this embodiment of the invention is preferably used when the housing 12 is structured with leg structures 27 A and 27 B in addition to a pedestal 15 on its bottom, comprising not only an elongated planar main body 13 and a planar mobile holder plate 14 which is shorter than the base main body 13 in the longitudinal direction but also a pair of supplementary mobile holder plates 28 A and 28 B. For this reason, the base main body 13 has additional elongated holes 30 A and 30 B for set screws formed on each side of the elongated holes 20 A and 20 B, elongated in the direction of the width such that the axial parts of set screws 29 A and 29 B can be passed therethrough while allowing them to move in the direction of the width. Moreover, the base main body 13 has not only a guide groove 25 formed with a shape which is complementary to the shape of the mobile holder plate 14 but also additional guide grooves 31 A and 31 B on each of its sides in the shape which is complementary to the shape of the supplementary mobile holder plates 28 A and 28 B. The supplementary mobile holder plates 28 A and 28 B are movable in the direction of the width, being guided respectively by the wall surfaces of these guide grooves 31 A and 31 B. Protrusions 32 A and 32 B are formed at one end on the front surface respectively of the supplementary mobile holder plates 28 A and 28 B, and circular screw holes (not shown) are formed on the back surfaces for the set screws 29 A and 29 B. The length of the supplementary mobile holder plates 28 A and 28 B in the longitudinal direction is shorter than that of the mobile holder plate 14 . The supplementary mobile holder plates 28 A and 28 B are disposed such that the protrusions 32 A and 32 B are on the side opposite to the protrusion 24 of the mobile holder plate 14 . The housing 12 is fastened such that the leg structures 27 A and 27 B are sandwiched by the front walls of the protrusions 32 A and 32 B of the supplementary mobile holder plates 28 A and 28 B.
[0064] A base thus structured will have not only the advantages described above but also the advantage of being capable of making the fastening even securer, and this additional advantage will be particularly demonstrated when the housing 12 is large.
[0065] FIG. 12 shows a base 11 which is preferable for using with a large housing. This example is characterized wherein the pair of supplementary mobile holder plates 28 A and 28 B is provided with protrusions 33 A and 33 B at places somewhat removed inwardly from one end part of the back surface in the direction of the width such that it can be fastened by turning the pair of supplementary mobile holder plates 28 A and 28 B around to attach them to the base main body 13 and by opening the leg structures 27 A and 27 B of the housing 12 wider with the outer walls of the protrusions 33 A and 33 B on the back surfaces of the pair of supplementary mobile holder plates 28 A and 28 B.
[0066] The screw holes to be provided to the pair of supplementary mobile holder plates 28 A and 28 B are preferably throughholes such that any of the protrusions 32 A, 32 B, 33 A and 33 B can be used.
[0067] FIG. 13 is a diagonal view of a base 11 for an underwater camera integrated with a grip 34 . Such a base may be conveniently selected by the user according to the type and size of the flash lamp to be used and the purpose of the use.
[0068] Next, a fourth embodiment of the invention is described. FIG. 14 is a diagonal view for explaining the structure of a base for an underwater camera according to the fourth embodiment of the invention, and FIG. 15 is an exploded diagonal view of this base as seen from above. A situation where an arm is attached to the base through a grip will be explained as an example. For the convenience of explanation, the camera main body is not illustrated in FIG. 15 and the grip and the arm are not illustrated in FIGS. 14 and 15 .
[0069] In these figures, numeral 11 indicates the base, and numeral 12 indicates a watertight camera housing. The base 11 comprises an elongated planar main body 13 and a pair of planar mobile holder plates 41 A and 41 B which are shorter than the base main body 13 in the longitudinal direction.
[0070] The bottom part of the housing 12 is provided with a pedestal 15 for fastening to the base 11 and a pair of leg structures 27 A and 27 B. A screw hole 17 is formed near the center of this pedestal 15 for accepting a fixing screw 16 . This screw hole 17 may be of a type for fastening a tripod screw.
[0071] The base main body 13 is formed with an elongated hole 42 for allowing only the axial part of the fixing screw 16 to pass through such that it can be moved in the direction of the width of the base main body 13 . Guide grooves 43 A and 43 B are formed on both sides of the base main body 13 with a shape which is complementary to the shape of a pair of mobile holder plates 41 A and 41 B. These guide grooves 43 A and 43 B are provided with elongated holes 30 A and 30 B, elongated in the direction of the width of the base main body 13 , so as to pass set screws 19 A and 19 B therethrough while allowing them to move in the direction of the width of the base main body 13 . Screw holes 21 A and 21 B for attaching a grip are also provided on both ends of the base main body 13 .
[0072] The mobile holder plates 41 A and 41 B are provided with circular fixing holes 44 A and 44 B, respectively for having the set screws 19 A and 19 B screwed in. Protrusions 45 A and 45 B are formed, extending in the longitudinal direction, at one end part in the direction of the width on the surface of the mobile holder plates 41 A and 41 B so as to contact the front wall of the pedestal 15 of the housing 12 for the purpose of positioning. The housing 12 is fastened by sandwiching the leg structures 27 A and 27 B with the front walls of the protrusions 45 A and 45 B of the mobile holder plates 41 A and 41 B. Moreover, the mobile holder plates 41 A and 41 B are provided with protrusions 46 A and 46 B at places somewhat removed inwardly from one end part of the back surface in the direction of the width for contacting, extending in the longitudinal direction so as to contact the front walls of the leg structures 27 A and 27 B for positioning. When these protrusions 46 A and 46 B are used for positioning, the mobile holder plates 41 A and 41 B are turned over upside down, the housing 12 being fastened with the back walls of the protrusions 46 A and 46 B of the mobile holder plates 41 A and 41 B pushing and opening the leg structures 27 A and 27 B wider.
[0073] The fixing holes 44 A and 44 B provided to the pair of mobile holder plates 41 A and 41 B are preferably throughholes such that any of the protrusions 45 A, 45 B, 46 A and 46 B can be used. FIG. 16 shows a large housing 12 in a fastened condition.
[0074] Next, a fifth embodiment of the invention is described. FIG. 17 is a diagonal view for explaining the structure of a base for an underwater camera according to the fifth embodiment of the invention, and FIG. 18 is an exploded diagonal view of this base as seen from above. A situation where an arm is attached to the base through a grip will be explained as an example. For the convenience of explanation, the camera main body is not illustrated in FIG. 18 and the grip and the arm are not illustrated in FIGS. 17 and 18 .
[0075] In FIG. 11 , numeral 11 indicates the base, and numeral 12 indicates a watertight camera housing. The base 11 comprises an elongated planar main body 13 and a planar mobile holder plate 14 which is shorter than the base main body 13 in the longitudinal direction.
[0076] The base 11 according to this embodiment of the invention is of a structure having a pair of planar mobile holder plates 41 A and 41 B (as in the fourth embodiment of the invention) connected by a connector 47 . Protrusions 48 and 49 are shown as being formed respectively on the front surface and the back surface of this connector 47 but there may be only one of these protrusions present. The base 11 according to the fifth embodiment of the invention is the same as that according to the fourth embodiment of the invention in other respects.
[0077] The base 11 according to the fifth embodiment of the invention is fastened as the protrusion 48 is pressed against the pedestal 15 but the position of the housing 12 may be reversed in the forward-backward direction such that it may be fastened as described above.
[0078] With the base 11 thus structured, too, the housing 12 can be fastened to the base 11 securely without causing any rotational displacement.
[0079] FIG. 19 shows a large camera housing in a fixed condition.
[0080] Although the present invention has been described above by way of several embodiments, it goes without saying that they are not intended to limit the scope of the invention and that many modifications and variations are intended to be included within the scope of this invention. | A base, securely attachable to any type of watertight housing for an underwater camera without causing rotational displacement during its use for underwater photography, includes an elongated main body and a holder plate disposed on the main body which is transversely movable. The base has a protrusion for preventing transverse motion of a pedestal or a leg structure on the housing. A pair of set screws is provided in addition to a fixing screw that is passed through a fixing hole through the base main body to fasten the base to the camera housing. The base main body has a fixing hole for the fixing screw and a pair of elongated holes for passing the set screws so as to be transversely movable. The holder plate has an elongated hole for passing the fixing screw so as to be transversely movable and screw holes for engaging the set screws. | 6 |
BACKGROUND OF THE INVENTION
This invention relates to a process for the production of flame resistant, self-extinguishing moulded polymer articles, in particular to a process for the production of flame resistant, self-extinguishing polyacrylonitrile filaments.
The production of polyacrylonitrile filaments which are slow to ignite and difficult to burn are gaining increasingly in importance. Flame resistant fibers produced from these filaments are required mainly for nightwear, carpets, curtains, car interiors and blankets. Acrylonitrile copolymers containing vinylidene chloride polymer units have a higher flame resistance than acrylonitrile homopolymers and copolymers which do not contain vinylidene chloride units. A further increase in the flame resistance may be obtained by the presence of antimony oxide the flame retarding action of which is due to a synergistic effect with halogen compounds.
The addition of antimony oxide does, however, lead to difficulties in the course of production of the fiber due to the large particle size of antimony oxide, which is generally from 2 to 7 μm. If, for example, a 35%, by weight, spinning solution of an acrylonitrile copolymer consisting of 59%, by weight, of acrylonitrile, 37.5%, by weight of vinylidene chloride and 3.5%, by weight, of sodium methallyl sulphonate in dimethyl formamide is dry spun from a 240 aperture die with the addition of 2%, by weight, of antimony trioxide, based on the polymer solids content, then the spinning operation is subject to numerous disturbances and the filaments break in the spinning shaft. Antimony is deposited in the spinning apparatus, in particular in the pipes, pumps and packing screens and especially in the spinning die. There has been no lack of attempts to overcome these difficulties. In British Pat. No. 1,373,774, for example, there is described the preparation of antimony oxide sols with particles having a maximum dimension of 50 nm for the preparation of flame resistant additives which do not give rise to spinning troubles and matting effects. Another process (German Offenlegungsschrift No. 2,509,846) proposes the addition of at least 0.1 part, by weight, of zinc to prevent the precipitation of metallic anitmony. In German Offenlegungsschrift No. 3,008,753 there is described the preparation of a suspension of antimony oxide, water and an organic solvent and the mixing of this suspension with the viscous spinning solution as a means for producing modacrylic fibers having high flame resistance and high gloss. Another method of preparing antimony trioxide having a small particle size of at the most 10 nm involves, according to German Offenlegungsschrift No. 2,913,276, stirring together antimony trioxide and a sulphonamide and precipitating the homogenized mass into a 50% by weight aqueous dimethyl formamide solution. Other processes for the preparation of very finely divided antimony oxide recommend combinations of antimony oxide with alkali metal or alkaline earth metal antimonates (German Offenlegungsschrift No. 2,054,304) or the heating of antimony oxide to temperatures of from 400° to 570° C. (U.S. Pat. No. 3,333,970). Water-insoluble antimony complexes of antimony trichloride, α-hydroxycarboxylic acid and monoisocyanates are recommended in German Offenlegungsschrift No. 2,422,171. German Offenlegungsschrift No. 2,422,172 suggests the use of antimony esters obtained as reaction products of antimony trichloride with carboxylic acid esters as a flame proofing additive.
Common to all of the above-mentioned processes is the attempt to convert conventional antimony oxide into an antimony oxide having a smaller particle size by some means, but no truly satisfactory solution to the problem of preventing problems in the spinning process is achieved.
SUMMARY OF THE INVENTION
It was an object of the present invention to provide a process for the production of flame resistant moulded halogen-containing polymer articles which contain antimony oxide, in particular flame resistant acrylonitrile polymer filaments containing at least 40%, by weight, of acrylonitrile polymer units and at least 15%, by weight, of vinylidene chloride units, which process would substantially avoid difficulties in the production of the moulded articles, in particular interference with the spinning operation or the formation of deposits in the apparatus used for producing the moulded articles, in particular the spinning apparatus, and which would not require numerous manipulations or physical or chemical changes of the antimony oxide.
It has now surprisingly been found that antimony oxide in the form of particles smaller than 50 nm, preferably smaller than 20 nm, may be homogeneously incorporated in solid polymer articles, in particular in halogen-containing polyacrylonitrile filaments, if, to the solution of a polymer in an organic solvent, there is added an antimony compound which forms antimony oxide in this solvent, preferably an antimony halide, in particular antimony trichloride, and moulded polymer articles are produced from the polymer solution and the antimony compound is reacted to form antimony oxide in these articles before or during the after-treatment. In particular, the antimony compound is added to spinning solutions of a halogen-containing acrylonitrile polymer and an organic solvent, the spinning solution is spun and the spun filaments are brought into contact with water before or during the after-treatment. When such filaments are wetted, hydrolysis takes place instantaneously and is accompanied by the separation of very finely divided antimony oxide uniformly distributed over the whole cross-section of the filament. No spinning disturbances occur during the spinning process. The antimony compound may be added directly to the spinning solution of acrylonitrile polymers and spinning solvent or the antimony compound may first be dissolved in a portion of the spinning solvent, for example dimethyl formamide, and then added to the bulk of the spinning solution.
The quantity added to the solution of polymer solids is from 1 to 10%, by weight, preferably from 2 to 5%, by weight, based on the polymer solids.
Suitable spinning solvents, apart from dimethyl formamide, are also dimethyl acetamide, dimethyl sulphoxide and ethylene carbonate.
The antimony compounds used may be compounds of trivalent or pentavalent antimony or mixtures thereof, giving rise to antimony trioxide or anitmony pentoxide or mixtures of these oxides.
It is preferred to use compounds of trivalent antimony capable of being hydrolyzed to antimony trioxide.
DETAILED DESCRIPTION OF THE INVENTION
According to a further embodiment of the present invention, the hydrochloric acid formed as a result of hydrolysis of the antimony compound to antimony trioxide may be neutralized immediately after the contact with water, for example at the end of the spinning shaft, by the addition of substances which are alkaline in reaction, such as ammonia, amines or alkaline liquors, and removed from the production and spinning solvent recovery process. The process described above for the production of flame resistant polyacrylonitrile filaments may be applied equally to various synthetic polymers spun from a spinning solution by a dry or wet spinning process. Flame resistant shaped products and articles, such as films foils, and the like, may also be produced by the process according to the present invention.
The process according to the present invention achieves optimum homogenization and distribution of the fire retarding agent over the whole cross-section of the spun filament. According to electromicrographs the particle diameter of antimony trioxide is below 50 nm, preferably from 10 to 20 nm. To obtain electron-microscopic preparations, the fibers were dissolved in dimethyl formamide and the 0.5% by weight solution was drawn out to thin films which are transparent in the electron microscope. Owing to the small size of the particles, only a few particles may be seen under an optical microscope.
As test method for the flamability and fire characteristics of textile sheet products, the measurement according to the limiting oxygen index (LOI) was carried out. In this method, the proportion, by volume, of oxygen to the sum of oxygen and nitrogen is determined in that mixture in which the textile only just continues to burn from above downwards after ignition. The LOI is defined as follows: ##EQU1##
Since the arrangement of the samples and the weight per unit area influence the results, only nonwoven webs weighing ca. 200 g/m 2 were tested by clamping them into a sample holder. The LOI value is a measure of the oxygen concentration required for combustion. The higher this concentration, the more difficult it is to ignite the filaments.
EXAMPLES
Example 1
720 g of antimony trichloride were dissolved in 64 kg of dimethyl formamide in a vessel for 30 minutes at room temperature with stirring. 36 kg of an acrylonitrile copolymer of 59%, by weight, of acrylonitrile, 37.5%, by weight, of vinylidene chloride and 3.5%, by weight, of sodium methally sulphonate were then added at room temperature with stirring. The mixture was then converted into a spinning solution by 2 hours heating at 70° C., filtered and dry spun from a 240 aperture die. No disturbances in the spinning operation occurred. The bundle of fibers obtained at the exit of the shaft was wetted with ammoniacal water over a dressing roller and wound up on reels. The spinning material, which had a total titer of 2,1600 dtex and an antimony trioxide content of 2.55%, by weight, based on the polymer solids content, was collected on spools and twisted into a cable having a total titer of 151,200 dtex. The cable was then washed in water at 80° C., stretched to 1:4 in boiling water, treated with antistatic dressing, dried, crimped and cut up into stable fibers 60 mm in length. The fibers, which had a final titer of 3.3 dtex, had a LOI value of 29.5 in the web and were completely self-extinguishing. The analytically determined antimony content of the fibers was 0.95% (calculated: 1.06%, by weight), the strength of the fibers was 2.4 cN/dtex and the fiber elongation was 40%.
Electromicrographs of the antimony trioxide particles formed in the fibers show that the particles measured less than 50 nm, in particular from 6 to 20 nm, with the most frequent particle size being approximately 10 nm.
The influence of the antimony trioxide content on the LOI value and hence the increase in flame resistance properties are illustrated in the following Table with reference to further examples. In all cases, an acrylonitrile copolymer having the chemical composition indicated in Example 1 was used, converted into a spinning solution as described in that Example and dry spun from a 240 aperture spinning die. The factor which was varied was the percentage content of antimony chloride in the spinning solution. The conditions under which hydrolysis and after-treatment took place correspond to those of Example 1. The LOI values were again determined in non-woven webs having an average weight of ca. 200 g/m 2 , the antimony content of the fibers was determined analytically and the particle size of the antimony trioxide formed was determined by electromicrographs. The particle size distribution described in Example 1 was found to apply to the fibers in all cases.
TABLE______________________________________SbCl.sub.3 content Sb.sub.2 O.sub.3 content Sb content[%, by weight, [%, by weight, [%, by weight,based on PAN based on PAN based on PAN] LOIin spinning in spinning calcu- ob- valueNo. solution] material] lated served (% O.sub.2)______________________________________1 none none 0 0.002 262 0.5 0.64 0.26 0.23 26.53 1.0 1.28 0.53 0.48 274 3.0 3.83 1.59 1.54 34.45 5.0 6.40 2.64 2.57 36.8______________________________________ PAN = Polyacrylonitrile
Example 2 (Comparison)
720 g of antimony trioxide were suspended in 64 kg of dimethyl formamide and stirred for 30 minutes at room temperature. 36 kg of an acrylonitrile copolymer having the chemical composition indicated in Example 1 were then added with stirring and converted into a spinning solution by 2 hours heating to 70° C., filtered, and then dry spun to form filaments having a total titer of 2160 dtex as described in Example 1. After an initially smooth operation, the apertures of the die began to be occluded after ca. 10 minutes and the filaments broke in the spinning shaft. In spite of numerous manipulations, the filament bundle could not be deposited and collected on spools underneath the spinning shaft due to constant disturbances of the spinning process. The experiment had to be discontinued. According to photographs obtained from an optical microscope, the conventional commercially available antimony trioxide used had an average particle size of from 2 to 7 μm. According to electromicrographs, the particle size was from 0.6 to 7 μm. The most frequent particle diameter was 4.5 μm. | Flame resistant moulded halogen-containing polymer articles which contain antimony oxide are advantageously obtained by adding a soluble antimony compound which gives rise to an antimony oxide to the solution of halogen-containing polymer in an organic solvent, producing the moulded polymer article from the polymer solution and converting the antimony compound to antimony oxide in this article before or during the after-treatment. | 3 |
FIELD OF THE INVENTION
The present invention relates to a means for mechanically desizing fabric and garments sore particularly, there is provided at least one slotted or apertured metallic abrasive panel for a rotary washer-extractor which desizes and softens fabrics and garments.
BACKGROUND OF THE INVENTION
Garment and fabric processing today includes dyeing and desizing. Sizing is important in the fabric weaving process. The size is usually removed in a finishing operation after the fabric is woven. In some fabrics e.g. denim, the size is left in to give desirable properties to the denim garment so as to improve the wear properties of the fabrics or garments. However, if the garments or fabrics are further processed, for example, treated with a crosslinking agent and/or decolorized or finished in garment form, it is necessary to first remove the sizing.
The removal of sizing is today performed in most textile plants by one or more of the following methods. The primary method of desizing is enzymatically, for example utilizing amylolytic enzymes. In garment finishing, this process is more costly. Mechanical action is another method of desizing. In this method, abrasive drum linings in extractors and/or pumice stones are utilized to improve the garment softness, give the garment special features, etc. Alkaline and acidic hydrolysis have also been employed but such techniques also cause chemical attack of the fabric so as to result in a loss of the abrasive strength of the fabric. Oxidative desizing is generally employed using large amounts of sodium hypochlorite in solution. The use of hypochlorite creates environmental problem and further can significantly degrade the fabric. Desizing is required where the fabrics or garments are to undergo further processing such as dyeing, printing, decolorization, treatment with a crosslinker, bleaching treatments and the like.
Stone washing is a technique used in the denim industry to decolorize and soften denims, especially denim garments. In practice, abrasive stones are placed with the garments or fabrics in a washer-extractor which is rotated. The stones pound the fabrics or garments and causes softening of the garment or fabric The stones further break off sizing and remove some of the dye. The stones have the disadvantage in that they are difficult to remove and also must be continuously replaced.
SUMMARY OF THE INVENTION
The present invention provides an abrasive metal panel for use in a rotary drum type washer-extractor to desize and soften fabrics and garments. The abrasive panel is provided with raised aperture or slots that protrude about 0.2 to 1 cm, preferably about 0.3 to 6 cm. The opening in the apertures or slots can be about 0.3 to 1 cm in width preferably about 0.3 to 0.5 cm. The openings should be such that button or snaps which are found on the garments do not get caught and cause damage to the garment.
The shape of the apertures is not critical. Advantageously, the apertures are round or elliptical in shape for ease in manufacture by a punching operation.
The panels can take the form of ribs within the washer-extractor or can comprise the entire interior of the washer-extractor depending on a particular use.
The washer-extractor with the abrasive panels of the invention is particularly adapted for use with an ozone treatment process for decolorizing denims.
It is therefore an object of the invention to provide a novel mechanical means for desizing and abrading fabric and garments in a single operation.
It is a further object of the invention to provide a means for desizing and abrading denims for further treatment with ozone.
It is another object of the invention to provide a method for simultaneously desizing and abrading garments and fabrics.
Other objects and advantages of the instant invention, as well as the invention itself, will become more apparent by reference to the disclosure and claims that follow, as well as the appended drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a front elevational view of a washer-extractor with one form of abrasive panels of the invention;
FIG. 2 is a perspective view of the panels of FIG. 1;
FIG. 3 is a perspective view of another form of a panel of the invention;
FIG. 4 is a cross-sectional view of the panel of FIG. 3, and
FIG. 5 is a perspective view of another form of panel of the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Although specific terms are used in the following description for the sake of clarity, these terms are intended to refer only to the particular structure of the invention selected for illustration in the drawings, and are not intended to define or limit the scope of the invention.
As seen in FIG. 1 a rotary type washer-extractor 10 having a housing 11, water lines 14,14,' controls 15 and a door 12 is provided with tumbling ribs 13 along its interior. The tumbling ribs 13 perform the operation of tumbling the fabric or garments within the washer-extractor 10 and also simultaneously desizing and abrading the fabric or garments on contact during the tumbling operation. The desizing and abrading of the fabrics or garments can take place when the garments or fabrics are wet or are immersed in an aqueous medium
Optionally, the washer-extractor can be connected through a line 17 to a source of ozone 16 so as to treat the fabrics or garments with ozone during the mechanical desizing and abrading or afterwards. It is known that ozone alone can desize the fabrics or garments. However, the mechanical desizing expedites the desizing process and further abraded the fabric or garments.
As seen in FIG. 2, the tumbling ribs 13 are formed from panels having a multiplicity of raised apertures 14. The rib 13 can be initially constructed in the rotary panel of the washer-extractor or tumbling ribs of existing washer-extractors can be modified by attaching panels with raised apertures to the existing tumbling ribs with suitable fasteners or welding. Alternatively, the panels can form the entire interior of the washer-extractor so as to provide a greater surface area to contact the raised apertures or slots and mechanically desize the fabric or garments.
FIG. 3 illustrates an abrasive panel 20 having a plurality of raised apertures 21. The panel 20 is rectangular in shape and extends across the rotating interior of the washer-extractor. The panel 20 is provided with a series of apertures which are along the entire length of the panel 20.
FIG. 4 is a cross-sectional view of the apertures found on the metal panels of the invention. The height of the wall members 15,16 of the aperature is about 0.2 to 1 cm, preferably about 0.3 to 0.6 cm. The width of the opening is about 0.3 to 1 cm, preferably about 0.3 to 0.5 cm. The raised apertures desize and abrade by impact and rubbing as on a grate. The configuration of the apertures is not essential. However, the degree of the opening should be such as to prevent snaps, buttons or the like from being caught which may cause damage to the garment or fabric. The length of the panel is not essential. Its length is preferably the length of the rotary barrel. The amount of protrusion of the panel 20 into the washer-extractor is also not critical but should be sufficient to provide a striking surface and to cause the fabrics or garments to tumble during rotation for example, about 3 to 8 cm. The panels can be in one or more sections however, a single panel across the length of the rotating barrel is preferable.
FIG. 5, illustrates a panel 30 with slots 31 substantially along its length. However, the slots can be diagonal and still provide a desizing and abrading function.
The panels may be constructed of any metal which is inert to the environment and especially to ozone, for example, stainless steel.
The panels of the invention provide an advantage over stones for producing garments having a stone washed effect since the panels have a longer wear life and the additional step of removing the stones from the apparatus and the garments is not required. Optionally, the panels may be provided with a roughened or embossed surface to increase the degree of abrasion.
The invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. The present embodiments are therefore to be considered illustrative and not restrictive, the scope being indicated by the appended claims rather than by the foregoing description, and all changes that come within the range of equivalency of the claims are therefore intended to be embraced therein. | A rotary barrel-type washer-extractor is provided with at least one slotted or apertured metal panel. The panel contains raised apertures or slots that protrude about 0.2 to 1 cm and have an opening about 0.3 to 1 cm in width. A method is also provided for desizing and abrading fabrics and garments utilizing at least one of the metal panels. | 3 |
TECHNICAL FIELD
The invention is related to the field of heat exchangers and, in particular, to a heat exchanger design in which it is easy to vary the pitch (or spacing) of the transverse tubes.
BACKGROUND ART
Heat exchangers of the type having a pair of spatially separated headers or manifolds interconnected by a plurality of transverse fluid transfer tubes are well known in the art. Corrugated fins are conventionally inserted between adjacent transverse tubes to facilitate the energy transfer between the fluid flowing through the tubes and an external atmosphere such as air. Heat exchangers, such as taught by Nakajima et al. in U.S. Pat. No. 5,052,478; Granetzke in U.S. Pat. No. 4,960,169; Wallis in U.S. Pat. No. 5,193,613; and Neshina et al. in U.S. Pat. No. 4,825,941 embody unitary headers. These headers are complex and require costly tooling to fabricate and in most instances changes are difficult and relatively expensive to make. In particular, if a change in the pitch (spacing) between the transverse tubes is desired, a whole new set of tooling is generally required. These heat exchanger configurations are not susceptible to making changes without incurring expensive tooling costs. Against this background there arises a need for a heat exchanger design in which the pitch and the number of tubes can readily be changed to accommodate prototype and/or low volume production.
SUMMARY OF THE INVENTION
A heat exchanger is disclosed having a pair of spatially separated manifolds interconnected by a plurality of transverse tubes. A plurality of manifold inserts are slidably received in the manifolds and provide a plurality of tube apertures in which the transverse tubes are received and sealed. The length of the manifold inserts is selected to provide the desired pitch or spacing between adjacent tubes.
One object of the invention is that the pitch can readily be changed to accomplish the desired heat transfer characteristics.
Another object of the invention is that it is well adapted to prototype or small volume production without costly tooling.
Still another object of the invention is that it is easy to assemble.
Yet another object of the invention is that it is easy to change the number of tubes and the size of the heat exchanger.
Still another object of the invention is that the disclosed heat exchanger may be used for cooling (radiator), oil coolers, charge air coolers, evaporators, condensers, and any other type of heat exchanger known in the art.
These and other objects of the invention will become more apparent from a reading of the specification in conjunction with the drawings.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a heat exchanger according to the invention;
FIG. 2 is a perspective view of a first embodiment of a manifold insert;
FIG. 3 is a perspective view of a second embodiment of the insert;
FIGS. 3a-3c are cross-sectional views showing alternate configurations of the "C" shaped embodiment of the manifold insert shown in FIG. 3;
FIG. 4 is a partially exploded view of a heat exchanger using "C" shaped manifold inserts;
FIG. 5 is a partially exploded view of a heat exchanger using a third embodiment of the manifold inserts;
FIG. 6 is a cross-sectional end view of the heat exchanger shown in FIG. 5;
FIG. 7 is a partial cross-sectional side view of the heat exchanger shown in FIG. 5;
FIG. 8 is a partial exploded view of a heat exchanger using a fourth embodiment of the manifold insert;
FIG. 9 is a perspective of a fifth embodiment of the manifold insert;
FIG. 10 is a partial exploded view of a heat exchanger incorporating the manifold insert shown in FIG. 9;
FIG. 11 is a perspective of a manifold insert for multiple rows of tubes; and
FIG. 12 is a perspective of a manifold insert for staggered rows of tubes.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
FIG. 1 shows a partially completed assembly of an adjustable pitch heat exchanger 10 of the type disclosed by this invention. The heat exchanger 10 has a pair of spatially separated manifolds or headers 12 and 14 interconnected by a plurality of fluid transverse tubes 16. The fluid transfer tubes are attached to the manifolds 12 and 14 by manifold inserts 20 as shall be described hereinafter. Corrugated fins 18 are inserted between and fused to the fluid transverse tubes 16 to enhance the heat exchange between a fluid flowing in the tubes 16 and an external atmosphere such as air. Once assembled, the manifolds 12 and 14, the tubes 16, fins 18 and inserts 20 are fused to each other to form an integral fluid-tight assembly. A heat exchanger 10 embodying the assembly shown in FIG. 1 may be used as a radiator, oil cooler, charge air cooler, condenser, evaporator, or any other type of heat exchange application.
A first embodiment of the manifold insert 20 is shown in FIG. 2. In this first embodiment, each manifold insert 20 is a cylindrical element 22 having contoured recesses 24 and 26 provided at opposite end faces thereof. These recesses 24 and 26 are contoured to mate with the external contour of the tubes 16. In the example shown in FIG. 1, the tubes 16 have an oblong cross-section, however, the tubes may have a circular cross-section or any other shape known in the art. The recesses 24 and 26 may be machined, stamped, coined, or made by any other method known in the art. The length or height of each insert element 22 is selectable to adjust the pitch or spacing between the adjacent tubes 16 as desired.
The manifolds 12 and 14 are made from an elongated hollow member such as cylindrical tubes 28 having longitudinal slots 30 provided along the length thereof as shown in FIG. 1. Alternatively, the elongated hollow member 28 may have a square, hexagonal or oval cross-section. The inserts 20 are slidably received in the tubes 28. The width of the longitudinal slots 30 is selected to be greater than the width of the tubes 16.
The tubes 16, manifolds 12 and 14, manifold inserts 20 and fins 18 are preferably made from an aluminum alloy clad with a solder or brazing material commercially available as "ALCAN" or "ALUMAX". The thickness of the cladding material is approximately 5 to 10% of the total thickness of the material being used and has a melting temperature significantly less than aluminum alloy.
In assembly, the manifold inserts 20 are received into each manifold 12 and 14 in an alternating arrangement with the tubes 16 until the desired number of tubes are inserted. The recesses 24 are omitted on the external faces of the end inserts 20 to provide a flat sealing surface. End caps 32 may be attached to the opposite ends of each manifold as shown in FIG. 4 to complete the assembly of the heat exchanger 10. Inlet and outlet connectors (not shown) may be added to the manifolds 12 and 14 as is known in the art.
The primary advantages of the heat exchanger as described above is that it permits a rapid and inexpensive fabrication of low production or prototype heat exchanger cores 10. It permits the use of a different number of tubes and different spacings or pitch between the tubes without the need to use expensive dies and complex labor-intensive assembly.
An alternate embodiment 120 of the manifold insert 20 is shown in FIG. 3. In this embodiment, the insert 120 is a "C" shaped element 122 having a selectable length. The recesses 24 and 26 are provided on the opposite faces of the "C" shaped element 122 opposite the open portion of the "C" as shown. The external diameter of the insert 120 is selected to be an interference fit into the manifolds 12 and 14. The "C" shaped configuration of the insert 120 permits it to be elastically compressed, eliminating a binding condition as it is inserted into the manifolds 12 and 14. The angular or arcuate width of the opening portion of the "C" shaped element may be any angle less than 160°, as shown in FIG. 3c, so that it will be self-centering within the manifold. Further, the location of the recesses 24 and 26 may vary from adjacent to the slot 30 in the manifolds 12 and 14 as shown in FIG. 3a to a location displaced inwardly as shown in FIG. 3c. FIG. 3b shows the open portion of the "C" shaped segment and the location of the recess 24 relative to the slot 30, being intermediate the positions shown in FIGS. 3a and 3c.
FIG. 4 shows the assembly procedure of a heat exchanger 10 according to the invention using inserts 120. Again, the inserts 120 and the tubes 16 are received in the manifolds 12 and 14 in an alternating sequence. The assembly is completed by inserting corrugated fins 18 between adjacent tubes 16 and the placing of end caps 32 at the opposite ends of the manifolds 12 and 14.
A still alternate embodiment 220 of the inserts 20 is shown in FIGS. 5, 6 and 7. In this embodiment, each insert 220 consists of a rectangular "U" shaped plate 222 having a punched or coined aperture 224 sized to receive the ends of the tubes 16 with an interference fit. The manifolds 12 and 14 consist of a "U" shaped member 226 having inwardly-facing rectangular channels 228 provided at the terminal ends at the ends of the legs 230 of the "U" shaped member 226. The inserts 220 are slidably received in the rectangular channels 228 as shown. In assembly, the inserts are slidably received into the rectangular channels 228 and the tubes 16 are pressed into the apertures 224. After assembly, the assembled heat exchanger is heated to fuse or braze the entire assembly as an integral fluid tight assembly.
A still alternate embodiment 320 of the insert 20 compatible with the "U" shaped manifold 226 is shown on FIG. 8. In this embodiment, the inserts 320 have the ends closed to form an open faced rectangular box 322 having a tube aperture provided therethrough. The assembly of the heat exchanger is fabricated in the same manner as the heat exchanger embodiment shown on FIG. 5.
Another embodiment 420 of the insert 20 is shown in FIGS. 9-10. In this embodiment, the insert consists of stepped plate having a rectangular upper portion 422 and a contiguous rectangular lower portion 424. The upper portion 422 has a centrally provided tube aperture 426 sized to receive an end of the tube 16 with an interference fit. The lower portion 224 has a tube clearance recess 428 provided therein.
In assembly, the inserts 420 are inserted into the rectangular channels 432 provided at the open end of the manifold 430. The manifold 430 is comparable to the manifold discussed relative to FIGS. 5 and 6 having rectangular channels 228 provided at the terminal ends of the legs 230 of a "U" shaped member 226. In the assembled position, the upper portions 422 of the inserts 420 overlap the lower portions 424 of an adjacent insert 420 as shown in FIG. 10. This embodiment of the insert 420 is suitably adapted for heat exchangers having substantial internal to external pressure differences because it provides increased sealing areas between adjacent inserts and the manifolds.
It is recognized that the invention is not limited to heat exchangers having a single row of tubes. As illustrated in FIG. 11, each insert, such as insert 520, may have two or more offset apertures 522 receiving at least a second row of tubes 16. These additional rows of tubes may be in line with each other as shown on FIG. 11 or may be staggered as shown in FIG. 12. In FIG. 12, the offset tube apertures 622 of the insert 620 are staggered relative to each other so that the tubes in the second or subsequent rows lie in between the tubes in the preceding row of tubes.
Having disclosed various embodiments of the invention, it is recognized that others skilled in the art may conceive additional embodiment and improvements within the scope of the invention as set forth in the appended claims. | A heat exchanger (10) having a pair of spatially separated manifolds (12 and 14) interconnected by a plurality of transverse tubes (16). The ends of the tubes are attached to a plurality of manifold inserts (20) slidably received in the manifolds. The lengths of the individual manifold inserts may be controlled to adjust the pitch and the number of the transverse tubes. The heat exchanger configuration is ideally suited for fabricating low production runs and prototype heat exchangers. | 5 |
BACKGROUND
[0001] This invention relates to a system and method for transferring pipe between a storage device for the pipe and a pipe string extending over a well.
[0002] Hydraulic workover units for transferring pipe between a storage device and a pipe string extending over a well, or the like, are well known. These units traditionally have been limited to a series of winches and associated equipment, requiring heavy manual labor to deliver the pipe, via the winches, from a pipe rack to an elevated position for lowering into a workbasket, or the like, for introduction into the well, and visa versa. Therefore, what is needed is a more automatic system that reduces the manual labor and the time involved in these type of operations.
BRIEF DESCRIPTION OF THE DRAWINGS
[0003] [0003]FIG. 1 is an isometric view of a system for transferring pipe according to an embodiment of the invention.
[0004] [0004]FIG. 2 is a top plan view of the system of FIG. 1.
[0005] [0005]FIG. 3 a is a diagrammatic view of a pipe feeder of the system of FIG. 1.
[0006] [0006]FIG. 3 b is an elevational view of a component of the pipe feeder of FIG. 3 a.
[0007] [0007]FIG. 4 is an isometric view of a pipe shuttle of the system of FIG. 1.
[0008] [0008]FIG. 5 a is an diagramatic view of a mechanism for raising and lowering the pipe shuttle of FIG. 4.
[0009] [0009]FIG. 5 b is an diagramatic view of an alternate embodiment of the mechanism of FIG. 5 a.
[0010] [0010]FIGS. 5 c and 5 d are diagramatic views of another alternate embodiment of the mechanism of FIG. 5 a.
[0011] [0011]FIG. 6 is a diagrammatic view of a controller used in the system of FIG. 1.
[0012] [0012]FIGS. 7 and 8 are views similar to FIGS. 1 and 2 respectively, but depicting an alternate embodiment of the system of the present invention.
[0013] [0013]FIG. 9 is a view similar to FIGS. 1 and 7, but depicting another alternate embodiment of the present invention.
DETAILED DESCRIPTION
[0014] Referring to FIGS. 1 and 2 of the drawings, the reference numeral 10 refers, in general, to a system for transferring pipe which is designed to operate in conjunction with a tower 20 . The tower 20 is designed to allow various drilling or workover operations to be performed on a well 22 which well may be an oil, a gas, or another type of well located onshore or offshore. For example, a typical operation of this type would be a snubbing operation according to which a plurality of tubulars, such as pipes, pipe joints, etc. are run into or out of the well 22 .
[0015] A deck 24 surrounds the well 22 and includes a platform 26 supported in a vertically spaced relation to the well 22 and the deck 24 by a plurality of support members 28 . The tower 20 is formed by a plurality of additional support members, or beams, extending substantially vertically from the platform 26 , along with several horizontal support members, or beams, attached to the vertical members. Since the tower 20 is conventional and does not, per se, form any part of the present invention, many details of the tower have been omitted in the interest of clarity.
[0016] The tower 20 and the platform 26 accommodate a substantially vertically extending pipe string 30 which passes through suitable openings formed in the tower 20 and the platform 26 . To this end, a mast 32 (shown partially in FIG. 1) is supported on the tower 20 and operates in a conventional manner to engage the pipe string 30 to enable it to be raised and lowered through the tower 20 and the well 22 in a conventional manner. A work basket 34 is attached to the tower 20 to permit various operations on the pipe string 30 , such as joining additional pipe joints to, and removing pipe joints from, the pipe string 30 , as will be described.
[0017] A plurality of pipe joints 40 are supported on a horizontally-extending rack 42 disposed adjacent the tower 20 , and the system 10 operates to engage a pipe joint 40 from the rack 42 and transfer it to the work basket 34 for attaching to the pipe string 30 ; and to transfer a pipe joint 40 from the pipe string 30 to the rack 42 , in a manner to be described.
[0018] A pipe feeder 44 is disposed on one side of the rack 42 for receiving the pipe joints 40 from the rack 42 . The pipe feeder 44 is shown partially in FIGS. 1 and 2 and details will be described later. The pipe feeder 44 functions to feed the pipe joints 40 between the rack 42 and a pipe lift 50 mounted for pivotal movement on the platform 26 . The pipe lift 50 is adapted to transfer the pipe joints 40 between the rack 42 and a shuttle 60 which is supported by the tower 20 , and the shuttle 60 , in turn, is adapted to transfer the pipe joints 40 between the pipe lift 50 and the work basket 34 . The pipe lift 50 and the shuttle 60 will also be described in detail later.
[0019] Details of the pipe feeder 44 are shown in FIGS. 3 a and 3 b . The pipe feeder 44 includes a motor 70 configured to drive a shaft 72 which is supported between the motor 70 at one end and a bearing 74 at the other end. Star wheels 76 and 78 are disposed on the shaft 72 in a spaced relation for rotation with the shaft 72 , and the details of the star wheel 76 are shown in FIG. 3 b . More particularly, the outer circumference of the star wheel 76 is configured to define five angular-spaced recessed portions 76 a , each of which is adapted to receive a pipe joint 40 as shown, for example, in connection with one of the recessed portions 76 a in FIG. 3 b . It is understood that the star wheel 78 is identical to the star wheel 76 , and the design is such that a pipe joint 40 will be received by corresponding recessed portions of both star wheels 76 and 78 .
[0020] Thus, the pipe feeder 44 can function to transfer a pipe joint 40 from the rack 42 to the pipe lift 50 . In this context, it is assumed that the pipe joints 40 are stacked, or otherwise arranged on the rack 42 so that they can sequentially fall from the rack 42 to the pipe feeder 44 . The motor 70 is activated to rotate the shaft 72 to allow a pipe joint 40 from the rack 42 to be received in the recessed portion 76 a of the star wheel 76 and the corresponding recessed portion of the star wheel 78 . After a pipe joint 40 is received, continual rotation of the motor 70 causes the pipe joint 40 to move angularly relative to the shaft 72 until it rolls out of the recessed portion 76 a and the corresponding recessed portion of the star wheel 78 and into pipe lift 50 . The motor 70 then pauses until the pipe lift 50 is ready to receive another pipe joint 40 and the operation can be repeated.
[0021] Also, the pipe feeder 44 can function to rotate the shaft 72 to transfer a pipe joint 40 from the pipe lift 50 to the rack 42 . In this mode, the motor 70 rotates the shaft 72 in a direction that is opposite to the direction of rotation in the previous mode to allow a pipe joint 40 from the pipe lift 50 to be received in one of the recessed portions 76 a of the star wheel 76 and the corresponding recessed portion of the star wheel 78 . After a pipe joint 40 is received, continual rotation of the motor 70 causes the pipe joint 40 to move angularly relative to the shaft 72 until it rolls out of the recessed portion 76 a of the star wheel 76 and the corresponding recessed portion of the star wheel 78 and onto the rack 42 . The motor 70 is then paused until the pipe lift 50 is ready to provide another pipe joint 40 and the operation is repeated.
[0022] As shown in FIGS. 1 and 2, one end is the pipe lift 50 is pivotally mounted to the deck 24 about a hinge 50 a , and a pair of pipe grips 52 a and 52 b are mounted in a spaced relation on the pipe lift 50 . It is understood that the pipe grips 52 a and 52 b are adapted to be actuated to move into and from a position in which they grip the pipe joint 40 , in a conventional manner. The pipe lift 50 moves between a substantially horizontal position shown by the solid lines in FIG. 1 in which a pipe joint 40 is transferred between the pipe lift 50 and the rack 42 , through an intermediate position shown by the phantom lines, and to an upright position extending at a slight angle to the vertical, also shown by the phantom lines. In the last position, the pipe lift 50 is adjacent the shuttle 60 so that a pipe joint 40 can be transferred between the pipe lift 50 and the shuttle 60 . It is understood that a conventional hydraulic cylinder, or the like, (not shown) is provided to pivot the pipe lift 50 about the hinge 50 a between the above positions.
[0023] After the pipe joint 40 from the rack 42 is grasped by the pipe grips 52 a and 52 b and the pipe lift 50 is pivoted to transfer the pipe joint 40 to the shuttle 60 , the pipe joint 40 is released to the shuttle 60 by releasing the pipe grips 52 a and 52 b . Likewise, when the pipe joint 40 from the shuttle 60 is grasped by the pipe grips 52 a and 52 b and the pipe lift 50 is pivoted to transfer the pipe joint 40 to the rack 42 , the pipe joint 40 is released to the shuttle 60 by releasing the pipe grips 52 a and 52 b.
[0024] The shuttle 60 moves vertically along a set of rails 62 a and 62 b supported by the tower 20 , with the movement being between a lower position shown in FIG. 1 in which the shuttle 60 receives a pipe joint 40 from, or transfers a pipe joint 40 to, the pipe lift 50 ; and an upper position in which it receives a pipe joint 40 from, or transfers a pipe joint 40 to, an operator in the work basket 34 .
[0025] As shown in FIG. 4, the shuttle 60 includes a base 82 and a pair of spaced grips 84 a and 84 b mounted to one surface of the base 82 in a spaced relation. A trough 86 is also mounted to the latter surface of the base 82 and extends between the grips 84 a and 84 b . Two spaced rollers 86 a and 86 b are provided on one side of the base 82 for engaging the rail 62 a , it being understood that two other rollers (not shown) are provided on the other side for engaging the rail 62 b . A bumper 88 , preferably of a relatively soft material, is disposed at one end of the base 82 for receiving an end of the pipe joint 40 .
[0026] When a pipe joint 40 is received from either the pipe lift 50 or from the work basket 34 , the pipe joint 40 is guided into position on the shuttle 60 by the trough 86 , with the bumper 88 providing a lower guide and absorbing some of the downward shock from the pipe joint 40 . It is understood that the grips 84 a and 84 b are adapted to be actuated to move into and from a position in which they grip the pipe joint 40 , in a conventional manner.
[0027] One embodiment of a mechanism for moving the shuttle 60 along the rails 62 a and 62 b between its lower position and its upper position is shown in detail in FIG. 5 a . The mechanism is referred to, in general, by the reference numeral 90 and includes a winch 94 and a cable 96 connected between the winch 94 and the shuttle 60 and extending around a pulley 100 . The winch 94 is powered in a conventional manner and rotates in one direction to take up the cable 96 and raise the shuttle 60 on the rails 62 a and 62 b using the pulley 100 , and also rotates in an opposite direction to release the cable 96 and permit the shuttle 60 to be lowered on the rails 62 a and 62 b by gravity. Although not shown in FIGS. 1 - 3 in the interest of clarity, it is understood that the mechanism 90 can be supported by the tower 20 in any conventional manner.
[0028] [0028]FIG. 5 b illustrates another embodiment of a mechanism for moving the shuttle 60 along rails 62 a and 62 b , which embodiment is referred to in general by the reference numeral 102 , and includes several components of the embodiment of FIG. 5 a which are given the same reference numerals. According to the embodiment of FIG. 5 b , the winch 94 of the embodiment of FIG. 5 a is replaced by a hydraulic cylinder 106 including a reciprocal rod 106 a having a pulley 108 mounted to its distal end. The cable 96 is connected at one end to the shuttle 60 , extends around the pulleys 100 and 108 , and is connected at its other end to a fixed structure. The hydraulic cylinder 106 can be activated to move the rod 106 a downwardly in a conventional manner to take up the cable 96 and raise the shuttle 60 on the rails 62 a and 62 b using the pulleys 100 and 108 , and to move the rod 106 a upwardly to create slack in the cable 96 so that the shuttle 60 is lowered on the rails 62 a and 62 b by gravity. Although not shown in FIGS. 1 and 2 in the interest of clarity, it is understood that the mechanism 102 can be supported by the tower 20 in any conventional manner.
[0029] [0029]FIGS. 5 c and 5 d illustrate another embodiment of a mechanism for moving the shuttle 60 along rails 62 a and 62 b , which embodiment is referred to in general by the reference numeral 110 and includes several components of the embodiment of FIG. 5 b which are given the same reference numerals. According to the embodiment of FIGS. 5 c and 5 d , the pulley 108 of the embodiment of FIG. 5 b is replaced by a set of pulleys 112 , and another set of pulleys 114 are mounted to a fixed structure in a spaced relation to the pulleys 112 . The cable 96 is connected at one end to the to the shuttle 60 , extends around the pulley 100 , and is wrapped around each pulley of the set of pulleys 112 . The cable 96 then extends to, and is wrapped around, each pulley of the set of pulleys 114 , and the other end of the cable is connected to one of the latter pulleys or to a fixed structure. The hydraulic cylinder 106 can thus be activated to move the rod 106 a downwardly to take up the cable 96 and raise the shuttle 60 on the rails 62 a and 62 b using the pulleys 100 , 112 and 114 . Also, the hydraulic cylinder 106 can be activated to move the rod 106 a upwardly to create slack in the cable 96 and thus lower the shuttle 60 on the rails 62 a and 62 b by gravity. Although not shown in FIGS. 1 and 2 in the interest of clarity, it is understood that the mechanism 110 can be supported by the tower 20 in any conventional manner.
[0030] With reference to FIG. 6, a controller 116 is provided to control the operation of the pipe feeder 44 , the pipe lift 50 , the aforementioned hydraulic cylinder 106 that controls the movement of the pipe lift 50 , the shuttle 60 , and the mechanism 90 (or 102 or 110 ). The controller 116 includes a switch 120 to select whether the system 10 raises the pipe joints 40 to, or lowers the pipe joints 40 from, the work basket 34 . After the switch 120 is set to a desired position, a control 122 may be selected to cause the system 10 to cycle through the operations described above according to which the pipe joints 40 are either transferred from the rack 42 to the work basket 34 , or vice versa. The controller 116 also includes a switch 124 to stop the shuttle 60 , a switch 125 to raise the shuttle 60 , a switch 126 to lower the shuttle 60 , and a switch 127 to cause an emergency stop of the system 10 . Since the electrical components of the controller 116 , including the above-mentioned switches, are conventional, the controller will not be described in any further detail.
[0031] In operation of the system 10 , the controller 116 is provided to a worker on the work basket 34 and, assuming that it is desired to transfer some pipe joints 40 from the rack 42 to the pipe string 30 , the switches 120 and 122 are tripped. This activates the motor 70 of the pipe feeder 44 so that it receives a pipe joint 40 from the rack 42 , and transfers it to the horizontally disposed pipe lift 50 as described above. The motor 70 then pauses until the pipe lift 50 is ready to receive another pipe joint 40 and the operation is repeated.
[0032] The pipe grips 52 a and 52 b of the pipe lift 50 are activated to grasp the pipe joint 40 , and the above-mentioned hydraulic cylinder 106 is activated to pivot the pipe lift 50 from its horizontal position shown by the solid lines in FIGS. 1 - 3 to its upright position shown by the phantom lines in FIG. 1 adjacent the tower 20 . The pipe grips 52 a and 52 b are then released and the grips 84 a and 84 b of the shuttle 60 are activated to grip the pipe joint 40 .
[0033] The mechanism 90 (FIG. 5 a ), is then activated to move the shuttle 60 vertically along the rails 62 a and 62 b until it reaches its upper position near the work basket 34 . A worker at the work basket 34 receives the pipe joint 40 and attaches a lifting device (not shown) such as a cable operated in conjunction with the mast 32 to the pipe joint 40 . The grips 84 a and 84 b of the shuttle 60 are released, and the above lifting device raises the pipe joint 40 to allow the bottom of the pipe joint 40 to be attached to the top of the pipe string 30 which is then lowered into the well 22 to allow another pipe joint 40 to be attached. During this movement of the shuttle 60 and the transfer of the pipe joint 40 to the pipe string 30 , the pipe lift 50 may be returned to its horizontal position shown in FIG. 1 to begin the next cycle. This cycle can then be repeated for a desired number of pipe joints 40 . Of course the above steps can be reversed if it is desired to transfer one or more pipe joints 40 from the pipe string 30 to the rack 42 . It is understood that either of the lifting mechanism 102 and 110 (FIGS. 5 b - 5 d ) can be used instead of the mechanism 90 in the above operations.
Alternates and Equivalents
[0034] According to the embodiment of FIGS. 7 and 8, a system 10 a is provided which is similar to the above embodiment and includes many components of the above embodiment which are given the same reference numerals. According to the system 10 a , the pipe shuttle 60 and the rails 62 a and 62 b of the previous embodiment are replaced by a shuttle 140 and a single, upright, rail 138 connected to the tower 20 in any conventional manner. The shuttle 140 is similar to the shuttle 60 with the exception that it includes a pair of arms 144 a and 144 b , respectively, that extend radially outwardly from the body of the shuttle 140 , as better shown in FIG. 8. The arms 144 a and 144 b are adapted to rotate relative to the body of the shuttle 140 in a conventional manner. A pair of grips 146 a and 146 b are attached to distal ends of the arms 144 a and 144 b , respectively, and are identical to the grips 84 a and 84 b of the shuttle 60 . It is understood that one of the lifting mechanisms 90 , 102 , or 110 of FIGS. 5 a - 5 d can be connected to the shuttle 140 to move it between a lower position and an upper position as shown in FIG. 7 and as described above.
[0035] With the shuttle 140 in its lower position, the grips 146 a and 146 b grasp the pipe joint 40 from the pipe lift 50 after the pipe lift 50 has reached its upright position described in connection with the previous embodiment. After receiving the pipe joint 40 from the pipe lift 50 , the lifting mechanism 90 , 102 , or 110 is activated to raise the shuttle 140 to its upper position. The arms 144 a and 144 b are rotated to move pipe joint 40 angularly relative to the body of the shuttle 140 and deliver the pipe joint 40 to the work basket 34 at a point relatively close to the pipe string 30 as shown in connection with the upper position of the shuttle 140 . The above operation is reversed to transfer the pipe joints 40 from the pipe string 30 to the pipe lift 50 . Otherwise the operation of the system 10 a is identical to that of the previous embodiment.
[0036] According to the embodiment of FIG. 9, a system 10 b is provided which is similar to the embodiment of FIGS. 7 and 8 and includes many component of the latter embodiment which are given the same reference numerals. According to the system 10 b , the rail 138 of the embodiment of FIGS. 7 and 8 is replaced by a rail 142 which is identical to the rail 138 with the exception that it extends through, and substantially beyond, the work basket 34 . Therefore, the shuttle 140 carrying a pipe joint 40 can be raised to a position above the work basket 34 and the arms 144 a and 144 b rotated as described above, to move the pipe joint 40 directly above the pipe string 30 for connection to the pipe string 30 by a worker. Thus, according to this embodiment, the pipe joint 40 may be raised to a position to allow it to be attached to the pipe string 30 without the use of an additional lifting device as discussed in the previous embodiment.
[0037] It is understood that other variations may be made in the foregoing without departing from the scope of the invention. For example, the tower 20 can be replaced with other types of towers or support structures. Also, the systems described above can be converted to transfer two or more pipe joints 40 in each cycle. Further, although the controller 116 was described above as being located on the work basket 34 , it can be placed in other locations, and can be adapted to communicate with the systems 10 10 a and 10 b using wired or wireless devices. Still further, in the embodiments of FIGS. 7 - 9 the pipe joint 40 may be moved laterally to a position adjacent the work basket 34 in a manner other than that described above.
[0038] Although only a few exemplary embodiments of this invention have been described in detail above, those skilled in the art will readily appreciate that many modifications are possible in the exemplary embodiments without materially departing from the novel teachings and advantages of this invention. Accordingly, all such modifications are intended to be included within the scope of this invention as defined in the following claims. | This invention relates to a system and method for transferring pipe between a storage device for the pipe and a pipe string extending over a well. | 4 |
CROSS REFERENCE TO RELATED APPLICATIONS
This application is related to U.S. Pat. No. 7,543,411, issued Jun. 9, 2009, entitled “LOW PROFILE PLASTIC PANEL ENCLOSURE” and to U.S. patent application Ser. No. 12/942,679, filed Nov. 9, 2010, entitled “COMBO WOOD AND PLASTIC MODULAR STORAGE SHED”, the entireties of which are incorporated herein by reference.
FIELD OF THE INVENTION
This invention relates generally to enclosures, such as utility or garden sheds, constructed of plastic materials. More specifically, the present invention relates to an enclosure having walls, a roof, doors and a floor made from blow molded plastic materials.
BACKGROUND OF THE INVENTION
Utility sheds are a necessity for lawn and garden maintenance, as well as general all-around home storage space. Typically, items such as lawn mowers, garden tillers, snow blowers, wheel barrows, shovels, rakes, brooms and the like consume a great deal of floor space in a garage. This results in the homeowner parking his/her vehicles outside of the garage.
The prior art has proposed a number of different storage buildings or utility sheds assembled from a kit which include a plurality of blow molded or extruded plastic panels and connectors. These kits are readily assembled by a homeowner to form storage structures or utility sheds of various sizes. These structures are generally suitable for the storage of hand tools and smaller lawn equipment. Typically, these kits require extruded metal or plastic connector members having a specific cross-sectional geometry which facilitates an engagement between the connector members and one or more of the blow molded plastic panels having a complimentary edge configuration.
A particularly common structure for the connector members is the I-beam cross section. The I-beam defines free edge portions of the connector member which fit within approximately dimensioned and located slots in the panel members. U.S. Pat. No. D-371,208 teaches a corner extrusion for a building sidewall that is representative of the state of the art I-beam connector members. The I-beam sides of the connector engage with the peripheral edge channels of a respective wall panel, and thereby serve to join such panels together at right angles. Straight or in-line versions of the connector members are also included in the kits to join panels in a coplanar relationship to create walls of varying length.
Extruded components generally require hollow longitudinal conduits for strength. Due to the nature of the manufacturing process, the conduits are difficult to extrude in long sections for structural panels. Thus, the panels require connectors to achieve adequate height for utility shed walls. A common structure for connecting extruded members has a center I-beam with upper and lower protrusions for engaging the conduits. However, wall panels utilizing connectors are vulnerable to buckling under loads and may have an aesthetically unpleasing appearance. Moreover, roof loads from snow and the like may cause such walls to bow outwardly due to the clearances required between the connectors and the internal bores of the conduits. U.S. Pat. No. 6,250,022 discloses an extendable shed utilizing side wall connector members representing the state of the art. The connectors have a center strip with hollow protrusions extending from its upper and lower surfaces along its length. The protrusions are situated to slidably engage the conduits located in the side panel sections to create the height required for utility shed walls.
The aforementioned systems can also incorporate roof and floor panels to form a freestanding enclosed structure such as a utility shed. U.S. Pat. Nos. 3,866,381; 5,036,634; and 4,557,091 disclose various systems having inter-fitting panel and connector components. Such prior art systems, while working well, have not met all of the needs of consumers to provide the structural integrity required to construct larger sized structures. Larger structures must perform differently than smaller structures. Larger structures require constant ventilation in order to control moisture within the structure. Large structures must also withstand larger wind and snow loads compared to smaller structures. Paramount to achieving these needs is a panel system which eliminates the need for extruded connectors to create enclosure walls which resist panel separation, buckling and racking, and a roof system which allows ventilation while preventing weather infiltration. A further problem is that the walls formed by the panels must tie into the roof and floor in such a way as to unify the entire structure. Also, from a structural standpoint, the structure should include components capable of withstanding the increased wind, snow and storage loads required by larger structures. From a convenience standpoint, a door must be present which can be readily installed after assembly of the wall and roof components. The door must also be comparable with the side walls and provide ready access to the interior of the structure. Also from a convenience standpoint, the structure should permit natural as well as artificial lighting. The structure should be aesthetically pleasing in appearance to blend in with the surrounding structures.
There are also commercial considerations that must be satisfied by any viable structure assembly system or kit; considerations which are not entirely satisfied by the state of the art products. The structure must be formed from relatively few components which are inexpensive to manufacture by conventional techniques. The enclosure must also be capable of being packaged and shipped in a knock-down state. In addition, the system or kit must be modular and facilitate the creation of a family of enclosures that vary in size but which share common, interchangeable components.
Finally, there are ergonomic needs that an enclosure system must satisfy in order to achieve acceptance by the end user. The system must be easily and quickly assembled using integrally formed connectors requiring minimal hardware and tools. Further, the system must not require excessive strength to assemble or include heavy component parts. Moreover, the system must assemble together in such a way so as not to detract from the internal storage volume of the resulting enclosure, or otherwise negatively affect the utility of the structure.
SUMMARY OF THE INVENTION
The present invention provides a system or kit which includes plastic components which can be readily assembled to form a structure with the use of a minimal number of tools. The components are precut so that measurements and cutting of the component materials are eliminated. This leads to a savings in wasted materials. The components are readily assembled using conventional fasteners and simple hand tools. The components have preformed notches and tabs in order to facilitate assembly of the components without the requirement for measurements. This assures that the components will be assembled correctly and eliminates the opportunity for inaccurate measurements and incorrect assembly. The enclosure is provided with a sliding roof panel and pivoting doors which permit easy access to the interior of the enclosure.
Accordingly, it is an objective of the present invention to provide a system or kit for assembly of a utility enclosure which utilizes preformed plastic panels that permit ease of assembly of the utility enclosure.
It is a further objective of the present invention to provide a utility enclosure system or kit which includes a sliding roof panel and pivoting doors that permit easy access to the interior of the enclosure.
It is yet another objective of the present invention to provide a utility enclosure system or kit wherein the panel members include integrated connectors which accommodate plastic formation of the panel components for increased structural integrity.
It is a still further objective of the present invention to provide a utility enclosure system or kit which utilizes structural corner assemblies for increased enclosure rigidity.
It is still another objective of the instant invention to provide a utility enclosure system or kit which utilizes interlocking bosses and pockets to secure wall panels to a floor.
It is still another objective of the instant invention to provide a utility enclosure system or kit which utilizes floor components which interlock together for structural stability and the prevention of incursion of water into the enclosure.
Other objects and advantages of this invention will become apparent from the following description taken in conjunction with any accompanying drawings wherein are set forth, by way of illustration and example, certain embodiments of this invention. Any drawings contained herein constitute a part of this specification and include exemplary embodiments of the present invention and illustrate various objects and features thereof.
BRIEF DESCRIPTION OF THE FIGURES
FIG. 1 is a front perspective view of the present invention;
FIG. 2 is one of the floor panels;
FIG. 3 is a right wall side front panel;
FIG. 4 is a right wall side rear panel;
FIG. 5 is a rear panel;
FIG. 6 is a left side wall rear panel;
FIG. 7 is a left side wall front panel;
FIG. 8 is a left door;
FIG. 9 is a right door;
FIG. 10 is a perspective of the floor panels prior to assembly;
FIG. 11A is a perspective view of the assembled floor panels;
FIG. 11B is a view of the fasteners used to assemble the floor panels;
FIG. 12A is a perspective view of a right side wall panel and the floor panels;
FIG. 12B is a detail of the right side wall panel and floor panel connection;
FIG. 13A is a perspective view of a right side wall panel and the floor panels;
FIG. 13B is a detail of the right side wall panel and floor panel connection;
FIG. 14A is a perspective view of the right side wall panels secured together and secured to the floor panels;
FIG. 14B is a view of the fasteners used to secure the right side wall panels together;
FIG. 15 is a perspective view of the rear panel being secured to the floor panels;
FIG. 16 is a perspective view of the right side panels and rear panel assembled;
FIG. 17A is a perspective view of a left side panel being secured to the rear panel and floor panels;
FIG. 17B is a detail of the left side wall panel and floor panel connection;
FIG. 18A is a perspective view of a left side wall panel being secured to the floor panels;
FIG. 18B is a detail of the left side wall panel and floor panel connection;
FIG. 19 is a perspective view of the left side wall panels in their assembled positions;
FIG. 20A is a perspective view of a roof guide installed on the left side wall panels;
FIG. 20B is perspective view of an inner roof guide;
FIG. 21A is a perspective view of a roof support being installed;
FIG. 21B is a detail of the roof support and side wall panel connection;
FIG. 22A is a perspective view of a roof panel installed on the side wall panels;
FIG. 22B is a detailed view of the roof support, roof panel connection;
FIG. 23A is a view of the location of the rear panel to roof retainer clips;
FIG. 23B is a detail of the connection of the rear panel to roof retainer clips;
FIG. 24 is a perspective view of the connection of the roof guide to roof panel connection;
FIG. 25 is a perspective view of the sliding roof panel;
FIG. 26A is a perspective view of the sliding roof panel installed;
FIG. 26B is a perspective view of a roof guide installed on the sliding roof panel;
FIG. 27A is a perspective view of the location of the roof clips;
FIG. 27B is a view of a roof clip being installed;
FIG. 27C is a view of an installed roof clip;
FIG. 27D is a side view of a roof clip;
FIG. 28 is a perspective view of the enclosure with a roof panel in the back or open position;
FIG. 29 is a perspective view of a left door panel being installed;
FIG. 30A is a view of the left door panel installed;
FIG. 30B is a view of the left upper door retainer;
FIG. 31A is a view of a left lower door retainer installed;
FIG. 31B is a view of a left lower door retainer being installed;
FIG. 31C is a view of the location of the left lower door retainer;
FIG. 32A is a view of the location of the left upper door retainer;
FIG. 32B is a view of the fasteners used to install the left lower door retainer;
FIG. 33 is a perspective view of the assembled enclosure with the roof panel in the back or open position;
FIG. 34A is a view of the handles installed on the doors of the enclosure;
FIG. 34B is a view of the handle to door connection; and
FIG. 35 is a view of a lock used to secure the enclosure closed.
DETAILED DESCRIPTION OF THE INVENTION
While the present invention is susceptible of embodiment in various forms, there is shown in the drawings and will hereinafter be described a presently preferred, albeit not limiting, embodiment with the understanding that the present disclosure is to be considered an exemplification of the present invention and is not intended to limit the invention to the specific embodiments illustrated.
FIGS. 1-35 , which are now referenced, illustrate perspective and exploded views of a system or kit for the assembly of a preferred embodiment of the present invention. A utility enclosure or shed is generally illustrated at 10 in FIG. 1 . The enclosure or shed 10 includes a right side wall 12 , a left side wall 14 , a rear wall 16 , doors 18 , a floor 20 , and a roof 22 . The right side wall includes a right side front wall 24 and a right side rear wall 26 ( FIGS. 3 and 4 ). The left side wall includes a left side front wall 28 and a left side rear wall 30 ( FIGS. 6 and 7 ). A rear wall is identified as 32 in FIG. 5 . The doors include a left door 34 and a right door 36 ( FIGS. 8 and 9 ). The floor includes a front floor panel 38 and a rear floor panel 40 ( FIG. 10 ). The roof includes a front roof panel 42 and a rear roof panel 44 ( FIG. 25 ). These panels are preferably formed from molded plastic.
The floor includes at least two floor panels 38 and 40 which are secured to each other to form the floor of the enclosure. The floor panels 38 and 40 are secured together in an overlapping connection as illustrated in FIGS. 11A and 11B . Rear floor panel 40 includes a projection or lip 42 which extends along a width of the panel. This lip 42 overlaps a projection or lip 44 , which extends along a width of the panels, in an interlocking relation on the front floor panel ( FIG. 11B ). A plurality of fasteners 46 secure the front and rear floor panels together, as illustrated in FIG. 11B . These fasteners are preferably machine screws. However, other screws and/or fasteners can be employed.
The right side wall 12 includes a right side wall front panel 24 secured to a right side wall rear panel 26 . First, the right side wall front wall panel 24 is secured to the front floor panel 38 in the manner illustrated in FIG. 12A . The right side wall front panel includes at least three bosses 48 located at a lower portion of the panel. These bosses 48 engage corresponding sockets (not shown) in the floor panel. The right side wall front panel 24 is placed on an edge of the floor panel 38 . The bosses 48 then engage corresponding sockets and the panel 24 is slid rearward. This motion interlocks the bosses into the corresponding sockets. The right side wall rear panel 26 is installed on the rear floor panel 40 in a manner similar to the installation of the right side wall front panel 24 . The panel 26 includes at least three bosses 50 located on a lower portion of the panel. These bosses 50 engage corresponding sockets (not shown) on the floor panel 40 . The right side wall rear panel 26 is placed on an edge of the floor panel 40 . The bosses 50 then engage corresponding sockets and the panel 26 is slid forward. This motion interlocks the bosses into the corresponding sockets. The right side wall front and rear panels are secured to each other with fasteners 52 at the locations indicated illustrated in FIG. 14A . As can be seen in FIG. 14A , the rear portion of right side wall rear panel includes a curved wall portion 54 . This curved wall portion 54 forms a curved transition between the right side wall and the rear wall 32 .
The rear wall panel 32 includes at least two bosses 56 ( FIG. 15 ). These bosses are located on a lower portion of the rear wall panel. These bosses 56 engage corresponding sockets (not shown) on the floor panel 40 . The rear wall rear panel 32 is placed on an edge of the floor panel 40 . The bosses 56 then engage corresponding sockets in the floor panel 40 and the rear wall panel 32 is slid either to the left or to the right. This motion interlocks the bosses into the corresponding sockets. Fasteners, similar to fasteners 52 , are used to secure the rear wall panel 32 to the right side wall rear panel 26 , as illustrated at 58 in FIG. 16 .
The left side wall 14 includes a left side wall front panel 30 secured to a left side wall rear panel 28 . First, the left side wall rear wall panel 28 is secured to the rear floor panel 40 in the manner illustrated in FIG. 17A . The left side wall rear panel includes at least three bosses 60 located at a lower portion of the panel ( FIGS. 17A and B). These bosses 60 engage corresponding sockets (not shown) in the floor panel. The left side wall rear panel 28 is placed on an edge of the floor panel 40 . The bosses 60 then engage corresponding sockets and the panel 28 is slid forward. This motion interlocks the bosses into the corresponding sockets. The left side wall front panel 30 is installed on the front floor panel 38 in a manner similar to the installation of the left side wall rear panel 28 . The panel 30 includes at least three bosses 62 located on a lower portion of the panel. These bosses 62 engage corresponding sockets (not shown) on the floor panel 38 . The left side wall front panel 30 is placed on an edge of the floor panel 30 . The bosses 62 then engage corresponding sockets and the panel 30 is slid forward. This motion interlocks the bosses into the corresponding sockets. The left side wall front and rear panels are secured to each other with fasteners, similar to fasteners 52 , at the locations 64 indicated in FIG. 19 . As can be seen in FIG. 19 , the rear portion of left side wall rear panel includes a curved wall portion 66 . This curved wall portion 66 forms a curved transition between the right side wall and the rear wall 32 . Fasteners, similar to fasteners 52 , are used to secure the rear wall panel 32 to the left side wall rear panel 28 , as illustrated at 68 in FIG. 19 .
The roof includes a front roof panel 42 and a rear roof panel 44 ( FIG. 25 ). The rear roof panel 44 is secured to the right, left and rear wall panels in a fixed position. The front roof panel 42 is movable between an open position ( FIG. 22A ) and a closed position ( FIG. 1 ). The roof panels 42 and 44 are convexly curved along a traverse cross section, thereby permitting rain and other weather elements to shed off of the roof A roof guide 68 is secured to an upper portion of both the front and rear left side wall panels 30 and 28 ( FIG. 20A ). Fasteners 70 are used to secure roof guide 68 to the side wall panels. Fasteners 70 are similar to fasteners 52 . Roof guide 68 also provides an additional device or means to secure the front and rear left side wall panels to each other. A similar roof guide (not shown) is secured to the upper portions of the front and rear right side wall panels in the same manner as roof guide 68 . An inner roof guide 72 is slidably secured between the roof guide 68 and the left side wall front panel 30 ( FIG. 20B ). Another inner roof guide (not shown) is secured between the other roof guide and the right side wall front panel. Both inner roof guides are secured to the front roof panel 42 . The inner roof guides and roof guides allow the front roof panel to slidably move between an open and a closed position.
A roof support 74 is secured between the roof guides ( FIGS. 21A and 22A ). A slot 76 is formed on both the roof supports into which respective ends of the roof support 74 is inserted. The front of the rear roof panel 44 is placed onto the roof support 74 ( FIGS. 22A and B). The sides of the rear roof panel 44 are secured to the roof guides 68 with fasteners 76 , as illustrated in FIG. 24 . The other side of the rear roof panel 44 is also secured to a roof guide (not shown) with fasteners 76 in a similar manner. The rear end portion of the rear roof panel 44 is secured to the rear wall panel with retainers 78 and fasteners 80 ( FIG. 23B ). All of these connections secure the rear roof panels 44 to the right, left and back wall panels in a fixed position.
The front roof panel 42 is secured to the inner roof guides 72 using fasteners 82 ( FIG. 26B ). The inner roof guides are preferably secured to a forward portion of the front roof panel 42 as indicated at 84 in FIG. 26A . When the front roof panel 42 is in the closed position ( FIG. 1 ) the rear portion of the panel 42 is secured to the front portion of rear roof panel 44 by at least two clips 84 ( FIGS. 27A-D ). As illustrated in FIGS. 27A-C there is a groove or slot 86 on both sides of a rear portion of the front roof panel 42 and a groove or slot 88 on both sides of a front portion of the rear roof panel 44 . When the roof panels are in the closed position, the lower portion of clip 84 is first placed into groove or slot 88 and then pivoted upward to be placed into groove or slot 86 . This connection securely locks the front roof panel 42 to the rear roof panel, thereby preventing the roof panels from separating and preventing access to the interior of the enclosure. When it is desired to open the roof, the clips 84 are removed and the front roof panel 42 is slid rearwardly, as illustrated in FIG. 28 .
FIGS. 29-32 illustrated the manner in which the left door panel 34 is installed on the enclosure. The left side wall front panel 30 includes at least three connectors 90 , 92 and 94 which function as hinges. These connectors, 90 - 94 , operatively cooperate with pins 96 , 98 , and 100 on the left door panel 34 to allow the left door panel to be moved from a closed position to an open position and back again. Pin 96 is secured in connector 90 using a securing member 102 ( FIG. 30 A). A fastener 104 secures the securing member 102 to the left side wall front panel 30 . Pins 98 are slid into connector 92 and frictionally held therein. Pin 100 is secured in connector 94 using a securing member 106 ( FIGS. 31A-C and 32 A). Fasteners 108 secure the securing member 106 to the left side wall front panel 30 and the floor 38 ( FIG. 32 B). The right door panel 36 is secured to the right side wall front panel 26 and the floor panel 38 in the same manner as of the left door panel 34 . A plurality of handles 110 are secured to the upper portions of door panels 34 and 36 using fasteners 112 , as illustrated in FIGS. 34A and B. A securing or locking element 114 is provided on the front roof panel 42 ( FIG. 35 ). A securing or locking element 116 is provided on the right door panel 36 ( FIG. 35 ). A lock 118 can securely connect elements 114 and 116 together, thus preventing unauthorized entry into the enclosure 10 .
All patents and publications mentioned in this specification are indicative of the levels of those skilled in the art to which the invention pertains. All patents and publications are herein incorporated by reference to the same extent as if each individual publication was specifically and individually indicated to be incorporated by reference.
It is to be understood that while a certain form of the invention is illustrated, it is not to be limited to the specific form or arrangement herein described and shown. It will be apparent to those skilled in the art that various changes may be made without departing from the scope of the invention and the invention is not to be considered limited to what is shown and described in the specification and any drawings/figures included herein.
One skilled in the art will readily appreciate that the present invention is well adapted to carry out the objectives and obtain the ends and advantages mentioned, as well as those inherent therein. The embodiments, methods, procedures and techniques described herein are presently representative of the preferred embodiments, are intended to be exemplary and are not intended as limitations on the scope. Changes therein and other uses will occur to those skilled in the art which are encompassed within the spirit of the invention and are defined by the scope of the appended claims. Although the invention has been described in connection with specific preferred embodiments, it should be understood that the invention as claimed should not be unduly limited to such specific embodiments. Indeed, various modifications of the described modes for carrying out the invention which are obvious to those skilled in the art are intended to be within the scope of the following claims. | The present invention provides a system or kit which includes plastic components which can be readily assembled to form a structure with the use of a minimal number of tools. The components are precut so that measurements and cutting of the component materials is eliminated. This leads to a savings in wasted materials. The components are readily assembled using conventional fasteners and simple hand tools. The components have preformed notches and tabs in order to facilitate assembly of the components without the requirement for measurements. This assures that the components will be assembled correctly and eliminates the opportunity for inaccurate measurements and incorrect assembly. The enclosure is provided with a sliding roof panel and pivoting doors which permit easy access to the interior of the enclosure. | 4 |
BACKGROUND OF THE INVENTION
This invention relates to a dispenser device for use with automatic washing machines. More particularly, this invention is directed to an automatic siphon type dispenser for dispensing liquid into the wash water.
Clothes washing machines of the automatic type include a clothes basket into which the clothes to be washed are placed. In top loading machines, which are the kind having a vertically oriented basket with a hinged, top loading door, the clothes are loosely placed in the basket around a centrally disposed agitator. Typically, the agitator tapers from a base at the bottom of the clothes basket to a generally frustoconical end or projection spaced from the top door when in the closed or horizontal position. A plurality of agitator blades are frequently found on the sides of the agitator for disturbing the wash water and thereby removing dirt and other contaminants from the clothes.
Commonly, these automatic washing machines have control mechanisms for establishing a sequence of washing cycles. The general sequence is washing, extracting by spinning, rinsing and then extracting by spinning again. Of course, complex cycles may be used as warranted.
After the machine is loaded with clothes, and the lid closed, the first cycle of washing begins with the slow filling of the wash basket with water. This filling takes a period of several minutes. Usually, a soap or detergent which may be of granular form is used in the washing operation. The soap or detergent is generally placed in the wash basket over the clothes prior to the closing of the lid and the initiation of the washing cycles. Frequently, however, it is desirable to also add additional additives such as water softeners, fabric softeners, bleach, etc. to the machine. However, these additives should be placed in the machine after the basket has filled with water in order to ensure that the full concentration of such substances is not brought into intimate contact with the clothes.
Without some sort of automatic dispensing mechanism, this would require a monitoring of the machine and then a manual reopening of the lid after the water has filled the basket but before agitation has begun.
Some attempts to solve the problem thus posed of providing a dispenser which will insert a liquid additive to the clothes basket of a washing machine at the time after the washing cycle has started are extant in the prior art. Examples of these are found in U.S. Pat. No. 2,991,911 to Spain; U.S. Pat. No. 2,534,014 to Gayring et al; and U.S. Pat. No. 3,233,794 to Sisler. However, these prior art attempts have certain deficiencies which do not make them completely suitable for solving the problem. One deficiency with some of these prior art devices is that they are rather complex and therefore costly. They further require attachment and some integration into the workings of the washing machine with which they are used, and therefore materially add to cost. These devices typically may not be merely added to an existing washing machine but must be built into the machine at the factory, thus making them virtually inapplicable to the millions of already existing washing machines that have been sold without such automatic dispenser capability.
SUMMARY AND OBJECTS OF THE INVENTION
It is the primary object of this invention to provide an automatic dispenser for use in washing machines.
It is a further object of this invention to provide an automatic dispenser of simple construction, and having few, if any, moving parts.
It is a further object of this invention to provide an automatic liquid dispenser for washing machines which is self-energizing by means of agitator action.
It is a further object of this invention to provide an automatic dispenser for washing machines that dispenses a liquid contained therein into the machine a desired period of time after the initiation of machine operation.
It is a still further object of this invention to provide such an automatic dispenser which is adapted for use on many different types of machines.
In form, the dispenser of this invention is of torroidal or donut shape, and thereby adapted to be mounted on the end of an agitator typically found in a top loading machine. The dispenser includes a measuring chamber for containing liquid such as water softeners, fabric softeners, bleach, soap, detergent, etc. By making the dispenser of clear plastic material and having indicia thereon, the precise amount of liquid to be dispensed may be easily loaded into the dispenser. Facilitating the loading is an annular depression in the top of the dispenser body having openings therein leading to the measuring chamber. Dispensing and timing means in the form of a double siphon arrangement operate to dispense the liquid into the machine. The double siphon arrangement comprises a first siphon leading to a timing chamber and a second siphon leading to a measuring chamber. The mechanism includes the filling of the timing chamber with liquid to be dispensed after which the timing chamber siphon fills and begins to empty the fluid in the timing chamber into a discharge tube from whence it passes through a shuttle valve type through a discharge opening into the clothes basket. A second siphon tube empties the remaining liquid from the measuring chamber. In an alternate embodiment, only a single siphon tube is used.
A generally frustoconical adapter having an internal radial vane permits mounting the dispenser on various washer agitators. The mounting ring includes internal, radially spaced vanes and has an elastomeric gripping band thereon, for securely mounting the inner core of the dispenser to the agitator. The outer wall of the agitator mates with an accommodating inner bore of the dispenser.
Further and other objects and advantages of this invention will become more readily apparent from a review of the following disclosure and accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a front elevational isometric view partially cut away of a washing machine of the top loading type and having a dispenser of the instant invention mounted therein.
FIG. 2 is a side elevational exploded view of the dispenser and mounting ring or adapter, both in partial cross section;
FIG. 3 is a top view partially cut away of the dispenser of FIG. 2;
FIG. 4 is a view similar to FIG. 3 showing the dispenser advanced as during agitation;
FIGS. 5 through 8 show the double siphon system of the instant invention in various sequential stages of operation;
FIG. 9 is a graphic illustration of the double siphon system operation;
FIG. 10 is a view of an alternate embodiment of the double siphon;
FIG. 11 is a view of an alternate embodiment of the dispenser and having a single siphon system; and,
FIG. 12 is a top plan view of the dispenser of FIG. 11, partially cut away.
DETAILED DESCRIPTION
Turning to FIG. 1, there is shown generally at 10 a washing machine having a top opening 11 selectively closable by means of a hinged door 12. A generally drum shaped clothes basket 13 is mounted in the machine about a vertical axis and has a clothes chamber 14 therein for receiving clothes through top opening 11.
Also located within the clothes basket on the vertical axis is a centrally disposed agitator 15. The agitator includes a plurality of agitator vanes or panels 16 equally spaced around the periphery thereof. The agitator itself includes a generally disc-shaped base 17 transcending to a generally frustoconical post or free end portion 18.
Removably mounted on the agitator post is a generally donut or torroidially shaped dispenser 19 as will be more fully described hereinafter. Like the post, the dispenser is positioned just within and spaced from the top of the door when in its closed position. Discharge tube 20 on the underside of dispenser 19 serves to distribute liquid to be dispensed into the wash water 21 as will also be described hereinafter.
Turning to FIG. 2, the dispenser and its means for mounting on the agitator post are shown. Mounting is accomplished by means of using an adapter or mounting ring 22. Mounting ring 22 has a generally frustoconical exterior wall 23 which is fittable in mating relation to accommodatingly shaped interior wall 24 of dispenser 19. Of course, if the agitator post is of the proper dimension, it may be directly fitted into the bore 25 formed by interior wall 24 in dispenser 19.
On the interior of the adapter of mounting ring 22 are located a plurality of vanes 26 in equally spaced relation. These vanes extend from inner wall 27 of adapter 22 radially inwardly to a point spaced from the central axis of the adapter. Slots 28 in the vanes serve to mount an elastic band 29 for the purpose of gripping the agitator post.
The adapter may be made of any convenient material, such as plastic. The elastic band may be made of any elastomeric material, such as rubber. The dispenser 19 itself can most effectively be constructed of clear plastic material. In this manner, the contents of the dispenser are always readily viewable which assists in filling, as will be hereinafter described. The dispenser 19 comprises a generally torroidal or donut shaped body which may be conveniently molded of pieces of plastic material. The dispenser body itself comprises a top 31 which may be lifted off of the bottom 32 as desired. The bottom defines an annular measuring chamber 33 with a radially outwardly positioned timing chamber 34 therearound. The measuring chamber includes a pair of spaced, generally vertical sidewalls 35, 36 joined by a sloping bottom wall 37. An annular trough 38 is formed at the juncture of sidewall 35 and bottom wall 37. An impact tube or conduit 39 leads from the trough 38 along the underside of bottom wall 37 between vertical wall 36 and vertical divider wall 40 of timing chamber 34. Timing chamber 34 includes a bottom wall 41 and an annular trough 42 at the juncture of wall 41 and vertical wall 40.
Filling of the measuring chamber 33 is facilitated by means of the annular funnel 43 formed by the intersection of sloping inner wall 44 of top 31 and the sidewall 45 of central projection 46 of the dispenser body 19. Top 31 is partially supported by three raised areas 47, two of which are shown in the Figure. These raised areas permit fluid to flow from annular funnel 43 into measuring chamber 33 for filling thereof. The filling of the chamber may be gauged by means of indicia 48 which may be cast or otherwise formed in the material of the dispenser as shown on interior wall 24. Since the dispenser is made of transparent material, these indicia may be easily viewed through top 31.
A dispensing and timing means in the form of a double siphon arrangement 49 serves to dispense the fluid through discharge tube 20 after a predetermined time has elapsed. Discharge tube 20 is of arcuate construction and having a closed end with a plurality of spaced, discharge ports or openings 9 on the radially outermost portion thereof to aid in dispersion of the fluid. Acceleration forces provided by agitation cause a pressure buildup in tube 20 so as to force the liquid to be dispersed through ports 9 and thence into the wash water (not shown).
As shown in FIGS. 3 and 4, the double siphon arrangement comprises a siphon tube 50 primarily located underneath measuring chamber 33. A first measuring chamber siphon 51 leads from measuring chamber 33 to siphon tube 50. A second timing chamber siphon 52 leads from timing chamber 34 to a point in siphon tube 50 which leads into centrifugally actuable shuttle type pump 53. As may be seen, the open or inlet end 54 of siphon 51 is located within annular trough 38. Since wall 37 (see FIG. 1) slopes towards this annular trough, such location permits the full draining of the measuring chamber by the double siphon arrangement as will be more fully described hereinafter.
As seen in these Figures, one end 58 of impact tube 39 is angled so that agitator action causes tube end 58 to move relative to the contained liquid within measuring chamber 33. This causes the liquid to rise in impact tube 39 and be discharged into timing chamber 34 over a period of time through outlet opening 59 in impact tube 39.
FIG. 5 shows the timing chamber just prior to filling by the impact tube. In one direction of rotation of the agitator, the impact tube impacts the liquid causing it to enter the tube and forcing it to rise. Outlet opening 59 is positioned to be above the maximum fill level in the timing chamber. Liquid entering the impact tube under impact pressure rises and moves outwardly with centrifugal force aiding its flow.
Since agitator action is intermittent, the flow into the timing chamber is also intermittent. Nevertheless, the chamber fills at a relatively constant rate. In order to ensure that the open end 58 of the impact tube is not uncovered by the centrifugal force of agitator action, a plurality of small vanes 60 are spaced around the periphery of the chamber at the juncture between verticall wall 36 and horizontal wall 37.
A higher liquid levels, the same vanes tend to drive liquid in the direction of rotation, thereby reducing the impact pressure at the tube end 58. This tends to reduce the variation of flow rate in impact tube 39 otherwise caused by changes in fill level.
As the timing chamber 34 fills at a relatively constant rate, in a predetermined time, the rise in liquid level will fill timing chamber siphon 52 and outflow will begin, as best seen in FIG. 6. This outflow will continue because of siphon action until the timing chamber is empty, as best seen in FIG. 7.
The liquid flowing out of siphon 52 into siphon tube 50 is impeded by shuttle pump 53 as the agitator rotates counterclockwise, so that flow is momentarily diverted inwardly towards measuring chamber siphon 51. Upon reversal of agitator motion, centrifugal force causes slug 57 to move in the opposite direction causing a partial vacuum in siphon tube 50, thereby causing siphon 51 to fill. Flow through siphon 51 continues intermittently until the measuring chamber is emptied, as seen in FIG. 8. As may be appreciated by viewing FIG. 9, the initial time delay from the start of the washing machine to t1 to the start of agitator action at t2 plus the filling of the timing chamber to t3 results in a predetermined desired time delay for emptying of liquid into the washing machine. As may be appreciated from the graph of FIG. 9, both chambers then empty from time t3 to t4 in a simultaneous manner. The siphons are positioned so that centrifugal force does not trigger them prematurely.
As seen in FIG. 10, an alternate embodiment of the double siphon arrangement is possible wherein the pump is replaced by the constriction 53'. The constriction in the tube serves the same purpose as in the previously described shuttle type pump. As also seen in this Figure, the discharge from the siphon may alternatively be simply an opening 9' in the end of tube 20.
Turning to FIGS. 11 and 12, a single siphon version is also possible which eliminates the measuring chamber siphon. With this embodiment, a single siphon 52' is used to transfer liquid from timing chamber 34' through discharge tube 20'. As with the first embodiment described above, the timing chamber is filled by means of impact tube 39' which fills the timing chamber in response to the reciprocating motion imparted to dispenser 19' by agitator action.
The time delay is created by the time required to fill the timing chamber to the point where siphon 52' begins to operate. The operation continues until all of the fluid from measuring chamber 33' has been transferred into timing chamber 34' and thence is expelled through discharge tube 20'.
It is believed that the operation of the dispenser is sufficiently clear from the above description. Nevertheless, the operation will be further described as follows. Having reference to FIG. 2, the mounting of adapter 22 is accomplished by forcing it over the agitator post, the dimensions of which vary with different brands of washing machines. Inward facing vanes 26 of mounting ring 22 are flexible so as to be capable of deflection. Elastic band 29 acts as a spring biasing means to urge the blades into the small center space. With the ring 22 inserted into bore 24 of dispenser 19, the dispenser may be forced down with a twisting motion so that the blades bend to admit the diameter of the agitator post that it is forced against. Vanes 26 will deflect uniformly, thereby centering the dispenser. Elastic band 29 will be expanded to maintain sufficient force for the dispenser to follow agitator motion.
Liquid to be dispensed is then poured into dispenser 19 through annular funnel 43 to the desired fill level as measured by indicia 48. Indicia 48 may conveniently provide cup and fractional cup indication.
The washing machine lid is then closed and the machine cycle started by means of actuating the machine control (not shown). The dispenser will then dispense fluid into the wash water a predetermined time after initiation of agitator action.
It is to be understood that the foregoing description is merely illustrative of the preferred and alternate embodiments of the invention and that the scope of the invention is not to be limited thereto, but is to be determined by the scope of the appended claims. | A dispenser for use on an agitator-type washing machine is provided. Means are provided for mounting the dispenser on various machines by means of an adapter. The dispenser has a body of generally cylindrical shape which may be mounted on the agitator. The dispenser includes a measuring chamber for containing a volume of liquid such as bleach, soap, etc. Also included are dispensing and timing means for dispensing the liquid in the chamber a predetermined time after the initiation of agitator action. In this manner, liquid is not dispensed until after filling of the machine has occurred. In the first embodiment, the dispensing and timing means includes a double siphon arrangement. In a second embodiment, a single siphon arrangement is used. | 3 |
This invention relates to speech analysis and more particularly to linear prediction speech pattern analyzers.
Linear predictive coding (LPC) is used extensively in digital speech transmission, speech recognition and speech synthesis systems which must operate at low bit rates. The efficiency of LPC arrangements results from the encoding of the speech information rather than the speech signal itself. The speech information corresponds to the shape of the vocal tract and its excitation and as is well known in the art, its bandwidth is substantially less than the bandwidth of the speech signal. The LPC coding technique partitions a speech pattern into a sequence of time frame intervals 5 to 20 milliseconds in duration. The speech signal is quasi-stationary during such time intervals and may be characterized by a relatively simple vocal tract model specified by a small number of parameters. For each time frame, a set of linear predictive parameters are generated which are representative of the spectral content of the speech pattern. Such parameters may be applied to a linear filter which models the human vocal tract along with signals representative of the vocal tract excitation to reconstruct a replica of the speech pattern. A system illustrative of such an arrangement is described in U.S. Pat. No. 3,624,302 issued to B. S. Atal, Nov. 30, 1971, and assigned to the same assignee.
Vocal tract excitation for LPC speech coding and speech synthesis systems may take the form of pitch period signals for voiced speech, noise signals for unvoiced speech and a voiced-unvoiced signal corresponding to the type of speech in each successive LPC frame. While this excitation signal arrangement is sufficient to produce a replica of a speech pattern at relatively low bit rates, the resulting replica has limited intelligibility. A significant improvement in speech quality is obtained by using a predictive residual excitation signal corresponding to the difference between the speech pattern of a frame and a speech pattern produced in response to the LPC parameters of the frame. The predictive residual, however, is noise-like since it corresponds to the unpredicted portion of the speech pattern. Consequently, a very high bit rate is needed for its representation. U.S. Pat. No. 3,631,520 issued to B. S. Atal, Dec. 28, 1971, and assigned to the same assignee discloses a speech coded system utilizing predictive residual excitation.
An arrangement that provides the high quality of predictive residual coding at a relatively low bit rate is disclosed in U.S. Pat. 4,472,832 issued to B. S. Atal et al Sept. 18, 1984 and assigned to the same assignee and in the article, "A new model of LPC excitation for producing natural sounding speech at low bit rates", appearing in the Proceedings of the International Conference on Acoustics, Speech and Signal Processing, Paris, France, 1982, pp. 614-617. As described therein, a signal corresponding to the speech pattern for a frame is generated as well as a signal representative of its LPC parameters responsive speech pattern for the frame. A prescribed format multipulse signal is formed for each successive LPC frame responsive to the differences between the frame speech pattern signal and the frame LPC derived speech pattern signal. Unlike the predictive residual excitation whose bit rate is not controlled, the bit rate of the multipulse excitation signal may be selected to conform to prescribed transmission and storage requirements. In contrast to the predictive vocoder type arrangement, intelligibility is improved, partially voiced intervals are accurately encoded and classification of voiced and unvoiced speech intervals is eliminated.
It has been observed that a multipulse excitation signal having approximately eight pulses per pitch period provides adequate speech quality at a bit rate substantially below that of the corresponding predictive residual. Speech pattern pitch, however, varies widely among individuals. More particularly, the pitch found in voices of children and adult females is generally much higher than the pitch for voices of adult males. As a result, the bit rate for multipulse excitation signals increases with voice pitch if high speech quality is to be maintained for all speakers. Thus, the bit rate in speech processing using multipulse excitation for adequate speech quality is a function of speaker pitch. It is an object of the invention to provide improved speech pattern coding with reduced excitation signal bit rate that is substantially independent of voice pitch.
BRIEF SUMMARY OF THE INVENTION
The foregoing object is achieved through removal of redundancy in the prescribed format multipulse excitation signal. A certain redundancy is found in all portions a speech pattern and is particularly evident in voiced portions of the speech pattern. Thus, signals indicative of excitation signal redundancy over several frames of speech may be coded and utilized to form a lower bit rate (redundancy reduced) excitation signal from the coded excitation signal. In forming a replica of the speech pattern, the redundancy indicative signals are combined with the redundancy reduced coded excitation signal to provide the appropriate excitation. Advantageously, the transmission facility bit rate and the coded speech storage requirements may be substantially reduced.
The invention is directed to a predictive speech pattern coding arrangement in which a speech pattern is sampled and the samples are partitioned into successive time frames. For each frame, a set of speech parameter signals are generated responsive to the frame sample signals and a signal representative of differences between the frame speech pattern and the speech parameter signal representative pattern is produced responsive to said frame predictive parameter signals and said frame speech pattern sample signals. A first signal is formed responsive to said frame speech parameter signals and said frame differences signal. A secnd signal is generated responsive to said frame speech parameter signals, and a third signal is produced that is representative of the similarities between the speech pattern of the frame and the speech pattern of preceding frames. Jointly responsive to the first, second and third signals, a prescribed format signal corresponding to the frame differences signal is formed. The second signal is modified responsive to said prescribed format signal.
According to one aspect of the invention the speech parameter signals are predictive parameter signals and the frame differences signal is a predictive residual signal.
According to another aspect of the invention, at least one signal corresponding to the frame to frame similarities is formed for each frame and a replica of the frame speech pattern is generated responsive to the prescribed format signal, the frame to frame similarity signals and the prediction parameter signals of the frame.
DESCRIPTION OF THE DRAWING
FIG. 1 depicts a block diagram of a speech coding arrangement illustrative of the invention;
FIG. 2 depicts a block diagram of processing circuit arrangement that may be used in the arrangement of FIG. 1.
FIGS. 3 and 4 show flow charts that illustrate the operation of the processing circuit of FIG. 2;
FIG. 5 shows a speech pattern synthesis arrangement that may be utilized as a decoder for the arrangement of FIG. 1; and
FIG. 6 shows waveforms illustrating the speech processing according to the invention.
DETAILED DESCRIPTION
FIG. 1 depicts a general block diagram of a speech processor that illustrates the invention. In FIG. 1, a speech pattern such as a spoken message is received by microphone transducer 101. The corresponding analog speech signal therefrom is band-limited and converted into a sequence of pulse samples in filter and sampler circuit 113 of prediction analyzer 110. The filtering may be arranged to remove frequency components of the speech signal above 4.0 KHz and the sampling may be at an 8.0 KHz rate as is well known in the art. The timing of the samples is controlled by sample clock SC from clock generator 103. Each sample from circuit 113 is transformed into an amplitude representative digital code in analog-to-digital converter 115. The sequence of digitally coded speech samples is supplied to predictive parameter computer 119 which is operative, as is well known in the art, to partition the speech signals into 10 to 20 ms frame intervals and to generate a set of linear prediction coefficient signals a k ,k=1,2, . . . ,p representative of the predicted short time spectrum of the N>>p speech samples of each frame. The speech samples from A/D converter 115 are delayed in delay 117 to allow time for the formation of speech parameter signals a k . The delayed samples are supplied to the input of prediction residual generator 118. The prediction residual generator, as is well known in the art, is responsive to the delayed speech samples and the prediction parameters a k to form a signal corresponding to the differences therebetween. The formation of the predictive parameters and the prediction residual signal for each frame shown in predictive analyzer 110 may be performed according to the arrangement disclosed in U.S. Pat. No. 3,740,476 issued to B. S. Atal June 19, 1973, and assigned to the same assignee or in other arrangements well known in the art.
While the predictive parameter signals a k form an efficient representation of the short time speech spectrum, the residual signal generally varies widely and rapidly over each interval and exhibits a high bit rate that is unsuitable for many applications. Waveform 601 of FIG. 6 illustrates a typical speech pattern over a plurality of frames. Waveform 605 shows the prescribed format multipulse excitation signal for the speech pattern of waveform 601 in accordance with the arrangements described in the aforrementioned patent application and article. As a result of the invention, the similarities between the excitation signal of the current frame and the excitation signals of preceding frames are removed from the prescribed format multipulse signal of waveform 605. Consequently, the pitch dependence of the multipulse signal is eliminated and the amplitude range of the multipulse signal is substantially reduced. After processing in excitation signal forming circuit 120, the redundancy reduced multipulse signal of waveform 610 is obtained. A comparison between waveforms 605 and 610 illustrates the improvement that is achieved. Waveform 615 shows a replica of the pattern of waveform 601 obtained using the excitation signal of waveform 610, the redundancy parameter signals and the predictive parameter signals.
The prediction residual signal d k and the predictive parameter signals a k for each successive frame are applied from circuit 110 to excitation signal forming circuit 120 at the beginning of the succeeding frame. Circuit 120 is operative to produce a redundancy reduced multielement excitation code EC having a predetermined number of bit positions for each frame and a redundancy parameter code γ,M* for the frame. Each excitation code corresponds to a sequence of 1≦i≦I pulses representative of the excitation function of the frame with multiframe redundancy removed to make it pitch insensitive. The amplitude β i and location m i of each pulse within the frame is determined in the excitation signal forming circuit as well as the γ and M* redundancy parameter signals so as to permit construction of a replica of the frame speech signal from the excitation signal when combined with the redundancy parameter signals, and the predictive parameter signals of the frame. The β i and m i signals are encoded in coder 131. The γ and M signals are encoded in coder 155. These excitation related signals are multiplexed with the delayed prediction parameter signals a' k of the frame in multiplexer 135 to provide a coded digital signal corresponding to the frame speech pattern.
In excitation signal forming circuit 120, the predictive residual signal d k and the predictive parameter signals a k of a frame are supplied to filter 121 via gates 122 and 124, respectively. At the beginning of each frame, frame clock signal FC opens gates 122 and 124 whereby the frame d k signal is applied to filter 121 and the frame a k signals are applied to filters 121 and 123. Filter 121 is adapted to modify signal d k so that the quantizing spectrum of the error signal is concentrated in the formant regions thereof. As disclosed in U.S. Pat. No. 4,133,976 issued to B. S. Atal et al, Jan. 9, 1979 and assigned to the same assignee, this filter arrangement is effective to mask the error in the high signal energy portions of the spectrum.
The transfer function of filter 121 is expressed in z transform notation as: ##EQU1## where ##EQU2## and ##EQU3##
Predictive filter 123 receives the frame predictive parameter signals a k from computer 119 and an excitation signal v(n) corresponding to the prescribed format multipulse excitation signal EC from excitation signal former 145. Filter 123 has the transfer function of Equation 1. Filter 121 forms a weighted frame speech signal y responsive to the predictive residual d k while filter 123 generates a weighted predictive speech signal y responsive to the multipulse excitation signal being formed over the frame interval in multipulse signal generator 127. The output of filter 121 is ##EQU4## where d k is the predictive residual signal from residual signal generator 118 and h n-k corresponds to the response of filter 121. The output of filter 123 is ##EQU5## Signals y(n) and y(n) are applied to frame correlation signal generator 125 and the current frame predictive parameters a k are applied to multiframe correlation signal generator 140.
Multiframe correlation signal generator 140 is operative to form a multiframe correlation component signal y p (n) corresponding to the correlation of the speech pattern of the current frame to preceding frames, a signal z(n) corresponding to the contribution of preceding excitation of the current frame speech pattern, a current frame correlation parameter signal γ, and a current frame correlation location signal M*. Signal z(n) is formed from its past values responsive to linear prediction parameter signals a k in accordance with ##EQU6## A range of samples M min to M max extending over a plurality of preceding frames is defined. A signal ##EQU7## representing the excitation of the preceding frame is produced from the proceeding frame prescribed format multipulse signal is produced. For each sample M in the range, a signal ##EQU8## is formed corresponding to the contribution of the frame of excitation from m samples earlier. A signal ##EQU9## corresponding to the difference between the current value of the speech pattern y(n) and the sum of the past excitation contribution to the present speech pattern value z(n) and the contribution of the correlated component from sample γy p (n)(M)z(n,M) may be formed. Equation 7 may be expressed as ##EQU10## By setting the derivative of E(γ, M) with respect to γ(M) equal to zero, the value of γ which minimizes E(γ,M) is found to be ##EQU11## and the minimum value of E(γ,M*) is determined by selecting the minimum signal E(M*) from ##EQU12## over the range Mmin<=M<=Mmax. γ can then be formed from equation 9 using the value of M* corresponding to the selected minimum signal E(γ,M) as per Equation 10.
The multiframe correlated component of signal
y.sub.p (n)=γ(M*)z.sub.p (n,M*) (11)
is obtained from signals γ and z p (n,M*).
Signal y p (n) is supplied to frame correlation signal generator 125 which is operative to generate signal ##EQU13## where ##EQU14## responsive to signals y(n) from predictive filter 121, signal y(n) from predictive filter 123 and signal y p (n) from multiframe correlation signal generator 140. Signal C iq is representative of the weighted differences between signals y(n) and the combination of signals y(n) and y p (n). The effect of signal y p (n) in processor 125 is to remove long term redundancy from the weighted differences. The long term redundancy is generally related to the pitch predictable component of the speech pattern. The output of frame correlation generator 125 represents the maximum value of C iq over the current frame and its location q*. Generator 127 produces a pulse of magnitude ##EQU15## and location m i =q*. The signals β i and m i are formed iteratively until I such pulses are generated by feedback of the pulses through excitation signal former 145.
In accordance with the invention, the output of processor 125 has reduced redundancy so that the resulting excitation code obtained from multipulse signal generator 127 has a smaller dynamic range. The smaller dynamic range is illustrated by comparing waveforms 605 and 610 in FIG. 6. Additionally, the removal of the pitch related component from the multipulse excitation code renders the excitation substantially independent of the pitch of the input speech pattern. Consequently, a significant reduction in excitation code bit rate is achieved.
Signal EC comprising the multipulse sequence β i , m i is applied to multiplexor 135 via coder 131. The multipulse signal EC is also supplied to excitation signal former 145 in which an excitation signal v(n) corresponding to signal EC is produced. Signal v(n) modifies the signal formed in predictive filter 123 to adjust the excitation signal EC so that the differences between the weighted speech representative signal from filter 121 and the weighted artificial speech representative signal from filter 123 are reduced.
Multipulse signal generator 127 receives the C iq signals from frame correlation signal generator 127, selected the C iq signal having the maximum absolute vaue and i th element of the coded signal as per Equation 14. The index i is incremented to i+1 and signal y(n) at the output of predictive filter 123 is modified. The process in accordance with Equations 4, 5 and 6 is repeated to form element β i+1 , m i+1 . After the formation of element β I , m I' , the signal having elements β i m 1' β 2 m 2 , . . . , β I m I is transferred to coder 131. As is well known in the art, coder 131 is operative to quantize the β i m i elements and to form a coded signal suitable for transmission to utilization device 148.
Each of filters 121 and 123 in FIG. 1 may comprise a recursive filter of the type described in aforementioned U.S. Pat. No. 4,133,976. Each of generators 125, 127, and 140 as well as excitation signal former 145 may comprise one of the processor arrangements well known in the art adapted to perform the processing required by Equations 4 and 6 such as the C.S.P., Inc. Macro Arithmetic Processor System 100 or other processor arrangements well known in the art. Alternatively, the aforementioned C.S.P. system may be used to accomplish the processing required in all of these generating and forming units. Generator 140 includes a read only memory that permanently stores a set of instructions to perform the functions of Equations 9-11. Processor 125 includes a read-only memory which permanently stores programmed instructions to control the C iq signal formation in accordance with Equation 4. processor 127 includes a read-only memory which permanently stores programmed instructions to select the β i , m i signal elements according to Equation 6 as is well known in the art. These read only memories may be selectively connected to a single processor arrangement of the type described as shown in FIG. 2. The program instructions for the signal processing in the circuit of FIG. 1 is set forth in FORTRAN language form in Appendix A hereto.
FIG. 3 depicts a flow chart showing the operations of signal generators 125, 127, 140, and 145 for each time frame. Referring to FIG. 3, the h k impulse response signals are generated in box 305 responsive to the frame predictive parameters a k in accordance with the transfer function of Equation 1. This occurs after receipt of the FC signal from clock 103 in FIG. 1 as per wait box 303. The generation of the multiframe correlation signal y p (n) and the multiframe correlation parameter signals γ and M* is then performed in multiframe signal generator 140 as per box 306. The operations of box 306 are shown in greater detail in the flow chart of FIG. 4.
Referring to FIGS. 1 and 4, signal z(n) representative of the contribution of preceding excitation is generated (box 401) and stored in multiframe correlation signal generator 140 according to equation 1 responsive to the predictive parameter signals a k . Index M is set to Mmin and minimum error signal E* is set to zero in box 405. The loop including boxes 410, 415, 420, 425, 430, and 435 is then iterated over the range Mmin<=M<=Mmax so that the minimum error signal E(m) and the location of the minimum error signal are determined. In box 410, the contribution of the preceding M samples to the excitation is generated as per Equation 6a and 6b. The error signal for the current frame is generated in box 415 and compared to the minimum error signal E* in decision box 420. If the current error signal is smaller than E*, E* is replaced (box 420), its location M becomes M* (box 425) and decision box 430 is reached. Otherwise, decision box 430 is entered directly from box 420. Sample index M is incremented (box 435) and the loop from box 410 to box 435 is iterated until sample Mmax is detected in box 430. When M=Mmax, correlation parameter γ for the current frame is generated (box 440) in accordance with Equation 9 using sample M* and the multiframe correlation signal y p (n) is generated in box 445. Signals γ, M*, and y p (n) are stored in generator 440. The element index i and the excitation pulse location index q are initially set to 1 in box 307. Upon receipt of signals y(n) and y(n) from predictive filters 121 and 123, signal C iq is formed as per box 309. The location index q is incremented in box 311 and the formation of formation of the next location C iq signal is initiated.
After the C iq signal is formed for excitation signal element i in processor 125, processor 127 is activated. The q index in processor 127 is initially set to 1 in box 315 and the i index as well as the C iq signals formed in processor 125 are transferred to processor 127. Signal C iq * which represents the C iq signal having the maximum absolute value and its location q* are set to zero in box 317. The absolute values of the C iq signals are compared to signal C iq * and the maximum of these absolute values is stored as signal C iq * in the loop including boxes 319, 321, 323, and 325.
After the C iq signal from processor 125 has been processed, box 327 is entered from box 325. The excitation code element location m i is set to q* and the magnitude of the excitation code element β i is generated in accordance with Equation 6. The β i m i element is output to predictive filter 123 as per box 328 and index is incremented as per box 329. Upon formation of the β I m I element of the frame, signal v(n) for the frame is generated as per Equation 6a (box 340) and wait box 303 is reentered. Processors 125 and 127 are then placed in wait states until the FC frame clock pulse of the next frame.
The excitation code in processor 127 is also supplied to code 131. The coder is operative to transform the excitation code from processor 127 into a form suitable for use in network 140. The prediction parameter signals a k for the frame are supplied to an input of multiplexer 135 via delay 133 as signals a' k . The excitation coded signal ECS from coder 131 is applied to the other input of the multiplexer. The multiplexed excitation and predictive parameter codes for the frame are then sent to utilization device 148.
The data processing circuit depicted in FIG. 2 provides an alternative arrangement to excitation signal forming circuit 120 of FIG. 1. The circuit of FIG. 2 yields the excitation code β i , m i for each frame of the speech pattern as well as the redundancy parameter signals for the frame γ, M* in response to the frame prediction residual signal d k and the frame prediction parameter signals a k in The circuit of FIG. 2 may comprise the previously mentioned C.S.P., Inc. Macro Arithmetic Processor System 100 or other processor arrangements well known in the art.
Referring to FIG. 2, processor 210 receives the predictive parameter signals a k and the prediction residual signals d k of each successive frame of the speech pattern from circuit 110 via store 218. The processor is operative to form the excitation code signal elements β 1 m 1 , β 2 , m 2 , . . . , β I , m I , and redundancy parameter signals γ and M* under control of permanently stored instructions in predictive filter processing subroutine read-only memory 201, multiframe correlation processing read-only memory 212, frame correlation signal processing read-only memory 217, and excitation processing read-only memory 205. The permanently stored instructions of these read-only memories are set forth in Appendix A.
Processor 210 comprises common bus 225, data memory 230, central processor 240, arithmetic processor 250, controller interface 220 and input-output interface 260. As is well known in the art, central processor 240 is adapted to control the sequence of operations of the other units of processor 210 responsive to coded instructions from controller 215. Arithmetic processor 250 is adapted to perform the arithmetic processing on coded signals from data memory 230 responsive to control signals from central processor 240. Data memory 230 stores signals as directed by central processor 240 and provides such signals to arithmetic processor 250 and input-output interface 260. Controller interface 220 provides a communication link for the program instructions in the read-only memories 201, 205, 212, and 217 to central processor 240 via controller 215, and input-output interface 260 permits the d k and a k signal to be supplied to data memory 230 and supplies output signals β i , m i , γ and M* from the data memory to coders 131 and 155 in FIG. 1.
The operation of the circuit of FIG. 2 is illustrated in the flow charts of FIGS. 3 and 4. At the start of the speech signal, box 305 in FIG. 3 is entered via box 303 after signal ST is obtained from clock signal generator 103 in FIG. 1. The predictive filter impulse response for signals y(n) and y(n) are formed as per box 305 in processors 240 and 250 under control of instructions from predictive filter processing ROM 201. Box 306 is then entered and the operations of the flow chart of FIG. 4 are carried out responsive to the instructions stored in ROM 212. These operations result in the formation of signals y p (n), γ, and M* and have been described with respect to FIG. 1. Signals γ and M* are made available at the output of input-output interface 260 and signal y p (n) is stored in data memory 230.
Upon completion of the operations of box 306, Controller 215 connects frame correlation signal processing ROM 217 to central processor 240 via controller interface 220 and bus 225 so that the signals C iq , C iq *, and q* are formed as per the operations of boxes 307 through 325 for the current value of excitation signal index i. Excitation signal processing ROM 205 is then connected to computer 210 by controller 215 and the signals β i and m i are generated in boxes 327 through 333 as previously described with respect to FIG. 1. Signal v(n) is then produced for use in the next frame in box 340 as per equation 6a. The excitation signals are generated in serial fashion for i=1, 2, . . . , I in each frame. Upon completion of the operations of FIG. 3 for excitation signal β I , m I , controller 215 places the circuit of FIG. 2 in a wait state as per box 303.
The frame excitation code and the frame redundancy parameter signals from the processor of FIG. 2 are supplied via input-output interface 260 to coders 131 and 155 in FIG. 1 as is well known in the art. Coders 131 and 155 are operative as previously mentioned to quantize and format the excitation code and the redundancy parameter signals for application to utilization device 148. The a k prediction parameter signals of the frame are applied to one input of multiplexer 135 through delay 133 so that the frame excitation code from coder 131 may be appropriately multiplexed therewith.
Utilization device 148 may be a communication system, the message store of a voice storage arrangement, or apparatus adapted to store a complete message or vocabulary of prescribed message units, e.g., words, phonemes, etc., for use in speech synthesizers. Wheatever the message unit, the resulting sequence of frame codes from circuit 120 are forwarded via utilization device 148 to a speech synthesizer such as that shown in FIG. 5. The synthesizer, in turn, utilizes the frame excitation and redundance parameter signal codes from circuit 120 as well as the frame predictive parameter codes to construct a replica of the speech pattern.
Demultiplexer 502 in FIG. 5 separates the excitation code EC, the redundancy parameter codes γ, M*, and the prediction parameters a k of each successive frame. The excitation code, after being decoded into an excitation pulse sequence in decoder 505, is applied to one input of summing circuit 511 in excitation signal former 510. The γ, M* signals produced in decoder 506 are supplied to predictive filter 513 in excitation signal former 510. The predictive filter is operative as is well known in the art to combine the output of summer 511 with signals γ and M* to generate the excitation pulse sequence of the frame. The transfer function of filter 513 is
p(z)=γz.sup.-M* (15)
Signal M* operates to delay the redundancy reduced excitation pulse sequence and signal γ operates to modify the magnitudes of the redundancy reduced excitation pulses so that the frame multipulse excitation signal is reconstituted at the output of excitation signal former 510.
The frame excitation pulse sequence from the output of excitation signal former 510 is applied to the excitation input of speech synthesizer filter 514. The a k predictive parameter signals decoded in decoder 508 are supplied to the parameter inputs of filter 514. Filter 514 is operative in response to the excitation and predictive parameter signals to form a digitally encoded replica of the frame speech signal as is well known in the art. D/A converter 516 is adapted to transform the coded replica into an analog signal which is passed through low-pass filter 518 and transformed into a speech pattern by transducer 520.
The invention has been described with reference to particular illustrative embodiments. It is apparent to those skilled in the art that various modifications may be made without departing from the scope and the spirit of the invention. For example, the embodiments described herein have utilized linear predictive parameters and a predictive residual. the linear predictive parameters may be replaced by formant parameters or other speech parameters well known in the art. ##SPC1## | A multipulse-code approximation of of one frame of a predictive residual signal may lose the frame-to-frame redundancy. Accordingly, pitch redundancy removal during the iterative process of forming the multipulse sequence, rather than frame-to-frame code comparison, provides reduction of excitation signal bit rate, substantially independent of voice pitch. A speech pattern predictive coding arrangement includes forming a prescribed format multipulse excitation signal for each successive time frame of the pattern. The multipulse excitation signal corresponds to the frame predictive residual. The redundancy in the multipulse excitation signal is reduced by forming a signal representative of the similarities between the current frame speech pattern and the speech pattern of preceding frames and removing such similarities from the multipulse excitation signal. Advantageously, the bit rate of the multipulse excitation signal is reduced and the excitation signal is rendered substantially independent of voice pitch. | 6 |
CROSS REFERENCE TO RELATED APPLICATION
[0001] This application claims priority from Japanese Patent Application No. 2010-012058 filed Jan. 22, 2010. The entire content of this priority application is incorporated herein by reference.
TECHNICAL FIELD
[0002] The present invention relates in general to an image-forming device for forming images on recording sheets, and more particularly to an image-forming device having a plurality of photosensitive members arranged in tandem and retained together with corresponding developing devices and developer-accommodating devices at fixed positions in a retaining member that can be withdrawn from a body of the image-forming device along the juxtaposed direction of the photosensitive members.
BACKGROUND
[0003] An image-forming device such as a laser printer for forming color images on recording sheets is well known in the art. One such image-forming device has a plurality of photosensitive members and a plurality of corresponding developer cartridges (each integrally formed of a developing device and a developer-accommodating device) arranged in tandem and held at fixed positions within a retaining member. Parts, consumables, and the like in the photosensitive members and the developer cartridges can be replaced by pulling the retaining member out from a body of the image-forming device along the direction in which the photosensitive members are juxtaposed.
SUMMARY
[0004] In order to keep down running costs in a laser printer or other image-forming device, it is beneficial to be able to separate the developer-accommodating devices (toner cartridges) from the developing devices and the photosensitive members so that the developer-accommodating devices can be replaced individually. However, when developing devices having such individually detachable toner cartridges are employed in an image-forming device configured with a retaining member that is pulled out of the image-forming device in the direction of the juxtaposed photosensitive members, the force applied to the extracted retaining member as a result of operations performed to open and close shutters in the toner cartridge when mounting and removing the toner cartridge can potentially damage the retaining member or cause the image-forming device to overturn.
[0005] It is an object of the present invention to provide an image-forming device having photosensitive members arranged in tandem in a retaining member that can be pulled out of a body of the image-forming device along the juxtaposing direction of this tandem arrangement, whereby one of the developing devices provided in the retaining member has an individually detachable toner cartridge for reducing running costs and the configuration eliminates the risk of damaging the retaining member and overturning the body of the image-forming device due to forces applied to the retaining member when the retaining member is partially withdrawn from the body.
[0006] In order to attain the above and other objects, the invention provides an image forming device. The image forming device includes a casing, a plurality of photosensitive bodies, a plurality of developing devices, a plurality of developer accommodating devices, and a retaining member. The casing is formed with an opening. The plurality of developing devices respectively corresponds to the plurality of photosensitive bodies. The plurality of developer accommodating devices accommodates and supplies developer respectively to the plurality of developing devices. The plurality of developer accommodating devices includes a first developer accommodating device that is individually replaceable and separable from the corresponding developing device and a second developer accommodating device that is replaceable integrally together with the corresponding developing device. The retaining member retains the plurality of photosensitive bodies arranged in an arrangement direction, the plurality of developing devices, and the plurality of developer accommodating devices at fixed positions in the casing. The retaining member is capable of being pulled out from the casing in the arrangement direction through the opening and is movable between a first position where the plurality of photosensitive bodies, the plurality of developing devices, and the plurality of developer accommodating devices are inside the casing and a second position where one of the plurality of developer accommodating devices located at most upstream side in the arrangement direction is replaceable. The one of the plurality of developer accommodating devices located at the most upstream side in the arrangement direction is the first developer accommodating device accommodating black developer. Each of the developer accommodating devices other than the one of the plurality of developer accommodating devices is the second developer accommodating device.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] The particular features and advantages of the invention as well as other objects will become apparent from the following description taken in connection with the accompanying drawings, in which:
[0008] FIG. 1 is a cross-sectional view showing a color multifunction device according to an embodiment of the present invention;
[0009] FIG. 2 is a cross-sectional view illustrating a state in which a retaining case is at a first position where the retaining case is inside a main body of the color multifunction device;
[0010] FIG. 3 is a cross-sectional view illustrating a state in which the retaining case is at a second position where the retaining case is pulled out from the main body;
[0011] FIG. 4 is a cross-sectional view illustrating an operation in which process units are replaced;
[0012] FIG. 5 is a perspective view showing a toner cartridge and a developing device when shutters are at a closed position;
[0013] FIG. 6 is a perspective view showing the toner cartridge and the developing device when the shutters are at an open position;
[0014] FIG. 7( a ) is a explanatory diagram conceptually illustrating a configuration ambient to a rear end of the retaining case in the main body when the process units are replaced; and
[0015] FIG. 7( b ) is an explanatory diagram conceptually illustrating a configuration ambient to a front end of the retaining case in the main body when the process units are replaced.
DETAILED DESCRIPTION
[0016] Next, an embodiment of the present invention will be described while referring to the accompanying drawings. The following description first covers the overall structure of a color multifunction device of the embodiment according to the present invention and subsequently includes a detailed description of a process unit having a developer-accommodating device accommodating black developer.
[0017] As shown in FIG. 1 , a color multifunction device 1 has a main body 10 and a flatbed scanner. 20 disposed above the main body 10 . Within the main body 10 , the color multifunction device 1 primarily includes a sheet-feeding unit 30 for supplying sheets of a paper P, an image-forming unit 40 for forming images on sheets of paper P supplied by the sheet-feeding unit 30 , and a sheet-discharging unit 90 for discharging the sheets of paper P after images have been formed thereon.
[0018] In the following description, directions related to the color multifunction device 1 will refer to directions seen from the perspective of an operator when operating the color multifunction device 1 . Specifically, the right side of the color multifunction device 1 in FIG. 1 will be referred to as the “front” or the “near side”; the left side as the “rear” or the “far side”; the near side in FIG. 1 as “left”; and the far side in FIG. 1 as “right.” Also, the upper and lower sides along the vertical in FIG. 1 will be referred to as “upper” and “lower” in the description.
[0019] The flatbed scanner 20 disposed above the main body 10 is a document-reading device well known in the art. During a copy operation and the like, the flatbed scanner 20 generates image data by irradiating light onto an original document placed in the flatbed scanner 20 and reads the image from the original document.
[0020] The sheet-feeding unit 30 is disposed in a bottom section of the main body 10 and includes a paper tray 31 for accommodating sheets of paper P, and a paper-feeding mechanism 32 for conveying sheets of paper P from the paper tray 31 to the image-forming unit 40 . The paper-feeding mechanism 32 separates and conveys the paper P accommodated in the paper tray 31 to the image-forming unit 40 one sheet at a time.
[0021] The image-forming unit 40 primarily includes an exposure unit 50 , four process units including a process unit 61 and three process units 62 , a transfer unit 70 , and a fixing unit 80 .
[0022] The exposure unit 50 is provided in a top section of the main body 10 and includes a laser light source, a polygon mirror, lenses, reflecting mirrors, and the like (not shown in the drawings). Laser beams emitted from the laser light source are reflected off the polygon mirror and the reflecting mirrors, pass through the lenses, and are scanned at a high speed over surfaces of photosensitive drums described later.
[0023] The process unit 61 and the process units 62 are disposed between the sheet-feeding unit 30 and the exposure unit 50 and are juxtaposed (arranged in tandem) in the front-to-rear direction. The process units 61 and 62 are held in a retaining case 65 .
[0024] The retaining case 65 has a bottomless frame-like structure, for example, and is capable of moving between a first position where the retaining case 65 is mounted in the main body 10 (see FIG. 2 ) and a second position where the retaining case 65 is removed forwardly from the main body 10 , i.e., the process unit 61 is within the main body 10 and the process units 62 are outside the main body 10 while the retaining case 65 retains the process units 61 and 62 (see FIG. 3 ). Guide rails 10 R (see FIG. 3 ) are formed on inner sides of the main body 10 for guiding the retaining case 65 in the front-to-rear direction. A front cover 11 is provided on a front side of the main body 10 over an opening 11 a formed in the main body 10 and can be pivotally rotated downward to expose the opening 11 a or upward to cover the opening 11 a. A handle 65 H is provided on a front end of the retaining case 65 . By opening the front cover 11 and pulling on the handle 65 H, an operator can pull the retaining case 65 out of the main body 10 in a pull-out direction through the opening 11 a, i.e., moves the retaining case 65 to the second position, as illustrated in FIG. 3 . Once the retaining case 65 has been positioned at the second position, the operator can replace components of the process units 61 and 62 that, during their normal operating state, are positioned far side (rearward) of the main body 10 . That is, the second position indicates the position of the retaining case 65 at which the developer-accommodating device (a toner cartridge 100 ) of the process unit 61 disposed farthest inward in the retaining case 65 among the four process units 61 and 62 with respect to the pull-out direction can be accessed and replaced.
[0025] The structure for enabling the operation to pull the retaining case 65 outward with respect to the main body 10 and to support the retaining case 65 while maintaining the retaining case 65 in either the first position or the second position will be described later in greater detail.
[0026] As shown in FIG. 1 , the process unit 61 disposed on a farthest side of the retaining case 65 among the four process units 61 and 62 includes a photosensitive drum 61 A, a charger 61 B, the toner cartridge 100 accommodating black toner, and a developing device 200 . The developing device 200 includes a developing roller 61 C, a supply roller 61 D, and a thickness-regulating blade 61 E. The structure of the process unit 61 will be described later in greater detail.
[0027] The photosensitive drum 61 A and the charger 61 B of the process unit 61 may be configured so that they are mounted in and removed from the retaining case 65 together (i.e., replaceable as a unit) or may be fixed to the retaining case 65 to form a single unit therewith. Alternatively, the developing roller 61 C, the supply roller 61 D, and the thickness-regulating blade 61 E constituting the developing device 200 may be configured as an integrated unit that is mounted in and removed from the retaining case 65 , or may be fixed to the retaining case 65 together with the photosensitive drum 61 A and the charger 61 B and formed as a single unit with the retaining case 65 . If the developing device 200 is detachably mounted in the retaining case 65 , the photosensitive drum 61 A and the charger 61 B may be configured to be detachably mounted as a unit or to be mounted and removed separately.
[0028] Each of the three process units 62 among the four process units disposed nearer frontward in the retaining case 65 includes a photosensitive drum 62 A, a charger 62 B, a developing roller 62 C, a supply roller 62 D, a thickness-regulating blade 62 E, and a developer-accommodating device 62 G. The developer-accommodating devices 62 G of these process units 62 accommodate toner in one of the colors cyan, magenta, and yellow, respectively. A developing device 62 H of each process unit 62 is configured of the developing roller 62 C, the supply roller 62 D, and the thickness-regulating blade 62 E and is integrally configured with the developer-accommodating device 62 G and detachably mounted in the retaining case 65 (see FIG. 4 ).
[0029] As with the photosensitive drum 61 A and the charger 61 B of the process unit 61 , the photosensitive drum 62 A and the charger 62 B of the process unit 62 may be configured to be detachably mounted in the retaining case 65 (i.e., replaceable) or fixed to the retaining case 65 to form a single unit therewith. The process unit 62 (i.e., the photosensitive drum 62 A, the charger 62 B, the developing roller 62 C, the supply roller 62 D, the thickness-regulating blade 62 E, and the developer-accommodating device 62 G) may be detachably mounted in the retaining case 65 as a unit.
[0030] The transfer unit 70 is disposed between the sheet-feeding unit 30 and the process units 61 and 62 . The transfer unit 70 primarily includes a drive roller 71 , a follow roller 72 , an endless conveying belt 73 stretched taut about the rollers 71 and 72 , and four transfer rollers 74 . The outer surface of the conveying belt 73 is in contact with each of the photosensitive drums 61 A and 62 A and is pinched between the transfer rollers 74 disposed on the inner side of the conveying belt 73 and the photosensitive drums 61 A and 62 A.
[0031] A cleaning unit 75 is disposed beneath the conveying belt 73 . The cleaning unit 75 contacts the conveying belt 73 for removing toner, paper dust, and other deposited matter from the conveying belt 73 and for recovering this deposited matter.
[0032] The fixing unit 80 is disposed rearward of the process units 61 and 62 and the transfer unit 70 . The fixing unit 80 primarily includes a heating roller 81 , and a pressure roller 82 disposed in confrontation with the heating roller 81 and applying pressure to the same.
[0033] In the image-forming unit 40 , the chargers 61 B and 62 B apply a uniform charge to the respective surfaces of the photosensitive drums 61 A and 62 A, after which the surfaces are exposed to laser beams emitted from the. exposure unit 50 in a high-speed scan to form electrostatic latent images on the charged surfaces of the photosensitive drums 61 A and 62 A based on image data. Toner accommodated in the toner cartridge 100 and the developer-accommodating devices 62 G is supplied respectively to the developing rollers 61 C and 62 C via the supply rollers 61 D and 62 D. As the developing rollers 61 C and 62 C rotate, toner carried on the surfaces of the same is regulated to a prescribed thickness by the respective thickness-regulating blades 61 E and 62 E.
[0034] The toner layers of uniform thickness carried on the developing rollers 61 C and 62 C are supplied to the electrostatic latent images formed on the photosensitive drums 61 A and 62 A, respectively, whereby the electrostatic latent images are developed into visible toner images on the photosensitive drums 61 A and 62 A. Subsequently, as a sheet of paper P carried on the conveying belt 73 is sequentially conveyed between the photosensitive drums 61 A and 62 A and the conveying belt 73 (the transfer rollers 74 ), the toner images carried on the photosensitive drums 61 A and 62 A are sequentially transferred onto and superposed on the sheet of paper P. When the sheet of paper P is then conveyed between the heating roller 81 and the pressure roller 82 , the toner images transferred on the sheet are fixed to the sheet by heat.
[0035] The sheet-discharging unit 90 primarily includes a paper-discharge path 91 for guiding sheets of paper P upward in the main body 10 from the exit side of the fixing unit 80 while inverting the sheets, and a discharge roller 92 for discharging the inverted sheets onto a discharge tray 15 formed on top of the main body 10 . Thus, after the toner images are fixed to the sheet of paper P by heat in the fixing unit 80 , the sheet is conveyed from the fixing unit 80 into the paper-discharge path 91 , and the discharge roller 92 discharges the sheet onto the discharge tray 15 .
[0036] Next, the structure of the process unit 61 (the toner cartridge 100 and the developing device 200 ) will be described in detail and contrasted with the process units 62 while referring primarily to FIGS. 5 and 6 . FIGS. 5 and 6 show a bottom view of the toner cartridge 100 and a top view of the developing device 200 .
[0037] As shown in FIGS. 3 and 4 , the toner cartridge 100 of the process unit 61 is detachably mounted on the developing device 200 . When mounted on the developing device 200 , the toner cartridge 100 is positioned above and adjacent to the developing device 200 .
[0038] As shown in FIGS. 5 and 6 , the toner cartridge 100 is a substantially cylindrical container with side walls 110 closing both left and right ends thereof. The cylindrically shaped wall of the toner cartridge 100 is formed with a first supply opening 111 for supplying toner from the toner cartridge 100 to the developing device 200 .
[0039] A cylindrical first shutter 120 is provided on the toner cartridge 100 around the cylindrical wall of the toner cartridge 100 . By rotating the first shutter 120 in a circumferential direction relative to the toner cartridge 100 , the shutter 120 can open and close the first supply opening 111 . Specifically, a first shutter supply opening 121 is formed in the first shutter 120 at a position that perfectly overlaps the first supply opening 111 formed in the toner cartridge 100 when the first shutter 120 is in an open position illustrated in FIG. 6 . When the first shutter 120 is rotated a prescribed stroke in the circumferential direction relative to the toner cartridge 100 to a closed position illustrated in FIG. 5 , the first shutter 120 completely blocks the first supply opening 111 .
[0040] A ridge part 110 P is provided on each of the left and right side walls 110 of the toner cartridge 100 . The ridge parts 110 P extend radially from the center of the side walls 110 to the outer edge thereof and have a rectangular cross section. Protruding parts 120 P having the same cross-sectional shape as the ridge parts 110 P are provided on longitudinal ends of the first shutter 120 .
[0041] When the first shutter 120 is set in the closed position as shown in FIG. 5 , the protruding parts 120 P are aligned with the outer ends of the corresponding ridge parts 110 P, forming continuous guide rails for guiding the toner cartridge 100 when the toner cartridge 100 is mounted on the developing device 200 described later. When the first shutter 120 is rotated to the open position while the toner cartridge 100 is attached to the developing device 200 , the protruding parts 120 P move circumferentially within second groove parts R 2 (described later in greater detail) formed in side walls of the developing device 200 so that the toner cartridge 100 is engaged (interlocked) with the developing device 200 (see FIG. 6 ).
[0042] A handle 120 H is provided on the peripheral surface of the first shutter 120 . The handle 120 H extends horizontally rearward from an upper portion of the first shutter 120 when the toner cartridge 100 is mounted on the developing device 200 (i.e., when the first shutter 120 is in the open position), as shown in FIG. 1 . When the operator grips the handle 120 H and rotates the handle 120 H from this horizontal position upward relative to the mounted toner cartridge 100 , the first shutter 120 is rotated to the closed position, disengaging (unlocking) the toner cartridge 100 from the developing device 200 so that the toner cartridge 100 can be removed (see FIG. 3 ).
[0043] Further, an agitator 140 well known in the art is provided inside the toner cartridge 100 (see FIG. 1 ). The agitator 140 is primarily configured of a rotational shaft rotatably supported in the left and right side walls 110 , and a plurality of sheet-like agitating blades. The agitating blades are formed of a flexible material and are fixed to the rotational shaft.
[0044] A motor (not shown) provided in the main body 10 applies a drive force to the rotational shaft for rotating the agitator 140 in the toner cartridge 100 . When the rotational shaft rotates, the distal edges of the agitating blades slanted relative to the rotational shaft scrape against the inner surface of the toner cartridge 100 , agitating toner in the toner cartridge 100 and conveying this toner toward the first supply opening 111 .
[0045] As shown in FIG. 1 , the developing device 200 is provided with the developing roller 61 C, the supply roller 61 D, the thickness-regulating blade 61 E, and the like. The structure and arrangement of the developing device 200 is similar to the developing device 62 H of the process units 62 , except that the toner cartridge 100 is detachably mounted on the developing device 200 as the developer-accommodating device, and an accommodating recessed part 210 S (see FIG. 6 ) for receiving the mounted toner cartridge 100 is formed in the developing device 200 at a position opposing the supply roller 61 D.
[0046] As shown in FIGS. 5 and 6 , a second supplying opening 211 is formed in a curved wall of the developing device 200 forming the arch shape (arc-shaped in a cross section) of the accommodating recessed part 210 S at a position corresponding to the first supply opening 111 formed in the toner cartridge 100 . The second supplying opening 211 functions to supply toner from the toner cartridge 100 to the developing device 200 .
[0047] A second shutter 220 is also provided in the developing device 200 around the arch-shaped wall of the accommodating recessed part 210 S. By rotating in a circumferential direction relative to the accommodating recessed part 210 S, the second shutter 220 can open and close the second supplying opening 211 formed in the accommodating recessed part 210 S. More specifically, a second shutter supply opening 221 is formed in the second shutter 220 at a position that is perfectly aligned with the second supplying opening 211 formed in the developing device 200 when the second shutter 220 is in an open position (see FIG. 6 ). By rotating the second shutter 220 a prescribed stroke in the circumferential direction relative to the developing device 200 to a closed position, the second shutter 220 completely blocks the second supplying opening 211 (see FIG. 5 ).
[0048] A grooved part 210 R is formed on the inside surface of each of the left and right walls of the accommodating recessed part 210 S. The grooved part 210 R includes a first groove part R 1 extending radially downward from the center of curvature of the accommodating recessed part 210 S, a second groove part R 2 following circumferential directions (both forward and rearward) from the bottom end of the first groove part R 1 , and a funnel-shaped part R 3 formed at the top of the first groove part R 1 in a funnel shape that widens toward the top in order to facilitate insertion of the ridge part 110 P and the protruding part 120 P when mounting the toner cartridge 100 in the accommodating recessed part 210 S.
[0049] An inner circumferential protruding part 220 P is formed on each of the left and right ends of the second shutter 220 for slidably engaging in the second groove parts R 2 . A notched part 220 Q is formed in the inner circumferential protruding part 220 P in a portion opposing the bottom end of the first groove part. R 1 when the second shutter 220 is at the closed position so that the protruding part 120 P can be inserted into the notched part 220 Q when mounting the toner cartridge 100 (see FIG. 5 ).
[0050] While chemical toner is used for the color toner accommodated in the developer-accommodating devices 62 G of the process units 62 in the embodiment, pulverized toner is used for the black toner accommodated in the toner cartridge 100 of the process unit 61 .
[0051] Here, “chemical toner” denotes toner that is manufactured according to chemical processes, in contrast to the traditional toners that are manufactured through a mechanical pulverizing process. Chemical toner can be produced through a variety of methods, including emulsion polymerization and aggregation, suspension polymerization, emulsion aggregation, and dissolution suspension. “Pulverized toner” includes not only traditional toner manufactured according to a mechanical pulverizing process, but also to the same toner that has been chemically treated to produce rounder toner particles.
[0052] By employing pulverized toner, which has lower fluidity than chemical toner, it is possible to reduce the likelihood of toner leaking from the developing device 200 and to extend the service life of the developing device 200 in terms of the number of printed sheets, since the service life is greatly dependent on the lifespan of the toner leakage preventing seal.
[0053] Next, the structure for enabling the retaining case 65 to be pulled outward from the main body 10 and for supporting the retaining case 65 in fixed positions will be described with reference to FIGS. 2 through 4 and FIGS. 7( a ) and 7 ( b ). FIGS. 7( a ) and 7 ( b ) are explanatory diagrams conceptually illustrating a rear supporting structure SR and a front supporting structure SF when the retaining case 65 is at the second position shown in FIG. 4 .
[0054] A flange part 65 R is provided on each of the left and right walls of the retaining case 65 . The flange parts 65 R extend along the walls in the front-to-rear direction and are formed by bending the upper edges of the side walls outward. As shown in FIG. 7( a ), rollers 65 K are provided on the rear end of the retaining case 65 rearward of the flange parts 65 R.
[0055] Guide rails 10 R are provided in the main body 10 on left and right sides of the space provided for accommodating the retaining case 65 . The guide rails 10 R serve to guide the retaining case 65 in the pull-out direction while maintaining the retaining case 65 in a horizontal orientation. As shown in FIG. 7( b ), a sloped part 10 S and a roller 10 K are provided on the front end of each guide rail 10 R, and a roller 10 J is disposed slightly rearward and above the sloped part 10 S and the roller 10 K on each side.
[0056] As shown in FIGS. 3 , 4 , and 7 ( a ), a restricting frame 10 F is provided in the main body 10 on each of the left and right sides of the space accommodating the retaining case 65 . The restricting frames 10 F run parallel to the guide rails 10 R and restrict the retaining case 65 from moving the flange parts 65 R upward at least for the region of the rear supporting structure SR when the retaining case 65 is in the second position.
[0057] As shown in FIGS. 2 and 3 , a sloped part 10 N and a positioning part 10 M are provided on the rear end of each of the guide rails 10 R.
[0058] When the retaining case 65 is in the first position shown in FIG. 2 , the rollers 65 K on the rear end of the retaining case 65 are accommodated in the positioning parts 10 M provided on the main body 10 and are fixed in position by the same. At this time, the flange parts 65 R of the retaining case 65 rest on the guide rails 10 R of the main body 10 and are stably supported in a fixed position by the same. Operations of the color multifunction device 1 can be performed when the retaining case 65 is in this position.
[0059] When the retaining case 65 is pulled outward from this position, the rollers 65 K provided on the rear end of the retaining case 65 roll up the sloped parts 10 N onto the guide rails 10 R, while the flange parts 65 R at the front end of the retaining case 65 slide up the sloped parts 10 S and pass over the rolling rollers 10 K, thereby guiding the retaining case 65 forward.
[0060] When the retaining case 65 arrives at the second position shown in FIG. 3 , leaf springs 65 S mounted on the flange parts 65 R contact the rollers 10 J on the main body 10 , and this contact halts movement of the retaining case 65 in the pull-out direction. In this position, the operator can replace the toner cartridge 100 of the process unit 61 and the developer-accommodating devices 62 G (and the developing rollers 62 C, the supply rollers 62 D, and the thickness-regulating blades 62 E) of the process units 62 .
[0061] As shown in FIGS. 3 and 4 , the process unit 61 is still positioned within the main body 10 when the retaining case 65 is in the second position. At the same time, the process unit 61 is positioned between the front supporting structure SF and the rear supporting structure SR, and the retaining case 65 is supported in the main body 10 at the front supporting structure SF and the rear supporting structure SR.
[0062] Specifically, since the rollers 65 K are resting on the guide rails 10 R, as shown in FIG. 7( a ), downward movement of the retaining case 65 is restricted. Further, the restricting frames 10 F disposed above the rollers 65 K and the flange parts 65 R restrict upward movement of the retaining case 65 .
[0063] As shown in FIG. 7( b ), downward movement of the retaining case 65 is restricted since the flange parts 65 R rest on the rollers 10 K, and upward movement is restricted since the rollers 10 J are positioned above the flange parts 65 R.
[0064] The leaf springs 65 S serving to fix the retaining case 65 in the second position have center regions that bulge gently upward. The front ends of the leaf springs 65 S are embedded in the corresponding flange parts 65 R while the rear ends can slide into recessed parts formed in the top surfaces of the corresponding flange parts 65 R. Hence, if the user exerts greater force to pull the retaining case 65 farther forward from the state shown in FIG. 7( b ), the leaf springs 65 S are configured to elastically deform and pass beneath the rollers 10 J as the retaining case 65 moves forward.
[0065] When the user pulls the retaining case 65 past the second position, the rollers 65 K on the rear end of the retaining case 65 pass over the corresponding sloped parts 10 S and the rollers 10 K, allowing the retaining case 65 to be completed removed from the main body 10 . Thus, the operator can repair or replace the photosensitive drums 61 A and 62 A, the chargers 61 B and 62 B, and the like after removing the retaining case 65 in this way.
[0066] Next, operations for replacing the toner cartridge 100 in the process unit 61 having the above construction will be described.
[0067] When the process unit 61 is positioned as shown in FIGS. 1 and 2 , the toner cartridge 100 is engaged with the developing device 200 , and the first shutter 120 and the second shutter 220 are at the open position. In other words, as shown in FIG. 6 , the protruding part 120 P of the first shutter 120 is at a position offset from the ridge part 110 P and is inset in the second groove part R 2 . Thus, the mounted toner cartridge 100 is firmly and inseparably fixed to the developing device 200 .
[0068] When the toner cartridge 100 is out of black toner or needs to be replaced for any reason, the operator first opens the upper cover 12 , grips the handle 120 H, and then pulls the retaining case 65 forward until the retaining case 65 becomes fixed in the second position. When the handle 120 H is rotated rearward (counterclockwise direction in FIG. 1 ), the first and second shutters 120 and 220 on the toner cartridge 100 and the developing device 200 are closed and the toner cartridge 100 is disengaged from the developing device 200 (see FIG. 3 ). Next, the operator extracts the toner cartridge 100 upward through the opening 11 a.
[0069] More specifically, the operation to rotate the handle 120 H rearward shifts the first shutter 120 and the second shutter 220 from the position shown in FIG. 6 to the position shown in FIG. 5 , causing the first shutter 120 and the second shutter 220 to shift to the closed position and the protruding parts 120 P of the first shutter 120 to arrive at a position aligned with the ridge parts 110 P. Consequently, the protruding parts 120 P can pass through the respective first groove parts R 1 which are the portion of the grooved parts 210 R that extend radially, thereby enabling the operator to pull the toner cartridge 100 upward, as illustrated in FIG. 4 .
[0070] To mount a new toner cartridge 100 in the process unit 61 , the operator first opens the front cover 11 , then pulls the retaining case 65 forward until the retaining case 65 becomes fixed in the second position shown in FIG. 3 . Subsequently, the operator mounts the new toner cartridge 100 .
[0071] During this operation, the operator aligns the ridge parts 110 P and the protruding parts 120 P on left and right sides of the toner cartridge 100 in the state shown in FIG. 5 with the grooved parts 210 R on the left and right sides of the developing device 200 and inserts the ridge parts 110 P and the protruding parts 120 P in the corresponding grooved parts 210 R until the entire toner cartridge 100 is seated in the accommodating recessed part 210 S of the developing device 200 . Subsequently, the operator rotates the handle 120 H forward (clockwise direction in FIG. 1 ), moving the first shutter 120 and the second shutter 220 to their open positions shown in FIG. 6 .
[0072] Through this operation, the protruding parts 120 P of the first shutter 120 enter the respective second groove parts R 2 of the grooved parts 210 R and move to a position offset from the respective ridge parts 110 P. Accordingly, the mounted toner cartridge 100 is firmly fixed to and inseparable from the developing device 200 .
[0073] Since the second shutter 220 of the developing device 200 opens and closes the second supplying opening 211 in association with the handle 120 H opening and closing the first shutter 120 , both the first shutter 120 and the second shutter 220 are easily opened and closed through a single operation. Further, the toner cartridge 100 is disengaged from the developing device 200 in association with the operation of the handle 120 H to switch these shutters 120 and 220 to their closed positions and is engaged with the developing device 200 in association with the operation of the handle 120 H to switch the shutters 120 and 220 to their open positions, thereby achieving both safety and simplicity of operations.
[0074] When one of the developer-accommodating devices 62 G of the process units 62 must be replaced together with the developing device 62 H (i.e., the developing roller 62 C, the supply roller 62 D, and the thickness-regulating blade 62 E) because the developer-accommodating device 62 G has run out of cyan, magenta, or yellow toner, for example, the operator opens the front cover 11 , grips the handle 65 H, and pulls the retaining case 65 forward to the second position and replaces the relevant components, as illustrated in FIG. 4 .
[0075] Here, the retaining case 65 may be completely separately removed from the main body 10 before replacing the components of the process units 61 and 62 .
[0076] As shown in FIG. 4 , guide grooves 65 G are formed in the inner surfaces of both side walls constituting the retaining case 65 . The guide grooves 65 G function to guide the vertical sliding movement of the developer-accommodating devices 62 G and the developing devices 62 H when they are mounted in the retaining case 65 and to maintain the mounted developing devices 62 H (particularly the developing rollers 62 C) at a fixed position in the bottom ends of the guide grooves 65 G. This construction for mounting and removing the developer-accommodating devices 62 G and the developing device 62 H facilitates the smooth replacement of components in the process units 62 .
[0077] The color multifunction device 1 according to the embodiment having the construction described above primarily produces the following advantages and effects.
[0078] As described above, the color multifunction device 1 has the drawer-like retaining case 65 for accommodating the plurality of developer-accommodating devices in tandem. Of these developer-accommodating devices, the toner cartridge 100 that accommodates black developer is detachably mounted in the process unit 61 disposed in the farthest position of the retaining case 65 relative to the pull-out direction. Since this position affords the most stable operations when the retaining case 65 is fixed in the second position, replacement of the toner cartridge 100 accommodating black developer is both easy and safe, and running costs can be reduced.
[0079] Further, the process units 62 whose developing devices 62 H and corresponding developer-accommodating devices 62 G accommodating color toners can be integrally separated from the retaining case 65 as a unit are arranged toward the near side of the retaining case 65 relative to the pull-out direction. This structure of the process units 62 eliminates the opening and closing of shutters in the developer-accommodating devices 62 G, thereby making replacement of the process units 62 easy and safe.
[0080] Among the developer accommodating devices 62 G and the toner cartridge 100 , the toner cartridge 100 can be replaced separately from the process unit 61 . Since the toner cartridge 100 accommodates black toner, which is generally consumed faster than the color toners, this configuration can greatly reduce running costs.
[0081] The process unit 61 in which the toner cartridge 100 is detachably mounted is positioned inside the main body 10 when the retaining case 65 is pulled out to the second position. This arrangement greatly reduces the risk that forces applied to the retaining case 65 during operations to open and close shutters 120 and 220 when mounting and removing the toner cartridge 100 will cause damage to the retaining case 65 or overturn the main body 10 of the color multifunction device 1 .
[0082] Further, when the retaining case 65 is pulled out and fixed in the second position, the process unit 61 in the retaining case 65 is supported in the main body 10 at two locations, i.e., the front side (the front supporting structure SF) and the rear side (the rear supporting structure SR). Therefore, operations for opening and closing the shutters 120 and 220 when mounting and removing the toner cartridge 100 can be performed more easily and safely.
[0083] While the invention has been described in detail with reference to the embodiment thereof, it would be apparent to those skilled in the art that many modifications and variations may be made therein without departing from the spirit of the invention, the scope of which is defined by the attached claims.
[0084] While the recording sheets described in the embodiment are paper P, such as normal paper or postcards, the recording sheets may also be transparencies or the like.
[0085] The specific structure and arrangement of other components constituting the image-forming device, such as the exposure device, retaining member, photosensitive drums, developer-accommodating devices, and operating member (handle), may be modified as desired and are not limited to the description in the above-mentioned embodiment.
[0086] Further, while the image-forming device with process units according to the present invention is the color multifunction device 1 in the embodiment, the image-forming device may also be a photocopier, printer, or the like. Also, the image-forming device of the embodiment includes four process units 61 and 62 , but the present invention may be applied to any image-forming device having a plurality of developer-accommodating devices, including one that accommodates black developer. | An image forming device includes a casing, photosensitive bodies, developing devices, developer accommodating devices, and a retaining member. The developer accommodating devices includes a first developer accommodating device that is individually replaceable and separable from the corresponding developing device and a second developer accommodating device that is replaceable together with the corresponding developing device. The retaining member retains the photosensitive bodies arranged in an arrangement direction, the developing devices, and the developer accommodating devices at fixed positions within the casing. The retaining member is capable of being pulled out from the casing and is movable between a housed position and a withdrawn position. One of the developer accommodating devices located at a most upstream side in the arrangement direction is the first developer accommodating device, and each of the developer accommodating devices other than the one of the developer accommodating devices is the second developer accommodating device. | 6 |
BACKGROUND OF THE INVENTION
This invention relates to methods and devices used to measure the liquid levels in a cryogenic environment. More specifically, the invention relates to a new and improved method and apparatus for assembling a liquid helium level sensor that is used for measuring the liquid helium level in a cryogenic cooler.
Commonly used liquid helium sensors employ a string of superconducting NbTi filament in either rigid or flexible tubing. Generally, filament sizes range from 0.0005 inch to 0.002 inch in diameter. The sensor operates by measuring the resistance of the portion of the superconductor filament that is above the liquid helium level. The portion that is submerged in the liquid will not contribute measurable resistance because it is in the superconducting state at the temperature of liquid helium. Very thin NbTi filament is employed so that the resistance generated by that portion of the filament above the liquid helium surface produces a measurable voltage drop across the entire filament even with a current as small as 50 mA to 100 mA. The liquid helium level is then inversely proportional to the voltage drop measured, given a constant excitation current.
In general, the sensitivity and accuracy of the sensor increases as the resistance of the superconducting filament increases. Normally, there are two ways to increase the resistivity of the filament. The first way is to reduce the diameter of the filament. The second method involves etching off the copper matrix from the NbTi—Cu filament, because copper has very low resistivity.
In practice, very thin filament is difficult to handle, easy to break and is so thin that is extremely difficult to manufacture. Also, very thin filament size reduces the current carrying capacity of the superconducting filament, thus reducing the voltage output. This causes a reduction of the signal to noise ratio and reduces the accuracy of the measuring device.
BRIEF SUMMARY OF THE INVENTION
The present invention provides a novel technique for assembling superconducting filaments and heaters to form a single object for use as a cryogenic fluid indicator in a cryogenic environment. The present invention provides a high degree of sensitivity and reliability in comparison to previous methods.
The present invention provides a thicker NbTi filament that is connected in series to increase the output voltage. Increasing the output voltage increases the sensitivity to changes in the level of liquid helium and improves the accuracy for measuring the voltage drop. The present invention can also be modified from a single filament level sensor to a multiple filament level sensor by a relatively simple change in the connection scheme.
The present invention provides better sensitivity to the liquid helium level due to the longer resistive filament. The present invention also achieves better accuracy because of the higher resistance of the filament used in the present invention. The present invention is also more reliable than previous methods because larger diameter filament can be used. Lastly, manufacturing a very thin filament presents a high probability of breakage during the manufacturing process. Therefore, using a thicker filament reduces this risk and the cost associated with the manufacturing process.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic showing a liquid helium level sensor installed in a liquid helium reservoir.
FIG. 2 is a block diagram of the circuitry of a liquid helium level sensor.
FIG. 3 is a schematic showing the liquid helium level sensor of the present invention.
FIG. 4 is another schematic showing another embodiment of the present invention.
DETAILED DESCRIPTION
Reference is now made to the drawings wherein like numbers represent like elements throughout. FIG. 1 is a schematic of the liquid helium level sensor of the present invention showing the cryostat 1 , the cryogenic fluid 2 , the liquid-gas interface 3 , the filament 40 and the superconductive solder 10 . Also shown in FIG. 1 is an electric current source 52 , current switches 53 and positive and negative voltage terminals 61 , 62 .
FIG. 2 is a schematic block diagram of a voltage measurement device 51 , a rate sensor 54 , a current source 52 , and a current switch 53 . As shown, the current source 52 is connected to the filament 40 and heater 20 through the current switch 53 . A voltmeter 61 is then connected to measure the voltage drop across the length of the filament 40 . The voltmeter measures the voltage drop at voltage terminals 61 , 62 .
In normal operation of this general embodiment of this invention, the filament 40 and heaters 20 are placed within a rigid or flexible tube 30 and lowered into the cryostat 1 until at least a portion of the filament 40 is submerged. As discussed above, the extremely low temperature of the liquid phase of the helium 2 makes the filament 40 a superconductor.
Current from the current source 52 is then applied through the switch 53 to the heater 20 and filament 40 . Normally, between 50 and 200 mAmps are used. Initially, there will be no voltage drop generated through the filament 40 because it is all superconducting. However, as the heater 20 heats the filament 40 , it will produce a region of normal resistance in the filament 40 , and thus a measurable voltage drop across voltage terminals 61 , 62 . In general, it takes between 0.1-1 second to warm that portion of the filament 40 situated above the liquid helium 2 to the point that it provides some measurable electrical resistance. The heat from the heater 20 will progress down the filament 40 to the gas-liquid interface 3 , at which point it ceases to have an effect on the filament 40 . Thus, that portion of the filament 40 situated above the gas-liquid interface 3 will offer normal electrical resistance while that below the gas-liquid interface 3 will be superconductive. In general, the resistance offered by the filament 40 above the superconducting portion will produce a voltage drop of up to approximately 50 volts.
The voltage drop across the filament 40 increases in a generally linear manner, the rate of change being dV/dt. As the gas-liquid interface 3 is approached, the voltage becomes constant, or the rate of increase of voltage changes until dV/dt=0 as the normal resistive state of the filament 40 has reached the gas-liquid interface 3 .
At a low value of dV/dt, the rate sensor 54 causes the switch 53 to open. Current then stops flowing through the filament 40 and the heater 20 . Therefore, current only flows during the time necessary to warm the filament 40 above the gas-liquid interface 3 . This minimizes the evaporation of liquid helium 2 due to heat added while measuring the level of the liquid helium 2 . The current could also be cycled to reduce liquid helium 2 evaporation.
The present invention uses a combination of superconducting filament 40 and heater 20 to improve accuracy and sensitivity in liquid helium 2 level measurement. The present invention also employs a thicker NbTi filament 40 connected in series to increase the output voltage. The NbTi filament 40 used will range between 0.001 in. and 0.005 in. Use of a thicker filament increases the sensitivity to changes in helium level and increases the accuracy of measurement. This new and unique invention provides for higher sensitivity to changes in the liquid helium 2 level because the present invention provides for a longer resistive region. Further, the amount of voltage drop increases linearly with the amount of resistance. Therefore, the greater the voltage drop, the more easily it is measured, and thus, the more accurately it is measured. Additionally, the filament 40 used in the present invention can be thicker than what is presently used. The filament 40 used in the present invention is more reliable and less subject to breakage. Thicker filaments 40 are far easier to manufacture than filaments 40 that are presently being used. The filament 40 employed is common commercial NbTi filament of approximately 46% to 48% titanium by weight.
The present invention also provides for the ability to use a multifold superconducting filament 40 in the level sensor in contrast to a conventional, single filament 40 . Multifold configurations generally consist of filament 40 connected using a superconductive solder 10 . A multifold configuration, as further provided for in this disclosure will increase the sensor accuracy by a factor of two, as illustrated in FIG. 3 , or by a factor of four, as shown in FIG. 4 . Obviously, the concept can be extended to as many folds as are required to further enhance accuracy.
FIG. 3 shows a two length filament 140 wherein the filament 140 is comprised of a first length 141 having a first end 241 connected to the voltage terminal 161 and a second end 242 and a second length 142 having first end 243 connected to the second end 242 of the first length 141 and a second end 244 connected to a voltage terminal 162 . FIG. 4 illustrates an example of the use of four lengths 341 , 342 , 343 , 344 of superconducting filament 340 wherein the superconducting filament 340 is comprised of a first length of superconducting filament 341 having a first end 441 connected to the voltage terminal 361 and a second end 442 , a second length of the superconducting filament 342 having first end 443 connected to the second end of the first length 442 and a second end 444 , a third length of superconducting filament 343 having a first end 445 connected to the second end 444 of the second length 342 , and a fourth length of superconducting filament 344 having a first end 447 connected to the second end of the third length 446 and a second end 448 connected to a second voltage terminal 362 .
Accordingly, an improved device for measuring the level of liquid helium 3 in a cryogenic environment has been disclosed. The device of the present invention a longer and thicker filament 40 that provides a greater measurable voltage drop and thus a more accurate measurement of the level of liquid helium 2 present in the cryostat. Further, a thicker filament 40 improves performance and is less complicated to produce than the thinner filaments 40 of the prior art.
FIG. 3 shows an embodiment in which current would enter the cryostat 1 at 63 and leave at 64 . The voltage drop would be measured at voltage terminals 61 and 62 . FIG. 4 is identical with the exception of the increased filament 40 length.
Although we have very specifically described the preferred embodiments of the invention herein, it is to be understood that changes can be made to the improvements disclosed without departing from the scope of the invention. Therefore, it is to be understood that the scope of the invention is not to be overly limited by the specification and the drawings, but is to be determined by the broadest possible interpretation of the claims.
PARTS LIST
1 cryostat
2 liquid cryogen
3 interface between liquid and gas phase
10 connector and epoxy
20 heater
30 flexible or rigid tubing
40 filament
51 voltmeter
52 current source
53 current switch
54 rate sensor
61 positive voltage terminal
62 negative voltage terminal
63 positive current source
64 negative current source
140 two length filament
141 first length of filament 140
142 second length of filament 140
161 voltage terminal
162 voltage terminal
241 first end of 141
242 second end of 141
243 first end of 142
244 second end of 142
340 four length filament
341 first length of filament 340
342 second length of filament 340
343 third length of filament 340
344 fourth length of filament 340
361 voltage terminal
362 voltage terminal
441 first end of 341
442 second end of 341
443 first end of 342
444 second end of 342
445 first end of 343
446 second end of 343
447 first end of 344
448 second end of 344 | The present invention provides a method and apparatus for measuring the level of a liquid cryogen. The invention provides for use of a current source ( 52 ), a length, or multiple lengths, of superconducting filament ( 40 ) situated within a cryostat ( 1 ) containing a cryogenic fluid ( 2 ) and a voltmeter ( 51 ) for measuring the voltage drop across the filament ( 40 ). The invention further provides a method for using said apparatus. | 6 |
BACKGROUND OF THE INVENTION
The present invention relates to temporary workpiece supports and, in particular, to an assembly for supporting beams or framing members in a level condition as vertical and other supports are added during the framing of a surrounding superstructure.
A problem commonly encountered in construction framing is that of having to temporarily support primary load bearing beams or framing members in a level condition during the initial construction of a framed structure. The length and weight of such members make it particularly difficult to support the members in a fashion which maintains a desired elevation and level condition as the member is adjusted to its proper geometrical orientation to the frame structure and before the permanent vertical supports are secured to the horizontal supports.
For example, when framing outdoor decks or a floor system, it is frequently necessary to support multiple manufactured beams, trusses, 2×12's or possibly 4×6 or 6×10 beams, at lengths of twenty to thirty feet, in a level and plumb condition as additional framing members are attached to permanently support the primary support members. Temporary scaffolds can be erected or hydraulic equipment, such as a backhoe or front-end loader, might be used, if available to support the beams. For many projects, however, such equipment is not available or at least not at a reasonable cost in relation to projects such as the construction of a deck or pole-barn building.
Sawhorses and other low level supports do not provide sufficient height to retain the framing members, nor do they readily permit adjustment to properly establish level and plumb conditions at the members. Some of these supports are shown at U.S. Pat. Nos. 2,702,727; 2,297,316; and 5,064,156.
Lifting jacks or temporary supports have also been developed to retain cabinets in place as they are mounted to walls and ceilings. The principal concern with such supports is to obtain a desired elevation to retain the cabinet against an adjoining wall or ceiling as the cabinet is fastened in place. The supports need not establish a level and plumb condition for the cabinet. U.S. Pat. Nos. 4,340,205; 4,715,760; and 4,955,592 disclose devices of the latter type.
In appreciation of the foregoing deficiencies, the subject invention was developed to provide a stable, temporary support which when used in pairs or with other supports restrains one or more beams in a level and plumb condition. Each beam is supported in a fashion which permits adjustments to bring each beam into proper alignment to each other, any existing frame structure or the structure being assembled. The plumb, level and elevation of each support is retained throughout the process although can periodically be re-adjusted as necessary.
SUMMARY OF THE INVENTION
It is accordingly a primary object of the present invention to provide an articulating, temporary support stanchion for a workpiece such as a framing member.
It is a further object of the invention to provide a support having a telescoping stanchion which contains one or more adjustable workpiece holders.
It is a further object of the invention to provide workpiece holders which are retained to the stanchion at clamp restraints which permit the holders to pivot along two axes.
It is a further object of the invention to provide workpiece holders having means for separately adjusting elevation.
It is a further object of the invention to provide a stanchion brace which is pivotally mounted to a base support and which is fitted to the stanchion to permit adjustment of the stanchion plumb angle.
It is a further object of the invention to provide a length adjustable brace which is slide coupled to the stanchion.
It is a further objection of the invention to provide a base support that is capable of receiving a number of removable stabilizers or legs.
Various of the foregoing objects, advantages and distinctions are obtained in the following presently preferred construction. The support provides a base plate having a number of sockets which receive radially directed stabilizers. Pivotally supported to the base plate is a multi-section stanchion and the sections of which are telescopically mounted to one another. One or more workpiece supports are restrained to the stanchion with spring biased clamps. Pivot joints at the supports permit a multi-axis adjustment of each support. A length extensible brace is pivotally mounted to the base at one end and slide mounted along the stanchion at an opposite end. Adjustment of the brace varies the plumb angle of the stanchion, which angle is retained upon setting a restraint at the coupling between the brace and stanchion.
In various constructions, the brace and/or stanchion can include hydraulic cylinders to vary the extension of the brace and/or stanchion. The brace and/or stanchion can be fitted to a pivot axle formed at a base plate. The workpiece holders may also provide a screw follower attachment to the stanchion, such as at a "ball screw" collar mounted to a threaded end of the stanchion.
Still other objects, advantages and distinctions of the invention will become more apparent from the following description. To the extent various modifications and improvements have been considered, they are described as appropriate. The description should not be literally construed in limitation of the scope of the invention. Rather, the invention should be interpreted within the scope of the further appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective drawing of a pair of supports holding a pair of load bearing beams such as for an outdoor deck.
FIG. 2 is a perspective view of the base and the brace in relation to a cut away portion of the stanchion.
FIG. 3 is a perspective view to a double saddle workpiece holder.
FIG. 4 is a perspective view to an alternative support having a pneumatically extended brace and/or stanchion.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to FIG. 1, a pair of framing supports 2 of the invention are shown as they typically appear when supporting one or more load bearing beams 4 for a deck, floor system or other superstructure. Each support 2 provides a workpiece holder 6, which holders 6 are typically configured to contain a pair of saddles 8 and dimensioned to support framing members of a two inch edge width. The holders 6 support the members in a preferred level and plumb condition relative to the ground or support surface. Once the mounting position of the beams 4 is determined, permanent vertical supports 5 and the like can be readily mounted to the beams 4. Advantageously, all activities can be accomplished by a single person, without the need for heavy equipment.
Depending on the supported frame members 4, the width of the channel space 7 at each saddle 8 can be appropriately sized. That is, lengths of channel stock having a width appropriate to the beam 4 can be substituted to each holder 6 to fit a desired beam width. Although two saddles 8 are shown at each holder 6, a single saddle 8 can also be used.
Alternatively and with attention to an alternative support 9 and holder 10 shown at FIG. 4, a width adjustable saddle 11 can be used. The channel 7 of the saddle 11 is defined by a pair of overlapping angle members 12. A slot 14 and through fastener 16 are mounted to the slot 14 to permit adjustment of the spacing of the channel 7. The saddle 11 can thus be adjusted to accommodate beams 4 of a variety of widths.
The elevation of each holder 6 is determined by a clamp assembly 18 which is fitted to a vertical stanchion 20. A pair of pivot axles 22, one of which is shown at FIG. 3, extend from a clamp body 24 of each clamp 18 and mount to each saddle 8. The axles 22 provide a gimbaled mounting and permit rotation of the beams 4 and saddles 8 toward one another. The saddles 8 are thereby able to adjust to possible mis-alignment of the beams 4 as they are initially fitted to the supports 2. That is, the saddles 8 are able to rotate longitudinally to accommodate the spacing between the supports 2, without inducing tipping. The ends of the axles 22 at the coupling to the saddles 8 are presently of a stationary mount. For some applications a separate pivot may be provided to permit the saddles 8 to pivot toward and away from the stanchion 20.
A desired elevation for each beam 4 is determined with the clamp 18. Once the initial stanchion elevation is established, elevation adjustments at the holders 6 can be made by releasing a clamp arm 26, which has a serrated or knurled surface (not shown) that engages the stanchion 20, and raising or lowering the clamp body 24 and attached saddles 8, before re-securing the clamp arm 26 to the stanchion 20.
As presently constructed, the clamp 18 is constructed from a modified stationary clamp end of a conventional pipe clamp. A variety of other clamps which can be fitted to the stanchion 20 and permit vertical adjustments to the saddles 8 may alternatively be used. One alternative "ball screw" clamp 15 that can be fitted to the saddle 10 and a threaded end of the stanchion 20 is discussed below at FIG. 4.
The initial elevation of each clamp 18 is determined by the extension of the stanchion 20. That is, each stanchion 20 is constructed of multiple sections 28, 30, which telescope from one another. The stanchion 20 of FIG. 1, which is shown in detail at FIG. 3, provides a number of holes 32 which can be aligned to receive a lynch pin 34. Upon setting the extension of the sections 28, 30, the clamps 18 are adjusted to a working height which as necessary can be varied with the aid of the clamp arms 26 as discussed above.
With additional attention to FIG. 2, each support 2 is anchored at a base assembly 40 having a base plate 42 and to a bottom surface of which a number of radially directed tubular sockets 44 are fitted. The sockets 44 are formed from lengths of channel stock that are welded to the base plate 42. The sockets 44 are sized and positioned to receive a number of stabilizers 46, such as stub pieces of 2×4's or other available framing pieces, which stabilizers 46 provide support legs for each support 2.
Any number of stabilizers 46 can be fitted to each support 2 to stabilize each support 2 against undesired tipping forces. The sockets 44 can be positioned at any desired orientation to the base plate and can also be sized to receive sections of tubular pipe. Once each support 2 is positioned, fasteners, such as nails or ground pegs, can be secured through the stabilizers 46 to contain each support 2 in an established orientation.
A bracket 48 projects from the base plate 42 to support the stanchion 20 at an axle 50. The axle 50 permits the plumb angle of the stanchion 20 to be varied in relation to a brace 52 that mounts between the base plate 42 and the stanchion 20.
A variety of pivot assemblies can be provided to vary the plumb angle at the stanchion 20. An example of an alternative pivot assembly 53 and axle 54 is shown at the base assembly 55 of FIG. 4. The axle 54 is formed from the base plate as a section of material which extends across a pair of half moon cutouts 56. A slot 58 at the stanchion 60 is supported to the axle 54 and the stanchion 60 is free to rotate as the plumb angle is established at the brace 80.
A turnbuckle brace 52 extends between the stanchion 20 and a second pivot bracket 62. A fastener 64 serves as a pivot axle to one threaded end 66 of the brace 52. An opposite threaded end 68 is secured to a fastener 70 of a clamping collar assembly 72 at the stanchion 20. The fasteners 64 and 70 provide two pivot points which facilitate the plumb adjustment of the stanchion, and which accommodate the adjustment of the stanchion 20 to uneven support surfaces. Upon rotating a body 74 of the turnbuckle brace 52, the brace 52 extends and retracts to accommodate changes in the plumb angle of the stanchion 20.
The collar 72 includes a pair of semi-circular pieces 74, 76 which mount about the stanchion 20. The fasteners 70 and 71 secure the pieces 74, 76 together and once set, retain the collar 72 to the stanchion 20. Depending upon the adjustments to the brace body 74, the collar 72 is raised or lowered.
During the initial setup of the support 2, the collar 72 is loosely secured to the stanchion 20 and the brace 52 is adjusted to set the stanchion 20 plumb to the ground or support surface. Once a plumb condition is established, the fasteners 70, 71 are set and the condition is retained. Further adjustments can then be made at the holders 6 to establish a proper elevation and level condition.
Returning attention to the alternative support 9 at FIG. 4, the stanchion 60 is supported at a brace 80 which is constructed from a hydraulic or pneumatic cylinder 81. A cylinder end 82 is pivotally supported to a bracket 84 at the base plate 86 and a piston 88 is secured to a collar 72 at the stanchion 60. Appropriate supply and return lines 90, 92 extend from a controller 94 to vary the extension of the piston 88. With the setting of an appropriate extension, the collar 72 is set to fix the plumb condition of the stanchion 60.
In lieu of a lynch pin mounting, a second cylinder 81 is also fitted within the stanchion 60 to upper and lower telescoping sections 96, 98 to extend and retract the section 98 as desired via the controller 94.
As mentioned, the holder 10 of FIG. 4 also provides an adjustable "ball screw" clamp 15. Ball screws are generally known and are available from a number of suppliers. The clamp 15 is constructed from a modified ball screw and includes an inner race 100 which is threaded to a threaded extension 61 of the stanchion section 98. An outer race 102, which is separated from the inner race by a number of ball bearings (not shown), contains a pair of axles 104 and a set screw 106. The end of the axles 104 mounted to the race 104 permit longitudinal rotation of the saddles 8. Fasteners at the opposite end of the axles 104 fit through oversized holes in the saddles 8, 11 loosely retain the saddles 8, 11 and permit rotation toward and away from the stanchion 60.
The clamp 15 advantageously supports the saddles 8, 11 in a screw follower fashion to the stanchion 60. That is, the elevation of the holder 10 can be adjusted by either rotating the holder 10 and outer race 102 or by rotating the threaded extension 61. Prior to placement of the beams 4, the initial position of the holder 10 is established by rotating the holder 10. Once the beams 4 are set and which stabilizes the races 102, 104 against inadvertent rotation, the extension 61 is rotated with the aid of a handle 108 that mounts to the threaded extension 61 at the section 98. The beams 4 can thereby be adjusted to a final desired elevation with relative ease by merely rotation the stanchion 60, which rotation is also accommodated by the piston at the cylinder 81.
Although particular arrangements of adjustable braces 52, 80, stanchions 20 and 60, and clamps 18 and 10 are shown, it is to be appreciated different combinations can be included in a preferred support.
While the invention has been described with respect to a presently preferred construction and considered modifications and improvements, it is to be appreciated still other constructions may be suggest to those skilled in the art. The invention therefore should be broadly interpreted to include all those equivalent embodiments within the spirit and scope of the following claims. | An articulating and telescoping assembly for temporarily supporting construction framing members. A base includes a number of radially directed sockets which receive detachable stabilizers. A telescoping stanchion pivots at the base and supports a gimbaled workpiece holder having support saddles, which holder is also vertically adjustable along the stanchion. A length adjustable brace pivots at the base and is vertically adjustable along the stanchion at a clamp to determine a plumb angle of the stanchion. Alternative constructions of the workpiece holders, holder support clamp, brace, stanchion pivots, and stanchion extenders are disclosed. | 4 |
CROSS REFERENCE TO RELATED APPLICATIONS
This is a continuation of my copending application entitled PROTEIN PRODUCT AND METHOD AND APPARATUS FOR FORMING SAME, filed Dec. 9, 1966, Ser. No. 600,471, which in turn is a continuation-in-part of my application entitled PROTEIN PRODUCT, filed July 10, 1964, Ser. No. 381,853, both now abandoned.
BACKGROUND OF THE INVENTION
This invention relates to a method and apparatus for producing a meat-simulating product from protein-containing vegetable materials, particularly soybean meal, and to a meat-simulating product produced from protein-containing vegetable materials.
During recent years, extensive research and development efforts have been applied toward the development of meat-like or meat-simulating food materials prepared from protein-containing vegetable substances. As is known, the chief nutritional value of meat is due to its protein content. However, although meat is a most desirable source of protein, from the consideration of eating pleasure, the production of meat is actually relatively inefficient, in terms of feed input to food output. Furthermore, certain crops such as soybeans, provide inexpensive by-products which have a high percentage of potentially available protein, but which are not normally palatable and/or edible.
One excellent technique for producing meat-simulating edible foods from protein-containing vegetable materials such as soybean meal is taught in U.S. Pat. No. 2,682,466 to Boyer, entitled HIGH PROTEIN FOOD PRODUCT AND PROCESS FOR ITS PREPARATION, issued June 29, 1954. This technique involves the creation of a large number of small diameter spun fibers which are then gathered into bundles or "tows" and thence formed into various type edible products with subsequent operations. While these products are of high quality, the process is complex and expensive, so that the products must be priced in the general range of the corresponding actual meat products. Moreover, the product output per expense unit of equipment is relatively small.
Consequently, there has existed a definite need for a relatively inexpensive method of treating protein-containing vegetable materials to produce a product which would bear resemblance to actual meat in appearance, physical structure and texture, and chewing and mouth-feel characteristics, and that could be practiced sufficiently inexpensively that the product could be priced at a small fraction of the price of actual meat products.
It is a primary object of this invention, therefore, to provide a unique relatively inexpensive method of treating protein-containing vegetable materials to convert them from a generally unpalatable substance to a highly palatable and desirable product that is restructured to resemble meat in appearance, physical structure and texture, chewing characteristics, and nutritional value. Further, these properties and characteristics can be controllably varied quite readily by the method.
Another object of this invention is to provide a novel method of producing highly nutritional, highly palatable meat-simulating food products from protein-containing vegetable materials, particularly soybean meal, such that the method is capable of relatively high production, continuous product output per expense unit of equipment. Moreover, the amount of protein in the product can be greatly varied as desired.
Another object of this invention is to provide a novel method of producing from protein-containing vegetable material a meat-simulating product which can be rapidly and inexpensively dried as it is produced, to be capable of conventional packaging for extended unrefrigerated storage in its dry condition. Further, the stored product can be rapidly rehydrated in a matter of seconds, in a very simple manner, without cooking, heating, autoclaving, or steaming, but rather merely by the addition of aqueous liquid.
Another object of this invention is to provide a novel highly palatable, highly nutritional meat-simulating food product from protein-containing vegetable materials, particularly soybean meal, capable of being dried, packaged, shipped, and stored for substantial periods, without refrigeration, and capable of rehydrating in moments merely by the addition of moisture, and without requiring cooking, autoclaving or pressurizing.
Another object of this invention is to provide, from a protein-containing vegetable material, particularly soybean meal, a meat-simulating food which has a fibrous lace network structure appearing and acting somewhat like the muscle fibers in actual meat, but which product costs only a fraction of that of meat.
Another object of this invention is to provide from protein-containing non-meat material, a meat-simulating product capable of inexpensive and rapid dehydration, and of subsequent simple and rapid rehydration, to effect a meat-simulating foodstuff having all the beneficial characteristics of meat but at a cost of about one-fifth of that of meat.
Another object of this invention is to provide novel extrusion apparatus capable of continuously, rapidly, and reliably converting protein-containing vegetable material, particularly soybean meal, into a restructured, excellent quality, meat-simulating product having a fibrous network structure resembling the muscle fiber structure of meat.
These and several other objects of this invention will become apparent upon studying the following specification in conjunction with the drawing.
DESCRIPTION OF DRAWING
The drawing is a side elevational, sectional view of the basic extrusion apparatus preferred for practicing the invention.
DETAILED DESCRIPTION
The concept of this invention pertains broadly to a unique processing treatment of protein-containing products to obtain a meat-like food material, the concept being intended for the treatment of protein-containing vegetable materials, with by far the most beneficial results being achieved when the novel concept is applied to soybean meal, in contrast to other vegetable protein materials such as peanut meal, corn meal, and cottonseed meal. In fact, by properly treating soybean meal according to this invention, a top grade, expanded product containing a fibrous network simulating the texture of meat tissues is obtained.
Soybean meal is the product resulting after oil is extracted from comminuted soybeans and is commonly called defatted soybean flakes. Soybean meal usually is in a flake-type particulate form. It could, however, be ground into a finer form such as powder. These various physical sizes and forms are broadly considered with the term soybean meal. In order to practice the present invention, it is important that the oil be extracted by chemical solvent techniques, such as with hexane rather than by mechanical pressing techniques, because the meal fed to the extruder in this process should be substantially free of oil. If mechanical pressing techniques are employed, the chemical solvent technique is subsequently employed before proceeding with the practice of this invention.
Specifically, it has been found that if the soybean meal is substantially free of residual oil, for example about 0.5% or less by weight, very excellent meat-simulating, fibrous formation occurs during extrusion, as well as the product exhibiting a controlled and excellent rate of expansion as ejected from the extruder. If the residual oil content in the soybean meal is present in a minor amount, e.g., about 2% by weight or less, a usable product can be obtained by the novel process, since some limited fibrous structure forms, but the fibrous structure is poor in comparison with that from substantially oil-free soybean meal. Furthermore, if the residual oil content is much above the minor amount, for example, about 5% by weight of the soybean meal, very little or no fibrous formation occurs. No other vegetable oil or animal oil or fats should be added to the soybean meal prior to extrusion. Either of the terms "oil" or "fat" are used herein to encompass what might be considered as vegetable oils and fats, or animal oil and fats, whether liquid or solid in form.
Another important criterion, which has been determined for the soybean meal composition, is the carbohydrate content. This component has an effect on the amount of product expansion. In this regard, it should be noted that, for an optimum meat-simulating product to be formed, the product must have an interconnected fibrous lace network formation that appears, feels, and acts in some respects like muscular meat fibers. For this to occur, the product should be controllably expanded or puffed when ejected from the extruder. However, the expansion is limited so that it is not unduly puffed. This excessive puffing destroys or at least seriously limits the formation of the interlaced nature of the fibrous product. Regarding this factor, it has been experimentally determined that the carbohydrate content, if present in an amount over a certain minimum, increases the amount of expansion of puffing sufficiently that the fibrous structure is at least partially or completely broken up and destroyed. Specifically, the natural carbohydrate content of about 35% by weight should not be increased by any more than about 5% by weight added carbohydrate. For example, if the carbohydrate content is increased by about 15% by weight added carbohydrate, fibrous formation is normally prevented or destroyed.
Prior to being fed into the extruder, the soybean meal is mixed with a predetermined amount of aqueous liquid, such as plain water, in order to effect a necessary mininum moisture content. The soybean meal and moisture are mixed into a generally homogeneous mass prior to being fed through the extruder. The moisture content can generally vary between the minimum of about 20% by weight of the total mixture to a maximum of about 40% by weight of the total mixture. If the moisture content is varied within this range from the low amount to the high amount, the temperature of the mixture in the meal should be varied as specifically explained below. This moisture assists in the chemical changes that occur in the extruder, is essential to the controlled expansion of the product leaving the extruder, and probably has other functions which are not fully understood. Preferably, the moisture content is between 30%-40% if the sodium hydroxide is not added as explained hereinafter. If it is added, the preferred moisture content is 23%-34%. At any rate, the moisture is an essential component in the soybean meal mixture.
Associated with the moisture addition is the control of the pH of the soybean meal. Control of this pH is also significant in this process. The normal pH of soybean meal after oil extraction is usually within the range of 6 to 7, typically 6.9 or so. Although experimentation has shown that soybean meal of widely varying pH can be beneficially extruded according to this process, it has been determined that the resulting product varies greatly in characteristics and qualilty with variation in pH. Specifically, it has been determined experimentally that is is preferably to have the meal just slightly acidic or slightly basic. That is, it is broadly desirable to keep the pH within the broad range of 5 to 12 since, below 5 and above 12, very poor fibrous formation occurs. Of this broad range, it preferably should be kept within a pH range of 6 to 9. Experimentation over an extended period of time shows that the best fibrous formation occurs when the meal is slightly basic, within a pH range of 7.5 to 8.7.
Control of this pH is achieved by adding a common acid such as hydrochloric acid, phosphoric acid, a base such as sodium hydroxide or other common edible electrolytes, to the aqueous liquid prior to mixing this aqueous liquid with the soybean meal to form the moist mixture. The above-noted experimentation clearly shows that the addition of an hydroxide is particularly beneficial since it apparently has a function in addition to acting as a pH control material. The amount of sodium hydroxide added should be sufficient to raise the pH to about 8.2-8.7, with 8.6 being optimum. It appears to have a beneficial chemical action on the complex protein molecular structure to catalyze the reaction. Whatever the technical explanation, the addition of sodium hydroxide causes a substantially better grade of fibrous formation in the resulting extruded product, and greatly eases control of the process. It further enables the protein content to be varied within a wider range without preventing excellent fibrous formation, as explained hereinafter. If the mixture formed from the aqueous solution of sodium hydroxide and the soybean meal is allowed to set and "cure" for several minutes prior to introduction to the extruder, these beneficial results are even further assured. Hence, control of the pH of the mixture, particularly with hydroxyl ions, is very significant to obtain a top quality product.
Another controlling factor, in addition to the fat content, carbohydrate content, moisture content, and pH of the soybean meal, is the protein content of the composition. Typically, soybean meal resulting from conventional oil extraction processes has a protein content of about 44% or 50% by weight, depending on the degree of refinement. Normally, a protein content of less than about 44% is not encountered, although this process is intended to encompass vegetable materials having a protein content less than this. A typical protein concentrate which can be added to increase the protein is commercially termed "isolated protein". Experimentation with this process shows that a soybean meal with a protein content of about 50% by weight produces the most desirable product, with optimum fibrous network formation and optimum expansion. Hence, preferably the operation is conducted on this material. However, the method does produce some fibrous formation in soybean meals having a protein content of about 30%, but below this value, the product is not very worthwhile. Furthermore, the protein content can be increased substantially about 50%, up to about 75%. Above this, the resulting product tends to have a gummy characteristic which is not desirable. Hence, preferably the protein content in the soybean meal should be between about 30% and 75% by weight, with the preferred amount being about 50% by weight.
The addition of a hydroxide, preferably sodium hydroxide, has a definite effect on the usable range of protein concentration which can be employed while operating with a minimum of production problems and producing a highly desirable product.
When a soybean mixture having the characteristics described above has been prepared, it is fed into an extruder assembly where it is subjected to elevated temperature and pressure and the extruder, as illustrated, is equipped with a restrainer plate 7. The rotating screw 5, in combination with this restrainer plate with its restricted outlet 11, creates a high pressure on the material in the extruder. The particulate, moist meal fed in changes form until it finally flows in a generally fluid manner even squeezing around the outer periphery of the screw in a recirculating fashion, to cause a severe mechanical working of the substance. The pressures in the extruder are elevated to several hundred psi, and normally fall within the range of about 300-600 psig. Part of the pressure is caused by the screw and restrainer plate. Part of the pressure is due to the high temperatures which result both from friction between the flowing product and components of the extruder, and from heat that is purposely added to the outside of the extruder in normal operation. This added heat is preferably obtained by passing steam through the forward or front annular jacket 15 within the extruder housing, around, but separated from, the forward end of the extruder chamber. The amount of steam heat applied is controlled by typical valving techniques in a manner to obtain temperatures which are not sufficiently high as to cause the product to scorch or burn, but which are sufficiently high to cause the desired chemical and physical reactions within the material. The amount of added heat to do this will vary with the particular extruder construction, but can be readily determined by trial and error during the initial stages of operation of the equipment.
The temperatures reached by the material in the extruder must be above 212° F. and actually should be considerably higher, within a certain specific range in order for a meat-simulating product with good fibrous structure to be formed. This varies with variations of the other mixture characteristics of which the most significant is moisture content. As the moisture content increases from about 20% to about 40%, the temperature may be decreased from about 310° F. to about 270° F. Below about 270° F., fibrous formation is poor. The preferred temperature range is about 270°-300° F., with optimum results having been obtained at about 280° F.
In addition to the steam jacket for adding heat, an annular cooling jacket 13 surrounds the rear portion of the extruder chamber. This has been found desirable in normal operation to maintain lower temperatures in the initial stages of mechanical working in the extruder. Cooling prevents the product from overheating to become scorched before it exits from the extruder. Again, the amount of cooling water and the temperature to cause the desired cooling effect will vary, but can be readily determined by trial and error during initial stages of operation.
The product outlet means from the extruder also includes a smaller secondary chamber into which the material discharges from orifice 11. The output from this second smaller chamber is also restricted by a die nozzle outlet 19. It has an area smaller than or about that of the restrainer or restrictor outlet 11. Without this two-stage restriction set up, it is extremely difficult to obtain acceptable fibrous formation in the product. In fact, another feature of the extruder has been found to be important to top quality fibrous formation when employing the cooperative makeup explained previously. This feature is the positioning of an elongated pipe member 17 between restrictor outlet 11 and die outlet 19. It has a diameter substantially smaller than the diameter of the extruder chamber to which it is attached, such diameter ratios normally being about 1/6 to 1/10. The product is longitudinally passed through this member while still radially restricted, along the length of the tube, under high pressures and at the elevated temperatures prior to being ejected into the lower pressure and temperature of the atmosphere. The tube has a length of about 8 to 12 times its internal diameter. In actual dimensions, a representative example of these components would include an extruder chamber diameter of about 5 inches, with a length of 3 to 4 feet or so, and a tube diameter of 3/4 of an inch and length of about 6 inches.
The exact scientific explanation of the functions of this hollow pressure tube into which the material is ejected prior to ejection to the atmosphere, cannot be given; but the efficacy of it is very definite and significant. In fact, with some soybean meals where the protein content is low, only very poor fibrous formation occurs unless this tube extension is employed.
OPERATION
In operation, the soybean meal obtained by solvent extraction of oil from the soybeans is checked so that it has only a minor oil content, i.e., less than about 2%, and preferably is substantially oilfree, i.e., less than about 0.5% by weight of the meal. If the content is greater than this, the soybean meal must be treated with a chemical solvent such as hexane to extract the excess oil. Further, no other oil or fat material, animal or vegetable, is added to the meal prior to extrusion.
If desired, the meal may be ground more finely than the small flakes in which it normally occurs from the extraction process, but experimentation along this line indicates that this is not necessary.
Moisture is then added to the soybean meal, normally in the form of water, to bring the moisture content within the range of 20% to 40% by weight of the resulting mixture. The moisture and meal are mixed into a homogeneous mixture.
If the pH of the meal is to be adjusted, for example, to place it in the preferred range of 7.5 to 8.7, it is adjusted by adding the noted type of reagents, preferably. A basic material containing hydroxyl ions, preferably sodium hydroxide can be added by adding it to the water prior to moistening the meal. Enough is preferably added to bring the pH to about 8.6. If it is desired to adjust the pH into the acidic range, acid is added to the water and thus to the meal in the same fashion.
When the mixture is prepared and ready for the extrusion operation, it is fed into inlet 3 while the extruder screw 5 is rotated at a substantial speed, for example of about 150 rpm. During this operation, steam is passed through forward jacket 15, and normally, cooling water is passed through rear jacket 13. The meal mixture is advanced in the extruder by the screw while its temperature is increased to within the range of 270°-310° F. by the steam heat added, by the mechanical working friction, and possibly by the chemical changes occuring. Since the screw tends to advance the material faster than it can be passed through the restricted outlet means, the pressure builds up in the chamber to several hundred pounds per square inch, usually about 300-600 psi, while the product is severely mechanically worked in the extruder. By the time the mixture reaches the restrictor plate, it is in the form of a flowable substance which is forced from the main extrusion chamber, after a retention time of usually 30-40 seconds, through restrictor plate outlet 11 into the supplemental chamber. The material remains under elevated pressures and temperatures as it is advanced by pressure differential through the secondary chamber through the elongated tube, to die outlet means 19. As it emerges from outlet 19 under the high internal pressures into the much lower atmospheric pressure, the super heated moisture paritally flashes off by evaporation to cause product expansion and partial cooling. If the product is being processed properly, it emerges in the form of a continuous, elongated, expanded, fibrous member which is restructured and which can be kept in its continuous form or severed into individual chunks as it emerges by any ordinary cut-off means. The expanded product is very porous, and has a fibrous network or lace structure which somewhat resembles that of actual meat tissue fibers. If the product is kept moist in its freshly extruded condition, it can be directly used for simulated meat. Normally, it is desirable to add coloring materials to the product before extrusion, and to add flavorings before or after extrusion. The product is very nutritious as it emerges, is sterile, palatable, and wholesome. If portions of the product are pulled apart with one's fingers, the texture appears and acts somewhat like that of meat.
Instead of storing the product in its moist condition, wherein it should be kept under refrigeration or in hermetically sealed condition, it can be easily and quickly dried merely by passing it through a conventional drying chamber so that it can be packed and stored in a more convenient fashion. Its porosity enables it to dry quickly enabling simple and direct packaging in its dried form in a manner similar to cereal products. An important feature of this product is that it can be completely rehydrated extremely rapidly, i.e., in a few seconds, with great ease, i.e., merely by adding an aqueous liquid. Thus, whenever it is to be eaten, the dried chunks are rehydrated by mixing with aqueous liquid such as pure water, which is preferably warm so that it would be at a desirable eating temperature. The rehydrated product exhibits all of the desirable noted meat-simulating characteristics. No cooking, autoclaving, or pressurizing is necessary for rehydration.
The resulting product can be used for human food, e.g., "health foods", or, due to its cost being only about 1/5 or less of that of conventional meat, it can be economically used for pet foods. Palatability and nutrition tests have proven it to be an excellent and desirable food for pets or other animals. The material can be employed in a variety of forms, can be colored and/or flavored in a variety of fashions, and can be controllably varied in characteristics, to resemble various types of meat materials. By controlling the rate of feed of the product through the extruder, temperatures, degree of expansion, additives, protein content, moisture content, and the like, the character of the product can be widely varied while retaining its fibrous meat-simulating texture. The possibilities of this food product are many.
To assure that one having ordinary skill in the art will understand this invention, the following detailed illustrations are provided. It will be realized that literally thousands of various experimental runs have been made after discovery of the basic invention involved, over an extensive period of time. These were done in order to determine the critical limitations of the composition and method steps, and the operational criteria. To record the data of all of these runs here would unduly lengthen this document and would serve no good purpose.
ILLUSTRATION 1
Seventeen pounds of soybean meal, after oil extraction by hexane were employed. It had a protein content of 50% by weight of the soybean meal, and a fat content of 0.5% by weight. This soybean meal was mixed with 2600 cc. of water, having sufficient sodium hydroxide added to the water to cause the mixture of moisture and soybean meal to have a final pH of 7.5. The mixture was allowed to set and cure for 5 minutes to obtain a good water and sodium hydroxide dispersion, penetration, and reaction. The mixture was then fed into the extrusion device illustrated, with steam being supplied to jacket 15 at a pressure of 20 psig and cooling water at room temperature being constantly passed through jacket 13. The opening in restraining plate 7 was 1/4 inch in diameter, with screw 5 being rotated at 150 rpm. The mixture was thus mechanically worked within the extruder at a temperature of around 300° F., with the pressures varying somewhat but being generally above 300 psig. The material was continuously passed through the extruder, passing through the elongated tube and out an extruder nozzle having a size of 3/8 × 1/8 inch. The reaction time of the material within the extruder was about 30 seconds. The mixture was ejected from the nozzle in a continuous stream, and was a coherent fibrous structure which expanded with passage through the nozzle, to form a porous structure. The product, when removed, had a fibrous meat-like texture of excellent quality.
ILLUSTRATION 2
Another run similar to Illustration No. 1 was made, but in this instance the pH was adjusted to the acidic side with hydrochloric acid with the soybean meal being mixed with 1,000 cc. of water to which 15.5 grams of concentrated hydrochloric acid had been dissolved. The materials were mixed for approximately 13 minutes, and then an additional 1,850 cc. of water were added, with the resulting pH of the mixture being approximately 6.6. The mixture was then fed to the extruder, and passed through the extruder at pressures generally of about 400 psig and at a temperature of about 300° F. The resulting product had good fibrous formation, but inferior to the fibrous formation of Illustration No. 1, when the pH was on the basic side.
ILLUSTRATION 3
This operation was just like that in Illustration No. 1 above, except that the moisture content was about 25% and the pH was not adjusted. The product was completely acceptable, and the fibrous formation was good but not as good as when the pH was above 7.
ILLUSTRATION 4
The meal was substantially the same as that used in Illustration No. 2, but the pH was adjusted in the mixture to 5.5 by adding 52 grams of hydrochloric acid in solution in 2,300 cc. of water. Although fibrous portions did form, they did not bind the product together in the effective manner of previous runs, and fibrous formation was less than previously. In additional experiments, it appeared that the rate of fibrous formation tended to fall off quite rapidly as the pH is lowered below this amount.
ILLUSTRATION 5
In this illustrative run, the soybean meal was of the type described in Illustration No. 1. The mixture, however, was formed by adding 50 grams of sodium hydroxide and approximately 1,000 cc. of water were mixed with the soybean meal to obtain a resulting mixture pH of 8.6, after 1,300 cc. of additional water was subsequently added. The product was then extruded through the equipment illustrated, with the ultimate product exhibiting very substantial puffingg puffing but yet with complete coherence by reason of the fibrous network, and with excellent meat-simulating characteristics. It dried quickly and easily at temperatures above 212° F. to evaporate excess moisture. It rehydrated within a few seconds merely by adding warm water.
ILLUSTRATION 6
Parallel runs were made on soybean meals containing approximately 2% soybean oil, 2% animal fat, and 5% soybean oil in the meal. Seventeen pounds of the 50% protein soybean meal was mixed with 2,300 cc. of water in each instance and 7.5 grams of sodium hydroxide to bring the pH within the range of just above 7, but under 8.The meal was then extruded through the equipment as previously, with the result being that the product from the meal containing 2% soybean oil and the product from the meal containing the 2% animal fat exhibited some fibrous formation but of a generally poorer quality, while that containing the 5% soybean oil exhibited no fibrous formation at all. In fact, in this latter instance, the particulate meal was discharged in much the same form in which it went into the extruder.
ILLUSTRATION 7
Parallel runs were made on the 50% protein soybean meal containing 5% carbohydrate and 15% carbohydrate in the form of corn starch. The resulting products included a product of the 5% mixture which had poor fibrous formation, with excessive puffing breaking up the fibrous network and the 15% product having only puffing with no fibrous formation occurring so that it did not have meat-simulating characteristics.
ILLUSTRATION 8
Parallel experiments employing protein contents of 44% and below, run at various pH levels, at varying extruder temperatures and pressures exhibited differing types of fibrous formation. Experiments with and without the extruder tube extension were made.
As stated previously, the number of illustrations could be endlessly listed, but it is believed that, with the above illustrations and discussion of the criteria and critical factors involved, anyone having ordinary skill in this art could adapt the novel method and apparatus to various situations to obtain the desired type of product merely by a few trial-and-error variations in the moisture content, pH, fat or oil content, carbohydrate content, extrusion pressures and temperatures, restrainer plate restrictions, extrusion die nozzle sizes, and the like. In fact, it is realized that variations in these and related factors could be readily made within the concept taught herein. Hence, the invention is intended to be limited only by the scope of the appended claims and the reasonably equivalent methods, apparatuses, and products to those defined therein. | A method of producing an expanded product which resembles meat, directly from soybean meal itself, including the steps of utilizing soybean meal that has substantially all the fat removed to an amount of about 5% or less, and preferably 2% or less, moistening the soybean meal such as mixing the soybean meal with water to obtain a moisture content of about 20%-40% by weight, controlling the pH within the range of 5 to 12, preferably 6 to 9, preferably adding an edible pH altering electrolyte while maintaining the controlled pH, and then simultaneously, mechanically working, heating above 212° F., and pressurizing the moistened soybean meal in an extruder chamber sufficiently to cause continuous conversion of the meal to a flowable substance, and forcing the substance through and out of restricted orifice means to expand it into a lattice network structure having resilience, body strength, and appearance approaching that of meat. | 0 |
BACKGROUND OF THE INVENTION
The present invention relates to a new and improved construction of a rolling device or roller mill which is of the type comprising at least one controlled deflection roll or adjustment roll--also referred to in the art as a roll with bending compensation--equipped with a roll shell rotatable about a support. The roll shell is supported upon support elements arranged between the support and the roll shell and movable relative to the support in at least one pressure plane in such a manner that the support elements are suitable for producing contact or lifting movements, and a support arrangement of the rolling device comprises vertical side elements at which there are supported the rolls.
Rolling devices or roller mills of this type, which can be constructed for instance according to U.S. Pat. Nos. 3,884,141, 3,921,514 to German patent No. 2,325,721 and can contain controlled deflection rolls of the type disclosed in U.S. Pat. Nos. 3,802,044 and 3,885,283, possess the considerable advantage that they do not require any external pressing or contact mechanism, such as, for instance, lever mechanisms having hydraulic or pneumatic cylinders or rubber bellows. As a result they are particularly simple in construction and space saving.
SUMMARY OF THE INVENTION
It is a primary object of the present invention to further improve upon the heretofore known rolling devices or roller mills with the aim of not only further mechanically simplifying the same, but additionally at the same time obtaining simplified conditions for the operation and the installation and dismantling of the rolls.
The inventive rolling device, by means of which this objective can be attained, is manifested by the features that the side elements have open cutouts or recesses or equivalent structure extending transversely with respect to the axial direction of the rolls. These open cutouts are suitable for the reception of bearing blocks or the like for the rolls and possess support surfaces for the support thereof. The cutouts are closed by closure elements detachably secured to the side elements and suitable for transmitting forces.
In this way there is obtained a particularly suitable and inexpensive, and thus, robust support arrangement, wherein, as already mentioned, the rolls, following removal of the closure elements, can be laterally or upwardly dismantled in a simple fashion.
The closure elements serving to take-up the traction or tension force can have contact or support surfaces extending in the direction of the traction or tension force. At the region of the contact surfaces there are arranged fixation elements intended to take-up thrust forces. In this way there is realized a particularly simple construction of the closure elements, since the otherwise required expensive exact machining or working of mutually interengaging or interacting surfaces needed for taking-up the tension forces is dispensed with.
According to a particularly advantageous construction the fixation elements can be cylindrical or slightly conical pins, the axis of which extends in the contact surface of both elements, i.e., the closure and side elements and is arranged perpendicular to the force direction. The pins are attached at one of the elements or parts to be interconnected. Such type pins can be easily arranged, since they only require a bore which need be guided with no particular accuracy. The pins are particularly well utilized for the purpose of force transmission, since they perform a support or carrying function not simply at their circular cross-section rather along their entire length. Finally, they possess the further advantage, owing to their domed or arched configuration, that during a subsequent assembly of the equipment they position the closure elements at the contact surfaces and thus facilitate the assembly or erection work.
Moreover, at least one closure element can extend over at least two cutouts or recesses which are directed towards the same side. This appreciably simplifies the construction of the rolling device or roller mill. Additionally there are obtained strength advantages since a common closure element is stronger and more rigid than, for instance, two adjacently arranged separate closure elements.
Preferably the side elements can consist of solid material of essentially constant thickness, can be rectangular and have essentially linear or straight end surfaces.
Although such simple and robust shape also can be fabricated of cast iron, it is particularly suitable for fabricating the side elements from rolled steel material, the end surfaces can be produced by gas or flame cutting, and it is only necessary to machine the contact or support surfaces for the bearing blocks and the closure elements. In this way the equipment can be particularly simplified and rendered inexpensive to manufacture, and additionally there are obtained especially rigid side elements.
Moreover, devices such as for instance scrapers, which are preferably associated with the individual rolls, can be arranged in each case at the side of the side elements which face away from the opening of the cutout in such a manner that the rolls can be dismantled without having to dismantle such device. Consequently, there is obtained the particularly important advantage that the scraper or similar or other devices, such as, for instance, measuring devices, control devices and so forth, can remain in their position during dismantling of the rolls .
The bearing blocks or bearing means of at least one roll can possess a number of contact or support surfaces having different spacing with respect to the axis of the roll. In this way it is possible to take into account in a most simple manner different diameters of the rolls as delivered or changes in the roll diameter following roll grinding.
Furthermore, it is possible to construct the contact or support surfaces of the bearing blocks for at least one roll at parts movably mounted at the side elements, and which are supported against the action of the roll force with a pre-bias or pre-stress by means of elastic elements. These parts bear upon impact or stop surfaces. In this way there is obtained a simple safety or protective device against overloading the rolls, if, for instance, a foreign body or the like should become deposited or entrapped between the roll surfaces.
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 references to the annexed drawings wherein:
FIG. 1 is a front view, partly in section and with removed parts to enhance clarity of the illustration, of a rolling device or roller mill incorporating two rolls;
FIG. 2 is a view of the rolling device shown in FIG. 1, looking in the direction of the arrow II of such FIG. 1, with the opposite side structured essentially like the side shown;
FIG. 3 is a view corresponding to the showing of FIG. 2 of the bearing block or bearing means of the lower roll and shown on an enlarged scale;
FIG. 4 is a cross-sectional view of the arrangement of FIG. 1, taken substantially along the section line IV--IV thereof; and
FIG. 5 is a side view of a rolling device or roller mill, corresponding to the showing of FIG. 2, equipped with four rolls.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Describing now the drawings, the rolling device or roller mill illustrated by way of example in FIG. 1, which for instance can be a calender for smoothing a paper web, will be seen to comprise a solid roll 1 and a controlled deflection roll 2. The controlled deflection roll 2, as is known in this art, may be actuated, for instance, by an hydraulic pressurized medium and can be constructed according to the teachings of U.S. Pat. Nos. 3,802,044 and 3,885,283, to which reference may be readily had and the disclosure of which is incorporated herein by reference.
The controlled deflection roll 2 contains a fixed, non-rotatable support 3 in which there is guided hydraulic pistons 4 defining support elements upon which there is hydrostatically mounted a roll shell 5 rotatable about the support 3. The not particularly illustrated cylinder bores in which the hydraulic pistons 4 are guided have infed thereto the hydraulic pressurized fluid medium by means of a line or conduit 6 from a not particularly illustrated pump installation or the like. The hydraulic medium is withdrawn by means of an outfeed or withdrawal line 7 from the intermediate space 9 between the support 3 and the roll shell 5.
As best seen by referring to the sectional view of FIG. 4, the roll shell 5 is provided at its ends with guide disks 8 or equivalent structure, having cutouts 10 provided with guide surfaces 11 which are guided along similar substantially parallel guide surfaces 12 of the support 3. The guide disks 8 are mounted in ball bearings or equivalent structure 13 at the roll shell 5. This construction, which is known from the aforementioned U.S. Pat. No. 3,885,283, enables an upward movement and a lowering movement of the roll shell 5 under the action of the hydrostatic pistons 4, so that there can be dispensed with an outer contact or press mechanism for the roll 2, for instance hydraulic cylinders or pneumatic bellows or the like.
As further seen by referring to FIGS. 1 and 2, the rolls 1 and 2 are mounted in a support or frame arrangement which comprises side elements 14 which are attached in any suitable manner upon base plates F which, in turn, in known manner are anchored in not particularly illustrated fashion at the floor or other support surface.
As particularly well seen by referring to FIG. 2, the rolls 1 and 2 are provided with bearing blocks or bearing means 15 and 16 which are arranged in cutouts or recesses 17 and 18 of the side elements 14, which are open upwardly or towards the side and extend essentially perpendicular to the axial direction O of the rolls. The bearing blocks 15 at the opposite ends of the solid roll 1 are provided with slide or antifriction bearings 20 in which there are mounted the rotatable bearing pins or journals 21 of the roll 1. The opposed ends of the support 3 are supported in openings or bores 22 of each bearing block 16, and they are prevented from rotating relative to the bearing blocks by any suitable and therefore not particularly illustrated arresting or blocking means. Each bearing block 15 is supported at its associated side element 14 upon a machine worked bearing or contact surface 23 and is prevented from carrying out lateral movement by a fitting or adjustment spring 24 or equivalent structure. The bearing block 15 is held from above by means of a yoke 25 or the like and which is fixedly threadably connected at the side element 14 by means of screws or threaded bolts 26 or equivalent fastening expedients and forms a closure element enclosing the cutout or recess 17.
The bearing block 16 is supported upon a part or member 27 which is movably guided at the side element or portion 14. Part 27 has a support or contact surface 28. This part 27 is supported by suitable elastic elements, such as plate springs 30 against stepped stop or impact surfaces 31. The plate springs 30 have a spring force which is larger than the maximum permissible operating force between the rolls 1 and 2 and enables lift-off of the rolls from one another when this force is exceeded. Screws or threaded bolts 32 or equivalent devices are provided for supporting the bearing block 16 at the related part or member 27. Lateral shifting of the bearing block 16 is likewise prevented by means of fitting spring 24.
As best seen by referring to FIG. 3, each bearing block or bearing means 16 for the support 3 of the roll 2 is constructed such that its four lateral contact or support surfaces 33, 34, 35 and 36 possess a different spacing A, B, C and D from the axis X of the bore 22. By appropriately selecting the axial spacing A, B, C or D there can be set or adjusted different spacings of the support 3 from the axis of the roll 1, so that fabrication tolerances of the rolls or changes of their diameter following post grinding thereof can be taken into account.
In accordance with the illustration of FIG. 2 the cutouts or recesses 18 for mounting the lower roll 2 are laterally closed by closure elements 37, only one such closure element 37 being visible in such Figure. The closure elements 37, which are loaded during operation by tension or traction forces, are attached at the side elements 14 by screws or threaded bolts 40 so as to nest upon the bearing or contact surfaces 38. These bearing or contact surfaces 38 extend in the direction of the force which loads the same, i.e., parallel to the plane taken through the axis O of the rolls 1 and 2 and parallel to the direction of movement of the pistons 4.
In order to take-up the thrust forces which are effective along the contact or support surfaces 38 there are provided pins 41, the axis of which extends essentially through the common contact or support surface 38. During the initial assembly the closure elements 37 are attached by the screws or threaded bolts 40 or equivalent structure, whereafter there are drilled and reamed the bores for the pins 41, which extend as perpendicular as possible to the thrust forces effective during operation, i.e., parallel to the axes of the rolls 1 and 2. Thereafter there are mounted the pins 41 which preferably are attached at one of the elements or parts, the closure element 37 or the side element 14, for instance by means of a weld or a soldered connection. The pins 41 or the like may be cylindrical or have a slightly conical shape.
During operation the pins 41 transmit the occurring traction force as a shearing force over the cross-section of their entire length. During assembly following the erection work the pins 41 facilitate the attachment of the closure elements 37 since their domed cylindrical surface have a centering action during mounting of the elements or parts.
As still apparent from the showing of FIGS. 1 and 2, the rolls 1 and 2 are provided with scrapers 50 or equivalent structure. The upper scraper 50 coacting with the roll 1 is pivotably mounted in the bearing or support housings 52 which are attached to brackets 53 or the like which, in turn, are secured to end walls 54 of the side elements or parts 14. The other lower scraper 50 coacting with the roll 2 is mounted in bearing housings 52, whose brackets 53 are secured at the inner side walls of the side elements 14.
As further seen by referring to FIGS. 1 and 2, the side elements 14 are fabricated of solid material of essentially constant thickness D and have a rectangular shape with linear end surfaces 54 and 54', respectively. Such form is particularly suitable for fabrication from rolled steel material, for instance of steel plate, and by using simple means that can be obtained a particularly great strength and rigidity of the support arrangement. Most of the surface thus can be fabricated in a simple manner by flame cutting without any further post machining work. Machining work is only required at the contact or support surfaces of the bearing blocks 15 and 16, the closure elements 25 and 37 and the guide surfaces of the part or element 27. On the other hand, the brackets 53 can be attached to unworked or non-machined surfaces or surfaces which have been only crudely or roughly worked by flame or gas cutting, since the bearings of the bearing housing 52 enable inclination of the shaft of the scrapers.
Due to the particularly simple construction it is to be appreciated that the illustrated support arrangement allows for a rapid dismantling of the rolls 1 and 2. The roll 1, following removal of the closure elements 25, can be upwardly raised, the roll 2, following removal of the closure elements 37, can be laterally dismantled. Since the scrapers 50 are arranged in each case at the side of the cutouts or recesses removed from the closure elements the removal of such scrapers, during dismantling of the rolls, is not necessary.
FIG. 5 illustrates in side view a rolling device or roller mill having four rolls and which in principle corresponds to the arrangement of FIGS. 1 to 3. The parts shown in FIG. 5 correspond to those of FIGS. 1 to 3, therefore, have been generally conveniently designated with the same reference characters. Moreover, it is thought sufficient to simply consider at this point the differences between both embodiments.
Thus, in addition to the cutouts or recesses 17 and 18 there are further provided two additional cutouts or recesses 60 and 61. Provided in the cutout 61 is a bearing block or bearing means 62 which essentially is the same as the bearing block or bearing means 15, however attached by screws or threaded bolts 63 or equivalent fastening devices to a support surface 64 at a side of the cutout 61. The cutouts 18 and 61 are both conjointly covered by a single closure element 37'. This closure element 37' is secured and fixed in the same manner as the closure element 37 by the screws or threaded bolts 40 and pins 41. The bearing block 62, apart from being fixed at the surface 64, is also still fixed at the closure element 37' by a spring 24 or equivalent structure.
In the cutouts 60 of the side elements 14' of FIG. 5 there are arranged pivotal bearing blocks or bearing means 65 which are connected by pins 66 or the like with the base plates 67 which, in turn, are attached by screws or threaded bolts 68 at a side surface 70 in the cutout 60. If the roll which is mounted in the cutout 60 is a solid roll or if for instance it is a roll of the type disclosed in U.S. Pat. No. 3,802,044 devoid of its own lifting mechanism, then there can be provided between the bearing block 65 and the lowersurface of the cutout 60 a simple lifting mechanism in the form of a rubber bellows 71 or equivalent structure which can be actuated by compressed air.
It should be understood that the Figures, especially FIG. 5, only constitute schematic views, and that the illustrated bearing blocks as well as also the cutouts can be varied in different other combinations. Thus, for instance, in FIG. 5 the upper bearing block 15 can be replaced by a bearing block 16. The movable bearing block 65 can be used at a different location or can be completely omitted.
As also best seen by referring to FIG. 5, both of the side elements 14' of the rolling device or roller mill are interconnected with one another by plates 80, 81 and 82 which can be attached to the side elements, for instance by screws or threaded bolts 83 or the like. The plates serve for reinforcing the rolling device or roller mill in lateral direction as well as also as providing finger guards in order to prevent injury by the rolls to the persons servicing the equipment. Between the plates 80 and 81 there is located a gap or space 84 rendering possible the introduction of a paper web P. The same plates also can be provided for the equipment of FIGS. 1 and 2.
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 rolling device or roller mill containing controlled deflection rolls is provided with a support arrangement possessing side portions having cutouts intended to receive bearing blocks for the rolls and closed by detachable closure elements. The side elements can be formed, as by cutting, from sheet plate and are only minimumly machined. | 3 |
FIELD OF THE INVENTION
The invention relates to an electric household appliance, especially a dishwasher, comprising a door and a door lock for said door, comprising: a frame with an opening for a hook, a closing member such as a closing lever in said frame, a closing spring disposed between the closing member and a counter-bearing in said frame, said closing member being connected to a gripping device.
BACKGROUND OF THE INVENTION
Electric household appliances, especially dishwashers or an electric baking oven, pose a hazard for children which should not be underestimated. Children at play can accidentally or intentionally open the door of an electric household appliance and thereby expose themselves to a considerable risk of injury. In dishwashers this arises, for example, from pointed sharp objects such as knives since children can thereby incur cutting wounds. In baking ovens there is a considerable risk of injury as a result of the high temperatures. For this reason, mechanical devices which prevent any unintentional or undesired opening of the door of an electric household appliance are already available as child-safety features.
Known from DE 195 04 928 A1 is a door lock for a dishwasher for whose actuation an unlocking flap is mounted pivotally about a pivot axis in a handle recess and is provided with a locking stop arrangement which prevents any pivoting of the unlocking flap in a locking home position. Moulded on the pivot axis of the unlocking flap is a radially directed locking lug which engages axially in a matched stop in a bearing wall of the handle shell. A disadvantage here is that as a result of the complex structure, the child safety feature is expensive and liable to breakdown and the operating comfort for the user of the dishwasher is only low.
Known from DE 198 37 248 C2 is a door lock for the door of an electric household appliance comprising a frame with an opening for a hook, a closing member such as a closing lever, in the frame, a closing spring disposed between the closing member and a counter-bearing in the frame, said closing member being connected to a gripping device. In this case, the closing spring is tensioned in an open position of the door lock and the gripping device is pressed against a part of the frame or in the frame by the closing spring at a contact point in the open position of the door lock, thus preventing the release of the spring. The gripping device has a gripping latch into which a hook is guided on passing through the opening in the frame. The incoming hook presses on a contact surface of the gripping device and thereby causes a movement of the gripping device. The gripping device is shaped so that it loses contact with the contact point during a movement of the hook and the closing spring can thereby be released. The opening of the closed door by forces from inside or outside can only be prevented by a lock which releases the closing member during opening by means of an opening lever. This door lock disadvantageously therefore does not have a child safety feature which prevent undesired opening of the door.
SUMMARY OF THE INVENTION
It is thus the object of the present invention to provide an electric household appliance, especially a dishwasher with a door lock, having a child safety feature which allows high operating comfort to be achieved with a simple and reliable structure of the door lock.
The electric household appliance according to the invention, especially a dishwasher, comprising a door is provided with a door lock for said door, comprising a frame with an opening for a hook, a closing member such as a closing lever in said frame, a closing spring disposed between the closing member and a counter-bearing in said frame, said closing member being connected to a gripping device, wherein a pin or slide which can be moved between two positions, inhibits the movement of the closing member in a first position for activating a child safety feature and does not inhibit the movement of the closing member in a second position of the pin for deactivating the child safety feature.
In the first position where the child safety feature is activated, the movable pin is preferably inserted into a recess of the closing lever or lies at the edge of said closing lever and the movement of the closing lever is thereby positively inhibited.
Advantageously disposed on the movable pin is a locking head which in the first position of the pin with the child safety feature activated, is inserted in a recess of a portion of the door, for example, a side wall of the frame or a control panel so that as a result of a positive connection between the locking head and the boundary of the recess, the forces applied to the pin are predominantly transferred to the boundary of the recess.
In a further embodiment, in the second position with the 20 child safety feature deactivated, the movable pin is located outside the recess or the edge of the closing lever and thereby the movement of the closing member is not inhibited.
More appropriately, the pin can preferably be moved in a direction of movement perpendicular to the direction of movement of the closing member and the pin has a conical 25 shape with increasing diameter beginning at the free end of the pin so that when very high forces act on the closing member, as a result of a small angle of inclination, i.e. 20° between the circumferential surface of the pin and the bearing surface on the pin, e.g. the boundary surface of the recess, the pin can be moved into the second position due to resulting normal forces in the pin.
In another embodiment, the closing spring is tensioned in an open position of the door lock, the gripping device is pressed against a part of the frame or in the frame by the closing spring at a contact point in the open position of the door lock, thus preventing the release of the spring, the gripping device has a gripping latch into which a hook is guided on passing through the opening in the frame and has a contact surface onto which the incoming hook presses, thereby causing a movement of the gripping device and the gripping device is shaped so that it loses contact with the contact point during a movement of the hook and the closing spring can thereby be released.
Advantageously, the pin is fixed to a pivoted shaft by means of a pivoted lever so that the pin can execute a rotary movement from the first position into the second position and conversely.
More appropriately, by means of a restoring lever connected to the pivoted shaft and a spring, a restoring moment can be applied to the pivoted shaft so that the pin is pressed into the first position to activate the child safety feature.
In an additional embodiment, a preferably rectangular plate made of plastic with a locating lug and a limiting lug is formed on an adjusting lever connected to the pivoted shaft wherein as a result of the thickness of the plate, said plate 20 can be elastically deformed under application of small forces.
Advantageously beginning with the free end, the adjusting lever projects partly over a slot-shaped recess in a gripping shell into a handle of the door such that as a result of a movement of the adjusting lever the pin can be moved from the first position into the second to position to activate and deactivate the child safety features, wherein the direction of movement of the adjusting lever in the handle is preferably lateral and horizontal.
More appropriately, the adjusting lever can be detachably fixed in the second position of the pin for continuous deactivation of the child safety feature, whereby the adjusting lever rests with a limiting strip on a flat area, e.g. of the panel dish and the movement of the adjusting lever to the first position is blocked by the locating lug on the limiting strip.
In an additional embodiment, to activate the child safety feature, the locating lug can be raised over the limiting strip through a small recess in the gripping shell of the handle using a pointed object, so that as a result of the force of the spring, the adjusting lever can be moved into the first position and for continuous deactivation of the child safety feature, the locating lug can be raised over the limiting strip using a pointed object whilst simultaneously activating the adjusting lever in the handle.
Advantageously, the pin is arranged on an actuating slider in a slider housing and by means of a translational movement of the actuating slider in the slider housing, the pin can be moved between the first position and the second position and conversely, preferably between two stop points.
In another embodiment, an actuating lever 8 is formed on the actuating slider which projects via a slot in the gripping shell of the handle therein and the actuating slider can thereby be moved from the handle with the actuating lever between the first and second position, wherein the actuating lever can be pressed into the first position by a spring.
More appropriately, a locating lug is formed on the actuating slider which in the second position of the actuating slider engages in a recess of the slider housing and preferably either the displacement of the actuating slider from the second position into the first position can be executed only by the actuating lever or the locating lug must be additionally pressed in via a recess on the gripping shell of the handle using a sharp object.
Advantageously, the movement of the pin from the first to the second position and conversely to activate and deactivate the child safety feature is adjustable from the top of the door using an actuating element.
In another embodiment, the actuating element, e.g. a lever, a cup-shaped disk or a part which can be actuated using a screwdriver is arranged fixedly or removably on the top.
In a further embodiment, the actuating element is connected to an actuating shaft on which a cam is formed and using the cam on the actuating shaft the pivoted lever with pin can be moved from the first into the second position and conversely.
More appropriately, the movement of the pin from the first to the second position and conversely to activate and deactivate the child safety feature can be executed by a preferably electric actuator, e.g. a wax expansion element, a bimetal part, an electromagnet or an inserted/withdrawn memory part.
In an additional embodiment, the actuator can be controlled using an electric, electronic or mechanical control using a specific control logic wherein, for example, the child safety feature is continuously activated, only activated during operation or a certain button or button combination must be pressed to deactivate the child safety feature.
The actuator can preferably be controlled by remote control, preferably via a radio signal or via the internet. As a result, the operator need not stay at the household appliance to actuate the child safety feature but he can conveniently execute it from any location in the vicinity of the household appliance. For household appliances connected to the interne, it can even be actuated from any computer with interne access.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention is explained in detail hereinafter with reference to the exemplary embodiment shown in the drawings 8 25 .
In the figures:
FIG. 1 is a section through a door lock from the prior art,
FIG. 2 is a section through a door lock according to the invention in the open position,
FIG. 3 is a section through a door lock according to the invention in the closed position,
FIG. 4 is a plan view of a locking device according to the invention,
FIG. 5 is a plan view of a plate according to the invention as part of the locking device,
FIG. 6 is a plan view of an adjusting lever according to the invention as part of the locking device,
FIG. 7 is a side view of the pivoted lever with pin according to the invention,
FIG. 8 is a perspective view of a gripping shell from below for a handle according to the invention,
FIG. 9 is a perspective view of a gripping shell from above for a handle according to the invention,
FIG. 10 is a perspective view of an actuating slider 15 according to the invention in a slider housing,
FIG. 11 is a perspective view of an actuating slider according to the invention in a slider housing,
FIG. 12 is a perspective view of an actuating slider according to the invention,
FIG. 13 is a perspective view of a door of a dishwasher according to the invention with an actuating element according to the invention at the top,
FIG. 14 is a perspective view of a door lock according to the invention with actuating shaft and actuating element, and
FIG. 15 is a cross-section through the actuating shaft with cam and pivoted lever according to the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The operating mode of the door lock 101 is first explained hereinafter disregarding the child safety feature with reference to FIGS. 1 to 3 . The child safety feature according to the invention is also shown in FIGS. 2 and 3 . FIG. 1 exclusively shows a door lock from the prior art without child safety feature. The door lock in FIG. 1 is a door lock known from DE 198 27 248 C2.
A closing lever 12 pivotable about an axis 14 is accommodated in a frame 10 . In the open position of the door lock 101 shown in FIG. 2 a closing spring 16 is tensioned between the closing lever 12 and a counter-bearing 18 , thus pressing the closing lever 12 in the counterclockwise direction.
A gripping device 20 is mounted rotatably about an axis 22 on the closing lever 12 . The axis 22 of the gripping device 20 is located on the closing lever 12 between the area on which the closing spring 16 acts and the axis 14 of the closing lever 12 . The gripping device 20 has a circumferential line which forms a pitch circle about the axis of rotation. As a result of the closing spring 16 , the gripping device 20 is pressed against a stop face 28 on a stop member 26 of the frame 10 .
The circumferential line of the gripping device 20 leads to a slide edge which runs radially inwards at an angle of 90° from a tangent of the circumferential line of the gripping device 20 . A stop edge 32 of the gripping device 20 is located perpendicularly to the slide edge 30 .
The gripping device 20 is located in a recess of the closing lever 12 . In the exemplary embodiment shown the closing lever 12 is tensioned counterclockwise by two closing springs 16 (only one is shown in FIGS. 1 to 3 ). According to the diagram in FIGS. 2 and 3 , therefore closing spring 16 is located in the viewing direction of the observed in front of the gripping device 20 and one closing spring is located behind the gripping device 20 .
A gripping latch 34 is embodied as an eccentric indentation in the circumference of the gripping device. In the open position of the door lock 101 , its opening points towards an opening 36 in a side 40 of the frame 10 facing a hook 38 . When the hook 38 is guided through the opening 36 on closing the door 95 , it presses on a contact surface 42 of the gripping latch 34 and cause the gripping device 20 to turn counterclockwise. As a result of the turning, the slide edge 30 reaches a corner 44 of the frame 10 . The closing spring 16 can be released, the closing lever 12 turns about the axis 14 and the gripping device 20 slides with the slide edge 30 along a surface 46 of the frame 10 , whereby the slide edge 30 is pressed against the surface 46 of the frame 10 by the torsion spring 24 . The front portion 49 of the hook 38 has contact with a second contact surface 48 of the gripping latch 34 and is entrained by the gripping latch 34 . In this case, the door 95 is pressed against the seal. At the same time as these movements, a door switch 50 which is actuated by means of the closing lever 12 is closed, the torsion spring 24 is tensioned and an opening lever 52 is moved by the closing lever 12 acting on an arm 54 of the opening lever 52 . This results in the closed position of the lock 101 shown in FIG. 3 .
When the lock 101 is opened, the opening lever 52 is moved clockwise, and the arm 54 of the opening lever 52 presses together the closing lever 12 clockwise and the closing spring 16 . In this case, the gripping device 20 again slides with the slide edge 30 along the surface 46 of the frame 10 ( FIG. 3 to the right), 15 until the gripping device 20 is returned by the torsion spring 24 (possibly in cooperation with a seal pressing the door away from the housing of the appliance) into the position corresponding to the open position of the door lock, where the hook 38 is released and the door opens. At the same time as opening the lock, the door switch 50 is actuated by the closing lever 12 and is opened.
The tolerance of the hook 38 in the closed position is determined by the length of the slide edge 30 . The front portion 49 of the hook 38 cannot snap out of the gripping latch 34 as long as the gripping device 20 does not turn, i.e. as long as the closing lever 12 only turns about its axis 14 .
Shown in FIG. 1 as prior art is the door lock 101 with an additional lock 60 compared with FIGS. 2 and 3 , apart from the child safety feature according to the invention, which prevents opening of the closed door by forces from inside or outside. The forces acting on the door can, for example, be a steam impact from inside or a pulling open from outside. The lock 60 can, for example, be embodied as the edge on the frame 30 or as an additional part. The lock 60 prevents turning of the closing member 12 in the opening direction before the gripping device 20 is released over the slide edge 30 on the corner 44 . During opening by means of the opening lever 52 , first the closing member 12 is released and then the door 35 is opened. Disadvantageously each opening with the opening lever 52 effects a release of the closing member 12 so that children can lift the lock 60 . The child safety feature according to the invention can naturally also be executed on a door lock 101 with an additional lock 60 according to FIG. 1 .
In order to eliminate undesired opening of the appliance door 95 , e.g. by children as a child safety feature, according to the invention a pin 70 or a slider (not shown) can be inserted in a recess 71 in the closing lever 12 . The pin 70 can rest on a wall of the closing lever 12 (not shown) to block the closing lever 12 . The pin 70 in the recess 71 positively blocks the rotary movement of the closing lever 12 about the axis 14 in the closure position ( FIG. 2 ). As a result, the gripping device 20 does not release the hook 38 and the door cannot be opened. In the open position the pin 70 is located outside the closing lever 12 , for example, it lies on the wall of the closing lever 12 . The frame 10 preferably has a side wall 72 in the area of the recess 71 of the closing lever 12 with a recess 73 . In the closed position the recess 73 in the side wall 72 of the frame 10 and the recess 71 of the closing lever are in alignment with one another. The side wall 72 is located in front of the closing lever 12 in the view in FIGS. 2 and 3 .
Viewed from the plane of the drawing from FIGS. 2 and 3 , a locking head 74 is constructed on the pin 70 which, depending on the type of plug connection, is inserted as an exact fit with little play into the recess 73 in the closed position. By this means the forces applied to the pin 70 by the recess 71 on the closing lever 12 are transferred via the locking to head 74 to the recess 73 of the frame 10 .
As a result of the short distance between the locking lever 12 and the side wall 72 of the frame 10 , predominantly only transverse forces thereby occur at the pin 70 and at the locking head 74 and only a small bending moment. High stressing of the material can thereby be avoided even when large forces act on the pin 70 and the movable mounting for the pin 70 can be executed simply and therefore inexpensively because only very small forces act on this mounting. Such a recess 73 for positive retaining of the locking head 74 and therefore the pin 70 can also be constructed in a wall which is not part of the frame 10 , e.g. in the panel housing, where this wall must be located at the shortest possible distance from the closing lever 12 .
Step-shaped gradations are advantageously formed on the locking head 74 which run perpendicular to the plane of the drawing in the alignment from FIGS. 1 and 2 and therefore in the direction of the longitudinal axis of the pin 70 ( FIG. 7 ). Thus, in the closed position when the closing lever 12 is blocked, the locking head 74 rests with one gradation, preferably the last gradation, on the side wall 72 of the frame 10 on the recess 73 (not shown). The insertion of the pin 70 into the recess 71 of the closing lever 12 can thereby be limited in the closed position.
The pin 70 is preferably shaped as conical with decreasing diameter towards the end of the pin 70 ( FIG. 7 ). As a result, in the event of a fault with the lock for example, the door can still be opened with very much increased force in the closed position with the child safety feature activated because as a result of the conical shape of the pin 70 , the casing surface of the pin 70 rests at a very small angle of inclination, e.g. 20° on the recess of the closing lever 12 . As a result, a force applied via a panel handle of the door on the recess 71 and the pin 70 brings about a normal force in the pin 70 , in addition to a transverse force, which presses said pin out from the recess 71 . It is thereby advantageously possible to open the door in an emergency, e.g. in the event of a defect in the device for the child safety feature, e.g. the locking device 69 .
There are various possibilities for implementing the mounting for the movement of the pin 70 :
In a first embodiment ( FIG. 1 , 2 , 3 , 4 , 5 , 6 , 7 ) the pin 70 with locking head 74 is affixed to a pivoted lever 75 , the axis of the pin 70 preferably being perpendicular to the axis of the pivoted lever 75 . The pivoted lever 75 opens into a pivoted shaft 76 of the locking device 69 which preferably consists of plastic. In this case, the axis of the pivoted lever 75 is also preferably perpendicular to the axis of the pivoted shaft 76 . The pivoted lever 75 is preferably executed as substantially rectangular in cross-section so that it is better able to absorb a bending moment, the longitudinal side being substantially longer than the broad side, e.g. by a factor of four. The longitudinal sides are parallel to the axis of the pin 70 . The pin 70 can thereby absorb large bending moments. The pivoted shaft 76 is rotatably mounted by a simple friction bearing 77 at the upper end 78 and the lower end 79 ( FIGS. 2 and 3 ). Located near the lower end 79 of the pivoted shaft 76 is another restoring lever 80 with a projection 84 . Located on the upper side of the projection is a wire of a torsion spring 81 whereby a force is continuously applied to the restoring lever 80 ( FIG. 4 ). This produces a continuous restoring torque via the restoring lever 80 in the pivoted shaft 76 , which is directed counterclockwise when viewed in the direction of the axis of the pivoted shaft 76 form the lower end 79 to the upper end 78 . The pin 70 is thereby pressed continuously in the direction of the recess 71 of the closing lever 12 . In each closed position the pin 70 is therefore pressed into the recess 71 of the closing lever 12 . The child safety feature is thus activated.
A mechanism which prevents the pin 70 from being inserted into the recess 71 of the closing lever 12 is required to deactivate the child safety feature. For this purpose another adjusting lever 82 is arranged in the pivoted shaft 76 between the pivoted lever 75 and the restoring lever 80 .
The axis of the adjusting lever 82 , like that of the levers 75 , 80 , is perpendicular to the axis of the pivoted shaft 76 . The adjusting lever 82 is not executed as straight like the other levers 75 , 80 but has an offset 83 approximately at the centre, directed towards the lower end 79 of the pivoted shaft ( FIG. 4 ). The axes of the two halves of the adjusting lever 82 before and after the offset 83 are parallel, i.e. are perpendicular on the axis of the pivoted shaft 76 . A rectangular plate 86 ( FIGS. 4 , 5 , 6 ) 18 is constructed on the second half of the adjusting lever 82 , i.e., between the free end 85 of the adjusting lever 82 and the offset 83 , in the vicinity of the offset 83 . The plane of the plate 86 is perpendicular to the axis of the adjusting lever 82 ( FIGS. 1 , 2 and 6 ). The longitudinal sides of the rectangular plate 86 are approximately perpendicular to the axis of the adjusting lever 82 , i.e., the plate 86 is directed approximately perpendicularly downwards in the plane of the drawing in FIGS. 2 , 3 and 4 . A locating lug 87 and a limiting lug 88 are constructed on the plate 86 as an extension of the plate 86 . The plate 86 and therefore the lugs 87 , 88 are preferably slightly wedge-shaped, i.e. with increasing thickness in the direction of the pin 70 . The thickness of the plate 86 is relatively small, e.g. between 1 and 2 mm, so that as a result of using plastic the plate 86 is very flexible towards small forces. Furthermore, a wedge 89 ( FIG. 6 ) is located on the second half of the adjusting lever 82 with increasing thickness in the direction of the pin 70 .
The adjusting lever 82 , preferably in an easily identifiable colour, projects in the area of the free end 85 approximately as far as the recess 93 in the handle to actuate the door on the panel shell. At the same time, a slot-shaped, horizontal recess is provided in the gripping shell 93 of the handle so that the adjusting lever 82 can be moved from outside in the handle (not shown). Advantageously, the adjusting lever 82 can only be displaced laterally in the horizontal direction in the handle so that any unintentional movement of the adjusting lever 82 is eliminated because this must be specifically moved sidewards in the handle. A child is unable to do this. In different panel designs the adjusting lever must be located at different height positions. For this purpose only one adjusting lever 82 with a different offset 83 needs to be selected with an otherwise identical locking device 69 . The child safety feature can thereby be activated and deactivated because the pivoted shaft 76 is also turned by the movement of the adjusting lever 82 and thus the pin 70 can be moved into or out of the recess 71 of the closing lever 12 . In this case, before every opening of the door the adjusting lever 82 must be displaced laterally in the horizontal direction against the spring force of the spring 81 towards the lateral end of the handle. If this does not take place, e.g. if a child is does not known how to do this, the door cannot be opened because the pin 70 remains in the recess 71 of the closing lever 12 and the movement of the closing lever 12 is blocked by the fixing of the locking head 74 in the recess 73 of the side wall of the frame 10 .
In a preferred embodiment the adjusting lever 82 can be fixed in the state where the to child safety feature is deactivated, i.e. it is not necessary for the adjusting lever 82 to move in the handle to open the door. In this case, a small round recess (not shown) is additionally located in the handle. The plate 86 which is located on the adjusting lever 82 then rests on a flat area in the panel shell, where a limiting strip is provided on a flat area (not shown) between the locating lug 87 and the limiting lug 88 in the deactivated state of the child safety feature. This prevents movement of the adjusting lever 82 , especially the return movement into the first position in the activated state of the child safety feature is blocked by the locating lug 87 on the limiting strip. The adjusting lever 82 can thus not be moved and as a result of the position of the adjusting lever 82 , the pin 70 is outside the recess 71 of the closing lever 12 so that the door lock cannot be blocked. As a result of the spring force of the spring 81 , the locating lug 87 rests on the limiting strip oh the flat area (not shown). To activate the child safety feature, i.e. to allow a movement of the pin 70 into the recess 71 of the closing lever 12 , the adjusting lever 82 must be released from this position again. For this purpose, a pointed object, e.g. a ball-point pen should be inserted into the small round recess on the handle. The locating lug 87 is thereby raised over the limiting strip, which can advantageously be achieved with small forces because of the resilient properties of the plate 86 . The adjusting lever 82 thus folds back into the position of the activated child safety feature on account of the restoring force of the spring 81 . To deactivate the child safety feature, the adjusting lever 82 must be displaced horizontally laterally in the handle and at the same time, a pointed object must be inserted into the small round recess so that the locating lug 87 can be raised over the limiting strip on the flat area (not shown) and the desired locking of the adjusting lever 82 with the locating lug 87 on the limiting strip against the restoring force of the spring 81 can be achieved. It is especially advantageous here if both a movement of the adjusting lever 82 and the insertion of a pointed object into the small recess is required simultaneously so that any unintentional deactivation of the child safety feature is almost eliminated.
In a second embodiment for mounting the movement of the pin 70 ( FIGS. 8 , 9 , 10 , 11 , 12 ), said pin is disposed on an actuating slider 90 . The actuating slider 90 is located in a slider housing 91 in which it executes a translational movement between two stop points. For movement of the actuating slider 90 an actuating lever 92 is formed thereon, which projects into the gripping shell 93 of the handle via a slit therein ( FIG. 8 ). The actuating slider 90 can thereby be moved. Also located in the slider housing 91 is a spring (not shown) which presses to the actuating slider 90 in the activated state of the child safety feature, i.e. so that in the closed position of the lock the pin 70 is pressed into the recess 71 of the closing lever 12 . To open the door on the dishwasher the actuating slider 90 must be pressed using the actuating lever 92 against the force of the spring in the deactivated state of the child safety feature i.e. so that in the closed position of the lock the pin 70 does not project into the recess 71 of the closing lever 12 . In a preferred embodiment a locating lug 94 is formed on the actuating slider 90 ( FIG. 8 , 10 , 12 ). In the deactivated state this engages in a recess on the slider housing 91 whereby the actuating slider 90 is fixed in the deactivated state. As a result, the actuating lever 92 must be displaced in the handle to open the door. In addition to this, the locating lug 94 can be constructed on the actuating slider 90 such that to deactivate the child safety feature it is not merely sufficient to move the actuating lever into the corresponding position but in addition the locating lug 94 must be pressed with a pointed object. For this purpose, a suitably aligned recess is formed on the gripping shell 93 of the handle ( FIG. 8 ). In a dishwasher, the slider housing 91 is preferably located above the gripping shell 93 for the handle.
In a third mechanical embodiment of the invention, especially for fully integrable dishwashers and dishwashers with clip handles which do not have a handle, the child safety feature can be activated and deactivated from the top 96 of the door 95 by means of an actuating element 97 ( FIG. 13 ). For this purpose the actuating element 97 is continuously or temporarily connected at the top 96 to an actuating shaft 98 with a removable actuating element 110 ( FIG. 14 ). Located on the actuating element 98 is a cam 99 which raises the pivoted lever 75 during a rotary movement of the actuating shaft 98 ( FIG. 15 ) and thereby deactivates the child safety feature. The actuating shaft 98 is preferably only rotatable within a certain angular range e.g. 30° as a result of corresponding additional protrusions on the actuating shaft 98 (not shown). In addition to this mechanism, other devices for activating and deactivating the child safety feature are also possible.
For example, the pivoted shaft 76 can be extended as far as the top 96 with the result that an additional actuating shaft 98 is not required (not shown).
The removable actuating element 110 can be variously executed. For example, it can preferably be coupled to a removable lever 97 according to FIG. 13 or it could take the form of to a disk 110 according to FIG. 14 . A removable lever has the advantage that this is not visible when removed. The actuating element 97 can preferably be actuated when the door 95 is closed e.g. it projects lightly over the gap between the top 96 of the door 95 and the lower edge of the worktop of the door (not shown). It is also possible to have an actuating element 97 which is only actuated using a screwdriver, for example, when the door 95 is closed and/or open.
In another fourth embodiment (not shown) the pivoted lever 75 can be operated by means of a tension cable with restoring spring from the clip handle 100 of the door 95 .
In a further embodiment the movement of the pin 70 is accomplished using a preferably electric actuator. For example, this can be a wax expansion element, a bimetal part, an electromagnet or an inserted or withdrawn memory part. The child safety feature is activated and deactivated by means of a mechanical, electrical or electronic appliance control. The pin 70 can also be part of the actuator.
Various possibilities exist for the control logic: for example, the child safety feature can be continuously activated or only during operation of the household appliance. The child safety feature can also deactivated by programming, i.e. a special button or a special combination of buttons must be pressed to open the door 95 . This embodiment with an actuator can be used in all appliance designs, e.g. a free-standing appliance, a build-under appliance, an integrated build-under appliance and a fully integrated build-under appliance. It is also possible for the activation and deactivation to be accomplished by remote control, preferably via a radio signal. The control system has a corresponding receiving portion for this purpose. Remote control can be secured against unauthorised actuation by means of a coding, e.g. a password. For household appliances connected to the Internet, the activation or deactivation can be accomplished by the internet.
The present invention provides a simple and inexpensive device for a child safety feature in household appliances with a door, especially a dishwasher, with an emergency unlocking function. As a result of the different embodiments, an optimal adaptation to different design variants can be made both for a mechanical actuation and for actuation using an actuator. | The aim of the invention is to provide an electric household appliance, especially a dishwasher, comprising a child-proof lock which has a simple and reliable design and is easy to operate. According to the invention, a means for selectively blocking or slide which can be moved between two positions blocks, in a first position, the movement of the locking member, thereby activating the child-safety feature, and in a second position of the means for selectively blocking, does not block the movement of the locking member, thereby deactivating the child-safety feature. | 4 |
BACKGROUND OF THE INVENTION
The present invention relates broadly to an electromagnetic wave transmission device and in particular to a waveguide launcher apparatus for coupling a coaxial transmission line to a waveguide array antenna element.
In coupling a hollow waveguide to a coaxial transmission line, it is desirable to convert the waveform from one most suitable for transmission in a coaxial line to a form suitable for propagation in a waveguide. Therefore, the wave in the coaxial line requires that it be converted to a form compatable with the geometry of the waveguide. In the prior art, many techniques for accomplishing this purpose have been proposed and built, and usually have accomplished their basic purpose, but most of them have involved undesirable bulk or complicated devices which have resulted in inefficient transmission. The present invention provides a waveguide launcher apparatus which overcomes the difficulties encountered in the past systems and provides an extremely simple and compact system for coupling a coaxial transmission line to a waveguide array antenna element.
SUMMARY OF THE INVENTION
The present invention utilizes an L-shaped coax waveguide launcher assembly for use in a rectangular waveguide. The waveguide launcher assembly utilizes its short depth to achieve a match between the coax connector and free space. This desired match is achieved by configuring the coax to waveguide launcher assembly as a matching element and as an adapter between the coax and waveguide sections.
It is one object of the invention, therefore, to provide an improved coax to waveguide launcher apparatus providing a transition between a coaxial transmission line and a waveguide which permits the longitudinal axis of the coaxial line to be aligned with the propagation axis of the waveguide.
It is another object of the invention to provide an improved coax to waveguide launcher apparatus utilizing simplified and compact construction.
It is still another object of the invention to provide an improved coax to waveguide launcher apparatus having short depth to achieve a desired match between the coax connector and free space.
These and other advantages, features and objects of the invention will become more apparent from the following description taken in connection with the illustrative embodiment in the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a plane view of the waveguide launcher apparatus in accordance with the present invention,
FIG. 1a is a perspective view of the waveguide launcher element of FIG. 1, and
FIG. 2 is a sectional view of the waveguide launcher element positioned in a rectangular waveguide.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to FIG. 1, there is shown the waveguide launcher element 10 comprising two rectangular members which are joined at one end respectively to have a substantially L-shape. For example purposes only, the waveguide launcher element 10 will be described with respect to typical dimensions which provide the functions herein stated. However, it must be clearly understood that there is no intention to limit the scope of the present invention to these particular dimensions. The waveguide launcher element 10 has a drilled tapped hole at the end of the short member to facilitate the mounting of the waveguide launcher element within a conventional waveguide assembly. This drilled hole is 0.38 inches deep and is tapped to accept a 6-32 stainless steel screw. The long member of the waveguide launcher element has a hole drilled into the end therein to mate with the center pin of a coaxial transmission line connector. This hole is 0.125 inches in diameter and is 0.38 inches deep. The long member of the waveguide element which is shown in FIG. 1 may have a length of 2.485 inches overall. The short member of the waveguide L assembly has a length of 0.675 inches overall. The waveguide element has a square shape and each side is 0.250 inches long. The long member of the waveguide launcher element has its free end tapered and beveled to approximately 45° so as to have a 0.156 diameter circle at the end thereof. The drilled tapped hole in the short member is located 2.350 inches from the long end of the longitudinal member. The material from which the waveguide launcher element is fashioned in CDA copper alloy No. 863 (AMS 4862).
Turning now to FIG. 2, there is shown in section a conventional rectangular waveguide assembly 12 containing the waveguide element 10 of FIG. 1 therein. There is shown beryllium oxide (BeO) window 14 at one end of the waveguide assembly. The BeO window 14 is fashioned from material which connects 99.5 percent beryllium oxide and has a thickness of 0.99 ± 0.003. The flexual strength of the BeO window is 32,000 psi minimum and its compressive strength is 200,000 psi minimum. The average dielectric constant K o of the BeO window is 6.55 at 25° centigrade and at 1.3 Ghz. The BeO window is rectangular in shape and has the dimensions of 3.720 by 1.950. A suitable sealing compound is utilized all around the window to maintain it in its position within the rectangular waveguide and to provide a seal therefor.
There is shown at the opposite end of the waveguide assembly a coaxial connector 16 which is a UG58A/U connector. The coaxial connector 16 is mounted on a guide 18 which is attached to the waveguide. An O ring is mounted around the guide to provide a positive seal between the guide 18 assembly and the waveguide. The waveguide launcher element is shown mounted within the waveguide assembly with its longitudinal axis aligned with the center pin of the coaxial connector. The waveguide launcher element has one end soldered to the pin of the coaxial connector. The other end of the waveguide launcher element is fastened to the waveguide wall by a stainless steel hexagonal socket cap screw.
It may be seen from FIG. 2 that an antenna element is formed which comprises a rectangular waveguide main body, a BeO window, and a coax to waveguide launcher assembly. It may also be seen from FIG. 2 that the waveguide launcher element has a unique feature of its short depth intrusion into the waveguide main body to provide the desired match between the coax connector and free space. This match is achieved by configuring the coax to waveguide launcher element as a matching element as well as an adapter between the coaxial transmission line connector and waveguide section. The window and inductive iris combination at the aperture is tuned for match at midband and presents a significant mismatch at the band edges. The coax to waveguide launcher element is configured such that it is tuned for a match at midband and that the combination of the aperture and the launcher element is also matched at the band edges. This particular configuration of the waveguide launcher apparatus allows a match to be achieved over the desired bandwidth, in the present case 10 percent about the center frequency.
The waveguide launcher element is designed to operate in the L band with a band width of ± 5 percent. The launcher element dimensions are directly scaled in proportion to the wavelength of the center frequency of operation. Therefore, if the center frequency is doubled, the launcher element dimensions are halved in order to maintain the desired match.
Although the invention has been described with reference to a particular embodiment, it will be understood to those skilled in the art that the invention is capable of a variety of alternative embodiments within the spirit and scope of the appended claims. | A waveguide launcher apparatus for coupling a coaxial transmission line to a waveguide array antenna element. The waveguide launcher apparatus utilizes its short depth to achieve the desired match between the coaxial connector and free space. The launcher apparatus has an L shape which performs as a matching element and as an adaptor between the coax transmission line and wave guide sections. | 7 |
TECHNICAL FIELD
The present invention relates to photoconversion devices such as photovoltaic cells, photodetectors and light sources.
BACKGROUND OF INVENTION
Light absorption plays a central role in optical detectors and photovoltaics. Inspired by nature, two different routes have been investigated to achieve perfect absorption. A first one consists in relying on diffusion in disordered lossy surfaces (e.g., black silver and carbon). Engineered materials have been synthesized following this solution to produce extraordinary broadband light absorption (e.g., dense arrays of carbon nanotubes). A second approach consists in using ordered periodic structures, as found in some nocturnal insects, where they produce the moth eye effect. This alternative has been pioneered by experimental and theoretical work showing total light absorption (TLA) in the visible using metallic gratings. In this context, the Salisbury screen (U.S. Pat. No. 2,599,944 B1), consisting of a thin absorbing layer placed above a reflecting surface, has been known to produce TLA, and it can be integrated in thin structures using magnetic-mirror metamaterials. Similar phenomena have been reported at infrared (IR) and microwave (Y. P. Bliokh, J. Felsteiner, and Y. Z. Slutsker, Phys. Rev. Lett. 95, 165003, 2005; N. I. Landy, S. Sajuyigbe, J. J. Mock, D. R. Smith, and W. J. Padilla, Phys. Rev. Lett. 100, 207402, 2008) frequencies, including omnidirectional TLA, which has been realized by using periodic surfaces supporting localized plasmon excitations. However, due to the specific material properties, none of these technologies have enabled conversion from absorbed light into electrical signals, or have been very inefficient as such. Additionally, these devices did not exhibit in-situ tunability of the absorption spectrum, neither emission frequencies in the infrared or THz range.
SUMMARY OF THE INVENTION
The present invention relates to photoconversion devices such as photovoltaic cells, photodetectors and light sources. In particular, the invention provides devices in which higher light absorption, or more efficient light emission can take place thanks to a single or multi-layer sheet of patterned and doped graphene. In addition, the devices of the invention also provide optimum thermal emission occurring at specific wavelengths that are selected by means of applied electric fields. And finally, it provides devices that utilize the infrared part of the solar spectrum to optimize conversion into electrical signals for improved solar cells.
In particular, the present invention solves the problems of the prior art previously commented by using graphene plasmons in an absorbing active layer of a photoconversion device.
The general working principle of the graphene plasmons in the device is as follows: graphene plasmons are collective excitations of valence electrons in graphene, a one-atom-thick layer of carbon. When the graphene is structured, the frequency of these plasmons can be customized to the desired range from the infrared to the THz and beyond. Graphene plasmons occur only if the graphene is doped with an excess of electrons or holes, otherwise these plasmons cease to exist (although there exists another set of plasmons at higher energy in the visible and ultraviolet that are less sensitive to external control, that are not further considered in this document, and that are spectrally separated from the ones we are concerned with here, which emerge in the infrared to THz and beyond). Besides, the frequency of these low-energy plasmons can be directly controlled by adjusting the density of charge carriers produced by the noted doping. In practice, doping of graphene has been performed via electrostatic gating, that is, by placing electrodes close or in contact to the graphene, so that the carbon layer has to redistribute its charges in order to screen the resulting electrostatic potentials. This means that the plasmons in this material have frequencies that can be changed at will by playing with the potential applied to the mentioned electrodes.
Using the ability of controlling the optical response of graphene, as well as the frequency and even the mere existence of its trapped optical modes, three different sets of devices are provided, for light detection (spectral photodetectors), for light emission (tunable sources), and for conversion of light into electricity (solar cells). The underlying principle of operation in all three devices is the strong coupling of light with plasmons in graphene (collective oscillations of conduction electrons). The frequency of these plasmons depends on the level of charging (i.e., doping), which is varied as specified above.
For spectral photodetectors, the present invention provides devices comprising patterned graphene that can absorb up to 100% of light at specified light wavelengths. These light wavelengths coincide with those needed to excite the plasmons (but notice that the plasmon wavelengths are reduced by a large factor with respect to the light wavelengths), because the absorption mechanism is mediated by the plasmons. Light is thus preferentially absorbed at the resonant light wavelength (i.e., the one needed to excite a plasmon), and therefore, the amount of absorbed light energy depends on the light intensity at that wavelength incident on the device. This energy is converted into heat, which produces a thermoelectric effect. The thermoelectric signal is then read, and its intensity reveals the intensity of light at the selected incident wavelength. This wavelength is then scanned over the desired range by electrostatic tuning (see above), which allows us to construct a spectrum. We thus have a spectral photodetector capable of resolving spectra of the incident light. The detector has a size of only a few microns.
For light sources, we use a similar device in which heating is produced by a heating element inside it. The graphene temperature is raised by several hundred degrees above room temperature, which causes thermal emission. The emission at a certain wavelength is proportional to the absorption at the same wavelength because of the detailed balance principle, which in this case is called Kirchhoff's law. Thus, light is preferentially emitted at the plasmon wavelength, which is tuned electrostatically. This results in a device capable of emitted light with a dominant wavelength component that can be tuned over a certain spectral range.
These principles for photodetectors and sources are general and can be applied to a wide range of spectral domains, from the infrared to the THz and beyond. However, graphene is ideally suited to cover the infrared and THz regions.
For light-to-electricity conversion, we rely on plasmons as well. Light is absorbed at the graphene to excite plasmons. Plasmons decay into electrons and holes. Junctions between the graphene and p/n semiconductors mediate the separation of electrons and holes in a way similar to what is done in conventional photovoltaic solar cells. Graphene can take care of converting the infrared part of the spectrum, for which conventional semiconductor technology is not very efficient. A battery of graphene convertors is provided, so that each convertor is specialized in a narrow spectral domain. Light is previously separated by a grating or prism, so that its convertor receives light of a wavelength at which it is most efficient.
BRIEF DESCRIPTION OF THE FIGURES
To complete the description and in order to provide for a better understanding of the invention, a set of drawings is provided.
FIG. 1A shows calculated extinction cross-sections for graphene nanodisks.
FIG. 1B shows calculated extinction cross-sections for graphene nanoribbons.
FIG. 2A shows a scheme of a periodic array of graphene disks placed at the interface between two different dielectrics.
FIGS. 2B and 2C show absorption spectra calculated for arrays of graphene disks and different parameters of the angle of incidence, incident light polarization, and dielectric constants of the two media surrounding the graphene.
FIGS. 2D and 2E show calculated absorption spectra for periodic arrays of graphene sitting on a dielectric layer on top of a gold substrate.
FIG. 3A shows a possible implementation of arrays of graphene nanoribbons to produce tunable absorption at the desired wavelengths via electrostatic doping.
FIG. 3B shows an alternative embodiment in which graphene nanoribbons are on top of a back gate separated by an insulating layer.
FIG. 3C shows another embodiment in which the graphene pattern is non-uniform along the device.
FIG. 3D shows another embodiment in which multiple layers of graphene patterns are stacked and on-uniform in the vertical direction the device.
FIG. 3E shows yet another embodiment in which the graphene shows a patterned structure as a result of a patterned local gate on top.
FIG. 3F shows a similar embodiment as in 3D with a patterned substrate.
FIG. 4 shows a spectral photodetector device, in accordance with a further embodiment.
FIG. 5 shows a tunable light source device, comprising a patterned graphene layer and a heating element.
FIG. 6 shows a graphene-based photovoltaic element, in which light incident at a selected wavelength is converted into electricity.
FIG. 7 shows a graphene-based photovoltaic device, with a wide range of wavelengths covering the desired part of the solar spectrum being absorbed at elements positioned in parallel.
FIG. 8 shows a graphene-based photovoltaic device, with a wide range of wavelengths covering the desired part of the solar spectrum being absorbed at elements positioned vertically in a stack.
DETAILED DESCRIPTION OF THE INVENTION
The individual graphene structures of the present invention are able to absorb light very efficiently. We show in FIG. 1 calculated results for the cross section of nanodisks and nanoribbons. These calculations, and the ones discussed below, are performed by solving Maxwell's equations using a realistic description of the graphene using the local random-phase approximation [F. H. L. Koppens, D. E. Chang, and F. J. García de Abajo, Graphene Plasmonics: A Platform for Strong Light-Matter interactions, Nano Letters 11, 3370-3377 (2011)]. For disks ( FIG. 1A ), the diameter and Fermi energy (i.e., the level of doping) is indicated for each absorption spectrum. For ribbons ( FIG. 1B ), we represent the absorption cross section as a function of ribbon width for fixed Fermi energy (0.2 eV). The absorption cross section is defined as the effective area on which impinging light is absorbed. The plots here show a large increase in the absorption cross-section at specific light wavelengths corresponding to those capable of exciting the plasmons in nanodisks ( FIG. 1A ) and nanoribbons ( FIG. 1B ). The absorption cross section reaches values exceeding the geometrical cross section of the graphene structures. The significance of such large cross section is twofold: first, it allows us to absorb much more energy per unit of graphene area than a homogeneous graphene sheet; and furthermore, it allows us to absorb as much as 100% (see below) with a suitable distribution of nanodisks or nanoribbons. Obviously, these results are not restricted to nanodisks or nanoribbons, but they can be achieved with other patterns, for example, triangles, hexagons, etc. In particular, triangles and hexagons can be advantageous because they allow selecting uniform crystallographic directions of the graphene edges, thus minimizing undesired losses due to edge effects in structures of small size below a few tens of nanometers.
In a graphene layer, the absorption can be maximized when the absorption cross-section of the individual components of the structure exceeds their geometrical cross section [S. Thongrattanasiri, F. H. L. Koppens, and F. J. García de Abajo, Complete Optical Absorption in Periodically Patterned Graphene, Physical Review Letters (in press)]. These are the conditions shown above for graphene nanodisks and nanoribbons. We show in FIG. 2 that this leads to 100% absorption in the case of nanodisks. Similar calculations for nanoribbons show 100% absorption as well under similar conditions. FIG. 2A shows a scheme of a periodic array of graphene disks sitting at the interface between two different dielectrics. Similarly, complete optical absorption is also obtained for an array of graphene ribbons (not shown). FIGS. 2B and 2C show absorption spectra calculated for arrays of graphene disks and different parameters of the angle of incidence, incident light polarization, and dielectric constants of the two media surrounding the graphene. The light is coming from medium labelled with medium 1 in FIG. 2A . Under total internal reflection conditions, we find 100% absorption of the light at a photon energy of 60 meV. This energy can be tuned by changing the Fermi energy or the geometrical parameters. Similar results are observed for peaks of absorption within the infrared part of the spectrum. In FIGS. 2D and 2E , we show absorption spectra for periodic arrays of graphene sitting on a dielectric layer on top of a gold substrate. The absorption is again 100% when the patterned graphene is periodically arranged. Again, the photon energy at which this maximum occurs can be tuned by changing the Fermi energy or the geometrical parameters. FIG. 2E shows that this effect occurs for a broad range of angles, and thus, the complete optical absorption effect is omnidirectional. These results are the basis of the devices provided in this document and discussed below. Similar results are obtained for arrays of graphene ribbons or other periodic patterns of graphene. Non-periodic structures can also produce large absorption, but not 100% in general, at peak wavelengths depending on the local geometry. It is important to bear in mind that 100% absorption requires either total internal reflection ( FIGS. 2B and 2C ) or a so-called Salisbury screen ( FIG. 2D ), as well as a suitable choice of geometrical parameters. The exact conditions under which the effect occurs are well established from simulations: (i) one starts with disks or ribbons showing an absorption cross-section exceeding their areas when they are considered individually (this condition is given for specific combinations of sizes and doping levels, an example of which is shown in FIG. 1 , but more results are easily obtained from an exhaustive search of parameters based upon the simulations described above, in order to guide actual implementations); (ii) then one constructs arrays (e.g., square or hexagonal arrays of disks, or 1D gratings of aligned ribbons, in which the ribbons are separated by a certain distance; all of these arrays have the graphene in the same plane, on top of a substrate); (iii) the remaining parameter is the separation (i.e., the array lattice constant) between graphene elements (e.g., disks or ribbons), in order to obtain 100% absorption, as shown in the examples provided in FIG. 2 (a similar simulation search can be carried out for elements with the desired size and doping level). Complete absorption is always possible by exploiting these configurations, provided the graphene units of the periodic structure have a cross section exceeding the area of the unit cell [S. Thongrattanasiri, F. H. L. Koppens, and F. J. García de Abajo, Complete Optical Absorption in Periodically Patterned Graphene, Physical Review Letters (in press)]. Nonetheless, the use of graphene disks, ribbons, or other graphene patterns produces plasmons that resonate at specific light wavelengths, leading to enhanced light absorption at those wavelengths.
FIG. 3A shows an example of how to dope an array of graphene nanoribbons, patterned on a dielectric substrate that includes a backgate. A contact at one end of the ribbons (this can be made of metal deposited by, for example, lithographic methods, or it can be part of the graphene, which is contacted to an external lead far away from the ribbon structure) provides a difference in potential between the graphene and a backgate layer immediately below the dielectric substrate, which is compensated by charging the ribbons. The applied voltage V controls the amount of charging or doping (i.e., the Fermi energy of the ribbons). The backgate can be made of conducting doped silicon (this is convenient if a dielectric silica layer is made by oxidation of the silicon). If made of a metal layer grown underneath the dielectric substrate, the metallic Salisbury screen as discussed above is achieved, this having the advantage that the device has a 100% efficiency.
FIG. 3B shows another embodiment with graphene nanoribbons on top of a gate electrode separated by an insulating layer. Additionally, local gate electrodes are deposited below the nanoribbons. By applying the appropriate voltages to the gates, pn-junctions in the ribbons can be formed (to be used in the photovoltaic devices described below). Light absorbed in the ribbons is converted into an electronic signal (current flow or voltage). Modifications to this design include the following possibilities: (i) ribbons can be replaced by other shapes (disks, holes in graphene, graphene on patterned substrate, etc.); (ii) graphene can be replaced by bilayer graphene, so that the gates can open a bandgap and pn-junctions at the same time, thus enabling this device to generate power from absorbed light (for photovoltaics discussed below); (iii) the gates can be metal, ITO, conducting polymer, graphene, nanotubes, or any other conducting material, or a combination of materials; (iv) on top of the local gates, a thin layer of oxide can be deposited, and this oxide can be SiO 2 2 , MgO 2 , HfO 2 , TiO 2 , or any other insulating material. Multilayer graphene can also be employed, rather than monolayer or bilayer graphene.
FIG. 3C shows yet another embodiment, in which the graphene pattern can be non-uniform along the device in order to realize light absorption only locally (for example close to the pn-junction).
FIG. 3D shows yet another embodiment, in which different graphene patterns are stacked on top of each other. Extra gates in between the layer provide independent tunability of the doping in the graphene.
FIG. 3E shows yet another variation, in which instead of patterning the graphene, the substrate (with graphene on top) or local gates can be patterned. The operation of the device is then based on the dielectric contrast defined by the substrate, or by the electrostatic potential profile, defined by the substrate or gates. The substrate or metallic gate modifies locally the plasmonic properties of the material. By patterning the substrate or gates, the graphene plasmonic properties can be patterned as well. This leads to effectively the same plasmonic properties as patterned graphene.
Specifically, FIG. 3E shows metallic gates, patterned in ribbons, with graphene deposited on top, and a thin insulating layer separating electrically the local gates from the graphene. Additionally, FIG. 3F shows a patterned substrate (e.g., trenches in an insulator, with graphene deposited on top). A possible variation of the graphene devices provided above consists of employing SiC as the substrate material. This produces large variations in the optical response with small variations in wavelength.
Electrostatic doping can be achieved in a variety of ways. Rather than a backgate configuration, as depicted in some of the figures, one can use a biased metallic tip placed close to the graphene. Alternatively, one can use metal leads placed near the graphene on the plane of the dielectric substrate, but without actual contact with the graphene, so that doping is induced in the carbon sheet in order to screen the fields produced by the leads. Alternatively, one can use substrate materials that induce doping in the graphene, due to chemical processes or due to polarization charges present at the surface. The electric field generated by the substrate can then induce high carrier densities in the graphene.
Yet another variation consists in using a strong microwave or radiowave signal to produce a strong electric field near the graphene structures. This is particularly suited for the graphene disks. The electric field thus produces a redistribution of charges in the graphene by direct polarization, and the regions with excess of charge can thus sustain plasmons of a frequency that depends on the density of that charge, which is in turn proportional to the intensity of the applied external microwave or radiowave signal. A similar scheme can be used for other frequencies of the applied radiation, down to a DC electric field.
FIG. 4 shows a possible design of a spectral photodetector. It includes the same doping elements as in FIGS. 3A-3D . Besides, the graphene ribbons have two different regions: one of larger width and another one of smaller width. They are designed to resonate with the light in one of these regions (for example, the wider ribbon region). This is heated by the incident light because it is in resonance with the incidence light wavelength, whereas the thinner region is not heated the same because it is not on resonance. Two contacts are then provided, one for each region. Since the wider region and its contact are heated at a higher temperature than the narrower region and its contact, this forms a thermocouple. The voltage produced by the temperature difference in the thermocouple is thus roughly proportional to the amount of light being absorbed by the wider region (minus the amount of light absorbed in the narrower region, designed to absorb negligibly). The voltage reading, after calibration, thus provides a direct reading of the incident light intensity at the wavelength for which the resonance in the wider region graphene is placed. The two contacts can be made of either the same conductor or different conductors. It can also be made of graphene with a different doping level. In any case, the material in the contacts has to differ from the graphene in the ribbons in order to form the noted thermocouple.
Alternatively, rather than patterning the ribbons, they can be of homogeneous width and the backgate can be patterned laterally (e.g., divided into two separate backgates at different potential) or vertically (e.g., it can be at a different distance from the graphene ribbons in one region. Either of these configurations produces a doping level that is different in one of the regions of the graphene ribbons compared to the other region, so that one of the regions resonates to a given wavelength, whereas the other can be made to not resonate at all. Thus, the resulting structure has a similar functionality as the ones depicted in FIGS. 3A-3D , but instead of physically making the ribbons of varying width in each region, it is the backgate that is either placed at a difference distance from the graphene (e.g., but changing the thickness of the dielectric substrate layer) or divided into two backgates, each at a different potential.
To be more specific, a graphene structure can act as a light spectral detector as follows: light is absorbed by the graphene, but mainly light of the same frequency as the plasmon frequency will be absorbed, so a given structure will be most sensitive to a color of the light determined by the plasmon frequency; this light absorption will produce a change in local temperature in the graphene and in some of the elements near it; this will in turn induce a Seebeck (thermoelectric) effect, thus resulting in a net electrical signal; this signal is roughly proportional to the light intensity at the selected plasmon frequency; either by using an array of such graphene structures, tuned to a series of frequencies covering the desired spectral region, or by repeatedly using the same graphene structure that is electrostatically tuned to swap the desired spectral region through its plasmons, this detection procedure yields a light spectrum. Graphene plasmons are naturally situated in the infrared to THz range, thus covering a difficult spectral range, in which efficient spectral detectors are lacking.
Likewise, the graphene structure of the invention can act as an IR source as follows: the graphene is heated to a temperature T above room temperature; thermal emission will then occur within a wavelength range around b/T, where b=2.9 mm K is the Wien displacement constant (e.g., emission around 6 micron wavelength when T is 200 C); because of Kirchhoff s law, the emission will be proportional to the absorption at the same wavelength, which is in turn boosted at the plasmon frequencies; thus, a source of IR radiation is provided, peaked around the usually narrow graphene plasmons; these plasmons can be moved in frequency via electrostatic doping, thus resulting in a tunable IR source, again within a spectral range in which sources are scarce and expensive. This presents a viable, cheap alternative to other existing technologies, such as quantum cascade lasers.
Two possible implementations of tunable sources are provided in FIG. 5 . FIG. 5 shows an array of graphene ribbons, with plasmons tuned via backgate electrostatic doping, and two contacts (one of them can also be used for doping) create a current I through the graphene, which raises the temperature in the graphene by Joule electric losses, and thus produces thermal emission with a preferential tuned wavelength. In FIG. 5B , another alternative device is shown, in which heating occurs through a current running along the backgate.
Besides electrostatic doping, the charging of graphene can depend on the ambient conditions, particularly if the graphene is surrounded by a fluid. The pH condition of the fluid, or its chemical composition can affect the doping, and thus, the wavelength of the resulting plasmons supported by the graphene depends on the pH and the chemical composition of the fluid (e.g., on the concentration of different substances). In such a device, with the graphene surrounded by a fluid, the spectral photodetector is also a sensor: with fixed illumination with light of wavelength tuned to the plasmons of the graphene surrounded by a base fluid, any changes in the composition of the fluid that result in plasmon wavelength shifting will move the resonance away from the illuminating wavelength, thus producing a decrease in absorption. This can be detected through the thermocouple potential, thus revealing a change in the composition of the fluid.
A thermoelectric photodetector can be constructed in a similar way by placing a plasmonic structure (e.g., a nanoparticle, or any other patterned structure) close to a contact between two different conductors (e.g., two different metals, or even graphene and a metal), so that light absorption mediated by the plasmon of the plasmonic structure produces heating of the contact and therefore also a voltage induced by the Seebeck effect. This voltage is then read and it is roughly proportional to the amount of light being shone on the structure at the plasmon frequency. This type of device operates at a single wavelength. A spectral photodetector can then be constructed with an array of such detectors, each of them designed for a different wavelength, and with the set of detectors covering the desired spectral region (i.e., their resonant wavelengths must be separated by the width of the plasmon wavelengths, so that they cover the spectral region of interest exhaustively). This type of device can operate in the visible, near-infrared, infrared and THz.
FIGS. 6 , 7 , and 8 show several arrangements of p-type and n-type semiconductors placed in contact with the patterned graphene, along with the necessary contacts to extract electrons and holes produced upon light absorption in the latter. In all embodiments, the graphene is in contact with p-type semiconductor, or n-type semiconductor, or both of them (one on each side of the graphene), so that electron-hole separation takes place by releasing these charge carriers through semiconductors of different doping, and from here to the metal contact to close the circuit an to be used as a source of electrical power.
FIG. 6 shows patterned graphene, sandwiched between p and n-type semiconducting materials. An insulating layer prevents direct contact between the p and n-type semiconducting materials.
FIG. 7 shows an alternative configuration to FIG. 6 where the graphene pattern varies laterally. Therefore, the wavelength sensitivity varies laterally.
FIG. 8 shows an alternative configuration to FIG. 6 , consisting of a stack of patterned graphene sandwiched in between p and n-type semiconductors. The wavelength sensitivity varies vertically. In total this configuration is therefore intended to capture a larger wavelength range of incoming light.
Collection of IR radiation by the graphene structures of the invention can be done as follows: a graphene structure is patterned such that it absorbs light corresponding to a given plasmon frequency; the doping and decorating elements in the graphene are selected in order to promote electron-hole separation; such structure will then convert photons at the plasmon frequency into electrical signals; a stack of such structures is then made, each of them converting a certain part of the spectrum into electricity; alternatively, a parallel display with such structures of varying frequency are arranged so that they are exposed to light of the corresponding frequencies after the light has been spectrally separated by a prism or grating.
The invention finds application in a number of technologies such as security screening, microscope spectral imaging, IR vision, medical diagnosis, with optical IR probes, microscale product coding, optical signal processing and many more.
In this text, the term “comprises” and its derivations (such as “comprising”, etc.) should not be understood in an excluding sense, that is, these terms should not be interpreted as excluding the possibility that what is described and defined may include further elements. On the other hand, the invention is obviously not limited to the specific embodiment(s) described herein, but also encompasses any variations that may be considered by any person skilled in the art (for example, as regards the choice of materials, dimensions, components, configuration, etc.), within the spirit of the invention. | An infrared photoconversion device comprising a collector with at least an active layer made of a single sheet of doped single-layer, bilayer, or multilayer graphene patterned as nanodisks or nanoribbons. The single sheet of doped graphene presents high absorbance and thus, the efficiency of devices such as photovoltaic cells, photodetectors, and light emission devices can be improved by using graphene as the central absorbing or emitting element. These devices become tunable because their peak absorption or emission wavelength is changed via electrostatic doping of the graphene. | 6 |
BACKGROUND OF THE INVENTION
The introduction of discrete fibers to a base knitting yarn during a knitting operation is an old technique for the production of knitted fabrics having a pile surface or effect. Generally, the pile knitting machines are equipped with a plurality of means around the perimeter thereof that supply discrete fibers to a position where the fibers are removed by knitting needles passing thereby. The fibers are then associated with a base yarn and knitted into the fabric with the ends of the fibers extending outwardly to provide the pile surface. Normally, the fiber feed means include apparatus which receives sliver or the like, cards and/or aligns the fibers and presents the worked fibers to the knitting needles. Development effort has been expended in the past to improve these feeding or card heads. For example, improvements have been made so as to better work the fibers; to increase the feeding capacity of the card heads; to vary the density of pile fibers knitted into the fabric; to mix feeds from adjacent systems; to handle various lengths of fibers, and the like.
Such attempts as set forth above have included various arrangements for presenting the fibers to a rotating working cylinder of the card head; proper handling of the fiber on the working cylinder and primarily, devices and techniques for removal of the fibers from the working cylinder and presenting same to the knitting needles as they pass thereby. The present invention represents yet another improvement for a knitting system for the production of pile fabrics. Present emphasis is directed to the card heads positioned around the knitting machine to improve output capacity, handling of shorter fibers and the like. The present invention affords advantages heretofore unavailable to the knitting industry and is a definite advance in the art.
As listed below, there is a voluminous amount of art in this particular area. The present invention is, however, neither suggested or taught by the patented prior art. Exemplary of this prior art are U.S. Pat. Nos. 1,114,414 to Tauber; 2,280,535 to Moore; 2,953,912 to Hill; 2,971,357 to Hill; 2,993,351 to Wheelock; 3,010,297 to Hill; 3,019,623 to Howes; 3,045,459 to Hill; 3,095,614 to Moore; 3,122,904 to Brandt; 3,153,335 to Hill; 3,188,834 to Radtke; 3,248,902 to Radtke; 3,295,337 to Beucus et al; 3,299,672 to Schmidt; 3,412,823 to Beucus et al; 3,447,343 to Frishman et al; 3,495,422 to Miller; 3,501,812 to Schmidt; 3,516,265 to Collez; 3,604,062 to Hollingsworth; 3,651,664 to Collez et al; and 3,685,315 to Delberghe.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide a novel system for the knitting of pile fabrics.
Another object of the present invention is to provide novel apparatus for the feeding of pile fibers to a knitting machine.
Still another object of the present invention is to provide a novel method for the feeding of pile fibers to a knitting machine.
Still further, another object of the present invention is to provide novel apparatus for the manufacture of knitted high pile fabric.
Yet another object of the present invention is to provide an improved card head for a pile fabric knitting machine.
Generally speaking, the apparatus of the present invention comprises a feed means for supplying a sliver of precarded, pre cut fibers to a rotatable cylinder having card clothing thereon, means cooperating with said cylinder for aligning and transporting said fibers without substantial embedding of said fibers and rotary means located just out of contact with said cylinder, said rotary means being rotatable at a speed higher than said cylinder and removing fibers therefrom, said rotary means further being located adjacent a knitting machine and presenting pile fibers to said machine.
More specifically, the pile fabric knitting machines, such as a Wildman Jacquard double knit machine, for example, knit a tubular fabric entrapping the pile fibers therein. Generally speaking, a plurality of card head feed units are positioned around the circumference of the knitting machine and supply staple pile fibers to the knitting machine from the various points of feed. A base fabric is then knitted in a conventional manner while simultaneously entrapping the pile fibers among the loops thereof. The pile fibers are held at one end thereof, with the remaining length extending outwardly from the fabric to provide a particular appearance or characteristic.
A preferred card head unit according to the present invention includes a main cylinder having card clothing thereon and being rotatable in a first direction. Feed means are positioned at one side of said main cylinder for supplying carded, pre cut sliver thereto, the feed means including a single rotatable combination fluted-toothed roll that cooperates with a highly polished nose plate guide adjacent thereto to supply fibers in sliver form to the rotatable main cylinder. The main cylinder rotates at a higher speed than the fluted roll and separates individual fibers from the sliver without substantially embedding the fibers in the clothing on the cylinder. A guide means is positioned above a portion of the periphery of the main cylinder at a predetermined distance therefrom and cooperates with the main cylinder clothing so as to work and direct the fibers preparatory to presenting same to the knitting needles. The inner surface of the guide may be smooth, knurled or may have a series of teeth thereon as defined in the U.S. Pat. No. 3,604,062 to Hollingsworth. On the exit side of the main cylinder and operatively associated therewith is a rotatable doffer roll having bristle type members received around the circumference thereof. The doffer is rotatable in a direction opposite to the direction of the main cylinder and the bristle members of the doffer are just out of contact with the clothing of the main cylinder. The doffer elements engage the individual fibers floating on the clothing of the main cylinder and remove the fibers therefrom. Moreover, the doffer rotates at a peripheral speed greater than the main cylinder so as to establish some drawing of the fibers for the successful removal thereof.
The bank of needles provided on the knitting machine pass across the doffer in a direction transverse to the direction of rotation of the doffer and strip the fibers therefrom. Means associated with the needles and the doffer prevent any interference from the doffer after the fibers have been received by the needles. Further, a guide progressively forces fibers downwardly along the shank of the needles, after which a base yarn is inserted into the eye of the needle above the fibers and the base fabric is knitted, entrapping the fibers in a conventional manner.
The card head unit according to the teachings of the present invention is further preferably constructed so as to control air currents therethrough. Improved fiber feeding to the knitting needles is thus fostered. In this regrd, the card head is enclosed around a portion thereof to direct air currents in the direction of movement of the fibers around the main cylinder. The doffer is also partially enclosed to direct air currents at the fiber transfer where the air is then exhausted from the vicinity of the knitting machine. An exhaust duct extends downwardly into the middle of the knitting machine just above the fabric take up roll. Air passing into the duct removes excess fibers, unbound fibers, lint and the like from the interior of the knitting machine. Furthermore, an air conduit is provided around the periphery of the knitting machine so as to remove lint and excess fibers from the outside of the knitting machine. The feed unit of the card head is also provided with air duct to remove waste from the main cylinder and the fluted feed roll. Accumulation of any fiber waste is thus substantially precluded whereby nebs and the like are not introduced into the system.
Card head units around the knitting machine are preferably associated with a universal drive system whereby all of the card heads may be simultaneously controlled. Fiber feeding speeds may thus be uniformly controlled to improve fabric uniformity and quality.
The method of the present invention generally involves the steps of supplying fibers to a card head for a high pile knitting machine, substantially floating the fibers through the card head while separating and aligning the fibers, removing the fibers from the card head while precluding contact with the card head, presenting individual fibers to knitting needles passing thereby in sequential fashion, said fibers being substantially centered around said needles; forcing said fibers downwardly along said needles; inserting a base yarn in the eyes of said needles above said fibers and knitting said yarn into a base fabric while simultaneously entrapping said fibers in said fabric at one end thereof.
More specifically, discrete carded fibers are fed in sliver form to the card head unit where the fibers are separated from the sliver by a main cylinder having card clothing therearound and rotating at a higher rate of speed than fibers being fed thereto. Care is taken to avoid fibers being forced down into the card clothing. Instead, the fibers float atop the card clothing as they are transferred by the rotating cylinder. Such floating action is possible due to the absence of a lickerin roll or the like, by using controlled air currents through the card head; spacing between the component parts and the like. The fibers remain in a substantially floating condition during the entire time they are on the cylinder and when presented to the doffer are properly removed thereby, leaving very little if any waste on the cylinder. Knitting needles moving sequentially across the surface of the rotating doffer engage the fibers at or near the center of the fiber length for removal. Those fibers otherwise engaged remain on the doffer. The needles move across the doffer in a direction transverse to the direction of rotation thereof and intermesh with the bristles or the like, each needle removing a predetermined amount of fiber therefrom.
As the individual needles move away from the doffer with fiber positioned therearound in a substantially uniform fashion, i.e., the needle contacts the center of the fibers a stationary guide is encountered, a lower inclined surface of which progressively forces the fibers downwardly along the needle shanks so as to enable a base yarn to be fed to the needles above the fibers. The base yarn is then knitted into a base fabric with the fibers around the needles being simultaneously entrapped therein at one end thereof. The remaining length of the fibers then extends above the surface of the base fabric providing the high pile surface effect.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a side elevational schematic view of apparatus embodying the present invention.
FIG. 2 is a cut away view showing fiber feed to a card head unit for a pile knitting machine according to the teachings of the present invention.
FIG. 3 is a cut away view of a portion of a card head attachment according to the present invention, illustrating a particular feature thereof.
FIG. 4 is a partial view in perspective illustrating a portion of the apparatus of the present invention and fiber transfer therealong.
FIG. 5 is an enlarged view of a portion of a pile knitting machine showing fiber handling by the knitting needles according to the present invention.
FIG. 6 is a schematic illustration of the air handling system according to the teachings of the present invention.
FIG. 7 is a top plan view of a knitting machine with card heads disposed therearound according to one embodiment of the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
A preferred embodiment of the present invention will now be described in detail with reference to the Figures. FIG. 1 schematically illustrates, in general, apparatus according to the present invention. A knitting machine generally indicated as 10 is provided for knitting the pile fabric, utilizing the apparatus and method of the present invention. A suitable knitting machine might be of the Wildman Jacquard type and is well known to those skilled in the art. A detailed description of the knitting machine is thus felt not necessary for a complete understanding of the present invention. Knitting machine 10 does, however, have a cylinder 12 extending therearound, and having a plurality of knitting needles 14 positioned thereon. A tubular knit fabric F' is produced and taken up on a suitable means 70 therefor.
At several points around the periphery of the knitting machine, only one of which is shown in FIG. 1, card heads generally indicated as 20 are positioned. The various card heads 20 are utilized to supply discrete staple fibers to the knitting needles 14 after which the pile fibers so supplied are entrapped in the base fabric as the fabric is knitted on knitting machine 10. Depending upon the desires of the individual and as described hereinafter, the plurality of card heads 20 are preferably controlled by a single drive means whereby the operational speed of same may be coordinated and controlled by a single adjustment (See FIG. 7). In addition to the knitting machine 10 and the card heads 20, an air handling system generally indicated as 40 is provided so as to properly handle air flow in and around the card heads 20 and the knitting machine 10 to further improve the operational efficiency of the apparatus and the process.
The apparatus of the present invention is further quite versatile. For example, fiber density on the ultimate fabric may be substantially varied by varying the density of sliver being fed to the card heads and/or varying the speed of the feed roll 24. Moreover, the apparatus can handle various lengths of fiber. In fact, fibers ranging in length from 3/4 inch to 41/2 inches may be employed without any adjustment to the card heads. Historically, great difficulty has been experienced in handling 3/4 inch fibers and also in achieving a proper high fiber density on the fabric without the presence of slubs. For example, a fiber density of at least 15 ounces per square yard may be achieved with higher densities of up to approximately 38 ounces per square yard of fabric likewise being possible.
The card heads 20 according to the teachings of the present invention comprise a main cylinder 22 having card clothing 23 received around the periphery thereof. Main cylinder 22 is journaled for rotation in a support frame (not shown) and serves a primary purpose of separating, transferring and aligning fibers in contact therewith prior to removal thereof at the doffer and feeding same to the knitting machine. A fluted roll with teeth 24 and a highly polished nose guard 25 cooperate to provide a feed means for supplying fiber to the main cylinder 22 adjacent one side thereof. Abutting nose guard 25 and extending around a portion of the circumference of main cylinder 22 is a peripheral guide or flat 26 which will be explained in greater detail hereinafter. It should be pointed out, however, that nose guard 25 is contiguous with guide 26. On the opposite side of main cylinder 22, a doffer 27 is received for rotation in a direction opposite to main cylinder 22. Doffer 27 has a plurality of fiber engaging elements such as bristles 28 or the like received therearound to engage fibers on main cylinder 22, remove same and present the fibers to knitting needles 14 passing thereacross. Doffer 27 and bristles 28 are located adjacent main cylinder 22 and do not contact the card clothing 23 of main cylinder 22. Instead, individual fibers being handled by the main cylinder 22 are engaged by bristles 28 during rotation of doffer 27. Due to the relative rotational speeds of doffer 27 and main cylinder 22, bristles 28 impale the fibers F and remove same from main cylinder 22.
Card head 20 further has an air guide 29 adjacent doffer 27, the purpose of which will be described in greater detail hereinafter. Furthermore, a bottom guide 30 is also provided, the purpose of which will be described in greater detail hereinafter.
Fibers picked up by bristles 28 of doffer 27 are presented to the knitting needles 14 that pass in a direction substantially transverse to the direction of rotation of doffer 27 and engage the fibers being held by bristles 28. Those fibers that are engaged at their approximate midpoint by needles 14 are removed from doffer 27 while others overcome the frictional resistance of needles 14 and remain on doffer 27 for another pass. Hence fibers are continually presented to needles 14 which pass in succession through the bristles 28 of doffer 27 and remove a particular amount therefrom. A fiber guard 31 is located immediately adjacent doffer 27, and is so positioned that once the fibers F are positioned around knitting needles 14, guard 31 is positioned between the fibers and bristles 28 whereby the fibers are protected against any later interference. Furthermore, as needles 14 continuously move around cylinder 12, air is directed thereagainst from a nozzle 32 which forces the ends of the fibers F inwardly towards the center of the knitting machine so as to properly position the fibers for subsequent entrappment in the knitted fabric. Immediately after movement away from doffer 27, fibers F on needles 14 are engaged by a vertical angularly presented guide plate 33 which may be best seen in FIG. 5. The angular presentation of guide plate 33 progressively forces fibers F downwardly along the shanks 14' of needles 14, after which a base yarn Y (shown in FIG. 5) is placed in the hooks 14" of the knitting needles 14 and is subsequently knitted into the base fabric while simultaneously entrapping fibers F therein so as to produce a knitted pile fabric.
The air handling system 40 as shown in FIGS. 1 and 6 comprises a first hood 42 that terminates above knitting machine 10 with the card heads positioned therearound in proximity thereto. A second hood 44 is concentric with hood 42 and extends downwardly therefrom inside knitting machine 10 so as to remove lint, excess fibers and the like from the inside portion of the knitting machine and from the fabric being knitted and taken up thereat. A manifold 46 also communicates with hood 42 and terminates at an exhaust conduit 48 that surrounds the upper portion of knitting machine 10. A second exhaust conduit 49 is positioned beneath each card head 20 adjacent the fiber feed system and communicates with hood 42 in conduit 48. Air suction means schematically illustrated as 50 are operatively associated with the main hood 42 and hence with all of the exhaust systems so as to create air suction therethrough. Air suction through the system creates air currents around the affected areas of the knitting machine and remove lint, fly and the like from the areas which the individual elements serve. The particular operation of the air handling system of the present invention will be described in greater detail hereinafter.
An important feature of the present invention is proper handling of the fibers in a particular fashion. FIGS. 2 and 3 illustrate working of the fibers and apparatus therefor as follows. The main cylinder 22 having appropriate card clothing 23 received therearound rotates in a direction indicated by the arrow. Fiber F is fed in the form of a sliver, roving or the like (not shown) to the card head from a source such as sliver can or the like. Fluted, toothed roll 24 compresses fibers F against nose guard 25 and pulls the fibers therethrough. In so doing, there is some drawing of the fibers during feeding. Guide 25 has a nose portion 25' around which fibers F pass. Nose portion 25' of guide 25 is preferably highly polished metal to insure proper passage of fibers therearound, and is positioned a predetermined distance away from the card clothing 23 of main cylinder 22. Fibers exit from the feed means into the path of rotating main cylinder 22, where they are engaged by card clothing 23 and separated from the sliver. No appreciable pressure is exerted against the fibers at main cylinder 22 whereby the fibers are not appreciably embedded in the card clothing 23. Instead, fibers F float on top of the card clothing during rotation of main cylinder 22. Obviously, a certain amount of fiber embedding must occur. There is, however, in the sense of the present invention, no substantial embedding of fibers in card clothing 23 which provides a cleaner system, reduces nebs, and enables better fiber alignment. Note, for example, in FIGS. 2 and 3 that separated fibers F are shown floating on card clothing 23 of main cylinder 22, and not embedded therein. As fibers F pass around main cylinder 22, curved guide 26 takes over where guide 25 leaves off. Guide 26 as mentioned above may have a smooth or other surface. An irregular surface on the underside of guide 26 is illustrated in the Figures. The irregular surface cooperates with card clothing 23 so as to properly work fibers F during passage thereby, prior to their being fed to the knitting machine. Preferably, the irregular surface 26' is represented by a plurality of steel teeth secured to guide 26 and angularly disposed in a direction opposite the direction of rotation of the main cylinder. This particular configuration is of the general type described in U.S. Pat. No. 3,604,062 to Hollingsworth.
FIG. 4 is provided to better illustrate fiber transfer through the card head 20 to the needles 14 of knitting machine 10. The fibers F during transfer, as mentioned above, are floating on the clothing 23 of the main cylinder 22 rotating at a particular speed in a clockwise direction, for example. The doffer 27 having bristles or the like 28 thereon rotates in an opposite direction, counterclockwise, for example, such that bristles 28 and clothing 23 pass each other at the point of fiber transfer. Bristles 28 are barely out of contact with the clothing 23 of main cylinder 22 and doffer 27 rotates at a speed higher than main cylinder 22 so as to facilitate fiber transfer. In other words, as bristles 28 approach a point of convergence with main cylinder 22, bristles 28 engage fibers F that are floating on clothing 23 and lift same therefrom, the fibers being impaled by bristles 28. As doffer 27 rotates, needles 14 of knitting machine 10 successively pass by the bristles 28, engaging the fibers F and removing such fibers as are contacted at their approximate mid points thereby. A protective guard 31 secured to a framework (not shown) is positioned adjacent the path of needles 14 and precludes interference with fibers F by bristles 28 once the fibers are received on needles 14 and leave doffer 27. An air nozzle of comb 32' is further provided adjacent the fiber receiving area so as to provide an air stream against the fibers and cause the fiber ends to extend inwardly with respect to knitting machine 10.
To insure proper entrappment of fibers F in the base knitted yarn, it is desirable to present the fibers beneath a base yarn Y that is to be knitted by needles 14. This is accomplished by securing a guide 33 as is best seen in FIGS. 4 and 5 in the path of needles 14 as they leave doffer 27. Guide 33 has an inclined lower surface 33', angling downwardly away from doffer 27 along the needle path and forces fibers F progressively downwardly along the shanks 14' of needles 14. As the fibers F are being forced downwardly along needles 14, a base yarn Y is then passed through a thread guide 34 and inserted in the hooks, 14" of needles 14 as is shown in FIG. 5. Yarn Y is fed by a conventional means and the feeding of same is thus not elaborated on herein.
Making reference to FIG. 6, the air system of the present invention will be described. Proper air flow through the card heads 20 positioned around knitting machine 10 further improves the overall operation of the apparatus and method of the present invention. In this regard, note that a first hood 42 is positioned adjacent doffer 27, above knitting machine 10. A suction means generally indicated as 50 produces air currents upwardly through hood 42 from the area surrounding opening 42'. Main cylinder 22 is provided on its top as shown in FIGS. 1 and 2 with nose guide 25, arcuate guide 26 and air guide 29 that partially surrounds doffer 27. Air flow is thus directed from the fiber feed system around main cylinder 22 over the top half thereof, under doffer 27 and up, into hood 42. These air currents, of course, remove loose fly and lint from the system and further, insofar as card heads 20 are concerned, assist in floating fibers F through the card heads per se. A second hood 44 extends concentrically from within first hood 42 down into knitting machine 10 and removes loose fibers, fly, lint, trash and the like from the inside of knitting machine 10. Likewise, a manifold 46 extends from within hood 42 and downwardly to an exhaust conduit 48 that is positioned around the exterior of knitting machine 10 adjacent needle cylinder 12 to remove unwanted materials from that area. A further exhaust conduit 49 is operatively associated with the feed system of each card head 20. As shown in FIGS. 1 and 6, conduit 49 is positioned just below fluted roll 24 of the fiber feed system, and adjacent perforated screen 30. Header 49 thus removes waste fiber from the feed system as well as waste fiber that was not transferred by doffer 27 and continues to pass around main cylinder 22. Nebs are thus held at a minimum.
FIG. 7 illustrates a preferred feed drive system for the card heads of the present invention. The feed means, illustrated by the fluted rolls 24 of each card head 20 are provided with drive rods 81, 82, 83, 84 and 85 for the four card heads. These drive rods, through universal couplings 81', 82', 83', 84' and 85', respectively, connect all of the feed systems through a single variable speed drive unit 80. As such, the feed rate of all of the card heads 20 may be controlled through the single drive unit 80 and the feed rate of all the units may be simultaneously changed by a single adjustment of drive unit 80. Corresponding feed rate adjustments are then conveyed through the respective drive rods from feed unit to feed unit around the knitting machine. Utilizing this preferred arrangement, it is not necessary, once the system is initially adjusted, to make additional modifications to the individual feed heads 20. Better uniformity of fiber feed is thus realized.
Having described the apparatus of the present invention, the method of operation will now be described with reference to FIG. 1.
A rope, sliver or the like of fiber F is engaged by a fluted feed roll 24 at each of the feed units 20 positioned around knitting machine 10. Rotation of roll 24 draws fiber F thereby and presents a continuous fiber flow around nose 25' of guide 25 to a rotating main cylinder 22. Fibers F are engaged thereat by clothing 23 of main cylinder 22, separated from the sliver and follow the rotary movement of the cylinder without becoming substantially embedded in the card clothing. As the fibers pass around the main cylinder, they are worked by main cylinder 22 in cooperation with arcuate guide 26 to properly align same. All the while, the fibers are floating on main cylinder 22 without becoming substantially embedded therein. As the fibers move around cylinder 22, they approach doffer 27 havving a plurality of bristles 28 received therearound and extending outwardly therefrom. Doffer 27 is rotating in the opposite direction of main cylinder 22 at a higher surface speed than main cylinder 22. As such, bristles 28, without engaging card clothing 23, lift fibers F from main cylinder 22 and present them to successive knitting needles 14 that pass by bristles 28 of doffer 27. Needles 14 pass in a direction transverse to the direction of rotation of doffer 27 and as such strip fibers F therefrom. During the operation, air currents are channeled in the direction of fiber feed through the unit and assist in removing lint, fly and the like from the card head while further assisting in floating fibers F between the main cylinder 22 and guide 26.
Once the fibers F are stripped from doffer 27 by needles 14, an adjacent guard 31 prevents any further interaction between the fibers F and the bristles 28 of doffer 27. Immediately thereafter, needles 14 with fiber bunches thereon receive an air blast which positions fiber ends internally of needles 14. Needles 14 then engage an angled guide 33 which progressively forces fibers F downwardly along the shanks 14' of needles 14. A base yarn Y is then inserted into the hooks 14" of needles 14 and knitted into a base fabric (not shown). Once the fibers F are received around the needles 14 with a base yarn positioned thereover, the knitting machine knits the base yarn into a base fabric while simultaneously entrapping individual fibers F in bunches so as to produce a pile fabric. In utilizing the method and apparatus of the present invention, a pile fabric may be realized having a greater density, better cover and the capability of having shorter fiber secured therein.
Having described the present invention in detail, it is obvious that one skilled in the art will be able to make variations and modifications thereto without departing from the scope of the invention. Accordingly, the scope of the present invention should be determined only by the claims appended hereto. | A card head for supplying pile fibers to a knitting machine is disclosed herein along with a method for using same. Precarded, pre cut fibers in sliver form are presented to a fluted roll in proximity to a highly polished nose guide. Sliver is fed therethrough to a clothed main cylinder rotating at a higher speed than the fluted roll to separate cut fibers from the sliver. Flats or the like are secured around a portion of the main cylinder and cooperate with the main cylinder in proper alignment of fibers floating thereon. A doffer roll is positioned adjacent the end of the flats, barely out of contact with the card clothing and rotating at a higher speed than the main cylinder. Teeth on the doffer thus remove the fibers from the main cylinder and properly present same to knitting needles passing thereacross. The card head is provided with cover plates to control air flow therethrough which assists in floating of the fibers and proper operation thereof. Likewise, a combination air-guide arrangement is employed to properly position the fibers around the shank of the needles preparatory to knitting. | 3 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a method of assembling a carriage assembly for use in a magnetic disk apparatus where suspensions are attached to front end portions of carriage arms, and to an assembling apparatus that uses such method.
2. Related Art
FIG. 3 is a view showing the external appearance of a carriage assembly used in a magnetic disk apparatus. In FIG. 3 , reference numeral 10 designates carriage arms and 12 one example of a suspension that is connected to front ends of the carriage arms 10 . A magnetic head 14 is mounted on a front end portion of each suspension 12 . Each magnetic head 14 is electrically connected via a flexible circuit board 16 , which is attached to side surfaces of the carriage arms 10 , to a control unit 18 . Reference numeral 19 designates an actuator shaft that is fixed to a base portion of the carriage arms 10 . The carriage arms 10 rotate about the axis of the actuator shaft 19 to carry out seek operations on flat planes that are parallel to the surfaces of recording media.
The carriage assembly is formed by fixing each suspension 12 by crimping to both surfaces of a front end portion of one out of the carriage arms 10 that are attached to the actuator shaft 19 so as to be parallel to one another.
A conventional method of fixing the suspensions 12 to the carriage arms 10 is disclosed by Patent Document 1. FIG. 5 shows the conventional method of fixing the suspensions 12 to the carriage arms 10 disclosed in Patent Document 1.
According to this conventional method, after the suspensions 12 have been aligned with and placed upon the front ends of the respective carriage arms 10 , a metal ball 20 formed with a slightly larger diameter than an inner diameter of spacer holes 12 b provided in the suspensions 12 is passed through the spacer holes 12 b to fix the suspensions 12 to the carriage arms 10 by crimping. Reference numeral 22 designates a pressing shaft for pressing the metal ball 20 to cause the metal ball 20 to pass through the spacer holes 12 b.
FIG. 4 shows an operation that passes the metal ball 20 through the spacer holes 12 b of the suspensions 12 to fix the suspensions 12 to the carriage arms 10 by crimping. The suspensions 12 are placed on both surfaces of the respective carriage arms 10 with the fitting holes 10 a and the spacer holes 12 b in alignment. Since the metal ball 20 is formed with a slightly larger diameter than the spacer holes 12 b , when the metal ball 20 is passed through the spacer holes 12 b , the metal ball 20 acts so as to press open crimping portions 13 formed on inner circumferential edges of the spacer holes 12 b , and as a result, the suspensions 12 are fixed so as to “bite into” the carriage arms 10 . As shown in FIG. 4 , during a single crimping operation, the metal ball 20 is caused by the pressing shaft 22 to move successively through the spacer holes 12 b.
In this way, when assembling a carriage assembly, conventionally the metal ball 20 is used to press open the spacer holes 12 b to fix the suspensions 12 to the carriage arms 10 by crimping. Accordingly, depending on the balance between the external diameter of the metal ball 20 and the internal diameter of the spacer holes 12 b , a problem can occur where the spacer portions 12 a deform due to stress that acts thereupon during crimping, resulting in the suspensions 12 becoming displaced from the standard positions. That is, when the suspensions 12 are fixed to the carriage arms 10 by crimping, the spacer portions 12 a become bent, which can result in the suspensions 12 becoming tilted with respect to the standard angle. Tilting of the suspensions 12 affects the float heights of the magnetic heads 14 above the surfaces of the recording media, resulting in fluctuation in the float heights of the magnetic heads 14 above the surfaces of the recording media.
The storage capacity of modern magnetic disk apparatuses has been greatly increased, which has led to the float height of magnetic heads above the surfaces of recording media being kept low. This means that fluctuations in the float height of magnetic heads have a large effect on the information reading and writing characteristics, and therefore there are demands for the suppression of fluctuation in the float height of the magnetic heads to produce the required characteristics.
Patent Document 1 discloses a method of assembling a carriage assembly that can suppress deformation of the spacer portions 12 a due to the stress applied during crimping. FIG. 6 is a diagram useful in explaining a method of assembling a carriage assembly using an ultrasonic horn 32 disclosed in Patent Document 1 as a method of assembling that can suppress deformation.
The method of assembling a carriage assembly disclosed in Patent Document 1 is characterized by using the ultrasonic horn 32 to pass the metal ball 20 through the spacer holes 12 b . The metal ball 20 is the same as the metal ball 20 used in the method of assembling a carriage assembly described above. FIG. 6 shows a state of an assembly where gap maintaining plates 36 are inserted between adjacent carriage arms 10 and pressure applying plates 37 a , 37 b are placed in contact with both end surfaces of the carriage arms 10 so that the respective carriage arms 10 are supported by being sandwiched on both sides thereof.
The ultrasonic horn 32 applies ultrasonic vibration in the axial direction and due to the action of the ultrasonic horn 32 , the metal ball 20 causes less damage to the spacer portions 12 a during crimping, so that deformation is prevented when the suspensions 12 are attached to the carriage arms 10 and the suspensions 12 can be fixed to the carriage arms 10 more accurately. The reason for this is thought to be that the stress caused by the ultrasonic vibration of the ultrasonic horn 32 and the static stress due to the metal ball 20 pressing open the crimping portions 13 act so as to be superimposed, which makes it possible to reduce the resistance to deformation, and by reducing the average machining force by using a striking action that is repeated at high speed, it is possible to fix the members while suppressing deformation of the fixed portions of the suspensions 12 and the carriage arms 10 .
Patent Document 1
Japanese Laid-Open Patent Publication No. 2004-127491 (see paragraphs 0003, 0004, 0015, 0023, and 0024 and FIGS. 3, 5, and 6).
However, with the above conventional method of assembling a carriage assembly that uses ultrasonic vibration, it is not possible to completely avoid deformation of the spacer portions 12 a and therefore it is not possible to completely avoid fluctuations in the float amount of the magnetic head 14 from the surface of the recording medium due to displacement of the suspensions from the standard positions.
For this reason, there is much demand for a method of assembling a carriage assembly that can further reduce deformation in the spacer portions when suspensions are attached to carriage arms.
SUMMARY OF THE INVENTION
The present invention was conceived to solve the problem described above and it is an object of the present invention to provide a method of assembling a carriage assembly that compared to the conventional method can suppress deformation in spacer portions when suspensions are attached to carriage arms and can therefore further suppress fluctuation in the float height of magnetic heads from the surfaces of the recording media, and also an assembling apparatus that uses such method.
To solve the above problem, a method of assembling a carriage assembly according to the present invention aligns fitting holes provided in front end portions of carriage arms used in a magnetic disk apparatus and spacer holes provided in spacer portions of suspensions and places the suspensions onto the carriage arms, and then presses a ball with a diameter equal to or greater than an inner diameter of the spacer holes with a pressure-applying member to pass the ball through the spacer holes to crimp spacer hole edge portions of the spacer portions and attach the suspensions to the front end portions of the carriage arms, wherein by applying ultrasonic vibration from two axial directions to the pressure-applying member, the pressure applying member is caused to vibrate on a two dimensional movement path on a predetermined plane and passes the ball through the spacer holes while causing the ball to rotate.
By doing so, by applying ultrasonic vibration from two axial directions to the pressure applying member, the pressure applying member can be caused to move on a predetermined curved movement path on a predetermined plane. Accordingly, although the ball is pressed by a pressure applying member (ultrasonic horn) that vibrates only in the pressing direction (the axial direction of the spacer holes) in the conventional art and therefore the ball hardly rotates, with the invention of Claim 1 , since the pressure applying member that applies pressure to the ball contacts the ball while tracing a two dimensional movement path, the ball can be passed through the spacer holes while rotating. The present inventors discovered that by doing so, excessive force is not applied to the spacer portions when the ball passes through the spacer holes, and therefore there is reduced deformation in the spacer portions.
In addition, by applying ultrasonic vibration with frequencies that are integer multiples of a predetermined frequency to the pressure-applying member from the two axial directions, the ball may be caused to pass through the spacer holes while rotating in a predetermined direction.
By doing so, the direction of movement of the pressure applying member at the instant when the pressure-applying member contacts the ball is set at a predetermined direction, and therefore the ball can be passed through the spacer holes while rotating in a predetermined direction. The present inventors discovered that by doing so, it is possible to further avoid having an excessive force applied to the spacer portions when the ball passes through the spacer holes and therefore deformation of the spacer portions is reduced.
In addition, the movement path of the pressure-applying member due to the ultrasonic vibration may be one of a circle and an oval.
By doing so, it is possible to use a simple construction that sets the frequencies of the ultrasonic vibration applied from the two axial directions equally.
Also, ultrasonic vibration may be applied to the pressure-applying member from two axial directions that are a pressing direction for the ball and a direction perpendicular to the pressing direction to cause the pressure-applying member to vibrate with a movement path on a plane parallel to the pressing direction and cause the ball to rotate about a rotational axis that is substantially perpendicular to the pressing direction.
By doing so, it is possible to cause the ball to rotate about a rotational axis that is substantially perpendicular to the pressing direction. The present inventors discovered that by doing so, it is possible to further avoid having an excessive force applied to the spacer portions when the ball passes through the spacer holes and therefore deformation of the spacer portions is reduced.
To solve the above problem, an assembling apparatus for a carriage assembly according to the present invention aligns fitting holes provided in front end portions of carriage arms used in a magnetic disk apparatus and spacer holes provided in spacer portions of suspensions and places the suspensions onto the carriage arms, and then passes a ball with a diameter equal to or greater than an inner diameter of the spacer holes through the spacer holes to crimp spacer hole edge portions of the spacer portions and attach the suspensions to the front end portions of the carriage arms, the assembling apparatus including: a pressure-applying member; a driving device that moves the pressure-applying member so that the pressure-applying member presses the ball to pass the ball through the spacer holes; and ultrasonic vibrating means that causes the pressure-applying member to vibrate on a two dimensional movement path on a predetermined plane by applying ultrasonic vibration to the pressure-applying member from two axial directions to cause the ball that passes through the spacer holes to rotate.
With the above construction, by applying ultrasonic vibration from two axial directions to the pressure-applying member, the pressure-applying member can be caused to move on a predetermined curved movement path on a predetermined plane. Accordingly, although the ball is pressed by a pressure-applying member (ultrasonic horn) that vibrates only in the pressing direction (the axial direction of the spacer holes) in the conventional art and therefore the ball hardly rotates, with the invention of claim 5 , since the pressure-applying member that applies pressure to the ball contacts the ball while tracing a two dimensional movement path, the ball can be passed through the spacer holes while rotating. The present inventors discovered that by doing so, excessive force is not applied to the spacer portions when the ball passes through the spacer holes, and therefore there is reduced deformation in the spacer portions.
In addition, the ultrasonic vibrating means may apply ultrasonic vibration with frequencies that are integer multiples of a predetermined frequency to the pressure-applying member from two axial directions to cause the ball to pass through the spacer holes while rotating in a predetermined direction.
By doing so, the direction of movement of the pressure-applying member at the instant when the pressure-applying member contacts the ball is set at a predetermined direction, and therefore the ball can be passed through the spacer holes while rotating in a predetermined direction. The present inventors discovered that by doing so, it is possible to further avoid having an excessive force applied to the spacer portions when the ball passes through the spacer holes and therefore deformation of the spacer portions is reduced.
In addition, the movement path of the pressure-applying member due to the ultrasonic vibration produced by the ultrasonic vibrating means may be one of a circle and an oval.
By doing so, it is possible to use a simple construction that sets the frequencies of the ultrasonic vibration applied from the two axial directions equally.
The ultrasonic vibrating means may apply ultrasonic vibration to the pressure-applying member from two axial directions that are a pressing direction for the ball and a direction perpendicular to the pressing direction to cause the pressure-applying member to vibrate with a movement path on a plane parallel to the pressing direction and cause the ball to rotate about a rotational axis that is substantially perpendicular to the pressing direction.
By doing so, it is possible to cause the ball to rotate about a rotational axis that is substantially perpendicular to the pressing direction. The present inventors discovered that by doing so, it is possible to further avoid having an excessive force applied to the spacer portions when the ball passes through the spacer holes and therefore deformation of the spacer portions is reduced.
With the method of assembling a cartridge assembly and assembling apparatus according to the present invention, it is possible to suppress deformation in the spacer portions of suspensions and therefore keep the spacer portions flat, which makes it possible to attach suspensions to the carriage arms without tilting and with higher accuracy than the conventional art. By doing so, it is possible to suppress fluctuations in the float characteristics of magnetic heads and therefore it is possible to assemble a carriage assembly with favorable information read/write characteristics.
BRIEF DESCRIPTION OF THE DRAWINGS
The aforementioned and other objects and advantages of the present invention will become apparent to those skilled in the art upon reading an understanding the following detailed description with reference to the accompanying drawings.
In the drawings:
FIG. 1 is a diagram useful in explaining a method of assembling a carriage assembly and an assembling apparatus according to the present invention;
FIG. 2 is a graph showing one example of a movement path of an ultrasonic horn (pressure-applying member);
FIG. 3 is a view showing the appearance of a carriage assembly;
FIG. 4 is a diagram useful in explaining the action that crimps and fixes suspensions to carriage arms by passing a metal ball (ball) through spacer holes of the suspensions;
FIG. 5 is a diagram useful in explaining a conventional method of assembling a carriage assembly; and
FIG. 6 is a diagram useful in explaining a conventional method of assembling a carriage assembly.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The carriage assembly to be assembled by the method of assembling a carriage assembly and assembling apparatus according to an embodiment of the present invention is shown in FIG. 3 . The overall construction of the carriage assembly shown in FIG. 3 has been described for the conventional art, and therefore description thereof is omitted here.
FIG. 1 is a diagram useful in explaining the method of assembling a carriage assembly and assembling apparatus according to the present embodiment. In FIG. 1 , the carriage arms 10 and the suspensions 12 have the same forms as in the conventional art described earlier. That is, the fitting holes 10 a are provided in the front ends of the carriage arms 10 and the spacer holes 12 b to be fitted into the fitting holes 10 a are provided in the spacer portions 12 a provided at the base portions of the suspensions 12 .
The assembling apparatus A for a carriage assembly that uses the method of assembling a carriage assembly according to the present embodiment includes an ultrasonic horn 40 , a first ultrasonic vibrating device 42 and a second ultrasonic vibrating device 44 as ultrasonic vibrating means that apply ultrasonic vibration to the ultrasonic horn 40 , and a driving device 46 capable of moving and controlling the ultrasonic horn 40 so that the ultrasonic horn 40 presses the metal ball 20 to pass the metal ball 20 through . the spacer holes 12 b.
The ultrasonic horn 40 is cylindrical in form and is provided so as to be capable of being coaxially inserted through the spacer holes 12 b , can transmit ultrasonic vibration produced by the first and second ultrasonic vibrating devices 42 , 44 and functions as a pressure-applying member that presses the metal ball 20 to pass the metal ball 20 through the spacer holes 12 b.
It should be noted that the metal ball 20 is formed with a slightly larger diameter than the inner diameter of the spacer holes 12 b.
The first ultrasonic vibrating device 42 applies ultrasonic vibration to the ultrasonic horn 40 in the pressing direction of the metal ball 20 (that is, the axial direction of the spacer holes 12 b ). The second ultrasonic vibrating device 44 applies ultrasonic vibration to the ultrasonic horn 40 in a direction perpendicular to the pressing direction.
That is, ultrasonic vibration is applied to the ultrasonic horn 40 by the first ultrasonic vibrating device 42 and the second ultrasonic vibrating device 44 in two directions that are the pressing direction and the direction perpendicular to the pressing direction. By doing so, the ultrasonic horn 40 is caused to vibrate on a movement path on a plane that is parallel to the pressing direction.
FIG. 2 shows an example of the movement path of the ultrasonic horn 40 . In FIG. 2 , the horizontal axis (X axis) shows the displacement of the ultrasonic horn 40 in the pressing direction and the vertical axis (Y axis) shows the displacement of the ultrasonic horn 40 in the direction perpendicular to the pressing direction (i.e., the up down direction in FIG. 1 ). That is, the amplitude of the ultrasonic horn 40 due to the first ultrasonic vibrating device 42 is expressed by the horizontal axis (X axis) in FIG. 2 and the amplitude due to the second ultrasonic vibrating device 44 is expressed by the vertical axis (Y axis).
In the example shown in FIG. 2 , when the ranges of the displacements of the ultrasonic vibration due to the first ultrasonic vibrating device 42 and the second ultrasonic vibrating device 44 are expressed as −1 to 1 (i.e., the respective amplitudes are 2), the displacements in the X axis and the Y axis of the ultrasonic horn 40 are expressed by the equations X=sin(2πft), Y=cos(2πft) (where f is the frequency (in Hz) of the ultrasonic vibration and t is elapsed time (in seconds)).
By doing so, as shown by the arrow in FIG. 1 and by FIG. 2 , the ultrasonic horn 40 is caused to vibrate on a circular movement path on a plane that is parallel to the pressing direction.
Next, the method of assembling a carriage assembly according to the present embodiment that uses the assembling apparatus A for a carriage assembly will be described.
FIG. 1 shows an operation where the assembling apparatus A for a carriage assembly is used to pass the metal ball 20 through the spacer holes 12 b , of the suspensions 12 to crimp and fix the suspensions 12 to the carriage arms 10 .
As shown in FIG. 1 , in the method of assembling a carriage assembly according to the present embodiment, the suspensions 12 are placed on both surfaces of the respective carriage arms 10 so that the spacer holes 12 b , and the fitting holes 10 a are aligned. In addition, gap maintaining plates 36 are inserted between adjacent carriage arms 10 and pressure-applying plates 37 a , 37 b are placed in contact with both end surfaces of the carriage arms 10 so that the carriage arms 10 are sandwiched from both sides.
In this state, the assembling apparatus A for a carriage assembly is used to pass the metal ball 20 through the spacer holes 12 b . That is, first the metal ball 20 is aligned with the spacer holes 12 b , and the ultrasonic horn 40 is moved by the driving device 46 so as to contact the metal ball 20 and to press in the metal ball 20 so that the metal ball 20 is passed through the spacer holes 12 b . When doing so, the first and second ultrasonic vibrating devices 42 , 44 are driven to apply ultrasonic vibration to the ultrasonic horn 40 from the two axial directions mentioned above.
Since the metal ball 20 is formed with a slightly larger diameter than the spacer holes 12 b , when the metal ball 20 passes through the spacer holes 12 b , the metal ball 20 acts so as to press open the crimping portions 13 formed at the inner circumferential edges of the spacer holes 12 b , and as a result, the suspensions 12 are fixed so as to bite into the carriage arms 10 . As shown in FIGS. 1 and 4 , the metal ball 20 is caused by the ultrasonic horn 40 to move through the successive spacer holes 12 b , from one side of the carriage arms 10 to the other in a single crimping operation.
When doing so, as described above, the ultrasonic horn 40 is caused to vibrate on a circular movement path on a plane that is parallel to the pressing direction. As a result, the ultrasonic horn 40 moves toward and away from the metal ball 20 and since the ultrasonic horn 40 moves in a predetermined direction at the instant when the ultrasonic horn 40 contacts the metal ball 20 (upward in FIG. 1 ), the metal ball 20 is caused to rotate in a predetermined direction about a rotational axis that is substantially perpendicular to the pressing direction (in FIG. 1 , the metal ball 20 is caused to rotate counterclockwise as shown by the arrow).
In the conventional method of assembling a carriage assembly, the metal ball is pressed by a pressure-applying member (ultrasonic horn) that vibrates only in the pressing direction (the axial direction of the spacer holes), and therefore the metal ball hardly rotates. However, in the method of assembling a carriage assembly according to the present embodiment, the pressure-applying member (the ultrasonic horn 40 ) that presses the metal ball 20 contacts the metal ball 20 while tracing a two dimensional movement path, and therefore it is possible to cause the metal ball 20 to pass through the spacer holes 12 b , while rotating.
The present inventors found that by doing so, excessive force is not applied to the spacer portions 12 a when the metal ball 20 passes through the spacer holes 12 b , and therefore there is reduced deformation in the spacer portions 12 a.
Note that the present inventors suppose that the reason for this is that while static friction is produced between the metal ball 20 and the crimping portions 13 with the conventional method, with the method according to the present embodiment, a dynamic friction that is smaller than the static friction acts between the metal ball 20 and the crimping portions 13 due to the metal ball 20 rotating.
With the method of assembling a carriage assembly and the assembling apparatus according to the present embodiment, since deformation of the spacer portions 12 a of the suspensions 12 is suppressed and the spacer portions 12 a are kept flat, the suspensions 12 can be attached to the carriage arms 10 without tilting and with higher accuracy than the conventional art. By doing so, it is possible to suppress fluctuations in the float characteristics of the magnetic heads and therefore it is possible to assemble a carriage assembly with favorable information read/write characteristics.
In particular, by applying ultrasonic vibration of frequencies that are different integer multiples of a predetermined frequency from the two axial directions, the direction of movement of the ultrasonic horn 40 at the instant when the ultrasonic horn 40 contacts the metal ball 20 can be set at a predetermined direction, and therefore the metal ball 20 can be caused to rotate in a “predetermined direction” (that is, a predetermined direction of rotation).
The present inventors discovered that by passing the metal ball 20 through the spacer holes 12 b , while causing the metal ball 20 to rotate in a predetermined direction, it is possible to avoid having an excessive force applied to the spacer portions 12 a when the metal ball 20 passes through the spacer holes 12 b , and therefore deformation of the spacer portions 12 a is reduced.
It should be noted that in the present embodiment, as should be clear from the f value being the same in the equations expressing the displacements of the ultrasonic horn 40 in the two axial directions, the frequencies of the ultrasonic vibration applied from the two axial directions are equal. However, the present invention is not limited to this and may be constructed so that the ultrasonic vibration is applied in the two axial directions with frequencies that are different integer multiples of a predetermined frequency. For example, the frequency F of the ultrasonic vibration applied in the Y axis direction may be set at double the frequency f of the ultrasonic vibration applied in the X axis direction (i.e., F=2f) and the displacement due to the respective ultrasonic vibrations may be set so as to be expressed by the equations X=sin(2πft) and Y=cos(2πFt). By doing so, since it is possible to set the direction of movement of the ultrasonic horn 40 at a predetermined direction when the ultrasonic horn 40 contacts the metal ball 20 , it is possible to cause the metal ball 20 to rotate in a “predetermined direction” (that is, a predetermined direction of rotation).
It is also possible to set the amplitude of the ultrasonic vibration in the X axis direction and the amplitude of the ultrasonic vibration in the Y axis direction differently, that is, to set the respective equations at X=A·sin(2πft) and Y=B·cos(2πft)(where the values A and B are constants such that A≠B) for example, so that the movement path of the ultrasonic horn 40 becomes oval.
Also, although the present embodiment is constructed so that ultrasonic vibration is applied to the ultrasonic horn 40 from two axial directions that are the pressing direction for the metal ball 20 and a direction perpendicular to the pressing direction, the two axial directions for the present invention are not limited to such. For example, if the two axial directions are set as directions that are both perpendicular to the pressing direction and are perpendicular to each other, it is possible to cause the ultrasonic horn 40 to move on a movement path on a plane perpendicular to the pressing direction and to cause the metal ball 20 to rotate about a rotational axis that is parallel to the pressing direction. | A method of assembling a carriage assembly is capable of suppressing deformation of spacer portions when suspensions are attached to carriage arms. The method of assembling a carriage assembly aligns fitting holes provided in front end portions of carriage arms and spacer holes provided in spacer portions of suspensions and places the suspensions onto the carriage arms, and then presses a ball with a diameter equal to or greater than an inner diameter of the spacer holes with a pressure-applying member to pass the ball through the spacer holes, thereby crimping spacer hole edge portions of the spacer portions and attaching the suspensions to the front end portions of the carriage arms. By applying ultrasonic vibration from two axial directions to the pressure-applying member, the pressure-applying member is caused to vibrate on a two-dimensional movement path on a predetermined plane and passes the ball through the spacer holes while causing the ball to rotate. | 8 |
RELATED APPLICATION
[0001] This application claims the benefit of U.S. Pat. Appn. Ser. No. 61/377,455, filed Aug. 26, 2010, having the same title and same assignee as the present application, and is incorporated herein by reference in its entirety. In addition, this application claims the benefit of U.S. patent application Ser. No. 11/694,747, filed Mar. 30, 2007; Ser. No. 11/694,881, filed Mar. 30, 2007; Ser. No. 11/694,906, filed Mar. 30, 2007; Ser. No. 11/694,903, filed Mar. 30, 2007; Ser. No. 11/694,887, filed Mar. 30, 2007; Ser. No. 11/694,894, filed Mar. 30, 2007; Ser. No. 11/694,895, filed Mar. 30, 2007; Ser. No. 11/694,896, filed Mar. 30, 2007; Ser. No. 11/694,891, filed Mar. 30, 2007; and Ser. No. 12/470,482, filed May 21, 2009; and, through them, U.S. patent applications 60/744,013, filed Mar. 30, 2006; 60/744,930, filed Apr. 15, 2006; and 60/870,484, filed Dec. 18, 2006, In addition, this application claims the benefit of U.S. patent application Ser. No. 12/405,203, filed Mar. 16, 2009, patent application Ser. No. 12/555,772, filed Sep. 8, 2009; patent application Ser. No. 13/167,622, filed Jun. 23, 2011; patent application Ser. No. 13/219,304; as well as provisional application Ser. Nos. 60/036,866, filed Mar. 14, 2008; 61/060,118, filed Jun. 9, 2008; Ser. No. 61/095,290, filed Sep. 8, 2008; Ser. No. 61/095,292, filed Sep. 8, 2008; Ser. No. 61/357,949, filed Jun. 23, 2010, and Ser. No. 61/377,455, filed Aug. 26, 2010. All of the foregoing applications are incorporated herein by reference along with all other references cited in this application.
FIELD OF THE INVENTION
[0002] The present invention relates generally to methods and techniques for managing value transfers from a sender to a recipient, and more particularly relates to such methods and techniques where the value exchange can be a donation, payment or other transfer where the nature of the transfer and the recipient are readily entered from a mobile device using either a code character string or a command character string. The code character string can include various default attributes including commands and identification of a recipient. A command string can include various default attributes. The defaults can be modified by the user as desired for a particular transaction. The Sender may chose a variety of funding sources to fund the transaction, while the recipient can receive the funds on a debit or credit account, or immediately in a demand deposit account of their choice. In one embodiment of the present invention the system is used to pay for purchases of goods and services. In another embodiment of the present invention, the system is use to provide donations to charities.
BACKGROUND OF THE INVENTION
[0003] Increasingly consumers are receptive to using mobile phones to conduct financial transactions. This was well demonstrated during several recent humanitarian crises where charities such as the American Red Cross were able to collect funds through mobile messaging. However the solutions in place have a number of drawbacks. First they are limited either to carrier billing, that is funds provided to the recipients are applied to a mobile bill or are required to first become part of a closed loop system such as PayPal, neither of which is desirable for the majority of consumers. Second these solution require establishing SMS short codes for every campaign which is time consuming process only offered by few providers. Third, current solutions only allow for fixed amounts, $5 or $10 for instance. Lastly current solutions result in funds being withheld from the recipient for extended periods of time (up to 45 days or more for carrier billing and in excess of a week for a typical closed loop system) as service providers wait for the phone bill or closed loop account to be settled. Lastly the receiving entities presently do not have access to Sender information which impacts their ability to market and develop their activity. What is therefore needed to deliver a solution viable for the growing number of consumers willing to complete financial transactions on a mobile phone is a solution that provides access to a broader range of recipients, for any sender-selected amount, with access to multiple funding sources for the sender, and rapid transfer of the funds. Once in place such a solution can be used not only to donate money, but also to pay for goods and services from large and small merchants. This solution must be accessible to a broad range of cell phones and subscribers, simple to utilize, yet secure and auditable. This solution must also provide unique means for identifying and reaching Senders. Because the amounts involved may be small it also must be cost efficient. While PayPal has provided elements of a solution in the past, it is neither immediate nor open to any sender without prior registration. Hence a solution that is accessible to all mobile subscribers regardless of their participation to a specific payment scheme is still needed and such a solution must be able to connect to a wide range of payment networks to ensure rapid, safe and convenient processing of transactions from and to a variety of accounts. Accordingly, the following embodiments and exemplary descriptions of the present invention are disclosed.
SUMMARY OF THE INVENTION
[0004] The present invention provides a system and method for managing forms of electronic value exchange, where the value exchange can be a donation, payment or other transfer. The value exchange can be readily initiated from a mobile device using either a code character string or a command character string, and allows the nature of the transfer and the recipient to be readily entered from such a mobile device.
[0005] In an embodiment, the code character string includes various default attributes including commands and identification of a recipient. A command string can include various default attributes. The defaults can be modified by the user as desired for a particular transaction. A variety of funding sources can be selected by the sender to fund the transaction.
BRIEF DESCRIPTION OF THE FIGURES
[0006] FIG. 1 describes a payment processing platform enabling connectivity across different networks and the management of mobile payment transactions.
[0007] FIG. 2 describes an embodiment of the topology of the overall solution of the present invention, and the relationship of the various parties, including such participants as the mobile operators and financial institutions.
[0008] FIG. 3 illustrates a functional implementation of an embodiment of the system of the present invention
[0009] FIG. 4 illustrates an embodiment of a process for servicing a payment request in accordance with the present invention.
[0010] FIG. 5 describes an exemplary embodiment of the overall set of activities from the various participants starting with the registration of a transaction program and ending with a transaction fully completed and funds transferred.
[0011] FIG. 6 Describes an exemplary logical flow governing a transaction starting from a consumer's decision to send money to a recipient and ending with the successful or unsuccessful processing of the transaction
[0012] FIG. 7 details the steps associated with sending, receiving and processing an exemplary SMS command to initiate a transaction.
[0013] FIG. 8 details the steps associated with processing an exemplary checkout in the event of a non-registered user, or an undefined amount.
[0014] FIG. 9 shows an exemplary embodiment of the mobile phone messages for a registered user.
[0015] FIG. 10 shows an exemplary embodiment of the mobile phone messages and initiation of a checkout page for a non-registered user.
[0016] FIG. 11 shows an exemplary embodiment of the checkout procedure for mobile web or mobile application cases.
DETAILED DESCRIPTION OF THE INVENTION
[0017] Referring first to FIGS. 1 and 2 , the present invention comprises, in one aspect, a message-processing platform for enabling the sending, receipt and handling of payment and associated commands, and in another aspect an electronic payment platform and service that provides a fast, easy way for users of mobile and other networked devices to conduct electronic financial transactions between and among clients and servers that are connected to a wireless network. Thus, with particular reference to FIG. 2 , the present invention enables Senders 200 using a messaging device 205 to send orders for payments and money transfers (and associated activities) to charities, merchants, institutions, individuals, or anyone else, substantially anywhere, anytime and on a real time basis via a payment service provider platform 210 . In at least some embodiments, the funds are ‘good’ funds, meaning that those funds, once received, are immediately accessible by the recipient without limitation due to any pending settlement processes. In some embodiments of the present invention only the sender of the funds transferred as part of a transaction need to be registered on the platform. The platform interfaces with mobile devices through a mobile network 215 employing any suitable communications services as SMS, email, IVR, IM, web, etc., shown generally at 215 , and using programming platforms including but not limited to J2ME and Brew, together with network/transport layer protocols including but not limited to WAP, USSD and IP. Smartphones and other similar devices 220 can communicate with the platform 210 directly over the internet 225 .
[0018] In an embodiment, the electronic payment platform of the invention is comprised of a plurality of software modules operating on a plurality of servers accessible through secure network connections and protected from intrusion with any suitable methods such as firewalls, user and machine authentication, and data encryption. In one embodiment of the present invention the electronic payment platform includes a transaction gateway, receiving and posting for processing on a real time basis transactions from mobile networks or SMS aggregators. The electronic payment platform includes appropriate software modules as required to complete Sender registration and management, Receiving entities registrations, transaction management, fraud management, compliance management, network and service level management, customer service management, settlement management, and financial networks connectors management. Financial networks supported include but are not limited to ATM networks 230 , Automatic Clearing House (ACH) connections 235 , and direct secure integration 240 into the hosts of participating financial institutions 245 , whereby a recipient 250 receives the transmitted funds or other value exchange. The electronic payment platform can be implemented on a single server or a plurality of servers located in a single location or geographically dispersed.
[0019] In an embodiment, the system of the present invention is comprised of a series of functional modules for processing a payment-related command received over a messaging interface, and processing the associated payment transaction.
[0020] In an embodiment, the Sender uses a wireless or wired device able to connect through a messaging interface to a point of access defined by an electronic payment service provider. The messaging system is substantially real time and can operate over any suitable platforms such as SMS, MMS, Instant Messaging or Peer-to-Peer messaging. The point of access is defined by a specific address characteristic of the messaging system used, such as a phone number, a short code or an instant messaging id.
[0021] Thus, still referring to FIGS. 1 and 2 , FIG. 1 shows a block diagram of an embodiment of a system for conducting value exchange transactions including in specific implementations, mobile person-to-person payments and transactions, mobile person-to-merchant payment transactions, and mobile banking. An applications server 107 is connected to a network 109 . Although only one applications server is shown, there can be any number of applications servers in a system of the invention. Such applications servers can be executing on a single server machine or a number of server machines, which can be co-located or distributed geographically, including across various institutions.
[0022] A merchant interface 112 and a customer interface 116 are also connected to the network. This network can be any network that carries data including, but not limited to, the Internet, private networks, or virtual private networks, transported over such connections as enabled by public switch telephone network (PSTN), ISDN, DSL, wireless data networks, and many others, and combinations of these. The customer interface can handle any number of customers. The merchant interface is also connected to the applications server. Similar to the customer interface, there can be any number of merchants that connect to the application server.
[0023] On the applications server is a payment processor 119 , which can also be connected to the merchant interface. A financial institution interface 123 is connected to the applications server and payment processor. There can be any number of financial institutions connected to the applications server. The applications server can also include a database 127 . The database can include a system of record (SOR) 130 and virtual pooled accounts 134 , which the applications server can manage. Alternatively, the SOR database can be on a separate server from the applications server and accessible to the applications server through a network or other connection. The financial institution is also connected to the database. The financial institution can manage pooled accounts 138 . Therefore the system of record and virtual pooled accounts can be managed separately from the pooled accounts at the financial institution.
[0024] In an embodiment, the system of record 130 comprises functionality for maintaining real time debit, credit, history and balance for the account of each user of the system, whether merchant, individual, financial institution, etc. The SOR database can comprise a ledger account, or “T” account, for each user to facilitate tracking that user's transactions. In some embodiments, the SOR 130 also maintains a record of each user's “know your customer” (KYC) and OFAC information, together with any other appropriate identifying information. In some embodiments the SOR 130 can also include anti-fraud and security data, including velocity related data. It will be appreciated by those skilled in the art that the partial or duplicate SOR's can be maintained at the servers of various entities within the network, to provide appropriate aspects of debit, credit, history and balance information as required for that particular entity's needs. In some embodiments, the system operator is an account aggregator and becomes the system of record in terms of risk and risk control. The system operator is also responsible for performing the OFAC compliance check. The system operator can be a bank, a financial institution, an association, or can subcontract the account management to another bank.
[0025] A system of the invention can include any number of the elements shown in the figure. The system can include other elements not shown. Some elements can be divided into separate blocks, or some elements can be incorporated or combined with other elements. Additionally, some elements can be substituted with other elements not shown.
[0026] As can be better appreciated from FIGS. 3-5 , the Sender 300 ( FIG. 3 ) uses the messaging interface to send a command string with payment or payment related instructions to the electronic payment processing service provider via a service point of access using a common entry address 305 , as indicated in process flow form at step 400 of FIG. 4 . The command string can include a command word and, optionally, one or more associated command attributes together with a recipient indicia or code word. The command word is defined by the Electronic Payment Processing Service provider and can be any actual word, abbreviation, or character string, in English or other languages. In some embodiments, a plurality of command words can be defined to result in the same electronic payment transaction. Command words can have command attributes. Command attributes can include such parameters as, for example, the amount to pay/transfer, or a time delay before executing the transfer, or the frequency of a plurality of transfers, or a message to append to the transaction log. A command can be configured to have default or implicit attributes. For instance “Donate HaitiOutreach” may be programmed with attributes that cause it to be processed by the payment platform exactly the same as a command string saying “Donate $10 to HaitiOutreach”. In an embodiment, code words are selected and determined by Recipients and registered with the electronic payment processing service, as shown at step 500 of FIG. 5 , although in other embodiments the payment processing service may provide a code word. Code words can comprise a word, a phrase, or other character string. Code words can have associated with them implicit or default command words and command attributes. For instance “MetroPCS” on its own could be defined to mean “Pay $40 to MetroPCS”. In at least some embodiments, a Sender is permitted to override implicit commands and attributes to execute different commands and functions. In an embodiment, a command string comprises a command word, followed optionally by a first separator and command attributes, followed by a second separator, followed by a code word, as shown below:
[Command Word][1 st Separator][Command Attribute][1 st Separator] . . . [2 nd Separator][Code Word]
[0027] In some embodiments any number of command attributes can be included in the command string. The first separator can be a special character such as a comma, space, column, or other suitable placeholder. The second character can be a special character or a reserved word such as “to” or other suitable string.
[0028] Referring still to FIGS. 3-5 , an exemplary embodiment of one arrangement of the invention in described. The Sender connects with his/her messaging interface to the service point of access, using a common entry address provided by the electronic payment service provider, as shown at step 400 of FIG. 4 and step 510 of FIG. 5 . The command message entered into the messaging interface by the Sender is parsed and processed by the code word and command dispatchers 310 and 315 , which interpret the command and code word and any associated command attributes according to a code word map 320 and command word map 325 included in the system of the present invention, as shown at steps 405 - 420 of FIG. 4 . The code word map and command map may be accessed by system administration tools as required to on-board (or enroll or register) new recipients, register new code words, create new commands and generally administer transactions.
[0029] The command processor 330 executes the command as interpreted by the command dispatcher and code word dispatcher, as indicated at step 425 of FIG. 4 . Command processing can include a message in response to the command string from the Sender. Example of response messages can include a confirmation of the transaction, a confirmation request for the order to perform the transaction, information about past transactions, information about recipients, or information about specific recipient programs.
[0030] Message responses from the command processor to the sender are processed and sent by the notification processor 335 when invoked by the command processor.
[0031] The command processor transfers the processing of the transaction to the transaction processor 340 . The transaction processor verifies the eligibility of the user and the validity of the transaction. To the extent required by the transaction, the transaction processor may invoke the notification processor to message to the Sender, as indicated at step 430 of FIG. 4 . Instances of messages to the Sender include transaction information or transaction confirmations, shown at FIG. 4 , step 440 . The transaction processor may require additional information from the Sender—for instance in the case of a unregistered user, as indicated generally at step 515 of FIG. 5 . In such a case the transaction processor directs the Sender to a checkout process as follows. The Sender executes a checkout of the sort generally indicated at step 520 of FIG. 5 by connecting to the Unique checkout address 345 ( FIG. 3 ) provided by the transaction processor in its response message. The checkout address can refer to a web page, a mobile web page, a wap page, an IVR number, or a specific client mobile app, and is used to connect the Sender to, and interface with, a registration and checkout processor 350 .
[0032] The registration and checkout processor 350 performs such additional tasks as may be required to complete the transaction, such as the registration of a user, the registration of a new funding source, as indicated at 355 , or simply information such as amounts of the transaction and authentication codes for accessing an existing funding source 360 , in the process indicated at steps 440 - 455 of FIG. 4 . Authentication codes can include PIN codes, passwords and pass phrases, security codes. Upon completion of the Registration and Checkout, the transaction processor is able to complete the transaction processing, including maintaining appropriate data stores 365 and 370 , and maps the transaction steps to the appropriate transaction systems using a system dispatcher 375 and associated data store indicated as system map 380 , as shown at step 460 of FIG. 4 . The results of the system dispatch are provided to an electronic payment system 385 as described previously, and the funds or other forms of value are electronically “disbursed” to a receiving account 390 associated with the receiving entity 395 , as shown at step 470 of FIG. 4 . The result is that the service provider settles the transaction with the sender's and recipient's financial institution as indicated at step 525 of FIG. 5 . In at least some embodiments the settlement is substantially in real time, as discussed previously. The output can also be provided to any other appropriate system, indicated at 397
[0033] The operation of the present invention from the perspective of the payment platform can be better appreciated from FIG. 6 . As shown at step 600 , a payer initiates a transaction by sending an instruction via SMS or other suitable platform to the payment service provider (“PSP”). The instruction comprises, in essence, a “pay” command, an amount, and a recipient. The recipient is, in at least some embodiments, indicated by a code word. The PSP verifies the pay command as shown at step 605 . If the pay command is incorrect, an error message is generated as shown at step 610 . However, if the pay command is correct, the process advances to step 615 , where the PSP verifies the code word that identifies at least the recipient and, in some embodiments, also identifies various default attributes such as amount, funding destination, or other data appropriate to the transaction.
[0034] If the code word is incorrect in that it does not identify a recipient, an error message is generated as shown at step 620 . If the code word is correct, the process advances to step 625 and verifies the payer and the amount. If the payer is registered and the amount is valid, a confirmation message, including in some embodiments a confirmation code, is generated and sent to the sender, as shown at step 630 . If the payer is not registered, or the amount is invalid, the PSP sends a confirmation message seeking appropriate action by the sender as shown at step 635 .
[0035] Depending on the action required by the confirmation message, the payer executes the confirmation action, such as by identifying the source of funds, the payment amount, or other information needed to complete the transaction, all as shown at step 640 . The PSP then processes the transaction including fraud management review, verification of funds availability, and any additional verification of the payer as appropriate to the transaction. If the transaction then completes successfully, the PSP settles the transaction by depositing funds into the recipient's account, as shown at step 650 . If the transaction did not complete successfully, an appropriate message is generated as shown at step 655 .
[0036] It will be appreciated by those skilled in the art that the invention, including the transaction processor, is capable of processing financial and non financial transactions. Examples of non financial value exchange transactions include the transfer of loyalty points to a third party, for instance for charity purposes. In as much as the execution of a transaction must be split between different processing systems, the transaction processor invokes a system dispatcher as shown in FIG. 3 , which routes transactions to the appropriate transaction processing systems.
[0037] One such transaction processing system is the electronic payment platform described as part of the present invention.
[0038] The following describes an embodiment of the system of the present invention used for transferring funds for the purpose of a charitable donation.
[0039] Financial transactions can be conducted by individuals registered or not, interacting with entities having registered an account with the electronic payment service provider. Registered sending individuals are identified by their phone numbers, or financial account while registered receiving entities are identified by a unique code word of their choice. Receiving entities may be any of individuals, merchants, charitable institutions.
[0040] In one embodiment registered senders may maintain one or a plurality of funding accounts any one or more of which they may use to fund a transaction. Funding accounts can be held with the electronic payment service provider in the form of a prepaid account, or with third party financial services providers. Accounts can include checking accounts, credit accounts, debit accounts and prepaid accounts whether in a private currency or not. When the user desires to conduct a transaction the account are accessed by the electronic payment service provider to validate funds availability and to conduct settlement with the account holding institution of the receiver.
[0041] In one embodiment unregistered users may use the system by entering their chosen funding account references during the checkout process.
[0042] In at least some implementations of the invention, in order to receive funds with the electronic payment processing service where the sender identifies the recipient by a code word, receiving entities must register with the electronic payment processing service provider. In an embodiment, registration requires that the recipient provide information sufficient to identify at least one account into which transaction funds can be deposited, such as a demand deposit account, a debit account or a prepaid debit account. Alternatively the receiving entity may sign up for a prepaid debit account with the electronic payment service provider. Registration further requires that the receiving entity submits to the necessary checks for Fraud Management purposes and compliance with the financial regulations in place (such as Anti Money Laundering). At registration, the receiving organization also chooses one or a plurality of Code Words, that Senders may utilize to identify the receiving entity as the recipient of funds in a transaction. In one embodiment of this invention the receiving entity may be a person and the Code Word may be a mobile phone number or email. In at least some embodiments, the code words uniquely identify a recipient, although the code word(s) need not be unique to a particular campaign in all instances.
[0043] In one embodiment of the present information Receiving parties may also provide to the Electronic Payment Processing service providers additional information on themselves, or on the program associated to the transaction to respond to queries by the Senders. Receiving parties also may determine the processing terms for the transaction and in particular whether they wish to receive funds immediately.
[0044] Receiving entities are then able to provide the Senders with the Code Word to use in a transaction. This can be done via a variety of communication methods such as mail, email, print media, display media, Video or Audio advertising. In one embodiment of the present invention the Receiving entity may display its Code Word at the location and point where it provides services to a Sender which then uses its mobile phone and the electronic payment processing service to provide payments to the Receiving entity at the time the Sender receives services. A unique aspect of the present invention is the ability of the Electronic Payment Processing service to receive a transaction, process a payment and deposit funds into the account of the Receiving entity in real time, thus enabling commercial transactions. Through the use of such an arrangement, the present invention is superior to other existing solutions where receiving entities must obtain a short code from a mobile operator or an intermediary, a complex, lengthy and expensive process. In addition Receiving entities may utilize a plurality of Code Words targeted for use by different Senders, or different occasions, thus multiplying the marketing and data mining opportunities offered by the system of the present invention.
[0045] Equipped with the knowledge of the Code Word of the intended receiving entity of a transaction, the Sender is able to send any amounts of money to the receiving party, subject to such limits as may be required for fraud prevention or currency transfer rules. This is accomplished by the Sender sending to the Electronic Payment Processing service provider a short message with a command word and command attributes, and code word, such as shown at 700 in FIG. 7 . Exemplary embodiments of Command Word would be “Pay” or “Donate” or “Transfer” or “Send_Money” or “Cash”. The amount may be any sum defined by the Sender. In addition in one embodiment of the present invention the Command Word may be refer to specific or default Amount. For instance “DonateNow HaitiRelief” may have the same meaning as “Pay $25 HaitiRelief, where HaitiRelief” is the Code Word of the receiving entity. In yet another embodiment of the present invention a Command Word may be explicitly created for a program and linked to a particular receiving organization. For instance “DonateHaiti” may have the same significance as “Pay now $19 to Haitioutreach”. The system of the present invention is thus superior to pre-existing solution in that it allows a variety of command words to be defined and concurrently supported and that any amounts may be transacted over the system, rather than only a limited number of pre-determined amounts. Thus the present invention is distinguished from the prior art by, among other things, its ability to allow recipients to define and execute evolved campaigns.
[0046] As illustrated in FIG. 7 , the keyword is checked at step 705 by the system of the present invention, which also checks the remaining steps in the process. If the keyword is not active with a recipient, an error message is sent as shown at step 715 . However, if the keyword is valid, the process advances to step 720 , where the system checks to determine whether the sender is registered. If the sender is registered, then in some embodiments a check is made at 725 to determine whether the financial partner associated with the sender has authorized its customers to participate in the type of transaction requested by the sender.
[0047] If the sender is not registered, as determined at step 720 , the process converts to a request for payment from an unregistered payer, as shown at step 730 and discussed further hereinafter.
[0048] If the financial partner is determined to be compatible as shown at step 735 , then, in some embodiments, a message is generated requesting an IVR callback to provide confirmation or, if no donation or payment amount was specified, to prompt the sender to enter the necessary data. Any suitable confirmation method is acceptable, such as a PIN or other authentication indicia. The sender then executes the confirmation as indicated at step 740 , such that the callback is completed and the sending of funds done as shown at step 745 .
[0049] If the sender is not registered, the indicia used to identify the sender, such as phone number, email address or other identifier, is determined at step 750 . If the phone number is known, a request for the sender email address is sent as shown at steps 755 and 760 . Similarly, if the sender's email address is known, an email request for the sender's phone number is sent, as shown at steps 765 and 770 .
[0050] In one embodiment of the present invention the Electronic Payment Processing platform is capable of processing information commands, providing either information on the service, or information on the intended recipient of the funds (“Haiti Outreach”), or information on the program associated with the transaction (“Haiti-telethon”) or information on previous transactions completed by the Sender.
[0051] Upon receiving an Electronic Payment Processing message, the system of the present invention determines whether the sender is a registered user or not.
[0052] Registered Senders may complete their transaction with a simple confirmation procedure, whereby the Electronic Payment Processing service provider replies to the Electronic Payment Processing message with a Confirmation Code, or, optionally, a Confirmation Link and a request for Sender authentication. The Sender may use the confirmation code in any number of confirmation methods either through the messaging interface used to initiate the transaction or through other methods such as a web page or a mobile app or a call to an IVR/automated voice response system, as designated in the Confirmation Link. The Sender uses the Confirmation Code in the event the Confirmation Method uses a different messaging interface, to avoid a break in the Payment Processing command flow. In one embodiment of the present invention, the sender may also receives the Confirmation Code as part of a request for payment message. The Sender authentication method may comprise one or a plurality of Authentication Methods including something the Sender knows (such as a PIN CODE or PASSWORD), and/or something the Sender owns (such as the serial number or IMIE number or phone number, and/or something the Sender is (such as a biometrics data capture). In one embodiment of the present invention, multiple authentication methods are required to confirm the transaction to ensure high levels of security. Upon confirmation of the identity of the Sender, funds are then debited from the Funding Account defined by the registered Sender and processed by the Electronic Payment Processing service. The present invention is unique compared to existing solutions in that it enables a confirmation of the transaction through a variety of different Sender interfaces, leveraging the most convenient and secure methods required by the Electronic Payment Processing service provider and/or the Receiving entity. Thus transactions are confirmed positively to avoid subsequent disputes. In addition support for multiple methods of authentication of the Sender not only prevents fraud but also enables higher standards of auditability of the transactions.
[0053] Unregistered Senders may complete the transaction by proceeding through a linked checkout process, such as shown in FIG. 8 . The Electronic Payment Processing platform, having determined that the Sender is not registered, responds to the Electronic Payment Processing message with Confirmation Method link and optionally a confirmation code. The Sender is thus directed to a checkout process that will capture his or her funding account, a confirmation of the amount to process, the confirmation code sent by the Electronic Payment Processing platform and any personal information as may be required to confirm the availability of funds with the entity holding the funding account of the Sender. Upon validation of the funding information of the Sender, the Electronic Payment transaction is processed by the Electronic Payment Processing platforms. Thus the system of the present invention is superior to any current solution in that it allows any user—registered or not with the Electronic Payment Processing service provider—to participate to a transaction. Various other verifications can also be performed in at least some embodiments, including limits on the size of a one-time transaction, lifetime limits on the sum of a plurality of transactions. Likewise, multifactor authentication is used in some embodiments. Thus, referring to FIG. 8 , when a sender is referred to checkout, the process begins at 800 . The request is then checked to determine whether the amount exceeds either a one time limit or a lifetime limit on the amount of funds that can be transferred before registration is required, as indicated at steps 805 - 830 . If the request passes the various checks, the payment source is then verified as shown at steps 835 - 850 , where a lockout occurs if authentication fails a plurality of times, such as three failures. Payment is then checked at step 855 and, if no problem is found at step 860 , payment is confirmed at step 870 . If a problem is found, an error message is sent at step 865 .
[0054] An MDN/PIN check is also performed in at least some embodiments, as indicated at step 875 . If the wrong PIN is entered a plurality of times, such as three, or the Multifactor Authentication (MFA) fails, or an overlimit occurs, as checked and indicated at steps 880 A- 885 C, then the transaction fails. However, If each of the checks completes satisfactorily, payment is then verified at shown at step 890 and payment is made at step 895 . A plurality of retries can be permitted if steps 845 or 875 are not completed successfully, as shown by the loop back to step 800 .
[0055] FIGS. 9 , 10 , and 11 illustrate exemplary embodiments of the mobile phone messages and checkout pages for registered and unregistered users. Thus, FIG. 9 shows an embodiment of the messages exchanged with a registered user, whereas FIG. 10 shows an embodiment of phone messages and checkout page for an unregistered user, while FIG. 11 shows an exemplary embodiment of the checkout procedure for mobile web or mobile application cases.
[0056] Registered User may chose to use the linked confirmation/checkout process to select other forms of payment and/or funding accounts as may be designated in their registration. The system of the present invention is therefore distinguished from any current payment platforms as it allows the selection of a plurality of funding source for any given transaction at the discretion of the Sender, in effect increasing the transaction opportunities for the Receiving party.
[0057] In one embodiment of the present invention the Electronic Payment platform sends to the Sender a transaction confirmation message or alternatively a transaction failure message.
[0058] When processing the transaction, the Electronic Payment Processing platform performs a number of functions such as transaction velocity checking as well as user and device authentication, to identify any potential fraudulent transactions, fee processing and collection for the transaction processed. The Electronic Payment Processing platform then settles and clears the transaction generating funds transfer commands to the appropriate financial network depending on the settlement terms of the transaction (real time or delayed). Settlement of the transaction and transfer of the funds processed may be on a real time or delayed basis according to the selection of the Receiving entity and the funding source and method used by the Sender. The system of the present invention by integrating a Payment message module with a payment processing module with a settlement module is distinguished from present solutions by the flexibility it provides to the recipients to select the terms (availability of funds) and costs (transaction service fees) best suited to their needs or the need of a specific program.
[0059] In addition to processing transactions, the Electronic Payment Processing service provider maintains such information as may be needed for the purpose of support Customer Support inquiries, transaction dispute processes in accordance to the rules associated with the funding accounts, and any inquiries required by regulations or compliance programs. A large number of new products and services will benefit from the present invention. For example, any device capable of communicating wirelessly and through a simple message interface with the Electronic Payment Processing service may be used to practice the present invention. Such include devices used in the context of Instant Messaging over wireless protocols.
[0060] It will further be appreciated that one or more of the elements depicted in the drawings or figures can also be implemented in a more separated or integrated manner, or even removed or rendered as inoperable in certain cases, as is useful in accordance with a particular application.
[0061] Although the invention has been described with respect to specific embodiments thereof, these embodiments are merely illustrative, and not restrictive of the invention. For example, further embodiments can include various alternative indicia in lieu of the Code Word, such as unique bar codes scanned by Sender. The cell phone can be any communication device that is portable and capable of connecting to a data network through at least one instant messaging interface and protocol.
[0062] Additionally, any signal arrows in the drawings or figures should be considered as only exemplary, and not limiting, unless otherwise specifically noted. Furthermore, the term “or” as used in this application is generally intended to mean “and/or” unless otherwise indicated. Combinations of components or steps will also be considered as being noted, where terminology is foreseen as rendering the ability to separate or combine is unclear.
[0063] As used in the description in this application and throughout the claims that follow, “a,” “an,” and “the” includes plural references unless the context clearly dictates otherwise. Also, as used in this description and throughout the claims that follow, the meaning of “in” includes “in” and “on” unless the context clearly dictates otherwise.
[0064] This description of the invention has been presented for the purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise form described, and many modifications and variations are possible in light of the teaching above. The embodiments were chosen and described in order to best explain the principles of the invention and its practical applications. This description will enable others skilled in the art to best utilize and practice the invention in various embodiments and with various modifications as are suited to a particular use. The scope of the invention is defined by the following claims. | The present invention relates to a method and system for providing payments over a wireless connection. Instant messaging services—such as mobile text messaging—addressed to a command interpretation and processing system are utilized in conjunction with a checkout procedure on a mobile device to enable a user making a payment to simply define and confirm the amount of his or her payment, and the recipient. The checkout procedure can be completed with SMS, Mobile Web, Mobile App or IVR implementation. Previously Registered as well as new unregistered users are supported. The payer, through his or her mobile device, interacts with a system for managing mobile payment transactions that validates the sender and recipient of the funds, the presence of funds in a transacting account and other fraud management and authentication checks, and effects a settlement. The Sender may chose a variety of funding sources to fund the transaction, while the recipient can receive the funds on a debit or credit account, or immediately in a demand deposit account of their choice. In one embodiment of the present invention the system is used to pay for purchases of goods and services. In another embodiment of the present invention, the system is use to provide donations to charities. | 6 |
This invention was made with United States Government support awarded by the National Institutes of Health (NIH), Grant No. DK-14881. The United States Government has certain rights in this invention.
This application is a divisional of application Ser. No. 08/157,970 filed Nov. 24, 1993, now U.S. Pat. No. 5,373,004.
BACKGROUND OF THE INVENTION
This invention relates to biologically active vitamin D compounds. More specifically, the invention relates to 26,28-Methylene-1α,25-dihydroxyvitamin D 2 compounds, to a general process for their preparation, and to their use in treating osteoporosis.
With the discovery of 1α,25-dihydroxyvitamin D 3 as the active form of the vitamin has come an intense investigation of analogs of this hormonal form of vitamin D with the intent of finding analogs that have selective activity. By now, several compounds have been discovered which carry out the differentiative role of 1,25-dihydroxyvitamin D 3 while having little or no calcium activity. Additionally, other compounds have been found that have minimal activities in the mobilization of calcium from bone while having significant activities in stimulating intestinal calcium transport. Modification of the vitamin D side chain by lengthening it at the 24-carbon has resulted in loss of calcium activity and either an enhancement or undisturbed differentiative activity. Placing the 24-methyl of 1α,25-dihydroxyvitamin D 2 in the epi-configuration appears to diminish activity in the mobilization of calcium from bone. On the other hand, increased hydrophobicity on the 26- and 27-carbons seems to increase the total activity of the vitamin D compounds provided the 25-hydroxyl is present.
Several of these known compounds exhibit highly potent activity in vivo or in vitro, and possess advantageous activity profiles. Thus, they are in use, or have been proposed for use, in the treatment of a variety of diseases such as renal osteodystrophy, vitamin D-resistant rickets, osteoporosis, psoriasis, and certain malignancies.
It is well known that females at the time of menopause suffer a marked loss of bone mass giving rise ultimately to osteopenia, which in turn gives rise to spontaneous crush fractures of the vertebrae and fractures of the long bones. This disease is generally known as postmenopausal osteoporosis and presents a major medical problem, both in the United States and most other countries where the life-span of females reaches ages of at least 60 and 70 years. Generally, the disease which is often accompanied by bone pain and decreased physical activity, is diagnosed by one or two vertebral crush fractures with evidence of diminished bone mass. It is known that this disease is accompanied by diminished ability to absorb calcium, decreased levels of sex hormones, especially estrogen and androgen, and a negative calcium balance.
Similar symptoms of bone loss characterize senile osteoporosis and steroid-induced osteoporosis, the latter being a recognized result of long term glucocorticoid (cortico-steroid) therapy for certain disease states.
Methods for treating the disease have varied considerably but to date no totally satisfactory treatment is yet known. A conventional treatment is to administer a calcium supplement to the patient. However, calcium supplementation by itself has not been successful in preventing or curing the disease. Another conventional treatment is the injection of sex hormones, especially estrogen, which has been reported to be effective in preventing the rapid loss of bone mass experienced in postmenopausal women. This technique, however, has been complicated by the fact of its possible carcinogenicity. Other treatments for which variable results have been reported, have included a combination of vitamin D in large doses, calcium and fluoride. The primary problem with this approach is that fluoride induces structurally unsound bone, called woven bone, and in addition, produces a number of side effects such as increased incidence of fractures and gastrointestinal reaction to the large amounts of fluoride administered. Another suggested method is to block bone resorption by injecting calcitonin or providing phosphonates.
U.S. Pat. No. 4,225,596 suggests the use of various metabolites of vitamin D 3 for increasing calcium absorption and retention within the body of mammals displaying evidence of or having a physiological tendency toward loss of bone mass. The metabolites specifically named in that patent, i.e., 1α-hydroxyvitamin D 3 , 1α-hydroxyvitamin D 2 , 1α,25-dihydroxyvitamin D 3 , 1α,25-dihydroxyvitamin D 2 and 1,24,25-trihydroxyvitamin D 3 , although capable of the activity described and claimed in that patent are also characterized by the disadvantage of causing hypercalcemia especially if used with the conventional calcium supplement treatment. Therefore, use of these compounds to treat osteoporosis has not been widely accepted. U.S. Pat. Nos. 3,833,622 and 3,901,928 respectively suggest using the hydrate of 25-hydroxyvitamin D 3 and 1α-hydroxyvitamin D 3 for treatment of osteoporosis in a general expression of utility for those compounds. It is well known both of those compounds express traditional vitamin D-like activity, including the danger of hypercalcemia.
U.S. Pat. No. 4,588,716 also suggests the use of 1α,25-dihydroxy-24-epi-vitamin D 2 to treat bone disorders characterized by the loss of bone mass, such as osteoporosis. This compound expresses some of the vitamin D-like characteristics affecting calcium metabolism such as increasing intestinal calcium transport and stimulating the mineralization of new bone, but has the advantage of minimal effectiveness in mobilizing calcium from bone. The 24-epi compound may be administered alone or in combination with a bone mobilization-inducing compound such as a hormone or vitamin D compound such as 1α-hydroxyvitamin D 3 or D 2 or 1α,25-dihydroxyvitamin D 3 or D 2 .
U.S. Pat. No. 5,194,431 discloses the use of 24-cyclopropane vitamin D 2 compounds in treating osteoporosis. Also, U.S. Pat. No. 4,851,401 discloses the use of cyclopentano-1,25-dihydroxyvitamin D 3 compounds in the treatment of osteoporosis and related diseases.
SUMMARY OF THE INVENTION
The present invention provides novel compounds exhibiting a desired, and highly advantageous, pattern of biological activity. These compounds are characterized by a marked intestinal calcium transport activity, as compared to that of 1α,25-dihydroxyvitamin D 3 , while exhibiting much lower activity than 1α,25-dihydroxyvitamin D 3 in their ability to mobilize calcium from bone. Hence, these compounds are highly specific in their calcemic activity. Their preferential activity on intestinal calcium transport and reduced calcium mobilizing activity in bone allows the in vivo administration of these compounds for the treatment of metabolic bone diseases where bone loss is a major concern. Because of their preferential calcemic activity, these compounds would be preferred therapeutic agents for the treatment of diseases where bone formation is desired, such as osteoporosis, osteomalacia and renal osteodystrophy.
Structurally, the key feature of the compounds having these desirable biological attributes is that they are analogs of 1,25-dihydroxyvitamin D 2 in which a cyclopentane ring is introduced onto the side chain. Thus, the compounds of this type are characterized by the following general structure: ##STR1##
The present invention, therefore, provides novel compounds showing preferential activity on intestinal calcium transport and reduced calcium mobilizing activity in bone, or high bone calcium mobilizing activity. The reduced bone mobilizing activity would make these compounds especially suitable to treat osteoporosis where bone turnover is high (i.e. postmenopausal type), while the compounds having high bone calcium mobilizing activity would be suitable for low turnover osteoporosis such as age-related osteoporosis. More specifically, the compounds are (22E, 24R, 25R)-26,28-methylene-1α,25-dihydroxyvitamin D 2 ; (22E, 24S, 25S)-26,28-methylene-1α,25-dihydroxyvitamin D 2 ; (22E, 24R, 25S)-26,28-methylene-1α,25-dihydroxyvitamin D 2 ; and (22E, 24S, 25R)-26,28-methylene-1α,25-dihydroxyvitamin D 2 .
This invention also provides novel intermediate compounds formed during the synthesis of the end products. Structurally, the intermediate compounds are characterized by the following general structure: ##STR2## where R1, R2 and R3 may be hydrogen or a hydroxy-protecting group.
In another aspect of the invention, it has now been found that the loss of bone mass, which is characteristic of osteoporosis may be effectively treated by the administration of a 26,28-methylene-1α,25-dihydroxyvitamin D 2 compound in sufficient amounts to increase bone mass. More specifically, a method of treating osteoporosis comprises the administration of an effective mount of any of the above four isomers of 26,28-methylene-1α,25-dihydroxyvitamin D 2 . The above compounds may be administered alone or in combination with other pharmaceutically acceptable agents. Dosages of from not less than about 0.5 μg/day to not more than about 50 μg/day of the individual compound per se, or in combinations, are generally effective. This method has the distinct advantage that it will restore bone mass due to the insignificant bone mobilization activity of this compound and further this compound advantageously will not cause hypercalcemia even if the compound is administered continuously on a daily basis, as long as the appropriate compound dosages are used, it being understood that the dosage levels will be adjusted dependent on the response of the subject as monitored by methods known to those skilled in the art.
The above method, involving the administration of the indicated dosages of any one of the four isomers of 26,28-methylene-1α,25-dihydroxyvitamin D 2 is effective in restoring or maintaining bone mass, and thus provides a novel method for the treatment or prevention of various forms of osteoporosis such as postmenopausal osteoporosis, senile osteoporosis and steroid-induced osteoporosis. It will be evident that the method will also find ready application for the prevention or treatment of disease states other than those named, in which the loss of bone mass is an indication.
DETAILED DESCRIPTION OF THE INVENTION
As used in the description and in the claims, the term hydroxy-protecting group signifies any group commonly used for the temporary protection of hydroxy functions, such as for example, alkoxycarbonyl, acyl, alkylsilyl, alkylarylsilyl, and alkoxyalkyl groups, and a protected hydroxy group is a hydroxy function derivatized by such a protecting group. Alkoxycarbonyl protecting groups are groupings such as methoxycarbonyl, ethoxycarbonyl, propoxycarbonyl, isopropoxycarbonyl, butoxycarbonyl, isobutoxycarbonyl, tert-butoxycarbonyl, benzyloxycarbonyl or allyloxycarbonyl. The term `acyl` signifies an alkanoyl group of 1 to 6 carbons, in all of its isomeric forms, or a carboxyalkanoyl group of 1 to 6 carbons, such as an oxalyl, malonyl, succinyl, glutaryl group, or an aromatic acyl group such as benzoyl, or a halo, nitro or alkyl substituted benzoyl group. The word `alkyl` as used in the description or the claims, denotes a straight-chain or branched hydrocarbon radical of 1 to 10 carbons, in all its isomeric forms. Alkoxyalkyl protecting groups are groupings such as methoxymethyl, ethoxyethyl, methoxyethoxymethyl, or tetrahydrofuranyl and tetrahydropyranyl. Preferred alkylsilyl-protecting groups are trimethylsilyl, triethylsilyl, t-butyldimethylsilyl, and analogous alkylated silyl radicals. Alkylarylsilyl protecting groups are groupings such as tert-butyldiphenylsilyl.
The vitamin D compounds useful in the present treatment are (22E, 24R, 25R)-26,28-methylene-1α,25-dihydroxyvitamin D 2 ; (22E, 24S, 25S)-26,28-methylene-1α,25-dihydrovitamin D 2 ; (22E, 24R, 25S)-26,28-methylene-1α-25-dihydroxyvitamin D 2 ; and (22E, 24S, 25R)-26,28-methylene-1α,25-dihydroxy-vitamin D 2 . The above compounds may be administered alone or in combination with other pharmaceutically acceptable agents.
The vitamin D compounds or combinations thereof can be readily administered as sterile parenteral solutions by injection or intravenously, or by alimentary canal in the form of oral dosages, or trans-dermally, or by suppository. Doses of from about 0.5 micrograms to about 50 micrograms per day of the 26,28-methylene-1α-hydroxyvitamin D 2 compounds per se, or in combination with other 1α-hydroxylated vitamin D compounds, the proportions of each of the compounds in the combination being dependent upon the particular disease state being addressed and the degree of bone mineralization and/or bone mobilization desired, are generally effective to practice the present invention. In all cases sufficient mounts of the compound should be used to restore bone mass. Amounts in excess of about 50 micrograms per day or the combination of that compound with other 1α-hydroxylated vitamin D compounds, are generally unnecessary to achieve the desired results, may result in hypercalcemia, and may not be an economically sound practice. In practice the higher doses are used where therapeutic treatment of a disease state is the desired end while the lower doses are generally used for prophylactic purposes, it being understood that the specific dosage administered in any given case will be adjusted in accordance with the specific compounds being administered, the disease to be treated, the condition of the subject and the other relevant medical facts that may modify the activity of the drug or the response of the subject, as is well known by those skilled in the art. For example, to be effective, the 26,28-methylene-1α,25-dihydroxyvitamin D 2 compounds are preferably administered in a dosage range of 0.5-50 μ/day. In general, either a single daily dose or divided daily dosages may be employed, as is well known in the art.
Dosage forms of the various compounds can be prepared by combining them with non-toxic pharmaceutically acceptable carriers to make either immediate release or slow release formulations, as is well known in the art. Such carriers may be either solid or liquid such as, for example, corn starch, lactose, sucrose, peanut oil, olive oil, sesame oil and propylene glycol. If a solid carrier is used the dosage form of the compounds may be tablets, capsules, powders, troches or lozenges. If a liquid carrier is used, soft gelatin capsules, or syrup or liquid suspensions, emulsions or solutions may be the dosage form. The dosage forms may also contain adjuvants, such as preserving, stabilizing, wetting or emulsifying agents, solution promoters, etc. They may also contain other therapeutically valuable substances.
The present invention is more specifically described by the following examples, which are meant to be illustrative only of the process of synthesis and of the novel compounds, both end products and intermediates, obtainable thereby. In these examples, specific compounds identified by Arabic numerals (e.g. compounds 1, 2, 3 . . . etc.) refer to the structures so numbered in the process schematics. Additionally examples are provided which are illustrative of the distinctive biological characteristics of the new compounds, such characteristics serving as a basis for the application of these compounds in the treatment of metabolic bone disease.
Preparation of Compounds
General Procedures. Ultraviolet (UV) absorption spectra were recorded on a Shimadzu UV-Visible recording spectrophotometer. Proton nuclear magnetic resonance ( 1 H-NMR) spectra were recorded on a Bruker AM-500 multinuclear spectrometer at 500 MHz or on a JEOL JNM-GSX 270 FT NMR spectrometer at 270 MHz in chloroform-d (CDCl 3 ). Chemical shifts (δ) are reported downfield from internal tetramethylsilane (TMS: δ 0.00). Mass spectra (MS) were recorded at 70eV on a JEOL JMS-HX100 mass spectrometer equipped with a JEOL JMA-DA5000 mass data system. Silica gel 60 (Merck, 230-400 mesh) was used for column chromatography. High performance liquid chromatography (HPLC) was performed using a Waters Associates Liquid chromatography equipped with a Model 6000A solvent delivery system, a Model U6K injector and a Model 450 variable wavelength detector or using a Shimadzu L-6AD liquid chromatograph system equipped with a Rheodyne 7125 injector, a Shimadzu SPD-6A UV spectrophotometric detector, a Shimadzu FCV-100B fraction collector and a Shimadzu C-R4A chromatopac. Tetrahydrofuran was distilled from sodium-benzophenone ketyl under nitrogen. Other solvents were purified by standard method.
In the Process Scheme the following abbreviations are employed:
Et: ethyl
Ts: toluenesulfonyl
Ph: phenyl
Bn: benzyl
Bu: butyl
THF: tetrahydrofuran
Me: methyl
DMAP: 4-dimethylaminopyridine
DMF: N,N-dimethylformamide
mCPBA: 3-chloroperbenzoic acid
TES: triethylsilyl
Tf: trifluoromethanesulfonyl
It should be noted that in the present description and in the Scheme, compound 12 is a known compound and may be prepared in accordance with PCT Patent Application No. WO88/07545.
EXAMPLE 1
Synthesis of Four Isomers of 26,28-Methylene-1α, 25-dihydroxyvitamin D 2 (compounds 15a, 15a', 15b and 15b'; Process Scheme).
The synthesis of compounds 15a, 15a', 15b and 15b' may be summarized as follows:
The starting material was commercially available ethyl 2-oxocyclopentanecarboxylate 1. The ketone group was protected as an acetal (compound 2) and the ester was reduced with lithium aluminum hydride to yield alcohol 3. The hydroxyl group of 3 was protected as a benzyl ether (compound 4) and the ketone functionality was regenerated by treatment with an acid catalyst in acetone to provide ketone 5. On treatment with methylmagnesium bromide were obtained the diastereomeric alcohols 6a and 6b, which were able to be separated by chromatography, and thereafter the two diastereomers were converted separately.
The benzyl protective group of 6a was removed under hydrogenation condition to give diol 7a. The primary hydroxyl group of diol 7a was converted into the corresponding tosylate (compound 8a), and the tosyloxy group was substituted with phenylthio group on treatment with thiophenoxide to yield phenylsulfide 9a. The phenylsulfide was oxidized with a peracid to the corresponding phenylsulfone (compound 10a), and finally the protection of the hydroxyl group as a silyl ether to give the side chain sulfone 11a. In the same manner, the diastereomer 6b was converted into the sulfone 11b.
Julia olefination methodology was used for coupling with a steroidal aldehyde 12 and formation of the trans double bond. Thus, the anion of the sulfones 11a or 11b was condensed with aldehyde 12, and the resulting hydroxy sulfone was submitted to reductive elimination reaction with sodium amalgam, after treated with acetic anhydride, to give compound 13a or 13b, respectively. Deprotection of the silyl protective groups with fluoride ion provided the provitamins 14a and 14b, which were converted into mixtures of vitamin D derivatives 15a and 15a', or 15b and 15b', respectively, in a usual manner (photo- and thermoisomerization, followed by deprotection). HPLC purification and separation gave four possible isomers 15a, 15a', 15b and 15b', derived from the chiral centers of carbon-24 and carbon-25.
6-Ethoxycarbonyl-1,4-dioxaspiro [4.4]nonane 2.
A mixture of ethyl 2-oxocyclopentanecarboxylate (Aldrich, 10.0 g, 64.0 mmol), ethylene glycol (18 mL, 323 mmol), triethyl orthoformate (21 mL, 126 mmol) and p-toluenesulfonic acid monohydrate (0.61 g, 3.21 mmol) in toluene (150 mL) was heated under reflux with removing distillate with a Dean-Stark apparatus for 1 h. The mixture was cooled and poured into NaHCO 3 solution, and the organic layer was separated. The aqueous layer was extracted with diethyl ether, and the combined organic layers were washed with NaCl solution and dried over Na 2 SO 4 . Filtration and concentration gave 16.41 g of 2, as a pale yellow oil, which was used in the next reaction without further purification.
1 H-NMR δ (ppm, 500 MHz): 1.27 (3H, t, J=7.3 Hz), 1.58-1.73 (1H, m), 1.77-1.88 (2H, m), 1.88-1.98 (2H, m), 2.07-2.17 (1H, m), 2.90 (1H, t, J=8.0 Hz), 3.86-3.98 (3H), 3.98-4.06 (1H, m), 4.09-4.23 (2H,m).
6-Hydroxymethyl-1,4-dioxaspiro [4.4]nonane 3.
To a suspension of lithium aluminum hydride (2.43 g, 64.0 mmol) in diethyl ether (50 mL) was added a solution of 2 (16.41 g, crude) dropwise under nitrogen in an ice bath over a period of 50 min. To the mixture was added lithium aluminum hydride (1.2 g) and the mixture was stirred for 25 min. To the mixture were added water (3.6 mL), 15% NaOH solution (10.8 mL), water (10.8 mL) and Na 2 SO 4 (20 g). The mixture was filtered through a pad of Celite and washed thoroughly with EtOAc. The filtrate and washings were combined and concentrated to give 10.95 g of 3, as a pale yellow oil, which was used in the next reaction without further purification.
15 ( 1 H-NMR δ (ppm, 500 MHz): 1.49-1.96 (6H), 2.14 (1H, m), 2.65 (1H, br s), 3.57-3.75 (2H), 3.85-4.08 (4H).
6-Benzyloxymethyl-1,4-dioxaspiro [4.4]nonane 4.
To a suspension of sodium hydride (60% dispersion, 2.82 g, 70.5 mmol) in THF (30 mL) was added a solution of 3 (10.95 g, crude) in THF (50 mL) dropwise in an ice bath over a period of 30 min. To the mixture was added tetra-n-butylammonium iodide (2.36 g, 6.39 mmol), followed by benzyl chloride (9 mL, 78.2 mmol), and the mixture was stirred at ambient temperature overnight. The mixture was heated under reflux for 50 min. The mixture was cooled and poured into ice water, and the organic layer was separated. The aqueous layer was extracted with diethyl ether, and the combined organic layers were washed with NaCl solution, and dried over Na 2 SO 4 . Filtration and concentration gave 21.02 g of an oily material, which was purified by column chromatography (SiO 2 gel 100 g, EtOAc in n-hexane 0-10%), to give 12.94 g (81.4% from 1) of 4, as a pale yellow oil.
1 H-NMR δ (ppm, 500 MHz): 1.42-1.56 (1H, m), 1.56-1.87 (4H), 1.97 (1H, m), 2.29 (1H, m), 3.37 (1H, dd, J=9.4 and 7.6 Hz), 3.59 (1H, dd, J=9.4 and 6.2 Hz), 3.79-4.01 (4H), 4.50 (1H, d, J=12.0 Hz), 4.52 (1H, d, J=12.0 Hz), 7.24-7.43 (5H).
2-Benzyloxymethylcyclopentan-1-one 5.
A mixture of 4 (7.95 g, 32.0 mmol) and p-toluenesulfonic acid monohydrate (0.30 g, 1.58 mmol) in acetone (160 mL) was stirred at ambient temperature for 100 min. The mixture was neutralized with NaHCO 3 solution and acetone was evaporated under reduced pressure. The residue was diluted with water and extracted with EtOAc. The combined organic layers were washed with NaCl solution and dried over Na 2 SO 4 . Filtration and concentration gave 8.94 g of an oily material, which was purified by column chromatography (SiO 2 gel 50 g EtOAc in n-hexane 5-10%), to give 5.83 g (89.2%) of 5, as a pale yellow oil.
1 H-NMR δ (ppm, 500 MHz): 1.80 (1H, m), 1.93 (1H, m), 2.05 (1H, m), 2.14 (1H, m) 2.20-2.43 (3H), 3.63 (1H, dd, J=9.0 and 6.2 Hz), 3.67 (1H, dd, J=9.0 and 4.1 Hz), 4.49 (2H, s), 7.20-7.42 (5H).
(1R S, 2R S)-2-Benzyloxymethyl-1-methylcyclopentan-1-ol 6a and its (1S R, 2R S)-isomer 6b.
To a solution of 5 (5.83 g, 28.5 mmol) in diethyl ether (60 mL) methylmagnesium bromide (3.0M solution in diethyl ether; 10.5 mL, 31.5 mmol) was added dropwise over a period of 5 min under nitrogen in an ice bath. The mixture was stirred for 10 min and the reaction was quenched by an addition of NH 4 Cl solution. The organic layer was separated and the aqueous layer was extracted with diethyl ether. The combined organic layers were washed with NaCl solution, and dried over Na 2 SO 4 . Filtration and concentration gave 6.57 g of an oily material. Repeated chromatographic separation on SiO 2 gel gave 3.11 g (49.5%) of 6a, as a pale yellow oil, and 2.18 g (34.7%) of 6b, as a colorless oil.
1 H-NMR δ (ppm, 500 MHz): 6a 1.34 (3H, s), 1.49-1.94 (7H), 2.78 (1H, br s), 3.65 (2H), 4.51 (1H, d, J=11.9 Hz), 4.56 (1H, d, J=11.9 Hz), 7.25-7.42 (5H); 6b 1.19 (3H, s), 1.48-1.88 (6H), 2.22 (1H, m), 2.57 (1H, br s), 3.45 (1H, t, J=8.8 Hz), 3.53 (1H, dd, J=8.8 and 4.6 Hz), 4.51 (2H, s), 7.26-7.45 (5H).
(1R S, 2R S)-2-Hydroxymethyl-1-methylcyclopentan-1-ol 17a.
A solution of 6a (3.11 g. 14.1 mmol) in ethanol (60 mL) was hydrogenated over palladium-charcoal (10%, 0.3 g) at ambient temperature for 1.5 h. The mixture was filtered through a pad of Celite. The filtrate was concentrated to give 1.78 g of 7a, which was used in the next reaction without further purification.
(1S R, 2R S)-2-Hydroxymethyl-1-methylcyclopentan-1-ol 7b.
In the same manner as for 7a, 6b (2.18 g, 9.90 mmol) was converted into 1.05 g of 7b, which was used in the next reaction without further purification.
(1R S, 2R S)-1-Methyl-2-p-toluenesulfonyloxymethylcyclopentan-1-ol 8a.
To a mixture of 7a (1.78 g, crude), pyridine (5.5 mL, 68.0 mmol) and 4-dimethylaminopyridine (0.17 g, 1.37 mmol) in CH 2 Cl 2 (40 mL) was added p-toluenesulfonyl chloride (3.13 g, 16.4 mmol) in one portion, and the mixture was left to stand at 4° C. overnight. The mixture was stirred at ambient temperature for 100 min. To the mixture was added ice and the mixture was stirred at ambient temperature and the organic layer was separated. The aqueous layer was extracted with EtOAc and the combined organic layers were washed with water, CuSO 4 solution, water, NaHCO 3 solution and NaCl solution, and dried over Na 2 SO 4 . Filtration and concentration gave 3.86 g of 8a, which was used in the next reaction without further purification.
(1S R, 2R S)-1-Methyl-2-p-toluenesulfonyloxymethylcyclopentan-1-ol 8b.
In the same manner as for 8a, 7b (1.05 g, crude) was converted into 2.12 g of 8b, which was used in the next reaction without further purification.
(1R S, 2S R)-1-Methyl-2-phenylthiomethylcyclopentan-1-ol 9a.
To a solution of 8a (3.86 g, crude) and triethylamine (9.6 mL, 68.9 mmol) in N,N-dimethylformamide (30mL) was added thiophenol (2.1 mL, 20.5 mL) in one portion, and the mixture was stirred at ambient temperature overnight. To the mixture was added thiophenol (1.1 mL) and the mixture was stirred for 40 min. To the mixture was added NaI (catalytic amount) and the mixture was stirred for 85 min. To the mixture was added triethylamine (5 mL) and the mixture was stirred for 145 min. To the mixture was added thiophenol (2 mL) and tetra-n-butylammonium iodide (catalytic amount) and the mixture was stirred for 35 min. The mixture was poured into cold diluted HCl, and extracted with diethyl ether. The combined organic layers were washed with cold diluted HCl, water, NaHCO 3 solution and NaCl solution, and dried over Na 2 SO 4 . Filtration and concentration gave 6.40 g of an oily material, which was purified by column chromatography (SiO 2 gel 100 g, EtOAc in n-hexane 1-20%), to give 1.84 g (60.4% from 6a) of 9a, as a pale yellow oil.
1 H-NMR δ (ppm, 500 MHz): 1.35 (3H, s), 1.49-1.67 (3H), 1.67-1.80 (2H), 1.82 (1H, m), 2.02 (1H, m), 2.89 (1H, dd, J=12.2 and 9.0 Hz), 3.21 (1H, dd, J=12.2 and 9.0 Hz), 7.16 (1H, t, J=7.3 Hz), 7.28 (2H, dd, J=7.8 and 7.3 Hz), 7.33 (2H, d, J=7.8 Hz).
(1S R, 2S R)-1-Methyl-2-phenylthiomethylcyclopentan-1-ol 9b.
In the same manner as for 9a, 8b (2.12 g, crude) was converted into 1.48 g (82.5% from 6b) of 9b, as a pale yellow oil.
1 H-NMR δ (ppm, 500 MHz): 1.24 (3H, s), 1.36 (1H, m), 1.58 (1H, m), 1.62-1.81 (3H), 1.93 (1H, br s), 1.96-2.12 (2H), 2.81 (1H, dd, J=12.5 and 4.9 Hz), 3.07 (1H, dd, J=12.5 and 6.5 Hz), 7.19 (1H, t, J=7.2 Hz), 7.29 (2H, dd, J=7.6 and 7.2 Hz), 7.35 (2H, d, J=7.6 Hz).
(1R S, 2S R)-2-Benzenesulfonylmethyl-1-methylcyclopentan-1-ol 10a.
To a mixture of 9a (1.84 g, 8.28 mmol) and NaHCO 3 (2.45 g, 29.2 mmol) in a mixture of CH 2 Cl 2 (40mL) and water (17 mL) was added mCPBA (85%, 3.36 g, 16.5 mmol) in portionwise with stirring vigorously in an ice bath. The mixture 19 was stirred for 15 min. To the mixture were added water (16 mL), NaHCO 3 (2.45 g) and mCPBA (1.68 g), and stirring was continued for 20 min. The excess amount of peracid was decomposed with Na 2 S 2 O 3 solution in the presence of a catalytic amount of KI. The organic layer was separated, and the aqueous layer was extracted with EtOAc. The combined organic layers were washed with NaCl solution, and dried over Na 2 SO 4 . Filtration and concentration gave 2.69 g of 10a, as white solids, which was used in the next reaction without further purification.
(1S R, 2S R)-2-Benzenesulfonylmethyl-1-methylcyclopentan-1-ol 10b.
In the same manner as for 10a, 9b (1.48 g, 6.66 mmol) was converted into 2.14 g of 10b, as a pale yellow viscous oil, which was used in the next reaction without further purification.
(1R S, 2S R)-2-Benzenesulfonylmethyl-1-methyl-1-triethylsiloxy-cyclopentane 11a.
To a solution of 10a (2.69 g, crude) and imidazole (5.6 g, 82.3 mmol) in CH 2 Cl 2 (50 mL) was added chlorotriethylsilane (1.7 mL, 10.1 mmol), and the mixture was stirred at ambient temperature overnight. To the mixture were added 2,6-lutidine (1.9 mL, 16.3 mmol) and triethylsilyl trifluoromethanesulfonate (1.9 mL, 8.40 mmol), and the mixture was stirred at ambient temperature for 35 min, then heated under reflux. Heating and stirring were continued with further addition of triethylsilyl trifluoromethanesulfonate (0.8 mL) overnight. Ice was added to the mixture, and the organic layer was separated. The aqueous layer was extracted with n-hexane, and the combined organic layers were washed with cold diluted HCl, water, NaHCO 3 solution and NaCl solution, and dried over Na 2 SO 4 . Filtration and concentration, followed by chromatographic purification (SiO 2 gel 50 g, EtOAc in n-hexane 5%), to give 3.21 g (quantitative yield from 9a) of 11a, as a colorless oil.
1 H-NMR δ (ppm, 500 MHz): 0.54 (6H, q, J=7.9 Hz), 0.90 (9H, t, J=7.9 Hz), 1.21 (3H, s), 1.44-1.63 (3H), 1.63-1.78 (2H), 1.81-1.96 (2H), 3.07 (1H, dd, J=14.7 and 9.9 Hz), 3.31 (1H, d, J=14.7 Hz), 7.56 (2H, dd, J=7.5 and 7.4 Hz), 7.64 (1H, t, J=7.4 Hz), 7.92 (2H, d, J=7.5 Hz).
(1S R, 2S R)-2-Benzenesulfonylmethy-1-methyl-1-triethylsiloxy-cyclopentane 11b.
In the same manner as for 11a, 10b (2.14 g, crude) was converted into 3.21 g (quantitative yield from 9b) of 12b, as a colorless oil.
1 H-NMR δ (ppm, 500 MHz): 0.46 (6H, q, J=7.8 Hz), 0.84 (9H, t, J=7.8 Hz), 0.99 (3H, s), 1.27 (1H, m), 1.45-1.75 (4H), 1.96-2.15 (2H), 2.89 (1H, dd, J=13.1 and 12.0 Hz), 3.37 (1H, d, J=13.1 Hz), 7.56 (2H, dd, J=8.0 and 7.4 Hz), 7.64 (1H, t, J=7.4 Hz), 7.91 (2H, d, J=8.0 Hz).
(22E, 24R, 25R)-and (22E, 24S, 25S)-3β-tert-Butyldiphenylsiloxy-1α-methoxycarbonyloxy-26,28-methylene-25-triethylsiloxy-ergosta-5,7,22-triene 13a.
To a solution of 11a (574 mg, 1.56 mmol) in THF (10 mL) was added a solution of LiNEt 2 (prepared from 0.54 mL of diethylamine and 3.1 mL of 1.6N n-butyllithium in n-hexane in 6.8 mL of THF; 3.4 mL) dropwise under nitrogen in a dry ice-MeOH bath over a period of 30 min. A solution of (20S)-3β-tert-butyldiphenylsiloxy-1α-methoxycarbonyloxy-20-methylpregna-5,7-dien-21-al 12 (1.00 g, 1.56 mmol) in THF (10 mL) was added to the mixture dropwise at the same temperature over a period of 25 min. The reaction was quenched by an addition of NH 4 Cl solution and the mixture was allowed to warm to ambient temperature. The organic layer was separated, and the aqueous layer was extracted with EtOAc. The combined organic layers were washed with NaCl solution, and dried over Na 2 SO 4 . Filtration and concentration gave 1.84 g of a crude product, which was used in the next reaction without further purification.
A mixture of the crude product (1.84 g), 5 4-dimethylaminopyridine (1.91 g) and acetic anhydride (0.74 mL) in CH 2 Cl 2 (40 mL) was stirred at ambient temperature under nitrogen overnight. To the mixture was added ice, and the mixture was stirred at ambient temperature. The organic layer was separated, and the aqueous layer was extracted with EtOAc. The combined organic layers were washed with NaCl solution, and dried over Na 2 SO 4 . Filtration and concentration gave 2.45 g of a crude product, as a pale yellow oil, which was used in the next reaction without further purification.
To a solution of the crude product (2.45 g) in a mixture of THF (20 mL) and MeOH (20mL) was added Na 2 HPO 4 (6.6 g, 46.5 mmol), and the mixture was stirred at -40°--50° C. under nitrogen. To the mixture was added Na--Hg (5%, 7.17 g, 15.6 mmol), and the mixture was stirred at the same temperature for 1.5 h. To the mixture was added Na 2 HPO 4 (13.2 g) and Na--Hg (14.4 g), and the mixture was stirred at the same temperature for 1 h and then at -30°--40° C. for 1.25 h. The mixture was filtered through a pad of Celite and washed with EtOAc. The filtrate and washings were poured into NaCl solution, and the organic layer was separated. The aqueous layer was extracted with EtOAc, and the combined organic layers were washed with NaCl solution, and dried over Na 2 SO 4 . Filtration and concentration gave 3.21 g of a crude product, which was purified by column chromatography (SiO 2 gel 50 g, EtOAc in n-hexane 1-3%) to give 719 mg (54.1%) of 13a, as white foams.
1 H-NMR δ (ppm, 500 MHz): 0.55 (6H, q, J=7.9 Hz), 0.60 (3H, s), 0.93 (9H, t, J=7.9 Hz), 0.98 (3H, s), 0.96-1.04 (3H), 1.05 (9H, s), 1.20 (3H, s), 2.47 (2H, d, J=7.9Hz), 3.64 (3H, s), 3.97 (1H, m), 4.63 (1H, br s), 5.11-5.26 (1H), 5.26-5.43 (2H), 5.53 (1H, d, J=5.6 Hz), 7.32-7.45 (6H), 7.64 (4H, d, J=8.1 Hz).
(22E, 24R, 25S)- and (22E, 24S, 25R)-3β-tert-Butyldiphenyl-siloxy-25-triethylsiloxy-1α-methoxycarbonyloxy-26,28-methyleneergosta-5,7,22-triene 13b.
In the same manner as for 13a, 11b (574 mg, 1.56 mmol) was converted into 569 mg (42.8%) of 13b, as white foams.
1 H-NMR δ (ppm, 500 MHz): 0.55 (6H, q, J=7.9 Hz), 0.59 (3H, s), 0.93 (9H, t, J=7.9 Hz), 0.98 (3H, s), 0.96-1.03 (3H), 1.05 (9H, s), 1.08, 1.09 (3H, two s), 2.47 (2H, d, J=7.9 Hz), 3.64 (3H, s), 3.96 (1H, m), 4.63 (1H, br s), 5.10-5.28 (2H), 5.31 (1H, br s), 5.53 (1H, d, J=5.4 Hz), 7.31-7.47 (6H), 7.64 (4H, d, J=7.1 Hz).
(22E, 24R, 25R)-and (22E, 24S, 25S)-1α-Methoxycarbonyloxy-26,28-methyleneergosta-5,7,22-triene-3.beta.,25-diol 14a.
To a solution 13a (719 mg, 0.845 mmol) in THF (15 mL) was added a solution of tetra-n-butylammonium fluoride (1.0M in THF, 2.5 mL), and the mixture was stirred at ambient temperature for 1.5 h. A solution of tetra-n-butylammonium fluoride (1.0M in THF, 2.5 mL) was added twice to the mixture, and the mixture was stirred at ambient temperature overnight. The mixture was poured into cold NaHCO 3 solution, and the mixture was extracted with EtOAc. The combined organic layers were washed with NaCl solution, and dried over Na 2 SO 4 . Filtration and concentration gave 0.97 g of a crude product, which was purified by column chromatography (SiO 2 gel 30 g, EtOAc in n-hexane 20-50%), to give 373 mg (88.5%) of 14a, as white solids.
1 H-NMR δ (ppm, 500 MHz): 0.64 (3H, s), 1.01 (3H, s), 1.05, 1.06 (3H, two d, J=5.8 and 6.1 Hz), 1.25 (3H, s), 3.78 (3H, s), 4.01 (1H, m), 4.82 (1H, br s), 5.28-5.48 (3H), 5.66 (1H).
(22E, 24R, 25S)- and (22E, 24S, 25R)-1α-Methoxycarbonyloxy-26,28-methyleneergosta-5,7,22-triene-3.beta.,25-diol 14b.
In the same manner as for 14a, 13b (569 mg 0.668 mmol) was converted into 300 mg (90.2%) of 14b, as white solids.
1 H-NMR δ (ppm, 500 MHz): 0.63 (3H, s), 1.01 (3H, s), 1.04, 1.05 (3H, two d, J=7.1 Hz), 1.13 (3H, s), 3.78 (3H, s), 3.99 (1H, m), 4.82 (1H, br s), 5.25-5.35 (2H), 5.36 (1H), 5.66 (1H).
(22E, 24R, 25R)- and (22E, 24S, 25S)-26,28-Methylene-9,10-secoergosta-5,7,10 (19), 22-tetraene-1α,3β,25-triol 15a and 15a'.
A solution of 14a (100 mg, 0.201 mmol) in a mixture of diethyl ether (100 mL) and benzene (20 mL) was irradiated with a medium pressure mercury lamp through a Vycor filter for 30 min in an ice bath with nitrogen bubbling through the reaction mixture. The mixture was concentrated under reduced pressure, and the residue was dissolved in benzene (20 mL) and the solution was left to stand under nitrogen at ambient temperature for 16 days. The mixture was concentrated under reduced pressure and the residue was treated with 1N LiOH solution (1 mL) in MeOH (9 mL) in an ice bath under nitrogen for 6.3 h. The mixture was poured into ice water, and extracted with EtOAc. The combined organic layers were washed with NaCl solution and dried over Na 2 SO 4 . Filtration and concentration, followed by chromatographic purification (SiO 2 gel 5 g, EtOAc in n-hexane 50-80%), gave 22.9 mg of a diastereomeric mixture of 15a and 15a'. Preparative HPLC [Zorbax Pro- 10 SIL (Mitsui-Toatsu), 20 mmφ×250 mm, 80% EtOAc in n-hexane] gave 7.1 mg (8.0%) of 15a, which was eluted faster, and 12.9 mg (14.6%) of 15a', which was eluted slower.
15a: UV (EtOH): λmax 262 nm,λmin 228 nm.
1 H-NMR δ (ppm, 270 MHz): 0.56 (3H, s), 1.05 (3H, d, J=6.7 Hz), 1.24 (3H, s), 4.23 (1H, m), 4.43 (1H, m), 5.00 (1H, br s), 5.32 (1H, br s), 5.28-5.50 (2H), 6.01 (1H, d, J=11.0 Hz), 6.38 (1H, d, J=11.0 Hz).
MS m/z: 440 (M + ), 422 (base peak), 404, 386, 269, 251, 155, 135, 105, 93, 81.
15a': UV (EtOH): λ max 261 nm, λ min 227 nm.
1 H-NMR δ (ppm, 270 MHz): 0.56 (3H, s), 1.04 (3H, d, J=6.7 Hz), 1.24 (3H, s), 4.23 (1H, m), 4.43 (1H, m), 5.00 (1H, br s), 5.23-5.48 (2H), 5.35 (1H, br s), 6.01 (1H, d, J=11.0 Hz), 6.38 (1H, d, J=11.0 Hz).
MS m/z: 440 (M + ), 422 (base peak), 404, 386, 269, 251, 155, 135, 105, 93, 81.
(22E, 24R, 25S)- and (22E, 24S, 25R)-26,28-Methylene-9,10-secoergosta-5,7,10 (19), 22-tetraene-1α,3β,25-triol 15b and 15b.
A solution of 14b (100 mg, 0.201 mmol) in a mixture of diethyl ether (100 mL) and benzene (20 mL) was irradiated with a medium pressure mercury lamp through a Vycor filter for 30 min in an ice bath with nitrogen bubbling through the reaction mixture. The mixture was concentrated under reduced pressure, and the residue was dissolved in benzene (20 mL) and the solution was left to stand under nitrogen at ambient temperature for 16 days. The mixture was concentrated under reduced pressure and the residue was treated with 1N LiOH solution (1 mL) in MeOH (9 mL) in an ice bath under nitrogen for 6.3 h. The mixture was poured into ice water, and extracted with EtOAc. The combined organic layers were washed with NaCl solution and dried over Na 2 SO 4 . Filtration and concentration, followed by chromatographic purification (SiO 2 gel 5 g, EtOAc in n-hexane 50-80%), gave 21.3 mg of a diastereomeric mixture of 15b and 15b'. Preparative HPLC [Zorbax Pro- 10 SIL (Mitsui-Toatsu), 50 mmφ×250 mm, 80% EtOAc in n-hexane] gave 6.3 mg (7.1%) of 15b, which was eluted faster, and 4.5 mg (5.1%) of 15b', which was eluted slower.
15b: UV (EtOH): λ max 263 nm, λ min 228 nm.
1 H-NMR δ (ppm, 270 MHz): 0.56 (3H, s), 1.03 (3H, d, J=6.7 Hz), 1.13 (3H, s), 4.23 (1H, m), 4.43 (1H, m), 5.00 (1H, br s), 5.14-5.43 (2H), 5.32 (1H, br s), 6.01 (1H, d, J=11.0 Hz), 6.38 (1H, d, J=11.0 Hz).
MS m/z: 440 (M + ), 422 (base peak, 404, 386, 269, 251, 155, 135, 105, 93, 81.
15b': UV (EtOH): λmax 264 nm,λmin 227 nm.
1 H-NMR δ (ppm, 270 MHz): 0.56 (3H, s), 1.03 (3H, d, J=6.7 Hz), 1.13 (3H, s), 4.23 (1H, m), 4.43 (1H, m), 5.00 (1H, br s), 5.10-5.42 (2H), 5.32 (1H, br s), 6.01 (1H, d, J=11.0 Hz), 6.38 (1H, d, J=11.0 Hz).
MS m/z: 440 (M + ), 422 (base peak), 404, 386, 269, 251, 155, 135, 105, 93, 81.
Biological Activity
EXAMPLE 2
Calcemic Activity
Weanling male rats obtained from the Holtzman Company were fed a low calcium (0.02%), 0.3% phosphorus, vitamin D-deficient diet for three weeks. After this time, the animals were severely hypocalcemic. They were then implanted with Alzet minipumps that delivered approximately 13 μL of solution per day which contained the indicated dose in Tables 1 and 2 dissolved in 5% ethanol, 95% propylene glycol. After 7 days the rats were killed and the duodena were used for determination of intestinal calcium transport by the everted intestinal sac technique (Martin & DeLuca, 1967) and serum calcium (bone calcium mobilization). The tests were made against the 1α,25-dihydroxyvitamin D 3 standard and are reported in Tables 1 and 2.
TABLE 1______________________________________INTESTINAL CALCIUM TRANSPORT AND BONECALCIUM MOBILIZING ACTIVITIES OF 26,28-METHYLENE-1α,25-DIHYDROXYVITAMIND.sub.2 COMPOUNDS SERUM AMOUNT CALCIUM μgs/ S/M (mean ± S.E.M.)GROUP d/7 days (mean ± S.E.M.) (mg/100 ml)______________________________________D Deficient 0 3.72 ± 0.31 3.81 ± 0.09LT I (15 b) 0.1 9.08 ± 0.40 6.12 ± 0.65 0.5 9.85 ± 0.78 8.50 ± 0.33LT II (15 b') 0.1 8.42 ± 0.50 4.8 ± 0.22 0.5 8.82 ± 0.70 5.8 ± 0.091,25(OH).sub.2 D.sub.3 0.1 9.1 ± 0.23 5.91 ± 0.12______________________________________ Stereoisomers of 26,28 Methylene 1α,25(OH).sub.2 D.sub.3 : ##STR3## ##STR4## LTisomers 15 b and 15 b'-
The results show that the LT-II 26,28 methylene-1,25-dihydroxyvitamin D 2 compounds are less active than 1,25-dihydroxyvitamin D 3 in the mobilization of calcium from bone. The amount of bone calcium mobilizing activity is considerably less than 1,25-dihydroxyvitamin D 3 . However, both of the 26,28-methylene-D 2 compounds have highly significant intestinal calcium transport activity. The LT compounds, therefore, by showing preferential activity on intestinal calcium transport and reduced calcium mobilizing activity in bone suggest that they would be preferred agents for the treatment of a disease where bone loss is a major issue, such as osteoporosis, osteomalacia and renal osteodystrophy. The LT-1 and UC compounds are effective on bone calcium mobilization and, therefore, would be useful where low bone turnover osteoporosis is found, i.e. age-related osteoporosis.
TABLE 2______________________________________ SERUM AMOUNT CALCIUM μgs/ S/M (mean ± S.E.M.)GROUP d/7 days (mean ± S.E.M.) (mg/100 ml)______________________________________D Deficient 0 4.9 ± 0.16 4.6 ± 0.15UC I (15 a) 0.1 8.6 ± 0.73 7.01 ± 0.21 0.5 6.2 ± 1.03 9.39 ± 0.18UC II (15 a') 0.1 4.7 ± 0.39 6.15 ± 0.13 0.5 8.9 ± 1.07 9.48 ± 0.121,25(OH).sub.2 D.sub.3 0.1 9.0 ± 0.73 7.38 ± 0.61______________________________________ Stereoisomers of 26,28 Methylene 1α,25(OH).sub.2 D.sub.3 : ##STR5## ##STR6## UC-isomers 15 a and 15 a'-
For treatment purposes, the novel compounds of this invention may be formulated for pharmaceutical applications as a solution in innocuous solvents, or as an emulsion, suspension or dispersion in suitable solvents or carriers, or as pills, tablets or capsules, together with solid carriers, according to conventional methods known in the art. Any such formulations may also contain other pharmaceutically-acceptable and non-toxic excipients such as stabilizers, anti-oxidants, binders, coloring agents or emulsifying or taste-modifying agents.
The compounds may be administered orally, parenterally or transdermally. The compounds are advantageously administered by injection or by intravenous infusion of suitable sterile solutions, or in the form of liquid or solid doses via the alimentary canal, or in the form of creams, ointments, patches, or similar vehicles suitable for transdermal applications. Doses of from 0.5 μg to 50 μg per day of the compounds are appropriate for treatment purposes, such doses being adjusted according to the disease to be treated, its severity and the response of the subject as is well understood in the art. Since the new compounds exhibit specificity of action, each may be suitably administered alone, in situations where only calcium transport stimulation is desired, or together with graded doses of another active vitamin D compound--e.g. 1α-hydroxyvitamin D 2 or D 3 , or 1α,25-dihydroxyvitamin D 3 --in situations where some degree of bone mineral mobilization (together with calcium transport stimulation) is found to be advantageous. ##STR7##
Various modes of carrying out the invention are contemplated as being within the scope of the following claims particularly pointing out and distinctly claiming the subject matter regarded as the invention. | Vitamin D 2 analogs in which a cyclopentane ring is introduced into the side chain of 1α,25-dihydroxyvitamin D 2 . The compounds are characterized by a marked intestinal calcium transport activity while exhibiting much lower activity than 1α,25-dihydroxyvitamin D 3 in their ability to mobilize calcium from bone. Because of their preferential calcemic activity, these compounds would be useful for the treatment of diseases where bone formation is desired, such as osteoporosis. | 2 |
CROSS REFERENCE TO RELATED APPLICATIONS
This application claims priority of German patent application no. 10 2005 042 214.4 filed Sep. 5, 2005, which is incorporated by reference herein.
FIELD OF THE INVENTION
The invention relates to a receiving and transferring station for coverslipped specimen slides.
BACKGROUND OF THE INVENTION
In clinical laboratories or pharmaceutical companies and at research service provider facilities, a large number of different samples are processed every day and prepared for histological investigations by scientists, physicians, and pathologists. The usual procedure is to take the sample from the patient, embed the sample in, for example, paraffin, and then cut it into thin sections using microtomes.
The thin sections are, as a rule, placed onto specimen slides and covered with a thin glass or plastic plate for protection from environmental influences. To enhance diagnosis capabilities, the samples are often stained with different staining techniques before coverslipping.
In order to meet ever more stringent requirements in clinical and pathological histology and cytology, and to maintain competitiveness despite enormous time and cost pressure, many activities previously performed manually by laboratory personnel are being streamlined with the aid of automatic equipment.
For example, so-called stainers (automatic staining machines) have become known for staining the samples. Coverslipping of the specimen slides is facilitated by coverslipping machines.
It is known from DE 101 44 042 A1 and DE 101 44 989 A1 to connect a stainer, via a transfer module, to a coverslipping machine and to transport stained sections automatically for coverslipping. In this fashion, a large number of coverslipped samples are produced at short time intervals and are made available, at the output end of the system, for further investigation.
Subsequent investigation of the samples by physicians, scientists, and pathologists requires substantially more time, however, and also occurs more irregularly than the production of coverslipped samples on specimen slides using the system described above. Even automatically operating digital scanning devices, which convert the samples into high-resolution “digital slides,” take between two and 20 minutes to scan a specimen slide, depending on the size of the specimen. It is common to have a backup of finished coverslipped specimen slides at the output end of the coverslipping machine.
SUMMARY OF THE INVENTION
The object of the invention is to simplify and maximally automate handling, over the entire evaluation process, of specimen slides for histology. The intention is to automate the transfer of stained and coverslipped specimen slides to a downstream digital specimen slide scanner system, and to absorb any possible backup resulting from different processing times prior to scanning.
This object is achieved, according to the present invention, by a receiving and transferring station for coverslipped specimen slides that contains at least one vertically upright magazine frame, open toward the receiving side, for at least one specimen slide magazine having horizontally oriented compartments, and a rotation apparatus, connected to the magazine frame and having a vertically upright rotation axis, for conveying the magazine frame from a receiving position into a transferring position.
For vertical shifting and easy filling of the compartments in the specimen slide magazines, the magazine frame comprises a transport device for vertical displacement of the specimen slide magazines. In this fashion, the individual compartments of the specimen slide magazines can be brought progressively into the receiving position. In an alternative embodiment, a transport apparatus for vertical displacement is located in the lower housing region of the receiving and transferring station, and introduces the specimen slide magazines from below into the magazine frames.
The invention is distinguished by the fact that the height of the magazine frame is provided for the reception two specimen slide magazines, thereby increasing the receiving capacity.
For easy filling of the magazine frame with empty specimen slide magazines, the latter are insertable from above into the magazine frame. Filled specimen slide magazines are of course also removable from above in this fashion.
If the rotation apparatus contains a turntable on whose periphery multiple magazine frames are mounted, the receiving and transferring station can receive a plurality of specimen slides. If six magazine frames are arranged evenly on the periphery of the turntable, rotational control of the apparatus can be configured in particularly simple fashion.
In a further embodiment of the invention, there is arranged above the turntable, at a location intersected by the rotation axis, a stationary ejection apparatus whose ejection arms are shiftable in the direction of the transferring position in a compartment plane, in order to transfer individual specimen slides to the next processing apparatus. With a particular embodiment of the ejection apparatus, however, it is also possible to convey a magazine either vertically upward or downward out of the magazine frame, and thus transfer the magazine as a unit.
An electronically controllable rotation apparatus makes it possible, in the context of the receiving and transferring station according to the present invention, on the one hand to position magazine frames having empty specimen slide magazines in the receiving region in specific fashion. On the other hand, the possibility exists of delivering magazine frames having filled specimen slide magazines to the transfer position, and ejecting the specimen slides there.
For that purpose, the ejection apparatus is advantageously likewise embodied in electronically controllable fashion.
With an electronically controllable embodiment of the transport device for vertical displacement, the procedure of sliding specimen slides into the compartments of the specimen slide magazines can be synchronized and optimized interactively with the ejection apparatus and the rotation apparatus.
In particularly advantageous fashion, the receiving position of the receiving and transferring station for coverslipped specimen slides is associated with the output side of a coverslipping machine. Cyclical introduction of the specimen slides produced in the coverslipping machine into compartments of the specimen slide magazines takes place with no further intervening manual step.
For easy filling of the specimen slide magazines, the magazines are lowerable within the magazine frame in the receiving position. This makes it easy to adapt to existing coverslipping machines, which comprise at their output side only a horizontal shifting (dispensing) of the coverslipped specimen slides. Further possibilities for introducing specimen slides into the receiving and transferring station according to the present invention are, of course, not intended to be excluded from protection. For example, with an appropriate configuration of the substructure of the apparatus in the receiving position, it is also possible to push empty specimen slide magazines under the magazine frames and insert them from below into the magazine frames. With this filling method, as soon as the lowest compartment of a specimen slide magazine is filled with a coverslipped specimen slide, the specimen slide magazines can be secured in the magazine frame to prevent them from slipping out, and the rotation apparatus can deliver the next empty magazine frame to the receiving position.
In a further embodiment of the invention, the transferring position of the receiving and transferring station is associated with a digital scanning device for producing so-called digital slides. This makes possible, especially in coaction with the electronically controllable ejection apparatus, a controlled automatic transfer of specimen slides. If the scanning operation requires more time because of the size of the sample, it is possible to link the control system of the receiving and transferring station to that of the scanning device, and allow the latter to generate the instruction to transfer the next specimen slide to be scanned. Operation in terms of receiving specimen slides can otherwise continue without interference during a scanning procedure, until the supply of empty compartments in the receiving and transferring station has been exhausted. The transfer of specimen slides to the scanning device can proceed autarchically with no supervision by operating personnel, including at night. A backup that has occurred as a result of the rapid (as compared with the scanning operation) reception of coverslipped specimen slides can be cleared in this fashion.
The invention is further distinguished by the fact that the receiving position and the transferring position can be arranged with a 180-degree offset from one another. This makes possible an ergonomic and space-saving configuration of a system made up of a coverslipping machine, receiving and transferring station, and digital scanning device arranged next to one another.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will be described and explained in more detail below with reference to an exemplifying embodiment depicted schematically in the drawings, in which:
FIG. 1 shows a receiving and transferring station viewed obliquely from above; and
FIG. 2 shows a receiving and transferring station in an arrangement between a coverslipping machine and a digital scanning device.
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 shows a receiving and transferring station 1 for coverslipped specimen slides 2 , 2 ′, 2 ″, in which station a specimen slide magazine 4 , located in a receiving position 3 , is depicted in a lowered position. Specimen slide magazine 4 is inserted in vertically shiftable fashion in a magazine frame 5 . Coverslipped specimen slides 2 are located in the horizontally oriented compartments 6 . Specimen slide magazine 4 is vertically shifted, by a transport device (not depicted further) for vertical displacement of compartments 6 , until an open compartment 6 can be filled with a coverslipped specimen slide 2 ′. Projecting out in the lower region of magazine frame 5 is a second, empty specimen slide magazine 4 ′ that, for the reception of further specimen slides 2 ′, is inserted upward into magazine frame 5 via the transport device for vertical adjustment. As soon as specimen slide magazine 4 ′ is also filled with specimen slides 2 , 2 ′, specimen slide magazines 4 , 4 ′ are secured by way of a locking mechanism (not depicted further) to prevent magazine frames 5 , 5 ′, 5 ″ from slipping or falling out.
Magazine frames 5 , 5 ′, 5 ″ comprise, in the rear region, vertically extending guide grooves 15 . In the base region of specimen slide magazines 4 , 4 ′, shaped-on lateral ridges 16 engage into guide grooves 15 . Specimen slide magazines 4 , 4 ′ are thereby guided vertically in magazine frames 5 , 5 ′, 5 ″. For easy manual insertion of specimen slide magazines 4 , 4 ′ into magazine frames 5 , 5 ′, 5 ″, guide grooves 15 comprise a widened groove cross section 17 in the upper region.
A rotation apparatus performs a rotary motion, thereby causing magazine frame 5 to be moved toward transferring position 8 . On the periphery of the rotation apparatus, which is embodied as a turntable 7 , multiple magazine frames 5 , 5 ′, 5 ″ having recesses 9 are arranged in the base region of magazine frames 5 , 5 ′. As a result of the rotary motion, magazine frame 5 ″ having specimen slides 2 ″ is delivered to transferring position 8 . At transferring position 8 specimen slides 2 ″ are transferred, by an ejection apparatus 10 having ejection arms 11 , to a digital scanning device 12 depicted schematically in FIG. 1 .
FIG. 2 is an overall view of a system made up of a coverslipping machine 13 , receiving and transferring station 1 that is described more thoroughly in FIG. 1 , and a digital scanning device 12 . All the controllable apparatuses can be monitored and programmed via a control panel 14 of an electronic control device.
Codes, with which an allocation of the sample to a patient record and sample record in a database system can be performed, are advantageously applied onto the specimen slides 2 , 2 ′, 2 ″. A code applied onto the specimen slide magazine 4 , 4 ′ makes possible, together with a stored compartment number, a determination of the exact introduction position of a specimen slide even after a specimen slide magazine has been removed from the receiving and transferring station. Specific recovery of individual samples from a plurality of samples is facilitated. This makes possible, in coaction with the electronic control systems of the receiving and transferring station, a variety of automatic working sequences. For example, the samples can be transferred to the downstream digital scanning device 12 in almost any desired sequence. Prioritized samples can be handled preferentially with no need to wait for the processing of previously introduced specimen slides. The possibility also exists of delivering further specimen slides to the specimen slide magazines in the receiving region during the scanning operation. The reception of further specimen slides can be briefly interrupted in order to return a sample that has just been scanned, without creating a backup in the coverslipping machine 13 . It is likewise possible first to scan all the samples that have a short scanning time, in order to gain rapid access to a plurality of scanning results. The processing of specimen slides having samples with a longer scanning time can be postponed in order to process them later, for example at night without supervision. In the case of a sequential processing of the samples in the order in which they were introduced into the specimen slide magazines (FIFO principle), the possibility exists of transferring scanned specimen slides to a storage system downstream from the digital scanning device. As a result, empty specimen slide magazines are constantly leaving the transferring position, and empty specimen slide magazines are constantly being delivered to the receiving region. If there is no storage system placed downstream from the scanning device, and if the specimen slides must therefore be introduced back into the specimen slide magazine at the same position after scanning of the sample is complete, filled specimen slide magazines can be removed from the receiving and transferring station after leaving the transferring position. On the basis of the code on the specimen slide and on the specimen slide magazines, and information from the database system, specific access to individual samples is possible at any later time.
PARTS LIST
1 Receiving and transferring station for coverslipped specimen slides
2 , 2 ′, 2 ″ Specimen slides
3 Receiving position
4 , 4 ′ Specimen slide magazine
5 , 5 ′, 5 ″ Magazine frames
6 Compartment
7 Turntable
8 Transferring position
9 Recesses
10 Ejection apparatus
11 Ejection arms
12 Digital scanning device
13 Coverslipping machine
14 Control panel
15 Guide groove
16 Ridges
17 Widened groove cross section | A receiving and transferring station ( 1 ) for coverslipped specimen slides ( 2, 2′, 2 ″) comprises at least one vertically upright magazine frame ( 5 ), open toward the receiving side, for at least one specimen slide magazine ( 4 ) having horizontally oriented compartments ( 6 ), and a rotation apparatus, connected to the magazine frame ( 5 ) and having a vertically upright rotation axis, for conveying the magazine frame ( 5 ) from a receiving position ( 3 ) into a transferring position ( 8 ). | 8 |
FIELD OF THE INVENTION
[0001] The present invention relates to a method and system for increasing the efficiency of a response to a transmitted instant message and in particular to an instant messaging method and system that determines the current capacity of a primary instant message recipient and automatically redirects a transmitted instant message to an alternate recipient when the a primary instant message recipient has reached its current message capacity.
BACKGROUND OF THE INVENTION
[0002] Electronic mail (email) communications are an integral part of any business, and widely used outside of business as well. Although several new technologies currently compete with it, as the most ubiquitous tool in business communications, email remains one of the single most used communications tools for both the business and the personal user. Widespread availability, ease of use, and functionality are key components which hold email in front of developing communications methods; however, as new technologies compete for the top spot, email applications must continue to build upon the strong foundation currently in place to maintain their edge as the tool of choice. By any current standard, email applications would have to be rated as mature technology; however, if improvements in email applications cease to move forward, and other tools continue to improve, loss of market share will undoubtedly result.
[0003] E-mail has been the standard form of communication and information exchange. Telephone via the personal computer and shared collaboration are widely accepted and utilization of these modes are growing daily. Although E-mail is the main form of Internet communication, other new and popular forms of Internet communication, such as chat rooms and instant messaging (“IM”) have emerged.
[0004] Online chatting is a way of communicating by sending text messages in real-time to people in the same chat-room. The oldest form of true chat rooms are the text-based variety. The most popular of this kind is Intent Relay Chat (IRC). However, there are also talkers and havens. The popularity of these kinds of chat rooms have waned over the years, but IRC's popularity still remains strong. Also a notable number of people were introduced to chat rooms from AOL and web chat sites. The primary use of a chat room is to share information via text with a group of other users. New technology has enabled the use of file sharing and webcams to be included in some programs.
[0005] Instant messaging sessions (‘M’) are an emerging type of real time communication service. IM is somewhat like email, however, it should not be confused with a chat room. An instant messaging session is an “instant place” where two or more people can send text messages to each other. Both parties are online at the same time, and they “talk” to each other by typing these text messages and sending small pictures in instantaneous time. IM is based on instant messaging client programs that two separate people install, and those programs connect to send real-time typed messages to each other via an instant messaging service. This IM software allows a person to “talk” online with his/her friends in other rooms, other cities, and even other countries. The software uses the same cables and networks as any web page or email connection. As long as the other person has compatible IM software, IM works very well.
[0006] An instant messaging session starts when a person sends a text message to another person. This initial IM session is between two people. Other people can also join the instant messaging session. The current implementation of instant messaging sessions requires one of the session participants to invite the additional person to the session. The instant messaging session ends when the last user leaves the chat session.
[0007] Instant messaging is also becoming prevalent as a private extension to chat groups and is in use by over ten million people today. Instant messaging (IM) is an Internet protocol (IP)—based application that provides convenient communication between people using a variety of different device types. The most familiar today is computer-to-computer instant text messaging, but IM also can work with mobile devices, such as digital cellular phones, and can incorporate voice or video.
[0008] The millions of people using current Internet IM services and the growing popularity of short text messaging on mobile phones demonstrate that a market exists for IM services. Carriers can take advantage of this opportunity by offering advanced messaging services that integrate both fixed and mobile access and add new features that are not possible on free Web-based messaging services.
[0009] Because IM is a text-based service, instant messaging communication is generally not burdened by the need to transfer large graphic, sound, or program files. As a result, instant messaging is a relatively quick and easy to use system. In addition, instant messaging is widely available and its value as a means to access and retrieve data from a remotely located automated system is steadily increasing. One example of the expansion of instant messaging is a system, which interactively responds to and services requests from remotely located users. Such requests can include queries for general or specific information, requests to access and control various “WEB-enabled” devices, requests to store information for later use, reminder and paging services, as well as additional request-based functionality, such as suitable for use in various e-commerce environments.
[0010] Instant messaging allows end users to select “buddies” and assign these buddies to “buddy groups,” automatically register a person when on-line, advertise the user's selected buddies to the user when the selected buddies register on-line, advertise the user's presence on-line to others who have selected the user as a buddy, and participate in instant messaging communication between two on-line users. As mentioned, instant messaging has become a very popular form of communication. In addition, IM has become a basic tool that people use to conduct business. Many users create “buddy lists” using this instant messaging technology. These buddy names serve as point-to-point contacts for transmitting messages instead of entering a specific email address. Referring to FIG. 1 , shown in a diagram of a typical communication network system over which an instant messaging buddy system can be implemented in accordance with the present invention. The network system includes a plurality of user stations 102 having a network link 104 . The network link 104 is for receiving and transmitting data in analog or digital form over a communications network, such as the Internet. The communications network 100 connects each user station 102 as a “client” to a logon system 106 , which is typically a software program executing on an instant messaging server on a network. Instant message servers can handle various aspects of the instant message transmissions. A primary function of the instant messaging server is to provide an awareness list of the potential message recipients to the sender clients. For instance if John is a messaging client and he has a list of 10 people in his buddy list, the buddy list will show John which of those 10 people is available and which are not, depending on the information stored in the messaging server. In addition, during the initial negotiation of the messaging session from a messaging client (sender) to a message recipient, the instant messaging server gives the sender client the contact details of how to contact the message recipient. Many Internet service related companies, i.e. Yahoo, AOL and Microsoft offer instant messaging services and have instant messaging servers to facilitate the services for their clients.
[0011] The logon system 106 communicates with a “Buddy List System” 108 , which is preferably a software program executing on the IM server. The Buddy List System 108 maintains a database 110 for storing user information. The database 108 may be of any type, such as relational or hierarchical, and may be centralized or distributed. For example, the database 110 may be stored at least in part on each user's own station 102 . In such a case, the database 110 contents would be transmitted to the Buddy List System 108 when the user logged into the system.
[0012] Instant messaging provides an extremely useful tool to increase productivity. In fact many corporations rely heavily on IM as part of their business process. In the customer service context, one-way client users contact merchant businesses via instant messaging. However, while instant messaging can be a valuable tool, IM can become overwhelming to the user when too many client requests come in at once to a single user. Currently, to delegate an incoming instant message to others, that is have another user handle the instant message, one can invite others to the chat session, type some message to perform the handoff (message transfer) and either leave the chat session or watch the window to insure that the request is being handled correctly. All of these processes are currently manual. Since hundreds of instant messaging delegations can occur per week, and they often occur for similar problems, some efficiency can be achieved by automating these delegations based on message content.
[0013] Other efforts have developed methods to improve instant messaging efficiency. Joyce et al. U.S. Publication No.: 20050111653 describes a method and apparatus is provided to process an instant message call within a customer interaction system. The method includes receiving the instant message call at the customer interaction system and processing the instant message call within the customer interaction system with other interaction types based on information associated with the instant message call. In general, embodiments described below feature a customer interaction system that receives and processes an instant message call with other interaction types based on information associated with the instant message call. In one embodiment, the instant message call is processed at a customer interaction system comprised of media specific customer interaction systems and a multimedia customer interaction system. The media specific customer interaction system associated with instant message calls receives and immediately forwards the instant message call to the multimedia customer interaction system for allocation to a live blended agent. In another embodiment, the instant message call is processed at the media specific customer interaction system without forwarding to the multimedia customer interaction system for allocation to a live agent. For example, the media specific customer interaction system associated with instant message calls would respond to an incoming instant message call by allocating an automated agent.
[0014] Neumann et al. in U.S. Pat. No. 6,744,761 describe a method and system for handling, that is routing and tracking, a plurality of incoming media streams of varying types—such as faxes, e-mail, Voice over IP.
[0015] Miloslavsky in U.S. Pat. No. 6,732,156 describes a system for routing electronic mails to one of a plurality of support persons in a processing center is disclosed. Each person has a skill set that is suitable for responding to a certain type of e-mail message. The system comprises an e-mail server for receiving the e-mail message from a sender, an information extractor for extracting relevant information from the e-mail, and a router for routing the e-mail. The router can make routing decisions and perform load-balancing and alert functions based on the information stored in the database and the server.
[0016] Although Miloslavsky does describe a method for routing e-mail messages, IM technology currently does not have the capability to forward an instant message sent that is sent to a recipient that is currently at their capacity with regard to the number of instant messages they can receive. Currently technology does not automatically forward newly received instant messages, but only sends a reply to the message sender stating that the recipient cannot receive messages at the present time. There remains a need for a method and system by which a primary recipient of an instance message can automatically designate an alternate location to receive and reply to an instant message when the primary IM recipient has reached their capacity to receive additional instant messages. The alternate location delegation can be based on a specific rule or a set or combination rules unique to that particular primary instant message recipient.
SUMMARY OF THE INVENTION
[0017] The present invention provides a method and system to receive and delegate instant messages. A primary instant message resource location (a location that initially receives an incoming instant message) can define alternate instant message destinations to which the primary instant message resource device can automatically delegate a received instant message. The delegated location of the incoming instant message can be based on whether an incoming message contains certain content.
[0018] The method of this invention can initially generate a set of rules that will govern the delegating of instant messages from a primary instant message resource device to alternate instant message resource devices. These rules are stored in a primary instant messaging resource device. During operations, when an instant is received from a client at an instant messaging resource, there is a determination of whether the instant messaging resource is available to receive the incoming message. If the instant message resource is not available, then this method hands off or transfers the incoming instant message to an alternate instant message resource by inviting an alternate instant message resource to connect to the instant message where the client is currently connected. At this point, the instant message request from the client can be addressed by the alternate instant messaging resource.
[0019] The system of the present invention includes a communication network that connects an instant message request from a sender with a primary instant message recipient. The primary instant message recipient device contains a storage location with rules that govern the routing of certain instant message requests that are received at the primary instant message recipient. The instant message connection occurs in an instant messaging session between the sender and the primary message recipient. This system of the present invention also contains one or more alternate instant message recipients that receive certain instant messages from the primary instant message recipient when the primary instant message recipient simultaneously receives multiple instant messages.
[0020] A primary element of the present invention is that a potential delegation list for instant messages is stored and managed by each actual individual messaging recipient location. The recipient of the instant messaging request is really the one that best knows the expertise of the potential alternate recipients as compared to some centrally managed instant messaging administrator. Therefore, it is more efficient to track this knowledge distribution for each instant message recipient in each instant messaging recipients delegation list. The detailed description delegation (knowledgebase) for each instant message recipient is stored in a distributed knowledgebase, rather than a centrally server-stored knowledgebase.
DESCRIPTION OF THE DRAWINGS
[0021] FIG. 1 is an illustration of a typical network for implementation of an instant messaging system.
[0022] FIG. 2 is an illustration of a network and instant messaging system for implementation of the present invention.
[0023] FIG. 3 is a flow diagram of the steps in the implementation of the method of the present invention.
[0024] FIG. 4 is an illustration of a configuration of a rules repository within an instant messaging resource in accordance with the present invention.
[0025] FIG. 5 is an illustration of a rules repository record in accordance with the present invention.
[0026] FIG. 6 is a detailed flow diagram of the steps in the implementation of the method of the present invention.
DESCRIPTION OF THE INVENTION
[0027] The description of an implementation of the present invention will be in context of a customer service application. In such an application, client users (customers) contact the merchant representatives seeking assistance with user problems or issues. These contacts occur through instant message transmissions via computing devices at both the client user and merchant representative points. The computer device at the merchant representative contains the software that implements the method of the present invention.
[0028] The present invention detects when a situation exists where the number of requests being received at an instant message device for a merchant representative exceeds a predetermined threshold number of requests that the device can service at one time. In this invention, once there has been a determination that the number of instant message requests exceeds the threshold (more requests than ability to handle at an instant message resource) there is a transfer or routing of instant message requests to alternate instant message representatives. In the present invention, a rules engine is included in the instant messaging device/resource of the merchant representative to provide guidelines for where to forward instant messages in excess of the threshold number for that representative. Software also contained in the merchant representative's instant messaging resource can identify the content of an incoming message and apply filters (rules) to route the message when appropriate to a specific alternate instant message resource.
[0029] FIG. 2 is a configuration of an instant messaging system that can be used in the implementation of the present invention. This system comprises multiple computing devices that are capable of sending and receiving instant messages. A client user 200 has the capability to interact with the system of the invention by sending and receiving instant messages via a computing device 202 that has instant messaging capabilities. This computing device 202 could be a PDA commonly used in IM applications. In the implementation of the present invention, the instant messenge requestor device 202 communicates with other instant messenger devices via a communication network such as the Internet 204 . The present invention can create instant messaging session 206 through an instant message server. This server 206 functions to establish the instant message session between a sender device 202 and a receiver device 208 . Entities that provide instant messaging services have servers that facilitate this instant messaging service. The merchant representatives also interact with the method and system of the present invention through computing devices 208 , 212 and 216 . As mentioned, the initial communication within the present invention is between the instant messenger device 202 and the instant messenger resource 208 . This IM resource device 208 has similar functionality to the PDA device of 202 . However resource 208 contains additional storage capabilities for instant messaging designation rules and instant message designation software. In addition, the configuration of the present invention contains alternate instant messenger resource devices, 212 and 216 which are used by alternate merchant representatives. These alternate merchant representatives 214 and 218 serve as backup support in the event that the instant message device 208 for the merchant representative 210 receives multiple instant messages in excess of a predefined number simultaneously or at approximately the same time.
[0030] FIG. 3 shows the general steps in the implementation of the method of the present invention. In this method, a client user 200 employs instant messaging via device 202 to make a request of the merchant representative 210 via instant messenger resource device 208 . In the business world, this request could be for some form of technical support. In step 300 , the system of the present invention receives an instant message request. This instant message is received at IM device 208 . Receipt of this message creates an instant message session between devices 202 and 208 . This particular instant messaging session is directly between the user client user 200 making a request and the merchant representative 210 . In the event the instant messenger resource device 208 receives multiple requests simultaneously or in close proximity to one another, step 302 will determine whether the current number of requests at device 208 exceeds a predetermined threshold number for that device. This determination could be through maintaining a current count of the number of instant message being serviced by that representative. For example, the number of current IM messages can be five messages. The threshold number can also be five messages. When a sixth message is detected, the determination would be that the number of received messages has exceeded the threshold number. In this case, step 304 will automatically invite an alternate resource into the instant message session to address the concern or issue of the user requester of the latest (6 th ) received instant message. Once the alternate resource has been invited into the instant message session, step 306 generates a message to handoff (transfer) the instant message request from the user to the alternate resource. After the handoff has occurred, step 308 verifies that the transfer is complete. The alternate representative will then address the issue of the contained in the sixth message.
[0031] FIG. 4 illustrates an instant messaging resource (computing device) 208 used in the implementation of the present invention. As mentioned, stored in this device is a set of rules that govern the transferring of an instant message request to an alternate instant message resource. A rules repository 402 contains the rules that govern the transferring or forwarding of instant messages from the primary instant message resource 208 to alternate instant message resources 212 and 216 . This rules repository could reside inside the instant message resource 208 or it could reside in a remote storage device that the instant message device can access. Another location for this repository could be the instant messaging server. This device also contains software that performs the message designation functions. The software module 404 , which implements the method of the present invention described in FIGS. 3 and 6 , can also reside in the computing device 208 .
[0032] FIG. 5 is an illustration of a rules repository record in accordance with the present invention. As shown, each record can have multiple fields 500 , 502 and 504 . Each field can contain different types of information. One such field could be a rule identifier field 502 . This field would contain information about the rule that can be used to determine which rules and filters apply to an instant message. The information in identifier field 502 can also be used to arrange the rules in the repository. The rules could be searched according to the content in this identifier field. The rules record can also have a field that contains the actual coded rule. Once a rule is identified from the content of field 502 , the content of the rule could be read from a rule content field.
[0033] Each instant message could contain information describing the content of the message. The information could be included in a specific message field or header or in the main information content of the message. Key words or phrases can generally describe a problem encoutnered by a user or the general topic area of the message. Some examples of phrases can be ‘network failure’ or ‘slow system’. Since not everyone uses the same terminology to describe a situation, for some terms, incorporated in the software module 404 can be a process for associating a word with another word that has a similar meaning. A technique similar to the use of a thesaurus in word processing could implement this function. For example, if the user had a system that had stopped, the user may use the term ‘stopped’ in their instant message. The present invention would take the term ‘stopped’ and use it to identify a rule that may be related to a system stopping. However, the present invention can also use other words that have a similar meaning to ‘stopped’ such as ‘terminate’, ‘shutdown’, ‘close’ or ‘halt’ in the search for rules. Even though the sender used the term ‘stopped’ in the instant message, the rule search could produce a rule described as system termination that could be applicable to the request of the sender.
[0034] The method of the present invention can also generate and keep a history of message transactions and the proper routing location for these types of messages. The records could contain information about the source of an instant message, the destination of the message and the content of the message. These records can be generated and kept in the first IM representative device 208 as well as a second IM representative device 214 . This historical information could be used to track the routing of certain types of messages and to generate new message transfer rules. If the historical data shows a certain pattern for responding to certain types of messages, then a rule could be created to cover that particular response.
[0035] FIG. 6 is a detailed flow diagram of the steps in the implementation of the method of the present invention. The initial step 600 in this method is to generate a set of rules that will govern the forwarding of instant messages. For example, if a merchant representative knew that they were always going to forward requests for WebSphere help to a known WebSphere expert, a filter rule can be defined like;
[0000] if content like % WebSphere and monitorChatWindow=true if currentChats>2 delegate to WebSphereExpert.
[0036] As mentioned, these rules could reside in the rules repository 402 for the merchant representative receiving the instant messaging request. After the completion of the generation of the rules repository, the method goes into a monitor mode waiting to receive an instant messaging request. The second step 602 is to receive that instant message request at the device 208 for the merchant representative. In a customer service environment, the instant message resource may be for a service or help contact. The instant messages for the merchant representative are received at the IM device 208 . When the instant message is received at the merchant representative device, depending on the current activity of the instant message device, step 604 determines whether the device is available to receive another message. This determination could be based on the current number of instant messages that are being served through the IM device 208 . If the determination is that the instant message device is available to receive other messages then the method moves to box 606 and that representative handles the request. If in step 604 , the determination is that the number of messages at the IM device is currently at the determined threshold, then the method moves to step 608 , which analyzes the received instant message. Even though the IM device has reached capacity, the incoming message is still received at the IM device. However, it will not be served at the device. In conventional systems, when a resource is at capacity, the message is not taken and the sender receives a busy or unavailable message.
[0037] This step of analyzing the instant message involves identifying information in the message and when appropriate, applying a generated rule based on the information in the message. This information in the message could include the identity of the source of the message and the message content. Based on information in the message, there would be an identification of the appropriate rule for that type of message request. The rule could contain the destination of alternate representatives. Step 610 can determine whether a particular rule applies to the incoming message and whether an identified rule designates a specific resource for a certain type of instant message.
[0038] In many cases, the rule could be to delegate the message to next available IM resource. This approach could be a default process when no rule applies to message content. However, the rules could also stipulate that messages with certain content would automatically transfer to certain representatives regardless of the load status of the device initially receiving the message. This approach would necessitate examining content of each reached message. If certain content were found, rules governing that specific content would apply to that message.
[0039] For example, there may be an alternate instant message resource called WebSphere Expert. In addition, an instant message is received with the content “Help my WebSphere box won't start”. At the same time, the instant message device would be at its threshold number and therefore would be too busy with existing instant messages to handle a new message. The method of the present invention would automatically identify the WebSphere Expert as the designated resource device in step 610 . As mentioned, this identification would be based on one of the generated rules. If in step 610 , the rules did not provide a designated alternate resource device, then there could be a designated default device to forward messages. The designation of the default resource device could be a rule in the repository. Another rule could be to designate a certain resource device based on the identity of the message sender.
[0040] When there has been a determination of the alternate resource device in step 610 , step 612 would invite the alternate resource device into the instant messaging session. Step 614 would invite the default resource device into the instant messaging session. This default resource could be any alternate resource that is not at its' threshold number. In the present example, because WebSphere is identified in the message, step 612 would immediately invite the WebSphere Expert alternate resource into the instant messaging session. Step 616 would establish a handoff or transfer between the sender of the received instant message request and the alternate instant message resource device. Step 618 could inform the instant message requester of the handoff by entering a message saying, “Because the representative user is busy the instant message request has been delegated to WebSphere Expert” representative. In one preferred embodiment, the invention leaves the instant message window open so that a history is stored of how the request for help was handled. Step 620 would verify that the handoff of the message to the alternate resource device has occurred. In addition, notice that the automatic delegation above is activated depending on the currently active number of instant messaging sessions. For example, if 2 other instant messaging windows are currently occurring, this request will be delegated. If not, then the user will handle it directly.
[0041] The receipt of an incoming instant message at a resource device 208 , the determination that the device has reached its threshold capacity and the decision to transfer the incoming instant message to another resource device 212 can be performed in a manner that is transparent to the representative of the resource device 208 . The representative can receive a message informing them of the receipt and transfer of the message.
[0042] It is important to note that while the present invention has been described in the context of a fully functioning data processing system, those skilled in the art will appreciate that the processes of the present invention are capable of being distributed in the form of instructions in a computer readable medium and a variety of other forms, regardless of the particular type of medium used to carry out the distribution. Examples of computer readable media include media such as EPROM, ROM, tape, paper, poppy disc, hard disk drive, RAM, and CD-ROMs and transmission-type of media, such as digital and analog communications links. | An instant messaging system locates known delegates in its instant messaging list to which to automatically delegate messages based on whether an incoming message contains certain content. This method comprises the steps of simultaneously receiving multiple instant message requests at an instant message location. Initiating an instant message session with an alternate instant message resource device. After this initiation step, a handoff (transfer) message is generated to connect a received incoming instant message with the alternate instant message resource device. After the handoff, there is verification that the handoff has occurred. Those sending instant message questions could also get a quicker response to their question rather than waiting for one centralized person to manually delegate their question to a resource device. | 6 |
FIELD OF THE INVENTION
[0001] The present invention relates to the field of semiconductor manufacturing, and in particular to a failure detection method and a failure detection apparatus for metal interconnection lines in semiconductor devices.
BACKGROUND OF THE INVENTION
[0002] In the field of semiconductor manufacturing, failure analysis of semiconductor devices is a feedback procedure to improve reliability and stability of the manufacturing process, including finding and correcting the causes of defects to overcome problems resulting from the defects. Proper failure analysis is crucial in quality improvement of semiconductor devices. And improper failure analysis may prolong the cycle time it takes to develop and improve semiconductor device products. Failure analysis generally includes external examination, non-destructive analysis, electrical verification, destructive analysis, etc.
[0003] To improve the level of integration of a semiconductor device, it is desired to obtain as many elements as possible in a limited area, which further leads to increased complexity of the semiconductor device. Therefore, accurate analysis of the cause of a failure may not be possible by external examination or electrical performance detection alone, consequently, direct exposure of internal structure of the semiconductor device would be necessary for the study of failures.
[0004] As the linewidth shrinks to the 45-nanometer level, defects in metal interconnection lines may severely affect the performance of devices. Even a tiny defect may make a device completely useless. Therefore, failure analysis of internal metal interconnection lines is very important. Generally speaking, defects in metal interconnection lines include voids, particles, etc.
[0005] In the field of semiconductors, an existing method for failure analysis of chips is Optical Beam Induced Resistance Change (OBIRCH), which performs fault isolation using laser scanning techniques. Its general principle is illustrated in FIG. 1 . An external DC voltage is applied between an input terminal 2 and an output terminal 3 of a device under test 1 , and a laser beam scans an internal connection node 4 of the device, where functional regions or elements in the device are connected. Then the temperature varies due to the thermal effect of the laser, thereby causing a resistance change at the connection node 4 , which further leads to a current change at the output terminal 3 . The trend of the output current change is recorded, and compared with an output current change of a product without any defects under the same test, to locate the defect causing a failure. By using this method, the area where a defect is can be quickly located in a semiconductor device, and the defects can further be located precisely by repeating the test multiple times and narrowing down the range of the defect.
[0006] However, OBIRCH is only suitable for large-range defect locating for semiconductor devices, fails to meet the requirement for failure analysis in a small size, and suffers from poor electrical sensitivity for defect detection and low spatial resolution due to the spot size limited by the optical imaging system especially when the defect detection is performed on narrowly sized metal interconnection lines.
SUMMARY OF THE INVENTION
[0007] A technical problem solved by the invention is to provide a failure detection method and a failure detection apparatus, for locating defects in metal interconnection lines in semiconductor devices, and suitable for failure analysis in a small size.
[0008] To address the above issue, an embodiment of the invention provides a failure detection method for detecting a defect in an electrical conductor, including:
providing at least two output terminals on the electrical conductor under test, the at least two output terminals having identical electric potentials; inputting a constant detection current sequentially to detection points arranged on the electrical conductor under test along a predetermined path; detecting an output current at one or more output terminals of the at least two output terminals; building a correspondence relationship between the detected one or more output currents at the one or more output terminals and positions of the detection points, based on information of the positions of the detection points and information of the detected one or more output currents at the one or more output terminals; and determining from the correspondence relationship whether the detection points have a defect.
[0014] Further, an embodiment of the invention provides a failure detection method for detecting a defect in a wire, including:
providing an output terminal at both ends of the wire, the output terminals having identical electric potentials; inputting a constant detection current sequentially to detection points arranged on the wire along a predetermined path; detecting an output current at one or both of the output terminals; building a correspondence relationship between the detected one or both output currents at the one or both of the output terminals and positions of the detection points, based on information of the positions of the detection points and information of the detected one or both output currents at the one or both of the output terminals; and determining from the correspondence relationship whether the detection points have a defect.
[0020] Based on the failure detection method above, an embodiment of the invention provides a failure detection apparatus for detecting a defect in an electrical conductor under test, the electrical conductor being provided with at least two output terminals and the output terminals having identical electric potentials. The failure detection apparatus includes:
a detection current input module, adapted to input a detection current sequentially to detection points arranged on the electrical conductor under test along a predetermined path; an output current detection module, adapted to detect an output current at one or more output terminals of the at least two output terminals; and an analysis module, adapted to build a correspondence relationship between the detected one or more output currents at the one or more output terminals and positions of the detection points, based on information of the positions of the detection points and information of the detected one or more output currents at the one or more output terminals, to perform failure detection on the electrical conductor under test.
[0024] Compared with the prior art, the failure detection method provided by the invention uses detection points as input terminals for a direction current, and analyzes output currents at multiple output terminals, thereby achieving precise location of defects; and uses a charged particle beam as the detection current source to avoid the size limitation of irradiation points and the thermal effect, thereby satisfying the requirement for failure analysis in a small size and protecting the device under test from being damaged.
BRIEF DESCRIPTION OF THE DRAWINGS
[0025] The above and other objects, characteristics and advantages of the invention will become more apparent from the following detailed descriptions of preferred embodiments thereof as illustrated in the drawings. Components in the drawings the same as those in the prior art are denoted with identical reference numerals. The drawings are not necessarily drawn to scale but highlight the essence of the invention. For clarity, relevant structures are exaggerated in size in the drawings:
[0026] FIG. 1 is a diagram illustrating the principle of failure analysis using OBIRCH in the prior art;
[0027] FIG. 2 illustrates a flow chart of a failure detection method according to the invention;
[0028] FIG. 3 illustrates a flow chart of another failure detection method according to the invention;
[0029] FIG. 4 is a diagram illustrating the principle of a first embodiment of a failure detection method according to the invention;
[0030] FIG. 5 is a diagram illustrating an equivalent circuit of the first embodiment of the failure detection method according to the invention;
[0031] FIG. 6 illustrates a curve showing the relationship between currents at output terminals and positions of detection points according to the first embodiment of the invention;
[0032] FIG. 7 is a diagram illustrating the principle of a second embodiment of a failure detection method according to the invention;
[0033] FIG. 8 is a diagram illustrating an equivalent circuit of the second embodiment of the failure detection method according to the invention;
[0034] FIG. 9 illustrates a curve showing the relationship between currents at output terminals and positions of detection points according to the second embodiment of the invention; and
[0035] FIG. 10 illustrates a schematic diagram of a failure detection device according to an embodiment of the invention.
DETAILED DESCRIPTION OF THE INVENTION
[0036] According to the law of charge conservation, the total output current from a device is equal to the total input current. Therefore, if we place some output terminals having identical electric potentials on an electrical conductor (i.e., these output terminals are at the same electric potential), and input a detection current to the electrical conductor, the sum of currents at the output terminals is a fixed value. Because currents always flow along the path with the minimum resistance, the magnitudes of the currents at the output terminals depend on the resistances between the output terminals and the detection point. As the detection point changes its position, the magnitudes of the currents at the output terminals vary correspondingly in a fixed relationship, that is, if the same detection current is input at a fixed detection point, the output currents at the output terminals are fixed, and form a correspondence relationship with the position of the detection point. If a defect occurs at the detection point or adjacent to the detection point, under the same input detection current, the output currents at the output terminals vary, so does the correspondence relationship.
[0037] Based on the principle discussed above, according to characteristics of an electrical conductor under test, a failure detection method is provided below.
[0038] Reference is made to in FIG. 2 illustrating a flow chart of a failure detection method according to the invention, which includes the following steps.
[0039] S 20 . At least two output terminals are provided on an electrical conductor under test, and the output terminals have identical electric potentials; and a path along which detection points are arranged on the electrical conductor under test is predetermined.
[0040] Preferably, the output terminals are distributed on the electrical conductor under test as uniformly as possible.
[0041] S 21 . A constant detection current is input sequentially to the detection points arranged on the electrical conductor under test along the predetermined path.
[0042] Preferably, a beam of charged particles with a constant energy may be used as the detection current source to irradiate the detection points, and the beam of charged particles may be an electron beam or an ion beam.
[0043] S 22 . Output currents at the output terminals are detected; and a correspondence relationship between the output currents at the output terminals and positions of the detection points is built, based on information of the positions of the detection points and information of the output currents at the output terminals.
[0044] The correspondence relationship may be a curve of the magnitude, the rate of change or the like of an output current at one of the output terminals versus the positions of the detection points. Alternatively, the correspondence relationship may be a curve of a difference, a ratio, or the like between output currents at some of the output terminals versus the positions of the detection points. The correspondence relationship may also be determined according to actual needs such as whether it is easy to be expressed, whether the data collection can be done easily, etc.
[0045] S 23 . It is determined from the correspondence relationship whether the detection points have a defect.
[0046] Criteria for the determination are given below.
[0047] For an electrical conductor uniformly shaped and with a smooth transition, if no defect is present at a detection point or adjacent to the detection point, the correspondence relationship shall have a regular variation when the position of the detection point is moved along the predetermined movement path, and if the correspondence relationship varies irregularly at a detection point, we determine that a defect is present at the detection point or adjacent to the detection point.
[0048] For an electrical conductor having a sudden change in its shape or material, when the position of the detection point is moved along the predetermined movement path, the correspondence relationship shall also have a regular variation except at where the shape or material takes the known sudden change, and if the correspondence relationship varies irregularly at a detection point without the sudden change of shape or material, we determine that a defect is present at the detection point or adjacent to the detection point.
[0049] Moreover, the scenarios above may further be simplified if the electrical conductor under test is a wire. For a one-dimension wire, we may simply place grounded output terminals at both ends of the wire, and when the position of the detection point is moved along the wire while keeping the input detection current constant, the correspondence relationship of output currents at the two output terminals versus the position of the detection point shall have a substantially linear variation assuming that no defect is present in the wire, as derived in the following embodiment. If the correspondence relationship varies irregularly, we determine that a defect is present at the detection point or adjacent to the detection point.
[0050] Based on the above principle above, reference is made to in FIG. 3 illustrating a flow chart of another failure detection method according to the invention, which includes the following steps.
[0051] S 30 . Output terminals are provided at both ends of a wire, and the output terminals have identical electric potentials; and a path along which detection points are arranged on the wire is determined in advance. Preferably, both ends of the wire may be grounded directly, and the path along which the detection points are arranged may run from one end of the wire to the other end.
[0052] S 31 . A constant detection current is input sequentially to the detection points arranged on the wire along the predetermined path.
[0053] Preferably, a beam of charged particles with a constant energy may be used as the detection current source to irradiate the detection points, and the beam of charged particles may be an electron beam or an ion beam.
[0054] S 32 . Output currents at the output terminals are detected; and a correspondence relationship between the output currents at the output terminals and positions of the detection points is built based on information of the positions of the detection points and information of the output currents at the output terminals;
[0055] What the correspondence relationship is may be determined based on actual needs, which is omitted here, reference can be made to the failure detection method discussed above.
[0056] S 33 . It is determined from the correspondence relationship whether the detection points have a defect.
[0057] Criteria for the determination are given below:
[0058] If no defect is present at a detection point or adjacent to the detection point, the correspondence relationship shall have a linear variation when the position of the detection point is moved along the predetermined movement path, and if the correspondence relationship varies irregularly at a detection point, we determine that a defect is present at the detection point or adjacent to the detection point.
[0059] The two failure detection methods above are addressed for different failure detection requirements, and may be used individually or collectively according to actual situation of the device under test. For failure analysis in the field of semiconductors, e.g., the methods above can be used in combination due to the complexity of electrically conductive layers, interconnection lines, elements and the like in the semiconductor structure. For failure analysis for a specific semiconductor structure, we may first detect regional nodes, then interconnection lines, and finally elements, narrowing down the range of the defect step by step, thereby improving accuracy of failure detection and efficiency of failure analysis.
[0060] The failure detection methods above will be further described hereinafter in connection with the following embodiments.
[0061] Reference is made to FIG. 4 , a diagram illustrating a first embodiment of the failure detection method according to the invention.
[0062] Particularly, the electrical conductor under test is a metal plate uniform in material but irregular in shape. For simplicity, we assume the metal plate has a total length of L, consisting two parts with different thicknesses, one having a length of L 1 and a cross-sectional area of S 1 and the other one having a length of L 2 (L 2 =L−L 1 ) and a cross-sectional area of S 2 ; and we assume the metal plate has a resistivity of ρ. Two ends of the metal plate are grounded via a current meter A 1 and a current meter A 2 , respectively.
[0063] In failure detection, the metal plate is irradiated with a beam of charged particles with a constant energy, and is scanned along a predetermined movement path, while recording the change of output currents at the two output terminals and corresponding irradiation positions of the beam of charged particles. The beam of charged particles is equivalent to a constant current source having a current of I; the output currents recorded by the current meters A 1 and A 2 at the two output terminals are I 1 and I 2 , respectively; distance from the irradiation point, i.e., the detection point, to an end of the metal interconnection line connected with the current meter A 1 is x; and the metal interconnection line is divided by the detection point into a left part having a length of x and a resistance of R 1 , and a right part having a length of L−x and a resistance of R 2 .
[0064] Suppose the metal plate has a relatively large aspect ratio, which makes it possible to compare it to a one-dimension conductor, therefore we have:
[0065] The metal plate has a resistance per unit length of:
[0000]
ρ
l
=
ρ
/
S
;
R
1
=
{
∫
0
x
ρ
l
(
x
)
x
=
∫
0
x
ρ
(
x
)
/
S
1
x
(
x
≤
L
1
)
∫
0
x
ρ
l
(
x
)
x
=
ρ
L
1
/
S
1
+
∫
L
1
x
ρ
(
x
-
L
1
)
/
S
2
x
(
L
>
x
>
L
1
)
;
R
2
=
{
∫
0
x
ρ
l
(
x
)
x
=
∫
x
L
1
ρ
(
x
)
/
S
1
x
+
ρ
(
L
-
L
1
)
/
S
2
(
x
≤
L
1
)
∫
0
x
ρ
l
(
x
)
x
=
∫
x
1
L
ρ
(
L
-
x
)
/
S
2
x
(
L
>
x
>
L
1
)
;
R
1
+
R
2
=
ρ
L
1
/
S
1
+
ρ
(
L
-
L
1
)
/
S
2
=
R
;
[0000] where R represents the total resistance of the metal plate.
[0066] Reference is made to FIG. 5 illustrating an equivalent circuit of the above embodiment, that is, it is equivalent to connect the two parts of the metal plate in parallel and use the detection point as an input terminal to input the current I, and we have:
[0000]
I
1
=
R
2
R
I
I
2
=
R
1
R
I
;
[0067] Assuming that the end of the metal plate connected with the current meter A 1 is the origin, the positional coordinate of the detection point is x; and combining the equations above, we derive the following equations about the output currents I 1 and I 2 versus the positional coordinate x of the detection point:
[0000]
I
1
x
=
I
R
R
2
x
=
{
-
I
R
ρ
(
x
)
/
S
1
;
(
x
≤
L
1
)
-
I
R
ρ
(
x
)
/
S
2
;
(
L
>
x
>
L
1
)
I
2
x
=
I
R
R
1
x
=
{
I
R
ρ
(
x
)
/
S
1
;
(
x
≤
L
1
)
I
R
ρ
(
x
)
/
S
2
;
(
L
>
x
>
L
1
)
(
I
2
-
I
1
)
x
=
I
R
(
R
1
-
R
2
)
x
=
{
2
I
R
ρ
(
x
)
/
S
1
;
(
x
≤
L
1
)
2
I
R
ρ
(
x
)
/
S
1
;
(
L
>
x
>
L
1
)
;
[0068] Reflecting the equations above on the curves, we derive the correspondence relationship between the output currents at the two output terminals and the position of the detection point. The correspondence curves a and b are curves of the magnitudes of the currents at the two output terminals versus the coordinate of the detection point, respectively. The correspondence curve c is a curve of the rate of change of the difference between the currents at the two output terminals versus the coordinate of the detection point. According to the equations above, these curves are section curves, with the correspondence curves a and b have slopes of
[0000]
I
1
x
and
I
2
x
,
[0000] and the correspondence curve c has a curve function of
[0000]
(
I
2
-
I
1
)
x
.
[0069] Assuming defects are present at two coordinates x 1 and x 2 on the metal plate, which causes the resistivity there to be only ρ/2, i.e., half of that the resistivity of normal parts of the metal plate. Therefore, when the metal plate is scanned by the beam of charged particles from one end of the metal plate to the other end along a predetermined path along which the detection point is moved, the curves can be derived as illustrated in FIG. 6 .
[0070] As can be apparent from FIG. 6 , the correspondence curves a, b and c all vary irregularly at the three coordinates x 1 , L 1 and x 2 , and as can be derived from the above equations, the slopes of respective curves at x 1 and x 2 are twice as those in a normal case. We know that L 1 is where the sudden change in shape of the metal plate, therefore the corresponding irregular variation of the curves at L 1 shall be excluded. Hence, the specific location of a defect can be detected easily and intuitively with the failure detection method according to the embodiment of the invention.
[0071] It shall be noted that, in this embodiment the correspondence curves a, b and c represent the correspondence relationships of the output current I 1 , the output current I 2 , and the rate of change of the difference (I 2 −I 1 ) versus the position x of the detection point, respectively; however, in practice, any of the foregoing correspondence relationships may be used, and a corresponding output current may be detected, thereby accomplishing defect detection and finding. It is not necessary to detect at all the output terminals.
[0072] Reference is made to FIG. 7 illustrating a second embodiment of the failure detection method according to the invention.
[0073] Particularly, an electrical conductor under test is a metal interconnection line of a homogenous medium having a length of L, a cross-sectional area of S and a metal resistivity of ρ, in a semiconductor device. Two ends of the metal interconnection line are grounded via a current meter A 1 and a current meter A 2 , respectively.
[0074] In failure detection, the metal interconnection line is irradiated with a beam of charged particles with a constant energy, and is scanned along a predetermined movement path, while recording the change of output currents at the two output terminals and corresponding irradiation positions of the beam of charged particles. The beam of charged particles is equivalent to a constant current source having a current of I; the output currents recorded by the current meters A 1 and A 2 at the two output terminals are I 1 and I 2 , respectively; the distance between the irradiation point, i.e., the detection point, and an end of the metal interconnection line connected with the current meter A 1 is x; and the metal interconnection line is divided by the detection point into a left part having a length of x and a resistance of R 1 , and a right part having a length of L−x and a resistance of R 2 .
[0075] Therefore we have:
[0076] The metal interconnection line has a resistance per unit length of: ρ ι =ρ/S;
[0000] R 1 =∫ 0 x ρ ι ( x ) dx;
[0000] R 2 =∫ x L ρ ι ( x ) dx;
[0000] R 1 +R 2 =∫ 0 L ρ ι ( x ) dx =R;
[0000] where R represents the total resistance of the metal interconnection line.
[0077] Reference is made to FIG. 8 illustrating an equivalent circuit of the this embodiment, that is, it is equivalent to connect the two parts of the metal interconnection line in parallel and use the detection point as an input terminal to input the current I, and we have:
[0000]
I
1
=
R
2
R
I
I
2
=
R
1
R
I
;
[0078] Assuming that the end of the metal interconnection line connected with the current meter A 1 is the origin, the positional coordinate of the detection point is x; and combining the equations above, we derive the following equations about the output currents I 1 and I 2 versus the positional coordinate x of the detection point:
[0000]
I
1
x
=
I
R
R
2
x
=
-
I
R
ρ
l
(
x
)
I
2
x
=
I
R
R
1
x
=
-
I
R
ρ
l
(
x
)
(
I
2
-
I
1
)
x
=
I
R
(
R
1
-
R
2
)
x
=
2
I
R
ρ
l
(
x
)
;
[0079] Reflecting the three equations above on the curves, we derive the correspondence relationship between the output currents at the two output terminals and the position of the detection point. The correspondence curves a and b are curves of the magnitudes of the currents at the two output terminals versus the coordinate of the detection point, respectively. The correspondence curve c is a curve of the rate of change of the difference between the currents at the two output terminals versus the coordinate of the detection point. According to the equations above, the curves are straight lines, with the correspondence curves a and b have slopes of
[0000]
I
1
x
and
I
2
x
,
[0000] and the correspondence curve c has a curve function of
[0000]
(
I
2
-
I
1
)
x
.
[0080] Assuming defects are present at two coordinates x 1 and x 2 on the metal interconnection line, which cause the resistivity there to be only ρ/2, i.e., half of that the resistivity of normal parts of the metal interconnection line. Therefore, when the metal interconnection line is scanned by the beam of charged particles from one end to the other along a predetermined path along which the detection point is moved, the curves can be derived as illustrated in FIG. 9 .
[0081] As can be apparent from FIG. 9 , the correspondence curves a, b and c all vary irregularly at the two coordinates x 1 and x 2 , and as can be derived from the above equations, the slopes of respective curves at x 1 and x 2 are twice as those in a normal case. Therefore, the specific location of a defect can be detected easily and intuitively with the failure detection method according to the invention. Similar to the first embodiment, any of the foregoing correspondence relationships represented by the three correspondence curves above may be used, and a corresponding output current may be detected, thereby accomplishing defect detection and finding.
[0082] Based on the failure detection methods above, an embodiment of the invention provides a failure detection apparatus, for detecting a defect in an electrical conductor. The electrical conductor is provided with at least two output terminals, the output terminals have identical electric potentials, as illustrated in FIG. 10 . The failure detection apparatus mainly includes:
a detection current input module 10 , adapted to input a detection current sequentially to detection points arranged on an electrical conductor under test along with a predetermined path; a plurality of output current detection modules 20 , adapted to detect output currents at the output terminals; and an analysis module 30 , adapted to build a correspondence relationship between the output currents at the output terminals and positions of the detection points, based on information of the positions of the detection points and information of the output currents at the output terminals, to perform failure analysis on the electrical conductor under test.
[0086] The failure detection device further includes a movement means 12 and a bearing station 40 ; the movement means 12 is adapted to change a position where the electrical conductor under test is irradiated by a charged particle beam generator; and the bearing station 40 is adapted to bear and fix the electrical conductor under test.
[0087] Particularly, the detection current input module includes a charged particle beam emitter 11 which is adapted to generate a beam of charged particles to irradiate the electrical conductor under test.
[0088] The moving means 12 may directly align with and move the charged particle beam emitter 11 , and the bearing station 40 may be fixed such that the charged particle beam emitter 11 can scan the electrical conductor under test. Alternatively, the charged particle beam emitter 11 may be fixed, and the moving means 12 may drive the bearing station 40 bearing the electrical conductor under test such that the irradiation position of the beam of charged particles can be moved on the electrical conductor under test.
[0089] The output current detection modules 20 include a current meter, one end of the current meter is connected with the electrical conductor under test and the other end is connected with a fixed electric potential, e.g., the ground. Since the internal resistance of the current meter is considered to be zero, the output terminals of the electrical conductor are at the same electric potential.
[0090] The analysis module 30 may receive the information of the positions of the detection points generated by the movement means 12 and the information of the output currents at the output terminals generated by the output current detection module 20 , build the correspondence relationship between the output currents at the output terminals and the positions of the detection points, to perform failure analysis on the electrical conductor under test. Alternatively, the analysis module 30 may generate a scan path, control the movement means 12 in a way such that the electrical conductor under test is irradiated by the charged particle beam emitter 11 along the scan path, and detect the output currents at the output terminals by the output current detection module 20 , and build the correspondence relationship between the output currents at the output terminals and the positions of the detection points, to perform failure analysis on the electrical conductor under test.
[0091] Preferred embodiments of the invention are disclosed above, however, they are not intended to limit the scope of the appended claims. Those skilled in the art may make alternations and modifications without departing from the spirit and scope of the invention. Accordingly, the scope of the invention should be defined by the claims. | The present invention discloses a failure detection method and a failure detection apparatus for detecting a defect in an electrical conductor. The failure detection method includes: providing at least two output terminals on the electrical conductor under test, the at least two output terminals having identical electric potentials; inputting a constant detection current sequentially to detection points arranged on the electrical conductor under test along a predetermined path; detecting an output current at one or more output terminals of the at least two output terminals; building a correspondence relationship between the detected one or more output currents at the one or more output terminals and positions of the detection points, based on information of the positions of the detection points and information of the detected one or more output currents at the one or more output terminals; and determining from the correspondence relationship whether the detection points have a defect. The failure detection method according to the invention can precisely locate defects; and uses a charged particle beam as the detection current source to avoid the size limitation of irradiation points, thereby satisfying the requirement for failure analysis in a small size. | 6 |
FIELD OF THE INVENTION
The present invention relates to a recording material suited for use in direct thermal imaging. More in particular the present invention relates to a recording material based on a heat induced reaction between a substantially light insensitive organic silver salt and a reducing agent.
BACKGROUND OF THE INVENTION
In thermography two approaches are known:
1. Direct thermal formation of a visible image pattern by imagewise heating of a recording material containing matter that by chemical or physical process changes colour or optical density.
2. Thermal dye transfer printing wherein a visible image pattern is formed by transfer of a coloured species from an imagewise heated donor element onto a receptor element.
Thermal dye transfer printing is a recording method wherein a dye-donor element is used that is provided with a dye layer wherefrom dyed portions of incorporated dye is transferred onto a contacting receiver element by the application of heat in a pattern normally controlled by electronic information signals.
The optical density of transparencies produced by the thermal transfer procedure is rather low and in most of the commercial systems--in spite of the use of donor elements specially designed for printing transparencies--only reaches 1 to 1.2 (as measured by a Macbeth Quantalog Densitometer Type TD 102). However, for many application fields a considerably higher transmission density is asked for. For instance in the medical diagnostical field a maximal transmission density of at least 2.5 is desired.
High optical densities can be obtained using a recording material comprising on a support a heat sensitive layer comprising a substantially light insensitive organic silver salt and a reducing agent. Such material can be image-wise heated using a thermal head causing a reaction between the reducing agent and the substantially light insensitive organic silver salt leading to the formation of metallic silver. To obtain a good thermosensitivity heating is carried by contacting the thermal head with the heat sensitive layer. The density level may be controlled by varying the amount of heat applied to the recording material. This is generally accomplished by controlling the number of heat pulses generated by the thermal head. An image having a grey scale is thus obtained.
Because of its high density the image is in principal suitable for use as a medical diagnostic image. However the following problems have been encounterred. Uneveness of density occurs with the number of images that have been printed and damaging of the heat sensitive layer occurs. These problems can be overcome by making use of a protective layer. Although this brings a substantial improvement so that the image may be suitable for some applications, the images show scratches that are prohibitive for the use of the image in medical diagnostics.
SUMMARY OF THE INVENTION
It is an object of the present invention to improve the quality of images obtained by direct thermal imaging of a recording material comprising on a support (i) a heat sensitive layer comprising a substantially light insensitive organic silver salt and (ii) a reducing agent being present in the heat sensitive layer or another layer on the same side of the support carrying the heat sensitive layer.
Further objects of the present invention will become clear from the description hereinafter.
According to the present invention there is provided a recording material comprising on a support (i) a heat sensitive layer comprising a substantially light insensitive organic silver salt, (ii) a protective layer containing a matting agent dispersed in a binder and (iii) a reducing agent being present in the heat sensitive layer and/or another layer on the same side of the support carrying the heat sensitive layer.
According to the present invention there is provided a method for making an image comprising image-wise heating by means of a thermal head a recording material as defined above said thermal head contacting the protective layer of said recording material.
DETAILED DESCRIPTION
Thanks to the use of a matting agent in the protective layer the occurrences of scratches can be reduced and in some cases scratches are completely avoided. Suitable matting agents for use in connection with the present invention are particles that protrude from the protective layer and they can be organic or inorganic. They should be sufficiently large to avoid the scratches but are on the other hand limited in their size because of pinholes that may occur at places where a matting agent is present due to a reduced thermoconductivity at these places. Preferably the matting agent will have an average diameter between 0.7 and 1.5 times the thickness of the protective layer. It is also preferred that the matting agents for use in connection with the present invention are capable of withstanding the temperatures involved in the heating process according to the present invention. Generally they should be able to withstand a temperature of upto 400° C. without showing substantial deformations. The matting agent is preferably spherical in shape and is preferably used in an amount of 0.1 to 50% by weight more preferably in an amount of 0.25 to 30% by weight of the binder.
Examples of matting agents that can be used are silicone resin particles, silicates, alumina, polymethylmethacrylate particles, polyacrylate particles etc. . .
Preferred silicate particles having a mildly abrasive character are i.a. clay, China clay, talc (magnesium silicate), mica, silica, calcium silicate, aluminium silicate, and aluminium magnesium silicate. These particles are incorporated in the protective layer in such a way, i.e. by selecting the appropriate size with respect to the thickness of the protective layer and amount as described above, that at least part of them protrudes.
Examples of talc particles that can be used advantageously in accordance with the present invention are i.a. :
Talc 1: Micro Ace Type P3 having a volume average particle size of 4.5 μm and 1.29% by volume thereof having a size higher than 10 μm (commercially available from Nippon Talc, Interorgana Chemiehandel)
Talc 2: Mistton Ultramix having a volume average particle size of 3.88 μm and 1.72% by volume thereof having a size higher than 10 μm (commercially available from Cyprus Minerals)
Talc 3: Micro-talc I.T. Extra having a volume average particle size of 4.33μm and 2.43% by volume thereof having a size higher than 10 μm (commercially available from Norwegian Talc Minerals)
Talc 4: Cyprubond (surface-treated to improve adhesion to the binder) having a volume particle size of 5.28μm and 9.22% by volume thereof having a size higher than 10μm (commercially available from Cyprus Minerals).
Talc 5: MP10-52 having a volume particle size of 3.15μm and 1.26% by volume thereof having a size higher than 10μm (commercially available from Pfizer Minerals)
Talc 6: MP12-50 having a volume particle size of 2.60μm and 0.97% by volume thereof having a size higher than 10μm (commercially available from Pfizer Minerals)
Talc 7: Micro-talc A.T. Extra having a volume average particle size of 4.32μm and 3.76% by volume thereof having a size higher than 10 μm (commercially available from Norwegian Talc Minerals)
Talc 8: Stellar 600 having a volume average particle size of 5.16 μm and 6.77% by volume thereof having a size higher than 10 (commercially available from Norwegian Cyprus Minerals)
Examples of other silicate particles that can be used in accordance with the present invention are i.a. :
Silicate 1: Syloid 378, which are silica particles having an average particle size of 4μm and 0.06% by volume thereof having a size higher than 10μm (commercially available from Grace)
Silicate 2: Iriodin 111, which are mica particles having an average particle size of 4.42μm and 1.45% by volume thereof having a size higher than 10μm (commercially available from Merck)
Silicate 3: Chlorite, which is a magnesium-aluminium silicate having an average particle size of 5.57μm and 16.58% by volume thereof having a size higher than 10 μm (commercially available from Cyprus Minerals)
The binder for use in the protective layer in connection with the present invention is preferably polymeric and can be selected from amongst hydrophobic and hydrophilic binders. The latter are preferred in connection with the present invention since it has been found that less dirt forms on the thermal head during printing. The protective layer may also be hardened. Hardening may be carried out by means of UV or electron beam curing or the hardening may be effected using a chemical reaction between a hardening agent and the binder. Suitable hardening agents that can be used to harden a binder having active hydrogens are e.g. polyisocyanates, aldehydes and hydrolysed tetraalkyl orthosilicates.
Examples of binders that can be used in connection with the present invention are e.g. copolymers of styrene and acrylonitrile, copolymers of styrene, acrylonitrile and butadiene, nitrocellulose, copolymers of vinylacetate and vinylchloride which may be partially hydrolysed, polyesters and polycarbonates in particular those according to the following formula: ##STR1## wherein:
R 1 , R 2 , R 3 , and R 4 each independently represents hydrogen, halogen, a C 1 -C 8 alkyl group, a substituted C 1 -C 8 alkyl group, a C 5 -C 6 cycloalkyl group, a substituted C 5 -C 6 cycloalkyl group, a C 6 -C 10 aryl group, a substituted C 6 -C 10 aryl group, a C 7 -C 12 aralkyl group, or a substituted C 7 -C 12 aralkyl group; and
X represents the atoms necessary to complete a 5- to 8-membered alicyclic ring, optionally substituted with a C 1 -C 6 alkyl group, a 5- or 6-membered cycloalkyl group or a fused-on 5- or 6-membered cycloalkyl group.
Suitable hydrophilic binders for use in connection with the present invention include polyvinyl alcohol, polyvinyl acetate preferably hydrolysed in amount of 20% by weight or more, polyvinylpyrrolidone, gelatine etc.. The hydrophilic binder for use in the protective layer preferably has a weight average molecular weight of at least 20000 g/mol more preferably at least 30000 g/mol. According to a most preferred embodiment in connection with the present invention there is used a protective layer that contains a hydrolysed polyvinyl acetate hardened with a tetraalkyl orthosilicate.
In accordance with the present invention it is also preferred to add a lubricant to the protective layer or applying a lubricant on top of the protective layer. By using a lubricant transportation problems of the recording material under the thermal head can be avoided as well as image deformations. The lubricant is preferably used in an amount of 0.1% by weight to 10% by weight of the binder in the protective layer. Suitable lubricants for use in connection with the present invention are e.g. silicone oils, polysiloxane-polyether copolymers, synthetic oils, saturated hydrocarbons, glycols, fatty acids and salts or esters thereof such as e.g. stearic acid, the zinc salt of stearic acid, methyl ester of stearic acid etc. . .
According to a particular embodiment in connection with the present invention the lubricant may be hardened together with the binder of the protective layer. For example a binder having active hydrogens and a polysiloxane having active hydrogens may be hardened by means of e.g. polyisocyanate or a tetraalkyl orthosilicate yielding a hardened protective layer containing a lubricant.
The thickness of the protective layer in connection with the present invention is preferably between 1μm and 10μm, more preferably between 1.5μm and 7μm.
Substantially light-insensitive organic silver salts particularly suited for use according to the present invention are silver salts of aliphatic carboxylic acids known as fatty acids, wherein the aliphatic carbon chain has preferably at least 12 C-atoms, e.g. silver laurate, silver palmitate, silver stearate, silver hydroxystearate, silver oleate and silver behenate, and likewise silver dodecyl sulphonate described in U.S. Pat. No. 4,504,575 and silver di-(2-ethylhexyl)-sulfosuccinate described in published European patent application 227 141. Useful modified aliphatic carboxylic acids with thioether group are described e.g. in GB-P 1,111,492 and other organic silver salts are described in GB-P 1,439,478, e.g. silver benzoate and silver phthalazinone, which may be used likewise to produce a thermally developable silver image. Further are mentioned silver imidazolates and the substantially light-insensitive inorganic or organic silver salt complexes described in U.S. Pat. No. 4,260,677.
As binding agent for the heat sensitive layer preferably thermoplastic water insoluble resins are used wherein the ingredients can be dispersed homogeneously or form therewith a solid-state solution. For that purpose all kinds of natural, modified natural or synthetic resins may be used, e.g. cellulose derivatives such as ethylcellulose, cellulose esters, carboxymethylcellulose, starch ethers, polymers derived from α,β-ethylenically unsaturated compounds such as polyvinyl chloride, after-chlorinated polyvinyl chloride, copolymers of vinyl chloride and vinylidene chloride, copolymers of vinyl chloride and vinyl acetate, polyvinyl acetate and partially hydrolyzed polyvinyl acetate, polyvinyl alcohol, polyvinyl acetals, e.g. polyvinyl butyral, copolymers of acrylonitrile and acrylamide, polyacrylic acid esters, polymethacrylic acid esters and polyethylene or mixtures thereof. A particularly suitable ecologically interesting (halogen-free) binder is polyvinyl butyral. A polyvinyl butyral containing some vinyl alcohol units is marketed under the trade name BUTVAR B79 of Monsanto USA.
The binder to organic silver salt weight ratio is preferably in the range of 0.2 to 6, and the thickness of the image forming layer is preferably in the range of 5 to 16 μm.
The above mentioned polymers or mixtures thereof forming the binder may be used in conjunction with waxes or "heat solvents" also called "thermal solvents" or "thermosolvents" improving the penetration of the reducing agent(s) and thereby the reaction speed of the redox-reaction at elevated temperature.
By the term "heat solvent" in this invention is meant a non-hydrolyzable organic material which is in solid state at temperatures below 50° C. but becomes on heating above that temperature a plasticizer for the binder of the layer wherein they are incorporated and possibly act then also as a solvent for at least one of the redox-reactants, e.g. the reducing agent for the organic silver salt. Useful for that purpose are a polyethylene glycol having a mean molecular weight in the range of 1,500 to 20,000 described in U.S. Pat. No. 3,347,675. Further are mentioned compounds such as urea, methyl sulfonamide and ethylene carbonate being heat solvents described in U.S. Pat. No. 3,667,959, and compounds such as tetrahydro-thiophene-1,1-dioxide, methyl anisate and 1,10-decanediol being described as heat solvents in Research Disclosure, December 1976, (item 15027) pages 26-28. Still other examples of heat solvents have been described in U.S. Pat. No. 3,438,776, and 4,740,446, and in published EP-A 0 119 615 and 0 122 512 and DE-A 3 339 810.
Suitable organic reducing agents for the reduction of substantially light-insensitive organic silver salts are organic compounds containing at least one active hydrogen atom linked to O, N or C, such as is the case in aromatic di- and tri-hydroxy compounds, e.g. hydroquinone and substituted hydroquinones, catechol, pyrogallol, gallic acid and gallates; aminophenols, METOL (tradename), p-phenylenediamines, alkoxynaphthols, e.g. 4-methoxy-1-naphthol described in U.S. Pat. No. 3,094,417, pyrazolidin-3-one type reducing agents, e.g. PHENIDONE (tradename), pyrazolin-5-ones, indanedione-1,3 derivatives, hydroxytetrone acids, hydroxytetronimides, reductones, and ascorbic acid. Representatives for thermally activated reduction of organic silver salts are described e.g. in U.S. Pat. Nos. 3,074,809, 3,080,254, 3,094,417, 3,887,378 and 4,082,901.
Particularly suited organic reducing agents for use in thermally activated reduction of the substantially light insensitive silver salts are organic compounds containing in their structure two free hydroxy groups (-OH) in ortho-position on a benzene nucleus as is the case in catechol and polyhydroxy spiro-bis-indane compounds corresponding to the following general formula (I) which are preferred for use in the recording material according to the present invention: ##STR2## wherein: R represents hydrogen or alkyl, e.g. methyl or ethyl,
each of R 5 and R 6 (same or different) represents, an alkyl group, preferably methyl group or a cycloalkyl group, e.g. cyclohexyl group,
each of R 7 and R 8 (same or different) represents, an alkyl group, preferably methyl group or a cycloalkyl group, e.g. cyclohexyl group, and
each of Z 1 and Z 2 (same or different) represents the atoms necessary to close an aromatic ring or ring system, e.g. benzene ring, substituted with at least two hydroxyl groups in ortho- or para-position and optionally further substituted with at least one hydrocarbon group, e.g an alkyl or aryl group.
Particularly useful are the polyhydroxy-spiro-bis-indane compounds described in U.S. Pat. No. 3,440,049 as photographic tanning agent, more especially 3,3,3',3'-tetramethyl-5,6,5',6'-tetrahydroxy-1,1'-spiro-bis-indane (called indane I) and 3,3,3',3'-tetramethyl-4,6,7,4',6',7'-hexahydroxy-1,1'-spiro-bis-indane (called indane II) Indane is also known under the name hydrindene.
Preferably the reducing agent is added to the heat sensitive layer but all or part of the reducing agent may be added to one or more other layers on the same side of the support as the heat sensitive layer. For example, all or part of the reducing agent may be added to the protective surface layer.
The recording material may contain auxiliary reducing agents having poor reducing power in addition to the main reducing agent described above preferably in the heat sensitive layer containing the organic silver salt. For that purpose preferably sterically hindered phenols are used.
Sterically hindered phenols as described e.g. in U.S. Pat. No. 4,001,026 are examples of such auxiliary reducing agents that can be used in admixture with said organic silver salts without premature reduction reaction and fog-formation at room temperature.
For obtaining a neutral black image tone with silver formed in the higher optical density parts and neutral grey in the lower densities the reducible silver salt(s) and reducing agents are advantageously used in conjunction with a so-called toning agent known from thermography or photo-thermography.
Suitable toning agents are the phthalimides and phthalazinones within the scope of the general formulae described in U.S. Pat. No. 4,082,901. Further reference is made to the toning agents described in U.S. Pat. No. 3,074,809, 3,446,648 and 3,844,797. Particularly useful toning agents are likewise the heterocyclic toner compounds of the benzoxazine dione or naphthoxazine dione type.
According to the present invention an image can be obtained with the above described recording material by image-wise heating the recording material by moving the recording material under a thermal head, said thermal head contacting the protective layer. The recording material may be heated with a temperature of upto 400° C. by varying the number of heat pulses given by the thermal head. By varying the number of heat pulses the density of the corresponding image pixel is varied correspondingly.
The present invention will now be illustrated by the following examples without however the intention to limit the invention thereto. All parts are by weight unless otherwise specified.
EXAMPLE 1
Preparation of the recording materials:
A subbed polyethylene terephthalate support having a thickness of 100 μm was doctor blade-coated so as to obtain thereon after drying the following heat sensitive layer including:
______________________________________silver behenate 4.42 g/m.sup.2polyvinyl butyral 4.42 g/m.sup.2reducing agent S as defined hereinafter 0.84 g/m.sup.23,4-dihydro-2,4-dioxo-1,3,2H-benzoxazine 0.34 g/.sup.m2silicone oil 0.02 g/m.sup.2______________________________________
Reducing agent S is 1,1'-spirobi (1H-indene) -5,5',6,6'-tetrol-2,2',3,3'-tetrahydro-3,3,3',3'-tetramethyl.
To the heat sensitive layer was coated a protective layer having the following composition: T1 -polycarbonate (see below) 6 g/m 2 -matting agent (see TABLE 1) -Tegoglide 410* 0.3 g/m 2? -
The structure of the polycarbonate used was as follows: ##STR3## wherein x=55 mol % and y=45 mol %.
TABLE 1______________________________________Matting agentSample no. Type Diameter (μm) Amount (g/m.sup.2)______________________________________1 -- -- --2 Tospearl 145 4.5 0.183 PMMA 6 0.06______________________________________
PMMA=copolymer of styrene, methylmethacrylate, stearyl methacrylate, maleinic acid sodium salt and 2-trimethoxysilylethy methacrylate.
Tospearl 145 (tradename) is a silicone resin particle
The recording materials prepared as described above were image-wise heated with a thermal head in a thermal printer so as to obtain a density of 3.2. The obtained minimum density in each case was less than 0.05. The obtained images were then visually inspected for scratches and assigned a number from 0 to 5 to indicate the amount of scratches. A number of 0 indicates that no scratches were found whereas a number of 5 indicates severe scratching of the image. The obtained results are listed in table 2.
TABLE 2______________________________________ Sample no. Scratches______________________________________ 1 5 2 1 3 3______________________________________
From the above table it can be seen that the number of scratches on the image can be effectively reduced by adding a matting agent to the protective layer.
EXAMPLE 2
A recording material was prepared similar to the recording materials of example 1 with the exception however that the protective layer was replaced with a layer having the following composition:
______________________________________polyvinyl alcohol 3.5 g/m.sup.2China Clay (matting agent) 1.5 g/m.sup.2______________________________________
The polyvinyl alcohol used was POLYVIOL W48/20 obtained from Wacker.
The thus obtained recording material was printed and evaluated as in example 1. A number of 1 could be assigned to indicate the amount of scratches. Furthermore it was found that no contamination of the thermal head occured.
EXAMPLE 3
A recording material was prepared as described in example 2 with the exception that on top of the protective layer there was applied a thin layer of Tegoglide 410 (lubricant) in an amount of 18 mg/m 2 . A number of 0 to 1 could be assigned to indicate that practically no scratches were found. Furthermore it was found that no contamination of the thermal head occured.
EXAMPLE 4
2 parts of a solution in water containing 7% of polyvinyl alcohol (POLYVIOL W48/20 from Wacker) and 3% of China Clay were mixed with 1 part of an aqueous solution containing 14% of tetramethyl orthosilicate. The mixture was brought to pH=4 using sodium hydroxide.
The obtained solution was coated with a Braive knife of 50μm to a polyethyleneterephthalate support containing the heat sensitive layer described in example 1. The obtained recording material was dried and heated for 1 hour at 60° C. to harden the protective layer.
The recording material was then printed and evaluated as described in example 1. No scratches were found on the image. Furthermore it was found that no contamination of the thermal head occured. | The present invention provides a recording material comprising on a support (i) a heat sensitive layer comprising a substantially light insensitive organic silver salt, (ii) a protective layer containing a matting agent dispersed in a binder and (iii) a reducing agent being present in the heat sensitive layer and/or another layer on the same side of the support carrying the heat sensitive layer. The present invention further provides a method for making images therewith. The obtained images may be used in medical diagnostics. | 1 |
This application is a continuation of Ser. No. 09/157,208, filed Sep. 18, 1998, now U.S. Pat. No. 6,280,504.
BACKGROUND OF THE INVENTION
The present invention relates to dehumidifiers. More particularly, the present invention relates to a hygroscopic material having a shape and surface area orientation which facilitates circulation and drying of a working gas.
Dehumidifiers are used to dry working gases, such as water vapor in air. Typical desiccant dehumidifying machines blow the air or working gas across a desiccant material to remove the vapor from the working gas. These types of machines require a power source and typically utilize moving parts to dry the working space. In addition, the desiccant is typically contained or packaged within the machine and the vapor rich air is mechanically passed across the desiccant. In addition to requiring active intervention to turn the machine ON and OFF, such devices are limited by their power needs, the breakdown of the moving mechanical components, and a somewhat inefficient use of the desiccant material.
SUMMARY OF THE INVENTION
Accordingly, the present invention provides a shaped monolithic hygroscopic material which moves air through a “chimney effect” or air density differences in and around the material. The present invention thus provides a passive dehumidifier which allows direct contact with the gas being dried without the need for an outside power source, moving parts, or packaging of a desiccant material. Alternatively, the tendency of the material to seek equilibrium with the working gas may also be utilized to achieve humidification.
The present invention comprises a hygroscopic material having at least one passageway or channel therethrough. The material is shaped to provide a surface area to facilitate gas flow, and drying of an ambient gas by creating a chimney effect which facilitates mixing of the gas. This causes the heavier water vapor or other compound containing gas to contact adsorbent material adjacent to the passageway or channel, adsorb at least some of the compound, and cause the lighter gas to exit the passageway or channel. The dehumidifier may have various shapes and sizes and can be reactivated to restore its drying capacity. When utilized as a humidifier, the material desorbs or adds the constituent (such as water vapor) to the gas and a downdraft rather than a chimney effect is achieved.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is a side view of one embodiment of the present invention illustrating flow of air or other gas therethrough.
FIG. 2 is a phantom view of FIG. 1 .
FIG. 3 is a cross-sectional view taken along section lines 3 — 3 of FIG. 2 .
FIG. 4 is a perspective view of an alternate embodiment of the present invention illustrating air or other gas flow therethrough.
FIG. 5 is a top view of FIG. 4 .
FIG. 6 is a cross sectional view taken along section lines 6 — 6 of FIG. 4 .
FIG. 7 is a perspective view of a further alternate embodiment of the present invention illustrating air or other gas flow therethrough.
FIG. 8 is a top view of FIG. 7 .
FIG. 9 is a cross sectional view taken along section lines 9 — 9 of FIG. 7 .
FIG. 10 is a side view of an embodiment of the present invention utilized as a humidifier and illustrating alternate flow of air or other gas therethrough.
FIG. 11 is a graph illustrating the data reflected in Table 1.
FIG. 12 is a graph illustrating the data reflected in Table 2.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to FIG. 1, FIG. 2 and FIG. 3, an embodiment of the present invention is identified by the number 14 . For purposes of the present description, it will be described in connection with its usage as a dehumidifier 14 . The dehumidifier 14 comprises a shaped, monolithic hygroscopic material 16 . The material 16 has a plurality of external surface areas which include a plurality of generally square external surfaces 18 and a plurality of generally triangular external surfaces 20 . The material 16 has a generally polyhedron or faceted shape.
As further illustrated in FIG. 2, the material 16 has a plurality of channels or passageways 22 therethrough. Each passageway 22 has an inlet port and an outlet port, identified generally by the number 24 . Depending upon the orientation of the material 16 , any port 24 may function as an inlet port or outlet port. As illustrated in FIG. 3, each passageway 22 has an internal surface 26 . Each passageway 22 is generally cylindrical, passes from one side of material 16 to an opposite side, and has a plurality of other passages 22 in fluid communication with and generally perpendicular thereto.
Referring again to FIG. 1, the usage and operation of the dehumidifier 14 will be described in greater detail. The dehumidifier 14 may be placed in any environment having water vapor or other compound or constituent (for which dehumidifier 14 has an affinity) within a working gas, such as air. When the heavier, denser compound/vapor laden gas (dotted arrows) enters an inlet port 24 it is dried by the surface area 26 of the adsorbent material 16 within the corresponding passageway 22 . The lighter, drier air (clear arrows) thereafter exits through a port 24 . As the dry air rises, a circulation or “chimney” effect is created within the working environment, as illustrated by the arrows in FIG. 1 . That is, the lighter, drier air rises from the dehumidifier 14 and the heavier, vapor laden air is circulated to enter the dehumidifier 14 (passages 22 ) so that the water vapor or other constituent of the gas is adsorbed (or absorbed) by material 16 . Surfaces 18 and 20 may also provide some adsorption (or absorption) of the gaseous constituent.
Testing of the embodiment of FIG. 1 yielded the results reflected in Table 1, as graphically depicted in FIG. 11 . In the test, a dehumidifier 14 having a mass of approximately 10 grams (natural zeolite) was activated (dried) in a microwave oven and placed in a sealed, one liter glass beaker with a probe for measuring temperature (degrees Fahrenheit), relative humidity (% Rh), dewpoint (degrees Fahrenheit), and absolute humidity (grains per pound). Readings of the probe were taken every thirty seconds. As evidenced by the data collected, the dehumidifier 14 rapidly and efficiently dried the air in the beaker.
TABLE 1
Dehumidification Data, 1 liter air volume, 30 sec interval
Relative
Dewpoint
Absolute
Humidity
Temp
Temp.
Humidity
Time
Rh
T
Td
x
t
A
B
C
D
E
1
57.1
75.5
59.4
75.4
0
2
30.2
75.5
40.6
36
0.5
3
23.8
75.5
35.4
29.6
1
4
15.7
75.6
25.7
19.6
1.5
5
11.8
75.6
18.8
15.1
2
6
8.9
75.7
12.4
11.6
2.5
7
7.1
75.7
7.5
9.15
3
8
5.8
75.7
3.1
7.4
3.5
9
4.8
75.8
−0.9
6.16
4
10
4.1
75.8
−4.4
5.16
4.5
11
3.5
75.8
−7.3
4.55
5
12
3.1
75.8
−9.9
4
5.5
13
2.7
75.8
−12.4
3.56
6
14
2.4
75.9
−14.6
3.14
6.5
15
2.2
75.9
−16.3
3.09
7
16
2
75.9
−18.1
2.68
7.5
17
1.8
75.9
−19.9
2.4
8
18
1.7
75.9
−21
2.26
8.5
19
1.6
75.9
−22.4
2.1
9
20
1.5
75.9
−23.7
1.98
9.5
21
1.4
76
−24.6
1.88
10
22
1.3
76
−25.7
1.77
10.5
23
1.3
76
−26.6
1.67
11
24
1.2
76
−27.6
1.59
11.5
25
1.1
76
−28.6
1.5
12
26
1.1
76
−29.4
1.45
12.5
27
1
76.1
−30.3
1.39
13
28
1
76.1
−31
1.31
13.5
29
1
76.1
−31.6
1.31
14
30
0.9
76.1
−32.5
1.23
14.5
31
0.9
76.1
−33.2
1.16
15
32
0.9
76.1
−33.8
1.14
15.5
33
0.8
76.1
−34.3
1.08
16
34
0.8
76.1
−35
1.06
16.5
35
0.8
76.1
−35.4
1.04
17
36
0.8
76.1
−36
0.99
17.5
37
0.7
76.1
−36.5
0.98
18
38
0.7
76.1
−37
0.94
18.5
39
0.7
76.1
−37.6
0.91
19
40
0.7
76.1
−38
0.88
19.5
41
0.6
76.1
−38.6
0.86
20
42
0.6
76.1
−39
0.83
20.5
43
0.6
76.1
−39.7
0.81
21
44
0.6
76.1
−40
0.77
21.5
45
0.6
76.1
−40.5
0.76
22
46
0.6
76.1
−41
0.74
22.5
47
0.5
76.1
−41.4
0.72
23
48
0.5
76.1
−41.8
0.71
23.5
49
0.5
76.1
−42
0.69
24
50
0.5
76.1
−42.4
0.67
24.5
51
0.5
76.1
−43
0.66
25
52
0.5
76.1
−43.3
0.65
25.5
53
0.5
76.1
−43.7
0.63
26
54
0.5
76.1
−44.2
0.61
26.5
55
0.5
76.1
−44.6
0.6
27
56
0.4
76.1
−45
0.59
27.5
57
0.4
76.2
−45.3
0.58
28
58
0.4
76.2
−45.8
0.56
28.5
59
0.4
76.2
−46
0.55
29
60
0.4
76.2
−46.2
0.54
29.5
61
0.4
76.2
−46.8
0.53
30
62
0.4
76.2
−47
0.51
30.5
63
0.4
76.2
−47.3
0.5
31
64
0.4
76.2
−47.7
0.5
31.5
65
0.4
76.2
−48
0.49
32
66
0.4
76.2
−48.4
0.48
32.5
67
0.3
76.2
−48.7
0.47
33
68
0.3
76.2
−49
0.45
33.5
69
0.3
76.2
−49.4
0.45
34
70
0.3
76.2
−49.9
0.43
34.5
71
0.3
76.2
−50
0.42
35
72
0.3
76.2
−50.8
0.41
35.5
73
0.3
76.2
−51
0.4
36
74
0.3
76.2
−51.6
0.39
36.5
75
0.3
76.2
−51.8
0.39
37
76
77
0.2
76.2
−60.7
0.22
61.5
78
0.2
76.2
−61
0.21
89.5
Referring to FIG. 4, FIG. 5 and FIG. 6, an alternate embodiment of the present invention is identified by the number 30 . For purposes of the present description, it will be described in connection with its usage as a dehumidifier 30 . The dehumidifier 30 comprises a shaped, monolithic hygroscopic material 32 . The material 32 has a plurality of generally rectangular columns 34 which define a plurality of external channels 36 therein. Each channel 36 has internal surfaces 38 . Channels 36 extend the length L, width W, and depth D of dehumidifier 30 and the length L is generally twice the width W and twice the depth D with the width W and depth D being approximately equal. The material 32 has a generally columnar shape, a plurality of generally square external surfaces 40 and a plurality of generally rectangular external surfaces 42 .
Referring again to FIG. 5 and FIG. 6, the material 32 further comprises a cylindrical internal passageway 44 therethrough. Passageway 44 has an inlet port 45 on a first lengthwise end of dehumidifier 30 and an outlet port 46 on a second, opposite lengthwise end of dehumidifier 30 . Passageway 44 extends from channel 36 on one lengthwise end of dehumidifier 30 to channel 36 on the opposite lengthwise end and has an internal surface 48 . As may be readily understood, ports 44 and 45 may each serve as an inlet port and an outlet port, depending upon the orientation of the dehumidifier 30 .
Referring again to FIG. 4, the usage and operation of the dehumidifier 30 will be described in greater detail. The dehumidifier 30 may be placed in any environment having water vapor or other compound or constituent (for which dehumidifier 30 has an affinity) within a working gas, such as air. When the heavier, denser compound/vapor laden gas (dotted arrows) enters the channels 36 it is dried by the surface area 38 of the adsorbent material 32 within the corresponding channel 36 . The lighter, drier air (clear arrows) thereafter exits the respective channel 36 . Likewise, heavier, denser compound/vapor laden gas (dotted arrows) enters inlet port 45 and is dried by the surface area 48 of the adsorbent material 32 within passageway 44 . The lighter, drier air (clear arrows) thereafter exits through exit port 46 . As the dry air from channels 36 and passage 44 rises, a circulation or “chimney” effect is created within the working environment, as illustrated by the arrows in FIG. 4 . That is, the lighter, drier air rises from the dehumidifier 30 and the heavier, vapor laden air is circulated to enter the dehumidifier 30 (channels 36 and passage 44 ) so that the water vapor or other constituent of the gas is adsorbed (or absorbed) by material 32 . Surfaces 40 and 42 may also provide some adsorption (or absorption) of the gaseous constituent.
Testing of the embodiment of FIG. 4 yielded the results reflected in Table 2, as graphically depicted in FIG. 12 . In the test, a dehumidifier 30 having a mass of approximately 40 grams (natural zeolite) was activated (dried) in a microwave oven and placed in a sealed one liter glass beaker with a probe for measuring temperature (degrees Fahrenheit), relative humidity (% Rh), dewpoint (degrees Fahrenheit), and absolute humidity (grains per pound). Readings of the probe were taken every thirty seconds. As evidenced by the data collected, the dehumidifier 30 rapidly and efficiently dried the air in the beaker.
TABLE 2
Dehumidification Data, 1 liter air volume, 30 sec interval
Relative
Dewpoint
Absolute
Humidity
Temp
Temp.
Humidity
Time
Rh
T
Td
X
t
A
B
C
D
E
1
51.1
68.2
49.4
52.2
0
2
38.7
68.5
41.8
38.5
0.5
3
33.7
68.6
38.5
33.9
1
4
28.3
68.8
34.4
28.9
1.5
5
23.3
68.8
29.8
24
2
6
20.3
68.9
26.3
20.7
2.5
7
17.4
69
22.8
17.9
3
8
15.7
69.1
20.5
16.2
3.5
9
13.6
69.2
17.3
14.2
4
10
12.4
69.3
15.1
12.9
4.5
11
11.3
69.3
13.3
11.9
5
12
10.5
69.4
11.5
11
5.5
13
9.7
69.5
9.8
10.2
6
14
8.9
69.6
8.3
9.51
6.5
15
8.4
69.7
6.6
8.82
7
16
7.9
69.7
5.5
8.4
7.5
17
7.4
69.8
4.3
7.91
8
18
7
69.9
3
7.48
8.5
19
6.6
69.9
1.9
7.09
9
20
6.3
70
1
6.76
9.5
21
6
70.1
0
6.48
10
22
5.8
70.2
−0.9
6.2
10.5
23
5.5
70.2
−1.9
5.93
11
24
5.2
70.3
−2.8
5.67
11.5
25
5
70.4
−3.6
5.45
12
26
4.8
70.4
−4.4
5.26
12.5
27
4.7
70.5
−5.1
5.08
13
28
4.5
70.5
−5.8
4.89
13.5
29
4.3
70.5
−6.5
4.73
14
30
4.2
70.6
−7.2
4.57
14.5
31
4
70.6
−7.9
4.43
15
32
3.2
70.5
−13
3.43
20
33
2.7
70
−16.1
2.93
25.5
34
2.5
70.1
−18.1
2.66
30.5
35
2.3
70.6
−19.4
2.49
40.5
36
1.3
70.3
−29.6
1.42
65.5
Referring to FIG. 7, FIG. 8 and FIG. 9, another embodiment of the present invention is identified by the number 50. For purposes of the present description, it will be described in connection with its usage as a dehumidifier 50 . The dehumidifier 50 comprises a shaped, monolithic hygroscopic material 52 . The material 52 has a plurality of external surface areas which include a plurality of generally square external surfaces 54 and a plurality of generally rectangular surface areas 56 .
As further illustrated in FIG. 7 and FIG. 8, the material 52 has a plurality of channels 58 therein. Each channel 58 has internal surfaces 60 . Channels 58 extend the length L, width W, and depth D of dehumidifier 50 with the length L, width W and depth D being approximately equal so as to form a generally cubed shape.
Referring again to FIG. 8 and FIG. 9, the material 52 has a plurality of passageways 62 therethrough. Each passageway 62 has an inlet port and an outlet port, identified by the number 64 . Depending upon the orientation of the material 52 , any port 64 may function as an inlet port or outlet port. Each passageway 62 has an internal surface 66 . Each passageway 62 is generally cylindrical, passes from one side of material 52 to an opposite side, and it has a plurality of other passages 62 in fluid communication with and generally perpendicular thereto.
Referring again to FIG. 7, the usage and operation of the dehumidifier 50 will be described in greater detail. The dehumidifier 50 may be placed in any environment having water vapor or other compound or constituent (for which dehumidifier 50 has an affinity) within a working gas, such as air. When the heavier, denser compound/vapor laden gas (dotted arrows) enters an inlet port 64 , it is dried by the surface area of the adsorbent or hygroscopic material 52 within the corresponding passageway 62 . The lighter, drier air (clear arrows) thereafter exits through a port 64 . As the dry air rises, a circulation or “chimney” effect is created within the working environment, as illustrated by the arrows in FIG. 7 . That is, the lighter, drier air rises from the dehumidifier 50 and the heavier, vapor laden air is circulated to enter the dehumidifier 50 (through channels 58 or passages 62 ) so that the water vapor or other constituent of the gas is adsorbed (or absorbed) by material 52 . Surfaces 54 and 56 may also provide some adsorption (or absorption) of the gaseous constituent.
It is to be understood that the dehumidifiers 14 , 30 , and 50 may be constructed of various shapes and sizes depending upon the working space to be dried. Further, the dehumidifiers 14 and 50 may be “tossed” into an enclosed space, such as a case, and will always land and sit “upright” regardless of how they land. That is, the orientation of the dehumidifiers 14 and 50 is always consistent and appropriate regardless of which “side” they rest upon. It is also to be understood that the material 16 , 32 and 52 may be natural zeolite and that the dehumidifiers of the present invention may be useful in archival of museum, photographic, and other environmentally sensitive material, and protective storage of industrial equipment, and any generally enclosed space in which the humidity or concentration of a gaseous compound is of concern. The material 16 , 32 and 52 may be shaped and the channels and passages within the material 16 , 32 and 52 may be formed by machining, extruding or pressing.
The present invention thus also provides a process for dehumidifying a gas in an enclosed space, comprising the steps of forming a hygroscopic or adsorbent material into a shape which may be received within the space and to circulate and dry the gas in a desired manner, such as by the chimney effect described herein, activating or otherwise preparing or conditioning the material, such as by drying, and placing the material within the enclosed space. When the material has dried or otherwise adsorbed a sufficient or maximum amount of compound, it may be removed from the enclosed space, reactivated through further drying, and replaced within the enclosed space for additional drying of the space. Alternatively, the material may be reactivated or dried within the enclosed space without removal therefrom.
It is to be appreciated that the hygroscopic monolith of the present invention will seek equilibrium with the compound or constituent laden gas within the working space, such activity being facilitated by the shape and surface area of the monolith so as to passively interact with the gaseous environment. As such, the hygroscopic monolith of the present invention may also be used to humidify or otherwise provide a gaseous compound or constituent to a working space. The monolith is charged or conditioned by saturating the monolith with the water or other compound or constituent and placing it within the space having a drier humidity or other ability or affinity to cause the water or other compound/constituent to mix with the gas. In this environment, a downdraft, rather than a chimney effect, is created. As illustrated in FIG. 10, the dehumidifier 14 may be utilized as a humidifier 14 A such that the drier air (clear arrows) enters the humidifier 14 A (passages 22 ) and water vapor or other compound or constituent is adsorbed by the gas and flows outward from the humidifier 14 A (dotted arrows). Similar results can be obtained by saturating the hygroscopic material of FIG. 4 or FIG. 7 .
It is to be understood that the present invention provides the ability to facilitate the chimney effect or downdraft effect provided by the hygroscopic monolith so as to modify the composition of a gas in an enclosed space and in a desired manner. For example, when dehumidification is desired, a greater surface area but smaller mass of the hygroscopic material generally results in a quicker drying but less drying capacity. Likewise, a smaller surface area but a greater mass generally provides slower drying but a greater drying capacity. Also, when used as a dehumidifier, the hygroscopic monolith of the present invention is preferably placed in the bottom of an enclosure and when used as a humidifier, it is preferably placed in the top of an enclosure. It is also to be understood that the channels and passageways in the hygroscopic monolith provide a high surface to volume ratio and may be positioned to facilitate air density differences in and around the monolith in the manner described herein.
While the hygroscopic monolith of the present invention has been described in connection with preferred embodiments, it is not intended to limit the invention to the particular form set forth, but on the contrary, it is intended to cover such alternatives, modifications, and equivalents as may be included within the spirit and scope of the invention as defined by the appended claims. | A monolithic hygroscopic material shaped to facilitate a circulation flow of ambient air. The hygroscopic material may be used to remove various compounds from an ambient gas and may be reactivated to restore its drying capacity. The tendency of the material to seek equilibrium may be utilized to achieve dehumidification or humidification. | 1 |
FIELD OF THE INVENTION
[0001] This invention is in the field of methods and apparatus for isolating one formation zone of an oil or gas well bore from another zone.
BACKGROUND OF THE INVENTION
[0002] It is common to drill an oil or gas well bore into and through several different formation zones, where the zones are layered vertically. In such cases, it is typical to isolate each zone from the zones above and below it by installing a packer in the well bore between zones, surrounding a tubular element, such as production piping, which is used to access the various zones. Known systems for achieving this isolation commonly use inflatable or mechanically expandable packers. The inflated packers can be filled with various fluids or even cement. These types of packers can be expensive, and setting them in place can be complicated, since electrical or mechanical systems are usually required for the setting operation. These packers are also less effective in open hole applications than in cased hole applications, because they sometimes do not truly conform to the irregular walls of the open hole, resulting in a limited pressure seal capacity. The problems of expense and complexity are even greater in an application where numerous zones are being accessed by a multi-purpose tool having numerous perforation sections for production of fluid from the well or injection of fluid into the well. This is because numerous packers are required to isolate between zones, and because operation of the numerous perforation sections adds to the overall complexity of operating such a tool.
BRIEF SUMMARY OF THE INVENTION
[0003] The present invention is a method and apparatus for isolating between zones with a packer. In the preferred embodiment the packer constructed of memory based material, such as a memory based foam, where the multiple zones are accessed by means of radially telescoping perforation elements. The memory based material is formed onto a base element, such as a mandrel or another tubular element, to form a packer with an outer diameter slightly larger than the downhole diameter in which the packer will be used. The packer is positioned between two sections of radially telescoping perforation elements, in a downhole tool. Two or more packers can be arranged between three or more sections of radially telescoping perforation elements. The memory based material is compressed, such as by elevating a memory based foam to a temperature at which it begins to soften, sometimes called the transition temperature, and the outside diameter of the memory based material is reduced to a smaller diameter, such as by being compressed. Once compressed, the memory based material is then stabilized at that smaller diameter, such as by cooling a memory based foam below the transition temperature, causing it to harden at this desired, smaller, run-in diameter. Then, the tool is run into the hole on a tubular work string, placing each packer at a depth where zonal isolation is required, and placing each section of radially telescoping perforation elements at a depth where zonal access is required. Once each packer is at its respective required zonal isolation depth, the memory based material is then expanded, such as by raising a memory based foam above the transition temperature, causing it to tend to return to its original, larger, outer diameter. Since the original diameter is larger than the hole diameter, the packer conforms to the bore hole and exerts an effective pressure seal on the bore hole wall, between zones. As an alternative, the mandrel or other base element can be hollow, and it can be expanded either before, during, or after the temperature-induced expansion of the foam expansion element. This expansion can be achieved by a mechanical, hydraulic, or hydro-mechanical device. Expansion of the mandrel can enhance the overall expansion achieved with a given amount of memory based material expansion, and it can increase the resultant pressure exerted by the memory based expansion element on the borehole wall, thereby creating a more effective seal. Different packers can be adapted to expand at different temperatures, or through other means adapted to expand at different selected times, as desired by the operator. If desired, cementing of the annulus can also be performed, in the normal fashion. Other alternatives to shape memory packers are envisioned for sealing producing zones such as mechanically or hydraulically set packers, inflatable packers, barriers made of a hardenable material and other designs used downhole to isolate one portion of the wellbore from another.
[0004] The novel features of this invention, as well as the invention itself, will be best understood from the attached drawings, taken along with the following description, in which similar reference characters refer to similar parts, and in which:
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
[0005] FIG. 1 is a perspective view of the preferred memory based packer invention, in its originally formed size and shape and is intended to schematically illustrate the use of alternative barriers in the present invention;
[0006] FIG. 2 is a perspective view of the apparatus shown in FIG. 1 , reduced to its interim size and shape;
[0007] FIG. 3 is a perspective view of the apparatus shown in FIG. 1 , expanded to seal against the borehole wall;
[0008] FIGS. 4 and 5 are partial section views of the memory based packer of the present invention, implementing a hydro-mechanical device to expand the mandrel;
[0009] FIGS. 6 and 7 are partial section views of the memory based packer of the present invention, implementing a mechanical device to expand the mandrel;
[0010] FIG. 8 is a partial section view of the memory based packer of the present invention, implementing a hydraulic device to expand the mandrel;
[0011] FIGS. 9 and 10 show a first embodiment of the invention incorporating a memory based packer with a telescoping perforation tool having a solid walled shifting sleeve, some sand control elements, and some fracturing elements;
[0012] FIGS. 11 and 12 show a second embodiment of the invention incorporating a memory based packer with a telescoping perforation tool having a shifting sleeve incorporating a sand control medium, where none of the telescoping elements have a sand control medium;
[0013] FIGS. 13 and 14 show a third embodiment of the invention incorporating a memory based packer with a telescoping perforation tool having a shifting sleeve with ports, some sand control elements, and some fracturing elements; and
[0014] FIGS. 15 and 16 show a fourth embodiment of the invention incorporating a memory based packer with a telescoping perforation tool having a shifting sleeve with some sand control ports, and some fracturing ports.
DETAILED DESCRIPTION OF THE INVENTION
[0015] As shown in FIG. 1 , the preferred packer for use in the present invention is a memory based packer 10 having a base element, such as a tubular element or a mandrel 20 , on which is formed a memory based expansion element 30 , such as an element constructed of memory based foam. The mandrel 20 can be any desired length or shape, to suit the desired application, and it can be hollow if required. It can also have any desired connection features, such as threaded ends. The mandrel 20 can be a portion of the tubular body of the overall tool, or it can be a separate tubular element. The expansion element 30 is shown with a cylindrical shape, but this can be varied, such as by means of concave ends or striated areas (not shown), to facilitate deployment, or to enhance the sealing characteristics of the packer. The expansion element 30 is composed of a memory based material, for example, an elastic memory foam such as Tembo™ foam, an open cell syntactic foam manufactured by Composite Technology Development, Inc. This type of foam has the property of being convertible from one size and shape to another size and/or shape, by changing the temperature of the foam. This type of foam can be formed into an article with an original size and shape as desired, such as a cylinder with a desired outer diameter. The foam article thusly formed is then heated to raise its temperature to its transition temperature. As it achieves the transition temperature, the foam softens, allowing the foam article to be reshaped to a desired interim size and shape, such as by being compressed to form a smaller diameter cylinder. The temperature of the foam article is then lowered below the transition temperature, to cause the foam article to retain its interim size and shape. When subsequently raised again to its transition temperature, the foam article will return to its original size and shape.
[0016] In the present invention, the cylindrical memory based expansion element 30 can be originally formed onto the mandrel 20 by wrapping a blanket of the memory based material onto the mandrel 20 , with the desired original outer diameter OD 1 . Alternatively, the process for forming the expansion element 30 on the mandrel 20 can be any other process which results in the expansion element 30 having the desired original diameter, such as by molding the memory based material directly onto the mandrel 20 . The desired original outer diameter OD 1 is larger than the bore hole diameter BHD (shown for reference in FIG. 1 ) in which the packer 10 will be deployed. For instance, an expansion element 30 having an original outer diameter OD 1 of 10 inches might be formed for use in an 8.5 inch diameter borehole.
[0017] Then, the memory based packer is reduced in diameter, for example by raising the temperature of the expansion element 30 above the transition temperature of the memory based foam material, which causes the foam to soften. At this point, the expansion element 30 is compressed to a smaller interim outer diameter OD 2 . For instance, the expansion element 30 might be compressed to an interim outer diameter OD 2 of 7.5 inches for use in an 8.5 inch diameter borehole. This facilitates running the packer 10 into the borehole. This type of foam may be convertible in this way to an interim size and shape approximately one third the volume of the original size and shape. After compression, the expansion element 30 is lowered below its transition temperature, causing it to retain its smaller interim outer diameter OD 2 . This cooling step can be achieved by exposure to the ambient environment, or by exposure to forced cooling.
[0018] After this diameter reduction, the memory based packer 10 is lowered into the borehole to the desired depth at which zonal isolation is to occur, as shown in FIG. 2 . Once the packer 10 is located at the desired depth for isolating the borehole, the expansion element 30 is again expanded, such as by being raised to the transition temperature of the foam. As shown in FIG. 3 , this causes the expansion element 30 to expand to a final outer diameter OD 3 . Because of the properties of the elastic memory foam, the expansion element 30 attempts to return to the original outer diameter OD 1 . However, since the original outer diameter OD 1 was selected to be larger than the borehole diameter BHD, the expansion element 30 can only expand until the final outer diameter OD 3 matches the borehole diameter BHD. This can cause the expansion element 30 to exert a pressure of between 300 and 500 psi on the borehole wall.
[0019] The memory based packer can be adapted to selectively expand at different times; for example, where memory based foam is used, the foam material composition can be formulated to achieve the desired transition temperature. This quality allows the foam to be formulated in anticipation of the desired transition temperature to be used for a given application. For instance, in use with the present invention, the foam material composition can be formulated to have a transition temperature just slightly below the anticipated downhole temperature at the depth at which the packer 10 will be used. This causes the expansion element 30 to expand at the temperature found at the desired depth, and to remain tightly sealed against the bore hole wall. Downhole temperature can be used to expand the expansion element 30 ; alternatively, other means can be used, such as a separate heat source. Such a heat source could be a wireline deployed electric heater, or a battery fed heater. For example, such a heat source could be mounted to the mandrel 20 , incorporated into the mandrel 20 , or otherwise mounted in contact with the foam expansion element 30 . The heater could be controlled from the surface of the well site, or it could be controlled by a timing device or a pressure sensor. Still further, an exothermic reaction could be created by chemicals pumped downhole from the surface, or heat could be generated by any other suitable means. Also, on a tool where several packers 10 are employed, each packer can be formulated to expand at a different temperature, giving the operator individual control of the expansion of each packer.
[0020] As an alternative, if it is desired to enhance the overall amount of packer expansion achievable, in addition to the expansion achievable with a given volume of memory based material, the mandrel 20 itself can be a hollow base element which can be expanded radially. This additional expansion can be achieved by the use of a mechanical, hydraulic, or hydro-mechanical device. For example, as shown in FIG. 4 , a hydro-mechanical expander 40 can be run into the tubing on a work string, either before, during, or after the memory based expansion of the material. The hydro-mechanical expander 40 can consist essentially of an anchoring device 42 , a hydraulic ram 44 , and a conical pig 46 . Once the conical pig 46 reaches the mandrel 20 , the anchoring device 42 is activated to anchor itself to the tubing. Activation of the anchoring device 42 can be mechanical, electrical, or hydraulic, as is well known in the art. Once the expander 40 is thusly anchored in place, the hydraulic ram 44 can be pressurized to force the conical pig 46 into and through the mandrel 20 of the packer 10 , as shown in FIG. 5 . Since the outer diameter of the conical pig 46 is selected to be slightly larger than the inner diameter of the mandrel 20 , as the conical pig 46 advances through the mandrel 20 , it radially expands the mandrel 20 .
[0021] As mentioned above, this expansion of the mandrel 20 can be implemented before, during, or after the memory based expansion of the expansion element 30 . It can be seen that radial expansion of the mandrel 20 in this way can enhance the overall expansion possible with the packer 10 . Therefore, for a given amount of memory based material in the expansion element 30 , the final diameter to which the packer 10 can be expanded can be increased, or the pressure exerted by the expanded packer 10 can be increased, or both. For example, a relatively smaller overall diameter packer 10 can be run into the hole, thereby making the running easier, with mandrel expansion being employed to achieve the necessary overall expansion. Or, a relatively larger overall diameter packer 10 can be run into the hole, with mandrel expansion being employed to achieve a higher pressure seal against the borehole wall.
[0022] As a further alternative to use of the hydro-mechanical expander 40 , the mandrel 20 can be expanded by mechanically forcing a conical pig 50 through the mandrel 20 with a work string, as shown in FIGS. 6 and 7 . Forcing of the pig 50 through the mandrel 20 can be either by pushing with the work string, as shown in FIG. 6 , or by pulling with the work string, as shown in FIG. 7 . Still further, the mandrel 20 can be expanded by hydraulically forcing a conical pig 60 through the mandrel 20 with mud pump pressure, as shown in FIG. 8 .
[0023] While memory based packers are preferred, other barriers used downhole to isolate one portion of the wellbore from another can be used as alternatives. These barriers can be mechanically or hydraulically set packers, inflatables, or materials that can be deposited in an annular space and become firm barriers such as, for example, cement.
[0024] The present invention provides one or more memory based packers 10 between two or more sections of radially telescoping perforating elements, for selectively perforating a well bore liner, fracturing a formation, and producing or injecting fluids, sand-free. Examples of such tools are shown in FIGS. 9 through 16 . In each of these, the memory based packers 10 are mounted on a tubular tool body having a plurality of radially outwardly telescoping tubular elements. The radially telescoping tubular elements are grouped in two or more groups, separated vertically, to align with the various zones of the formation in which the tool will be used. Packers can be provided between the groups of telescoping tubular elements. A mechanical means can be provided for selectively controlling the hydrostatic fracturing of the formation through one or more of the telescoping elements and for selectively controlling the sand-free injection or production of fluids through one or more of the telescoping elements. Selective expansion of the memory based packers 10 is as described above.
[0025] The apparatus can have a built-in sand control medium in one or more of the telescoping elements, to allow for injection or production, and a check valve in one or more of the telescoping elements, to allow for one way flow to hydrostatically fracture the formation without allowing sand intrusion after fracturing. Vertical isolation of the zones is achieved by placement of one or more memory based packers 10 .
[0026] Other types of telescoping perforation sections used in the apparatus of the present invention, along with the memory based packer, can have a sleeve which shifts between a fracturing position and an injection/production position, to convert the tool between these two types of operation. The sleeve can shift longitudinally or it can rotate.
[0027] In a first shifting-sleeve type, the sleeve can be a solid walled sleeve, as shown in FIGS. 9 and 10 , which shifts to selectively open and close the different telescoping elements, with some telescoping elements having a built-in sand control medium (which may be referred to in this case as “sand control elements”) and other telescoping elements having no built-in sand control medium (which may be referred to in this case as “fracturing elements”). In this embodiment of the apparatus 100 , the shifting sleeve 16 is a solid walled sleeve as before, but it can be positioned and adapted to shift in front of, as in FIG. 9 , or away from, as in FIG. 10 , one or more rows of fracturing elements 12 . It can be seen that the fracturing elements 12 have an open central bore for the passage of proppant laden fracturing fluid. The sand control elements 14 can have any type of built-in sand control medium therein, with examples of metallic beads and screen material being shown in the Figures. Whether or not the shifting sleeve 16 covers the sand control elements 14 when it uncovers the fracturing elements 12 is immaterial to the efficacy of the tool 100 . Isolation between the zones is provided by the expanded memory based packer 10 .
[0028] In a second shifting-sleeve type of the apparatus 100 , as shown in FIGS. 11 and 12 , the sleeve itself can be a sand control medium, such as a screen, which shifts to selectively convert the telescoping elements between the fracturing mode and the injection/production mode. In this embodiment, none of the telescoping elements would have a built-in sand control medium. This longitudinally sliding shifting sleeve 16 is constructed principally of a sand control medium such as a screen. FIG. 11 shows the sleeve 16 positioned in front of the telescoping elements 12 , for injection or production of fluid. FIG. 12 shows the sleeve 16 positioned away from the telescoping elements 12 , for pumping of proppant laden fluid into the formation. In this embodiment, none of the telescoping elements has a built-in sand control medium. Isolation between the zones is provided by the expanded memory based packer 10 .
[0029] In a third shifting-sleeve type, as shown in FIGS. 13 and 14 , the sleeve can have ports which are shifted to selectively open and close the different telescoping elements, with some telescoping elements having a built-in sand control medium (which may be referred to in this case as “sand control elements”) and other telescoping elements having no built-in sand control medium (which may be referred to in this case as “fracturing elements”). In this embodiment of the apparatus 100 , the sleeve shifts to selectively place the ports over either the “sand control elements” or the “fracturing elements”. This shifting sleeve 16 is a longitudinally shifting solid walled sleeve having a plurality of ports 24 . The sleeve 16 shifts longitudinally to position the ports 24 either in front of or away from the fracturing elements 12 . FIG. 13 shows the ports 24 of the sleeve 16 positioned away from the fracturing elements 12 , for injection or production of fluid through the sand control elements 14 . FIG. 14 shows the ports 24 of the sleeve 16 positioned in front of the fracturing elements 12 , for pumping of proppant laden fluid into the formation. In this embodiment, the fracturing elements 12 have an open central bore for the passage of proppant laden fracturing fluid. The sand control elements 14 can have any type of built-in sand control medium therein. Here again, whether or not the shifting sleeve 16 covers the sand control elements 14 when it uncovers the fracturing elements 12 is immaterial to the efficacy of the tool 10 . Isolation between the zones is provided by the expanded memory based packer 10 .
[0030] In a fourth shifting-sleeve type, as shown in FIGS. 15 and 16 , the sleeve can have ports, some of which contain a sand control medium (which may be referred to in this case as “sand control ports”) and some of which do not (which may be referred to in this case as “fracturing ports”). In this embodiment of the apparatus 100 , none of the telescoping elements would have a built-in sand control medium, and the sleeve shifts to selectively place either the “sand control ports” or the “fracturing ports” over the telescoping elements. This shifting sleeve 16 is a rotationally shifting solid walled sleeve having a plurality of ports 24 , 26 . A first plurality of the ports 26 (the sand control ports) have a sand control medium incorporated therein, while a second plurality of ports 24 (the fracturing ports) have no sand control medium therein. The sleeve 16 shifts rotationally to position either the fracturing ports 24 or the sand control ports 26 in front of the telescoping elements 12 . FIG. 15 shows the fracturing ports 24 of the sleeve 16 positioned in front of the elements 12 , for pumping of proppant laden fluid into the formation. FIG. 16 shows the sand control ports 26 of the sleeve 16 positioned in front of the telescoping elements 12 , for injection or production of fluid through the elements 12 . In this embodiment, all of the telescoping elements 12 have an open central bore; none of the telescoping elements has a built-in sand control medium. Isolation between the zones is provided by the expanded memory based packer 10 .
[0031] It should be understood that a rotationally shifting type of sleeve, as shown in FIGS. 15 and 16 , could be used with only open ports, as shown in FIGS. 13 and 14 , with both fracturing elements 12 and sand control elements 14 , without departing from the present invention. It should be further understood that a longitudinally shifting type of sleeve, as shown in FIGS. 13 and 14 , could be used with both open ports and sand control ports, as shown in FIGS. 15 and 16 , with only open telescoping elements 12 , without departing from the present invention.
[0032] While the particular invention as herein shown and disclosed in detail is fully capable of obtaining the objects and providing the advantages hereinbefore stated, it is to be understood that this disclosure is merely illustrative of the presently preferred embodiments of the invention and that no limitations are intended other than as described in the appended claims. | A method and apparatus for isolating formation zones preferably with a memory based material formed into an expansion element, with an outer diameter larger than a borehole, adjacent to a radially telescoping perforation element, converting the memory based expansion element to a stable, smaller, run-in diameter, running it into the borehole, then allowing the memory based material to expand and seal against the borehole wall. Expansion can be enhanced by expanding a mandrel on which the expansion element is formed. The expansion element separates two or more groups of outwardly radially telescoping perforation elements, to isolate formation zones and allow the perforation elements to access the isolated zones. | 4 |
BACKGROUND OF THE INVENTION
The present invention relates to a method for treating an exhaust gas, in particular a dioxin-containing exhaust gas emitted from a waste incinerator.
FIG. 1 is a diagram illustrating a typical method for removing particulate matter (e.g., flyash) from exhaust gas produced by a waste incinerator. Burning waste (e.g., municipal waste) in an incinerator creates byproducts of (i) ash and (ii) exhaust gas and flyash, the former residing in the incinerator itself and the latter passing through the stack of the incinerator. It is standard operating procedure to flow the exhaust gas and flyash through a boiler to quench the exhaust gas and reduce the temperature thereof to a sufficiently low level so that a bag filter can be used to remove the flyash from the exhaust gas. The resultant exhaust gas is then passed through a scrubber and emitted to the environment through a stack.
It is well known that the incineration of municipal waste materials creates large volumes of organic compounds and hydrocarbons. These materials serve as precursors for various compounds, some of which are highly toxic. For example, aromatic compounds such as phenol or benzene, or chlorinated aromatic compounds such as chlorophenol or chlorobenzene, react in the presence of flyash to form dioxin, which is highly toxic.
It is believed that formation of dioxin in the presence of flyash is the result of a catalytic reaction wherein flyash is the catalyst. It is also believed that the catalytic reaction occurs when the temperature of the exhaust gas drops below 400° C., which typically occurs at a location between the boiler and the bag filter.
While it would seem logical to simply remove the flyash from the exhaust gas before the temperature of the exhaust gas drops below 400° C., and thus prevent the formation of dioxin in the first instance, there is no industrially practical method or apparatus for accomplishing such a goal. Accordingly, the industry has adopted various methods by which dioxin is removed from incinerator exhaust gas prior to being emitted to the environment through the stack of the incinerator.
The use of sorbent materials is the most common method for removing dioxin from incinerator exhaust gas. Sorbents are materials that adsorb or absorb dioxin or dioxin precursors, and examples of such sorbents include certain cements (JP 97-2678543), activated carbon and activated white clay (JP 92-87624 A and JP 96-243341 A), activated coke (JP 97-29046 A), silicates (JP 97-75719 A and JP 97-75667 A), and zeolites (JP 97-248425 A).
While it is most common to add such sorbents to the exhaust gas at an exhaust gas temperature of less than 400° C., to thereby sorb dioxin per se, another known method (EP 0 764 457) discloses adding sorbents to the exhaust gas at an exhaust temperature of greater than 400° C. to remove dioxin precursors from the exhaust gas.
While all of the above-described methods are effective to remove dioxin from the exhaust gas to some degree, there are problems associated with each method. The main problem with using carbon-based sorbents is that there is a distinct possibility that the carbon will oxidize in the exhaust stream and cause a fire in the bag filter, for example. In addition to the obvious danger associated with such a fire, the heat generated as a result of the fire would cause all of the dioxin or dioxin precursors sorbed on the activated carbon to desorb and thus be emitted out of the incinerator stack.
The problem with using other sorbents such as silicates and zeolites, for example, is that the desorption temperature of those materials is too close to the vaporization temperature of dioxin itself. Specifically, the vaporization temperature of dioxin is about 220° C., whereas the temperature at which dioxin desorbs from materials such as silicates and zeolites ranges from about 220° C. to 260° C. Sorption of dioxin is most effective when the dioxin is in a gaseous state, and the sorption efficiency of a sorbent depends largely upon how close the dioxin desorption temperature of the material is to the vaporization temperature of dioxin. Accordingly, the sorption efficiency of materials such as silicates and zeolites is relatively poor, because the desorption temperature of those materials is too close to the vaporization temperature of dioxin.
One reason that activated carbon is effective as a dioxin sorbent is that its desorption temperature is not close to the vaporization temperature of dioxin. The problem of combustion in the bag filter, however, is still a significant concern.
It would be desirable to provide a method for removing dioxin from incinerator exhaust gases without the threat of fire (associated with the use of activated carbon) and without the problem of sorption inefficiency (associated with materials such as silicates and zeolites). To date, however, the industry has not provided any such method.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide a method for removing dioxin from an exhaust gas that overcomes the above-discussed problems associated with the prior art methods.
In accordance with one embodiment of the present invention, gamma-alumina is used as a sorbent to remove dioxin from an exhaust gas.
In accordance with another embodiment of the present invention, a method of removing dioxin from an exhaust gas includes the steps of introducing gamma-alumina into a stream of the dioxin-containing exhaust gas, and sorbing dioxin on the gamma-alumina. When used in particulate form, gamma alumina is introduced into the exhaust stream. Its method of operation is the same as activated carbon and granulation is helpful to the sorption process.
The inventors discovered that gamma-alumina sorbs dioxin like activated carbon, and, thus, can be used effectively as a sorbent of dioxin contained in an exhaust gas. Gamma-alumina has a dioxin desorption temperature of about 300° C., which is substantially higher than the vaporization temperature of dioxin (220° C.), and, thus, exhibits high dioxin sorptivity at temperatures not greater than 300° C. Additionally, gamma-alumina does not oxidize easily in the exhaust gas stream, and thus does not pose a significant threat of fire in the exhaust gas stream.
The gamma-alumina can be introduced into the exhaust gas stream as a sorption bed, such as a layer supported on a honeycomb structure substrate, or in particulate form. In the former case, the gamma-alumina can be introduced either upstream or downstream of the bag filter, provided the temperature of the exhaust gas upstream of the bag filter does not substantially exceed 300° C. In the latter case, the particulate gamma-alumina should be added upstream of the bag filter to allow collection of the gamma-alumina in the bag filter. The temperature of the exhaust gas upstream of the bag filter is not so critical in this case, as the particulate gamma-alumina continues to sorb dioxin as it flows downstream with the exhaust gas into the bag filter (where the temperature is certainly less than 300° C.). While it is possible to introduce the particulate gamma-alumina into the exhaust gas downstream of the bag filter, a second filter would be required to collect the particulate material.
BRIEF DESCRIPTION OF THE DRAWINGS
For a fuller understanding of the nature and objects of the invention, reference should be made to the following detailed description of a preferred mode of practicing the invention, read in connection with the accompanying drawings, in which:
FIG. 1 is a diagram illustrating a conventional waste incinerator system;
FIG. 2 is a diagram illustrating a waste incinerator system, wherein an integral body of gamma-alumina is introduced into the exhaust gas stream at position A or B;
FIG. 3 is a diagram illustrating a waste incinerator system, wherein particulate gamma-alumina is introduced into the exhaust gas stream upstream of the bag filter; and
FIG. 4 is a diagram illustrating a test apparatus used for demonstrating the efficacy of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
FIG. 2 is identical to the diagram shown in FIG. 1, but also includes boxes A and B to show the location of where a sorption bed of gamma-alumina would be introduced into the exhaust gas stream. The sorption bed of gamma-alumina could be introduced upstream or downstream of the bag filter, depending upon the temperature of the exhaust gas at those two locations. The preferred exhaust gas temperature range within which the exhaust gas should contact the sorption bed of gamma-alumina ranges from greater than 100° C. to no greater than 300° C., preferably greater than 220° C. to no greater than 300° C. If the sorption bed of gamma-alumina is contacted with the exhaust gas at a temperature of less than 100 ° C., water vapor in the exhaust gas significantly deteriorates the sorption efficiency of the gamma-alumina. On the other hand, if the sorption bed of gamma-alumina is contacted with the exhaust gas at a temperature greater than 300° C., the gamma-alumina is substantially incapable of sorbing dioxin contained in the exhaust gas.
While the sorption bed of gamma-alumina can take any form, it is preferred to be introduced into the exhaust gas stream in the form of porous pellets or a high surface area honeycomb structure, such as those structures typically used in treating automobile exhaust gas. In both cases, a gamma-alumina slurry is prepared, applied to the porous pellets or substrate as a washcoat, and, then dried to form a solid layer.
When using a honeycomb structure as the underlying substrate, it is most preferred that the honeycomb structure be formed of a low thermal expansion coefficient ceramic material, such as cordierite or an equivalent material, with a layer of gamma-alumina formed on the exposed surfaces of the underlying ceramic substrate.
While the thickness of the gamma-alumina layer formed on the substrate is not critical it should range from 10 μm to 1 mm, preferably 100 μm to 500 μm. While the dimensions of the honeycomb body will vary depending upon application, the active surface area of the gamma-alumina should be at least 3 m 2 per unit volume (NM 3 ) of exhaust gas to be treated.
After the dioxin has been sorbed by the gamma-alumina carried on the honeycomb substrate, the substrate is heated to a temperature exceeding 500° C. to desorb the dioxin from the gamma-alumina and thermally decompose the dioxin into non-toxic byproducts, which can then be emitted into the environment through the incinerator stack.
FIG. 3 is also identical to FIG. 1, but shows the location where gamma-alumina in particulate form would be introduced into the exhaust gas stream, in the same manner as activated carbon in the prior art. It is preferable to granulate the gamma-alumina to improve handling and the flow properties of the powder. It is also preferable to introduce the gamma-alumina at this location so as to make use of the collection function of the bag filter that is typically standard equipment in municipal incinerator systems. It is possible to introduce the particulate gamma-alumina downstream of the bag filter, but such an operation would require a secondary filter to collect the particulate gamma-alumina.
While any type of particulate gamma-alumina could be used, it is preferred that the particles have an average particle diameter (φ ave ) ranging from 1 to 100 μm.
The volume of particulate gamma-alumina introduced into the exhaust gas stream will depend upon the volume of exhaust gas to be treated. Generally speaking, a sufficient amount of particulate gamma-alumina should be added to provide 3 m 2 surface area of gamma-alumina for every 1 Nm 3 of exhaust gas to be treated.
Once the dioxin is sorbed on the particulate gamma-alumina, that material is collected in the bag filter along with the flyash, and disposed of in a manner well known in the art.
It is also possible to introduce hydroxides, precursors of gamma-alumina, into the exhaust gas stream to sorb dioxin. Such hydroxides are heated in the exhaust gas stream, dehydrated and converted to gamma-alumina, which in turn sorbs dioxins in the gas stream.
EXAMPLE
The following example is provided to illustrate the inventive concepts of the present invention, and is not intended to in any way limit the present invention in scope or spirit.
A test apparatus as shown in FIG. 4 was constructed. The apparatus included a 22 mm diameter tube designed to hold powder materials in the regions marked “tube A” and “tube B”. Each of these regions was also exposed to a dedicated heat source to control the temperature of the respective region.
Y-zeolite powder was added to tube B and held there in the form of a sorption bed. A solution containing 0.01 mL of DMF (Dimethyleformamid) of dibenzo-p-dioxin (50 mg/mL) was doped into tube B. Various other materials were held in tube A each also in the form of a sorption bed. Each material was added to tube A in an amount of 50 grams. A supply of He was connected to the upstream side of tube B and a gas chromatograph (GC.) was connected to the downstream side of tube A to detect the presence of dioxin in the gas stream passing through tube A.
Tube A was heated to 275° C., 300° C. and 325° C., He was supplied to the tube at 500 mL/min, and tube B was heated to 275° C. (to desorb the dioxin from the Y-zeolite). These steps were repeated for each material added to tube B. The detection of dioxin by the GC is shown in the following Table:
Sorbent in tube A
275° C.
300° C.
325° C.
activated carbon
none
none
none
gamma alumina
none
none
none
bentonite
none
detected
detected
Y-zeolite
detected
detected
detected
laponite
detected
detected
detected
clinoptilolite
detected
detected
detected
This experiment confirmed that gamma-alumina is as effective as activated carbon in sorbing dioxin, but without the inherent drawbacks associated with activated carbon.
While the present invention has been particularly shown and described with reference to the preferred mode as illustrated in the drawing, it will be understood by one skilled in the art that various changes in detail may be effected therein without departing from the spirit and scope of the invention as defined by the claims. | A method of removing dioxins from an exhaust gas, including the steps of introducing gamma-alumina into a stream of the dioxin-containing exhaust gas, and sorbing dioxins on the gamma-alumina. | 5 |
FIELD OF THE INVENTION
This invention relates to a sleeve that is designed to receive a mobile electronic device and to enable such a device to be charged by means of an inductive charging system.
BACKGROUND TO THE INVENTION
Mobile electronic devices, including mobile phones, portable music and video players, digital cameras, camcorders, computer peripherals etc. are widely used today. For environmental reasons, such devices are often powered by rechargeable batteries.
There exist a number of methods for charging the rechargeable batteries. As shown in FIG. 1 , a first method is to connect the electronic devices 1 to a conventional power line through a power adaptor 2 . This method also includes the possibility of removing batteries out of the device and charging them with external chargers, or charging a battery through a USB connection 3 on a PC. No matter what kind of approach is used, the power adaptors and their cables are always cumbersome, and in the case of charging using a USB port, this is restricted by the availability of computers that can be found. Furthermore, the USB port normally can only output a power of 2.5 W which is sometimes lower than the power requirement for recharging and which can cause the charging speed to be slower than a normal battery charger, though it does have the advantage of simultaneous data exchange with the computer at the same time as battery charging.
FIG. 2 shows the pin definition of the connecting port 4 of an exemplary mobile electronic device and its corresponding power/data connector 9 . For simultaneous power and data transfer, there are two pins (pin 2 and pin 3 ) for data connection in addition to the pins (pin 1 and pin 4 ) used for charging. Many devices have their own charging protocol which needs some predefined voltage level at the data pins to start or continue on charging. For example, some devices need pin 2 and pin 3 to have voltage of 3 V and 2 V, respectively, so that the charging process can be maintained. This requirement can be easily met if the device is charged through a USB port because the data pins can be controlled by the computer. However, when such a device is charged by using a power adaptor 2 , a voltage divider as shown in FIG. 2 must be used to provide the required voltage level for data pins.
To get rid of the power wire or the USB connector one possible solution is to use an inductive battery charging platform examples of which are disclosed in U.S. Pat. No. 7,164,255B and US20070029965A. As shown in FIG. 3 , the mobile electronic device is inductively coupled with a charging platform 5 which eliminates the need for charging cables to the device. The charging platform 5 is provided with one or more primary windings that generate a magnetic flux that can be picked up by a secondary winding 6 which may be provided integrally with the electronic device. For example, the electronic device may be provided with an inductive energy receiving unit (IERU) 7 which includes the secondary winding 6 and the associated processing circuitry 8 as shown in FIG. 4 .
As shown in FIG. 4 , an energy receiving winding or coil 6 receives magnetic flux from the charging platform, and the received AC energy is rectified and regulated to a suitable DC voltage to charge the battery. In the prior art it is known that the IERU 7 may be integrated into the device or into the battery pack (US20070029965A) and this is the best approach for future devices. Also known is that the IERU 7 may be integrated into a new back cover for a device which may be used to replace the original (US20060061326A, US20060205381A).
However, there is a need to enable existing devices that are not provided with such an integral IERU—or devices where it is difficult to provide an integrated IERU—to be charged using such an inductive charging platform. One solution to this is to provide the IERU in an external module which is attachable to the back of the device (GB2399466B, US20060205381A). The output of IERU is connected to the connecting port of the device through a short wire or through a power connector. This is a straightforward approach to adapt conventional devices to the charging platform. However, the added module is an extra ‘burden’ to the devices, which has no other function or attraction to a consumer.
SUMMARY OF THE INVENTION
According to the present invention there is provided a sleeve for receiving a mobile electronic device, the sleeve including a winding for receiving magnetic flux from an inductive charging system, an energy processing circuit for generating a DC output voltage from the magnetic flux, and electrical connection means for connecting the circuit to a device received within the sleeve whereby the device may be charged by placing the sleeve with the device therein on a surface of an inductive charging system.
Preferably the sleeve comprises at least one planar surface and the winding is a planar winding integrally formed with the surface. Electromagnetic shielding may be provided between the winding and a side of the surface facing a device when received in the sleeve.
Preferably the planar winding is formed on a printed circuit board, and the energy processing circuit may be formed on the same printed circuit board as the planar winding. Alternatively, the energy processing circuit and the electrical connection means are formed on one printed circuit board.
The connection means is preferably a combined power and data connector adapted to be received within a combined power and data socket formed in a device.
In one embodiment of the invention the sleeve is provided with an attachment clip and the winding is provided as part of the clip. The clip may further comprise electromagnetic shielding on a side of the clip that in use will face a device received within said sleeve.
The energy processing circuit may preferably include a diode provided at the output of the circuit to prevent reverse current flow. The sleeve may also be provided with a port for connecting a device received therein to an external power source such as a computer or a power adaptor.
Preferably means are provided for disabling either the energy processing circuit or the external power source when both are provided. When the energy processing circuit is disabled, preferably the inductive charging system may also be disabled. Preferably the energy processing circuit is provided with means for clamping data pins of said device at predetermined voltages and said clamping means is disabled when said external power source is provided.
BRIEF DESCRIPTION OF THE DRAWINGS
Some embodiments of the invention will now be described by way of example and with reference to the accompanying drawings, in which:
FIG. 1 illustrates schematically prior art methods for charging mobile electronic devices,
FIG. 2 illustrates a typical configuration of data and charging pins for a device to be charged via a USB port or a power adaptor,
FIG. 3 illustrates an inductive battery charging platform according to an example of the prior art,
FIG. 4 illustrates an inductive energy receiving unit for use in the prior art,
FIG. 5 illustrates schematically a first embodiment of the invention,
FIG. 6 is a view of a sleeve for use in an embodiment of the invention,
FIGS. 7( a ) and ( b ) are cross-sectional views of the sleeve of FIG. 6 ,
FIG. 8 is a back view of the sleeve in an alternative embodiment,
FIG. 9 shows schematically the electrical connection between the sleeve and an electronic device,
FIG. 10 shows a sleeve according to a further embodiment of the invention, and
FIG. 11 shows schematically an alternative electrical connection between the sleeve and an electronic device.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
As will be seen from the following description, in preferred embodiments of the present invention the inductive energy receiving unit (IERU) is integrated with a sleeve that is designed to receive at least a part of an electronic device. The sleeve provides the benefits of (a) receiving inductive energy (b) protecting the mobile device, and (c) also the sleeve can be provided with a decorative pattern, or advertising or promotional material. It will be understood in this regard that the term “sleeve” is intended to cover any article that is designed to hold a mobile electronic device.
FIG. 5 shows a first embodiment of the invention. This embodiment includes a sleeve 10 that is of such a size that it can receive a mobile electronic device 20 . The sleeve can be made of silicone, leather, vinyl, plastic, fabric, or any other material suitable to make a sleeve for mobile electronic device protection. It will be understood that the dimensions of the sleeve will be chosen depending on the size and shape of a mobile electronic device that it is intended to receive. A range of differently sized sleeves may be provided. The sleeve should be sized such that it is sufficiently large to permit the electronic device to be inserted into and removed from the sleeve though an opening 11 provided at one end of the sleeve, while being a sufficiently tight fit that the device is held securely. The sleeve may be formed of any suitable material which may include a resilient material chosen to assist the holding of the device by the sleeve.
The sleeve 10 may also be provided with one or more further openings 12 to allow a user to access the device 20 when it is received therein including accessing any control buttons, touch screen or the like, or to enable any camera, microphone or the like that forms part of the device to function properly. The sleeve is formed integrally with the IERU such that the sleeve may receive energy inductively when it is placed on or in proximity with the charging platform 30 . For example, one or more secondary windings may be formed in the back face 13 of the sleeve with the associated power electronics being provided at a suitable location as will be described further below.
As can be seen from FIG. 6 , which is a top view of the sleeve, at the end of the sleeve remote from the opening 11 through which the device is inserted into the sleeve, there is provided a power/data connector 14 . When the mobile electronic device is inserted into the sleeve 10 , the power/data connector 14 engages the connecting port 4 of the mobile electronic device. FIG. 6 also shows the associated energy processing circuitry 15 . Processing circuitry 15 may comprise a printed circuit board 17 (PCB) with electronic components mounted on it including the rectifier and regulator as shown in FIG. 4 . The rectifier rectifies the received high frequency AC signal to DC and may take any suitable form including a full-bridge rectifier, voltage doubler, current doubler, center-tap rectifier or forward rectifier. In the embodiment shown in FIG. 6 the processing circuitry 15 is adjacent the power/data connector 14 but it will be understood that this is not essential.
Detailed examples of two possible structures for the sleeve in particular with regard to the location of the processing circuitry 15 are shown in FIGS. 7( a ) and ( b ) which are cross-sectional views of the sleeve 10 together with a mobile electronic device 20 inserted inside. For simplicity, only a part of the back face 13 of the sleeve 10 is shown. In this context it should be noted that the term ‘back’ means the side intended to face the inductive battery charging platform in a charging operation.
In the embodiment of FIG. 7( a ) the energy processing circuitry 15 is placed beside the power/data connector 14 . The energy processing circuitry 15 and the power/data connector 14 may, but not are limited thereto, share the same PCB 17 . The input of the energy processing circuitry is the received AC energy from a secondary energy receiving winding layer 31 , while its output is a DC supply that is connected to the connector 14 which is inserted in the connecting port 4 of the device 20 . One important design issue of this structure is to make the back wall of the sleeve as thin as possible. To achieve this goal, the thickness of the winding layer 31 as well as the shielding layer 32 must be minimized. The energy receiving winding layer 31 may take the form of one or more conductive windings formed on a PCB which may have a thickness of only a few hundred microns. The other structures for the winding layer 31 are possible however and may include one or more windings in the form of a planar spiral coil. The shielding layer 32 is important as it is designed to prevent magnetic flux leakage into the device and which may detrimentally influence the operation of the device. The shielding layer 32 may be a double-layer shielding structure which contains a layer of soft-magnetic material and a layer of conductive material as described in U.S. Pat. No. 6,501,364B and U.S. Pat. No. 6,888,438B. Such a structure can have a thickness of only a few hundred microns and can still provide acceptable shielding effectiveness.
Another possible structure is shown in FIG. 7( b ) in which the energy processing circuitry 15 is placed beside the winding and shielding layers 31 , 32 , instead of the connector 14 . This embodiment has the advantage of reducing the minimum length of the sleeve, compared to FIG. 7( a ). However, this approach can only be implemented if the height of the components in the energy processing circuitry is low enough. In this embodiment, the energy processing circuitry 15 and the winding layer 31 may, but are not limited thereto, share the same PCB.
Another embodiment is shown in FIG. 8 which is a back view of a sleeve 10 . The sleeve 10 is provided with a clip 16 at the back which may be used for attaching the sleeve to a bag or a belt or the like. As shown in FIG. 8 , the winding and shielding layers 31 , 32 can be formed as part of the clip 16 . The only limitation is the size of the belt clip which must be large enough to contain the winding and shielding layers 31 , 32 .
In all the above embodiments, the power/data connector 14 is always connected with the connecting port 4 when the device 20 is inserted in the sleeve 10 . To avoid energy leakage from the device (battery) to the energy processing circuitry 15 , especially when the device is not being charged, a diode (D 0 in FIG. 9 ) is added at the output of the energy processing circuitry 15 to prevent any reverse current. In addition, in FIG. 9 , R 1 -R 4 are four resistors that provide required voltage levels to the data pins of the power/data connector 14 as discussed above with reference to FIG. 2 . If other charging protocols are required by the data pins, a corresponding method for providing controlled voltages to the data pins can be provided.
It will be understood that in the above embodiments when a device 20 is put into the sleeve 10 , the connecting port 4 of the device is occupied by the power/data connector 14 of the sleeve 10 . It would therefore not be possible to connect the device 20 to a computer (or to a dock) through a USB connector for data transfer while the device is in the sleeve 10 as there would be no usable port. A straightforward solution for all the above embodiments is to take the device 20 out of the sleeve and connect it through a USB cable to a USB port in a computer in a conventional manner. However this is cumbersome for many users and frequent plug and unplug of the connectors in the sleeve may shorten its life.
A better solution is shown in the embodiment of FIG. 10 . Compared to FIG. 5-FIG . 8 , the sleeve in FIG. 10 further has an external port 21 through which the device can be connected to a computer (or another external charger if needed). The external port 21 can be a part of the energy processing circuitry 15 or may be placed anywhere on the sleeve. With this external port 21 , a user can place the sleeve 10 (including the device 20 ) on an inductive charging platform for charging or connect the device 20 to a computer without taking the device 20 out of the sleeve 10 .
However, if a user were to simultaneously place the sleeve 10 (including device 20 ) on the charging platform and connect it to a computer, problems may arise. Firstly, the received energy from the IERU may destroy the USB port of a computer. Secondly, the voltage level of the data pins (pin 2 and pin 3 in FIG. 9 ) are clamped at 3 V and 2 V, respectively, so that data transfer is disabled. To solve these potential problems, the energy from one input (IERU or external port) must be disabled. A possible embodiment of a circuit to implement this idea is shown in FIG. 11 . In FIG. 11 , a switch, S 1 is an added switch to select the energy input from the energy processing circuitry 15 or from the external port 21 . S 1 is normally at the position of ‘c’, when no energy is input. When the DC output of energy processing circuitry 15 is high, S 1 is controlled to be at the position of ‘a’. The device is solely powered by IERU. When pin 1 of the external port 21 is high, (which means that it has been connected to a computer) S 1 is controlled to be at the position of ‘b; and the device is solely powered by the external port. Pin 1 at high also has the function to turn off S 2 which is another added switch. When the device is connected to a computer, data pins (pin 2 and pin 3 ) are solely controlled by the computer so that data transfer is enabled. D 1 and D 2 are two diodes added to avoid the voltage at the data pins from going back into the R 1 -R 4 circuit.
In a possible situation that the DC output of energy processing circuitry 15 and pin 1 of external port 21 are both high, the following possibilities exist:
1) Position ‘a’ of switch S 1 has higher priority. No matter whether the device is connected to a computer or not, it is always powered by the inductive charging platform. This approach has the advantage of simultaneously charging with higher power (than 2.5 W of USB) and data transfer (because S 2 has been turned off). 2) Position of ‘b’ of switch S 1 has higher priority. No matter whether the device is placed on an inductive charging platform or not, it is always powered by the external port. Furthermore, (not shown in FIG. 11 ), under this condition, the status of pin 1 of the external port can be fed into a MCU (Micro Controller Unit) of the energy processing circuitry 15 . If pin 1 of the external port is high, the MCU may also send information back to the charging platform through a suitable communication method to stop the power transfer at all, which further saves energy.
The above two possibilities can be chosen based on the requirement of customers. | There is disclosed a sleeve for holding a portable electronic device such as an MP3 player, mobile telephone, PDA and the like. The sleeve is provided with an integrally formed secondary winding that enables the sleeve to pick up magnetic flux from an inductive charging platform and associated circuitry for generating a DC charging voltage that can be used to charge a battery in the device while the device is received within the sleeve. The sleeve is formed with a connector designed to fit a power/data connection socket in the device, and may also be provided with a connection port enabling the device to be connected to a computer while it is received within the sleeve. | 7 |
CROSS REFERENCE TO RELATED APPLICATION
This application claims the benefit of U.S. Provisional Patent Application Ser. No. 61/441,504, filed Feb. 10, 2011, which is herein incorporated by reference in its entirety.
BACKGROUND
A staircase is typically one of the first parts of a building to be constructed. After the stairs are constructed, they are often used by construction workers while the remainder of the building is constructed and finished. This period of time after the stairs are constructed and before the building is finished can expose stairs, and particularly front nosings of the stairs, to significant damage, wear, contamination, etc. For example, the exposed features of the stair nosings can be scratched, dented or splashed with paint or other material while the building is being finished.
To protect the stair nosings after they are constructed, construction works often place a layer of tape over the upper surfaces of the nosings and then remove the tape after construction of the building is complete.
SUMMARY
Embodiments of stair nosing assemblies are disclosed herein that come pre-assembled with a protective cover layer that can remain covering the nosing after construction of the stairs while the remainder of the building is constructed and finished. The cover can then be quickly, easily, and accurately removed by lifting a front lip and thereby breaking the front and upper portions of the cover apart from an embedded rear lip.
One exemplary stair nosing assembly can comprise an elongated polymeric base, an elongated metal plate adhered to the base, and an elongated polymeric cover temporarily covering the base and the plate. The base can comprise at least one anchor portion extending downwardly from the upper portion for attaching the assembly to a rearward projecting lip of a tread pan and/or for embedding in a concrete tread. The plate can have various features to enhance traction and visibility. The cover can comprise front and rear lips that engage with front and rear edges of the base to temporarily secure the cover over upper surfaces of the base and the plate. The cover can further comprise a horizontally extending weakened region adjacent to or in the rear lip. When lower portions of the assembly are embedded in a concrete tread, the cover is configured to fracture along the weakened region when the front lip of the cover is lifted upward from the base, leaving the rear lip of the cover remaining embedded in the concrete and allowing the rest of the cover to be removed to expose upper surfaces of the base and plate.
The foregoing and other objects, features, and advantages of the disclosure will become more apparent from the following detailed description, which proceeds with reference to the accompanying figures.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an exploded cross-sectional end view of an exemplary stair nosing assembly, shown in the context of other portions of a stair.
FIG. 2 is a perspective view of the assembly of FIG. 1 , with various components of the assembly cut away at different lengths for illustrative purposes.
FIG. 3 is a cross-sectional perspective view of another exemplary stair nosing assembly shown coupled to a metal tread pan, with various components of the assembly cut away at different lengths for illustrative purposes.
FIG. 4 is a cross-sectional perspective view of a finished concrete and metal stair with the stair nosing assembly of FIGS. 1 and 2 installed, after a cover layer has been removed.
FIG. 5 is a cross-sectional end view of a finished concrete stair with an alternative embodiment of the nosing assembly installed, prior to the cover layer being removed.
DETAILED DESCRIPTION
Described herein are embodiments of a nosing assembly, components thereof, and methods related thereto. The following description is exemplary in nature and is not intended to limit the scope, applicability, or configuration of the invention in any way. Various changes to the described embodiment may be made in the function and arrangement of the elements described herein without departing from the scope of the invention.
The nosing assembly and components described herein are primarily intended for use with stair construction, but can also be used to form a nosing for other similar structures or objects, such as curbs, sidewalks, ledges, edges, and the like. Thus, although this disclosure proceeds with reference mainly to stairs, one of ordinary skill will understand that the inventive features disclosed herein can similarly be applied to these analogous fields of endeavor.
As shown in FIGS. 1 and 2 , a nosing assembly 10 can comprise a plurality of components. These components can include a base 12 , a plate 14 , an adhesive 16 , a cover 18 , and/or other optional components. The nosing assembly can be pre-assembled and installed as a unit during the construction of a stair or a stair case. The base 12 can couple the nosing assembly 10 to a stair. The adhesive 16 can couple the plate 14 to the base 12 . The cover 18 can cover and protect the base 12 and plate 14 from damage and/or contamination, such as during transportation and construction, and can be removed to expose the base 12 and plate 14 (see FIG. 4 ), such as after construction of the stair case is complete.
The nosing assembly 10 can be elongated and have a generally constant cross-section transverse to the elongated direction, or length. The length of the nosing assembly 10 can be selected to correspond to the width of the stair on which it is installed. The base 12 , plate 14 , adhesive 16 and cover 18 can each have the same or similar length. The nosing assembly 10 can be any width (measured from the front edge to the rear edge), and in some embodiments is approximately two inches wide.
The base, or tread portion, 12 can be comprised of a durable polymeric material, such as PVC. As shown in FIG. 1 , the base 12 can comprise a tread portion 20 that forms a generally horizontal upper portion 22 and curves downwardly at a front side to form a generally vertical front lip 24 . The tread portion 20 can further comprise a recessed area between a front rib 28 and a rear rib 26 . This recessed area can be sized and shaped to receive the adhesive 16 and the plate 14 between the ribs 26 and 28 .
The rear of the upper portion 22 can terminate in a rear edge 30 and the bottom of the front lip 24 can terminate in a bottom edge 32 . The rear edge 30 and bottom edge 32 can engage with the cover 18 , as described below.
The base 12 can comprise a downwardly projecting rear flange 34 extending from the rear of the upper portion 22 . The rear flange 34 can comprise a rearwardly opening recess, or cavity, 35 adjacent the upper portion 22 and an expanded bottom end portion 38 . The cavity 35 can extend horizontally along the base and can be configured to receive another component in a snap-fit connection. The cavity 35 can alternatively be filled with concrete during installation and help retain the nosing 10 to the step.
The base 12 can further comprise a downwardly projecting anchor portion 36 extending from the lower surface of the upper portion 22 between the rear flange 34 and the front lip 24 . The anchor portion 36 of the base 12 can comprise a forwardly extending lip 40 and/or a downwardly extending flange 42 that terminates in an expanded bottom end portion 44 . The lip 40 can be used to couple the base 12 to a rearwardly projecting lip of a tread pan, as shown in FIG. 4 , or to an anchor 80 mounted in the concrete, as shown in FIG. 5 .
The plate 14 can be comprised of durable material, such as a suitable metal (e.g., aluminum or steel) and/or polymeric material. The plate 14 can comprise a variety of upper surface features designed to provide foot traction, illumination, aesthetic appearance, and/or other functions. For example, the plate 14 can comprise one or more ribs 50 extending lengthwise of the plate, as shown in FIGS. 1-4 . The plate 14 can further comprise a friction-enhancing material and/or a textured pattern 52 on the upper surface, such as knurling, to provide grip and/or an aesthetic appearance. One or more surfaces of the plate 14 can further comprise a photoluminescent, or “glow-in-the-dark,” material, such as the photoluminescent strips 54 shown in FIGS. 1 and 4 . One or more surfaces of the plate 14 can also comprise a friction-enhancing material, such as the strips 56 shown in FIGS. 1 and 4 . The photoluminescent material and/or the friction-enhancing material can comprise strips of material inserted into mating receptacles in the plate 14 between the ribs 50 . These materials can comprise a spray-on substance, adhesive strips, or other materials coupled to the plate. In addition, various surfaces of the plate 14 can be coated or painted to provide desirable properties, such as aesthetic appearance.
On some exemplary embodiments, the upper and/or lower surfaces of the plate 14 are painted, such as black or yellow. Yellow paint, for example, can provide a visual alert and/or contrast with other materials to signify the edge of a step. In one example, an aluminum plate is first painted black, and then portions of the black paint are removed, such as the top edges of the ribs 50 and/or the front and rear edges of the plate, to expose the shiny, silvery color of the metal, creating a contrasting silver and black contrast. In this example, the black can be replaced with any other color, such as yellow, to provide a similar effect.
The plate 14 can be coupled to the base 12 using an adhesive 16 , such as a double-sided tape, a layer of adhesive applied in fluid form, or the like. The adhesive 16 can be releasable in order to allow removal and replacement of the plate 14 , such as if the plate is worn or damaged or if a plate with different surface features is desired. To remove and replace the plate 14 , the plate can simply be peeled off, the adhesive 16 can be removed, and a plate can be attached with a new adhesive.
The cover 18 can be comprised of a flexible, durable material, such as PVC or other polymeric material. The cover 18 can comprise an elongated sheet of material having curled or hooked front 62 and rear 60 portions that engage with the front edge 32 and rear edge 30 , respectively, of the base 12 to hold the cover 18 in place over the base 12 and plate 14 , as shown in FIGS. 3 and 5 .
As shown in FIGS. 1 and 5 , the cover 18 can comprise a horizontal nick, or weakened region, 64 adjacent to the rear portion 60 that extends lengthwise of the cover 18 and allows the cover to easily fracture along the nick 64 to facilitate removal of the exposed portion of the cover 18 from the nosing assembly 10 . The nick 64 can comprise one or more slots, grooves, perforations, apertures, weakened regions, and/or other structural features that facilitate the separation of the rear portion 60 from the remainder of the cover when the cover is lifted upwardly from the stair. The structural features that comprise the nick 64 can be located at one or both of the inner and outer, or forward-facing and rear-facing, surfaces of the cover between the rear portion 60 and the remainder of the cover. The nick 64 can furthermore be pre-stressed or pre-weakened prior to assembly with the base 12 to further facilitate fracturing.
The nosing assembly 10 can be installed on different types of stair frames. As a first example, the nosing assembly 10 can be installed on a stair frame as shown in FIGS. 3 and 4 . This exemplary stair system can comprise a generally vertical metal plate 100 and a generally horizontal metal plate 102 . The front plate 100 can have a rearwardly extending, horizontally disposed upper lip 104 that engages with the lip 40 of the base 12 . The lip 104 can extend into a gap formed between the upper surface of the lip 40 and the lower surface of the upper portion 20 . The lip 40 can resiliently flex to expand the gap and receive the metal lip 104 in the gap. The upper surface of the lip 104 can contact the upper portion 20 while the front lip 24 of the base 12 can contact the front surface of the plate 100 to hold the nosing assembly 10 on the metal stair frame. The anchor portion 36 and rear flange 34 of the base can hang freely behind the lip 104 . Concrete can then be poured into the pan formed by the plates 100 , 102 . The concrete can fill the pan up to the level of the top surface of the cover 18 , or slightly lower, such as up to the level of the upper surface of the plate 16 . The rear portion 60 of the cover can be submerged in the concrete and pinned between the rear edge 30 of the base 12 and the concrete. The anchor portion 36 and the rear flange 34 of the base can also be submerged in the concrete. The expanded lower end portions 38 and 44 and the cavity 35 assist in physically retaining the base 12 in the concrete.
After the concrete cures (see FIG. 4 ) and/or after construction of the stair case is complete, the cover 18 can be removed. The front portion 62 of the cover can be pulled forwardly away from the lower edge 32 of the front lip 24 of the base 12 to free the front of the cover 18 from the stair. The front portion 62 can then be lifted upwardly until the rear portion 60 of the cover 18 fractures apart from the rest of the cover at the nick 64 . As the majority of the cover 18 is separated from the stair, the rear portion 60 of the cover can remain buried in the concrete beneath and behind the rear edge 30 of the base 12 . The nick 64 can be positioned in the cover 18 such that the rear portion 60 of the cover that remains in the concrete can have an upper surface that is flush with the level of the concrete and/or the rear edge 30 of the base 12 .
In other embodiments, such as shown in FIG. 5 , the nosing assembly 10 can be installed with a stair system that lacks a vertical plate and rearwardly projecting metal lip for the nosing assembly for attachment. In one such stair system, a temporary mold, or framework can be constructed and concrete can be poured into the mold to form the stair tread. As the concrete cures, the nosing assembly 10 can be pressed into the concrete such that the front lip 24 rests against the front of the concrete stair and the upper surface of the cover 18 is flush with or slightly above the level of the concrete. The anchor portion 36 and the rear flange 34 of the base 12 can be submerged in the concrete such that the expanded portions 44 , 38 fix the base 12 in the concrete. After curing, the framework can be removed, leaving the nosing assembly 10 at the upper front edge of the concrete tread. After construction, the cover 18 can be removed, as described above, exposing the front and upper portions of the base 12 and the plate 14 .
In some embodiments of the nosing assembly 10 , the anchor portion 36 of the base 12 can comprise a hooked lip portion 40 without a downwardly projecting flange 42 , as shown in FIGS. 3 and 5 , for examples. The downwardly projecting flange 42 may not be needed to secure the base 12 to the concrete, such as when the lip portion 40 is clipped onto a rearwardly extending lip 104 of the stair frame, as in FIG. 3 .
In an alternative embodiment, an additional component can be included in the nosing assembly 10 , as shown in FIG. 5 , that engages the lip portion 40 and provides a downwardly projecting flange for embedding in the concrete. For example, an adapter, or anchor, 80 (see FIG. 5 ) can be provided that comprises an upper lip 82 that engages with the lip 40 of the base 12 . The adapter 80 can further comprise a downwardly extending flange portion 84 terminating in an expanded lower edge 86 that serves the same purpose as the lower edge 44 shown in FIG. 1 . The adapter 80 can have a cross-sectional shape generally in the form of a question mark, as shown in FIG. 5 . The adapter 80 can comprise a single elongated strip or it can comprise a plurality of separate pieces that can be spaced apart along the length of the base 12 . The adapter 80 can be used, for example, to convert a base 12 that was designed to be used with a stair frame having metal lip 104 that engages the lip 40 , as in FIG. 3 , to be used with a stair frame that does not have such a lip.
In other embodiments, an additional component can be added to the rear of the base 12 , such as adapter 90 shown in FIG. 5 . The adapter 90 can have an upper rib 92 that engages, such as with a snap or friction fit, within the cavity 35 at the rear of the base 12 . The adapter 90 can extend below the level of the rear flange 34 and can comprise an expanded lower edge 94 . The adapter 90 can, in effect, extend the height of the rear flange 34 as desired. In some embodiments, (not shown) the lower edge 94 can contact a lower surface of the concrete stair, such as the bottom of a metal tread pan, to create a rear support for the nosing. This feature can help keep the upper surface of the nosing level and at a desired height relative to the concrete. The adapter 90 can comprise a single elongated strip or can comprise a plurality of separate pieces that can be spaced apart along the length of the base 12 . In some embodiments, both adapters 80 and 90 can be used.
One benefit of the nosing assemblies 10 described herein is that the cover 18 can protect the exposed surfaces of the base 12 and plate 14 during the installation of the stair and for an additional period of time after installation is complete, until the cover is removed. For example, after the installation of the nosing on a stair, the stair may be used by construction workers while the remainder of the building is constructed and finished. This period of time after the stairs are constructed and before the building is finished can expose the base 12 and plate 14 to significant damage, wear, contamination, etc. For example, the upper features of the plate can be scratched, dented or splashed with paint or other material while the building is being finished. The cover 18 can prevent and/or reduce these undesirable and unnecessary exposures. When the building is complete and ready for normal use, the covers 18 can be removed leaving a pristine nosing. The removable cover 18 described herein can obviate the alternative use of duct tape covering or other ad hoc protective devices used by construction workers to cover the stair nosing. These ad hoc attempts to protect the nosing can furthermore be less effective, less accurate, more time consuming and/or more expensive that using the nosing assemblies described herein. The cover 18 can be very tough and durable, can precisely cover the areas of the nosing that need to be protected, can come pre-installed with the rest of the nosing, and can be removed in one quick motion without leaving any residue or markings behind. The cover 18 can furthermore comprise upper surface features that provide functional benefits, such as traction and illumination, to the construction workers prior to removal.
The nosing assembly 10 can be pre-assembled with the base 12 , plate 14 and cover 18 engaged together. The adapter 80 and/or the adapter 90 can also be pre-engaged with the bottom of the base 12 . Thus, the installer merely needs to remove the nosing assembly 10 from its packaging and either clip it onto a flange of a stair frame, as shown in FIG. 3 , or press the nosing assembly into wet concrete. After the concrete cures, the installer simply lifts and breaks the cover off and the stair nosing is ready for use. Later, if desirable, the plate 14 can be peeled off and replaced with another plate without removing or damaging any other portion of the nosing other than the adhesive 16 .
In some embodiments, the base 12 and/or the cover 18 can be made of a material that is photoluminescent and/or emits light in the dark. Portions of the base 12 can be exposed below and behind the plate 14 , such that the nosing can be easily recognized by a person moving up or down the stairs.
As used herein, the terms “a”, “an” and “at least one” encompass one or more of the specified element. That is, if two of a particular element are present, one of these elements is also present and thus “an” element is present. The terms “a plurality of” and “plural” mean two or more of the specified element. As used herein, the term “and/or” used between the last two of a list of elements means any one or more of the listed elements. For example, the phrase “A, B, and/or C” means “A,” “B,” “C,” “A and B,” “A and C,” “B and C” or “A, B and C.” As used herein, the term “coupled” generally means physically (e.g., mechanically, chemically, magnetically, etc.) coupled or linked and does not exclude the presence of intermediate elements between the coupled or associated items absent specific contrary language.
In view of the many possible embodiments to which the principles of the disclosed invention may be applied, it should be recognized that the illustrated embodiments are only preferred examples and should not be taken as limiting the scope of the disclosure. Rather, the scope of the disclosure is defined by the following claims. I therefore claim all that comes within the scope of these claims. | An exemplary stair nosing assembly comprises an elongated base, a plate adhered to the base, and a cover temporarily covering the base and the plate. The base has at least one anchor portion extending downwardly from the upper portion for attaching to a lip of a tread pan and/or embedding in a concrete tread. The plate can have various features to enhance traction and visibility. The cover has front and rear lips that engage with front and rear edges of the base, and a weakened region adjacent the rear lip. When the assembly is embedded in a concrete tread, the cover is configured to fracture at the weakened region when the front lip of the cover is lifted upward from the base, leaving the rear lip remaining embedded in the concrete and allowing the rest of the cover to be removed to expose upper surfaces of the base and plate. | 4 |
BACKGROUND OF THE INVENTION
The present invention relates to container construction, and particularly to a construction of a refrigerator door bin for use in refrigerator/freezer compartments.
Refrigerator door tray or bin assemblies are previously known from U.S. Pat. No. 4,859,010; U.S. Pat. No. 3,469,711; U.S. Pat. No. 2,898,173; and U.S. Pat. No. 4,921,315. However, U.S. Pat. Nos. 4,859,010 and 4,921,315 disclose unitary containers, that is, containers formed of one material including the bin portion and the collar portion. U.S. Pat. Nos. 2,898,173 and 3,469,711 disclose two level constructed containers having upper portions and lower portions connected together at a flange.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide a new method and article of manufacture, for forming a refrigerator door bin. It is an object of the present invention to provide a two piece plastic bin having respectively two different color plastics. It is an object of the present invention to provide a sturdy and rigid bin for a refrigerator door. It is an object of the present invention to provide a bin for a refrigerator door which is resistant to impact damage and which provides the required strength and durability, yet is light weight and cost effectively manufactured. It is an object of the invention to provide a door bin of plastic having a transparent container portion and an opaque sturdy collar portion surrounding the container portion, the opaque collar portion providing impact protection and rigidity to the bin and providing a hand gripping region where finger prints are less noticeable than on the transparent portion.
It is an object of the invention to provide a door bin which does not easily dislodge from its receiving space in the refrigerator door even though the bin has a depth greater than the receiving space in the door.
The objects of the invention are achieved in that a two piece bin structure and method of manufacturing thereof is provided. The bin is designed as a two piece welded assembly. Therefore, the flexibility of producing a two color door bin, particularly an opaque colored collar piece with a clear container portion, is increased. The objects are achieved in that a collar portion of the door bin is produced using a "gas assisted" injection molding process to produce a hollow beam construction for a front portion of the collar, providing increased strength along an area more susceptible to impact caused by a closing of the door against a protruding object within the refrigerator compartment.
The objects of the invention are also achieved in that the bin is provided with locking tabs to retain the bin in its receiving space allocated in the refrigerator door. The door can be provided with laterally spaced apart columns having protrusions for engaging the locking tabs. The locking tabs are arranged on a back side of the bin extending downwardly.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a refrigerator/freezer utilizing the door bin of the present invention;
FIG. 2 is a exploded perspective view of a door bin as shown in FIG. 1;
FIG. 3 is a perspective view of the door bin of FIG. 2 in assembled condition;
FIG. 4 is a partial sectional view taken generally along IV--IV of FIG. 1 showing the installed door bin in side elevation;
FIG. 5 is a plan view of the door bin as shown in FIG. 1;
FIG. 6 is a partial sectional view taken generally along VI--VI of FIG. 5;
FIG. 7 is a sectional view taken generally along line VII--VII of FIG. 5;
FIG. 8 is a partial sectional view taken generally along VIII--VIII of FIG. 5; and
FIG. 9 is an enlarged partial side view of a protrusion as shown in FIG. 4.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 illustrates a refrigerator/freezer 10 with freezer door 14 and a refrigerator door 16 shown open from the cabinet 20. Arranged on either or both of the doors 12, 14 are door bins 24. Although a vertically stacked refrigerator/freezer is shown, the door bins 24 are also applicable to side-by-side refrigerator/freezer. The bins 24 (one shown) can be supported on vertical walls 25, 26, 27 on the refrigerator door 16. Protrusions 28 are provided on inwardly directed surfaces 25a, 26a, 27a of the walls 25, 26, 27 respectively to support bins 24 at selected elevations on the door 16 as described below.
FIG. 2 shows a bin 24 having a container portion 29 having a generally rectangular rear section defined by a rear wall 30, a left side wall 32, a right side wall 34, and a floor 36. A front section is formed by the floor 36, a left lateral wall 40 and a right lateral wall 42 connected to an arcuate front wall 44 having a generally elongate C-shape.
A collar 46 having an overall horizontal profile matching the container portion 29 is placed thereon and is bonded by an adhesive or plastic welded, such as ultrasonically welded, to the container portion. The collar 46 provides a C-shaped elongate flange 48 having an inverted L-shaped cross section, integrally formed with an opposing elongate C-shaped trim 50 having an enclosed, hollow cross section. The collar 46 has an open face 46a which substantially matches an open face 29a of the container portion 29. The collar 46 also provides tabs 54, 56 extending downwardly from the flange region on opposite lateral sides of the bin 24, for mounting the bin 24 to the selected refrigerator space. The lateral walls 40, 42 create indented areas or pockets 60, 62 on opposite lateral sides of the bin 24 which receive two walls 26, 27 of the refrigerator door. The rear wall 30 extends at an upper edge into an L-shaped flange 30a with a horizontal leg 30b. The sidewall 32 extends at an upper edge into an L-shaped flange 32a with a horizontal leg 32b and an end cap 32c. The opposite sidewall 34 extends upward into an L-shaped flange 34a with a horizontal leg 34b and an end cap 34c. The flanges 32a, 34a are arranged adjacent the lateral walls 40, 42 respectively. The arcuate wall 44 extends at an upper edge into an outwardly turned lip 44a. The horizontal legs 30b, 32b, 34b flushly abut an underside 48a (FIG. 7) of the flange 48 for plastic welding thereto to connect the collar 46 to the container portion 28. The trim 50 is plastic welded to the lip 44a.
FIG. 3 shows the bin 24 in assembled condition with the collar 46 bonded to the container portion 29. In the preferred embodiment, the container portion 29 is transparent and the collar 46 is opaque and color coordinated with the refrigerator compartment.
FIG. 4 illustrates the bin 24 installed into the door 16. The tabs 54, 56 are arranged to tightly engage against two selected opposing protrusions 28 of the door 16 (see FIG. 1). The tabs 54, 56 prevent forward retraction of the bin 24 out of the door 16. The bin 24 is held tightly between the protrusions 28 and a front surface 26b, 27b of the walls 26, 27 respectively. To install the bin 24, the bin is tilted to insert the tabs 54, 56 behind the protrusions 28.
FIG. 5 illustrates the bin 24 in place in the door 16. The tabs 54, 56 are engaged behind the protrusions 28. The protrusions have a tapered profile from front to back to assist in installing the bin 24.
The clamping of the protrusions 28 and the door surfaces 26b, 27b between the tabs 54, 56 and the lateral walls 40, 42 of the bin 24 allows the bin 24 to extend substantially outwardly from the front surfaces 26b, 27b of the walls 26, 27 while resisting overturning. This provides a bin 24 which has a capacity greatly exceeding a space 73 allocated in the door 16 defined by the horizontal dividers 69, the vertical walls 26, 27 and a back wall 74 of the door 16. Also, larger items such as milk containers 75 and large condiment jars can be stored in the bin 24 which otherwise would be too large or tall for the space 73.
FIGS. 5, 6 and 7 illustrate that the tab 54 has parallel gusset stiffeners 54a,b perpendicular to the tab 54. The tab 56 has identical stiffeners arranged in mirror image to the stiffeners 54a,b.
FIG. 8 shows a section of the front generally C-shaped trim 50 which extends between the lateral walls 40, 42. The trim 50 is substantially hollow with a void 76 therein. The trim 50 is formed using a gas assisted injection molding process. The trim 50 thus forms a sturdy yet light weight surrounding member which is crush and dent resistant and provides a convenient and easy grasping handle for removing the bin 24. If the trim 50 is opaque, finger smudges are less observable than would otherwise be observed on a transparent surface.
FIG. 9 illustrates the advantageous shape of the protrusion 28 for locking the tabs 54, 56 against the door 16. The protrusions 28 are generally rectangular but with an inclined trailing face 28a for locking against the tabs 54, 56. The angle A is preferably 10°∓10°.
The invention is particularly advantageous in that the container portion 29 can be injection molded of a transparent material and the collar 46 to be secured thereto can be formed of an opaque material using the gas assisted injection molding process. The container portion 29 can be made with a more conventional injection molding process and is readily molded because of its open shape as contrasted to the finished shape of the bin 24 which may have an overhanging lip formed by the collar 46. Thus, the bin 24 can be advantageously formed by injection molding while still retaining an inwardly directed lip 78 for retaining articles within the bin 24. The collar 46 provides an increased structural rigidity to the container portion 29 through the advantage of gas assisted molding to create the hollow beam member. A two piece molding process allows that the collar 46 can be color coordinated with the remaining refrigerator cabinetry while retaining a substantially transparent bin.
Although the present invention has been described with reference to a specific embodiment, those of skill in the art will recognize that changes may be made thereto without departing from the scope and spirit of the invention as set forth in the appended claims. | A two piece bin for mounting to a refrigerator door having a transparent container portion and surrounding collar portion welded thereto, the collar portion having a portion on a front side being tubular for a light weight yet sturdy structure. The bin having an indented width to interfit within the vertical columns of the refrigerator door and an outwardly extending portion abutting an exposed end face of the vertical columns, the tubular portion of the collar arranged around this outward portion to be abutted to the vertical columns. | 5 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a numerical control processor, called herein NC processor, with an onboard grinding unit, in which a workpiece held on a work spindle is cut or machined by a Y-axis tool moved in and out with high-speed and high-acceleration in synchronized relation with a turning of the spindle, followed by being polished or finished by the grinding unit.
[0003] 2. Description of the Prior Art
[0004] There is conventionally known a lathe with an onboard grinding machine, in which a workpiece cut into a desired form can be introduced to grinding operation intact without removed from chucks on a spindle of the lathe. In Japanese Patent Laid-Open No. 7-276104, there is disclosed an example of the prior lathe with onboard grinding machine, in which a cross slide is mounted on a reciprocating carriage that is installed on a machine bed of a lathe with a feed control. A tool rest is placed on this side of a horizontal top surface of the cross slider while a motor-driven grinding wheel is placed on the far side of the horizontal top surface of the cross slider. The grinding wheel is supported on a pedestal that is fixed at a horizontal bottom thereof to the horizontal top surface of the cross slider in a way keeping an axis of the grinding wheel parallel and virtually flush with an axis of a spindle.
[0005] Moreover, there is also known an attachment used in turret lathes to allow the composite processing lathes to perform a imperfect circular machining or eccentric machining with high efficiency and high precision without making a sacrifice of specific function in the composite processing lathes. Japanese Patent Laid-Open No. 8-57702, for example, discloses the attachment of the sort stated just earlier. The prior attachment to make the imperfect circular contour and eccentric contour is fastened to any one of turning tool stations on a turret tool holder of the composite processing lathe and indexed for up to machining position where a clutch jaw on a driving shaft end in the tool holder makes engagement with another clutch jaw on a driven shaft end of the attachment. With the composite processing lathe constructed as stated earlier, a servomotor in the tool holder using NC drive to control the turning position of cutting tool actuates a rotating shaft through a rack-and-pinion drive to move the tool holder along an X-axis linear guide way, providing accurate X-axis position control relative to a turning angle of a spindle through synchronous control of a spindle motor with a rotating shaft motor to perform the imperfect circular machining or eccentric machining.
[0006] A process for producing an asymmetrically centered, aspheric surface with accuracy and very short time, using NC processors is known to those skilled in the art. The prior process is disclosed, for example in Japanese Patent Laid-Open No. 11-309602, in which a Z-axis table having a headstock thereon is kept against movement while on a processing operation. A workpiece is mounted in a chuck on the headstock to be driven with a spindle motor, while a slider having a cutting tool thereon moves in and out in a Z-axis direction under NC control. Moreover, an X-axis table supporting the slider thereon travels in a reciprocating manner in the Z-axis direction. Thus, the slider and the X-axis table are allowed to reciprocate with one another in synchronized relation with the turning of the workpiece.
[0007] The recent NC processors are designed to shape any end face and an external diameter of a workpiece into a desired complex contour with three machine axes: a turning axis of a spindle, an X-axis and a Y-axis. Programming for turning the workpiece consists of an incremental amount of movement in a specific period of time. The program for the numerical control is fed to the NC processor from any external personal computer via a high-speed bus to perform direct numerical control (DNC) operation, which performs automatic operation while on read-in of the programs through an interface. According to the DNC operation, the read-in programs may be selected and the computer numerical control (CNC) is performed while on determining the execution sequence and times of the programs. Moreover, the advanced NC processors have learning functions on the X- and Y-axes, and can be controlled for even the Z-axis in the same way as to the X- and Y-axes.
[0008] Meanwhile, the present applicant has developed the NC processor of the sort shown in FIG. 4, which is disclosed in, for example Japanese Patent Laid-Open No. 2003-94204. The NC processor is envisaged to machine a plurality of works 9 A including lenses, and so on at the same time. The NC processor is comprised of a work spindle 10 driven with a spindle motor 7 and supported for rotation on a headstock 5 arranged above a machine bed 2 , a chuck 8 clamping a jig block 17 in a relation that a turning axis thereof is in axial alignment with a turning axis of the work spindle 10 , works 9 A fastened to the jig block 17 in a way positioned circumferentially at regular intervals around the turning axis of the jig block 17 , a Z-axis table 3 supporting the headstock 5 thereon and getting moved in and out with a servomotor 6 in a Z-axis direction along the turning axis of the work spindle 10 , an X-axis table 4 moved in a reciprocating manner with a servomotor 19 in an X-axis direction that intersects with the Z-axis direction at right angles, a sliding base 1 and tool rests 23 installed on the X-axis table 4 in opposition to the headstock 10 , various X-axis cutting tools 24 mounted on the tool rest 23 , a slide block 16 fastened to sliding base 1 , a slider 18 having a Y-axis cutting tool 20 moved in a reciprocating manner over the slide block 16 in a Y-axis direction that intersects with the Y-axis direction at right angles, and driving means forcing the slider 18 to move in and out in a synchronized relation with a turning of the work spindle 10 .
[0009] With the NC processor constructed as stated just earlier, the Y-axis cutting tool 20 is used directly upon the work 9 A to machine sequentially it into a desired contour, as the slider 18 is moved in and out in the Y-axis direction in synchronized relation with the turning of the work spindle 10 in compliance with a preselected profile expected to generate sequentially on the work set up on the jig block 17 . Moreover, the slider 18 is driven to move in and out with a linear motor, which is composed of magnetic windings and field magnets allowed to move relatively to the magnetic windings, either of the magnetic windings and the field magnets being installed in the slider 18 and the other in the slide block 16 .
[0010] In the prior NC processor, the cutting tool to turn the workpiece is usually made of a diamond of single crystal, a tool nose radius R of which is ground below a specific tolerance.
[0011] With the prior NC processor to finish the work of transparent resin for optical purposes, nevertheless, any machine marks or traces caused by cutting tool remains on the processed surface of the work even after the completion of the cutting operation, thereby resulting in taking away commercial value from the products. To deal with this issue as stated earlier, the products have to be post-treated of attempting to grind the machined surface of the work to produce a high-quality surface finish on the workpiece.
[0012] In the conventional processors of the sort stated earlier, accordingly, the workpiece commonly is first machined to generate a desired profile or contour thereon and then subject to the surface finishing process to remove any scratches and machine marks from the machined surface of the workpiece. Generally, the profile generating process and the surface finishing process are performed, using respective special-purpose machines. This is because two categories of first process for generating any desired contour on the work and the second process or honing process for removing any roughness from the machined surface of the workpiece are distinct in processing technique from one another and therefore can not be realized by only a single processor. Thus, the workpiece has to be removed from the profile generating machine after the completion of the profile generating process and then set on the surface finisher. Handling the workpiece between the distinct processors has caused decreasing the available percentage of the finished product.
[0013] Moreover, the workpiece cut into any desired contour has to be reset on another processor. To do this, the workpiece is needed to go through some troublesome process of attempting to get the centre of the workpiece to align accurately with the turning axis of the processor. This reset of the workpiece to the processor would result in raising the percent defective of the products. That is to say, it is almost impossible to align the contour on the workpiece throughout both the preceding process for generating any desired contour on the workpiece and succeeding process to produce the high-quality surface finish. To cope with this, the second process of honing operation is needed to remove a relatively much amount of substance, including a margin of error that would occur due to the reset of the workpiece, from machined surface of the workpiece. This means it would take plenty of time to finish a workpiece while there would be inevitable some discrepancy between the preselected contour and the finished one. This discrepancy could cause any inferior products that are out of conformity to the original design specifications, reducing the available percentage of the finished products.
SUMMARY OF THE INVENTION
[0014] The present invention, therefore, has as its primary object to solve the major problems as described just above and more particular to provide a numerical control (NC) processor with an onboard grinding unit, in which a workpiece of synthetic resin and so on is cut accurately in an aspheric contour with a high-speed, high-accelerated Y-axis cutting tool mounted on a slider that is small in inertia force sufficiently to ensure high-speed reciprocating motion, and at once subjected to precise honing operation intact without removed from a chuck in conformity to a desired contour for removing machine marks from a machined surface of the workpiece to finish the workpiece within close size limits whereby both the cutting and honing operations can be performed with just a single processor.
[0015] The present invention is concerned with an NC processor with onboard grinding unit; comprising a work spindle supported for rotation on a headstock, chucking means installed on the work spindle to hold a workpiece therein, a Z-axis table having mounted thereon with the headstock and allowed to move in a Z-axis direction lying along an axial direction of the work spindle, an X-axis table allowed to move in an X-axis direction perpendicular to the Z-axis direction, a sliding base fastened to the X-axis table, a slider allowed to move back and forth over the sliding base in a Y-axis direction perpendicular to the X-axis direction, a Y-axis cutting tool installed on the slider to cut the workpiece, a grinding unit installed on the X-axis table in close proximity to the sliding base, and a controller to regulate all the work spindle, the X-axis table and the slider; wherein the controller regulates reciprocating movements of the slider, X-axis table and the Z-axis table in synchronized relation with the rotation of the work spindle so as to first cut the workpiece with the Y-axis cutting tool into a preselected contour, and then finish a work surface of the workpiece with the grinding unit in conformity with a programmed contour while the workpiece remains held in the chucking means even after preceding cutting operation.
[0016] In an aspect of the present invention, there is provided an NC processor with onboard grinding unit in which the slider is allowed to move back and forth over the slide block lying on the sliding base in a Y-axis direction perpendicular to the X-axis direction.
[0017] In another aspect of the present invention, an NC processor with onboard grinding unit is provided in which the slide block is made thereon with a guide rail extending in the Y-axis direction, on which the slider lies in a way moving back and forth by virtue of electromagnetic force of a linear motor along the guide rail in the Y-axis direction with high speed and high acceleration and the linear motor is composed of magnetic windings and field magnets, either of the magnetic windings and the field magnets being installed in the slide block and the other in the slider.
[0018] In another aspect of the present invention, an NC processor with onboard grinding unit is provided in which the controller regulates a cutting operation depending on programming consisting of a revolution of the work spindle along with data indicating locations of a tool tip of the Y-axis cutting tool in the Y-axis direction.
[0019] In a further another aspect of the present invention, there is provided an NC processor with onboard grinding unit in which the controller lets the Y-axis cutting tool turn the workpiece in the somewhat rough contour with grinding allowance, and then causes the grinding unit rather than the Y-axis cutting tool to remove the grinding allowance from the work surface of the workpiece in conformity with the programmed contour.
[0020] In another aspect of the present invention, an NC processor with onboard grinding unit is provided in which the grinding unit is comprised of a buffing base fastened to the X-axis table, a nozzle mounted on the buffing base to apply an aqueous or oily cutting fluid to the work being processed, a motor mounted on a support that is secured on the buffing base, a tool spindle connected drivingly to the motor through a reduction gear, and a buffing material mounted on the tool spindle to grind the workpiece.
[0021] In a further another aspect of the present invention, there is provided an NC processor with onboard grinding unit in which mist of the cutting fluid is ejected from the nozzle against the work surface of the workpiece while being ground into a desired contour.
[0022] In another aspect of the present invention, an NC processor with onboard grinding unit is provided in which the workpiece is a lens blank, which adheres to a lens fixture grasped with the chucking means.
[0023] In another aspect of the present invention, an NC processor with onboard grinding unit is provided in which an X-axis cutting tool held on a cutting tool rest mounted on the X-axis table first rough cuts the workpiece in a contour approximate to the desired contour, which is in turn finished with the Y-axis cutting tool to produce a high-quality surface finish.
[0024] With the NC processor with onboard grinding unit constructed as stated earlier, the slider is allowed to follow well the desired reciprocating motions with high speed and high acceleration, compared with the prior NC processor in which the motor's rpm to drive a ball screw is controlled by position feedback of data representing locations monitored with an encoder, so that the high rpm of the work spindle makes it possible to turn the workpiece with high speed and high acceleration. According to the present invention, moreover, the workpiece after having been cut in a preselected contour is subject to the grinding operation at once while remaining held in the chucking means intact. This makes sure of cutting the running hours needed for grinding operation.
[0025] Although the NC processor of the present invention will work with either of a linear motor and a servomotor to get the slider moving in and out, the linear motor is preferable to move the slider with high speed and high acceleration. Selection of the linear motor rather than the servomotor is because that the reciprocating slider itself can be made very small in weight so that an inertia force in the slider is curbed largely to the extent allowing the slider to follow well the high rpm the work spindle. Thus, the slider can be driven with good response to the high speed and high acceleration, thereby making sure of cutting accurately the workpiece with a very short time.
[0026] With the NC processor with onboard grinding unit constructed as stated earlier, the workpiece of, for example synthetic resin is first turned accurately in a preselected profile like asymmetrically centered, aspheric contour with a high-speed, high-accelerated Y-axis cutting tool within a very short time, and at once subjected to precise honing operation intact without removed from the chucking means, thereby to remove machine marks left by the Y-axis cutting tool on a machined surface of the workpiece to finish the workpiece within close size limits.
[0027] According to the NC processor with onboard grinding unit of the present invention, the workpiece grasped in the chucking means is first machined with the Y-axis cutting tool, and then the workpiece only machined while remaining held in the chucking means intact is ground to the final form with the grinding unit installed on the same sliding base as the Y-axis cutting tool. Thus, the workpiece can be processed accurately at both the cutting and grinding operations within a very short working time. Since there is no possible damage to the workpiece that might occur when the workpiece is reset in the chucking means from the cutting operation to the grinding operation, any unforeseen accident may be prevented in advance and therefore capital investment will be cut down.
[0028] In the NC processor in which the slider is constituted with a linear motor, the slider itself can weigh less, thus reducing in inertia force. The slider is improved in following and response abilities conformable to the high rpm of the work spindle. Thus, the slider can be driven to get the Y-axis cutting tool shaping the workpiece with the high speed and high acceleration, thereby making sure of cutting accurately the workpiece with a very short time.
BRIEF DESCRIPTION OF THE DRAWINGS
[0029] [0029]FIG. 1 is a schematic top plan view explaining an NC processor with an onboard grinding unit in accordance with the present invention:
[0030] [0030]FIG. 2 is a fragmentary front elevation, partly in section, of the grinding unit installed in the NC processor of FIG. 1:
[0031] [0031]FIG. 3 is a fragmentary plan view, partly in section, of the grinding unit of FIG. 2: and
[0032] [0032]FIG. 4 is a top plan view illustrating a prior NC processor to machine a plurality of works at the same time.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0033] A preferred embodiment of an NC processor with an onboard grinding unit according to the present invention will be explained hereinafter in detail with reference to the accompanying drawings. Compared with the prior NC processor shown in FIG. 4, a work spindle, a Z-axis table movable in a Z-axis direction and an X-axis table allowed to move along an X-axis direction are the same as previously described. To that extent, these components have been given the same reference characters, so that the previous description will be applicable.
[0034] The NC processor with onboard grinding unit according to the present invention has, for example a Z-axis table 3 allowed to move in a Z-axis direction extending lengthwise of a work spindle 10 over a Z-axis guide way 33 mounted on a machine bed 2 , and an X-axis table 4 movable along an X-axis direction perpendicular to the Z-axis direction over an X-axis guide way 32 installed on the machine bed 2 . A headstock 5 rests on the Z-axis table 3 , which is driven with a servomotor 6 installed on the Z-axis guide way 33 on the machine bed 2 , moving back and forth in the Z-axis direction. The headstock 5 is mounted on the Z-axis table 3 that is allowed to travel in the Z-axis direction lying lengthwise of the work spindle 10 . The headstock 5 has incorporated with a spindle motor 7 to turn the work spindle 10 , on an extremity of which is provided chucking means where the work 9 is held to get turned while on a rotation of the work spindle 10 .
[0035] Moreover, the X-axis table 4 is disposed on an X-axis guide way 32 on the machine bed 2 in opposition to the workpiece 9 clamped in the chucking means 8 of the work spindle 10 in such that the X-axis table 4 is allowed to move in the X-axis direction perpendicular to the Z-axis direction along which the Z-axis table 3 will move linearly. The X-axis table 4 has mounted thereon with a sliding base 1 , a grinding unit 11 near the sliding base 1 , and a cutting tool rest 23 installed near to the grinding unit 11 and provided thereon with a variety of X-axis tools 24 .
[0036] On the sliding base 1 , there is fastened the slide block 16 that is composed of, for example a pair of slide block members having lengthwise recesses, one to each member. The slide block 16 is built on the sliding base 1 , for example in such a construction that the slide block members, although not shown, are arranged with their lengthwise recesses facing each other and also any one of the block members is caused to bear against a step on the sliding base 1 while the block members are fastened using a widthwise spacer block on the sliding base 1 , with their confronting surfaces being brought into abutment against one another.
[0037] The NC processor of the present invention features that the workpiece 9 is first turned with a Y-axis cutting tool 20 into a desired contour as the work spindle 10 rotates on its axis, and then honed or lapped with the grinding unit 11 . It is to be noted that the wording “honing or lapping operation with the grinding unit 11 ” discussed herein rules out any turning or cutting operation to change substantially the contour or profile machined on the workpiece 9 . The NC processor of the present invention has the work spindle 10 installed for rotation in the headstock 5 arranged on the machine bed 2 , the workpiece 9 held in the chucking means 8 on the work spindle 10 , the Z-axis table 3 having mounted thereon with the headstock 5 and able to move in the Z-axis direction extending along the turning axis of the work spindle 10 , the X-axis table 4 allowed to move in the X-axis direction perpendicular to the Z-axis direction, the sliding base 1 fastened to the X-axis table 4 in opposite relation to the work spindle 10 , a slider 18 allowed to move in and out along a Y-axis direction perpendicular to the X-axis direction, or the same direction as the Z-axis direction, over the slide block 16 supported on the sliding base 1 , the Y-axis cutting tool 20 mounted on the slider 18 to cut the workpiece 9 , the grinding unit 11 mounted on the X-axis table 4 in close relation to the sliding base 1 in a way opposing the work spindle 10 , and a controller, not shown, to activate all the Z-axis table 3 , X-axis table 4 and the slider 18 in synchronized relation with the turning of the work spindle 10 .
[0038] The controller regulates a reciprocating motion of the slider 18 in synchronized relation with the turning of the work spindle 10 to turn or cut the workpiece 9 with the Y-axis tool 20 into a preselected desired contour. Then, the workpiece 9 can experience the lapping or honing operation in a situation stayed held in the chucking means 8 without removed from the chucking means 8 preparatory to the succeeding grinding operation. There the controller regulates the grinding unit 11 to grind a chipped work surface 31 in conformity with a programmed contour.
[0039] More particular, the controller is designed to regulate the turning operation depending on programming consisting of a revolution of the work spindle 10 along with data indicating locations of a tool tip of the Y-axis cutting tool 20 in the Y-axis direction. Moreover, the controller is programmed to first move the slider 18 with onboard Y-axis cutting tool 20 in a sliding manner over the sliding base 1 to a location where the Y-axis cutting tool 20 is applied directly on the workpiece 9 held in the chucking means 8 , then machining the workpiece 9 with the Y-axis cutting tool 20 into the preselected contour, thereafter bring the grinding unit 11 on the X-axis table 4 to the workpiece 9 that has been cut just once while remaining held in the chucking means 8 , then honing or lapping the machined work surface 31 of the workpiece 9 to produce a high-quality surface finish.
[0040] With the NC processor of the present invention, in particular, the controller lets the Y-axis cutting tool 20 turn the workpiece 9 in the somewhat rough contour with grinding allowance of, for example from mere tenths of a few μm to a few μm. Then, the controller causes the grinding unit 11 rather than the Y-axis cutting tool 20 to grind the work surface 31 of the workpiece 9 in conformity with the programmed contour, thereby improving the surface roughness of the work surface 31 of the workpiece 9 turned previously in the preceding process with the Y-axis cutting tool 20 . For controlling the process to grind the work surface 31 of the workpiece 9 , some parameters including selection of buffing material 27 in conformity with synthetic resin of the workpiece 9 , and turning velocity of the work spindle 10 to rotate the buffing material 27 , are set adequately. With the grinding operation of the work surface 31 of the workpiece 9 with the grinding unit 11 in the NC processor of the present invention, moreover, the controller makes use of the learning function and DNC operation to finish the work surface 31 with fidelity. Besides, when the finished surface of the workpiece 9 like lens has need of, for example any coating after the completion of the honing operation of the work surface 31 , the surface roughness of the work surface 31 may be regulated to make the coating on the honed surface easier.
[0041] The grinding unit 11 is comprised of a buffing base 12 , a nozzle 13 mounted on the buffing base 12 to apply aqueous coolants or oily cutting fluids to the workpiece 9 being processed, a motor 21 mounted on a support 14 that is secured on the buffing base 12 , a tool spindle 30 connected drivingly to the motor 21 through a reduction gear, and the buffing material 27 mounted on the tool spindle 30 to grind the work surface 31 of the workpiece 9 .
[0042] With the grinding unit 11 constructed as stated earlier, the cutting fluids of, for example either mist cooling or conventional fluid cooling selected depending on materials of the workpiece 9 are ejected from the nozzle 13 against the work surface 31 of the workpiece 9 being ground and to the grinding tool in order to keep both the workpiece 9 and the grinding tool cool. Of course, the cutting fluids of aqueous solutions may contain some abrasives, depending on the type of product and the operation.
[0043] Infeed mode to feed the buffing material 27 into the work surface 31 of the workpiece 9 being cut into the desired contour can be selected properly from among a fixed feed rate mode, a random feed rate mode and an oscillating feed mode, depending on the desired profile on the work surface 31 . Pressure to force the buffing material 27 against the work surface 31 of the workpiece 9 being cut into the desired contour can be chosen adequately from among a constantly controlled pressure and a randomly variable pressure.
[0044] On the support 14 , there is mounted an overhang 29 in which an L-shaped head 15 is held. The L-shaped head 15 includes the motor 21 , the reduction gear 22 to get the rpm of the motor 21 reducing, a spindle holder 25 bearing therein for rotation the tool spindle 30 that is turned with the output from the reduction gear 22 , a collet chuck 26 to grasp the tool spindle 30 , and the buffing material 27 secured to the free end of the tool spindle 30 .
[0045] The workpiece 9 is a lens blank of synthetic resin and so on, which adheres to a lens fixture 28 grasped with the chucking means 8 . The X-axis cutting tool 24 held on the cutting tool rest 23 mounted on the X-axis table 4 first rough cut the workpiece 9 into a contour approximate to the desired profile, which is in turn finished with the Y-axis cutting tool 20 to produce a high-quality surface finish.
[0046] The slide block 16 is made thereon with guide rails, not shown, extending in the Y-axis direction, on which the slider 18 lies in a way moving back and forth with the electromagnetic driving power of a linear motor along the guide rail in the Y-axis direction with high speed and high acceleration. The driving means to move in and out the slider 18 in the Y-axis direction can be constituted with, for example, a linear motor of the sort, not shown, which is disclosed in, for example Japanese Patent Laid-Open No. 2002-126907 filed earlier by the present applicant. With the embodiment discussed here, the linear motor is composed of magnetic windings and field magnets allowed to move relatively to the magnetic windings, either of the magnetic windings and the field magnets being installed in the slider 18 and the other in the slide block 16 . Fastened on the slide block 16 are the guide rails at several locations to provide linear guide ways extending in the Y-axis direction, which is the same direction as the Z-axis direction, perpendicular to the X-axis direction on the sliding base 1 . The slider 18 has sliding elements, by virtue of which the slider 18 is allowed to move in and out in the Y-axis direction with high speed and high acceleration.
[0047] There is provided a linear scale extending over a span where the slider 18 is allowed to move in and out, and a sensor responsive to the linear scale. The sensor quickly determines an amount of movement of the slider 18 relative to the slide block 16 to provide an input to the controller. It then adjusts the subsequent movement of the slider 18 on feedback from the sensor. The controller equipped in the NC processor of the present invention has a learning function compensating for deviation of a preselected cutting instruction from current cutting information based on feedback of an actual cutting information resulting from current cutting operation where the Y-axis cutting tool 20 on the slider 18 cuts the workpiece 9 depending on a value representing the preselected cutting instruction, and then getting the compensated mode reflecting in next cutting operation. The controller, moreover, has a predicted function getting the Y-axis cutting tool 20 on the slider 18 cutting the workpiece 9 with any previously stored cutting capabilities in mind.
[0048] Although the NC processor with onboard grinding unit of the present invention has been described in the embodiment in which the Z-axis table 3 has mounted thereon with the headstock 5 while the X-axis table 4 has mounted with the grinding unit 11 , the Y-axis cutting tool 20 and the cutting tool rest 23 , it will be understood that the same is said for the construction in which the X-axis table 4 , conversely, has mounted thereon with the headstock while the Z-axis table 3 has mounted with the grinding unit, the Y-axis cutting tool and the cutting tool rest. Having described the present invention as related to just one tool rest 23 on the X-axis table 4 , it will be appreciated that any number of the tool rests may be used and also any number of cutting tools can be equipped on the tool rests.
[0049] As the present invention may be embodied in several forms without departing from the spirit of essential characteristics thereof, the present embodiments are therefore illustrative and not restrictive, since the scope of the invention is defined by the appended claims rather than by the description preceding them, and all changes that fall within meets and bounds are therefore intended to embraced by the claims. | A numerical control (NC) processor with an onboard grinding unit is disclosed in which a workpiece is first cut in a preselected contour with a Y-axis cutting tool, and then subjected to honing operation intact whereby both the cutting and honing operations can be performed with just a single processor with high-speed, high-acceleration. With the NC processor, the Y-axis cutting tool is mounted on a sliding base above an X-axis table in a way allowed to move back and forth in a Y-axis direction, while a grinding unit is installed in close proximity to the sliding base. A slider moves back and forth in synchronized relation with rotation of a work spindle to first let the Y-axis cutting tool cut the workpiece into a preselected contour, and then cause a buffing material of the grinding unit to grind a work surface of the workpiece into a high-quality surface finish in conformity with a programmed contour while the workpiece remains held intact in chucking means. | 8 |
BACKGROUND OF THE INVENTION
This invention relates to twist drills, and more particularly but not necessarily exclusively to twist drills for producing holes of high accuracy in materials that are difficult to work, especially hard materials.
A conventional twist drill comprises a cylindrical drill body provided with a pair of helical flutes defining fluted lands between them and extending from the cutting point of the drill to a shank at the other end, by which shank the drill is securable in a chuck, for example, of a hand tool, or a drilling machine. The cutting point of the drill is of generally conical-shape, with a central chisel edge from which a pair of diametrically opposed cutting edges defined by the leading faces of the fluted lands and the flanks of the drill point that form the end faces of the fluted lands. The outer periphery of each fluted land has at its leading edge a radial projection which is variously termed a land, a cylindrical land, a wear margin, or a support margin. These two support margins extend along the length of their fluted lands and are intended to guide the drill radially as it forms a hole.
In conventional twist drills, there is a tendency to chatter, which can lead to the wall of the hole being drilled having grooves or tracks. The circularity and straightness of a hole produced by a conventional twist drill are also often inadequate for many applications. These defects are particularly pronounced when drilling very hard materials, and necessitate a subsequent reaming operation where dimensional accuracy of the hole is required.
It has been recognized that the use of only two support margins is inadequate for guiding the drill in its hole in certain applications. For example, in U.S. Pat. No. 4,913,603 there is provided a twist drill having three support margins, one at the leading edge of each of the two fluted lands and one of the fluted lands being wider than the other at its radially outer face and having a further support margin at its trailing edge to give three-point guidance. This prior art drill is also required to have cutting edges at unequal spacings. The fluted lands are therefore asymmetrical in transverse cross-section which is generally undesirable, and in any event the arrangement still does not provide adequate stability for many applications.
In British Patent 1,432,546 there is described a twist drill having symmetrical pairs of flutes and fluted lands, each of the two fluted lands having support margins at both its leading and trailing edges. Each leading edge support margin is relieved in the region nearest the drill point, so that the trailing edge support margin is required to have a cutting action widening the hole to the full diameter of the drill. This construction, however, does not overcome the instability problem encountered in drilling very hard materials.
A particular application where difficulties of accuracy of drilling have arisen is in the preparation of rock drill bits for mining applications. Rock drill bits have bodies made from very hard steels, of a generally bulbous construction, with a number of wear resistant hard metal teeth embedded in the front face of the body. The teeth or studs are inserted with an interference fit into holes drilled in that front face. At present the holes need to be drilled and then reamed to provide sufficient accuracy and a sufficiently good surface finish for the teeth or studs to be a firm fit within them. However, even the use of a reamer cannot rectify the problem caused by a hole that has not been drilled sufficiently straight.
There is therefore a need for a drill which can provide holes of improved circularity, surface finish and straightness, to close tolerances, particularly when drilling materials which are difficult to work, and especially hard materials.
SUMMARY OF THE INVENTION
According to the invention, there is provided a twist drill comprising a drill body having a plurality of helical flutes between fluted lands extending along the body to a leading end of the drill, each said fluted land having a plurality of circumferentially spaced support margins projecting from its radially outer face, at least one of the support margins being asymmetrically spaced with respect to the other support margins.
The twist drill is conveniently formed with two helical flutes between two diametrically opposite and symmetrically disposed fluted lands, each having a pair of spaced support margins.
Preferably, the profile of each helical flute is such that the drill is provided at its cutting end with two convex curved cutting edges, in the manner disclosed in British Patent 2,184,046.
For drilling hard materials, as already referred to, the material of the drill tip preferably comprises hard metals such as tungsten carbide. In particular instances it may be preferred for the drill to have a steel shank with a tungsten carbide tip.
Twist drills according to the invention are preferably provided with a wear-resistant coating, which can, for example, be a nitride or carbide coating or combinations thereof. The coating may be multi-layered, for example, the inner layers functioning to promote adhesion of the coating to the drill body and the outer layers providing wear-resistant characteristics.
The central web of a drill according to the invention is preferably thinned to produce secondary cutting edges which have a negative axial rake of 1-4°.
In certain applications, and particularly for drilling holes in the body of a rock drill bit, it is advantageous to round the radially outer end of the cutting edge of each fluted land. The end face of the hole cut by the drill is then given a radiused junction with the peripheral wall of the hole to reduce the stress concentration at that region.
As with conventional drills, twist drills according to the invention can have internal holes or galleries which extend along the length of the fluted land for lubrication of the cutting action.
An embodiment of the invention will now be described, by way of example, with reference to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows an end elevational view of the cutting end face of a twist drill according to the invention;
FIG. 2 is a similar view, to a larger scale, of the central region of the drill end face;
FIG. 3 shows a side elevational view of the leading end of the twist drill of FIG. 1 in the direction III in FIG. 2; and
FIG. 4 is a similar side elevational view of the drill tip, to a slightly larger scale, in the direction IV in FIG. 2.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to the drawings, the twist drill 1 has a body 2 provided with two diametrically opposite flutes 4 with a 30° helix angle bounding diametrically opposite fluted lands 6. The cutting point 8 on the leading end of the drill has a point angle of 140°. The leading faces 10 and end faces 12 of the fluted lands form primary cutting edges 14 which are convexly curved in the manner disclosed in British Patent 2,184,046 to which reference can be made for further details. At the outer edge of the fluted lands 6 the main cutting edges 14 have a negative radial rake.
Each end face 12 has, immediately adjacent the cutting edge 14, a relatively narrow portion 12a at a moderate positive rake of 6-8° and a wider portion 12b more steeply raked at about 17-25°. In the central web of the drill between the two fluted lands the cutting point has diametrically opposite reliefs 16 steeply raked to form secondary cutting edges 18 with the portions 12a of the end faces 12. These secondary cutting edges have a negative axial rake 8 of 1-4°. The reliefs 16 thin the central web to leave only a very small chisel edge 20 at the center of the cutting point.
As FIG. 2 shows, relative to a diametrical datum line parallel to the mean orientation of the primary cutting edge 14, the chisel edge 20 lies at an angle α, which is preferably in the range 102-110°, and secondary cutting edge 18 lies at an angle β, which is preferably in the range 135-140°.
At their radially outer ends 26 the main cutting edges 14 are rounded to round the junction between the bottom and peripheral walls of the hole being drilled.
The outer peripheral faces of the fluted lands 6 have pairs of support margins 21, 22, 23, 24 projecting radially to the nominal diameter of the drill. A first support margin 21,22 is located immediately adjacent the leading edge of each fluted land and the main cutting edges 14 continue across the front of these support margins. On one fluted land, the second support margin 23 lies immediately adjacent its trailing edge. On the other fluted land, the second support margin 24 is spaced from both leading and trailing edges. The non-symmetrical arrangement of the support margins has been found to contribute substantially to the stability of the drill in operation.
Each cutting edge is chamfered to form a narrow leading face 28 at a small negative rake. Also, the heel corners of the two fluted lands are chamfered, as indicated at 30.
The drill may have a wear-resistant coating, such as of titanium nitride.
Preferred dimensions of twist drills formed in the manner described are as follows:
Helix angle 25° to 40°, for example about 30°,
Point angle 125° to 150°, preferably about 140°;
Combined fluted land width (measured at the periphery at right-angles to the drill helix), 60% to 80% of the nominal diameter of the drill;
Combined support margin width, 10% to 20% of the nominal diameter of the drill.
Examples of twist drills with the features described have been found to give improved stability during drilling, substantially reducing chattering, and improved hole concentricity.
The performance of a conventional solid carbide or carbide tipped helical drill is generally rated good if it can maintain roundness tolerance of the order 20 microns on an 11 mm diameter hole. Using a drill according to the illustrated example, it has been found that the roundness tolerance can be reduced to 5 microns or less on a 11 mm diameter hole. In addition it has been found possible to obtain up to 2 to 3 times the drill life, and double the penetration rates of conventional tooling. It has also been found that the holes can be drilled very close to size, with good consistency, very little ovality and parallel sides.
Such holes can be drilled with an accuracy of hole size and straightness, and a surface finish comparable with those produced by conventional drills which are completed by a secondary reaming operation. Increased feed rates over conventional tooling can also be achieved, together with a smaller, controlled chip formation.
Twist drills in accordance with the invention can be used in a wide variety of applications requiring improved hole accuracy and good hole surface finish. | A helical twist drill has fluted lands each having projecting from their radially outer faces a plurality of circumferentially spaced support margins. At least one of the support margins is asymmetrically spaced with respect to the other support margins. | 1 |
FIELD
The present disclosure relates to target wheels for sensors as used in mechanical devices, and more particularly to plastic target wheels incorporating ferrous material.
BACKGROUND
The statements in this section merely provide background information related to the present disclosure and may or may not constitute prior art.
In mechanical devices such as power transmissions, engines or other machines, efficient control of the operation of the device often relies on a controller receiving data from sensors within the device. A transmission controller, for example, may require the rotational speed of an internal gear, shaft or other rotating member. Typically, this is accomplished using a speed target wheel rotationally secured to such a shaft or member and a sensor targeting the speed target wheel. The speed target wheel is generally ferrous and includes target teeth that are detected by the sensor as they rotate past the sensor. The sensor is positioned to target the radial surface of the teeth of the speed target wheel. Metal target wheels are often heavy, relatively expensive, and may require complex cutting or shaping procedures to create a suitable target.
Accordingly, there is a need for a lightweight and relatively inexpensive speed target wheel.
SUMMARY
A speed target wheel includes an annular body portion and a plurality of gear teeth. The annular body portion consists of a plastic material and the plurality of gear teeth project from the annular body portion. Each of the plurality of gear teeth includes a base portion adjacent the annular body portion and a tip portion, where the base portion is integrally formed with the annular body portion and substantially comprises the plastic material, and where the tip portion includes a ferrous region integrally encompassed by the plastic material.
In another example of the present invention, the ferrous region of the plurality of gear teeth is disposed adjacent an outer radial surface of the tip portion of the plurality of gear teeth.
In yet another example of the present invention, the ferrous region includes a ferrous member.
In yet another example of the present invention, the plurality of gear teeth have a predefined width and the ferrous member has a length that is substantially similar to the predefined width.
In yet another example of the present invention, the ferrous member is substantially cylindrically shaped.
In yet another example of the present invention, the ferrous member is substantially the size of the tip portion of each of the plurality of gear teeth.
In yet another example of the present invention, an outer surface of each ferrous member is partially exposed at an outer radial portion of the speed target wheel at the tip portion of each of the plurality of gear teeth.
In yet another example of the present invention, the ferrous region includes a plurality of ferrous particles interspersed in the plastic material of the plurality of gear teeth.
In yet another example of the present invention, at least a portion of the plurality of ferrous particles is exposed along an outer surface of the gear teeth.
In yet another example of the present invention, the body portion includes a smooth inner surface for press fitting on a shaft.
In yet another example of the present invention, the ferrous region is included in each of the gear teeth in an amount and is disposed at a location that is effective to generate a signal in a Hall effect sensor disposed for reading the movement of the ferrous region.
In yet another example of the present invention a method of manufacturing a speed target wheel is provided. The method includes providing an injection molding form having a body form portion and a tooth form portion for creating an annular speed target wheel, inserting ferrous material into the tooth form portion of the injection molding form, injecting plastic into the injection molding form to create an annular plastic target wheel having gear teeth with embedded ferrous material, and removing the annular plastic target wheel from the injection molding form.
In yet another example of the present invention the method further includes removing an outer portion of the gear teeth to expose the embedded ferrous material.
In yet another example of the present invention the method further includes inserting the ferrous material into the tooth form portion of the injection molding form at an outer radial portion of the injection molding form at the tooth form portion.
Further aspects and advantages of the present disclosure will become apparent by reference to the following description and appended drawings wherein like reference numbers refer to the same component, element or feature.
DRAWINGS
The drawings described herein are for illustration purposes only and are not intended to limit the scope of the present disclosure in any way;
FIG. 1 is a schematic view of an example of a speed sensor assembly according to principles of the present invention;
FIG. 2 is a side view of an example of a speed target wheel according to principles of the present invention;
FIG. 3 is an enlarged view of a portion of an example of a speed target wheel according to principles of the present invention;
FIG. 4 is an enlarged view of a portion of an example of a speed target wheel according to principles of the present invention; and
FIG. 5 is a flow chart of an example of a method of manufacturing a speed target wheel according to principles of the present invention.
DETAILED DESCRIPTION
The following description is merely exemplary in nature and is not intended to limit the present disclosure, application, or uses.
Referring to the drawings, wherein like reference numbers refer to like components, in FIG. 1 an example of a speed sensor assembly 10 for determining the speed of a shaft 12 is illustrated according to principles of the present invention. The speed sensor assembly 10 includes a speed target wheel 14 rotationally secured to the shaft 12 and a sensor 18 disposed to read the speed target wheel 14 . The shaft 12 is generally a shaft, carrier, hub, or other rotating component of a vehicle transmission whose rotational speed is to be measured. The transmission may be automatic, manual, dual clutch, or other types of transmissions without departing from the scope of the present invention. It should be appreciated that the sensor assembly 10 may be used in Power Take Off Units (PTU's), Center & Rear Differentials, and Vehicle Wheel Speed Sensors without departing from the scope of the present invention.
Referring now to FIGS. 2 and 3 , and with continued reference to FIG. 1 , the speed target wheel 14 is shown in several views in accordance with principles of the present invention. The speed target wheel 14 generally has a plastic molded body portion 20 and a plurality of gear teeth 24 . An inner surface 22 of the body portion 20 is press fit onto the shaft 12 to cause the shaft 12 and the target wheel 14 to rotate at substantially the same speed. In alternative embodiments the inner surface 22 of the target wheel 14 includes splines (not shown) to engage with splines (not shown) formed on the shaft 12 . Each of the gear teeth 24 includes a ferrous object or ferrous member 25 and a target surface 26 that faces radially outward from the target wheel 14 . The ferrous member defines a ferrous region of each of the gear teeth 24 . The ferrous member 25 is at least partially integrally encompassed or surrounded by a plastic that forms the remainder of the gear tooth 24 . In the example provided the ferrous member 25 is a cylinder having a diameter of several millimeters and a length of several millimeters and is integrally encompassed by placement in an injection molding form during molding of the target wheel 14 , as will be described below. It should be appreciated that other shapes and sizes of objects may be used without departing from the scope of the present invention. The target surface 26 may include a portion of the outer surface of the ferrous member 25 . For example, the plastic outer diameter portion of the target wheel 14 may be removed by abrasion, cutting, or other methods to expose a portion of the outer surface of the ferrous member 25 after the target wheel 14 has been molded. In alternative embodiments the outer portion of each gear tooth 24 is retained, and the ferrous member 25 is large enough to alter the field of the sensor 18 through a layer of plastic.
The sensor 18 generally detects changes in a magnetic field to determine when each gear tooth 24 passes by the sensor 18 . The sensor 18 is generally fixed or securely attached to a transmission housing (not shown). The sensor 18 actively detects the ferrous member 25 in the target to determine speed. The sensor 18 generates a signal induced by the rotation of the speed target wheel 14 and the ferrous member 25 embedded in each gear tooth 24 . The sensor 18 may be of various types and the magnetic field may be generated in various ways without departing from the scope of the present invention. In accordance with one example of the present invention, the sensor 18 is a Hall effect type sensor.
The sensor outputs a signal through a wire 30 that indicates the speed of the target wheel 14 . The sensor 18 is positioned within close proximity of the target surface 26 of the target wheel 14 . The distance between the speed target wheel 14 and the sensor 18 creates an air gap. The continuous rotation of the speed target wheel 14 —and thus the passage of gear teeth 24 past the sensor 18 —causes the sensor 18 to detect a continuous change of the magnetic field. The change in the magnetic field in the sensor 18 induces a signal in the wire 30 that is indicative of the speed of the speed target wheel 14 and the shaft 12 .
A controller 32 is in electronic communication with the wire 30 to detect the signal current from the sensor 18 . The controller 32 is preferably an electronic device having a preprogrammed digital computer or processor, control logic, memory used to store data, and at least one I/O peripheral. However, other types of controllers may be employed without departing from the scope of the present invention.
Referring now to FIG. 4 , a portion of an alternative embodiment of a target wheel 14 ′ is shown in accordance with principles of the present invention. The target wheel 14 ′ is substantially similar to the target wheel 14 and may be used with the shaft 12 and the sensor 18 as previously described. The target wheel 14 ′ includes a plastic body portion 20 ′ and a plurality of gear teeth 24 ′. The gear teeth 24 ′ each include a ferrous region or region of ferrous particles 25 ′. The ferrous particles 25 ′ are included near an outer diameter of the target wheel 14 ′ and are at least partially exposed on an outer surface 26 ′ of the gear teeth 24 ′. For example, the region of ferrous particles 25 ′ may be added to a tooth region of a mold for injection molding plastic. The outer surface 26 ′ is preferably ground to expose the ferrous particles 25 ′ after molding the target wheel 14 ′. The region of ferrous particles 25 ′ alter a magnetic field when passing the sensor 18 , which in turn generates a signal indicative of the speed of the target wheel 14 ′ and the shaft 12 .
Referring now to FIG. 5 , a method of manufacturing a target wheel is indicated by reference number 100 . At step 102 an injection molding form is provided. The injection molding form has a body form portion and a tooth form portion to create a speed target wheel. In step 104 , ferrous material is inserted into the tooth form portion of the injection molding form. For example, the ferrous member 25 or the ferrous particles 25 ′ may be inserted into the tooth form portion near an outer diameter of the injection molding form. In one example the ferrous material is positioned in the tooth form portion by magnetizing a portion of the mold.
In step 106 , plastic is injected into the injection molding form to create a plastic target wheel. The injection creates a plastic target wheel that has gear teeth with embedded ferrous material. For example, the plastic target wheel may be one of the plastic target wheels 14 , 14 ′ having the gear teeth 24 , 24 ′, respectively. The plastic target wheel is then removed from the injection molding form in step 108 .
In step 110 an outer portion of each gear tooth is removed to expose the ferrous material and create a suitable target for a speed sensor. For example, the outer portion of the gear teeth may be ground through turning or grinding to expose the ferrous material. In alternative embodiments the ferrous material is included in an amount that will suitably alter a sensor's magnetic field through an outer plastic layer of the gear teeth, and step 110 may be omitted. It should be appreciated that other considerations such as packaging space may influence whether step 110 is to be carried out.
Accordingly, the present invention provides a simple yet effective target wheel that has low complexity, is low cost, and is lightweight.
The description of the disclosure is merely exemplary in nature and variations that do not depart from the gist of the disclosure are intended to be within the scope of the disclosure. Such variations are not to be regarded as a departure from the spirit and scope of the disclosure. | A speed target wheel includes an annular body portion and a plurality of gear teeth. The annular body portion consists of a plastic material and the plurality of gear teeth project from the annular body portion. Each of the plurality of gear teeth includes a base portion adjacent the annular body portion and a tip portion, where the base portion is integrally formed with the annular body portion and substantially comprises the plastic material, and where the tip portion includes a ferrous region integrally encompassed by the plastic material. | 6 |
BACKGROUND OF THE INVENTION
[0001] The present invention relates to a closure system and in particular to closure systems associated with vehicles such as land vehicles, aircraft and marine vehicles. One specific use of the invention would be in automobiles.
[0002] Automobiles are known whereby doors of such automobiles include windows which can be power opened and power closed. When a window is being power closed, it is possible for parts of people or children to be get trapped in between the window and window surround. In order for such windows to function within legal and other requirements, it is necessary to avoid applying more than a certain, predetermined maximum force to an arm, finger or other part of the body when that part of the body interferes with the normal closure of the window. Equally, it is necessary to ensure that a sufficient force is available to fully close the window into its seals. To this end, the relevant specifications allow for the limited force to be exceeding once the opening is smaller than would admit entry of any part of the body. Thus in known contact type anti-trap (anti-squeeze) systems a switch, typically within the door seal, is closed when a body part is trapped, and this triggers a decision within a control unit to stop or reverse the closing motion, and thereby release the body part.
[0003] Other known contact type anti-squeeze systems rely on an inference trap force from a parameter measurable at the motor such as change in motor speeds, change in motor current or change in output torque, all of which are related to the forces applied to the closure ie the output force of the actuator assembly.
[0004] However, due to rough roads or other terrain over which the vehicle may be travelling, primarily vertical accelerations are imposed on the vehicle. These vertical accelerations are applied to the window glass as to any other part of the vehicle and are reacted through the window regulator as variations in closure force. Under some circumstances these variations may produce forces on the window glass which resemble the forces produced when body parts are trapped. Under such circumstances the control unit will incorrectly reopen the window then this is unnecessary. Alternatively when a body part is being trapped, accelerations on the window glass due to rough terrain may reduce the apparent trapping force to below the predetermined level where upon closure will continue and further trap a body part.
[0005] Thus situations arise which are inconvenient and/or distracting and are potentially dangerous for the occupants of the vehicle.
SUMMARY OF THE INVENTION
[0006] An object of the present invention is to provide an improved form of closure system.
[0007] Thus according to the present invention there is provided a closure system including a closure moveable for substantially closing an aperture in use, and an actuator for at least closing the closure, the actuator being mounted by mounting means, the mounting means including one or more measurements cells for measuring, in use, parameters of the closure system, in use the closure system being subjected to accelerations and being arranged such that it is possible to at least partially distinguish forces applied to the closure by the actuator from acceleration forces applied to the closure as a result of the accelerations of the closure system by consideration of the measured parameters.
[0008] Advantageously this provides for a system wherein mounting means of an actuator are able to fulfil a triple function, namely mounting of the actuator and also measurement of forces applied to the closure by the actuator and also measurement of forces applied to the closure as a result of the accelerations of the closure system.
[0009] Furthermore the applicant is the first to realize that the closure and the actuator are subjected to substantially the same accelerations and thus the actuator can be used for determining the acceleration forces on the closure. Once the acceleration forces on the closure have been determined then it is possible to subtract these from output force of the actuator to more accurately determine true trap forces.
[0010] According to a further aspect of the present invention there is provided an aperture motor assembly for at least closing an aperture, the motor assembly including measurement cells being arranged such that in use it is possible to at least partially distinguish forces applied to the associated aperture closure by the actuator from accelerations forces applied to the associated aperture closure as a result of accelerations of the aperture closure and motor assembly by consideration of the output from the measurement cells.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] The invention will now be described by way of example only, with reference the accompanying drawings in which:
[0012] [0012]FIG. 1 is a side view of a vehicle including closure system according to the present invention;
[0013] [0013]FIG. 2 is a cross section view of the window motor and gearbox of FIG. 1 and
[0014] [0014]FIG. 3 is a further view of FIG. 2.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0015] With reference to FIG. 1 there is shown a vehicle 10 having a door 12 with a window aperture 14 . An aperture closure in the form of a window glass 16 is moveable vertically to open and close the window aperture 14 . A window regulator shown generally as 18 includes a window motor 20 and a gearbox 22 .
[0016] The motor 20 and gearbox 22 are mounted via mounting means, in this case in the form of first mount 24 and second mount 26 . First and second mounts 24 and 26 include load cells in this case shear load cells C 1 and C 2 each forming the load reaction path between the motor and the vehicle door, and between them constrain the motor within the door.
[0017] The shear load cells C 1 and C 2 are positioned at distance 2R from each other and the geometrical position of the center-of-gravity CG of the motor/gearbox is also known.
[0018] Consideration of FIG. 2 shows that the shear load cells C 1 and C 2 have output levels S 1 and S 2 .
[0019] An output torque T from the motor 20 acts clockwise around the motor output shaft when the window is being closed and, with the vehicle 10 stationary, is a function of a output force f.
[0020] The weight of the gearbox and window motor acts through the center-of-gravity CG. With the vehicle 10 stationary the force M at CG is equivalent to the combined weight of the motor 20 and gearbox 22 . However, with the vehicle moving over rough terrain the force M will vary. It should be noted that CG is located horizontally by distance x from shear load cell C 1 and vertically from shear load cell C 1 by distance z.
[0021] Consideration of FIG. 3 shows that the forces S 1 and S 2 can be resolved in the x and y directions and become S 1 x, S 1 z, S 2 x and S 2 z. The output torque T of the motor can be considered to be a tangential force Ft acting at a radius r equivalent to the pitch circle diameter of a drum or pinion and, for convenience, this has been shown to be parallel to the z axis.
[0022] Note that the analysis below is more complicated where the sensors and output shaft are not in line, and/or the forces act at some other angle, but it may demonstrated that the same principles apply.
[0023] Consideration of the above shows that several equations can be written, which express the situation at steady state ie with the vehicle 10 stationary and the window closing at a constant speed.
[0024] Given that we do not know the directions of S 1 and S 2 merely their magnitudes then, by pythagoras:
S 1 x 2 +S 1 z 2 S 1 2 and S 2 x 2 +S 2 x 2 =S 2 2
[0025] Since we have conveniently defined Ft parallel to z axis and M acting vertically downwards, also parallel to the z axis then,
Ftx=0 and Ftz=Ft, and furthermore
Fmx=0 and Fmz=M
[0026] Resolving in x and z we have the summations:
∫ x= 0, ∫ z= 0, thus
S 1 x+S 2 x= 0, S 1 z+S 2 z=Ft−M
[0027] And taking moments about S 1
S 2 z· 2 R+FT ( R+r )= M·x
[0028] Collecting Terms
S 2 z=Ft ( R+r )/2· R−M·x/ 2· R
[0029] of which R, r & x are all known and constant for a given application.
S 2 z=Ft·k 1− M·k 2
[0030] Where the constants k 1 =(R+r)/ 2 ·R & k 2 =x/ 2 ·R; thus
S 1 z=Ft−M−S 2 z
S 1 z=Ft−M−Ft ( R+r )/2· R−M·x/ 2· R
[0031] Collecting Terms
S 1 x=Ft−Ft ( R+r )/2· R−M−M·x/ 2· r
S 1 z=Ft (1( R+r )/2· R )− M ( M 1− x/ 2· R )
But k 1=( R+r )/2· r & K 2= x/ 2· R, so
S 1 z=Ft (1− k 1)− M (1− k 2)
[0032] following which
[0033] Thus S 2 =Ft·k1−M·k2, and
S 1=Ft(1− k 1)− M (1− k 2)
[0034] S 1 and S 2 from the output from the shear load cell C 1 and C 2 , k1 and k2 being constant, we now have two equations and two unknowns (Ft and M) and therefore can solve for Ft and M.
[0035] This solution allows comparison of the motor/gearbox effective weight M and the known pre-measured value of the motor/gearbox weight. This comparison gives an instantaneous value for the vertical g-forces applied to the window motor and therefore the adjacent window glass and permits greater discrimination of the system loads resulting from the vehicle movement from those associated with a trapped object or body part.
[0036] Thus the above system, by comparing the output S 1 and S 2 from the shear load cell C 1 and C 2 , the proportion of the measured output due to vertical acceleration and that due to an object trapped may be distinguished arithmetically and thus a better definition of actual trap force (as opposed to apparent trap force) maybe obtained. As such it is possible to largely eliminate interference with the true trap force signal caused by vibration and/or accelerations with a large vertical component. The present invention achieves this in a particular cost effective manner as a minimum of components are required since the shear load cells C 1 and C 2 provide both the function of mounting the motor and also of measuring the parameters which can be used to determine true trap force from apparent trap force.
[0037] As a result of improved sensitivity of the system to objects being trapped, lower force thresholds may be specified and therefore more rapid reaction may be obtained both of which leads to a reduction in the overall trap force experienced by the person or object.
[0038] The system also reduces the likelihood of false trap signals and hence false reopening of the window, thus reducing the possibility of distraction and annoyance to occupants of the vehicle.
[0039] Once the window is virtually closed such that any gap between the window glass and window aperture is sufficiently small to not allow entry of a small body part such as a finger, then the anti-squeeze requirement is no longer necessary. Thus when the window glass reaches such a position this position can be indicated by a proximity sensor, micro switch or the like which would indicate to control means of the window that anti-squeeze is no longer required for the final closing of the window.
[0040] It is envisaged that the present invention could be used in a variety of applications, such as automotive windows and other partitions moving in a primarily vertical direction. However, the principles outlined above would be applicable to other types of closure where the motor may be so mounted as to be subject to the disturbing forces in the same manner as the closure being operated by that motor. Further applications include vehicular sun roofs, transverse and longitudinal sliding doors as typically used for corridor and compartment closures in trains and aircrafts, and other types of sliding partition on ships and other marine vehicles.
[0041] The foregoing description is only exemplary of the principles of the invention. Many modifications and variations of the present invention are possible in light of the above teachings. The preferred embodiments of this invention have been disclosed, however, so that one of ordinary skill in the art would recognize that certain modifications would come within the scope of this invention. It is, therefore, to be understood that within the scope of the appended claims, the invention may be practiced otherwise than as specially described. For that reason the following claims should be studied to determine the true scope and content of this invention. | A closure system including a closure moveable for substantially closing an aperture in use, and an actuator for at least closing the closure, the actuator being mounted by mounting means, the mounting means including one or more measurement cells for measuring, in use, parameters of the closure systems, in use the system being subjected to movement and being arranged such that it is possible to at least partially distinguish trap forces applied to the closure from acceleration forces applied to the closure as a result of the movement of the closure system by consideration of the measured parameters. | 4 |
FIELD OF THE INVENTION
The present invention relates to a device for trapping and dispatching small animals such as rats and mice through electrocution. In particular, the invention relates to a trap which can operate without being attended to.
DESCRIPTION OF PRIOR ART
The extermination of noxious animals is a well-known problem. In a common approach the noxious animals are captured and killed in a trap. Several types of traps have been developed. The present invention deals with a trap, wherein the executing means is electrocution. In an electrocuting trap the animal is killed by an electrical current that is drawn through the body of the captured animal. Several types of electrocution traps have already been described, for example in the patents U.S. Pat. Nos. 1,038,902; 5,918,409; 5,949,636 and in the application FR 2 758 435-A1. In such traps a bait or lure is placed inside a housing with one or more entrances. Between the entrance(s) and the bait a configuration of electrodes is present. The inside of the trap is designed in such a way that, if an animal tries to reach the bait, the animal inevitably touches the electrodes and thereby gets electrocuted.
None of the previously described traps, however, deal with the situation where regular control of the traps is inconvenient. Such situations can be encountered if the trap is located at a place, which is difficult to access. Or, if a large number of traps are in operation, e.g. in a city-extermination program, where a network of traps are placed in a sewer system. Surveillance of such a trap system requires considerable efforts, if all traps have to be monitored by subsequently checking all traps one at a time.
DESCRIPTION OF THE INVENTION
In a first embodiment, the above mentioned problem has been solved by the present invention by providing an electrically powered animal trap, which comprises
a set of electrodes for electrocution of the animal, and means for communicating a surveillance signal between the trap and an external surveillance unit.
Due to the means for communicating a surveillance signal between a trap and an external unit, the keeper of the trap may know the condition of the trap without direct inspection of the trap. The trap may thus be left unattended for a long period time, where the trap keeper can rest assure, that the trap is fully operational.
The trap may comprise a bottom section with an upwardly extending sidewall, a top section, and at least one entrance. The entrance may be either in a sidewall, in the top section of the trap, in the bottom section of the trap, or anywhere else. Upon entering the trap, the animal enters a chamber, where a bait or lure may be placed in the opposite side of the chamber. The set of electrodes may comprise at least two electrodes, e.g. placed between the entrance and the end section where bait can be placed. The bait may be a liquid dripping in a controlled way, which ensures a continuous supply of strong scent, it may be in the form of dry pills or tablets, it may be food, or it may be a scent means. A bait storage arrangement may be provided, this may enable automatically feeding the bait to a trough, and furthermore control the flow of the bait from a storage to ensure optimal dosing. The surface of the electrodes may be rough. e.g. by adhering metal or plastic shavings to a metal plate in any conventional way, e.g. plastic composites incorporating metal conductive wires or shavings. Another possibility for making the electrode surfaces rough, is by using powder metallurgy. However, smooth surfaces of the electrodes may also be provided. In case three electrodes are used, the electrodes may be interconnected in a way such that a first of the electrodes is connected to a second of the electrodes and wherein a third of the electrodes is electrically insulated from the first and second electrodes. A small voltage up to 4,5 V DC may be maintained between the two first electrodes and the third. The source may be a small accumulator, such as a 12 V motorcycle battery. An electronic circuit (a sensor circuit) may be adapted to detect a leak current between the first and the third electrode by detecting the presence of a finite resistance. This will happen when an animal is touching electrode 1 , at the same time as it is touching electrode 3 . A high-voltage potential difference between the first and the third electrode should then be generated by an additional “power electronics”, which can be incorporated with the sensor circuit. The result is that the animal is electrocuted. The high-voltage potential may be in the form of a continuous voltage maintained for a predefined time, or it may be in the form of a series of pulses. The use of pulses may be advantageous, as the animal may be killed faster and less painfully. These pulses may have the form of steps, where each step comprises different voltages kept for different time periods. The pulses may also be in the form of a sinusoidal wave, or it may be a series of short pulses. The electronic circuit may be made in a versatile way where these aspects can be adjusted electronically. Alternatively, only two electrodes may be used.
The trap may comprise additional or different means for detecting the presence of an animal by equipping the trap with a weight sensitive detector, a motion sensitive detector, which may be achieved by using one or more infrared sensors, or a lever arm. These means may be added in order to increase the certainty that an animal is present in the trap, before the high-voltage potential is generated, or they may be used as alternative means for detecting the presence of an animal.
The trap may be equipped with an exit for removing the electrocuted animal into a receptacle. This receptacle may be an open receptacle as a sewer or a small stream of water into which the dead animal may be dumped by e.g. using a trapdoor in the bottom of the trap. To accommodate a trap in such a situation, the trap may be equipped with lifting means to lift up the trap. The lifting means may be one or more legs that are adjustable in length, for example telescopic legs, i.e. legs where a single or a series of thinner legs are sliding inside a thicker leg, and where a specific length can be maintained by a fixing means. The adjustment of the length of these legs can be facilitated by using pressurized gas in a similar manner as with office chairs. The receptacle may likewise be a sealed container on top of which the trap is fastened. The container may be equipped with a bag in which the dead animals are collected. A bag will ensure easy and hygienic emptying of the trap as no physical contact with the dead animals is needed. The receptacle may contain a chemical bath for dissolving the animal.
The trap is fully automatic and controlled by the electronic circuit. The exit can be actuated either electrically, hydraulically, pneumatically, mechanically or by any combination of these. For example a trapdoor where the locking-unlocking is an electromagnetic tap which unlocks the trapdoor when the electrocution has finished. The trapdoor can be fastened to the trap by a pivotal hinge at one side such that the door opens upon the weight of the dead animal, and tips back due to a counter weight. In another design the trapdoor is also attached at one side with a pivotal hinge, but in this case the opening and closing is controlled by a motor which unrolls and rolls up a piece of string. It is also possible to place the hinges at opposite sides of the trapdoor, such that the trapdoor tips around an axis perpendicular to the axis around which, the trapdoor tip when the hinges are places in the same side of the trapdoor.
As the trap may be raised above the surroundings, an entrance ramp may be needed. The ramp may be constructed in wood. But it may likewise be constructed in plastic, stainless steal, nickel or any suitable material.
As the inside of an electrocution trap may be dangerous to touch, a tube or a flexible hose may be mounted in front of the trap entrance. By using a bent tube (or a flexible hose), e.g. an s-form, an elbow form or a zigzag form, a child will not be able to get its arm inside the trap. A trap which has such a mount placed in front of the entrance is therefore a lot safer to place in areas where children may play than other types of traps. The entrance may also be equipped with a clipping means, thereby enabling to clip on and use any suitable material as entrance.
A battery can only supply a limited number of electrocutions before it needs to be recharged. The trap may therefore be equipped with a power adapter that allows connection directly to a power grid. Some traps may be placed at locations where it is not possible to directly connect the trap to a power grid. In this case the trap can be equipped with a chargeable battery.
The trap may be able to stand flooding or high water levels if, e.g., it is located in a sewer. This may be achieved by embedding the electronics in a waterproof housing, and furthermore by incorporating a water detector that may transmit an electronic signal, e.g. in the case the water level rises above a predetermined level. The electronic circuit may be adapted to react in response to a signal from the water detector, by disabling the generation of the high-voltage potential. The water detector may comprise a timer detecting at predetermined time interval whether or not high voltage generation may be performed, or whether or not it may be safe to switch on the electronics.
The electronic circuit could comprise means for storing an identification code for the trap, and/or information relating to the number of captured animals, the remains of the bait, and the battery condition. A display could be included in the electronic circuit, such that the above mentioned trap information may easily be read-out. The electronic circuit could furthermore comprise means for sending out a wireless electromagnetic surveillance signal that may be received and read by an external unit. The signal may comprise the above mention features and may only send out upon receiving a request signal from the external unit, thereby avoiding draining the battery. A surveillance signal may also automatically be sent out in the case of a capture, in the case of low battery power or in the case of loss of bait. The surveillance signal may be any electromagnetic signal, such as a radio-signal, or a signal around 2,4 GHz which is the Bluetooth standard frequency, or a signal in the low frequency domain, such as few hundred KHz. The trap may additionally comprise means for determining the geographical position of the trap. This may be achieved by incorporation a global positioning system devise (GPS), a mobile positioning system device (MPS), such technology has been demonstrated by the Swedish corporation Ericsson, or a Nordic Mobile Telephone (NMT) device. The surveillance signal can therefore further comprise the position of the trap. The electronic circuit may also be equipped with a means for receiving a command signal send out by the external unit. This would be useful if, for example, the trap is further equipped with a size adjustable entrance opening.
Above, only the situation of a single trap is described. An ensemble of traps may be monitored by a software program adapted to store information on the identity code, the position, etc., of the individual traps in the network. The software should collect information about the number of captures, the condition of the bait, and the current power on the battery. A trap keeper could then fast obtain an overview of the traps that are needed to be tended to.
BRIEF DESCRIPTION OF THE DRAWINGS
In the following, a preferred embodiment of the invention will be described with reference to the drawing in which:
FIG. 1A and 1B are 3D cut of preferred embodiments of the invention,
FIG. 2 is an example of a voltage diagram,
FIG. 3A-3C are preferred embodiments of a trapdoor,
FIG. 4 illustrates the invention in connection with a closed receptacle, and
FIG. 5 illustrates the invention mounted in a sewer.
DETAILED DESCRIPTION OF THE FIGS
In FIG. 1A , a 3D cut of a preferred embodiment of the present invention is presented. The trapping chamber is inside a housing which comprises sidewalls 1 , a top 2 and a bottom section 3 , 4 . The access to the trapping chamber is an opening in one end of the trap housing. The entrance is not shown, but it could be an opening in a wall adjacent to the sidewall 14 . The bottom section 3 , 4 comprises two parts, one part 3 which is fixed with respect to the housing as a whole, and another part which is movable. The movable part 4 constitutes an exit, here illustrated as a trapdoor that opens in a downward direction. A set of electrodes comprising a first electrode 5 , a second electrode 6 and a third electrode 7 , are placed sequentially between the entrance and the section where the bait 8 , 9 and 16 is placed. From the bait reservoir 9 , a scent-liquid is dripping into a small bowl 8 . The bait reservoir may be re-filled from outside the trap 16 , as the reservoir protrudes through the top section of the trap. The power source of the trap is a 12 V DC battery 10 , placed on top of the trap. An electronic circuits 11 is also placed on top of the trap. The electronic circuit includes a means for communicating a surveillance signal. The surveillance signal is transmitted through the antenna 15 . The opening and closing of the trapdoor is actuated by a small motor 12 adapted to unroll and roll up a string in order to open and close the trapdoor.
The electronic circuit 11 comprises:
1. an electronic-print card with a microprocessor, a sensor circuit, a “power electronic” to drive the motor and the high voltage generator, 2. a motor to remove the animal from the trap chamber, 3. a display, and 4. a transmission system to remote read-out.
The sensor circuit is set to detect a leak current between the first electrode 5 and the third electrode 7 , alternatively, between the second electrode 6 and the third electrode 7 , by detecting a finite resistance between the electrodes. It can be adjusted electronically to register a resistance between 2 kΩ and 500 kΩ. The electrodes are kept at a potential of maximal 4.5 V DC between captures. In case of a detection of a finite resistance between the first electrode 5 (or the second electrode 6 ) and 7 , an electrocuting high-voltage potential is generated between the same electrodes. The duration of the high-voltage potential can be adjusted electronically from 100 ms and up to permanent, with an output voltage between 500 V and 4 kV, and a transmitted power between 100 mW and 25 W. The potential change uses that the inductivity in the transformer when the period for the high voltage transformer is short. The duration is controlled by the microprocessor. The power in the electrocuting-process is changed by changing the duty-cycle of the voltage transformer, the total power admitted is thereby controlled. Also the electrocuting voltage can be varied, one example is given in FIG. 2 . The details of the variation in the voltage difference can be further elaborated upon using experience gained in experiments. The power-electronics control the motor, both with respect to speed, and with respect to the time the exit remains open. A circuit can be added which register when the motor stalls. A display shows the number of electrocutions, the remaining amount of the bait as well as the current voltage on the accumulator. The transmission system should be of the wire-loop principle, as this does not require broadcasting approval. Furthermore, this type of system works at low frequencies and can be used to transmit through earth and water.
In FIG. 1B , the trap as described in connection with FIG. 1A is slightly modified. Here the bait reservoir 9 and a the small bowl 8 are positioned in the central region of the trap. The presence of an animal is detected using an infrared sensor 100 , and only two electrocuting electrodes 101 , 102 are used.
FIG. 2 gives an example of the voltage difference between first electrode 5 and the third electrode 7 , or between electrode one 101 and two 102 , versus time during the electrocuting process. At t=0 the electrocuting voltage difference is generated. At t=t 1 the voltage difference drops to a predefined level which is kept until t=t 2 where the voltage difference is raised until a new pre-defined level. At t=t end the voltage difference is set to zero.
FIG. 3A shows a second embodiment of the trapdoor 4 , where instead of using a motor 12 and a string 13 , the actuation of the trapdoor is an electromagnetic switch 30 adapted to open upon a signal from the electronic circuit 11 . Due to the weight of the electrocuted animal, the trapdoor opens by pivoting around a pivot tap 31 , and closes after release of the animal due to counter weights, here exemplified by a threaded bolt 33 and a nut 32 .
In FIG. 3B and 3C a third embodiment of the trapdoor is shown. Here a solenoid 202 Is used to open and close the trapdoor. The solenoid may be fixed to the trap using fixation means 200 and 201 . By activating the solenoid, rod 203 is pulled into the solenoid, which through a mechanical coupling to the trapdoor, opens the trap door, as shown in FIG. 3C .
Using a solenoid may e.g. increase the control of the trapdoor. For example it may be possible to shake the trapdoor to make sure the animal has fallen off, or to clear the trapdoor from debris or dirt on the electrodes or the trapdoor in general.
FIG. 4 and 5 show two examples of trap set-ups. In both Figs. the trap 20 is raised above the surroundings, and access to the trap chamber is ensured by a ramp 21 . In FIG. 2 the trap is placed on top of a receptacle 22 , into which the animals are dumped after the electrocution. Where FIG. 4 present a trap set-up that can be used in many different locations, e.g. a store-house, a barn or a field, FIG. 5 envision a special case where the trap is placed directly above a sewer stream. In this situation the sewer it-self is used as a receptacle where the animals are dumped directly into after electrocution. The trap is fastened in the sewer by using length adjustable legs 23 . In FIG. 5 the trap is positioned along the sewer, however, the trap may also be positioned so that it bridges the water stream, i.e. positioned rotated 90 degrees with respect to the one shown. | An electrically powered rodent trap which includes a surveillance system for remote surveillance of the trap so that the trap may be operated without being attended to. A rodent which enters into the trap is killed by means of electrocution electrodes. The dead rodent is automatically dispatched from the trap, e.g. by a trapdoor, into a container or reservoir beneath the trap. The number of electrocutions and possible other data is stored by an electronic system incorporated in the trap and a signal is sent out, either by request from an external unit, or automatically to an external unit. A city rodent exterminator is capable of monitoring the status of the trap from an office location and thereby effectively tend to the trap or to a series of traps. | 0 |
CROSS REFERENCE TO RELATED APPLICATIONS
This application is a Divisional patent application of U.S. application Ser. No. 10/780,463, filed on Feb. 17, 2004, now U.S. Pat. No. 7,588,728, issued on Sep. 15, 2009, the entire contents of which are incorporated by reference herein.
BACKGROUND OF THE INVENTION
Test plates for chemical or biochemical analyses, which contain a plurality of individual wells or reaction chambers, are well-known laboratory tools. Such devices have been employed for a broad variety of purposes and assays, and are illustrated in U.S. Pat. Nos. 4,734,192 and 5,009,780, for example. Microporous membrane filters and filtration devices containing the same have become particularly useful with many of the recently developed cell and tissue culture techniques and assays, especially in the fields of bacteriology and immunology. Multiwell plates, used in assays, often utilize a vacuum applied to the underside of the membrane as the driving force to generate fluid flow through the membrane.
The microplate has been used as a convenient format for plate processing such as pipetting, washing, shaking, detecting, storing, etc. A variety of assays have been successfully formatted using multiwell filter plates with vacuum driven follow-through. Applications range from Cell Based assays, genomics and proteomic sample prep to immuno-assays.
An example of a protein digestion sample process may include the following steps:
1. Deposit the protein sample in the wells with the digestion enzymes.
2. Bind or capture the digested protein in or on the filter structure.
3. A series of sample washes where the solutions are transferred to waste by vacuum.
4. Solvent elution to recover the concentrated sample.
Another filter plate application used for a Genomic Sequencing Reaction Clean-up may include the following steps:
1. Deposit the sample into the wells and concentrate product onto the membrane surface by vacuum filtration to waste.
2. A series of sample washes where the solutions are transferred to waste by vacuum. Repeated and then filter to dryness.
3. Re-suspend the sample on the membrane and aspirate off the re-suspended sample from the membrane surface.
Washing to waste is easily accomplished with virtually any of the conventional manifolds available. During a wash step, a relatively large volume (greater than 50 .mu.l) of aqueous solution is added to the wells and drawn to waste. The orientation of the plate is not critical when adding a large volume of liquid, as long as the transfer pipette or other device is able to access the well opening. However with the Protein Digestion example, the elution volumes are relatively small (less than 15 .mu.l) and can be as low as about 1 .mu.l. This small volume needs to be deposited directly on the filter structure in the well to insure the solvent is drawn through the structure for complete elution of the sample. With the other example, Sequencing Reaction Clean-up, the final concentrated sample is between 10-20 .mu.l and must be aspirated off the membrane without damaging the membrane surface.
Many of these and other protocols require the addition of small accurate liquid volumes. When using filter bottom plates the performance benefit is achieved because of the follow-through nature of the filter. To achieve flow through the filter a pressure differential is applied. When using automated equipment, vacuum filtration is the preferred method because of its convenience and safety. To filter by vacuum, many manufacturers provide a vacuum manifold for their products and equipment. Still, accurate liquid transfer is not possible on the deck of a conventional liquid handler, because the position of the plate in the Z-direction can vary during use. Indeed, all of the standard manifolds available today use a compressible gasket material to seal the filter plate, and during the evacuation of the vacuum chamber in the manifold, the plate moves as the gasket is compressed. The amount of plate movement varies, depending in part upon the durometer of the gasket used and the vacuum pressure that is applied. The amount of movement is too great or variable to be able to program a liquid handling robot to account for the movement, making successful, reproducible automated transfer difficult or impossible. Similar problems arise with the Sequencing clean-up where the small volume is aspirated off the surface of the membrane. If the position of the membrane varies then it is not possible to program the automated equipment to aspirate off the surface of the membrane without potentially damaging the membrane surface.
Additionally, to insure quantitative transfer of filtrate from a 384-well filter plate into a collection plate, the spouts must be as close to the collection plate openings as possible. The available manifolds have a gasket sealing to the underside of the filter plate, and thus the only way to use these manifolds to achieve quality transfers is to have the spouts extend below the plate flange and into the wells of the collection plate. However, in such a design, the spouts are exposed and are thus prone to damage and/or contamination.
It is therefore an object of the present invention to provide a vacuum manifold assembly that is readily adapted to automation protocols.
It is another object of the present invention to provide a vacuum manifold assembly that fixes the position of a sample-processing device, such as a multiwell plate, regardless of the vacuum applied.
It is a further object of the present invention to provide a vacuum manifold assembly with features that enable quantitative filtrate transfer to a collection well when used with multiwell plates with dense arrays of wells.
It is another object of the present invention to provide a vacuum manifold assembly that enables direct transfer on an analytical device such as and MALDI target.
It is still another object of the present invention to provide a vacuum manifold assembly that is modular and adaptable to a variety of applications.
SUMMARY OF THE INVENTION
The problems of the prior art have been overcome by the present invention, which provides a laboratory device design particularly for a multiwell plate format that includes a manifold wherein the position of the plate is not a function of gasket compression or vacuum rate applied. The design also can be used with a single well device, particularly when small volume liquid processing applies. In one embodiment of the present invention, the device has a modular design, wherein removable inserts with different functionalities can be positioned between a base component and a collar component. The particular inserts chosen depend on the desired sample preparation or assay to be carried out. The inserts are stacked and are positioned between the base and collar as a unit, so variation in height of the stack within the manifold is as a unit and is constant; i.e., there is no relative movement of one insert with respect to another insert, even upon evacuation of the vacuum chamber. Therefore, the automated liquid handlers can be programmed to position the pipette tip in close proximity to the well bottom or filter surface for small volume dispensing or aspirating.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an exploded view of a manifold assembly in accordance with an embodiment of the present invention;
FIG. 2 is a perspective view of the manifold assembly shown in an assembled condition;
FIG. 3 is an exploded view of a manifold assembly in accordance with an alternative embodiment of the present invention;
FIGS. 4A and 4B are exploded views of a manifold assembly in accordance with another embodiment of the present invention;
FIG. 5 is an exploded view of a multiwell plate sealed to the top of the manifold assembly in accordance with an embodiment of the present invention;
FIG. 6 is a perspective view of the assembly of FIG. 5 ;
FIG. 7 is a cross-sectional view of the manifold assembly with a bottom gasket in accordance with an embodiment of the present invention;
FIG. 8 is a cross-sectional view of Detail A of FIG. 7 ;
FIG. 9 is a cross-sectional view of the manifold assembly with a unitary common gasket used for sealing;
FIG. 10 is a cross-sectional view of the manifold assembly with a unitary flexible gasket used for sealing;
FIG. 11 is a cross-sectional view of the manifold assembly for three plates;
FIG. 12 is a cross-sectional view of the manifold assembly utilizing a deep well filter plate and a regular collection plate; and
FIG. 13 is a cross-sectional view of the manifold assembly utilizing a deep well filter plate and collection plate.
FIG. 14 is an exploded view of a manifold assembly in accordance with another embodiment of the present invention.
FIG. 15 is a cross-sectional view of a manifold assembly in accordance with a further embodiment of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
There are two common components in the vacuum manifold assembly in accordance with the present invention, regardless of the application. With reference to FIG. 1 , the common components are a base 12 and a collar 14 , together sized and configured to contain sample-processing components. The base 12 optionally includes a port 13 for communication with a driving force, such as a source of vacuum, preferably a vacuum pump. Alternatively, the port 13 maybe located in a wall of the collar as shown in FIG. 14 . The base 12 also includes a bottom 12 A and one or more sidewalls upstanding therefrom. In the rectangular embodiment shown, there are four connecting sidewalls, namely, opposite sidewalls 12 B and 12 C, and opposite sidewalls 12 D and 12 E. The base includes an outer peripheral flange 4 that in combination with an inner peripheral portion of the sidewalls forms a peripheral groove 6 ( FIG. 8 ) that receives gasket 5 . Preferably the gasket 5 has a lower peripheral portion 5 A that seats in the groove 6 and a top peripheral portion 5 B that extends above the groove 6 . The upper portion 5 B is skewed outwardly so that when the lower portion 5 A of the gasket is in place in the groove 6 , the upper portion 5 B it is aligned or substantially aligned with the outer surface of the side walls 12 B, 12 C, 12 D and 12 E. The gasket 5 thus creates a seal between the base 12 and the component in contact with the gasket 5 , such as the collar 14 , as discussed in greater detail below. Optionally, and as shown in FIG. 1 , one can have of one or more alignment tabs 17 that arise up from the base, preferably at one or more of the intersections of the adjacent sidewalls. The one or more tabs 17 are used to help position the sample processing units (filter plates, MALDI target supports, collection plates, spacers and/or inserts, described below in more detail) into the base 12 and to align the collar 14 to the base 12 . Other configurations are within the scope of the invention, provided a seal is created.
In the embodiment shown, collar 14 also has four lateral walls, namely, opposite walls 14 B, 14 C and opposite walls 14 D, 14 E. The lateral walls must extend downwardly (and/or the side walls of the base 12 must extend upwardly) a distance sufficient to accommodate the components that are positioned between the collar 14 and the base 12 . The vertical length of these lateral walls (and/or the side walls) thus can vary depending upon the application. A skirt 15 preferably is formed along the bottom periphery of the lateral walls such that the skirt 15 positions over the peripheral portion 4 of the base 12 in sealing relationship when in the assembled condition, as seen in FIG. 2 . A gasket 75 is attached to the inner, top surface of the collar 14 around the top opening and is designed to seal against the top surface of a component disposed against the collar, as discussed in greater detail below. The gasket 75 preferably includes a peripheral slot 77 that mates with a corresponding inner peripheral rib 79 in the collar 14 , shown in FIG. 7 . A plurality of rectangular steps 74 may also be provided in the gasket 75 , shown in FIG. 2 , to mate with support insert 37 shown in FIG. 5 .
It will be understood by those skilled in the art that the invention is not limited to any particular sealing means. For example, instead of separate gaskets that seal the collar and the base, a single unitary gasket 55 or flexible unitary gasket 55 ′ could be used, such as is shown in FIGS. 9 and 10 .
It also will be understood by those skilled in the art that the invention is not limited to any particular sample processing device; devices that enable filtration, collection, digestion of protein by enzymes, wash steps, solvent elution, MALDI TOF, sequencing, PCR clean-up, cell growth, cell lysis, DNA or RNA capture, assaying, etc. can be used in the present invention.
Those skilled in the art will understand that the port for the driving force such as a vacuum port could be in the base 12 as in FIG. 1 or the collar 14 as in FIG. 14 . When the vacuum is used in the collar 14 , a separate and distinct base becomes an optional, although preferred element of the invention. As shown in FIG. 15 , with the port 13 in the collar 14 one may if so desired use any relatively flat surface-such as a bench top, the floor or a wall as the base 12 and the seal is formed by the collar and the first seal between the collar and base (the surface against which it is placed).
The present invention can be used with a variety of plates and other components that are generally used in such plate systems. These include but are not limited to microporous filter plates, ultrafiltration filter plates, chromatographic plates (either containing chromatography media or having a monolithic structure containing such media cast in place in a portion of the plate), cell harvester plates, cell growth plates such as Caco 2 cell growth plates, cell lysis plates, DNA or RNA or plasmid capture plates, collections plates with single or multiple wells, MALDI target trays and/or MALDI targets and the like.
A single plate may be used with the present manifold if desired, either within the collar or on top of the collar (as explained in more detail below). Generally, two or more plates can be used together by stacking them in the proper arrangement such as a microporous filter plate on top of a ultrafilter filtration plate that is on top of collection plate, a microporous filter plate on top of a collection plate, a ultrafilter filtration plate on top of collection plate, a filter plate on top of a chromatographic plate or a DNA or RNA or plasmid capture plate, or the like.
Additionally, spacers may be placed between the plates or under the plate(s) if desired or required for a particular application. Likewise, flow director plates, separate underdrain plates or spout plates between adjacent plates or wicks such as are shown in our co-pending application U.S. Ser. No. 09/565,963, filed May 20, 2000, may also be used in the present invention to direct the flow of fluid in a particular manner. A variety of adaptor plates, half or quarter plates with different configurations and/or characteristics may also be used in the present invention.
Depending upon the application, generally the sample processing components are molded parts and are solvent compatible. The sample processing devices include single well and multiwell devices. Metals, polyolefins and filled nylon are suitable materials of construction. Rarely used components can be machined. In the embodiment shown in FIGS. 1 and 7 , the sample processing devices positioned between the base 12 and collar 14 are a filter plate 20 and a collection plate 22 , both preferably being made of polyethylene, and thus the length of the lateral walls of collar 14 (and/or the side walls of the base 12 ) is made sufficient to accommodate these components when assembled to the base 12 . In the embodiment shown in FIG. 11 , the sample processing devices positioned between the base 12 and collar 14 are filter plates 20 and 20 A and a collection plate 22 . The filter plates 20 and 20 A, and the collection plate 22 are configured for proper stacking and alignment as is known in the art.
The filter plates 20 and 20 A includes a plurality of wells 21 and 21 A, preferably arranged in an ordered two-dimensional array. Although a 96-well plate array is illustrated, those skilled in the art will appreciate that the number of wells is not limited to 96; standard formats with 384 or fewer or more wells are within the scope of the present invention. The wells are preferably cylindrical with fluid-impermeable walls, and have a width and depth according to the desired use and amount of contents to be sampled. The wells are preferably interconnected and arranged in a uniform array, with uniform depths so that the tops and bottoms of the wells are planar or substantially planar. Preferably the array of wells comprises parallel rows of wells and parallel columns of wells, such that each well not situated on the outer perimeter of the plate is surrounded by eight other wells. Preferably the plates 20 and 20 A are generally rectangular, and as shown in FIGS. 7 and 8 , plate 20 is stacked on top of a collection plate 22 . Alternatively, as shown in FIG. 11 , plate 20 A is stacked on top of a plate 20 , which is stacked on top of collection plate 22 . The filter plates 20 and 20 A can be of a conventional design.
Each of the wells 21 of the filter plate 20 includes a membrane or porous structure (not shown) sealed to or positioned in the well. The sealing can be accomplished by any suitable means, including heat-sealing, sealing with ultrasonics, solvents, adhesives, by diffusion bonding, compression such as by a ring or skive, etc. The type of membrane suitable is not particularly limited, and by way of example can include nitrocellulose, cellulose acetate, polycarbonate, polypropylene and PVDF microporous membranes, or ultrafiltration membranes such as those made from polysulfone, PVDF, cellulose or the like. Additionally, materials also include glass fibers, glass mats, glass cloths, depth filters, nonwovens, woven meshes and the like or combinations there of, depending upon the application, or the membrane can be cast-in-place as disclosed in U.S. Pat. Nos. 6,048,457 and 6,200,474, the disclosures of which are hereby incorporated by reference. A single membrane covering all of the wells could be used, or each well can contain or be associated with its own membrane that can be the same or different from the membrane associated with one or more of the other wells. Each such membrane support is preferably coextensive with the bottom of its respective well.
Each of the wells 21 of the filter plate 20 also includes an outlet, preferably in the form of a spout that is centrally located with respect to each well 21 and preferably does not extend below the plate skirt.
The collection plate 22 preferably is also generally rectangular, and includes a plurality of openings 23 . Each opening 23 corresponds to a well 21 of the filtration plate, such that when in the assembled condition, each well 21 of the filter plate 20 is registered with and thus in fluid communication with a respective opening 23 of the collection plate 22 . Each opening 23 terminates in a bottom 25 , which is preferably closed unless it is an intermediate plate with a collection plate below it or the manifold itself acts as a sump or collection plate where optionally a spacer, such as is shown in FIG. 3 and discussed below, may be used. The collection plate 22 can be of a conventional design.
The filter plate 20 has a lower peripheral skirt 27 that allows it to be stacked over the collection plate 22 . When the filter plate 20 is stacked over the collection plate 22 as in the FIG. 1 embodiment, proper alignment is ensured, such that each of the spouts is positioned directly over and in close proximity to a respective opening 23 in the collection plate 22 . The proximity and alignment of each spout with a respective opening prevents cross-talk among neighboring wells. The stacked plates are positioned inside the base 12 as an integral unit. The collar 14 is positioned over the two plates and sits against the base flange gasket 5 , which seals the base 12 to the collar 14 . This also positions the collar gasket 75 on the top perimeter edge of the filter plate 20 . When vacuum is applied to the manifold, the collar 14 is the only moving component. As additional vacuum is applied, the vacuum causes the collar 14 to compress both gaskets. However, the filter plate 20 and collection plate 21 remain fixed in the loaded position because they make up a solid stack assembly that includes the base 12 , the collection plate 21 and the filter plate 20 that is independent of and not influenced by the relative movement of the collar 14 . Thus, the stack height of the filter plate and collection plate remains constant. A liquid handler can be programmed to dispense onto the membrane in the filter plate 20 , regardless of whether the assembly is under vacuum, since the stack height is not changed by the application of vacuum. The assembly, therefore, is readily adaptable to automation protocols and allows for quantitative filtrate transfer.
Similarly, when using an alternative embodiment of one seal such as shown in FIGS. 9 and 10 a similar sealing action occurs wherein the collar 14 moves to compress the gasket. The height of the plate(s) remains the same with or without the application of the vacuum.
Since the manifold design of the present invention is modular, different components can be positioned between the base and the collar (as mentioned above), allowing a variety of applications to be performed. In one embodiment, ( FIG. 3 ) where the application requires a filter plate 20 , but does not require a collection plate 22 , a spacer or removable support 80 can replace the collection plate thereby maintaining the unit stack height ( FIG. 3 ). The spacer or removable support 80 positions the filter plate 20 in the proper x- and y-axis orientation so that robotics can deliver sample to the wells 21 of the filter plate 20 . It also positions the filter plate 20 at the proper stack height so that the collar 14 can seal to the base 12 and plate 20 simultaneously upon the application of vacuum. Accordingly, preferably the spacer or support 80 is dimensioned similar to the collection plate 20 , as shown. In the embodiment shown, the spacer or support 80 includes a central beam 81 (positioned so as to not interfere with the operation of the filter plate) to help support the filter plate 20 .
The top seal gasket 75 on the collar 14 can be used to create a seal when it is desired to carry out a quick wash procedure by placing the filter plate on top of the collar 14 rather than inside the manifold assembly. Indeed, this gasket can accept a variety of support structures for use with unique applications, such as a MULTISCREEN®. Underdrain support grid commercially available from Millipore Corporation.
FIGS. 7 and 8 illustrate one embodiment of a bottom gasket 5 ′. In this embodiment, the gasket 5 ′ is positioned in the groove 6 in base 12 as best seen in FIG. 8 . It includes a wiper portion 51 that extends above the groove 6 and into recess 6 ′ formed in skirt 15 of the collar 14 as shown. The height of the wiper portion 51 and its position in the recess 6 ′ allows for some variability in the positioning of the collar 14 and base 12 (and thus variability in the stack height of the components contained between the collar and base) without sacrificing the integrity of the seal.
FIGS. 4A and 4B illustrate a further embodiment of the manifold of the present invention. This embodiment is useful for the direct transferring of eluant from filter plate 20 to one or more MALDI targets. Specifically, sample preparation prior to analysis by MALDI-TOF Mass Spectrometry often involves desalting and concentration of samples (e.g., peptides). Simultaneous preparation and analysis of multiple samples is often desirable, and can be carried out using the manifold assembly of the present invention. Accordingly, instead of the collection plate 21 of the embodiment of FIG. 1 , or the support tray of the embodiment of FIG. 3 , a target tray 40 is used. The design of the target tray 40 is not particular limited, and will depend upon the configuration of the target(s) chosen. The tray 40 can hold one or more targets. For example, in the FIG. 4A embodiment, four MALDI targets 41 commercially available from Applera Corporation are used. Alternatively, as shown in FIG. 4B , a single target 41 ′ such as a MALDI target commercially available from Bruker Daltonics can be used. The target tray 40 is positioned under the spouts of each well in the filter plate 20 , with the correct stack height enabling the collar 14 to seal against the base 12 as before. As in the embodiments of FIGS. 1 and 3 , the application of vacuum (e.g., the transition from atmospheric pressure to a different pressure) does not result in any z-axis movement of the operative component, which in this case is the filter plate stacked on top of the MALDI target(s).
In each of these embodiments, the stack height is critical to the sealing of the assembly. If a deep well filter plate were used, for example, a taller collar 14 and/or base 12 , or an extension with appropriately located additional sealing gaskets, can be used, to insure the seal between the top of the plate and the flange on the base 12 . FIG. 12 shows the use of a deep well filter plate 20 B with a regular depth collection plate 22 in which the plate is designed to fit within the opening of the collar 14 so that a longer collar and/or base is not needed. FIG. 13 shows a system using a deep well filter plate 20 B and a deep well collection plate 22 B. In this embodiment, the collar 14 B has been made taller to provide the exact height requirement for the desired plates used.
The components of the stacked unit (e.g., the filter plate 20 and collection plate 22 , or the filter plate 20 , target 41 and target tray 40 ) do not move independently of one another, since they are positioned in stacked relationship on the base 12 and any movement is limited to the collar 14 . As a result, their relative position remains constant regardless of whether the assembly is under vacuum, thereby allowing a liquid handler to be programmed to dispense to the unit, for example.
FIGS. 5 and 6 illustrate the versatility of the manifold assembly of the present invention. In this embodiment, the collar 14 is place in sealing relationship with base 12 , and a sample preparation device such as a multiwell plate 20 is placed on the top surface of the collar 14 . An optional grid 37 can be positioned under the plate 20 to assist in supporting the plate 20 . The plate 20 seals against the top gasket positioned in the collar 14 . Accordingly, vacuum can be used as the driving force to filter sample through the plate 20 . This enables a quick wash procedure without having to place the filter plate inside the manifold. The top gasket can accept a wide variety of support structures for use with unique applications, such as a 384 SEQ plate rib structure for drop removal and a Multiscreen® underdrain support grid, both commercially available from Millipore Corporation.
Since the modular design of the manifold assembly allows for various applications, the components of the present invention can be sold as a kit. For example, several different size collars can be provided in the kit in order to accommodate sample processing devices having different stack heights, such as where deep well filtration plates are used. Similarly, numerous different sample processing devices can be provided in the kit, including filtration plates with membranes of different functionality, collection plates, MALDI TOF targets, support grids, underdrains, washing inserts, etc. | A laboratory device design particularly for a multiplate format that includes a manifold wherein the position of the plate is not a function of gasket compression or vacuum rate applied. In one embodiment, the device has a modular design, wherein one or more removable inserts, preferably with different functionalities can be positioned between a base component and a collar component. The particular insert(s) chosen depend on the desired sample preparation or assay to be carried out. The insert(s) are stacked and are positioned between the base and collar as a unit, so that the stack within the manifold does not move during evacuation of the vacuum chamber. The consistent position of the insert(s) facilitates using vacuum sample processing with automated liquid handlers. | 1 |
FIELD OF THE INVENTION
The present invention pertains to a device for fixing the dies in the die table of a tabletting machine, especially of a rotary tabletting machine, by means of die holders.
BACKGROUND OF THE INVENTION
Modern tabletting machines are suitable for pressing tablets of a great variety of types and shapes. After one batch or a plurality of batches of tablets have been manufactured, the press molds must be removed for cleaning and subsequently mounted. Disassembly is also necessary when the machine is retrofitted from one tablet format to another tablet format. To do so, the punches and dies must be replaced. Tabletting machines, in which the dies are fixed and locked or can be detached by means of die screws, which are screwed into the die table from the outside, have been known. As many die screws are needed as there are dies. The die screws are conical at the front end and engage circumferential grooves of the dies with the conical end during screwing in for fixing the dies. Every individual die screw must be removed manually one after the other at the time of replacement in order to remove the dies of the old batch. After removal of the old dies and insertion of the new dies, all die screws must again be tightened one by one manually for fixing and locking. This time-consuming process of die replacement is unsatisfactory especially in the case of smaller batches, because the time requirement for replacing the dies means machine downtime. However, high operating times should be reached precisely with modern machines, which have a considerable investment value.
SUMMARY AND OBJECTS OF THE INVENTION
The basic object of the present invention is therefore to provide a device with which both rapid removal of the old dies and rapid fixation of the new dies in the die table are possible.
According to the invention, a device for fixing the dies in the die table of a tabletting machine is provided. The tabletting machine is particularly a rotary tabletting machine. Die holders are provided arranged between a rotor axis and a pitched circle of the dies. Die holder moving means is provided for moving the die holders together (in unison). The die holder moving means is provided on the die table. Rapid and simple replacement of the dies is made possible by the use according to the present invention of a device for the joint movement of the die holders in the die table and by the arrangement of the die holders of the die table between two dies, which are arranged on the reference circle of the die table.
The die holders are arranged in holes that are radial in relation to the rotor axis. The die holder movement means is preferably designed as a hydraulic device and the die holders are designed as hydraulic pistons with conical heads. Screw plugs are provided with springs, the plugs being screwed into radial holes on the outer edge of the die table. Die pins, which press the springs of the screw plugs, are arranged at the die holders.
The die holders may also be designed as cams on a ring disc mounted in the die table. Further, the die holders may be designed as circle segments movable radially from the inside toward the dies and a ring disc, which is mounted in the die table and engages obliquely positioned elongated holes of the circle segments with pins, is also provided. The ring disc is driven by means of a piston.
The die holders are preferably designed as lever pairs which are expanded by spring elements that are mounted and pivotable in the die table. The levers can be actuated by push rods wherein pressure can be emitted radially from the inside.
The various features of novelty which characterize the invention are pointed out with particularity in the claims annexed to and forming a part of this disclosure. For a better understanding of the invention, its operating advantages and specific objects attained by its uses, reference is made to the accompanying drawings and descriptive matter in which preferred embodiments of the invention are illustrated.
BRIEF DESCRIPTION OF THE DRAWINGS
In the drawings:
FIG. 1 is a vertical partial sectional view through a rotary tabletting machine;
FIG. 1A is an enlarged partial sectional view of the die holder assembly of FIG. 1;
FIG. 2 is a partially cutaway partial top view of the die table;
FIG. 3 is a partially cut away partial top view of the die table according to another embodiment of the invention;
FIG. 4 is a partially cut away partial top view of the die table according to another embodiment of the invention; and
FIG. 5 is a partially cut away partial top view of still another embodiment of the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
FIG. 1 shows a vertical partial section through a rotary tabletting machine 12. This machine is comprised of a die table 4, which is connected to a rotor 1, which is driven via a drive shaft 13 rotating around a vertical rotor axis 14, and is formed by a rotor upper part 15 and a rotor lower part 16, in which respective upper punches 3 and lower punches 2 are guided. The upper punch 3 is adjusted by means of a guide sleeve 26, which is designed with a groove, as well as by means of a feather key 25. The guide sleeve 26 of the upper punch 3 is fastened with an adapter 23 with an associated screw 24. The lower punch 2 is also adjusted by means of a guide sleeve 27 and a feather key 25. The lower punch 2 located in the guide sleeve 27 is fastened by means of an adapter 23 and a screw 24. In the die table 4, dies 10 are uniformly arranged on the reference circle 17 of the die table 4. When the die table 4 rotates during the operation of the rotary tabletting machine 12, the dies 10 with the upper punches 3 and lower punches 2 belonging to them consecutively reach a pressing station, where the filling material contained in the die 10 is pressed into the finished tablet by means of pressure rollers. The pressing station and the pressure rollers are not shown in FIG. 1. The same applies to the filling shoes, whose task it is to fill the filling material after the pressing process into the now empty die 10.
Each die 10 is comprised of a metallic die body 18 and a through hole 19, which forms the mold for pressing the tablet and has an annular groove 11 on its outer circumference. The die holder 5 is designed as a hydraulic piston 20 with a conical clamping head 21 and is provided with an extended die pin 6, which presses a spring 8 of a screw plug 7. The latter is securely screwed into the radial hole 22 in the die table 4 from the outside. The pressing force of a hydraulic device, not shown, is simultaneously transmitted to the piston-like die holder 5 by a pressure feed means 9 guided by the rotor 1.
FIG. 2 shows a partial top view of the die table 4. The dies 10 are uniformly distributed on the reference circle 17. The die holders 5 are designed as hydraulic pistons 20, at the ends of which the die pins 6 are arranged. The conical clamping head 21 of the die holder 5 engages the annular grooves 11 of the dies 10 during fixation. Two die holders 5 thus wedge in a die 10 such that it is secured against vertical and axial displacements during the pressing process. Since one die holder 5 engages annular grooves 11 of the dies 10 arranged to the left and right of it, the number of die holders 5 needed equals that of the dies. The screw plugs 7 are screwed from the outside into the die table 4. The screw plugs are provided with springs 8. These screw plugs 7 are located in the same radial holes 22 as the die holders 5 belonging to them. During the fixation process, the die pins 6 of the die holders 5 press the springs 8 of the screw plugs 7, so that the springs 8 are compressed after the fixation process. If the dies 10 are to be replaced, the hydraulic means is switched off, so that no more force is exerted on the die holders 5 in the direction of the dies 10 via the pressure feed means 9. However, the die holders 5 must be moved away from the dies 10 in order to remove the dies 10. The springs 8 of the screw plugs 7, which are compressed during the fixation, are released and press the die holders 5 radially in the inward direction from the dies 10. This happens simultaneously for all dies 10. The dies 10 can then be removed from the die table 4, the new dies 10 can be inserted, and simultaneously fixed by means of the hydraulic means. This facilitates and expedites the cleaning process of the machines and the die replacement.
Another embodiment for central fastening of the dies 10 consists of designing the die holders 5 as cams 28 on a ring disk 29 mounted in the die table 4, which is driven via, e.g., a pinion 31 (see FIG. 3). Rotation of the pinion 31 in one direction 50 results in fixing the die and rotation of the die in the opposite direction 52 results in loosening the die.
Another mechanical embodiment is the design of the die holders 5 as lever pairs 35 which are expanded by spring elements and 34 are mounted and pivotable in the die table 4. The levers are actuated by push rods 36 to which pressure can be admitted radially from the inside (see FIG. 5). Movement of the push rods 36 in one direction 54 results in fixing the die and movement of the push rods 36 in the opposite direction 56 results in loosening the die. It is also possible to design the die holders 5 as circle segments 30 movable radially from the inside toward the dies 10. The circle segments 30 are provided with obliquely positioned elongated holes 33. A ring disk 29 mounted in the die table 4, which is driven by, e.g., a pinion 31, then engages the obliquely positioned elongated holes of the circle segments with pins 32 during the fastening process (see FIG. 4). Rotation of the pinion 31 in one direction 50 results in fixing the die and rotation of the die in the opposite direction 52 results in loosening the die.
While specific embodiments of the invention have been shown and described in detail to illustrate the application of the principles of the invention, it will be understood that the invention may be embodied otherwise without departing from such principles. | A device for fixing the dies in the die table of a tabletting machine, especially of a rotary tabletting machine, using die holders. To make it possible to rapidly remove the old dies and to rapidly fix the new dies during the replacement of the dies for cleaning the machine, the die holders are arranged between the rotor axis and the pitch circle of the dies, and structure is provided for jointly moving the die holders on the die table. | 1 |
TECHNICAL FIELD
[0001] The present invention relates to a fuel injector and a gas turbine.
BACKGROUND ART
[0002] For environment protection purposes, it is desirable to reduce a nitrogen oxide (NOx) exhausted from a gas turbine. As a method of reducing the exhaust amount of NOx, there is a method in which fuel and compressed air are fully mixed (perfectly pre-mixed), and the resulting air-fuel mixture is injected from a fuel injector and combusted. In accordance with this method, since combustion is performed quickly, an increase in a combustion temperature can be suppressed. Therefore, generation of NOx (thermal NOx) due to the increase in the combustion temperature can be suppressed (see Patent Literature 1).
CITATION LIST
Patent Literature
[0003] Patent Literature 1: Japanese Laid-Open Patent Application Publication No. 2010-216668
SUMMARY OF INVENTION
Technical Problem
[0004] If the fuel and the compressed air are pre-mixed in large amounts in the interior of the fuel injector, a “flashback flame” may occur, in which a flame propagates from a combustion chamber to the fuel injector, and cause burning damages to the fuel injector. In particular, in a case where a gas with a high reactivity, such as a hydrogen gas, is used as the fuel, the flashback flame tends to occur.
[0005] In view of the above-described circumstances, the present invention has been developed. An object of the present invention is to provide a fuel injector which can reduce the generation amount of NOx and suppress the occurrence of a flashback flame.
Solution to Problem
[0006] A fuel injector of the present invention comprises a cylindrical passage which opens in a combustion chamber; a fuel introduction passage which guides fuel to a region of the cylindrical passage which is closer to the combustion chamber; and an air introduction passage which guides compressed air to the cylindrical passage at a location that is upstream of a location at which the fuel is introduced to the cylindrical passage, wherein the fuel introduction passage guides the fuel in a tangential direction of the cylindrical passage in a transverse sectional view.
[0007] In accordance with this configuration, the fuel is injected into the combustion chamber while swirling along the inner peripheral surface of the cylindrical passage, and is formed in a sheet shape (a spiral band shape) in the interior of the combustion chamber. At this time, the surface area of the fuel as a series of substances is large, and a distance between the outer surface of the fuel and the center of the fuel is short. This makes it possible to shorten combustion reaction time, and reduce the generation amount of NOx. Since the compressed air flows from the cylindrical passage toward the combustion chamber, it becomes possible to suppress a combustion gas from becoming stagnant in the vicinity of the exit of the cylindrical passage, and stable combustion can be carried out. Further, since the fuel and the air are not pre-mixed in large amounts in the interior of the fuel injector, the occurrence of a flashback flame can be suppressed.
[0008] In the above-described fuel injector, the air introduction passage may have a configuration which causes the compressed air to swirl in the same direction as a direction in which the fuel swirls, in an interior of the cylindrical passage. In accordance with this configuration, the swirling of the fuel is facilitated by the swirling compressed air. Therefore, the fuel can be formed in the sheet shape with a higher reliability.
[0009] In the above-described fuel injector, the fuel introduction passage may guide the fuel in a direction that is inclined toward the combustion chamber with respect to a direction perpendicular to a center axis of the cylindrical passage. In accordance with this configuration, hydrogen is less likely to become stagnant in the vicinity of the exit of the cylindrical passage. Therefore, the risk of occurrence of the flashback flame can be reduced even when a gas with a high reactivity, such as a hydrogen gas, is used.
[0010] According to another aspect of the present invention, a fuel injector comprises a plurality of cylindrical passages which open in a combustion chamber; a plurality of fuel introduction passages which guide fuel to regions of the plurality of cylindrical passages, respectively, which are closer to the combustion chamber; and a plurality of air introduction passages which guide compressed air to the plurality of cylindrical passages, respectively, at locations that are upstream of locations at which the fuel is introduced to the plurality of cylindrical passages, wherein the fuel introduction passages guide the fuel in tangential directions of the cylindrical passages, in transverse sectional views, respectively.
[0011] A gas turbine of the present invention comprises any one of the above-described fuel injectors.
Advantageous Effects of Invention
[0012] As described above, in accordance with the above-described fuel injector, it becomes possible to reduce the generation amount of NOx and suppress the occurrence of a flashback flame.
BRIEF DESCRIPTION OF DRAWINGS
[0013] FIG. 1 is a view schematically showing the overall configuration of a gas turbine.
[0014] FIG. 2 is a view schematically showing the configuration of a combustor.
[0015] FIG. 3 is a perspective view of a supplemental fuel injector.
[0016] FIG. 4 is a longitudinal sectional view of the supplemental fuel injector.
[0017] FIG. 5 is a cross-sectional view taken in the direction of arrows along line A-A of FIG. 4 , showing a first fuel introduction passage.
[0018] FIG. 6 is a cross-sectional view taken in the direction of arrows along line A-A of FIG. 4 , showing a second fuel introduction passage.
[0019] FIG. 7 is a cross-sectional view taken in the direction of arrows along line A-A of FIG. 4 , showing a third fuel introduction passage.
[0020] FIG. 8 is a cross-sectional view taken in the direction of arrows along line B-B of FIG. 4 .
[0021] FIG. 9 is a cross-sectional view taken in the direction of arrows along line C-C of FIG. 4 .
[0022] FIG. 10 is a view showing a positional relationship between the fuel introduction passage and an air introduction passage.
DESCRIPTION OF EMBODIMENTS
[0023] Hereinafter, the embodiment of the present invention will be described with reference to the drawings. Throughout the drawings, the same or corresponding components are designated by the same reference symbols and will not be described repeatedly.
[0024] <Configuration of Gas Turbine>
[0025] First of all, the overall configuration of a gas turbine 100 will be described. FIG. 1 is a view schematically showing the configuration of the gas turbine 100 . The gas turbine 100 of the present embodiment is a gas turbine for power generation, which drives a power generator 101 . The gas turbine 100 includes a compressor 10 , a combustor 11 , a fuel supply device 12 , and a turbine 13 .
[0026] Compressed air 102 is supplied from the compressor 10 to the combustor 11 . Fuel 103 is supplied from the fuel supply device 12 to the combustor 11 . In the present embodiment, it is supposed that a hydrogen gas with a high reactivity is used as the fuel 103 . Alternatively, the fuel 103 may be a natural gas, liquefied hydrogen, or the like. In the interior of the combustor 11 , the fuel 103 and the compressed air 102 are combusted. A combustion gas 104 in a high-temperature and high-pressure state generated by the combustion is supplied to the turbine 13 . The turbine 13 rotates by energy of the combustion gas 104 and drives the power generator 101 via the compressor 10 .
[0027] <Configuration of Combustor>
[0028] Next, the combustor 11 will be described more specifically. FIG. 2 is a cross-sectional view schematically showing the combustor 11 . The combustor 11 of the present embodiment is of a reverse flow can type in which the compressed air 102 and the combustion gas 104 flow in opposite directions. The combustor 11 includes a housing 20 , a combustion tube 21 , a main fuel injector 22 , and supplemental fuel injectors 23 . Alternatively, the combustor 11 may have a structure different from the reverse flow can type.
[0029] The housing 20 is a member defining the contour of the combustor 11 . The housing 20 includes a cylindrical outer pipe member 24 , and a disc-shaped end cover 25 provided at an end portion of the outer pipe member 24 on a first side (left side in FIG. 2 ).
[0030] The combustion tube 21 is housed inside the housing 20 . A combustion chamber 26 is formed inside the combustion tube 21 . In the interior of the combustion chamber 26 , the fuel 103 and the compressed air 102 are combusted to generate the combustion gas 104 . The generated combustion gas 104 flows to the right side in FIG. 2 and is supplied to the turbine 13 (see FIG. 1 ). Between the combustion tube 21 and the housing 20 , an annular air passage 27 is formed. The compressed air 102 supplied from the compressor 10 flows through the air passage 27 and toward the main fuel injector 22 (toward the left side in FIG. 1 ).
[0031] The main fuel injector 22 is mounted to the end cover 25 of the housing 20 to extend through the air passage 27 in the axial direction of the combustor 11 . The main fuel injector 22 is configured to take in the compressed air 102 which has flowed through the air passage 27 . The main fuel injector 22 injects the fuel 103 supplied from the fuel supply device 12 and the taken-in compressed air 102 into the combustion chamber 26 at the same time. Although in FIG. 2 , one main fuel injector 22 is shown, a plurality of main fuel injectors 22 may be provided. Further, a pilot fuel injector which injects the fuel in a small amount may be provided, separately from the main fuel injector 22 .
[0032] The supplemental fuel injectors 23 are mounted to the outer pipe member 24 of the housing 20 to extend through the air passage 27 in the radial direction of the combustor 11 . The supplemental fuel injectors 23 are configured to be capable of taking in a part of the compressed air 102 flowing through the air passage 27 . The supplemental fuel injectors 23 inject the fuel 103 supplied from the fuel supply device 12 and the taken-in compressed air 102 into the combustion chamber 26 at the same time. In the present embodiment, the plurality of supplemental fuel injectors 23 are arranged at equal intervals (e.g., intervals of 90 degrees) in the circumferential direction of the combustor 11 .
[0033] <Configuration of Fuel Injector>
[0034] Next, the configurations of the supplemental fuel injectors 23 will be described in detail. Each of the supplemental fuel injectors 23 of the present embodiment is a fuel injector which injects the fuel 103 in a sheet shape (hereinafter this fuel injector will be referred to as the fuel injector which uses “sheet injection method”). Although a case where the supplemental fuel injectors 23 are the fuel injectors which use the sheet injection method will be described below, both the main fuel injector 22 and the supplemental fuel injectors 23 may be the fuel injectors which use the sheet injection method, or only the main fuel injector 22 may be the fuel injector which uses the sheet injection method.
[0035] FIG. 3 is a perspective view of the supplemental fuel injector 23 . FIG. 4 is a longitudinal sectional view of the supplemental fuel injector 23 . As shown in FIG. 3 , the supplemental fuel injector 23 includes a first cylindrical section 30 located on a base end side (right upper side in FIG. 3 ), and a second cylindrical section 31 located on a tip end side (left lower side in FIG. 3 ) and having a diameter larger than that of the first cylindrical section 30 .
[0036] As shown in FIG. 4 , the supplemental fuel injector 23 includes a plurality of cylindrical passages 32 extending in the axial direction of the supplemental fuel injector 23 , a fuel passage 33 , a plurality of fuel introduction passages 34 , and a plurality of air introduction passages 35 .
[0037] The cylindrical passages 32 are passages which introduce the fuel 103 and the compressed air 102 into the combustion chamber 26 , while the fuel 103 and the compressed air 102 are swirling. The cylindrical passages 32 open in the combustion chamber 26 . As shown in FIG. 3 , among the plurality of cylindrical passages 32 , six inner cylindrical passages 32 A are arranged in the circumferential direction around the center axis of the supplemental fuel injector 23 , while twelve outer cylindrical passages 32 B are arranged in the circumferential direction around the center axis of the supplemental fuel injector 23 and located outward relative to the inner cylindrical passages 32 A.
[0038] As shown in FIG. 4 , the inner cylindrical passages 32 A are formed to extend over the first cylindrical section 30 and the second cylindrical section 31 , while the outer cylindrical passages 32 B are formed to extend only in the second cylindrical section 31 . Although in the present embodiment, the cylindrical passages 32 extend in parallel with each other, the cylindrical passages 32 may not necessarily extend in parallel with each other. For example, only the inner cylindrical passages 32 A may extend in the axial direction, while the outer cylindrical passages 32 B may extend radially outward to be inclined with respect to the axial direction.
[0039] The fuel passage 33 is a passage which delivers the fuel 103 supplied from the fuel supply device 12 (see FIG. 1 ) to the plurality of fuel introduction passages 34 which branch from the fuel passage 33 . As shown in FIG. 4 , the fuel passage 33 is located on the center axis of the supplemental fuel injector 23 and extends in the axial direction. As shown in FIG. 4 , the inner peripheral surface of the fuel passage 33 is formed with six fuel discharge ports 36 at equal intervals in the circumferential direction at three different axial locations. The fuel introduction passages 34 are connected to the fuel discharge ports 36 , respectively. In this structure, the fuel 103 in the interior of the fuel passage 33 flows to the fuel introduction passages 34 through the fuel discharge ports 36 . Although in the present embodiment, only one fuel passage 33 is formed, a plurality of fuel passages 33 may be formed.
[0040] The fuel introduction passages 34 are passages which guide the fuel 103 to the cylindrical passages 32 . In the description below, the fuel introduction passages 34 will be referred to as “first fuel introduction passages 34 A”, “second fuel introduction passages 34 B”, and “third fuel introduction passages 34 C”, respectively, in the order in which a distance between the fuel discharge ports 36 to which the fuel introduction passages 34 are connected and the combustion chamber 26 decreases. FIGS. 5 to 7 are cross-sectional views taken in the direction of arrows along line A-A of FIG. 4 , showing the first fuel introduction passages 34 A, the second fuel introduction passages 34 B, and the third fuel introduction passages 34 C, respectively.
[0041] As shown in FIG. 5 , the first fuel introduction passages 34 A extend from the fuel passage 33 to the six outer cylindrical passages 32 B, respectively, among the twelve outer cylindrical passages 32 B. The downstream end portions of the first fuel introduction passages 34 A are connected to the outer cylindrical passages 32 B, respectively in such a manner that the downstream end portions of the first fuel introduction passages 34 A extend in the tangential directions of the cylindrical passages 32 , in cross-sectional views, respectively. The downstream end portions of the first fuel introduction passages 34 A extend substantially in parallel with the radial direction of the supplemental fuel injector 23 .
[0042] As shown in FIG. 6 , the second fuel introduction passages 34 B extend from the fuel passage 33 to the six outer cylindrical passages 32 B, respectively, to which the first fuel introduction passages 34 A are not connected, among the twelve outer cylindrical passages 32 B. In the present embodiment, the outer cylindrical passages 32 B are provided in such a manner that the outer cylindrical passage 32 B to which the first fuel introduction passage 34 A is connected and the outer cylindrical passage 32 B to which the second fuel introduction passage 34 B is connected are arranged alternately in the circumferential direction of the supplemental fuel injector 23 . The downstream end portions of the second fuel introduction passages 34 B are connected to the outer cylindrical passages 32 B, respectively in such a manner that the downstream end portions of the second fuel introduction passages 34 B extend in the tangential directions of the outer cylindrical passages 32 B, in cross-sectional views, respectively. Note that the downstream end portions of the second fuel introduction passages 34 B extend in a direction that is inclined with respect to the radial direction of the supplemental fuel injector 23 , differently from the downstream end portions of the first fuel introduction passages 34 A.
[0043] As shown in FIG. 7 , the third fuel introduction passages 34 C extend from the fuel passage 33 to the six inner cylindrical passages 32 A, respectively. The downstream end portions of the third fuel introduction passages 34 C are connected to the inner cylindrical passages 32 A, respectively in such a manner that the downstream end portions of the third fuel introduction passages 34 C extend in the tangential directions of the inner cylindrical passages 32 A, in cross-sectional views, respectively. The downstream end portions (fuel injection ports 40 ) of the first fuel introduction passages 34 A, the downstream end portions (fuel injection ports 40 ) of the second fuel introduction passages 34 B, and the downstream end portions (fuel injection ports 40 ) of the third fuel introduction passages 34 C are located in the regions of the cylindrical passages 32 which are close to the combustion chamber 26 . The phrase “the regions located in the cylindrical passages 32 which are close to the combustion chamber 26 ” may be the regions closest to the combustion chamber 26 in a case where the cylindrical passages 32 are equally divided into three regions in the axial direction or the regions closest to the combustion chamber 26 in a case where the cylindrical passages 32 are equally divided into two regions in the axial direction.
[0044] As described above, the downstream end portions of all of the fuel introduction passages 34 are connected to the cylindrical passages 32 , respectively in such a manner that the downstream end portions of the fuel introduction passages 34 extend in the tangential directions of the cylindrical passages 32 , in the cross-sectional views, respectively. In this structure, the fuel 103 is introduced to the cylindrical passages 32 from the tangential directions of the cylindrical passages 32 , in the cross-sectional views (transverse sectional views) perpendicular to the center axes of the cylindrical passages 32 . Thus, the fuel 103 having been introduced into the cylindrical passages 32 swirl (swirl in a clockwise direction in FIGS. 5 to 7 ) along the inner peripheral surfaces of the cylindrical passages 32 , and thereafter are injected into the combustion chamber 26 . In this way, the fuel 103 swirl along the inner peripheral surfaces of the cylindrical passages 32 , and thereby is formed in the sheet shape.
[0045] As shown in FIG. 4 , the first fuel introduction passages 34 A include first longitudinal passage sections 37 extending in the axial direction, respectively, while the second fuel introduction passages 34 B include second longitudinal passage sections 38 , respectively, which extend in the axial direction, respectively, and are shorter than the first longitudinal passage sections 37 . On the other hand, the third fuel introduction passages 34 C do not include passage sections extending in the axial direction. With this configuration of the fuel introduction passages 34 , in all of the cylindrical passages 32 , the fuel injection ports 40 through which the fuel 103 is introduced to the cylindrical passages 32 are located at a substantially equal distance from the exits of the cylindrical passages 32 .
[0046] The air introduction passages 35 are passages which guide the compressed air 102 to the cylindrical passages 32 . As shown in FIG. 3 , the first cylindrical section 30 is formed with air inlets 41 A for the inner cylindrical passages 32 A, while the second cylindrical section 31 is formed with air inlets 41 B for the outer cylindrical passages 32 B. The air inlets 41 A, 41 B extend in the axial direction and are formed in a slit shape. As shown in FIG. 4 , the air introduction passages 35 connect the air inlets 41 A formed in the first cylindrical section 30 to the inner cylindrical passages 32 A, and connect the air inlets 41 B formed in the second cylindrical section 31 to the outer cylindrical passages 32 B. In this structure, the compressed air 102 outside the supplemental fuel injectors 23 can be introduced to the cylindrical passages 32 .
[0047] As shown in FIG. 4 , the air introduction passages 35 are located upstream of the fuel injection passages 34 (the fuel injection ports 40 ). In this structure, the compressed air 102 is guided to the regions of the cylindrical passages 32 that are upstream of the regions of the cylindrical passages 32 to which the fuel 103 is introduced. Therefore, the fuel 103 is injected into the combustion chamber 26 together with the compressed air 102 in such a manner that the fuel 103 is pushed out by the compressed air 102 .
[0048] FIG. 8 is a cross-sectional view taken in the direction of arrows along line B-B of FIG. 4 . FIG. 9 is a cross-sectional view taken in the direction of arrows along line C-C of FIG. 4 . As shown in FIGS. 8 and 9 , the air introduction passages 35 are connected to the cylindrical passages 32 , respectively in such a manner that the air introduction passages 35 extend in the tangential directions of the cylindrical passages 32 , in cross-sectional views, respectively. Therefore, in cross-sectional views (transverse sectional views) perpendicular to the center axes of the cylindrical passages 32 , the compressed air 102 can be guided to the cylindrical passages 32 from the tangential directions of the cylindrical passages 32 , respectively. Thus, the compressed air 102 having been introduced to the cylindrical passages 32 is injected into the combustion chamber 26 while swirling (swirling in the clockwise direction in FIGS. 8 and 9 ) along the inner peripheral surfaces of the cylindrical passages 32 .
[0049] FIG. 10 is a view showing a positional relationship between the fuel introduction passage 34 and the air introduction passage 35 , when viewed from the perspective of the combustion chamber 26 . In the example of FIG. 10 , the fuel introduction passage 34 is connected to the right side of the cylindrical passage 32 in FIG. 10 , while the air introduction passage 35 is connected to the lower side of the cylindrical passage 32 in FIG. 10 . The fuel 103 is introduced to the right side of the cylindrical passage 32 in FIG. 10 through the lower side in FIG. 10 , and swirls in a counterclockwise direction along the inner peripheral surface of the cylindrical passage 32 . In contrast, the compressed air 102 is introduced to the lower side of the cylindrical passage 32 in FIG. 10 through the left side in FIG. 10 , and swirls in the counterclockwise direction along the inner peripheral surface of the cylindrical passage 32 . In this way, in the present embodiment, the compressed air 102 swirls in the same direction as that of the fuel 103 . Therefore, in the present embodiment, the fuel 103 can swirl more easily and hence can be formed in the sheet shape more easily, as compared to, for example, a case where the compressed air 102 flows linearly in the axial direction.
[0050] Each of the air introduction passages 35 extends in a direction perpendicular to the center axis of the cylindrical passage 32 . Unlike in the case of the fuel 103 , even when the compressed air 102 which is swirling and the compressed air 102 which is introduced to the cylindrical passage 32 interfere with each other, this affects less the formation of the fuel 103 in the sheet shape.
[0051] The present embodiment has been described above. As described above, since the fuel 103 is formed in the sheet shape in the present embodiment, a distance between the outer surface of the fuel 103 and the center of the fuel 103 is short, and combustion reaction time of the fuel 103 is short. As a result, generation of NOx can be suppressed.
[0052] Although in the above-described embodiment, the air introduction passages 35 are connected to the cylindrical passages 32 , respectively in such a manner that the air introduction passages 35 extend in the tangential directions of the cylindrical passages 32 , in transverse sectional views, respectively, so that the compressed air 102 swirls in the same direction as that of the fuel 103 in the interiors of the cylindrical passages 32 , the configuration of the air introduction passages 35 is not limited to this. For example, the air introduction passages 35 may include swirlers provided on the outer peripheries of the cylindrical passages 32 , respectively to allow the compressed air 102 to swirl in the same direction as that of the fuel 103 in the interiors of the cylindrical passages 32 .
[0053] Although in the above-described embodiment, the fuel injector 23 includes the plurality of cylindrical passages 32 , the plurality of fuel introduction passages 34 , and the plurality of air introduction passages 35 , the fuel injector 23 may not include the plurality of these passages. For example, the fuel injector 23 may include one cylindrical passage 32 , one fuel introduction passage 34 and one air introduction passage 35 .
[0054] Although in the above-described embodiment, the cylindrical passages 32 , the fuel passage 33 , and the fuel introduction passages 34 are formed in the first cylindrical section 30 and the second cylindrical section 31 , the passages 32 to 34 may not be formed in the same members. For example, the passages 32 to 34 may be formed by independent pipe members, respectively, and coupled to each other to construct the fuel injector 23 .
[0055] Although in the above-described embodiment, the fuel injector 23 is used in the gas turbine 100 , the fuel injector 23 may be used in a boiler, an absorption chiller, or the like, as well as the gas turbine.
INDUSTRIAL APPLICABILITY
[0056] In accordance with the fuel injector of the present invention, the generation amount of NOx can be reduced, and the occurrence of a flashback flame can be suppressed. Therefore, the fuel injector of the present invention is useful in the technical field of the fuel injector.
REFERENCE SIGNS LIST
[0000]
22 main fuel injector
23 supplemental fuel injector
26 combustion chamber
32 cylindrical passage
32 A inner cylindrical passage
32 B outer cylindrical passage
34 fuel introduction passage
34 A first fuel introduction passage
34 B second fuel introduction passage
34 C third fuel introduction passage
35 air introduction passage
40 fuel introduction port
100 gas turbine
102 compressed air
103 fuel | A fuel injector ( 23 ) comprises a cylindrical passage ( 32 ) which opens in a combustion chamber ( 26 ), a fuel introduction passage ( 34 ) which guides fuel to a region of the cylindrical passage ( 32 ) which is closer to the combustion chamber ( 26 ), and an air introduction passage ( 35 ) which guides compressed air to the cylindrical passage ( 32 ) at a location that is upstream of a location at which the fuel is introduced to the cylindrical passage ( 32 ), wherein the fuel introduction passage ( 34 ) guides the fuel in a tangential direction of the cylindrical passage ( 32 ) in a transverse sectional view. | 5 |
This invention relates to a cathode-ray tube (CRT) and, more particularly to a color CRT including a tension focus mask.
BACKGROUND OF THE INVENTION
A color cathode-ray tube (CRT) typically includes an electron gun, an aperture mask-frame assembly, and a screen. The aperture mask-frame assembly is interposed between the electron gun and the screen. The screen is located on an inner surface of a faceplate of the CRT tube. The screen has an array of three different color-emitting phosphors (e.g., green, blue and red) formed thereon. The aperture mask functions to collimate the electron beams generated in the electron gun toward appropriate color-emitting phosphors on the screen of the CRT.
The aperture mask may be a focus mask. Focus masks typically comprise two sets of electrodes that are arranged orthogonal to each other, to form an array of openings. Different voltages are applied to the two sets of electrodes so as to create quadrupole focusing lenses in each opening of the mask, which are used to direct and focus the electron beams toward the appropriate color-emitting phosphors on the screen of the CRT tube.
One type of focus mask is a tension focus mask, wherein at least one of the sets of electrodes is under tension. Typically, for tension focus masks, the vertical electrodes are held in tension by the mask frame. The other set of electrodes is horizontal and overlays the vertical electrodes, which are typically strands. An etching process used on a flat sheet of metal commonly forms the strands. Such an etching process forms sharp corner edges along the length of the strands.
The two sets of electrodes overlap at a series of points known as junctions. At these junctions the individual elements of one set of electrodes are separated from the individual elements of the other set by an insulating material. When the different voltages are applied between the two sets of strands of the mask, to create the quadrupole focusing lenses in the openings thereof, surface flashover may occur at one or more of the junctions. Surface flashover is a breakdown process that may take place on or near the surface of the insulating material separating the two sets of strands and may lead to arcing between the strands at one or more places on the focus mask. Since the overlying wires are electrically connected to one another, all of the energy stored in the capacitance of the entire focus mask is available to arc. This stored energy may be sufficient to cause local melting of the strands and/or the insulating material and may result in an electrical short leading to the subsequent failure of the focus mask. Surface flashover has a greater risk of occurring in locations in which one of the electrodes has a sharp edge, since the local electric field can be higher at these locations.
Additionally, during operation of the CRT tube, electron scattering may occur along sharp edges of the mask strands. Electron scattering along strand edges of the focus mask is undesirable because some of these electrons may strike the wrong color element, degrading the color purity of the CRT tube.
Thus, a need exists for suitable tension focus masks that overcome the above-mentioned drawbacks.
SUMMARY OF THE INVENTION
The present invention relates to a color cathode-ray tube (CRT) having an evacuated envelope with an electron gun therein for generating at least one electron beam. The envelope further includes a faceplate panel having a luminescent screen with phosphor lines on an interior surface thereof. A tension focus mask, having a plurality of spaced-apart first conductive electrodes, is located generally parallel to an effective picture area of the screen. The plurality of spaced-apart first conductive electrodes, otherwise known as strands, have a screen-facing side and electron-gun facing side. Each side of the strands have sharp corner edges extending along the length of the strands. A plurality of second conductive electrodes are oriented substantially perpendicular to the plurality of strands and separated by an insulating material deposited on the screen-facing side and corners of the strands to shield the sharp edges of the strands from the second conductive electrodes. In doing so, the present invention reduces the risk of surface flashover that would occur when sharp corners are formed using prior art etching processes.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will now be described in greater detail, with relation to the accompanying drawings, in which:
FIG. 1 is a plan view, partly in axial section, of a color cathode-ray tube (CRT) including a uniaxial tension focus mask-frame assembly embodying the present invention;
FIG. 2 is a plan view of the uniaxial tension focus mask-frame assembly of FIG. 1;
FIG. 3 is a side view of the mask frame-assembly taken along line 3 — 3 of FIG. 2;
FIG. 4 is an enlarged section of the uniaxial tension focus mask shown within the circle 4 of FIG. 2; and
FIG. 5 is an enlarged view of a portion of the uniaxial tension focus mask taken along lines 5 — 5 of FIG. 4 .
DETAILED DESCRIPTION
FIG. 1 shows a color cathode-ray tube (CRT) 10 having a glass envelope 11 comprising a faceplate panel 12 and a tubular neck 14 connected by a funnel 15 . The funnel 15 has an internal conductive coating (not shown) that is in contact with, and extends from, a first anode button 16 to the neck 14 . A second anode button 17 , located opposite the first anode button 16 , is contacted by a second conductive coating (not shown).
The faceplate panel 12 comprises a viewing faceplate 18 and a peripheral flange or sidewall 20 that is sealed to the funnel 15 by a glass fort 21 . A three-color luminescent phosphor screen 22 is carried by the inner surface of the viewing faceplate 18 . The screen 22 is a line screen (not shown) that includes a multiplicity of screen elements comprised of red-emitting, green-emitting, and blue-emitting phosphor lines respectively, arranged in triads, each triad including a phosphor line of each of the three colors. Preferably, a light-absorbing matrix (not shown) separates the phosphor lines. A thin conductive layer (not shown), preferably formed of aluminum, overlies the screen 22 and provides a means for applying a uniform first anode potential to the screen 22 as well as for reflecting light, emitted from the phosphor elements, through the viewing faceplate 18 .
A multi-apertured color selection electrode, or uniaxial tension focus mask 25 , is removably mounted, by conventional means, within the faceplate panel 12 , in predetermined spaced relation to the screen 22 . An electron gun 26 , shown schematically by the dashed lines in FIG. 1, is centrally mounted within the neck 14 to generate and direct three inline electron beams 28 , a center and two side or outer beams, along convergent paths through the uniaxial tension focus mask 25 to the screen 22 . The inline direction of the center of the beams 28 is approximately normal to the plane of the paper.
The CRT of FIG. 1 is designed to be used with an external magnetic deflection yoke, such as the yoke 30 , shown in the neighborhood of the funnel-neck junction. When activated, the yoke 30 subjects the three electron beams 28 to magnetic fields that cause the beams to scan a horizontal and vertical rectangular raster across the screen 22 .
As shown in FIG. 2, the uniaxial tension focus mask 25 (shown schematically by the dashed lines in FIG. 2) includes two horizontal sides 32 , 34 and two vertical sides 36 , 38 . The two horizontal sides 32 , 34 of the uniaxial tension focus mask 25 are parallel with the central major axis, X, of the CRT while the two vertical sides 36 , 38 are parallel with the central minor axis, Y, of the CRT. A frame 45 , for the tension focus mask 25 , includes four major members, two horizontal members 46 , 48 to which the horizontal sides 32 , 34 of the tension focus mask 25 are attached and two vertical members 50 , 52 to which the second metal electrodes 60 are attached. Members 46 , 48 are substantially parallel to the major axis, X, and each other. The curvature of members 46 , 48 may be shaped to substantially match the specific curvature of the CRT screen (see FIG. 3 ). The horizontal sides 32 , 34 of the uniaxial tension focus mask 25 are welded to the two members 46 , 48 , which provide the necessary tension to the mask. The uniaxial tension focus mask 25 includes an apertured portion that overlies an effective picture area of the screen 22 . Referring to FIG. 4, which is an enlarged section of the uniaxial tension focus mask shown within the circle 4 of FIG. 2, the uniaxial tension focus mask 25 includes a plurality of first metal electrodes, or conductive strands 40 , separated by spaced slots 42 that parallel the minor axis, Y, of the CRT and the phosphor lines of the screen 22 . In the preferred embodiment slots 42 each have a width within a range of about 0.1 mm to about 0.5 mm (4-20 mils)? For a color CRT having a diagonal dimension of 68 cm, the strands 40 have widths in a range of about 0.2 mm to about 0.5 mm (8-20 mils) and slot 42 widths of about 0.2 mm to about 0.5 mm (8-20 mils). In a color CRT having a diagonal dimension of 68 cm (27 V), there are about 800 strands 40 . Each of the slots 42 extends from one horizontal side 32 of the mask to the other horizontal side 34 thereof (shown in FIG. 3 ).
FIG. 5 is an enlarged view of a portion of the uniaxial tension focus mask along lines 5 — 5 of FIG. 4 . Strands 40 , depicted in FIG. 5, are formed by an etching process performed on a flat metal plate. The etching process involves a sequence of operations suitable to form slots 42 . With the etching, new regions of the strands 40 are exposed. The preferred outcome is illustrated in FIG. 5 as strand 40 having a generally rectangular cross-section defined by screen-facing side 72 , electron-gun facing side 70 and side walls 75 . The etched strands 40 have associated with them a pair of relatively sharp edges at corners 43 and 44 being the top and bottom sharp edge portions shown in the embodiment of FIG. 5 . As shown in FIG. 5, the edge of comers 43 at the intersection of the screen-facing side 72 and side walls 75 form corners with a relatively less sharp edge than the edges formed at corners 44 . The shaper edges formed at corners 44 are positioned as far as possible from the cross-wires 60 to reduce the probability of surface flashover or arcing between the electrodes at one or more junctions. The arcing may be sufficient to cause local melting of the electrodes, destruction of the insulator, or both and may result in electrical short, leading to the subsequent failure of the focus mask. Further, the corners 43 closest to the cross-wires 60 is typically coated with an adhesive insulating material 62 , reducing triple-point electron emission from this region and thereby also reducing the incidence of surface flashover.
According to the preferred embodiment, the strands 40 each have a transverse dimension, or width, of about 0.1 mm to about 0.5 mm (4-20 mils) for both the screen-facing side 72 and the electron-gun-facing side 70 , with the screen-facing side 72 having a width about 0.025 to about 0.05 mm (1-4 mils) smaller than the width of the electron-gun-facing side 70 . Although the strands 40 may be inverted so that the wider side of the strands 40 is closest to the second conductive electrodes 60 , the above prescribed dimension of the strands 40 allows for less scatter of the electron beam 28 , thereby providing a measurable improvement in the color purity of the CRT. For example, in a conventional color CRT, the red x-coordinate is about 0.633. The red x-coordinate measured for a tension focus mask 25 incorporating the geometry described above, and shown in FIG. 5, is about 0.627, as compared with 0.613 for tension focus masks 25 , where the screen-facing side surface 72 is wider than the electron-gun-facing side 70 . A further advantage in having a narrower electron-gun-facing side 70 immediately adjacent the second conductive electrodes 60 is that the adhesive material 62 may be applied to the screen-facing side 72 and allowed to accumulate along the side walls 75 to corners 44 so as to shield the corners of the strands 40 thereby reducing the potential for surface flashover.
With reference to FIGS. 4 and 5, a plurality of second conductive electrodes 60 , each having a diameter of about 0.025 mm (1 mil), are disposed substantially perpendicular to the strands 40 and are bonded to the adhesive material 62 to electrically isolate the second conductive electrodes 60 from the strands 40 . The vertical spacing, or pitch, between adjacent second conductive electrodes 60 is about 0.33 mm (13 mils) for a color CRT 10 having a diagonal dimension of 68 cm (27 V). The uniaxial tension focus mask 25 , described herein, provides a mask transmission, at the center of the screen, of about 40-45%, and requires that the second anode, or focusing voltage, δV, applied to the second metal electrodes 60 , differs from the first anode voltage applied to the strands 40 by less than about 1 kV, for a first anode voltage of about 30 kV. The combination of the strands 40 and the second conductive electrodes 60 along with the different electric potentials applied thereto function to create the quadrupole fields, which converge the electron beams 28 onto the color-emitting phosphors on the screen 22 of the CRT 10 .
Although a single application of the insulative adhesive material 62 may be applied to the strands 40 , FIG. 5 illustrates the result of a multiple process for applying the adhesive material 62 . Such process includes applying a first coating of the insulative adhesive material 62 , e.g., by spraying, onto the screen-facing side 72 of the strands 40 . The strands 40 , in this example, are formed of either creep resistant steel or a low expansion alloy, such as INVAR™. The strands 40 each have a transverse dimension, or width, such that the screen-facing side 72 maintains a width about 0.025 to about 0.05 mm (1-4 mils) smaller than the width of the electron gun facing side 70 . The first coating of the insulative adhesive material 62 typically has a thickness of about 0.05 mm to about 0.1 mm (2-4 mils).
After the first coating of the insulative adhesive material 62 is hardened, a second coating of the insulative adhesive material 66 is applied over the first coating of the insulative adhesive material 62 . The second coating of the insulative adhesive material 66 may optionally have a different composition from that of the first coating. The second coating of the insulative adhesive material 66 typically has a thickness of about 0.0025 mm to about 0.05 mm (0.1 to 2 mils).
Thereafter, the second metal electrodes 60 are applied to the frame 45 , over the second coating of the insulative adhesive material 66 , such that the second metal electrodes 60 are substantially perpendicular to the strands 40 . The second metal electrodes 60 are applied using a winding fixture (not shown) that accurately maintains a desired spacing of, for example, about 0.33 mm (13 mils) between adjacent metal electrodes for a color CRT 10 having a diagonal dimension of about 68 cm (27 V).
The assembly is heated to a temperature of about 460° C. for about 30 minutes to cure the second coating of the insulative adhesive material 66 , thereby bonding the crosswires to the second coating of the insulative adhesive material 66 . Following curing, electrical connections are made to the strands 40 and second metal electrodes 60 , and the tension focus mask 25 is inserted into a tube envelope. | A color cathode-ray tube (CRT) having an evacuated envelope with an electron gun therein for generating at least one electron beam is disclosed. The envelope further includes a faceplate panel having a luminescent screen with phosphor lines on an interior surface thereof. A tension focus mask, having a plurality of spaced-apart first electrodes, is located adjacent to an effective picture area of the screen. The plurality of spaced-apart first electrodes has a screen-facing side having a predetermined width and a relatively wider electron-gun-facing side. Each side forming sharp corner edges extending along the length of each first electrodes. A substantially continuous insulating material is deposited on the screen-facing side and on the corners of the first electrodes to shield the sharp corner edges of the first electrodes. A plurality of second electrodes are oriented substantially perpendicular to the plurality of first electrodes and are bonded thereto by the insulating material layer. | 7 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation of co-pending application Ser. No. 11/170,484 filed Jun. 29, 2005 which is divisional of application Ser. No. 10/678,562 filed Oct. 3, 2003 which is a continuation-in-part of co-pending application Ser. No. 10/259,139, filed on Sep. 27, 2002, which is a continuation-in-part of co-pending application Ser. No. 10/123,389, filed on Apr. 16, 2002, both of which are incorporated herein by reference.
FIELD OF THE INVENTION
[0002] This invention relates to novel arylindenopyridines and arylindenopyrimidines and their therapeutic and prophylactic uses. Disorders treated and/or prevented using these compounds include neurodegenerative and movement disorders ameliorated by antagonizing Adenosine A2a receptors.
BACKGROUND OF THE INVENTION
Adenosine A2a Receptors
[0003] Adenosine is a purine nucleotide produced by all metabolically active cells within the body. Adenosine exerts its effects via four subtypes of cell-surface receptors (A1, A2a, A2b and A3), which belong to the G protein coupled receptor superfamily (Stiles, G. L. Journal of Biological Chemistry, 1992, 267, 6451). A1 and A3 couple to inhibitory G protein, while A2a and A2b couple to stimulatory G protein. A2a receptors are mainly found in the brain, both in neurons and glial cells (highest level in the striatum and nucleus accumbens, moderate to high level in olfactory tubercle, hypothalamus, and hippocampus etc. regions) (Rosin, D. L.; Robeva, A.; Woodard, R. L.; Guyenet, P. G.; Linden, J. Journal of Comparative Neurology, 1998, 401, 163).
[0004] In peripheral tissues, A2a receptors are found in platelets, neutrophils, vascular smooth muscle and endothelium (Gessi, S.; Varani, K.; Merighi, S.; Ongini, E.; Borea, P. A. British Journal of Pharmacology, 2000, 129, 2). The striatum is the main brain region for the regulation of motor activity, particularly through its innervation from dopaminergic neurons originating in the substantia nigra. The striatum is the major target of the dopaminergic neuron degeneration in patients with Parkinson's Disease (PD). Within the striatum, A2a receptors are co-localized with dopamine D2 receptors, suggesting an important site for the integration of adenosine and dopamine signaling in the brain (Fink, J. S.; Weaver, D. R.; Rivkees, S. A.; Peterfreund, R. A.; Pollack, A. E.; Adler, E. M.; Reppert, S. M. Brain Research Molecular Brain Research, 1992, 14, 186).
[0005] Neurochemical studies have shown that activation of A2a receptors reduces the binding affinity of D2 agonist to their receptors. This D2R and A2aR receptor-receptor interaction has been demonstrated in striatal membrane preparations of rats (Ferre, S.; von Euler, G.; Johansson, B.; Fredholm, B. B.; Fuxe, K. Proceedings of the National Academy of Sciences of the United States of America, 1991, 88, 7238) as well as in fibroblast cell lines after transfected with A2aR and D2R cDNAs (Salim, H.; Ferre, S.; Dalal, A.; Peterfreund, R. A.; Fuxe, K.; Vincent, J. D.; Lledo, P. M. Journal of Neurochemistry, 2000, 74, 432). In vivo, pharmacological blockade of A2a receptors using A2a antagonist leads to beneficial effects in dopaminergic neurotoxin MPTP(1-methyl-4-pheny-1,2,3,6-tetrahydropyridine)-induced PD in various species, including mice, rats, and monkeys (Ikeda, K.; Kurokawa, M.; Aoyama, S.; Kuwana, Y. Journal of Neurochemistry, 2002, 80, 262). Furthermore, A2a knockout mice with genetic blockade of A2a function have been found to be less sensitive to motor impairment and neurochemical changes when they were exposed to neurotoxin MPTP (Chen, J. F.; Xu, K.; Petzer, J. P.; Staal, R.; Xu, Y. H.; Beilstein, M.; Sonsalla, P. K.; Castagnoli, K.; Castagnoli, N., Jr.; Schwarzschild, M. A. Journal of Neuroscience, 2001, 21, RC143).
[0006] In humans, the adenosine receptor antagonist theophylline has been found to produce beneficial effects in PD patients (Mally, J.; Stone, T. W. Journal of the Neurological Sciences, 1995, 132, 129). Consistently, recent epidemiological study has shown that high caffeine consumption makes people less likely to develop PD (Ascherio, A.; Zhang, S. M.; Hernan, M. A.; Kawachi, I.; Colditz, G. A.; Speizer, F. E.; Willett, W. C. Annals of Neurology, 2001, 50, 56). In summary, adenosine A2a receptor blockers may provide a new class of antiparkinsonian agents (Impagnatiello, F.; Bastia, E.; Ongini, E.; Monopoli, A. Emerging Therapeutic Targets, 2000, 4, 635).
SUMMARY OF THE INVENTION
[0007] This invention provides a compound having the structure of Formula I or II
[0000]
or a pharmaceutically acceptable salt thereof, wherein
(a) R 1 is selected from the group consisting of
(i) —COR 5 , wherein R 5 is selected from H, optionally substituted C 1-8 straight or branched chain alkyl, optionally substituted aryl and optionally substituted arylalkyl;
wherein the substituents on the alkyl, aryl and arylalkyl group are selected from C 1-8 alkoxy, phenylacetyloxy, hydroxy, halogen, p-tosyloxy, mesyloxy, amino, cyano, carboalkoxy, or NR 7 R 8 wherein R 7 and R 8 are independently selected from the group consisting of hydrogen, C 1-8 straight or branched chain alkyl, C 3-7 cycloalkyl, benzyl, aryl, or heteroaryl or NR 7 R 8 taken together form a heterocycle or heteroaryl;
(ii) COOR 5 , wherein R 5 is as defined above; (ii) cyano; (iii) —CONR 9 R 10 wherein R 9 and R 10 are independently selected from H, C 1-8 straight or branched chain alkyl, C 3-7 cycloalkyl, trifluoromethyl, hydroxy, alkoxy, acyl, alkylcarbonyl, carboxyl, arylalkyl, aryl, heteroaryl and heterocyclyl;
wherein the alkyl, cycloalkyl, alkoxy, acyl, alkylcarbonyl, carboxyl, arylalkyl, aryl, heteroaryl and heterocyclyl groups may be substituted with carboxyl, alkyl, aryl, substituted aryl, heterocyclyl, substituted heterocyclyl, heteroaryl, substituted heteroaryl, hydroxamic acid, sulfonamide, sulfonyl, hydroxy, thiol, amino, alkoxy or arylalkyl, or R 9 and R 10 taken together with the nitrogen to which they are attached form a heterocycle or heteroaryl group;
(v) optionally substituted C 1-8 straight or branched chain alkyl;
wherein the substituents on the alkyl, group are selected from C 1-8 alkoxy, phenylacetyloxy, hydroxy, halogen, p-tosyloxy, mesyloxy, amino, cyano, carboalkoxy, carboxyl, aryl, heterocyclyl, heteroaryl, sulfonyl, thiol, alkylthio, or NR 7 R 8 wherein R 7 and R 8 are as defined above;
(b) R 2 is selected from the group consisting of optionally substituted alkyl, optionally substituted aryl, optionally substituted heteroaryl, optionally substituted heterocyclyl and optionally substituted C 3-7 cycloalkyl, C 1-8 alkoxy, aryloxy, C 1-8 alkylsulfonyl, arylsulfonyl, arylthio, C 1-8 alkylthio, or —NR 24 R 25
wherein R 24 and R 25 are independently selected from H, C 1-8 straight or branched chain alkyl, arylalkyl, C 3-7 cycloalkyl, carboxyalkyl, aryl, heteroaryl, and heterocyclyl or R 24 and R 25 taken together with the nitrogen form a heteroaryl or heterocyclyl group,
(c) R 3 is from one to four groups independently selected from the group consisting of:
hydrogen, halo, C 1-8 straight or branched chain alkyl, arylalkyl, C 3-7 cycloalkyl, C 1-8 alkoxy, cyano, C 1-4 carboalkoxy, trifluoromethyl, C 1-8 alkylsulfonyl, halogen, nitro, hydroxy, trifluoromethoxy, C 1-8 carboxylate, aryl, heteroaryl, and heterocyclyl, —NR 11 R 12 ,
wherein R 11 and R 12 are independently selected from H, C 1-8 straight or branched chain alkyl, arylalkyl, C 3-7 cycloalkyl, carboxyalkyl, aryl, heteroaryl, and heterocyclyl or R 10 and R 11 taken together with the nitrogen form a heteroaryl or heterocyclyl group,
—NR 13 COR 14 ,
wherein R 13 is selected from hydrogen or alkyl and R 14 is selected from hydrogen, alkyl, substituted alkyl, C 1-3 alkoxyl, carboxyalkyl, aryl, arylalkyl, heteroaryl, heterocyclyl, R 15 R 16 N(CH 2 ) p —, or R 15 R 16 NCO(CH 2 ) p —, wherein R 15 and R 16 are independently selected from H, OH, alkyl, and alkoxy, and p is an integer from 1-6, wherein the alkyl group may be substituted with carboxyl, alkyl, aryl, substituted aryl, heterocyclyl, substituted heterocyclyl, heteroaryl, substituted heteroaryl, hydroxamic acid, sulfonamide, sulfonyl, hydroxy, thiol, alkoxy or arylalkyl, or R 13 and R 14 taken together with the carbonyl form a carbonyl containing heterocyclyl group;
(d) R 4 is selected from the group consisting of hydrogen, C 1-6 straight or branched chain alkyl, benzyl
wherein the alkyl and benzyl groups are optionally substituted with one or more groups selected from C 3-7 cycloalkyl, C 1-8 alkoxy, cyano, C 1-4 carboalkoxy, trifluoromethyl, C 1-8 alkylsulfonyl, halogen, nitro, hydroxy, trifluoromethoxy, C 1-8 carboxylate, amino, NR 17 R 18 , aryl and heteroaryl,
—OR 17 , and —NR 17 R 18 ,
wherein R 17 and R 18 are independently selected from hydrogen, and optionally substituted C 1-6 alkyl or aryl; and
(e) X is selected from C═S, C═O; CH 2 , CHOH, CHOR 19 ; or CHNR 2 OR 21 where R 19 , R 20 , and R 21 are selected from optionally substituted C 1-8 straight of branched chain alkyl, wherein the substituents on the alkyl group are selected from C 1-8 alkoxy, hydroxy, halogen, amino, cyano, or NR 22 R 23 wherein R 22 and R 23 are independently selected from the group consisting of hydrogen, C 1-8 straight or branched chain alkyl, C 3-7 cycloalkyl, benzyl, aryl, heteroaryl, or NR 22 R 23 taken together from a heterocycle or heteroaryl;
with the proviso that in a compound of Formula II when R 1 is a cyano, then R 2 is not phenyl.
[0031] This invention also provides a pharmaceutical composition comprising the instant compound and a pharmaceutically acceptable carrier.
[0032] This invention further provides a method of treating a subject having a condition ameliorated by antagonizing Adenosine A2a receptors, which comprises administering to the subject a therapeutically effective dose of the instant pharmaceutical composition.
[0033] This invention further provides a method of preventing a disorder ameliorated by antagonizing Adenosine A2a receptors in a subject, comprising of administering to the subject a prophylactically effective dose of the compound of claim 1 either preceding or subsequent to an event anticipated to cause a disorder ameliorated by antagonizing Adenosine A2a receptors in the subject.
DETAILED DESCRIPTION OF THE INVENTION
[0034] Compounds of Formula I are potent small molecule antagonists of the Adenosine A2a receptors that have demonstrated potency for the antagonism of Adenosine A2a, A1, and A3 receptors.
[0035] Preferred embodiments for R 1 are COOR 5 wherein R 5 is an optionally substituted C 1-8 straight or branched chain alkyl. Preferably the alkyl chain is substituted with a dialkylamino group.
[0036] Preferred embodiments for R 2 are optionally substituted heteroaryl and optionally substituted aryl. Preferably, R 2 is an optionally substituted furan.
[0037] Preferred substituents for R 3 include hydrogen, halo, hydroxy, amino, trifluoromethyl, alkoxy, hydroxyalkyl chains, and aminoalkyl chains,
[0038] Preferred substituents for R 4 include NH 2 and alkylamino.
[0039] In a preferred embodiment, the compound is selected from the group of compounds shown in Tables 1 and 2 hereinafter.
[0040] More preferably, the compound is selected from the following compounds:
[0041] The compound of claim 1 , formula I, wherein R 4 is amino.
[0000]
2-amino-4-furan-2-yl-indeno[1,2-d]pyrimidin-5-one
[0000]
2-amino-4-phenyl-indeno[1,2-d]pyrimidin-5-one
[0000]
2-amino-4-thiophen-2-yl-indeno[1,2-d]pyrimidin-5-one
[0000]
2-amino-4-(5-methyl-furan-2-yl)-indeno[1,2-d]pyrimidin-5-one
[0000]
2,6-diamino-4-furan-2-yl-indeno[1,2-d]pyrimidin-5-one
[0000]
9H-indeno[2,1-c]pyridine-4-carbonitrile, 3-amino-1-furan-2-yl-9-oxo-
[0000]
9H-indeno[2,1-c]pyridine-4-carboxylic acid, 3-amino-1-furan-2-yl-9-oxo-, 2-dimethylamino-ethyl ester
[0000]
9H-indeno[2,1-c]pyridine-4-carboxylic acid, 3-amino-1-phenyl-9-oxo-, 2-dimethylamino-ethyl ester
[0000]
9H-indeno[2,1-c]pyridine-4-carboxylic acid, 3-amino-1-furan-2-yl-9-oxo-, (2-dimethylamino-1-methyl-ethyl)-amide
[0000]
9H-indeno[2,1-c]pyridine-4-carboxylic acid, 3-amino-1-furan-2-yl-9-oxo-, (2-dimethylamino-ethyl)-methyl-amide
[0000]
9H-indeno[2,1-c]pyridine-4-carboxylic acid, 3-amino-1-furan-2-yl-9-oxo-, 1-methyl-pyrrolidin-2-ylmethyl ester
[0053] The instant compounds can be isolated and used as free bases. They can also be isolated and used as pharmaceutically acceptable salts. Examples of such salts include hydrobromic, hydroiodic, hydrochloric, perchloric, sulfuric, maleic, fumaric, malic, tartaric, citric, benzoic, mandelic, methanesulfonic, hydroethanesulfonic, benzenesulfonic, oxalic, palmoic, 2-naphthalenesulfonic, p-toluenesulfonic, cyclohexanesulfamic and saccharic.
[0054] This invention also provides a pharmaceutical composition comprising the instant compound and a pharmaceutically acceptable carrier.
[0055] Pharmaceutically acceptable carriers are well known to those skilled in the art and include, but are not limited to, from about 0.01 to about 0.1 M and preferably 0.05 M phosphate buffer or 0.8% saline. Such pharmaceutically acceptable carriers can be aqueous or non-aqueous solutions, suspensions and emulsions. Examples of non-aqueous solvents are propylene glycol, polyethylene glycol, vegetable oils such as olive oil, and injectable organic esters such as ethyl oleate. Aqueous carriers include water, ethanol, alcoholic/aqueous solutions, glycerol, emulsions or suspensions, including saline and buffered media. Oral carriers can be elixirs, syrups, capsules, tablets and the like. The typical solid carrier is an inert substance such as lactose, starch, glucose, methyl-cellulose, magnesium stearate, dicalcium phosphate, mannitol and the like. Parenteral carriers include sodium chloride solution, Ringer's dextrose, dextrose and sodium chloride, lactated Ringer's and fixed oils. Intravenous carriers include fluid and nutrient replenishers, electrolyte replenishers such as those based on Ringer's dextrose and the like. Preservatives and other additives can also be present, such as, for example, antimicrobials, antioxidants, chelating agents, inert gases and the like. All carriers can be mixed as needed with disintegrants, diluents, granulating agents, lubricants, binders and the like using conventional techniques known in the art.
[0056] This invention further provides a method of treating a subject having a condition ameliorated by antagonizing Adenosine A2a receptors, which comprises administering to the subject a therapeutically effective dose of the instant pharmaceutical composition.
[0057] In one embodiment, the disorder is a neurodegenerative or movement disorder. Examples of disorders treatable by the instant pharmaceutical composition include, without limitation, Parkinson's Disease, Huntington's Disease, Multiple System Atrophy, Corticobasal Degeneration, Alzheimer's Disease, and Senile Dementia.
[0058] In one preferred embodiment, the disorder is Parkinson's disease.
[0059] As used herein, the term “subject” includes, without limitation, any animal or artificially modified animal having a disorder ameliorated by antagonizing adenosine A2a receptors. In a preferred embodiment, the subject is a human.
[0060] Administering the instant pharmaceutical composition can be effected or performed using any of the various methods known to those skilled in the art. The instant compounds can be administered, for example, intravenously, intramuscularly, orally and subcutaneously. In the preferred embodiment, the instant pharmaceutical composition is administered orally. Additionally, administration can comprise giving the subject a plurality of dosages over a suitable period of time. Such administration regimens can be determined according to routine methods.
[0061] As used herein, a “therapeutically effective dose” of a pharmaceutical composition is an amount sufficient to stop, reverse or reduce the progression of a disorder. A “prophylactically effective dose” of a pharmaceutical composition is an amount sufficient to prevent a disorder, i.e., eliminate, ameliorate and/or delay the disorder's onset. Methods are known in the art for determining therapeutically and prophylactically effective doses for the instant pharmaceutical composition. The effective dose for administering the pharmaceutical composition to a human, for example, can be determined mathematically from the results of animal studies.
[0062] In one embodiment, the therapeutically and/or prophylactically effective dose is a dose sufficient to deliver from about 0.001 mg/kg of body weight to about 200 mg/kg of body weight of the instant pharmaceutical composition. In another embodiment, the therapeutically and/or prophylactically effective dose is a dose sufficient to deliver from about 0.05 mg/kg of body weight to about 50 mg/kg of body weight. More specifically, in one embodiment, oral doses range from about 0.05 mg/kg to about 100 mg/kg daily. In another embodiment, oral doses range from about 0.05 mg/kg to about 50 mg/kg daily, and in a further embodiment, from about 0.05 mg/kg to about 20 mg/kg daily. In yet another embodiment, infusion doses range from about 1.0 μg/kg/min to about 10 mg/kg/min of inhibitor, admixed with a pharmaceutical carrier over a period ranging from about several minutes to about several days. In a further embodiment, for topical administration, the instant compound can be combined with a pharmaceutical carrier at a drug/carrier ratio of from about 0.001 to about 0.1.
DEFINITIONS AND NOMENCLATURE
[0063] Unless otherwise noted, under standard nomenclature used throughout this disclosure the terminal portion of the designated side chain is described first, followed by the adjacent functionality toward the point of attachment.
[0064] As used herein, the following chemical terms shall have the meanings as set forth in the following paragraphs: “independently”, when in reference to chemical substituents, shall mean that when more than one substituent exists, the substituents may be the same or different.
[0065] “Alkyl” shall mean straight, cyclic and branched-chain alkyl. Unless otherwise stated, the alkyl group will contain 1-20 carbon atoms. Unless otherwise stated, the alkyl group may be optionally substituted with one or more groups such as halogen, OH, CN, mercapto, nitro, amino, C 1 -C 8 -alkyl, C 1 -C 8 -alkoxyl, C 1 -C 8 -alkylthio, C 1 -C 8 -alkyl-amino, di(C 1 -C 8 -alkyl)amino, (mono-, di-, tri-, and per-) halo-alkyl, formyl, carboxy, alkoxycarbonyl, C 1 -C 8 -alkyl-CO—O—, C 1 -C 8 -alkyl-CO—NH—, carboxamide, hydroxamic acid, sulfonamide, sulfonyl, thiol, aryl, aryl(c 1 -c 8 )alkyl, heterocyclyl, and heteroaryl.
[0066] “Alkoxy” shall mean —O-alkyl and unless otherwise stated, it will have 1-8 carbon atoms.
[0067] The term “bioisostere” is defined as “groups or molecules which have chemical and physical properties producing broadly similar biological properties.” (Burger's Medicinal Chemistry and Drug Discovery, M. E. Wolff, ed. Fifth Edition, Vol. 1, 1995, Pg. 785).
[0068] “Halogen” shall mean fluorine, chlorine, bromine or iodine; “PH” or “Ph” shall mean phenyl; “Ac” shall mean acyl; “Bn” shall mean benzyl.
[0069] The term “acyl” as used herein, whether used alone or as part of a substituent group, means an organic radical having 2 to 6 carbon atoms (branched or straight chain) derived from an organic acid by removal of the hydroxyl group. The term “Ac” as used herein, whether used alone or as part of a substituent group, means acetyl.
[0070] “Aryl” or “Ar,” whether used alone or as part of a substituent group, is a carbocyclic aromatic radical including, but not limited to, phenyl, 1- or 2-naphthyl and the like. The carbocyclic aromatic radical may be substituted by independent replacement of 1 to 5 of the hydrogen atoms thereon with halogen, OH, CN, mercapto, nitro, amino, C 1 -C 8 -alkyl, C 1 -C 8 -alkoxyl, C 1 -C 8 -alkylthio, C 1 -C 8 -alkyl-amino, di(C 1 -C 8 -alkyl)amino, (mono-, di-, tri-, and per-) halo-alkyl, formyl, carboxy, alkoxycarbonyl, C 1 -C 8 -alkyl-CO—O—, C 1 -C 8 -alkyl-CO—NH—, or carboxamide. Illustrative aryl radicals include, for example, phenyl, naphthyl, biphenyl, fluorophenyl, difluorophenyl, benzyl, benzoyloxyphenyl, carboethoxyphenyl, acetylphenyl, ethoxyphenyl, phenoxyphenyl, hydroxyphenyl, carboxyphenyl, trifluoromethylphenyl, methoxyethylphenyl, acetamidophenyl, tolyl, xylyl, dimethylcarbamylphenyl and the like. “Ph” or “PH” denotes phenyl.
[0071] Whether used alone or as part of a substituent group, “heteroaryl” refers to a cyclic, fully unsaturated radical having from five to ten ring atoms of which one ring atom is selected from S, O, and N; 0-2 ring atoms are additional heteroatoms independently selected from S, O, and N; and the remaining ring atoms are carbon. The radical may be joined to the rest of the molecule via any of the ring atoms. Exemplary heteroaryl groups include, for example, pyridinyl, pyrazinyl, pyrimidinyl, pyridazinyl, pyrroyl, pyrazolyl, imidazolyl, thiazolyl, oxazolyl, isoxazolyl, thiadiazolyl, triazolyl, triazinyl, oxadiazolyl, thienyl, furanyl, quinolinyl, isoquinolinyl, indolyl, isothiazolyl, 2-oxazepinyl, azepinyl, N-oxo-pyridyl, 1-dioxothienyl, benzothiazolyl, benzoxazolyl, benzothienyl, quinolinyl-N-oxide, benzimidazolyl, benzopyranyl, benzisothiazolyl, benzisoxazolyl, benzodiazinyl, benzofurazanyl, benzothiopyranyl, indazolyl, indolizinyl, benzofuryl, chromonyl, coumarinyl, cinnolinyl, quinoxalinyl, indazolyl, pyrrolopyridinyl, furopyridinyl (such as furo[2,3-c]pyridinyl, furo[3,2-b]pyridinyl, or furo[2,3-b]pyridinyl), imidazopyridinyl (such as imidazo[4,5-b]pyridinyl or imidazo[4,5-c]pyridinyl), naphthyridinyl, phthalazinyl, purinyl, pyridopyridyl, quinazolinyl, thienofuryl, thienopyridyl, thienothienyl, and furyl. The heteroaryl group may be substituted by independent replacement of 1 to 5 of the hydrogen atoms thereon with halogen, OH, CN, mercapto, nitro, amino, C 1 -C 8 -alkyl, C 1 -C 8 -alkoxyl, C 1 -C 8 -alkylthio, C 1 -C 8 -alkyl-amino, di(C 1 -C 8 -alkyl)amino, (mono-, di-, tri-, and per-) halo-alkyl, formyl, carboxy, alkoxycarbonyl, C 1 -C 8 -alkyl-CO—O—, C 1 -C 8 -alkyl-CO—NH—, or carboxamide. Heteroaryl may be substituted with a mono-oxo to give for example a 4-oxo-1H-quinoline.
[0072] The terms “heterocycle,” “heterocyclic,” and “heterocyclo” refer to an optionally substituted, fully or partially saturated cyclic group which is, for example, a 4- to 7-membered monocyclic, 7- to 1′-membered bicyclic, or 10- to 15-membered tricyclic ring system, which has at least one heteroatom in at least one carbon atom containing ring. Each ring of the heterocyclic group containing a heteroatom may have 1, 2, or 3 heteroatoms selected from nitrogen atoms, oxygen atoms, and sulfur atoms, where the nitrogen and sulfur heteroatoms may also optionally be oxidized. The nitrogen atoms may optionally be quaternized. The heterocyclic group may be attached at any heteroatom or carbon atom.
[0073] Exemplary monocyclic heterocyclic groups include pyrrolidinyl; oxetanyl; pyrazolinyl; imidazolinyl; imidazolidinyl; oxazolyl; oxazolidinyl; isoxazolinyl; thiazolidinyl; isothiazolidinyl; tetrahydrofuryl; piperidinyl; piperazinyl; 2-oxopiperazinyl; 2-oxopiperidinyl; 2-oxopyrrolidinyl; 4-piperidonyl; tetrahydropyranyl; tetrahydrothiopyranyl; tetrahydrothiopyranyl sulfone; morpholinyl; thiomorpholinyl; thiomorpholinyl sulfoxide; thiomorpholinyl sulfone; 1,3-dioxolane; dioxanyl; thietanyl; thiiranyl; and the like. Exemplary bicyclic heterocyclic groups include quinuclidinyl; tetrahydroisoquinolinyl; dihydroisoindolyl; dihydroquinazolinyl (such as 3,4-dihydro-4-oxo-quinazolinyl); dihydrobenzofuryl; dihydrobenzothienyl; dihydrobenzothiopyranyl; dihydrobenzothiopyranyl sulfone; dihydrobenzopyranyl; indolinyl; isochromanyl; isoindolinyl; piperonyl; tetrahydroquinolinyl; and the like.
[0074] Substituted aryl, substituted heteroaryl, and substituted heterocycle may also be substituted with a second substituted-aryl, a second substituted-heteroaryl, or a second substituted-heterocycle to give, for example, a 4-pyrazol-1-yl-phenyl or 4-pyridin-2-yl-phenyl.
[0075] Designated numbers of carbon atoms (e.g., C 1-8 ) shall refer independently to the number of carbon atoms in an alkyl or cycloalkyl moiety or to the alkyl portion of a larger substituent in which alkyl appears as its prefix root.
[0076] Unless specified otherwise, it is intended that the definition of any substituent or variable at a particular location in a molecule be independent of its definitions elsewhere in that molecule. It is understood that substituents and substitution patterns on the compounds of this invention can be selected by one of ordinary skill in the art to provide compounds that are chemically stable and that can be readily synthesized by techniques known in the art as well as those methods set forth herein.
[0077] Where the compounds according to this invention have at least one stereogenic center, they may accordingly exist as enantiomers. Where the compounds possess two or more stereogenic centers, they may additionally exist as diastereomers. Furthermore, some of the crystalline forms for the compounds may exist as polymorphs and as such are intended to be included in the present invention. In addition, some of the compounds may form solvates with water (i.e., hydrates) or common organic solvents, and such solvates are also intended to be encompassed within the scope of this invention.
[0078] Some of the compounds of the present invention may have trans and cis isomers. In addition, where the processes for the preparation of the compounds according to the invention give rise to mixture of stereoisomers, these isomers may be separated by conventional techniques such as preparative chromatography. The compounds may be prepared as a single stereoisomer or in racemic form as a mixture of some possible stereoisomers. The non-racemic forms may be obtained by either synthesis or resolution. The compounds may, for example, be resolved into their components enantiomers by standard techniques, such as the formation of diastereomeric pairs by salt formation. The compounds may also be resolved by covalent linkage to a chiral auxiliary, followed by chromatographic separation and/or crystallographic separation, and removal of the chiral auxiliary. Alternatively, the compounds may be resolved using chiral chromatography.
[0079] This invention will be better understood by reference to the Experimental Details which follow, but those skilled in the art will readily appreciate that these are only illustrative of the invention as described more fully in the claims which follow thereafter. Additionally, throughout this application, various publications are cited. The disclosure of these publications is hereby incorporated by reference into this application to describe more fully the state of the art to which this invention pertains.
EXPERIMENTAL DETAILS
I. General Synthetic Schemes
[0080] Representative compounds of the present invention can be synthesized in accordance with the general synthetic methods described below and illustrated in the following general schemes. The products of some schemes can be used as intermediates to produce more than one of the instant compounds. The choice of intermediates to be used to produce subsequent compounds of the present invention is a matter of discretion that is well within the capabilities of those skilled in the art.
[0081] Procedures described in Schemes 1 to 7, wherein R 3a , R 3b , R 3c , and R 3d are independently any R 3 group, and R 1 , R 2 , R 3 , and R 4 are as described above, can be used to prepare compounds of the invention.
[0082] The substituted pyrimidines 1 can be prepared as shown in Scheme 1. The indanone or indandione 2 or the indene ester 3 can be condensed with an aldehyde to yield the substituted benzylidenes 4 (Bullington, J. L; Cameron, J. C.; Davis, J. E.; Dodd, J. H.; Harris, C. A.; Henry, J. R.; Pellegrino-Gensey, J. L.; Rupert, K. C.; Siekierka, J. J. Bioorg. Med. Chem. Lett. 1998, 8, 2489; Petrow, V.; Saper, J.; Sturgeon, B. J. Chem. Soc. 1949, 2134). This is then condensed with guanidine carbonate to form the indenopyrimidine 1.
[0000]
[0083] Alternatively, the pyrimidine compounds can be prepared as shown in Scheme 2. Sulfone 6 can be prepared by oxidation of the thiol ether 5 and the desired amines 7 can be obtained by treatment of the sulfone with aromatic amines.
[0000]
[0084] Pyrimidines with substituents on the fused aromatic ring could also be synthesized by the following procedure (Scheme 3). The synthesis starts with alkylation of furan with allyl bromide to provide 2-allylfuran. Diels-Alder reaction of 2-allylfuran with dimethylacetylene dicarboxylate followed by deoxygenation (Xing, Y. D.; Huang, N. Z. J. Org. Chem. 1982, 47, 140) provided the phthalate ester 8. The phthalate ester 8 then undergoes a Claisen condensation with ethyl acetate to give the styryl indanedione 9 after acidic workup (Buckle, D. R.; Morgan, N. J.; Ross, J. W.; Smith, H.; Spicer, B. A. J. Med. Chem. 1973, 16, 1334). The indanedione 9 is then converted to the dimethylketene dithioacetal 10 using carbon disulfide in the presence of KF. Addition of Grignard reagents to the dithioacetal 10 and subsequent reaction with guanidine provides the pyrimidines 11 as a mixture of isomers.
[0000]
[0085] Dihydroxylation and oxidation give the aromatic aldehydes 13 that can be reductively aminated to provide amines 14. The other isomer can be treated in a similar manner.
[0000]
[0086] 3-Dicyanovinylindan-1-one (15) (Scheme 5) was obtained using the published procedure (Bello, K. A.; Cheng, L.; Griffiths, J. J. Chem. Soc., Perkin Trans. II 1987, 815). Reaction of 3-dicyanovinylindan-1-one with an aldehyde in the presence of ammonium hydroxide produced dihydropyridines 16 (El-Taweel, F. M. A.; Sofan, M. A.; E.-Maati, T. M. A.; Elagamey, A. A. Boll. Chim. Farmac. 2001, 140, 306). These compounds were then oxidized to the corresponding pyridines 17 using chromium trioxide in refluxing acetic acid.
[0000]
[0087] The ketone of pyridines 17 can be reduced to provide the benzylic alcohols 18. Alternatively, the nitriles can be hydrolyzed with sodium hydroxide to give the carboxylic acids 19 (Scheme 6).
[0000]
[0088] The acids can then be converted to carboxylic esters 20 or amides 21 using a variety of methods. In general, the esters 20 are obtained by treatment with silver carbonate followed by an alkyl chloride or by coupling with diethylphosphoryl cyanide (DEPC) and the appropriate alcohol (Okawa, T.; Toda, M.; Eguchi, S.; Kakehi, A. Synthesis 1998, 1467). The amides 21 are obtained by coupling the carboxylic acid with the appropriate amine in the presence of DEPC or 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (EDCl). Esters 20 can also be obtained by first reacting the carboxylic acids 19 with a dibromoalkane followed by displacement of the terminal bromide with an amine (Scheme 7).
[0000]
II. Specific Compound Syntheses
[0089] Specific compounds which are representative of this invention can be prepared as per the following examples. No attempt has been made to optimize the yields obtained in these reactions. Based on the following, however, one skilled in the art would know how to increase yields through routine variations in reaction times, temperatures, solvents and/or reagents.
[0090] The products of certain syntheses can be used as intermediates to produce more than one of the instant compounds. In those cases, the choice of intermediates to be used to produce compounds of the present invention is a matter of discretion that is well within the capabilities of those skilled in the art.
Example 1
Synthesis of Benzylidene 4 (R 2 =2-furyl, R 3a ═F, R 3b , R 3d ═H)
[0091] A mixture of 3 (3.0 g, 11.69 mmol) and 2-furaldehyde (1.17 g, 12.17 mmol) in 75 mL of ethanol and 3 mL of concentrated hydrogen chloride was allowed to stir at reflux for 16 hours. The reaction was then cooled to room temperature, and the resulting precipitate was filtered off, washed with ethanol, diethyl ether, and air dried to afford 1.27 g (45%) of product.
Example 2
Synthesis of Indenopyrimidine 1 (R 2 =2-furyl, R 3a ═F, R 3b , R 3c , R 3d ═H)
[0092] A mixture of 4 (0.5 g, 2.06 mmol), guanidine carbonate (0.93 g, 5.16 mmol), and 20.6 mL of 0.5 M sodium methoxide in methanol was stirred at reflux for 16 hours. The reaction mixture was cooled to room temperature, and diluted with water. The resulting precipitate was collected, washed with water, ethanol, diethyl ether, and then dried. Crude material was then purified over silica gel to afford 0.024 g (4%) of product. MS m/z 282.0 (M+H).
Example 3
Synthesis of 2-Amino-4-methanesulfonyl-indeno[1,2-d]pyrimidin-5-one
[0093] To a suspension of 5 (Augustin, M.; Groth, C.; Kristen, H.; Peseke, K.; Wiechmann, C. J. Prakt. Chem. 1979, 321, 205) (1.97 g, 8.10 mmol) in MeOH (150 mL) was added a solution of oxone (14.94 g, 24.3 mmol) in H 2 O (100 mL). The mixture was stirred at room temperature overnight then diluted with cold H 2 O (500 mL), made basic with K 2 CO 3 and filtered. The product was washed with water and ether to give 0.88 g (40%) of sulfone 6. MS m/z 297.9 (M+Na).
Example 4
Synthesis of Aminopyrimidine 7 (R 2 ═NHPh, R 3 ═H)
[0094] A mixture of sulfone 6 (0.20 g, 0.73 mmol) and aniline (0.20 g, 2.19 mmol) in N-methylpyrrolidinone (3.5 mL) was heated to 100° C. for 90 minutes. After cooling to room temperature, the mixture was diluted with EtOAc (100 mL), washed with brine (2×75 mL) and water (2×75 mL), and dried over Na 2 SO 4 . After filtration and concentration in vacuo, the residue was purified by column chromatography eluting with 0-50% EtOAc in hexane to yield 0.0883 g (42%) of product 7. MS m/z 289.0 (M+H).
Example 5
Synthesis of Phthalate Ester 8
[0095] A 1.37 M hexanes solution of n-BuLi (53.6 mL, 73.4 mmol) was added to a cold, −78° C., THF solution (100 mL) of furan (5.3 mL, 73.4 mmol) and the reaction was then warmed to 0° C. After 1.25 h at 0° C. neat allyl bromide (7.9 mL, 91.8 mmol) was added in one portion. After 1 h at 0° C., saturated aqueous NH 4 Cl was added and the layers were separated. The aqueous phase was extracted with EtOAc and the combined organics were washed with water and brine, dried over Na 2 SO 4 , and concentrated to give 4.6 g (58%) of 2-allylfuran which was used without further purification.
[0096] The crude allyl furan (4.6 g, 42.6 mmol) and dimethylacetylene dicarboxylate (5.2 mL, 42.6 mmol) were heated to 90° C. in a sealed tube without solvent. After 6 h at 90° C. the material was cooled and purified by column chromatography eluting with 25% EtOAc in hexanes to give 5.8 g (54%) of the oxabicycle as a yellow oil. MS m/z 251 (M+H).
[0097] Tetrahydrofuran (60 mL) was added dropwise to neat TiCl 4 (16.5 mL, 150.8 mmol) at 0° C. A 1.0 M THF solution of LiAlH 4 (60.3 mL, 60.3 mmol) was added dropwise, changing the color of the suspension from yellow to a dark green or black suspension. Triethylamine (2.9 mL, 20.9 mmol) was added and the mixture was refluxed at 75-80° C. After 45 min, the solution was cooled to rt and a THF solution (23 mL) of the oxabicycle (5.8 g, 23.2 mmol) was added to the dark solution. After 2.5 h at rt, the solution was poured into a 20% aq. K 2 CO 3 solution (200 mL) and the resulting suspension was filtered. The precipitate was washed several times with CH 2 Cl 2 and the filtrate layers were separated. The aqueous phase was extracted with CH 2 Cl 2 and the combined organics were washed with water and brine, dried over Na 2 SO 4 , concentrated, and purified by column chromatography eluting with 25% EtOAc in hexanes to give 3.5 g (64%) of the phthalate ester 8 as a yellow oil. MS m/z 235 (M+H).
Example 6
Synthesis of Indanedione 9
[0098] A 60% dispersion of sodium hydride in mineral oil (641 mg, 16.0 mmol) was added to an EtOAc solution (3.5 mL) of the phthalate ester 8 (2.5 g, 10.7 mmol), and the resulting slurry was refluxed. After 1 h the solution became viscous so an additional 7.5 mL of EtOAc was added. After 4 h at reflux the suspension was cooled to rt and filtered to give a yellow solid. This solid was added portionwise to a solution of HCl (25 mL water and 5 mL conc. HCl) at 80° C. The suspension was heated for an additional 30 min at 80° C., cooled to rt, and filtered to give 1.2 g (60%) of the indanedione 9 as a yellow solid. MS m/z 187 (M+H).
Example 7
Synthesis of Dimethylketene Dithioacetal 10
[0099] Solid potassium fluoride (7.5 g, 129.1 mmol) was added to a 0° C. solution of indanedione 9 (1.2 g, 6.5 mmol) and CS 2 (0.47 mL, 7.8 mmol) in DMF (10 mL). The cold bath was removed and after 30 min neat iodomethane (1.00 mL, 16.3 mmol) was added. After 5 h at rt, the suspension was diluted with EtOAc and then washed with water and brine. The organic layer was dried over Na 2 SO 4 , concentrated, and purified by column chromatography eluting with 20% EtOAc in hexanes to give 1.4 g (75%) of the dimethylketene dithioacetal 10 as a yellow solid. MS m/z 291 (M+H).
Example 8
Synthesis of Pyrimidine 11 (R 2 =Ph, R 3a ═CHCHCH3, R 3d ═H)
[0100] A 2.0 M solution of PhMgCl in THF (13 mL, 25.7 mmol) was added to a −78° C. solution of dimethylketene dithioacetal 10 (5.7 g, 19.8 mmol) in 200 mL of THF. After 3 h at −78° C., saturated aqueous NH 4 Cl was added and the layers were separated. The aqueous layer was extracted with EtOAc and the combined organic extracts were washed with water and brine, dried over Na 2 SO 4 , concentrated, and purified by column chromatography eluting with 20% EtOAc in hexanes to give 4.9 g (77%) of the thioenol ether as a yellow solid. MS m/z 321 (M+H).
[0101] Solid guanidine hydrochloride (1.5 g, 15.3 mmol) was added to a solution of the thioenol ether (4.9 g, 15.3 mmol) and K 2 CO 3 (2.6 g, 19.1 mmol) in 30 mL of DMF and the solution was heated to 80° C. After 6 h at 80° C., the solution was diluted with EtOAc and washed with water and brine. The organic layer was dried over Na 2 SO 4 , concentrated, and purified by column chromatography eluting with 40% EtOAc in hexanes to give 4.6 g (96%) of the pyrimidine regioisomers 11 as yellow solids. MS m/z 314 (M+H).
Example 9
Synthesis of Aldehyde 13 (R 2 =Ph)
[0102] Solid MeSO 2 NH 2 (277 mg, 2.9 mmol) was added to a t-BuOH:H 2 O (1:1) solution (30 mL) of AD-mix-α (4.0 g). The resulting yellow solution was added to an EtOAc solution (15 mL) of the pyrimidine (910 mg, 2.9 mmol). After 3 days, solid sodium sulfite (4.4 g, 34.9 mmol) was added. After stirring for 1.5 h, the heterogeneous solution was diluted with EtOAc and the layers were separated. The aqueous phase was extracted with EtOAc and the combined extracts were washed with water and brine, dried over Na 2 SO 4 , concentrated, and purified by column chromatography eluting with 100% EtOAc to give 710 mg (70%) of the intermediate diol 12. MS m/z 348 (M+H).
[0103] Solid HIO 4 -2H 2 O (933 mg, 4.1 mmol) was added to a 0° C. solution of diol 12 (710 mg, 2.1 mmol) in THF. After 1.5 h at 0° C., the solution was diluted with EtOAc and the organic phase was washed with saturated aqueous NaHCO 3 , water, and brine. The organic layer was dried over Na 2 SO 4 and concentrated to give 603 mg (98%) of aldehyde 13 as a yellow solid that was used without further purification. MS m/z 302 (M+H).
Example 10
Synthesis of Amine 14 via Reductive Amination (R 3a ═N(—CH 2 CH 2 OCH 2 CH 2 —)
[0104] Solid NaBH(OAc) 3 (53 mg, 0.25 mmol) was added to a solution of aldehyde 13 (50 mg, 0.17 mmol), morpholine (0.034 mL, 0.34 mmol), and AcOH (0.014 mL, 0.25 mmol) in 1 mL of THF. After 3 d the solution was filtered and concentrated. The resulting material was dissolved in CH 2 Cl 2 and washed with saturated aqueous NaHCO 3 and brine, dried over Na 2 SO 4 , concentrated, and purified by column chromatography eluting with 0-10% MeOH in CH 2 Cl 2 to give 38 mg (60%) of the amine 14 as a yellow solid. MS m/z 373 (M+H). The product was dissolved in a minimum amount of CH 2 Cl 2 and treated with 1.0 M HCl in ether to obtain the hydrochloride salt.
Example 11
Cyclization to Form Dihydropyridine 16 (R 2 =2-furyl, R 3 ═H)
[0105] To a solution of 3-dicyanovinylindan-1-one (4.06 g, 20.9 mmol) in 200 mL of ethanol was added 2-furaldehyde (3.01 g, 31.4 mmol) and 25 mL of conc. NH 4 OH. The solution was heated to reflux for 2 h and allowed to cool to rt overnight. The mixture was concentrated in vacuo to remove ethanol. The residue was filtered and washed with water. The purple solid obtained was dried to yield 5.92 g (89%). MS m/z 290 (M + +1).
Example 12
Oxidation of Dihydropyridine 16 to Pyridine 17 (R 2 =2-furyl, R 3 ═H, R 4 ═NH 2 , R 5 ═CN, X═O)
[0106] To a refluxing solution of dihydropyridine 16 (5.92 g, 20.4 mmol) in acetic acid (100 mL) was added a solution of chromium (VI) oxide (2.05 g, 20.4 mmol) in 12 mL of water. After 10 minutes at reflux, the reaction was diluted with water until a precipitate started to form. The mixture was cooled to room temperature and filtered. The residue was washed with water to give 4.64 g (79%) of a brown solid. MS m/z 288 (M + +1).
Example 13
Reduction of Ketone 17 to Alcohol 18 (R 2 =2-furl, R 3 ═H, R 4 ═NH, R 5 ═CN, X═H, OH)
[0107] To a 0° C. solution of ketone 17 (0.115 g, 0.40 mmol) in 12 mL of THF was added a 1.0 M LiAlH 4 solution in THF (0.40 mL, 0.40 mmol). The reaction was stirred at 0° C. for 1 h. The reaction was quenched by the addition of ethyl acetate (1.5 mL), water (1.5 mL), 10% aq. NaOH (1.5 mL), and saturated aq. NH 4 Cl (3.0 mL). The mixture was extracted with ethyl acetate (3×35 mL), washed with brine, and dried over sodium sulfate. The remaining solution was concentrated to yield 0.083 g (72%) of a yellow solid. MS m/z 290 (M + +1).
Example 14
Hydrolysis of Nitrile 17 to Carboxylic Acid 19 (R 2 =2-furyl, R 3 ═H, R 4 ═NH 2 , R 5 ═COOH, X═O)
[0108] To a mixture of nitrile 17 (0.695 g, 2.42 mmol) and ethanol (30 mL) was added 5 mL of 35% aqueous sodium hydroxide. The resulting mixture was heated to reflux overnight. After cooling to rt, the solution was poured into water and acidified with 1 N HCl. The resulting precipitate was isolated by filtration and washed with water to yield 0.623 g (84%) of a brown solid. MS m/z 329 (M + +23).
Example 15
Synthesis of Carboxylic Ester 20 with Silver Carbonate (R 2 =2-furyl, R 3 ═H, R 4 ═NH 2 , R 5 ═CO 2 CH 2 CH 2 NMe 2 , X═O)
[0109] A suspension of carboxylic acid 19 (5.0 g, 16.3 mmol), silver carbonate (5.8 g, 21.2 mmol), and tetrabutylammonium iodide (1.5 g, 4.1 mmol) in 80 mL of DMF was heated to 90° C. After 1 h, the mixture was cooled to rt and 2-(dimethylamino)ethylchloride hydrochloride (2.4 g, 16.3 mmol) was added and the mixture was heated to 100° C. After 7 h, the reaction was filtered while hot, concentrated and purified by column chromatography eluting with 0-10% MeOH/CH 2 Cl 2 to yield 0.160 g (3%) of a yellow solid. MS m/z 378 (M + +1). The product was dissolved in a minimum of dichloromethane and treated with 1.0 M HCl in ether to obtain the hydrochloride salt.
Example 16
Synthesis of Carboxylic Ester 20 with DEPC (R 2 =2-furyl, R 3 ═H, R 4 ═NH 2 , R 5 ═CO 2 CH 2 CH(—CH 2 CH 2 CH 2 (Me)N—), X═O)
[0110] To a mixture of carboxylic acid 19 (0.40 g, 1.3 mmol) and (S)-1-methyl-2-pyrrolidinemethanol (0.50 mL, 3.9 mmol) in DMF (30 mL) was added 0.20 mL (1.3 mmol) of diethylphosphoryl cyanide and triethylamine (0.20 mL, 1.3 mmol). The reaction was stirred at 0° C. for one hour and then heated up to approximately 70° C. overnight. The reaction was then cooled to rt and diluted with ethyl acetate. The organic mixture was washed with saturated aqueous NaHCO 3 , water, and brine. After being dried with sodium sulfate, the solution was concentrated. The residue was purified by column chromatography eluting with 10-100% ethyl acetate in hexane and then preparative TLC eluting with 2% MeOH in dichloromethane to yield 1.9 mg (0.4%) of a yellow solid. MS m/z 404 (M + +1).
Example 17
Synthesis of Carboxylic Amide 21 with DEPC (R 2 =2-furyl, R 3 ═H, R 4 ═NH, R 5 ═CO 2 CH 2 CH(—CH 2 CH 2 CH 2 (Me)N—), X═O)
[0111] To a mixture of carboxylic acid 19 (0.25 g, 0.82 mmol) and N,N,N′-trimethylethylenediamine (0.14 mL, 1.08 mmol) in DMF (20 mL) was added 0.12 mL (0.82 mmol) of diethylphosphoryl cyanide and triethylamine (0.11 mL, 0.82 mmol). The reaction was stirred at 0° C. for one hour and then heated up to approximately 60° C. overnight. The reaction was then cooled to rt and diluted with ethyl acetate. The organic mixture was washed with saturated aqueous NaHCO 3 , water, and brine. After being dried with magnesium sulfate, the solution was concentrated. The residue was purified by column chromatography eluting with 0-10% methanol in dichloromethane and then preparative TLC eluting with 1% MeOH in dichloromethane to yield 3.3 mg (10%) of a yellow solid. MS m/z 391 (M + +1). The product was dissolved in a minimum of diethyl ether and treated with 1.0 M HCl in ether to obtain the hydrochloride salt.
Example 18
Synthesis of Carboxylic Amide 21 with EDCl (R 2 =2-furyl, R 3 ═H, R 4 ═CON(—CH 2 CH 2 NMeCH 2 CH 2 —), X═O)
[0112] A mixture of carboxylic acid 19 (0.300 g, 0.979 mmol), N-methylpiperazine (0.295 g, 2.94 mmol), 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (0.563 g, 2.94 mmol) 1-hydroxybenzotriazole hydrate (0.397 g, 2.94 mmol), triethylamine (0.298 g, 2.94 mmol) in DMF (8 mL) was stirred at rt overnight. The mixture was then diluted with water and extracted several times with ethyl acetate. The combined organics were washed twice with brine and then dried over sodium sulfate. The solution was concentrated and then purified by column chromatography to afford 0.092 g (2%) of solid. MS m/z 389 (M + +1). The product was treated with 1.0 M HCl in ether to obtain the hydrochloride salt.
Example 19
Synthesis of Carboxylic Ester 20 via a dibromoalkane (R 2 =Ph, R 3 ═H, R 4 ═NH 2 , R 5 ═CO 2 CH 2 CH 2 CH 2 NMe 2 , X═O)
[0113] To a solution of carboxylic acid 19 (0.100 g, 0.32 mmol) in DMF (1.5 mL) was added 60% NaH dispersion in mineral oil (0.013 g, 0.32 mmol). After 10 min at rt, 1,3-dibromopropane (0.035 mL, 0.35 mmol) was added and the solution was stirred at rt for 17 h. After concentration, the residue was purified via column chromatography eluting with 40% ethyl acetate in hexanes to yield 0.014 g (9%) of a yellow solid. MS m/z 437 (M + +1).
[0114] To a solution of the yellow solid (0.014 mg, 0.03 mmol) in a sealed tube was added a 40% aqueous solution of dimethylamine (0.5 mL, 3.0 mmol). The tube was heated to 75° C. for 2 h before concentrating. The residue was purified by column chromatography eluting with 0-10% methanol in dichloromethane to yield 0.009 g (70%) of a yellow solid. MS m/z 402 (M + +1). The product was dissolved in a minimal amount of CH 2 Cl 2 and treated with 1 N HCl in ether to obtain the hydrochloride salt.
[0115] Following the general synthetic procedures outlined above and in Examples 1-19, the compounds of Table 1 below were prepared.
[0000]
TABLE 1
MS
No.
R 2
R 3a
R 3b
R 3c
R 3d
R 4
X
(M + 1)
1
4-MeOPh
H
H
H
H
NH 2
CH 2
290
2
4-MeOPh
H
H
H
H
NH 2
CO
304
3
2-furyl
H
H
H
H
NH 2
CO
264
4
2-furyl
H
H
H
H
NH 2
CH 2
250
5
3-pyridyl
H
H
H
H
NH 2
CO
297
(+Na)
6
4-pyridyl
H
H
H
H
NH 2
CO
275
7
H
H
H
H
NH 2
CO
281
8
4-ClC 6 H 4
H
H
H
H
NH 2
CO
308
9
3-NO 2 C 6 H 4
H
H
H
H
NH 2
CO
319
10
Ph
H
H
H
H
NH 2
CO
274
11
3-MeOC 6 H 4
H
H
H
H
NH 2
CO
304
12
2-MeOC 6 H 4
H
H
H
H
NH 2
CO
304
13
3-HOC 6 H 4
H
H
H
H
NH 2
CO
290
14
2-thiophenyl
H
H
H
H
NH 2
CO
302
15
3-thiophenyl
H
H
H
H
NH 2
CO
302
16
2-furyl
H
Br
H
H
NH 2
CO
342
17
2-furyl
OH
H
H
H
NH 2
CO
280
18
SCH3
NH 2
H
H
H
NH 2
CO
259
19
3-FC 6 H 4
H
H
H
H
NCHNMe 2
CO
347
20
2-furyl
NH 2
H
H
H
NH 2
CO
279
21
2-furyl
H
H
H
NH 2
NH 2
CO
279
22
2-furyl
H
CF 3
H
H
NH 2
CO
332
23
2-furyl
H
H
CF 3
H
NH 2
CO
332
24
Ph
H
H
H
H
NHMe
CO
288
25
2-furyl
H
Cl
Cl
H
NH 2
CO
332
26
2-furyl
Cl
H
H
Cl
NH 2
CO
332
27
Ph
H
H
H
H
N(CH 2 ) 2 NEt 2
CO
373
28
3,4-F 2 C 6 H 3
H
H
H
H
NH 2
CO
310
29
3,5-F 2 C 6 H 3
H
H
H
H
NH 2
CO
310
30
H
H
H
H
NH 2
CO
305
31
3,4,5-F 3 C 2 H 2
H
H
H
H
NH 2
CO
340
(M + Na)
32
Ph
H
H
H
NH 2
CO
348
33
Ph
H
H
H
NH 2
CO
348
34
H
H
H
H
NH 2
CO
333
35
2-furyl
H
H
Br
H
NH 2
CO
342/344
36
2-furyl
H
H
H
F
NH 2
CO
282
37
2-furyl
MeO
H
H
H
NH 2
CO
294
38
4-FC 6 H 4
H
H
H
H
NH 2
CO
292
39
3-FC 6 H 4
H
H
H
H
NH 2
CO
292
40
SO 2 Me
H
H
H
H
NH 2
CO
298
41
Sme
H
H
H
H
NH 2
CO
266
42
Ome
H
H
H
H
NH 2
CO
477
(2M + Na)
43
NHPh
H
H
H
H
NH 2
CO
289
44
3-furyl
H
H
H
H
NH 2
CO
264
45
5-methyl-2-furyl
H
H
H
H
NH 2
CO
278
46
2-furyl
OCH 2 CH 2 NHCO 2 tBu
H
H
H
NH 2
CO
437
47
Ph
H
H
H
H
Me
CO
297
48
Ph
H
H
H
H
OMe
CO
291
49
Ph
CH 2 NMeCH 2 CH 2 NMe 2
H
H
H
NH 2
CO
388
50
Ph
H
H
H
NH 2
CO
386
51
Ph
H
H
H
NH 2
CO
373
52
Ph
CH 2 NEt 2
H
H
H
NH 2
CO
359
53
Ph
H
H
H
NH 2
CO
371
54
Ph
H
H
H
NH 2
CO
429
55
Ph
H
H
H
NH 2
CO
443
56
Ph
CH 2 NMeCH 2 CO 2 Me
H
H
H
NH 2
CO
389
57
Ph
H
H
H
NH 2
CO
401
58
Ph
H
H
H
NH 2
CO
416
59
Ph
H
H
H
NH 2
CO
414
60
Ph
H
H
H
NH 2
CO
486
61
Ph
H
H
H
NH 2
CO
422
62
Ph
H
H
H
NH 2
CO
397
[0000]
TABLE 2
MS
No.
X
R 2
R 3a
R 3b
R 3c
R 3d
R 1
(M + 1)
63
CO
2-furyl
H
H
H
H
CN
288
64
CO
Ph
H
H
H
H
CN
298
65
CO
Ph
H
H
H
H
COOH
315
(M − 1)
66
CO
3-furyl
H
H
H
H
CN
288
67
CO
3-FC 6 H 4
H
H
H
H
CN
316
68
CO
3-pyridyl
H
H
H
H
CN
299
69
CO
2-furyl
H
H
H
H
COOH
305
(M − 1)
70
CO
2-furyl
H
H
H
H
CO 2 CH 2 CH 2 NMe 2
378
71
CO
4-FC 6 H 4
H
H
H
H
CN
316
72
CO
2-thiophenyl
H
H
H
H
CN
304
73
CO
3-thiophenyl
H
H
H
H
CN
304
74
CO
3-MeOC 6 H 4
H
H
H
H
CN
328
75
CO
2-imidazolyl
H
H
H
H
CN
288
76
CO
2-furyl
H
H
H
H
CONHCH 2 CH 2 NMe 2
377
77
CO
2-furyl
H
H
H
H
CONMeCH 2 CH 2 NMe 2
391
78
CO
2-furyl
H
H
H
H
CONHCHMeCH 2 NMe 2
391
79
CO
2-furyl
F
F
F
F
CN
358
(M − 1)
80
CO
2-furyl
H
H
H
H
389
81
CO
Ph
H
H
H
H
CO 2 CH 2 CH 2 NMe 2
388
82
CO
2-furyl
H
H
H
H
404
83
CO
Ph
H
H
H
H
457
84
CO
Ph
H
H
H
H
444
85
CO
Et
H
H
H
H
CN
250
86
CO
i-Bu
H
H
H
H
CN
278
87
CO
Ph
H
H
H
H
CO 2 CH 2 CH 2 CH 2 NMe 2
402
88
CO
Ph
H
H
H
H
414
89
CHOH
2-furyl
H
H
H
H
CN
290
90
CO
Ph
H
H
H
H
414
91
CO
Ph
H
H
H
H
430
92
CO
Ph
H
H
H
H
CO 2 CH 2 CHMeCH 2 NMe 2
416
93
CO
3-thiophenyl
H
H
H
H
CO 2 CH 2 CH 2 NMe 2
394
94
CO
CH 2 CH 2 CHCH 2
H
H
H
H
CN
276
95
CO
c-Hex
H
H
H
H
CN
302
(M − 1)
96
CO
2-furyl
H
H
H
H
(S)—CO 2 CHMeCH 2 NMe 2
392
III. Biological Assays and Activity
Ligand Binding Assay for Adenosine A2a Receptor
[0116] Ligand binding assay of adenosine A2a receptor was performed using plasma membrane of HEK293 cells containing human A2a adenosine receptor (PerkinElmer, RB-HA2a) and radioligand [ 3 H]CGS21680 (PerkinElmer, NET1021). Assay was set up in 96-well polypropylene plate in total volume of 200 μL by sequentially adding 20 μL1:20 diluted membrane, 130 μL assay buffer (50 mM Tris.HCl, pH7.4 10 mM MgCl 2 , 1 mM EDTA) containing [ 3 H] CGS21680, 50 μL diluted compound (4×) or vehicle control in assay buffer. Nonspecific binding was determined by 80 mM NECA. Reaction was carried out at room temperature for 2 hours before filtering through 96-well GF/C filter plate pre-soaked in 50 mM Tris.HCl, pH7.4 containing 0.3% polyethylenimine. Plates were then washed 5 times with cold 50 mM Tris.HCl, pH7.4, dried and sealed at the bottom. Microscintillation fluid 30 μl was added to each well and the top sealed. Plates were counted on Packard Topcount for [ 3 H]. Data was analyzed in Microsoft Excel and GraphPad Prism programs. (Varani, K.; Gessi, S.; Dalpiaz, A.; Borea, P. A. British Journal of Pharmacology, 1996, 117, 1693)
Adenosine A2a Receptor Functional Assay
[0117] CHO-K1 cells overexpressing human adenosine A2a receptors and containing cAMP-inducible beta-galactosidase reporter gene were seeded at 40-50K/well into 96-well tissue culture plates and cultured for two days. On assay day, cells were washed once with 200 μL assay medium (F-12 nutrient mixture/0.1% BSA). For agonist assay, adenosine A2a receptor agonist NECA was subsequently added and cell incubated at 37° C., 5% CO 2 for 5 hrs before stopping reaction. In the case of antagonist assay, cells were incubated with antagonists for 5 minutes at R.T. followed by addition of 50 nM NECA. Cells were then incubated at 37° C., 5% CO 2 for 5 hrs before stopping experiments by washing cells with PBS twice. 50 μL 1× lysis buffer (Promega, 5× stock solution, needs to be diluted to 1× before use) was added to each well and plates frozen at −20° C. For β-galactosidase enzyme colorimetric assay, plates were thawed out at room temperature and 50 μL 2× assay buffer (Promega) added to each well. Color was allowed to develop at 37° C. for 1 h or until reasonable signal appeared. Reaction was then stopped with 150 μL 1M sodium carbonate. Plates were counted at 405 nm on Vmax Machine (Molecular Devices). Data was analyzed in Microsoft Excel and GraphPad Prism programs. (Chen, W. B.; Shields, T. S.; Cone, R. D. Analytical Biochemistry, 1995, 226, 349; Stiles, G. Journal of Biological Chemistry, 1992, 267, 6451)
[0000] Haloperidol-Induced Catalepsy Study in C57bl/6 Mice
[0118] Mature male C57bl/6 mice (9-12 week old from ACE) were housed two per cage in a rodent room. Room temperature was maintained at 64-79 degrees and humidity at 30-70% and room lighting at 12 hrs light/12 hrs dark cycle. On the study day, mice were transferred to the study room. The mice were injected subcutaneously with haloperidol (Sigma H1512, 1.0 mg/ml made in 0.3% tartaric acid, then diluted to 0.2 mg/ml with saline) or vehicle at 1.5 mg/kg, 7.5 ml/kg. The mice were then placed in their home cages with access to water and food. 30 minutes later, the mice were orally dosed with vehicle (0.3% Tween 80 in saline) or compounds at 10 mg/kg, 10 ml/kg (compounds, 1 mg/ml, made in 0.3% Tween 80 in saline, sonicated to obtain a uniform suspension). The mice were then placed in their home cages with access to water and food. 1 hour after oral dose, the catalepsy test was performed. A vertical metal-wire grid (1.0 cm squares) was used for the test. The mice were placed on the grid and given a few seconds to settle down and their immobility time was recorded until the mice moved their back paw(s). The mice were removed gently from the grid and put back on the grid and their immobility time was counted again. The measurement was repeated three times. The average of three measurements was used for data analysis.
[0119] Compound 70 showed 87% inhibition and compound 3 showed 90% inhibition of haloperidol-induced catalepsy when orally dosed at 10 mg/kg.
[0000]
TABLE 5
Ki (nM)
A2a
A1
A2a
antagonist
antagonist
No.
binding
function
function
1
44.64
233.7
52.98
2
2.032
6.868
5.32
3
0.26
0.0066
0.288
4
0.885
2.63
15.57
5
5.355
9.64
27.1
6
3.9
4.56
16.44
7
0.26
0.49
6.89
8
58.41
5.5
11.59
9
20.82
4.85
7.69
10
6.1
0.109
1.2
11
8.85
1.63
2.47
12
33.49
32.52
172.3
13
5.16
35.59
10.35
14
2.19
0.59
3.19
15
3.23
0.258
3.46
16
1.75
0.169
5.22
17
6.3
67.14
111.29
18
317.95
>3000
188.99
19
110.73
20.88
21.64
20
0.05
0.126
0.91
21
0.376
0.053
3.51
22
14.16
0.055
2.75
23
13.58
0.55
1.47
24
30.32
>3000
5.99
25
172.85
5.69
17.44
26
34.57
0.88
3.13
27
146.84
68.28
>1000
28
48.9
3.53
5.86
29
20.95
1.42
4.27
30
31.55
10.15
4.05
31
140.68
15.22
17.5
32
3.55
0.634
9.89
33
0.175
0.34
0.021
34
560.13
35
3.49
0.265
7.09
36
4.37
0.052
2.52
37
2.86
0.143
3.07
38
2.34
0.956
9.44
39
4.92
0.926
2.31
40
2720.46
41
88.01
575.43
>3000
42
118.2
782.18
>10000
43
39.9
3.68
2.34
44
3.93
0.208
7.4
45
4.013
0.005
0.016
46
60.56
490.14
32.54
47
1076.76
48
470.84
>1000
>1000
49
51.12
40.13
119.03
50
80.15
11.31
94.24
51
36.81
3.26
32.92
52
94.41
18.33
107.17
53
64.15
14.25
40.82
54
40.79
3.19
19.56
55
32.82
5.84
19.86
56
25.72
6.81
25.76
57
34.02
15.93
39.29
58
30.65
11.65
60.99
59
40.79
7.94
34.11
60
34.29
61
29.83
62
58.39
63
0.59
0.0002
0.18
64
13.09
0.138
4.61
65
574.71
244.96
163.36
66
4.21
0.069
15.59
67
13.4
0.618
4.37
68
7.59
0.73
34.84
69
2261
90.16
>1000
70
9.89
0.44
20.13
71
17.24
3.39
2.42
72
12.64
2.54
6.24
73
4.925
0.06
9.7
74
14.67
5.7
7.28
75
23.72
1.51
78.33
76
33.03
22.13
>500
77
6.254
0.68
>500
78
17.65
1.58
>500
79
8.03
12.48
>1000
80
69.08
15.86
55.99
81
228.7
29.03
33.63
82
20.24
1.36
29.58
83
200.06
74.87
117.05
84
173.98
24.71
27.42
85
507.72
86
244.07
>1000
39.26
87
98.93
39.45
>300
88
129.6
48.87
>300
89
5.85
1.12
11.16
90
202.17
57.7
>300
91
208.32
22.07
14.67
92
38.82
13.9
32.88
93
64.05
23.57
104.31
94
49.55
>1000
35.99
95
338.13
>1000
110.22
96
48.55
10.08
52.45 | This invention provides novel arylindenopyridines and arylindenopyrimidines of the formula:
wherein R 1 , R 2 , R 3 , R 4 , and X are as defined above, and pharmaceutical compositions comprising same, useful for treating disorders ameliorated by antagonizing adenosine A2a receptors. This invention also provides therapeutic and prophylactic methods using the instant compounds and pharmaceutical compositions. | 2 |
BACKGROUND OF THE INVENTION
This invention relates to a method and apparatus for vapor phase deposition, more particularly to a method and apparatus for vapor phase deposition under low pressure using a horizontal type reaction tube in which a large number of semiconductor substrates are arranged in parallel and transversely to the longitudinal axis of the tube.
Many types of vapor phase deposition systems such as horizontal, vertical and barrel types, are known in the art. Vertical and barrel type systems, however, are relatively poor in productivity since only a small number of wafers can be loaded therein. Horizontal type systems, i.e., systems having a horizontal reaction tube, are preferable since a large number of wafers can be loaded therein by arranging them in the tube in parallel and transversely to the longitudinal axis of the tube.
Horizontal type systems in which wafers are arranged in parallel and transversely to the axis of the reaction tube (referred to hereon as "horizontal type systems"), however, cannot be easily applied to epitaxial growth of impurity-doped single crystalline films since such applications require strict film thickness specific resistivity, and other conditions.
In the reaction tube of the horizontal type system, for example, silicon source and impurity gases progressively decrease in concentration from the inlet toward the outlet due to their consumption. This causes a corresponding progressive decrease in the thickness and doping concentration of the deposited film. This in turn causes a corresponding increase in the specific resistivity of the film. Provision of a temperature gradient increasing from the inlet toward the outlet along the axis of the tube can give the thickness of the deposited films uniformity in spite of the progressive decrease in the concentration of the reaction gas. However, it also causes reduction in impurity concentration from the inlet toward the outlet. The resultant films therefore have different thicknesses and/or impurity concentrations, i.e., specific resistivities. Thus, only a small number of the products can meet the strict requirements of thickness and specific resistivity.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide a horizontal type vapor phase deposition system which can produce a large number of epitaxial films with excellent uniformity in both film thickness and impurity concentration.
The above object is attained by providing a method of vapor phase deposition for growing a semiconductor layer on a plurality of wafers, wherein a main gas, comprising a reaction gas and a impurity gas flows in a first direction through a deposition region in a reaction tube. The plurality of wafers are arranged in the deposition region so that each of the major surfaces of the plurality of wafers in parallel to the others and is transverse to a longitudinal axis of the reaction tube. An auxiliary gas comprising an impurity gas is introduced into the reaction tube at a position downstream of the deposition region in such a manner that the impurity gas of the auxiliary gas diffuses in a second direction opposite to the first direction along an inner wall of the reaction tube.
This invention is based on the discovery that a gas fed to a reaction tube near a discharge port can diffuse toward a gas inlet along the inner stagnant layer in spite of gas suction toward the discharge port and the gas flow from the gas inlet toward the discharge port. Such reverse diffusion occurs more easily in a lower pressure. The reverse diffusion effectively makes up for the decreased gas concentration only when the decreased gas ratio as considerably low compared with the other gas ratios. These conditions are well satisfied in the case of vapor phase epitaxial growth under low pressure. It is also preferred that the impurity gas of the auxiliary gas be diffused in a reverse direction since its concentration is very low.
Further, it is preferable to guide the auxiliary gas along the inner wall of the reaction tube since the velocity of the main gas flow from the gas inlet toward the gas outlet in the reaction tube is very slow there. Such guidance is preferably assisted by use of an inner tube, inserted inside the reaction tube, having openings distributed along the axis of the tube.
According to this invention, there is also provided an apparatus for vapor phase deposition of a semiconductor film on a plurality of wafers comprising: (a) a reaction tube having a deposition region in which said plurality of wafers are so arranged that each of the major surfaces of the plurality of wafers is parallel to the others and is transverse to a longitudinal axis of the reaction tube; (b) means for heating the wafers; (c) means for flowing a main gas in a first direction through the deposition region in the reaction tube; and (d) means arranged downstream of the deposition region, for introducing an auxiliary gas into the reaction tube in such a manner that the auxiliary gas diffuses along an inner wall of the reaction tube in a second direction opposite to the first direction.
It is preferred that the apparatus further comprise means for guiding the auxiliary gas along the inner wall of the reaction tube. The guiding means may be a tubular member extending inside the reaction tube in the second direction.
It is also preferred that the reaction tube comprise an outer tube and an inner tube surrounded by the outer tube and removable from the reaction tube so that matter deposited on the inner wall of the inner tube can be easily cleaned off. It is further preferred that the inner tube have a plurality of openings distributed along the longitudinal axis of the inner tube, and the inner tube and the outer tube form therebetween an annular space into which the auxiliary gas is fed. The openings provided on the inner tube may be of a shape elongated along the side of the inner tube and may be staggered along the axis of the inner tube. Alternatively, a plurality of inner tubes may be arranged along the axis of the reaction tube with the spaces therebetween defining annular openings.
Preferred embodiments of the present invention are described below by way of example with reference to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic representation of a first preferred embodiment of the apparatus for the present invention;
FIG. 2 is a sectional view of a susceptor used in the apparatus in FIG. 1;
FIG. 3 is a graph of the thickness and specific resistivity of deposited film obtained by the apparatus in FIG. 1 vs the position in the reaction tube;
FIG. 4 is schematic representation of a second preferred embodiment of an apparatus for the present invention;
FIG. 5 is a perspective view of an inner tube of a reaction tube;
FIG. 6 is a graph of the thickness and specific resistivity of deposited films obtained by the apparatus in FIG. 4 vs the position in the reaction tube; and
FIG. 7 is a graph of film thickness vs the position in the reaction tube in an experiment proving the diffusion action in the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The method according to the present invention was tested by using a vapor phase deposition apparatus as illustrated in FIG. 1. The apparatus in FIG. 1 comprises a reaction tube, comprising a 230 mmφ(230 millimeters in diameter) quartz tube 2 and 200 mmφ quartz inner tube 4 concentrically inserted therein, stainless steel inlet member 6, and stainless steel outlet member 8. Inlet member 6 has annular chamber 10 having at least three 10 mmφ-bores distributed in the inner wall thereof. Chamber 10 is connected to inlet pipe 12. Outlet member 8 has a discharge port 14. The apparatus further comprises, at the end of reaction tube 2 near outlet port 14, as auxiliary gas inlet 16 and an annular chamber 18 having twenty 5 mmφ-bores distributed in the inner wall thereof. Inside annular chamber 18 there is provided annular guide member 20 having a diameter of 180 mm for the guiding auxiliary gas along the inner wall of inner tube 4.
Twenty-one susceptors 22, each holding two silicon wafers 24 as shown in FIG. 2, where inserted in inner tube 4. These susceptors 22 were equally spaced over a 600 mm distance. Susceptors 22 were successively numbered from the left side (No. 1) to the discharge side (No. 21). The distance from susceptor No. 21 to annular guide member 20 was 450 mm. The silicon wafers 24 were heated by susceptor 22 which is inductively heated by work coil 26.
In the operation, a gas mixture of dichlorosilane (SiH 1 Cl 2 ), hydrogen (H 2 ) and phosphine (PH 3 ) was fed through the inlet pipe 12 and annular chamber 10 into the inner tube 4 and evacuated through discharge port 14. The gas feeding rates were 5 l/min for H 2 , 500 cm 3 /min for SiH 2 Cl 2 , and 20 cm 3 /min for H 2 containing 1 ppm-PH 3 . The pressure inside the tube was 1.0 Torr. The temperatures of the silicon wafers 24 were controlled to increase proportionally from 1025° C. at susceptor No. 1 to 1050° C. at susceptor No. 21. An auxiliary gas comprising 100 ppm-P 3 in H 2 was fed through auxiliary gas inlet 16 and annular chamber 18 at a gas feeding rate of 12 cm 3 /min for H 2 containing PH 3 . In this case the end of the annular space formed between tube 2 and inner tube 4 near inlet member 6 was closed so as not to allow auxiliary gas to flow therethrough and not to allow main gas to enter therein.
The measured thicknesses and specific resistivities of epitaxially grown silicon films on silicon wafers 24 resulting fromthe above operation are as shown in FIG. 3. FIG. 3 shows a uniformity of thickness of the epitaxial silicon films. This was due to the above-described temperature control. FIG. 3 also clearly shows a leveling effect on the specific resistivity attained by feeding an auxiliary PH 3 gas. If the auxiliary PH 3 gas were not fed, the specific, resistivity of the epitaxial silicon film would progressively increase from the lower number susceptors to the higher number susceptors. A very weak peak in the specific resistivity curve can be seen in FIG. 3. This peak, however, can be lowered by increasing the evacuating rate out of the reaction tube.
Assuming the tolerances for thickness and specific resistivity of epitaxial silicon films in most applications are +5% and ±7%, respectively, the above operation can produce 14 wafers or films having a 150 mm diameter satisfying the above requirements. In contract, vertical, horizontal, or barrel type vapor phase deposition systems in the prior art would produce only a maximum of about 10, 10, or 12 such wafers, respectively.
Next, the method according to the present invention was carried out by using a vapor phase deposition apparatus as shown in FIG. 4. This apparatus was similar to the apparatus used in the above-described test, except for the following:
(1) inner tube 4' has openings 28 distributed along the axis of the inner tube 3';
(2) annular guide member 20' has the same diameter as inner tube 4' to guide auxiliary gas into the space formed between tube 2 and inner tube 4'; and
(3) the end of the above space between tubes 2 and 4' near inlet member 6 is open, no closed completely.
The shape and arrangement of openings 28 in inner tube 4 in this work are illustrated in FIG. 5. The openings are 2 mm wide and extend 100 mm around the wall of inner tube 4'. A plurality of pairs of openings are distributed at 100 mm intervals and staggered along the axis of inner tube 4',each pair's openings are directly opposite each other.
In the operation, SiH 2 C1 2 , H 2 , and H 2 containing 1 ppm-PH 3 were fed at rates of 500 cm 3 /min, 5 l/min, and 18 cm 3 /min as the main gas and H 2 containing 10 ppm-PH 3 was fed at a rate of 16 cm 3 /min as the auxiliary gas. The pressure inside inner tube 4' was 1.0 Torr. The other conditions were the same as in the above-described operation.
The results are shown in FIG. 6. Both the specific resistivities and thicknesses of epitaxial silicon films were quite uniform. About 18 to 20 150-mm-diameter films have passed the above-mentioned criteria in this operation. An experiment was carried out as below to prove the diffusion action in this invention. The apparatus as shown in FIG. 4 was used. SiH 2 C1 2 and H 2 were fed at rates of 450 cm 3 /min and 5 l/min respectively through the auxiliary inlet pipe 16 into the reaction tube and evacuated out of discharge port 14. Inlet pipe 12 was closed. The pressure inside the reaction tube was 1.0 Torr. The susceptor arrangement and temperature profile in the reaction tube were similar to those in the above described operations.
The resultant thicknesses of the silicon films are shown in FIG. 7. If the thickness of a deposited film can be taken to be proportional to the amount of a gas flowing there, FIG. 7 shows that viscous flow gas A flows toward discharge port 16 without spreading beyond a rear part or a part near discharge port 16 of the reaction tube and that diffusion flow gas B reaches a front part or a part near inlet member 6 of the reaction tube with a monotonic decrease in the amount of the gas. It may be understood that an auxiliary impurity gas, such as PH 3 in the operation described above, flows with a concentration profile similar or related to the curve in FIG. 7 and contributes to deposition or doping. It is therefore understood that epitaxial films are doped desirably even at the rear part of the reaction tube by the presence of the auxiliary gas.
It should be noted that the auxiliary gas should be fed through relatively large bores or openings into the reaction tube so that the gas entering into the reaction tube can diffuse along the inner wall of the tube toward a main gas inlet. The gas should not be injected through a nozzle or nozzles to flow as a viscous flow. Clearly, the impurity concentration in a deposited film can be controlled by changing the concentration of the main and auxiliary impurity gases. | A plurality of wafers on which semiconductor films having a uniform thickness and specific resistivity are obtained by a horizontal type low pressure vapor phase deposition system, i.e., a system using a horizontal reaction tube, in which wafers are aligned in parallel and transverse to a longitudinal axis of the tube. A main gas is introduced from a main inlet into the reaction tube and an auxiliary gas including an impurity gas is introduced from an auxiliary inlet into the reaction tube in such a manner that the impurity gas diffuses toward the main inlet along an inner wall of the reaction tube. | 8 |
FIELD OF INVENTION
The present invention relates generally to an apparatus and method for stacking sheet-like articles, and more particularly to a device for controlling the pressure in a stack when stacking sheet-like articles such as envelopes that are continuously being fed into the stack.
BACKGROUND OF THE INVENTION
Envelope processing systems, such as mail piece processing, sorting and bar code application systems, typically include an envelope stacking apparatus at the end of the system to secure the sorted mail pieces in a stacked position to facilitate orderly removal of the processed mail pieces from the system. The stacked mail pieces are manually or automatically removed from the stack and/or bound by an operator.
One such stacking apparatus is disclosed in U.S. Pat. No. 4,955,596, commonly assigned. An envelope to be stacked, or any suitable sheet-like article, is forcibly fed on edge into a discharge magazine where it is stacked in a somewhat compressed array with other, previously fed envelopes. The envelope enters the discharge magazine via a dual stacker belt transport configuration, wherein a pair vertically juxtaposed stacker belts rotate about rollers disposed in a triangular array. The rollers each are rotatably mounted on shafts having a fixed axis.
The discharge magazine includes multiple transport belts that may have smooth surfaces, or may have track-like protrusions extending above the discharge magazine floor to engage the bottom edges of the stacked envelopes and advance the envelopes away from the stacker belts to permit the free entry of additional envelopes into the stacker region. The transport belts are activated by a stack sensor mechanism that includes a spring biased, pivotally mounted lever arm which extends through a gap between the pair of stacker belts. The tip of the lever arm contacts the last envelope to enter the stack. As the stack gets larger and the laterally applied normal force of the stacked envelopes overcomes the bias of the lever arm spring of the sensor mechanism, the lever arm trips a switch that in turn activates a drive motor connected to the transport belts to move the envelopes away from the stacker belts. This reduces the normal force or pressure exerted by the stack of envelopes on the stacker belts, and provides space for the entry of subsequent envelopes into the stack.
Although the stack sensor lever arm in the prior art apparatus contacts the last envelope in the stack, the lever arm contacts the last stacked envelope over a small plane, or sometimes a point, and is therefore highly susceptible to planar and height variations associated with the last stacked envelope. In high speed mail processing systems, a problem arises when the last envelope in the stack tilts such that the bottom edge and the top edge of the envelope no longer form a substantially vertical plane. As the stack becomes increasingly tight, accurate pressure sensing is critical to avoid jamming. Jamming occurs as a consequence of erroneous stack pressure sensing, when a tilted edge of the last stacked envelope obstructs the entrance to the stack of the next envelope to be stacked. Such problems are compounded when the stacker is used for simultaneously stacking a plurality of different sized (varying in height and thickness) envelopes.
Erroneous stack pressure sensing typically occurs where the lever arm contacts the tilted envelope at a surface or point that is tilted furthest away from the stacker belts. This surface exerts less force on the lever arm than the surface closest to the stacker belt. The lever arm's small plane or point of contact may erroneously indicate that the stack can receive more envelopes when the stack is actually too tight to properly receive another envelope without first activating the transport belts.
In view of the foregoing, an object of the present invention is to provide a high speed stacking apparatus and method that accurately senses the stack pressure of tilted articles to substantially reduce the occurrence of article jamming.
Another object of the present invention is to provide an apparatus and method that automatically and accurately senses the pressure applied by a stacked group of processed envelopes on a stacker conveying mechanism regardless of the degree of tilt of the last envelope to enter the stack, and in response thereto generates a signal to actuate an envelope transport system for advancing the documents in the stack away from the stacker conveyor means, thereby relieving the pressure on the conveying mechanism and creating space for the facile entry of additional processed envelopes into the stack.
A further object of the present invention is the provision of a sensor apparatus for a conveying belt mechanism for an envelope stacker device whereby one of the roller elements supporting the belt mechanism is on a laterally displaceable axis, whereby the axial displacement of the roller element is responsive to the force applied to the sensor apparatus by the stack of envelopes regardless of the angle of vertical orientation of the envelopes in the stack as the envelopes engage the sensor apparatus.
Yet another object of the present invention is the provision of an automatically actuated kicker mechanism that senses the trailing edge of an envelope entering the stack, and kicks the trailing edge away from the conveyor belts and onto an auger which drives the envelope's tracking edge outward to cooperate with the stack pressure sensor and control device to ensure that space is provided in the stack to permit subsequent envelopes to be fed into the stack without jamming.
SUMMARY OF THE INVENTION
The above objects and advantages are provided by the apparatus and method for stacking sheet-like articles disclosed herein. The invention includes an envelope conveying apparatus for stacking a series of sequentially fed sheet-like envelopes. The apparatus includes an elastic stacker belt assembly, one element of which comprises a movable roller element forming part of the conveying means, such as a spring biased roller, for sensing a force exerted by the stack of articles on the envelope conveying apparatus.
One embodiment of the invention comprises an envelope conveying apparatus having a dual belt system which extends around a portion of the moveable sensing roller and feeds the envelopes directly and sequentially into the stack. The moveable sensing roller also varies the tension of the conveying belts as a function of the force exerted by the stack of articles on the stacker belt system.
This embodiment of the invention includes a moveable dual belt system supported by a plurality of rollers, which belt system comprises the means for conveying envelopes into a stack of previously fed envelopes. One of the rollers is located adjacent the stack of envelopes, whereby the portion of the conveyor belt system passing over that particular roller is in contact with the stack of envelopes, and specifically in direct contact with the most recent envelope added to the stack. This one roller is rotatably supported on an axially moveable shaft disposed, in one embodiment, at one end of a lever arm, which lever arm is pivotally mounted to the base of the stacking mechanism. The other end of the lever arm, which is beyond the pivotal mounting point, includes means for biasing the lever arm such that the roller on the opposite end of the lever arm is urged toward the stack of envelopes. The belt portion extending around the axially moveable roller is biased to pivot into contact with the stack of articles with a force that counteracts the ever increasing force applied by the stack against the envelope conveying belt system. The force of the stack moves the axially moveable roller, which then acts as a sensing means to detect when the stack force or pressure reaches a predetermined maximum value. When this value is reached, the movement of the roller activates a motor operated drive mechanism which causes a horizontally disposed belt transport system upon which the stack of envelopes is supported to move the stack of envelopes away from, and relieve the pressure upon, the belt system of the envelope conveying means.
Another embodiment includes an envelope conveying system having a roller moveable in a substantially linear direction and a biasing element, such as a spring, operably coupled to the roller support structure for counteracting the force exerted by the stack of articles on the belt system of the envelope conveying means.
Another aspect of the present invention provides a kicker arm assembly which senses the trailing edge of an envelope entering the stacker region adjacent the envelope conveyor belt system, and applies a force to kick the trailing edge of each envelope away from the belt system and onto an auger to provide additional force to move the trailing edge of each document entering the stack out of the path of the leading edge of each subsequently fed envelope.
The method of the present invention for stacking sheet-like articles on edge of the present invention includes: conveying the individual documents into a stack of documents; sensing the force exerted by the stack of documents on a stacker infeed belt regardless of the angular disposition of the last documents added to the stack, and reducing the force exerted by the stack of documents on the stacker belts in response to the sensing of the force by moving the stack of documents in a direction away from the stacker belt system.
BRIEF DESCRIPTIONS OF THE DRAWINGS
FIG. 1 is a top view schematically depicting a stacking apparatus constructed in accordance with the present invention, with the envelope kicker mechanism not shown;
FIG. 2 is a front elevation view of the stacker belts and kicker mechanism forming the document drive of the present invention, with a portion of the stacker belts and rollers cut away to illustrate the kicker mechanism;
FIG. 3 is a top view schematically illustrating the kicker arm assembly of the present invention for kicking the trailing edge of each envelope away from the envelope conveying belt system and onto an auger element; and
FIG. 4 is an additional embodiment of a moveable sensor mechanism constructed in accordance with the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
FIG. 1 generally illustrates the preferred embodiment of the stacking apparatus 10 of the present invention having an introductory conveying path 12 for a document such as an envelope 14, a controllable discharge or document transport magazine 16, a stacking belt assembly 18, and a movable roller sensing mechanism 20. The introductory document conveying path 12 includes a feed belt 22 rotatable about a plurality of rollers 24 which drive belt 22 in the direction shown by arrow A. The path 12 may accept envelopes from a prior envelope feeding stage or other envelope processing stage. The feed belt 22 drives the envelope into contact with the stacking belt assembly 18 by virtue of the spatial proximity of the two belt assemblies. Alternately, feed belts 22 may comprise a pair of vertically separated 0-rings extended over pulleys used in place of rollers 24. The 0-rings are adapted to provide the same function as belts 22, which is to advance an envelope into contact with stacking belt assembly 18, as will be explained.
As seen in FIGS. 1 and 2, the stacker belt assembly 18 comprises a pair of elastic stacker belts 26a and 26b rotatable about axially fixed dual idler rollers 28a and 28b, axially fixed drive rollers 30a and 30b, and axially movable dual rollers 32a and 32b. Moveable roller 32 is rotatably mounted on a shaft 34 which shaft is mounted on a pivotally mounted lever arm 36. Lever arm 36 is rotatably mounted on a shaft 38, which in turn is fixed to a base plate 40 and a top plate 42 (FIG. 2) which form part of the static support assembly for the stacking apparatus 10.
The stacker belts 26a and 26b extend about a triangular course of travel formed by the rollers 28a, 28b, 30a, 30b, 32a and 32b. A drive shaft 44 is connected to a prime mover and to rollers 30a and 30b, and drives the axially fixed drive rollers 30a and 30b in a clockwise direction as viewed in FIG. 1. As will be explained, shaft 34 supporting rollers 32a and 32b is axially biased toward the stack of envelopes 46, and forces a portion 64 of belts 26a and 26b outwardly and into contact with the last stacked envelope 50 of the stack 46.
The movable roller sensing mechanism 20 includes the axially moveable dual rollers 32a and 32b, lever arm 36, and a biasing mechanism generally denoted 52. Lever arm 36 has a first end 54a and a second end 54b. Moveable rollers 32a and 32b are attached to the first end 54a, and are rotatable about shaft 34 and axially pivotal about shaft or post 38, as previously described. The second end 54b of arm 36 engages one end of biasing mechanism 52 via an adjustable screw 56. The distal end of the biasing mechanism 52 is secured to a non-movable post 58. The biasing mechanism 52 extends through the space between dual stacker belts 26a and 26b (FIG. 2). Adjustable screw 56 extends toward the wand 60 of a switch mechanism comprising microswitch 62, whereby the movement of screw 56 actuates the microswitch. As viewed in FIG. 1, biasing mechanism 52 biases lever arm 36 in a counterclockwise direction around shaft 38, forcing rollers 32a and 32b and belt portion 64 outward towards envelope stack 46.
Stop member 66 provides a limit to the counterclockwise rotation of the lever arm 36 and moveable rollers 32a and 32b about shaft 38. The biasing mechanism 52 serves to urge the lever arm 36 away from the switch mechanism 62. Switch mechanism 62 is electrically coupled to a motor 69 or other prime mover that controls the movement of magazine conveyor belts 68a and 68b.
Discharge magazine 16 includes conveyor belts 68a and 68b, an adjustable compression plate 70 slidable along guide rod 72, and a document stop element 74. Each conveyor belt 68a, 68b, extends around a pair of pulleys (not shown). One of the pulleys associated with each belt 68a, 68b is driven by a suitable motor 69, which motor 69 is operatively connected to and actuated by switch 62. The conveyor belts 68a and 68b transport the envelopes in stack 46 in a direction shown by arrow 76, and are activated by the motor when the adjustable screw 56 contacts the switch mechanism 62. The stack of envelopes 46 is vertically disposed on top of and supported by belts 68a and 68b.
After the last to be stacked envelope 50, as will be explained, reaches discharge magazine 16 and the leading edge of envelope 50 abuts stop element 74, portion 64 of stacker belt 26 holds envelope 50 at an angle relative to the longitudinal direction of magazine 16. In addition, portion 78 of belt 26 extends away from discharge magazine 16 on the upstream side of rollers 32a and 32b relative to belt portion 64. As a result, a variable entrance angle 80 is formed between envelope 50 and belt portion 78. This is the entrance angle thru which envelopes 14 are transported to stack 46.
The present invention also includes a kicker arm assembly 82 (FIGS. 2, 3) for kicking the trailing edge of each envelope 14 away from belt portion 78 and onto auger 84. Auger 84 (FIGS. 1, 3) comprises a helix 85 rising slightly above the upper surface of base plate 40 which engages the bottom edge of each envelope 14 as the envelope is kicked away from belt portion 78 by kicker arm assembly 82. The auger 84 moves the trailing edge of each envelope 14 through entrance angle 80, thereby creating a space for the advancement of the next envelope into the stack 46 without causing interference with the trailing edge of the preceding envelope.
Kicker arm assembly includes a vertically disposed mounting bracket 86 fixed to base plate 40, as best seen in FIG. 2. A mounting plate 88 is fixed to and extends from the top of bracket 86, and an aperture 90 extends through an outer portion of mounting plate 88. Shaft 92 is rotatably mounted through aperture 90, and extends downward through an aperture in base plate 40. The lower end of shaft 92 is attached to the operating shaft 94 of a rotary operating solenoid 96. Shaft 94 is adapted to be rotated through a limited circular angle when solenoid 96 is actuated.
A pair of extendable arms 98a, 98b are fixed to shaft 92, and a pair of kicker arms 100a, 100b are attached to extendable arms 98a, 98b respectively. Kicker arm 100a is vertically located on shaft 92 such that when shaft 92 is rotated by solenoid 96 in the counterclockwise direction 16 as viewed in FIG. 3, kicker arm 100a extends between belts 26a and 26b. In similar fashion, kicker arm 100b is vertically located on shaft 92 such that when shaft 92 is rotated counterclockwise (FIG. 3) by solenoid 96, kicker arm 100b extends in the space between belt 26b and the upper surface of base plate 40. When solenoid 96 is actuated, shaft 92 rotates in a clockwise direction (FIG. 3), moving kicker arms 100a and 100b to the retracted position seen in FIG. 3. When solenoid 96 is de-activated, a spring mechanism (not shown) biases the outer ends of kicker arms 100a and 100b to extend outward beyond the vertical plane of belt portions 78 to engage the trailing edge of a moving envelope 14 as the envelope is driven towards the stack 46, thereby driving the trailing edge of the envelope through angle 80 and onto auger 84 and helix 85. The helix drives the trailing edge of the envelope in a direction away from belt portion 78, providing space for the transport of the next envelope into the stack without jamming.
A photocell sensor element 102 (FIG. 3) is mounted on base plate 40 adjacent the path traveled by each envelope 14 and just ahead of mounting bracket 86. Sensor element 102 is electrically connected through line 103 to solenoid 96. As each envelope 14 advances, sensor 102 detects the leading edge of the envelope, and sends a signal through line 103 to actuate the solenoid, rotating shaft 92 clockwise (FIG. 3), thus retracting kicker arms 100a, 100b out of the path of the advancing envelope. As the envelope 14 moves forward, sensor 102 eventually detects the trailing edge of the envelope, and sends another signal through line 103 which de-actuates solenoid 96, whereby the spring mechanism rotates shaft 92 counterclockwise, extending kicker arms 100a, 100b outward beyond the vertical plane of belts 26a, 26b. As stated previously, kicker arms 100a, 100b force the trailing edge of the envelope 14 outward and onto auger 84. The vertical location of kicker arms 100a, 100b is preferably fixed such that the arms will contact regular sized envelopes as well as flat or larger sized envelopes.
In the operation of the embodiment disclosed in FIGS. 1 and 2, an envelope 14 is conveyed by the stacking belt assembly 18 along linear introductory path 12 until the leading edge of the envelope 14 contacts the most recently stacked envelope 50 after passing through the acute entrance angle 80. As the stacker belts 26a and 26b move, the leading edge of each envelope 14 is bent around bend point 104 and interposed between the most recently stacked envelope 50 and portion 64 of stacker belts 26a and 26b. The trailing edge of the envelope is displaced through the entrance angle 80 with the aid of auger 84 so that the trailing edge "fishtails" through the entrance angle. The bottom margin of the trailing edge of the envelope 14 is engaged to ride in the helical threads 85 of the rotating auger element 84 to propel the trailing edge of each envelope 14 into the stack and away from stacking belt assembly 18 to provide space for subsequently fed envelopes.
The present invention includes a unique sensing mechanism that provides a broad plane of contact with the last stacked envelope and also varies the stacker belt tension about the rollers 28a and 28b, 30a and 30b, and 32a and 32b. The moveable roller sensing mechanism 20 forms part of the stacking belt assembly 18. As more envelopes are sequentially stacked in the discharge magazine 16, a normal compressive force or pressure is developed in the stack 46 in opposition to the bias element 52 exerts on the moveable rollers 32a and 32b. This normal force causes the lever arm 36 to rotate in a clockwise direction, thereby slightly decreasing the entrance angle 80 and reducing the tension on the stacker belts 26a and 26b. When the force applied by the stack 46 to the movable rollers 32a and 32b exceeds the force applied to the moveable rollers by the biasing mechanism 52, the adjustable screw 56 engages microswitch 62 and activates the motor driving magazine conveyor belts 68a and 68b.
The conveyor belts 68a and 68b then convey the envelopes away from the stacker belts 26a and 26b in the direction of arrow 76, thereby relieving the pressure force previously exerted on the movable rollers 32a and 32b and allowing the lever arm 36 to rotate in the counterclockwise direction under the bias of mechanism 52. This causes the adjustable screw 56 to disengage from switch mechanism 62 which de-activates the motor connected to magazine conveyor belts 68a and 68b. The envelopes in the front part of stack 46 fan out as pressure is relieved, allowing additional envelopes to be sequentially fed into the stack without interference from the trailing edge of previously stacked envelopes.
Undesirable variations in pressure sensing by the movable roller sensing mechanism 20 due to slack in the stacker belts 26a and 26b is further reduced by the direction of movement of the stacker belts 26a and 26b. The drive roller 30 rotates clockwise as viewed in FIG. 1, and pulls the stacker belts 26 tightly over movable rollers 32a and 32b while "pushing" the stacker belts 26a and 26b toward idler rollers 28a and 28b. Therefore, any slack in the stacker belts 26a and 26b is developed in the top run of the triangular path between drive rollers 30a and 30b and idler rollers 28a and 28b. Belts 26a and 26b remain taught as they travel from idler rollers 28a and 28b to axially moveable rollers 32a and 32b, and from moveable idler rollers 32a and 32b to drive rollers 30a and 30b. This taughtness of belts 26a and 26b adjacent rollers 32a and 32b enhances the accuracy of roller sensing mechanism 20.
As illustrated in FIG. 2, the lever arm 36 is vertically situated adjacent the gap between stacker belts 26a and 26b. Shaft 38 and non-moveable stop member or post 66 are fixedly secured to base plate 40 via attachment bolts 110, 112.
The plane of contact between the movable roller sensing mechanism 20 and envelopes 14 comprises the broad surfaces of the dual stacker belts 26a and 26b, rather than a separate rod or arm type sensing lever with a small plane of contact, as found in the prior art. The stacker belts 26a and 26b of the present invention are used both to transport envelopes directly into the stack 46 and also to form a broad pressure sensing surface which senses stack pressure accurately regardless of the tilt of the forward envelopes.
Kicker arm assembly 82 cooperates with the stacking belt assembly 18 and the roller sensing mechanism 20 to move the trailing edge of each envelope away from the path of subsequently fed envelopes as each prior envelope reaches the stack 46. As described previously, kicker arm assembly operates to kick the trailing edge of each envelope as it reaches the stack in a direction toward the stack and onto auger 84, and out of the primary path of envelope travel, as defined by introductory conveying path 12 and belt portion 78 of stacking belt assembly 18. The trailing edge of each envelope is therefore removed from possible interference with the leading edge of an incoming envelope. As the number of unimpeded envelopes entering the stack increases, the normal force applied by the stack of envelopes against the roller sensing mechanism 20 increases to the point where the compressed stack of envelopes presents another impediment to rapid introduction of envelopes into the stack. As explained, when the normal force reaches a predetermined limit, the magazine conveyor belts 68a and 68b are driven to relieve the stack pressure adjacent the stacking belt assembly 18.
As appreciated by those having ordinary skill in the art, a single belt 26 configuration may also be suitable, provided the width of the belt 26 that forms the contact surface is proportionally wide enough to contract a substantial portion of each envelope.
FIG. 4 illustrates an alternative embodiment of the roller sensing mechanism of the present invention, comprising a substantially linearly moving sensor element. A spring loaded sensing roller 20' replaces the roller sensing mechanism 20 shown in FIGS. 1, 2 and 3. As illustrated in FIG. 4, linear displacement occurs in the horizontal direction, as indicated by arrow 120, as opposed to the rotational displacement of the moveable sensing mechanism 20 of FIG. 1. A hollow cylindrical member 122 is fixedly mounted to a vertically extending sleeve 124 through which rotatable shaft 34 extends. Moveable roller 32 is rotatably mounted on shaft 34. The cylindrical member 122 houses biasing element 126, which is substantially restricted to linear movement by guide plates 128 and 130. A lever 132 is attached to an end of sleeve 124, and is adapted to contact and move wand 134 of microswitch 136.
The operation of the alternate embodiment of FIG. 4 is similar to the operation of the embodiment of FIG. 1. As stack pressure increases, moveable roller 32' moves horizontally in the direction of the application of stack pressure, driving shaft 34', sleeve 124, hollow cylindrical member 122 and lever 132 in the same direction. When the stack pressure has reached a predetermined maximum limit, lever 132 comes into contact with wand 134, activating microswitch 136 and moving magazine conveyor belts 68a and 68b in a direction away from stacking belt assembly 18. Although a spring is shown as a representation of biasing element 126, other suitable biasing elements can be substituted therefor.
While the invention has been particularly shown and described with reference to the preferred embodiments thereof, it will be understood by those having ordinary skill in the art that numerous variations in form and detail may be made without departing from the spirit and scope of the invention, as set forth in the following claims. | An apparatus and method for stacking a plurality of flat articles on edge, comprising a discharge magazine for sequentially receiving and stacking the flat articles in a stack, the discharge magazine including moveable discharge support belts adapted to support the stack of articles on edge and a moveable compression plate to maintain the articles on edge. A drive element is provided for controllably moving the discharge support belts. A stacker section adjacent the discharge magazine transports articles sequentially into the stack, the stacker section comprising stacker belts extending around a plurality of rollers.
The last of the articles in the stack abuts against the stacker belts adjacent one of the rollers to apply a compressive force developed by the stack of flat articles and the compression plate to the one roller. The one roller is movably mounted to the apparatus for movement responsive to increases and decreases in the compressive force. An actuator element is operatively connected to and responsive to movement of the one roller and connected to the drive element for activating the drive element and the discharge support belts to transport the stack of flat articles away from the stacker section when the compressive force reaches a predetermined maximum value. | 1 |
The invention described herein was made in the course of work under a grant from the United States Department of Health, Education and Welfare.
This is a division, of application Ser. No. 901,358, filed May 1, 1978, now U.S. Pat. No. 4,191,755.
BACKGROUND OF THE INVENTION
The invention relates to antitumor compounds which are anthracyclines, and in particular, to a new class of daunomycin derivatives and the aglycones thereof. The invention also relates to the use of these new compounds in treating mammalian tumors. Also within the scope of the invention are certain novel intermediates used in the preparation of the compounds of the invention.
SUMMARY OF THE INVENTION
The invention provides, in one aspect thereof, a new class of daunomycin derivatives of the formula I: ##STR2## wherein R 1 is a lower alkyl having from 1 to 4 carbon atoms and R is hydrogen or a tirfluoroacetyl group.
These compounds are prepared from the respective aglycones of the formula II (which are derivatives of daunomycinone) by condensation with an N,O protected daunosamine derivative. The aglycones of the formula II: ##STR3## wherein R 1 is as defined above, are another aspect of the present invention.
The aglycones of the formula Ii are in turn prepared according to the following reaction sequence starting from intermediate V. The preparation of intermediate V from daunomycinone is described in co-pending application Ser. No. 901,359, filed May 1, 1978 and now Pat. No. 4,191,756, i.e., the U.S. counterpart of British application No. 18777/77. ##STR4## wherein R 1 is as defined above and R 2 is as defined hereinafter.
We have now surprisingly found that, under carefully controlled conditions, compound V can react in a highly regiospecific manner with a halide of the general formula R 1 -Y, where R 1 is as defined above and Y is Cl, Br or I, to afford the monoether-derivative VI. Such selectivity was completely unexpected, since a much higher reactivity of the C-11-OH with respect to the C-4-OH is unpredictable a priori. The reaction is carried out in a solvent such as dichloromethane, chloroform, and the like in the presence of one equivalent of a base such as silver oxide and the like and a slight excess of the halide. Compound VI, on treatment with a dilute alkaline hydroxide or with an activated basic resin such as AG1--X2 and the like, gives rise to the bis-phenolic derivative VII, wherein R 2 is hydrogen when the reaction is carried out in an aqueous medium and preferably, is an alkyl group, when an alcohol, such as methanol, is used as the solvent. In the latter case, compound VII is hydrolyzed by mild exposure to aqueous trifluoroacetic acid to yield the new aglycones II together with small amounts of the 7-epimers thereof, which, in turn, can be transformed into aglycone Ii, having the 7-α-OH, following the equilibration procedure described in J. Am. Chem. Soc. 98, 1967 (1976). The biologically active glycosides of formula I are prepared by condensing an aglycone of the formula II (according to the procedure for the synthesis of glycoside linkages described in Belgian Pat. No. 842,930, owned by the unrecorded assignee hereof with a protected 1-halo-sugar in a suitable organic solvent such as dichloromethane or chloroform, in the presence of a soluble silver salt as a catalyst. In the present case, the aglycone II is condensed with 1-chloro-N,O-bis-trifluoroacetyldaunosamine, to form the N,O protected glycoside VIII: ##STR5## which, on treatment with methanol and a catalytic amount of triethylamine, is converted into the N-trifluoroacetyl protected glycoside which can be successively hydrolyzed, by mild exposure to a dilute alkaline base, to form the free glycosidic base which is finally isolated as the hydrochloride. The new compounds of the formula I, display antimitotic activity and are useful therapeutic agents for the treatment of certain mammalian tumors.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The following examples are given to illustrate the invention without, however, being a limitation thereof.
EXAMPLE 1
4-Demethoxy-4-hydroxy-11-deoxy-11-methoxy-O 6 ,O 7 -bis-ethoxy-carbonyldaunomycinone
5 Grams of 4-demethoxy-4-hydroxy-O 6 ,O 7 -bis-ethoxy-carbonyldaunomycinone were dissolved in 100 ml. of dichloromethane and treated with 1.5 ml. of methyl iodide and 1.5 g. of silver oxide. After refluxing for 2 hours, the reaction mixture was filtered and evaporated to a residue. The residue was chromatographed (silica gel; dichloromethane) to afford pure 4-demethoxy-4-hydroxy-11 -deoxy-11-methoxy-O 6 ,O 7 -bis-ethoxycarbonyldaunomycinone.
PMR (CDCl 3 ): 1.33 and 1.46δ(two t, CH 3 -C(H 2 )), 2.36δ(s, CH 3 CO), 3.83δ(s, CH 3 O), 4.23 and 4.36δ(two q, CH 2 -C(H 3 )), 6.13δ(broad s, C-7-H), 7.0-7.8δ(m, 3 aromatic protons), 12. 2δ(s, phenolic hydroxyl).
IR (KBr): 1765, 1740, 1715, 1675, 1635, 1580 cm -1 .
Example 2
4-Demethoxy-4-hydroxy-7,11-bis-deoxy-7,11-bis-methoxydaunomycinone
A solution of 1.5 g of 4-demethoxy-4-hydroxy-11-deoxy-11-methoxy-O 6 ,O 7 -bis-ethoxycarbonyldaunomycinone in a 1:1 mixture of dichloromethane-methanol was treated with an excess of AG1-X2 resin which had been previously activated with aqueous sodium hydroxide and washed with methanol. The reaction mixture was stirred until the starting material had completely disappeared, and then was filtered and evaporated to a residue which was chromatographed (silica gel; chloroform:acetone 95:5, v/v) to give 4-demethoxy-4-hydroxy-7,11-bis-deoxy-7,11-bis-methoxydaunomycinone.
PMR (CDCl 3 ): 2.40δ(s, CH 3 CO), 3.56 and 3.80δ(two s, two CH 3 O), 4.85δ(broad s, C-7-H), 6.9-8.3δ(m, 3 aromatic protons), 11.7 and 12.9δ(two s, phenolic hydroxyls).
IR (KBr): 1716, 1670, 1622, 1598 and 1585 cm -1 .
EXAMPLE 3
4-Demethoxy-4-hydroxy-11-deoxy-11-methoxydaunomycinone and its 7-epimer
1.2 Grams of 4-demethoxy-4hydroxy-7,11-bis-deoxy-7,11-dimethoxydaunomycinone were dissolved in 40 ml. of trifluoroacetic acid containing 2% of water, and the resulting solution was left to stand overnight at room temperature. After removal of the solvet in vacuo, the residue was dissolved in acetone and hydrolyzed with concentrated aqueous ammonia. The reaction mixture was diluted with chloroform, washed with water and evaporated to a residue which was chromatographed to afford two products: 4-demethoxy-4-hydroxy-11-deoxy-11-methoxydaunomycinone (Rf=0.54 on silica gel plate; chloroform:acetone 4:1, v/v) and its 7-epimer (Rf=0.3). If desired, the 7-empimer can be converted to the natural configuration by treatment with dilute trifluoroacetic acid. PMR and IR of 4-demethoxy-4-hydroxy-11-deoxy-11methoxydaunomycinone:
PMR (CDCl 3 ): 2.45δ(s, CH 3 CO), 3.96δ(s, CH 3 O), 5.27δ(broad s, c-7-H), 7.0-7.9δ(m, 3 aromatic protons), 11.7 and 13.0δ(two s, phenolic hydroxyls).
IR (KBr): 1715, 1670, 1625, 1600 and 1580 cm -1 .
EXAMPLE 4
4-Demethoxy-4-hydroxy-11-methoxydaunomycinone and its 7-epimer
The two compounds named above were obtained directly by treatment of 4-demethoxy-4-hydroxy-11-deoxy-11-methoxy-O 6 , O 7 -bis -ethoxycarbonyldaunomycinone with AG1-X2 resin as described in Example 3, but carrying out the reaction in aqueous dichloromethane instead of methanolic dichloromethane and using wet resin.
EXAMPLE 5
4-Demethoxy-4-hydroxy-11-deoxy-11-methoxy-N-trifluoroacetyldaunomycin
To a solution of 1.5 g. of 4-demethoxy-4-hydroxy-11-deoxy-11-methoxydaunomycinone and 1.25 g. of 2,3,6-trideoxy-3-trifluoroacetamido-4-O-trifluoraecetyl-α-L-lyxopyranosyl chloride (1-chloro-N,O-bis-trifluoroacetyldaunosamine) in 100 ml. of anhydrous dichloromethane, a solution of 0.95 g. of silver trifluoromethanesulphonate in anhydrous diethyl ether was added dropwise at room temperature under stirring. After 1 hour the reaction mixture was washed with aqueous NaHCO 3 and evaporated to a residue which was dissolved in methanol containing a catalytic amount of triethylamine and left to stand at room temperature for two hours. The solvent was removed in vacauo and the residue chromatographed (silica gel chloroform-acetone 95:5, v/v) to give 4-demethoxy-4-hydroxy-11-deoxy-11-methoxy-N-trifluoroacetyldaunomycin.
PMR (CDCl 3 ): 1.29δ(d, CH 3 -C(H), 2.40δ(1, CH 3 CO), 3.83δ(s, CH 3 O), 5.15δ(s, C-7-H), 5.39δ(s,C-1'-H), 7.0-8.0δ(m, NH and aromatic H), 11.76 e 13.04δ(2s, phenolic H).
EXAMPLE 6
4-Demethoxy-4-hydroxy-11-deoxy-11-methoxydaunomycin hydrochloride
0.9 Gram of 4-demethoxy-4hydroxy-11-deoxy-11-methoxy-N-trifluoroacetyldaunomycin was dissolved in 40 ml. of aqueous 0.15 N NaOH and left to stand 1 hour at room temperature. After acidification with oxalic acid and rapid neutralization with aqueous NaHCO 3 , the product was extracted with chloroform and the organic solution was evaporated to a residue which was dissolved in dichlororomethane and treated with 1 equivalent of HCl in methanol. By addition of diethyl ether, 4-demethoxy-4-hydroxy-11-deoxy-11-methoxydaunomycin hydrochloride was precipitated and collected by filtration.
Rf=0.38 (CHCl 3 -CH 3 OH-H 2 O=13:6:1 v/v)
M.P.: 174°-176° C. dec.;λmax=446 nm.
BIOLOGICAL ACTIVITY
The compound: 4-demethoxy-4hydroxy-11-deoxy-11-methoxy-daunomycin was tested under the auspices of N.C.I., National Institute of Health, Bethesda, Maryland, U.S.A., against Lymphocitic Leukemia P 388 according to the procedure described in Cancer Chemotherapy Reports, Part 3, Vol. 3, page 9 (1972). The following table illustrates the antitumor activity thereof.
The above compound was compared to daunomycin in a test consisting of mice infected with tumor cells: the injections were made on days 5, 9 and 13 with a 4 day interval between each single injection starting from the fifth day from the tumor transplantation in mice.
TABLE______________________________________ Schedule of Treatment in DoseCompound days (i.p.) mg./kg. T/C %______________________________________Daunomycin . HCl 5,9,13 32.00 16.00 86 8.00 108 4.00 134 2.00 1314-Demethoxy-4-hydroxy- 5,9,13 50.00 12511-deoxy-11-methoxy- 25.00 122daunomycin . HCl 12.50 119 6.25 119 3.13 118______________________________________
Variations and modifications can, of course, be made without departing from the spirit and scope of the invention. | Daunomycin derivatives of the formula: ##STR1## wherein R 1 is a lower alkyl having from 1 to 4 carbon atoms and R is hydrogen or a trifluoroacetyl group are useful in treating certain mammalian tumors. | 2 |
FIELD OF THE INVENTION
The present invention involves the industrial production of a series of aluminum profiles for the construction of curtain walls with suspended glassed panels.
BACKGROUND OF THE INVENTION
The structure and shape of the frame of the curtain walls manufactured today in Greece and internationally are based on the traditional structure of the frame with a grid of vertical beams. The vertical beams extend across all the height of the curtain wall as continuous beams. Small horizontal beams transverse and are positioned between the vertical ones. The glassed panels are placed onto this grid in contact both with the vertical and the horizontal elements, and are supported by it.
This structure of the frame has several problems and weaknesses, mainly concerning thermal expansion, antiseismic properties, tightness, safety and operation of the windows, strength and durability of the sealing materials, the general construction cost, etc.
SUMMARY OF THE INVENTION
The above problems and weaknesses are addressed efficiently with the construction of curtain walls with suspended glassed panels, to which the present invention relates.
The objects of the present invention are basically obtained by a curtain wall of a predetermined height, comprising prefabricated glassed panels, and a frame having only horizontal beams into which the glassed panels are placed for supporting the glassed panels, without continuous vertical beams existing along the height of the curtain wall on a building with multiple floors.
With this invention, the elements of the glasses—glassed panels, prefabricated at the plant, are placed onto the frame of the curtain wall, and are suspended only from the horizontal beams of the frame along their whole length. The glassed panels do not touch the vertical beams. The vertical beams only support the horizontal beams onto the slabs of the floors of the building.
Other objects, advantages and salient features of the present invention will become apparent from the following detailed description, which, taken in conjunction with the annexed drawings, discloses preferred embodiments of the present invention.
BRIEF DESCRIPTION OF THE DRAWINGS
Referring to the drawings which form a part of this disclosure:
FIG.1 is a partial, perspective view of a frame for a curtain wall attached to floor slabs of a building;
FIG. 2 is an enlarged, partial, perspective view of the frame of FIG. 1;
FIG. 3 is a partial perspective view of a building structure with glassed panels and the frame of FIG. 1;
FIGS. 4 A-C are end elevational views of alternative profiles for the cantilevers for the frame of FIG. 1;
FIG. 5 is a partial, enlarged, side elevational view in section of the frame of FIG. 1 with glassed panels, at the upper horizontal beam;
FIG. 6 is a partial, enlarged, side elevational view in section of the frame of FIG. 1 with glassed panels at the lower horizontal beam;
FIG. 7 is a partial, enlarged, side elevational view in section of a vertical beam and glassed panels according to the present invention; and
FIG. 8 is a partial, enlarged, top plan view in section at a corner of the curtain wall according to the present invention.
DETAILED DESCRIPTION OF THE INVENTION
Each floor of the curtain wall has two horizontal beams parallel to each other and continuous, along the length of the structural facade of the floor. One horizontal beam 1 . 1 , 2 . 1 is at the height of the base of the windows, the lower horizontal beam of the floor (FIGS. 1 and 2 ). The other horizontal beam 1 . 2 , 2 . 2 is at the same height as the top of the windows, the upper horizontal beam of the floor (FIGS. 1 and 2 ).
These horizontal beams are supported on the ends of small cantilevers 1 . 3 , 2 . 3 anchored on the slabs of the floors of the building. The cantilevers are fastened on the floor slab of the floor and have upwardly directed supports at their ends for the horizontal beam at the same height as the base of the windows, the lower horizontal beam of the floor. The cantilevers fastened to the roof slab of the floor also have downwardly directed supports at their ends for the horizontal beam at the same height as the top of the windows, the upper horizontal beam of the floor which constitutes the beam for the suspension and opening of the windows. The upper horizontal beam has special hooks along its whole length. The hooks correspond to the respective hooks of the upper side of the frames of the windows.
In case of continuity of the curtain wall to a lower or upper floor, the two cantilevers 1 . 3 , 2 . 3 are unified as beams bilaterally protruding towards the continuous floors (FIGS. 1 and 2 ). However, in the case of unified glassed panel along the height of each floor, the support of the horizontal beams is directly fastened at the roof and floor slabs of the floor.
With the above support of the horizontal beams and the means of suspension and opening of the windows, continuity of vertical beams between the two horizontal beams of each floor does not exist. Hence, the construction of continuous windows along the length of the floor is easy and has a limited cost (FIG. 3 ).
The shape and the dimensions of the horizontal beams and cantilevers, the method of their connection and the fastening method depend on the materials of construction of the building and the dimensions of the slabs of the building.
Application of the present invention can constitute a series of aluminum profiles illustrated in FIGS. 4-7. FIGS. 4A-C illustrate profile forms of cantilevers, as in the embodiments of FIGS. 1 and 2. FIG. 5 illustrates the functional composition of the upper horizontal beam for the suspension of the windows in which cantilever 5 . 1 and upper horizontal beam 5 . 2 suspend the windows with hook 5 . 3 . The upper horizontal side of the window frame has the mutual hook 5 . 4 for the suspension of the windows. The lower horizontal side 5 . 5 of the frame supports fixed glass panels.
FIG. 6 illustrates the functional composition of the lower horizontal beam for the suspension of the fixed glass panels, and includes a cantilever 6 . 1 , a lower horizontal beam 6 . 2 for the suspension of fixed glass panels, an upper horizontal side 6 . 3 of the frame of fixed glassed panels and a lower horizontal side 6 . 4 of the window frame.
FIG. 7 illustrates the functional composition of the vertical beam, with vertical sides of the frames for the windows and fixed glass panels.
FIG. 8 illustrates the functional composition of a corner beam.
All the profiles, which constitute the panel of the glassed panels, bear special incisions for the attachment and support on them of aluminum blades made of special alloy compatible with the adherence requirements of the sealing materials. In this manner, a better quality and long lasting retention of the glasses onto the aluminum frames of the glassed panels, as illustrated in FIGS. 5-8, are provided.
While various embodiments have been chosen to illustrate the invention, it will be understood by those skilled in the art that various changes and modifications can be made therein without departing from the scope of the invention as defined in the amended claims. | A curtain wall of a predetermined height includes prefabricated glassed panels, and a frame. The frame has only horizontal beams into which the glassed panels are placed for supporting the glassed panels without continuous vertical beams existing along the height of the curtain wall on a building with multiple floors. | 4 |
CLAIM OF PRIORITY
This application claims priority from and is a continuation of U.S. patent application Ser. No. 11/395,223 filed Apr. 3, 2006, entitled “METHOD FOR IMPLEMENTING ERROR-CORRECTION CODES IN FLASH MEMORY” which claims the benefit of Provisional Patent Application No. 60/759,397 filed Jan. 18, 2006, the content of each of which is incorporated herein by reference in its entirety.
FIELD OF THE DISCLOSURE
The present disclosure relates to a method and device for implementing error-correction code (ECC) in flash memory.
BACKGROUND
Flash memory devices have been known for many years. Within all flash memory devices, NAND-type memories differ from other types (e.g. NOR-type), among other characteristics, by the fact that a certain amount of information bits, written to the memory, may be read from the memory in a “flipped” state (i.e. different from the state that the original bits were written to the memory).
In order to overcome this phenomenon and to make NAND-type memories usable by real applications, it is a common technique to use ECC in conjunction with these memories. A general overview of using ECC in flash memories is described below which includes the following steps:
(1) Before writing data to the memory, an ECC algorithm is applied to the data in order to compute additional (i.e. redundant) bits, which are later used for error detection and correction. These redundant bits are often called parity bits or parity. A combination of the data input into an ECC module and the parity output by that module is called a codeword. Each different value of input data to an ECC module results in a different codeword.
(2) The entire codeword (i.e. the original data and the parity) is recorded to the flash memory. It should be noted, that the actual size of NAND-type flash memory is larger than the size of the original data, and the memory is designed to accommodate parity as well.
(3) When the data is being retrieved from the memory, the entire codeword is read again, and an ECC algorithm is applied to the data and the parity in order to detect and correct possible “bit flips” (i.e. errors).
It should be noted that the implementation of ECC may similarly be done by hardware, software, or a combination of both of them. Furthermore, ECC may be implemented within a memory device, a memory device controller, a host computer, or may be “distributed” among these components of a system.
Another well-known feature of flash memories is that data may only be programmed to the memory after the memory has been erased (i.e. data in the memory may not be overwritten, but rather erased and written again). The erase operation is performed on relatively large amounts of memory blocks (called erase blocks), and results in setting all the bits of the portion of erased memory to a logic value of one. This means that following an erase operation of a block of a NAND-type memory device, all the pages of that block will contain 0xFF (i.e. hexadecimal FF) data in all their bytes.
If further data is to be programmed to the erased page, the bits which have “zero-logic” (i.e. logic values of zero) will be programmed, while the bits which have “one-logic” (i.e. logic values of one) will remain in an “erased” state.
A vast majority of ECC schemes used with NAND-type flash memory devices have “linear” behavior, which means that for a data word consisting of “all-zero” data bits, all the parity bits have zero-logic as well (i.e. a codeword of all-zero logic, where all the bits have zero-logic, is a legal codeword). However, many of these codes are not “symmetrical” (i.e. the “0xFF” codeword, which is a codeword with both “all-one” data bits and “all-one” parity bits, is not a legal codeword).
As a simple example of the situation mentioned above, one may consider a simple even parity added to a byte of data. While an all-zero codeword (i.e. 0x00 plus zero-parity) is legal, an all-one codeword (i.e. 0xFF plus one-parity) is illegal. This situation may create a logic problem for system implementation as follows. If the system attempts to read a page which happens to be erased, and to apply ECC to the page, the ECC will “detect” that the codeword is wrong and will try to correct the codeword. If the ECC succeeds in correcting the all-one data, incorrect information would be presented to the application.
One may wonder why the system would read erased pages. The reason for this situation arising is that when the system “wakes-up” from power interruption, the system has no a priori knowledge of the location of the data in the flash memory. Therefore, the system has to perform a search of the flash memory medium in order to locate the written data and to reconstruct its RAM-resident databases, which will then allow the system to access data on the flash memory in a quick and efficient way.
During such a search as mentioned above, erased pages may be read in the process. When these pages are read, they should be identified as having been erased in order to enable correct construction of the RAM tables.
It is clear from the above discussion that it would be beneficial to system performance if erased pages could be handled correctly by ECC. By “handled correctly”, it is meant that the ECC will not consider an erased page to have errors. Moreover, it would be beneficial that even in the event that some erased bits of the erased page are accidentally flipped to a “programmed” state, which may occur in practical flash memory devices due to various “parasitic” phenomena, the ECC should correct the affected bits and provide the system with “erased” (i.e. all 0xFF) data.
In some flash memory devices, the erasure procedure actually consists of two stages: (1) all the cells in a block are programmed to the high voltage-level (i.e. zero state), and (2) only after this step has occurred, an erase voltage is applied to the block. This procedure removes the charge from the cells, and converts the cells to the erased state.
The reason for such a two-stage process is to attempt to make all the cells in a block go through the same history of programming and erasing, which ensures that all cells in a block have relatively the same wear effects. In addition, this two-stage erasure procedure helps to make the voltage distributions of the cells narrower, which results in more reliable programming.
If the device power is interrupted following the first stage of such an erasure operation (i.e. following programming all the cells to a zero state), the pages of the block will remain programmed, and will be read upon power restoration as all-zero states. In this case, the ECC will report the correct data of 0x00 for the entire page. This may result in the flash-memory management algorithm, which attempts to reconstruct the flash memory database, being mislead.
Although the probability of the occurrence of such an event is not high (because power interruption would have to occur immediately following completion of the first stage of the erasure operation, but prior to initiation of the second stage), it would be beneficial for the system to have an “operation error” indication for this scenario.
SUMMARY
For the purpose of clarity, the term “complement” is specifically defined for use within the context of this application. The term “complement” is used to describe the inversion of every bit of data in a codeword (e.g. zero-logic is the complement of one-logic, and one-logic is the complement of zero-logic).
It is the purpose of the present disclosure to provide methods and means for implementing ECC in flash memory.
A method for storing a plurality of data bits into a non-volatile memory device includes performing, in a data storage device, transforming a plurality of data bits to be stored in a non-volatile memory device to generate a plurality of transformed data bits, and generating a parity bit corresponding to the plurality of transformed data bits. The method further includes transforming the parity bit and storing the plurality of data bits and the transformed parity bit in the non-volatile memory device. Each of the plurality of data bits and the parity bit form an all-one codeword.
In addition, a data storage device is disclosed and comprises a non-volatile memory and a memory controller. The memory controller is configured to transform a plurality of data bits to generate a plurality of transformed data bits, to generate a parity bit corresponding to the plurality of transformed data bits, to transform the parity bit, and to store the plurality of data bits and the parity bit in the non-volatile memory. Each of the plurality of data bits and the transformed parity bit form an all-one codeword.
These and further embodiments will be apparent from the detailed description and examples that follow.
BRIEF DESCRIPTION OF THE DRAWINGS
The present disclosure is herein described, by way of example only, with reference to the accompanying drawing, wherein:
FIG. 1 shows a simplified schematic diagram of a flash memory device with implemented ECC according to embodiments of the present disclosure.
DETAILED DESCRIPTION
The present disclosure is of a method and device for implementing ECC in flash memory. The principles and operation for implementing ECC in flash memory, according to the present disclosure, may be better understood with reference to the accompanying description and the drawing.
Embodiments of the present disclosure rely on the main step of switching between all-zero codewords and all-one codewords, making all-one codewords legal and all-zero codewords illegal from the perspective of the ECC.
This may be accomplished by inverting the data and the parity in the course of the ECC computations as follows: (1) for computing the parity, use the complement of the data (but store the original data in the flash memory); (2) store in the flash memory a complement of the parity which was computed in step (1); and (3) while reading the data, use the complement of the data and the complement of the stored parity for error detection and correction functions.
Let us consider the example, from the background section of this application, in which the ECC computations are modified in accordance with the above. In that example the codewords have eight data bits plus one parity bit, where all legal codewords have an even number of one-logic data bits. As is known in the art, a simple code scheme such as this can detect the existence of one error in a codeword, but has no error-correction capability. Embodiments of the present disclosure are described with reference to this type of simple code scheme in order to make it easy to understand them. However, as can be recognized, the present disclosure is similarly applicable to various code schemes of differing complexity, as long as the code scheme includes the criterion of the all-zero codeword being a legal codeword.
Applying the above-mentioned method to the example provides:
(1) The data byte of 0x00 will be converted to 0xFF for the sake of parity computation, and will have zero-parity. Therefore, this data will be recorded into the flash memory as a codeword of 0b000000001.
(2) The data byte of 0xFF will be converted to 0x00 for the computation of parity, and will have zero-parity. Therefore, this data will be recorded into the flash memory as a codeword of 0b11111111. [0045] (3) Reading the codeword of 0x000000001 will result in data 0x00, and will have zero-parity, which is a legal codeword. [0046] (4) Reading the codeword of 0x1111111111 will result in data 0xFF, and will have zero-parity, which is a legal codeword as well. [0047] (5) Reading the codeword of 0x000000000 will result in data 0x00, and will have one-parity, which indicates an operation error.
One may see, that case (4) above exactly represents the case of an erased page (which has both all-one data and all-one parity), and as was our goal, results in the ECC considering it a legal codeword. Case (5) represents the situation in which the power to the flash memory has been interrupted immediately following the first stage of the erase process (i.e. programming of all cells), and results in the ECC reporting it as an operation error.
Thus, the method of the ECC computation described above, has achieved two goals: (1) the erased page became “ECC-legal”, thus simplifying the flash-memory management algorithm; and (2) there is an indication of operation error by the ECC for the case in which flash memory power has been interrupted in the middle of an erasure procedure.
It should be noted that the suggested modification to the ECC computation may be similarly applied to “symmetric” codes (i.e. codes in which both all-zero codewords and all-one codewords are legal). Clearly, in such a case, erased pages will be handled correctly even without this modification.
It should also be noted that, while the example discussed in this application is limited to error detection only, the methods described herein are similarly valid for more complex codes, which support detection as well as correction of errors in the data. As can be shown, the methods may be used for any linear systematic code, even though the methods are more useful when the all-one codeword is not a legal codeword.
A device which incorporates the methods of the present disclosure described above into its operation can be better understood with the aid of FIG. 1 . FIG. 1 shows a simplified schematic diagram of a flash memory device with implemented ECC according to embodiments of the present disclosure. Data bits 20 , located on a host system 22 , are transferred to a flash memory device 24 by a flash memory controller 26 . Flash memory controller 26 stores data bits 20 on flash memory device 24 , and transforms data bits 20 into transformed data bits 28 . Flash memory controller 26 then transfers transformed data bits 28 to an error-correction code 30 , located within flash memory controller 26 . Error-correction code 30 generates parity bits 32 . Parity bits 32 are then transformed into transformed parity bits 34 by flash memory controller 26 . Transformed parity bits 34 are then stored on flash memory device 24 by flash memory controller 26 .
It is noted that both transformed data bits 28 and transformed parity bits 34 may be complements of data bits 20 and parity bits 32 , respectively. It is further noted that the codeword generated by ECC 30 is a concatenation of transformed data bits 28 and parity bits 32 . In alternate embodiments, the functions of flash memory controller 26 , described above, can be performed by software or hardware residing on host system 22 . Furthermore, ECC 30 may be implemented via software within flash memory device 24 or host system 22 .
While the disclosure has been described with respect to a limited number of embodiments, it will be appreciated that many variations, modifications, and other applications of the disclosure may be made. | A method in a data storage device for storing a plurality of data bits into a non-volatile memory includes transforming a plurality of data bits to be stored in a non-volatile memory device to generate a plurality of transformed data bits. The method further includes generating a parity bit corresponding to the plurality of transformed data bits, transforming the parity bit, and storing the plurality of data bits and the transformed parity bit in the non-volatile memory device. Each of the plurality of data bits and the parity bit form an all-one codeword. | 6 |
SUMMARY OF THE INVENTION
With rising energy costs, building owners, as well as building manufacturers and constructors, are seeking ways to provide building designs which reduce the total annual energy consumption required to maintain buildings at a comfortable temperature level. In a large part of the United States the costs of providing air conditioning during the summer months exceeds the cost of heating during the winter months. The area of greatest heat penetration of a typical building is the roof.
The difference between the desired temperature inside a building (such as 78° or less) and the temperature entering the building (as 150° or more) resulting from ambient outside temperature plus solar heat gain is called the cooling load temperature differential, or CLTD. The present invention is directed towards reducing a building's CLTD.
Expressed another way, the present invention is directed towards means of effectively reducing the solar heat gain of a roof. While the concepts of the invention are applicable to buildings in general, the invention is particularly directed to metal buildings of the type frequently employed for offices, warehouses, factories, shopping centers, wholesale and retail outlets, and so forth. Most metal buildings are partially prefabricated and include metal structural members and in most instances, metal coverings for exterior walls and the building roof. Because they can be expeditiously and economically erected, and because of their long life and relative freedom of maintenance, metal buildings have become exceedingly popular in the United States, and their popularity grows each year. One problem, however, with metal buildings has been that of providing adequate insulation to make them economical to air condition in the summer.
The present invention provides a roof, particularly useful in metal buildings, in which plenum chambers are formed between adjacent roof purlins and between the roof and the sheathing placed on the bottom of the purlins. Means is provided for forced movement of air through these plenum chambers to prevent heat buildup. This air movement substantially reduces the temperature to which the building is exposed and thereby significantly reduces the CLTD.
Others have provided forced means for ventilating building attics, and it has long been known that by good attic ventilation, the heat load in a building having an attic, as do most homes, can be reduced. However, metal buildings are traditionally structured without attic space. This is one of the economical features of metal buildings, and the lack of an attic space has precluded the adaptation of the residential type attic ventilation to metal building construction. The answer has been that most metal building manufacturers or contractors have attempted to reduce the CLTD by providing substantially increased insulation thickness between the roof and ceiling. While the industry's standard roll-type insulation serves its highly useful purpose, it is expensive, and decreases in efficiency with additional thickness, if installed in the usual way between the purlins and the roof sheets of a typical metal building roof. The present invention overcomes the problems with the existing type of metal building construction by providing a roof structure having highly improved heat load characteristics.
This invention provides a roof system primarily for metal buildings consisting of a double roof design with rigid insulation, or sheathing which supports insulation, being installed below the roof joists (purlins) as the second roof, thus providing plenum chambers between adjacent purlins and between the roof sheathing and the insulation, with end wall vents to provide a means for entrance of outside air into the plenum chambers, and with fans, connected to the plenum chambers, to provide a means to draw outside air through the plenum chambers and discharge it exteriorly of the building, thereby cooling the plenum chambers and greatly reducing the solar heat gain before it enters the building's interior area.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective external view of a typical metal building, partially cut away, showing how the present invention is adapted to the roof structure for improved cooling load reduction by using end wall discharge fans.
FIG. 2 is a perspective view, as in FIG. 1, but showing the arrangement wherein the fans utilized to move air through the roof plenum are located on the roof of the building.
FIG. 3 is a partial cross-sectional view taken along the line 3--3 of FIG. 2.
FIG. 4 is a partial cross-sectional view taken along the line 4--4 of FIG. 1.
FIG. 5 is a partial cross-sectional view of the building roof taken along the line 5--5 of FIG. 1.
DETAILED DESCRIPTION
Referring to the drawings and first to FIG. 1, an external view of a typical metal building is shown partially cut away and showing how the principles of this invention are adapted to the building design. The building includes a first end wall 10 and opposed second end wall 12, the first end wall 10 not being seen in FIG. 1, and side walls 14 and 16, the opposed side wall 16 not being seen. The building includes a typical gabled roof generally indicated by the numeral 18.
FIG. 2 shows a building as in FIG. 1 but including a different fan arrangement for a positive movement of the air through the roof structure, particularly useful on longer buildings, as will be described in detail subsequently.
Referring to FIGS. 4 and 5, which are cross-sectional views of the metal building as shown in FIGS. 1 and 2, more details of the invention will be seen. Turning first to FIG. 5, the building side wall 14 is shown. Supported by structural members not indicated in FIG. 5 are spaced apart roof purlins 20, 22, and eave strut 24. Eave strut 24 is at the side of the roof structure immediately above the side wall 14 and is C-shaped while typical roof purlins 20, 22 are Z-shaped.
Each of the purlins 20, 22, and eave strut 24 include a top edge designated by the letter A and a lower edge designated by the letter B. Positioned on the purlin top edges is roof sheathing 26 which provides a leak-proof and a substantially air-tight roof structure. In metal building construction, the roof sheathing 26 is typically ribbed type metal attached to the purlin upper edges. The outer edge of the roof sheathing may include a gutter 28.
In order to prevent the penetration of solar heat, to which the roof sheathing is constantly exposed, building erectors typically spray or install insulation against the lower surface of the roof sheathing. While this is effective to a limited extent, nevertheless, the interior 30 of the building is still subjected to the penetration of heat as the roof 26 becomes exceedingly hot due to direct exposure with the sun. The temperature of the roof sheathing 26 may reach or exceed 157° after long exposure to direct sunlight. If it is intended to keep the interior 30 of the building at a maximum of 78°, this means a cooling load temperature differential (CLTD) of 79°.
By the present invention, this CLTD may be reduced by as much as 60 to 90%, depending upon outside temperature.
To the lower edges 20B, 22B, 24B of the purlins and eave strut 20, 22, and 24, a ceiling sheathing 32 is attached. This may be in the form of plywood, insulation board, metal sheathing, or the like. The ceiling sheathing 32 on the lower edges of the purlins combined with the roof sheathing 26 on the upper edges of the purlins means that a plenum 34 is provided between each adjacent pair of paralleled purlins.
Referring to FIGS. 3 and 4, which are taken at right angles to the view of FIG. 5 and parallel to the purlins, a method whereby the plenum areas 34 between each adjacent pair of purlins may be employed to reduce the CLTD of the building is illustrated. The first end wall 10 which is shown to include column 36, is provided with a rake trim 38 having a lower vent or bird screen 40. In this manner the rake trim 38 provides communication between the outside air and the plenum 34 formed between adjacent purlins. At the opposite end wall 12 of the building, as shown in FIG. 4, a fan unit generally indicated by the numeral 42 is provided. In the illustrated arrangement, the fan unit includes a fan housing 44 which is attached to the second end wall 12 and provides a fan inlet 46 communicating with the plenum 34 formed between adjacent purlins. End wall 12 has an opening 48 therein which forms the fan exhaust to the building exterior. The opening 48 includes a louver 50 which may be of the self-closing type, that is, when air is not moving through the louvers, it automatically closes.
Mounted within fan housing 44 is a fan 52 driven by motor 54.
When the fan motor 54 is energized, air is drawn in through the rake trim inlet 40 and passes through the plenums 34, down through the fan inlet 46 and out the fan exhaust opening 48. Thus, the fan 52 serves to move air constantly, when the fan is energized, through the plenums 34 to effectively maintain the air in the plenums at a temperature only slightly above the outside ambient air temperature.
The second end wall 12 includes a rake trim 56 which does not have an opening, that is, no air is permitted to enter into the plenums 34 at the second end of the building, thereby permitting air movement only through the full length of each of the plenums.
The fan arrangement of FIG. 4 is utilized when the length of the building is not great, that is, when the resistance of movement of air through the full length of plenum 34 can be easily handled by fan 52. This arrangement is shown in FIG. 1 in which a plurality of fans covered by louvers 50 are employed. When the building is longer so that the resistance to movement of air for the full length of the plenums would require excess capacity fans, the arrangement can be made as illustrated in FIGS. 2 and 3 in which the roof mounted fan, generally indicated by the numeral 58, is employed. Fan 58 includes a housing 60, which tapers outwardly and downwardly, the lower end of which is supported on the roof sheathing 26 and provides a fan outlet 62 having communication with a plurality of plenums 34. Fan 58 includes a motor 64 which drives blades 66. A canopy 68 covers the fan blade 66 and provides an annular fan exhaust opening 70. When the fan motor 64 is energized, air is drawn from both ends 10 and 12 of the building, as shown by the arrows in FIG. 2. When a roof mounted fan 58 is utilized, the rake trim at both ends of the building must be of the type shown in the left-hand portion of FIG. 3 identified by the numeral 38, that is, it must have a vent 40. By the central mounting of fans 58, air is drawn in both directions from the ends of the building through the plenums 34 and exhausted to reduce the CLTD of the building.
As shown in FIG. 4, a thermostatic control 72 will be placed in electrical series with motor 54. A remote probe 74 is positioned in a plenum 34. In this manner, fan 52 can be regulated by control 72 to be energized when the temperature in plenum 34 exceeds a preselected level, such as 85°. Fan 52 will thereby be energized to move the air through the plenums 34 until the temperature drops below the preset minimum level.
In like manner, as shown in FIG. 3, a control 76 is in electrical series with motor 64 of roof mounting fan 58, actuated by a remote probe 78 positioned in the plenum 34 to serve the same purpose.
Assuming the outside temperature on a sunny day is 99° ambient, the roof sheathing 26 of the building may, as previously indicated, approach a temperature of 157°. If it is required that the interior 30 of the building be maintained at a temperature not exceeding 78°, this means that there is a CLTD of 79°. Even if insulation is applied to the underneath surface of the roof sheathing 26, as is the current practice, a part of the CLTD depending upon inplace insulation rating, will enter the interior 30 of the building.
By the application of the principles of this invention, fans, whether the wall mounted fan 52 or the roof mounted fan 58, are employed which serve to move air through the plenums 34 maintaining the temperature to which the upper surface of the ceiling sheathing 32 is exposed to substantially that of the ambient air temperature. This temperature will normally be slightly above the ambient air temperature since there is a limit to the quantity of air which can be economically moved through the plenums, but for all practical purposes, the air will be only a few degrees above ambient, for instance, 103° under the stated conditions. Thus, the CLTD across the ceiling sheathing 32 is only the difference between 103° and 78°, that is, 25°, compared to a CLTD of 79°. This represents a 68% reduction in the CLTD by the application of the principles of this invention.
As the outside ambient temperature drops, the differential CLTD will also drop, but the efficiency of this invention will increase because the plenums are being cooled by outside air which is nearer the same temperature as the desired inside temperature.
Assuming a sunny, ambient 80° with a roof sheathing temperature of 133° and a desired interior 30 temperature of 78°, by application of the principles of this invention, the plenum air may be only 83°. Thus, the CLTD across the ceiling sheathing 32 is only the difference between 83° and 78°, that is, 5°, compared to a CLTD of 55°. This represents a 91% reduction in the CLTD by application of the principles of this invention. Stated another way, the building's insulation efficiency is 55:5 or 11:1 under this condition.
When evening comes, the CLTD across roof sheathing 26 will decrease, and when the temperature of the air in the plenum chambers drops below that preset for the control 72 and 76 as detected by probe 74 and 78 respectively, the fans will be de-energized.
It is understood that the roof design of this invention is not intended to completely eliminate the usefulness of insulation. Roof 26 may be insulated, if desired, and, more importantly, the ceiling sheathing 32 will be insulated, and for this purpose, angles 80 (FIGS. 3 and 4) may be installed above the ceiling sheathing 32 to serve to provide a boundary for insulation 82. This insulation may be of various types, including blown-in insulation, bats of spun glass, or plastic foam. Insulation 82 serves to insulate the building interior 30 and is particularly useful in winter conditions when heating rather than air conditioning is required.
Thus, it can be seen that the roof design set forth herein effectively and substantially reduces the CLTD to which the interior of the building is subjected. By the provision of short depth plenums 34 formed between adjacent purlins and between the ceiling sheathing and roof sheathing, relatively small amounts of air need be moved to achieve a substantial CLTD reduction.
While the invention has been described with a certain degree of particularity, it is manifest that many changes may be made in the details of construction and the arrangement of components without departing from the spirit and scope of the disclosure. It is understood that the invention is not limited to the embodiments set forth herein for purposes of exemplification, but is to be limited only by the scope of the attached claim or claims, including the full range of equivalency to which each element thereof is entitled. | A roof structure for a building having end walls and side walls, the structure providing reduced air conditioning loads for the building, the roof having spaced apart purlins, roof sheeting affixed to the top edge of the purlins, ceiling sheathing affixed to the bottom edge of the purlins providing plenum areas between adjacent purlins and between the roof and ceiling sheathing, vents at one end wall providing means for entrance of outside air into one end of the plenum areas, and fan means connected with the plenum areas to draw air through the plenum areas and discharge it exteriorly of the building, thereby cooling the plenum areas and reducing the effective heat load of the building ceiling. | 4 |
The present invention discloses an ostomy device comprising an adhesive wafer, wherein said adhesive wafer comprises means for preventing deformation and tearing when the adhesive wafer is removed from the skin. In particular, the present invention relates to adhesive wafers formed of soft adhesives.
BACKGROUND
Collecting devices for collecting bodily waste, ostomy appliances, wound or fistulae drainage bandages or devices for collecting urine are usually in the form of a receptacle, e.g. a bag, pouch or tube for receiving the waste, connected to an adhesive wafer that can be attached to the user's skin. The wafer is typically in the form of a backing layer coated on the skin-facing surface with an adhesive layer, and the wafer may further be provided with an aperture for accommodating the body opening. The size and shape of said aperture can often be adapted individually to fit the anatomy of the patient.
One of the crucial parts of such devices is the adhesive wafer. The wafer should be able to fit leak proof around the body opening and have good adherence to the skin without unintended detachment from the skin, but at the same time the wafer should be easy to remove again without damaging the skin. Furthermore, the wafer should be able to follow the movements of the body and be comfortable to wear. The components of the wafer, the adhesive and the backing layer determine these properties.
Pressure sensitive adhesives have for a long time been used for attaching medical devices, such as ostomy appliances, dressings (including wound dressings), wound drainage bandages, fistula drainage devices, devices for collecting urine, orthoses and prostheses to the skin.
The adhesive of such devices is usually a hydrocolloid adhesive coated in a relatively thick layer on a backing layer, and combined with the fact that this adhesive is rather stiff, the device may be inflexible and bulky to wear.
Ostomy wafers with softer adhesives are already known. These have been developed in order to solve some of the above problems such as inflexibility and bulkiness. Such soft adhesives may for example be silicone adhesives. Although such adhesives solve problems regarding comfort due to their softness they may be complicated to remove from the skin. Being soft and flexible, they stretch and are difficult to control. In some cases they may even tear during removal from the skin.
Thus, there exists a need to reduce the risk that the adhesive wafer is greatly deformed or torn when removed from the skin.
DETAILED DESCRIPTION OF THE PRESENT INVENTION
The invention discloses an adhesive wafer for removable placement on the skin surface of a mammal, the adhesive wafer comprising a backing layer whereon at least a first adhesive is disposed in a first adhesive layer, the adhesive wafer extending mainly in one plane from a center of the adhesive wafer in a radial direction towards an annular peripheral edge of the adhesive wafer, the radial extent being larger than the axial extent, wherein a pulling tab is provided at the annular peripheral edge and that reinforcement means are provided only between the center and the pulling tab.
This allows the adhesive wafer to maintain most of its flexibility, while providing an area of the adhesive with improved resistance to deformation and thereby tearing when removing the adhesive wafer from the skin. The reinforcement means are advantageously arranged between the pull tab and the center of the adhesive wafer in a radial direction towards the pull tab. The pull tab provides a clear indication of where to pull when removing the wafer and also facilitates gripping, while the reinforcement means provides the added support to allow easy removal of the wafer.
The reference to the center of the adhesive wafer should be understood broadly as a central point or area of the wafer which would be considered central when considering the wafer either geometrically, by mass or otherwise indicates the middle of the wafer. For example, if considering an ostomy base plate the hole for receiving the stoma would be considered the center of the adhesive wafer. The reinforcement means does not necessarily have to extend all the way from the center to the tab, but may in some embodiments extend partly in the radial direction from the center of the first adhesive layer towards the peripheral edge of the adhesive wafer.
In one embodiment, the reinforcement means are provided as an area of the first adhesive having a larger thickness than the adjacent first adhesive layer. This is a simple way of providing improved strength in an area and thereby reducing the risk of tearing.
In another, or additional, embodiment, the reinforcement means are provided in the form of a material having greater tear strength than the adjacent first adhesive layer and the backing layer. This allows for very high resistance to tearing because materials may be chosen that are very tear resistant while at the same time being highly flexible.
One such material may for example be a mesh. Providing a mesh between the backing layer and the adhesive would have the advantage that manufacturing was facilitated as the openings in the mesh would allow the adhesive to effectively bond to the backing layer.
In some embodiments of adhesive wafers, two or more different adhesives are used in order to achieve the different advantages of these adhesives. Thus, in another embodiment, a second adhesive is disposed on the first adhesive layer as a second adhesive layer, the second adhesive layer extending only partly from the center of the adhesive wafer towards the peripheral edge of the adhesive wafer, wherein the reinforcement means is thicker than the first adhesive layer. Typically it is the thinnest adhesive layer which has a risk of tearing. Thus, by at least providing reinforcement with a thickness greater than the thinnest layer, resistance to tearing is improved.
In other embodiments the reinforcement means may for example comprise at least one string extending in a radial direction between the center and the pulling tab. The at least one string may have a lower elasticity than the part of the wafer which do not extend between the center and the pulling tab.
Thus the string determines the deformation and/or tear strength of the wafer in the area between the pull tab and the center of the wafer.
In another aspect the present invention relates to a kit comprising an adhesive wafer for removable placement on the skin surface of a mammal, the adhesive wafer comprising a backing layer whereon at least a first adhesive is disposed in a first adhesive layer, the adhesive wafer extending mainly in one plane from a center in a radial direction towards an annular peripheral edge, the radial extent being larger than the axial extent, wherein a pulling tab is provided at the annular peripheral edge, and an adhesive label for attachment to the adhesive wafer between the pull tab and the center.
By providing the reinforcement means as a separate adhesive label the user can apply the label before removal of the wafer. Thus the increased material and stiffness that the reinforcement means may add to the wafer can be avoided during use.
FIGURES
FIG. 1 illustrates an adhesive wafer as described herein.
FIG. 2 shows in section the adhesive wafer of FIG. 1 along line II-II.
DETAILED DESCRIPTION
The figures show an adhesive wafer 1 for application to the skin surrounding a stoma. The adhesive wafer has a central through-going hole 2 which can be cut into shape if necessary in order to receive a stoma.
The adhesive wafer is formed of a backing layer 3 , whereon an adhesive 4 is arranged on the proximal side. In use the proximal side is the side facing the user, thereby exposing the adhesive to the skin and adhering it thereto. The distal side of the adhesive wafer faces away from the skin providing a non-adhesive surface preventing that unwanted articles, such as clothing, adheres to the wafer.
The distal side is also provided with collection means (not shown). Such collection means may be a collecting bag attached directly to the backing layer. However, other arrangements such as coupling elements for allowing a detachable connection to a collecting bag may be provided. Such arrangements have not been shown in order to simplify the illustration and also because these are already well known in the art and not part of the present invention.
A pull tab 7 is provided along the periphery of the adhesive wafer. The pull tab 7 provides the user with means for easily getting hold of the adhesive wafer in order to remove it from the skin.
The adhesive 4 is formed of two adhesive layers. A first adhesive layer 5 is disposed on and covers the proximal side of the backing layer 3 . A second adhesive layer 6 is disposed on the proximal surface side of the first adhesive layer. The second adhesive layer encircles the through-going hole and has a smaller radial extent than the first adhesive layer. By providing two adhesive layers, different properties can be accentuated. For example, the second adhesive layer 6 can be formed of an adhesive having high hydrocolloid content. This allows it to absorb moisture and small amounts of output from and around the stoma. The first adhesive layer can however be formed to have a high tack giving it a higher resistance to peeling.
In order to provide a comfortable feel when wearing the adhesive wafer, and further prevent pressure wounds and the like, the adhesive wafer is made as soft as possible. By ‘soft’ is meant that the adhesive wafer is highly flexible and stretchable in order to follow the movement of the skin whereon it is adhered. A number of elements can be manipulated in order to provide such a ‘soft’ feel. For example the backing layer 3 is formed of a flexible and stretchable material and the adhesive 4 is made as thin as possible.
However, as the softness of the adhesive wafer is increased the adhesive wafer becomes more difficult to remove from the skin. This is due to the high stretchability of the adhesive wafer which results in that instead of being easily removed, the adhesive wafer stretches and deforms making it difficult to handle. In some cases, the adhesive wafer simply tears apart when the user tries to remove it from the skin.
Thus, in order to prevent excessive deformation or even tearing, a reinforced area 8 has been provided. In the shown embodiment, the reinforced area 8 is provided by increasing the thickness of the first adhesive layer in some areas. In particular the inner annular area 9 of the first adhesive layers has been made thicker and a lip 10 in the form of a strip of adhesive having increased thickness is provided between the inner annular area and the pulling tab 7 .
Thus, the stability of the adhesive wafer is increased allowing it to be removed by pulling the pull tab 7 without the risk of excessively deforming or tearing the adhesive wafer while at the same time maintaining most of the softness of the adhesive wafer.
As discussed previously, other means of providing stability when pulling the pull tab 7 may be provided. Thus, instead of increasing the thickness of the material a reinforcement material could be provided between the through-going hole and the pull tab. The reinforcement material could for example be in the shape of a mesh and it could be dimensioned so as to have a desired stretchability so that it can be elongated to a certain extent without tearing. | The present invention discloses an ostomy device comprising an adhesive wafer, wherein said adhesive wafer comprises means for preventing deformation and tearing when the adhesive wafer is removed from the skin. In particular, the present invention relates to adhesive wafers formed of soft adhesives. | 0 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority of German Application No. 102 04 993.9, filed Feb 5, 2002, the complete disclosure of which is hereby incorporated by reference.
BACKGROUND OF THE INVENTION
[0002] a) Field of the Invention
[0003] The invention is directed to an arrangement for machining workpieces by means of a laser, particularly for cutting, perforating, notching, engraving, drilling and inscribing workpieces with three-dimensional structures of different sizes. It can also be used advantageously for removing layers from such workpieces.
[0004] b) Description of the Prior Art
[0005] Arrangements for machining a workpiece by means of a laser basically comprise a laser, a device for guiding the laser beam to the workpiece and a device for holding the workpiece. For processes in which a relative movement (forward feed) must be carried out between the laser beam, as tool, and the workpiece (e.g., cutting, perforating, ablating), this relative movement is usually realized by the device for guiding the laser beam, while the workpiece is held so as to be stationary.
[0006] Various basic principles are known for such devices for guiding the laser beam to the stationary workpiece surface.
[0007] For machining of large-area workpieces in particular, arrangements are known in which a laser head focusing the laser beam can be moved freely in a parallel to the workpiece surface by means of an overhead gantry or frame. The laser beam travels from the laser to the laser head by way of an articulated mirror arm. This is advantageous in that, when suitably dimensioned, a frame of this kind can guide the laser beam also over very large workpiece surfaces. Its disadvantages consists in a large space requirement, limited machining speed, particularly when the machining direction is changed often, and the fact that it is applicable exclusively on plane workpiece surfaces.
[0008] Arrangements in which a laser head is arranged at a robot arm which is freely movable in three dimensions are also known for machining large workpiece surfaces. In this case also, the laser beam, is guided to the laser head by an articulated mirror arm. The size of the workpiece surface to be machined is limited only by the free space for the movement of the robot arm and mirror articulation arm. The inertia of the mechanics of the robot arm and of the articulated mirror arm also allow only a limited machining speed.
[0009] In both solutions, it is known to arrange at the laser head a gas nozzle through which a flow of gas is directed to the surface to be machined in order to prevent flames which lead to unwanted soot deposits and to prevent depositing of melted material. Since the laser radiation exits the laser head in a fixedly defined direction and is guided over the workpiece surface at a defined distance, the gas nozzle is mounted on the laser head at a fixed angle to the laser beam such that the laser beam and the gas jet exiting from the gas nozzle are always directed to the same point on the workpiece surface.
[0010] It is known to use optical beam deflecting units, also known as laser scanners, for machining small, plane surfaces. The beam is guided by the tilting of mirrors. This is advantageous because of the high speed that can be achieved and due to the accurate precision of the beam deflection. It is disadvantageous that the laser beam can only sweep over a small spatial area. A combination of such arrangements with a gas feed to the machining location is not known.
[0011] Therefore, the only solutions used in the prior art for arrangements in which workpieces with large surfaces extending in three dimensions are to be machined are those in which the laser beam is guided along the desired machining line on the workpiece surface by means of an articulated mirror arm fastened to a robot arm.
OBJECT AND SUMMARY OF THE INVENTION
[0012] It is the primary object of the invention to provide an arrangement for machining workpiece surfaces extending in three dimensions in which a flow of gas is directed to the machining location and which permits a faster machining speed compared to conventional arrangements independent of the extent and shape of the machining line.
[0013] This object is met for an arrangement according to the invention, the arrangement being for machining workpiece surfaces extending in three dimensions by a laser comprising a stationary laser, an articulated mirror arm, a robot arm connected to a robot for guiding the second end of the articulated mirror arm, a holding device for fixing a workpiece, at least one gas nozzle by which a flow of gas is directed to the workpiece surface and a control device for controlling the robot arm, and in that a laser scanner is fastened to the robot arm and is connected to the articulated mirror arm in such a way that the beam exiting from the second end of the articulated mirror arm is coupled into the laser scanner and the gas nozzles are arranged at the laser scanner so as to be movable in such a way that they can be oriented to the workpiece surface by a gas nozzle propulsion communicating with the control device, so that the gas flow and the radiation exiting from the laser scanner via an exit face coincide at a point on the workpiece surface.
[0014] The invention will be described more fully in the following in an embodiment example with reference to a drawing.
BRIEF DESCRIPTION OF A DRAWING
[0015] FIGURE 1 shows a schematic view of a construction of an arrangement.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0016] The arrangement shown in FIGURE 1 essentially comprises a laser 1 which is mounted in a stationary manner, a robot arm 2 which is fastened to a robot shown in the drawing only as a fixed bearing, an articulated mirror arm 3 , a laser scanner 4 , a control device 5 , a gas nozzle propulsion unit 6 , at least one gas nozzle 7 , and a holding device 8 .
[0017] With respect to the connections between the devices, the thick solid lines represent mechanical connections, the thin dotted lines show signal connections, and the thick lines with multiple dots represent optical connections.
[0018] The stationary laser 1 is mechanically and optically connected to the first end of the articulated mirror arm 3 , the second end of the articulated mirror arm 3 being fixedly connected to the free end of the robot arm 2 . The second end of the articulated mirror arm 3 through which the beam coupled in by the laser 1 exits the articulated mirror arm 3 is accordingly freely movable in three dimensions. The laser scanner 4 which is fixedly coupled to the second end of the articulated mirror arm 3 optically and mechanically on the input side is likewise arranged at the free end of the robot arm 2 . The gas nozzle propulsion unit 6 and at least one gas nozzle 7 are fastened to the laser scanner 4 . A signal line provides a control connection from the laser 1 , the robot arm 2 , the laser scanner 4 and the gas nozzle propulsion unit 6 to the control device 5 .
[0019] The radiation emitted from the laser 1 is coupled into the first end of the articulated mirror arm 3 and exits the articulated mirror arm ( 3 ) by the second end at a point within the space above a workpiece fixed to the holding device ( 8 ), which point is determined by the spatial position of the free end of the robot arm ( 2 ). Upon exiting the articulated mirror arm ( 3 ), the radiation is coupled into the laser scanner ( 4 ), where the beam can be deflected by the mirror elements around the above-mentioned point in two or three spatial directions. The beam is guided in the desired manner for machining the workpiece by means of a coordinated control of the spatial position and speed of the articulated mirror arm 3 and mirror elements of the laser scanner 4 . The position of the beam when striking the workpiece surface is accordingly determined by a coordinated superposition of the beam control in the articulated mirror arm ( 3 ) and in the laser scanner ( 4 ). The person skilled in the art is familiar with the particulars of beam control in an articulated mirror arm ( 3 ) and laser scanner ( 4 ). The gas nozzle 7 is movably arranged at the laser scanner 4 and follows the laser beam by means of the gas nozzle propulsion unit 6 , so that the direction of the gas flow intersects with the laser beam on the workpiece surface in the respective machining location. A plurality of gas nozzles 7 are advantageously arranged about the exit face of the laser beam at the laser scanner 4 . In a conventional laser scanner 4 in a square arrangement around the exit face, for example, the gas nozzles 7 can be arranged at each of the four comers of the laser scanner. More than four nozzles can also be arranged in a ring shape around the exit face.
[0020] The inventive combination of an articulated mirror arm 3 and a laser scanner 4 with a gas nozzle propulsion unit 6 and gas nozzles 7 makes it possible, by coordinated simultaneous or alternate control, to guide the laser beam and gas flow to the machining location in an optimal manner depending on the size and shape of the workpiece and depending on the size and contour of the machining surface (e.g., for ablating) or machining line (e.g., for cutting or perforating).
[0021] The uniformity with which the gas flow strikes the machining location increases as the number of gas nozzles 7 arranged about the exit face in a centrally distributed manner increases.
[0022] In principle, an arrangement according to the invention can be operated in three machining modes:
[0023] 1. The robot arm 2 moves the laser scanner 4 to a first machining position and remains stationary during machining. The machining surface or machining line is machined only by controlling or deflecting the mirrors in the laser scanner 4 . The gas nozzles 7 are deflected by the gas nozzle propulsion unit 6 in such a way that the gas flow is directed to the machining location, i.e., to the precise point on which the laser beam also impinges. The robot arm 2 subsequently moves the laser scanner 4 to a second machining position, where the machining process is repeated (stop-and-go operation). During machining, the beam is guided on the workpiece surface exclusively by means of the laser scanner 4 . An operation of this kind is advantageous for cutting hole contours, for example.
[0024] 2. The laser scanner 4 is moved over the workpiece surface continuously by the robot arm 2 and, in addition, the laser scanner 4 deflects the beam in one, two or three directions (flying motion operation). During the machining, the beam is accordingly guided by a coordinated time-controlled and position-controlled deflection of the articulated mirror arm 3 and mirror elements of the laser scanner 4 . The spatial guidance (machining contour) and timed guidance (machining speed) of the laser beam moved by the laser scanner 4 is controlled in accordance with the movement speed of the robot arm 2 which guides the articulated mirror arm 3 . This machining mode is particularly suitable for longer non-straight machining lines, e.g., a sinusoidal line.
[0025] 3. The robot arm 2 is guided over the workpiece surface continuously and the laser scanner 4 keeps the beam stationary (motionless operation). The beam is guided exclusively by means of the robot arm 2 . This mode is provided particularly for machining very long, large contours.
[0026] Circles with a diameter of 10 mm, for example, can be produced at a speed of 10 ms with an arrangement according to the invention compared to a speed of 1 s with an arrangement having only one robot arm for guiding the beam. Rectangles measuring 10 mm ×10 mm can be machined in 40 ms instead of 1.3 s.
[0027] While the foregoing description and drawings represent the present invention, it will be obvious to those skilled in the art that various changes may be made therein without departing from the true spirit and scope of the present invention.
[0028] REFERENCE NUMBERS
[0029] [0029] 1 laser
[0030] [0030] 2 robot arm
[0031] [0031] 3 articulated mirror arm
[0032] [0032] 4 laser scanner
[0033] [0033] 5 control device
[0034] [0034] 6 gas nozzle propulsion unit
[0035] [0035] 7 gas nozzles
[0036] [0036] 8 holding device | An arrangement for machining workpieces by a laser, particularly for cutting, perforating, notching, engraving, drilling and inscribing workpieces with three-dimensional structures of different sizes. The laser beam is directed to the workpiece, which is fixed on a holding device, by means of a robot-guided articulated mirror arm and a laser scanner. The laser beam is guided by a coordinated time-controlled and position-controlled deflection of the articulated mirror arm and of the mirror elements of the laser scanner. | 1 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to specialized vehicles and more particularly to a special vehicle for dispensing molten asphalt into containers. 2. Description of the Prior Art
As is well known in the art molten asphalt is employed for various jobs in the construction arts such as for seal coating roadways, runways and the like, and also for comparatively small jobs such as the filling of cracks and expansion joints in paved surfaces, and various spot applications such as on paved surfaces, roofs, and the like.
In the relatively large jobs, such as the above mentioned seal coating of paved surfaces, where large quantities of molten asphalt are to be used, the molten asphalt is placed in special transport trucks at the asphalt plant and delivered directly to the job site where it is transferred either to interim storage tanks or directly to heated spray applicator trucks. In some instances, the molten asphalt is mixed at the job site with special additives such as shredded rubber, prior to being applied to the paved surface. At any rate, such a procedure must be accomplished rather rapidly to prevent excessive cooling of the molten asphalt, to keep the needed interim storage facilities to a minimum, and to keep the equipment and labor costs to a minimum. Even when this procedure is most efficiently accomplished, it is an expensive matter and as such cannot be economically justified on the comparatively smaller jobs due to the smaller quantities of material needed, the slow and often interrupted application schedules and the like.
Therefore, it is a common practice to place molten asphalt, or molten asphalt compositions, in manually handleable containers at a manufacturing facility and ship the desired quantity to a job site on an as needed and when needed basis. When the asphalt is needed at a job site, the containers are torn open and the asphalt, which has since cooled and thus, solidified, is placed in a heating vessel which is usually a tank that is an integral part of the mechanism which is to be used to apply the asphalt. When the desired temperature of the molten asphalt is reached, normally a minimum of about 275° F., it is applied in accordance with procedures suitable for the particular job.
The commonly used prior art method for placing the asphalt into manually handleable containers is in the form of an elongated conveyor system. At a first station of the prior art conveyor system, a plastic package or liner is inserted into an open corrugated cardboard box and transported by the conveyor to a second station below the outlet of a stationary molten asphalt dispensing unit. At this second station, the dispensing mechanism deposits a predetermined amount of the molten asphalt, usually about sixty pounds, in each container which is passed thereunder. After such filling, the containers are transported to a third station on the conveyor system where the asphalt filled packages and their containers are closed, and from there they are transported to the last station where they are manually off-loaded from the conveyor system and placed on pallets for subsequent shipping.
The prior art method described above has several drawbacks. In the first place, the off-loading and stacking tasks must be accomplished without excessive delays so as not to halt production. Therefore, the asphalt in the containers is still in the molten state when the off-loading and pallet stacking operations need to be accomplished. The molten state of the asphalt rules out the use of all but the most sophisticated mechanized equipment, and the costs of such equipment cannot be justified in operations of this sort. Therefore, the asphalt containers are manually off-loaded and stacked on the pallet, and this is a very arduous and uncomfortable job due to the weight of the asphalt containers and the heat radiating therefrom.
The second, and most serious, problem with the prior art conveyor system for containerizing asphalt involves the lack of portability of the equipment. High shipping costs dictate that a prior art conveyor system cannot be economically used to containerize asphalt for use outside of a given area. Thus, a prior art conveyor system is intermittently used in that it is normally capable of satisfying the needs of its immediate area with, for example, two days of operation per week. Providing containerized asphalt for areas outside of the immediate vicinity of an existing prior art conveyor system involves either paying the high shipping costs, or building and manning other conveyor systems which will also be intermittently operated.
The above described drawbacks and shortcomings of the commonly used prior art asphalt containerization system have been overcome to a great extent by a new method which is fully disclosed in a pending U.S. Patent Application entitled: METHOD FOR CONTAINERIZING ASPHALT, Ser. No. 144,301, filed on Apr. 28, 1980 by J. Ronald Robinson, with the application having the same assignee as the present invention.
Briefly, this new method comprises the placement of a first tier of open top containers in side-by-side relationship on each of a plurality of pallets which are arranged in a linearly aligned juxtaposed relationship. Then an asphalt dispenser vehicle is slowly moved in a path which is parallel to the aligned pallets so that an asphalt dispenser hose provided on the vehicle may be moved from container to container for filling purposes. When each container has been filled in this manner and subsequently closed, a second tier of containers is placed on each pallet, and the dispenser vehicle is again moved in the parallel path for filling of the containers of the second tier. When the second tier of containers are filled and closed, the steps of this method are again repeated for a third tier, and if desired, for additional tiers.
In developing and testing the above described method for containerizing asphalt, it was found that the conventional well known asphalt handling vehicles, such as highway transport trucks, spray applicator trucks and the like, could be used provided they had some simple modifications made thereto. However, some of the inherent characteristics of such vehicles are beyond reasonable modification and those characteristics make their use in this application a very slow, awkward and costly operation.
The above described vehicles are very awkward to use due to the fact that the vehicle's operator is located in a cab at the front of the vehicle and the asphalt is being dispensed from a hose at the back of the vehicle. It is very difficult, if not impossible, for the vehicle's operator to see what is going on; he can't tell when it is time for him to move and he can't tell how far he should move. In many vehicles of this type, the controls for the asphalt pump, and other such equipment, are located in the driver's compartment, and thus the operator who can't see what is going on is the one who must control the flow of the asphalt. Further, such vehicles are equipped with two engines, one to move the vehicle and another to run asphalt mixing augers, dispensing pumps, and the other special components provided on this type of vehicle. When used for their intended purposes, such two engine configurations are highly justifiable. However, in this highly specialized application, it is very costly to operate one engine to handle the asphalt dispensing operations and operate a second engine which moves the vehicle a few feet and then idles until several containers are filled, and then moves the vehicle a few more feet.
Therefore, a need exists for a new and useful asphalt dispenser vehicle which is especially designed for use in containerizing molten asphalt.
SUMMARY OF THE INVENTION
In accordance with the present invention, a new and useful asphalt dispenser vehicle is disclosed for the special purpose of dispensing molten asphalt, or molten asphalt compositions, into a plurality of manually handleable containers.
The vehicle has an asphalt containing tank carried on a suitable frame which is provided with the usual drive wheels at the back and steerable wheels at the front. An engine is provided for driving hydraulic pumps, which, in conjunction with suitable hydraulic motors and control devices, provide power for driving the vehicle, operating a materials agitating auger in the tank and operating an asphalt delivery pump at the rear of the vehicle.
With the exception of secondary vehicle functions, all of the major functions of the vehicle are accomplished hydraulically with power supplied by a single power source in the form of an internal combustion engine.
To facilitate accomplishment of the highly specialized usage of this vehicle, the operator is seated at the rear of the vehicle immediately behind one set of the drive wheels and all of the controls for moving and steering the vehicle as well as dispensing the asphalt are located adjacent the driver's seat.
Accordingly, it is an object of the present invention to provide a new and useful asphalt dispenser vehicle.
Another object of the present invention is to provide a new and useful economically operated asphalt dispenser vehicle which is especially designed to facilitate the dispensing of molten asphalt into a plurality of manually handleable containers.
Another object of the present invention is to provide a new and useful asphalt dispenser vehicle which is designed to move slowly along a path beside a specially arranged plurality of containers while molten asphalt is being dispensed from the vehicle into the containers.
Another object of the present invention is to provide a new and useful asphalt dispenser vehicle of the above described character which utilizes a single power source for moving the vehicle and handling the molten asphalt.
Another object of the present invention is to provide a new and useful asphalt dispenser vehicle of the above described character wherein the single power source is an engine which runs hydraulic pumps which in conjunction with hydraulic motors, pumps, and controls, provide for moving the vehicle, agitating the asphalt and delivering the asphalt.
Still another object of the present invention is to provide a new and useful asphalt dispenser vehicle of the above described character where all of the major functions of the vehicle are controlled by an operator who is located at a rear corner of the vehicle where he can see what is required for accomplishing the desired asphalt dispensing operations.
The foregoing and other objects of the present invention, as well as the invention itself, may be more fully understood from the following description when read in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a diagrammatic plan view of the asphalt dispenser vehicle of the present invention with portions thereof arranged in schematic form, and other portions broken away to illustrate the various features of the vehicle.
FIG. 2 is a perspective view showing the rear and one side of the vehicle of the present invention.
FIG. 3 is a perspective view showing the front and one side of the vehicle of the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring more particularly to the drawings wherein the asphalt dispenser vehicle of the present invention is indicated in its entirety by the reference numeral 10.
The vehicle 10 includes a suitable frame 12 which is provided with the usual rear wheels 14 and 16 which are driven by a conventional differential 18 which has a power input drive shaft 20. The front wheel 22 of the vehicle are mounted in the usual manner for steering of the vehicle. Due to the unusual remote positioning of the vehicle's operator, as will hereinafter be described, steering cannot be conveniently accomplished in the conventional manner. Therefore, an electrically operated linear actuator 24 is mounted on the vehicle's frame 12 at the left front corner thereof, and its extensible/retractable output shaft 25 is connected to the vehicle's steering linkage (not shown) in the normal manner. Electric power for operation of the linear actuator 24 and for operation of the vehicle's engine 28, is provided by a suitable battery 30 carried on the frame 12 adjacent the actuator. A control switch 32 is provided for selective operation of the linear actuator 24 with the switch being located adjacent the operator's seat 34 at the left rear corner of the vehicle 10.
A large capacity materials tank 36 having a top fill port 37 and an asphalt output port 38 at its rear is mounted on the frame 12 for receiving asphalt from an external source (not shown) and for receiving any additives which may be desirably added thereto, such as shredded rubber. The asphalt received in the tank 36 will be in the molten state and will require agitation to maintain a constant temperature throughout the material and for mixing any additives with the asphalt. Also, agitation is employed to expedite the remelting of residual materials left in the tank from prior uses. The required agitation is preferably accomplished by an auger 40 which is mounted adjacent the bottom of the materials tank so as to extend longitudinally thereof, and the auger has the usual shaft 41 which is rotatably journaled such as in suitable bearings 42 (one shown). One end of the auger shaft 41 extends through the front end of the materials tank for connection to a drive motor 44 as will hereinafter be described.
As is known, comparatively large quantities of molten asphalt will cool at a relatively slow rate when it is contained in a tank of the above described character. However, in some instances, such as upon the occurrence of unexpectedly long delays between asphalt dispensing operations, and the like, it may become necessary to add heat to the molten asphalt in the tank 36 to maintain the proper temperature at which such materials will flow efficiently. Therefore, a fuel tank 46 having the usual controls 47 is mounted on the rear of the vehicle 10 for supplying fuel, such as propane, to a burner 48 which extends into a suitable heating jacket 49 provided in the tank 36.
As seen best in FIG. 1, the engine 28, which is employed to drive a power supply means as will become apparent as this description progresses, is mounted on the right hand front corner of the frame 12 of the vehicle 10 and has a suitable select gear transmission 50 coupled to its power output end through a clutch (not shown) which is selectively engageable by means of a foot operated clutch pedal 52. The transmission 50 is connected through a suitable coupling device 53 for driving a positive displacement hydraulic pump 54 which receives hydraulic fluid through a supply line 55 from a hydraulic fluid reservoir tank 56. The hydraulic pump 54 delivers fluid under pressure through a line 58 to drive the hydraulic motor 44 which is mounted to operate the auger 40 as hereinbefore mentioned. A line 60 is connected between the hydraulic motor 44 and the reservoir tank 56 by which the hydraulic fluid is returned to the reservoir tank. The hydraulic pump 54 has a built-in manually adjustable bypass valve 62 by which more or less hydraulic fluid is directed into the line 63 which is connected directly to the fluid return line 60. In this manner, more or less hydraulic fluid under pressure can be directed to the hydraulic motor for variable speed driving of the auger 40, and thus, the bypass valve 62 acts as a speed control.
Due to the nature of the auger 40 and the asphalt materials which are agitated thereby, the transmission 50 is also employed as a speed control for the auger and this is accomplished by selectively employing the desired gear ratio in the transmission to drive the hydraulic pump 54 at various speeds.
This rather sophisticated speed control arrangement for driving of the auger 40 is needed due to the fact that the residual asphalt left in the materials tank 36 from prior vehicle usage will solidify in the vicinity of the auger 40 and this invariably will lock up the auger. Thus, when starting operation of the vehicle, the addition of molten asphalt will slowly remelt the solidified residual asphalt and auger operation is impossible until some remelting has occurred. When a sufficient amount of remelting has occurred, the auger can be broken free and once agitation begins, total remelting will occur rather rapidly due to fluid circulation. The above described speed control system allows driving power to be carefully applied to the auger to break it free without damaging any of the equipment.
The transmission 50 is provided with a power takeoff unit 64 through which rotary power from the engine 28 is coupled to drive another positive displacement hydraulic pump 66. The pump 66 receives hydraulic fluid from a second hydraulic reservoir tank 68 through a fluid supply line 70. The pump 66 is a double pump in that it supplies hydraulic fluid under pressure to a first fluid delivery line 72 and simultaneously to a second fluid delivery line 74.
The first fluid delivery line 72 is routed along the side and back of the vehicle 10 to a control valve 76 which is mounted adjacent the operator's seat 34. The control valve 76 is a three position manually operated 4-way spool valve of the well known type which when it is in the neutral position will direct the hydraulic fluid received from the delivery line 72 to a fluid return line 78 which is connected to return the fluid back to the reservoir tank 68. Thus, in the neutral position of the control valve 76 the fluid will simply circulate without accomplishing any task.
When the control valve 76 is moved from its neutral position to a first operating position, the hydraulic fluid under pressure is directed through a line 80 to drive a hydraulic motor 82 in one direction with the motor being connected to operate an asphalt delivery pump 84 which is mounted on the asphalt output port 38 of the materials tank 36. In this first operating position of the control valve 76, the asphalt delivery pump 84 is operated to extract the molten asphalt from the materials tank 36 and pump the asphalt through its output port into an elongated flexible delivery hose 86 for materials dispensing purposes. The hydraulic fluid is returned from the motor 82 through a line 88 and is directed by the control valve 76 into the fluid return line 78 which returns it to the reservoir tank 68.
A bypass valve 90 is mounted between the first fluid delivery line 72 and the fluid return line 78, and the bypass valve 90 is a manually adjustable mechanism which allows more or less fluid to bypass the control valve 76. This allows variable speed operation of the hydraulic motor 82 and thus controls the flow rate of the molten asphalt through the asphalt delivery pump 84.
When the control valve 76 is moved to its second operating position, the incoming hydraulic fluid under pressure is directed through the hydraulic motor 82 in a reverse direction, i.e., the fluid is supplied to the motor through line 88 and returns through line 80. In this second operating position of control valve 76, the hydraulic motor 84 will run in the opposite direction and in turn will operate the pump 84 in the opposite direction. This operating mode is used when the asphalt dispensing operations of the vehicle 10 are terminated, or interrupted for longer than a few minutes, in that when so operated, the molten asphalt will be drawn back from the hose 86 and the delivery pump 84 into the materials tank 36 to prevent cooling and subsequent solidification of the asphalt therein.
The second fluid delivery line 74, from the hydraulic pump 66 is directed along the opposite side of the vehicle 10 to another control valve 92 which is also located adjacent the operator's seat 34 at the lefft rear corner of the vehicle 10. The control valve 92, as was the case with the previously described valve 76, is a three position manually operable 4-way spool valve. In the neutral position of the control valve 92, the hydraulic fluid supplied through the delivery line 74 is directed by the valve into a fluid return line 94 which is connected so as to return the fluid back to the reservoir tank 68, and thus circulate the fluid without accomplishing any task.
In the first operating position of the control valve 92, the hydraulic fluid under pressure is directed from the delivery line 74 to a line 96 which extends from the control valve to a hydraulic motor 98 which is mounted to supply rotational power to the differential 18 of the vehicle 10 via the drive shaft 20. The hydraulic motor 98 will therefore operate to move the vehicle 10 in one direction, and the hydraulic fluid is routed back from the motor 98 through a line 100, through the control valve 92 and into the fluid return line 94.
When the control valve 92 is moved to its second operating position, hydraulic fluid flow from the control valve 92 to the hydraulic motor 98 is reversed. In other words, fluid is supplied to the motor 98 through the line 100 and is returned therefrom through the line 96. This will run the hydraulic motor in the reverse direction and thus cause the vehicle 10 to move in a second, or reverse, direction.
A bypass valve 102 is mounted between the fluid delivery line 74 and the fluid return line 94, and this valve is a manually adjustable device which, by allowing more or less hydraulic fluid to bypass the control valve 92, provides variable speed operation of the hydraulic motor 98 and thus variable speed driving of the vehicle 10.
As shown, both of the fluid lines 96 and 100 which couple the control valve 92 and the vehicle moving hydraulic motor 98 are directed through a dual pilot operated relief valve 104. The purpose for the relief valve 104 is to provide a controllable braking action of the vehicle, and its operation will be more easily understood by describing what would happen in the absence of the relief valve 104.
When the vehicle 10 is being driven, in either direction, movement of the control valve 92 from either of its operating positions to its neutral position will completely close the fluid communication between the hydraulic motor 98 and the control valve 92, and such closing would trap the fluid in the lines and in the motor and cause it to lock up. However, inertia of the moving vehicle 10 will apply a load on the motor attempting to move it against the counteracting force applied by the trapped and immovable hydraulic fluid. In the best case, the vehicle would be brought to an abrupt stop and in the worst case, overpressurization could destroy the equipment.
This braking action is made more controllable by the relief valve 104 which, when the control valve 92 is moved to its neutral position, will allow an adjustably predetermined pressure buildup to occur in the hydraulic motor 98 and the fluid lines 96 and 100, and this pressure buildup is used to brake the vehicle. Any pressure buildup beyond the predetermined value will cause the relief valve 104 to open an amount proportional to the overpressurization and allow circulation of the trapped fluid.
To insure complete understanding of the operation of the relief valve 104, the following operational description is presented. It should be understood that when the vehicle 10 is being driven in either direction, the relief valve 104 is inoperative in that it allows hydraulic fluid flow to and from the hydraulic motor 98 in the above described manner. The relief valve 104 is provided with a first adjustable relief portion 106 and a second adjustable relief portion 108. When the vehicle 10 is being operated in the forward direction and the control valve 92 is moved into its neutral position, vehicle inertia will attempt to operate the hydraulic motor 98 so that it moves the trapped fluid into line 96 and extracts it from the line 100. When the pressure exerted on the fluid in this manner exceeds the predetermined value, the first relief portion 106 opens to provide a fluid communication from the line 100 to the line 96 and thus allow a controlled circulation of the fluid to occur in that direction. When the vehicle 10 is being operated in the reverse direction and the control valve 92 is moved to the neutral position, vehicle inertia will attempt to circulate the fluid in the direction opposite to that described above. In other words, the motor will try to move the trapped fluid from line 96 to line 100. When the pressure builds up beyond the adjustably predetermined point, the second adjustable relief portion 108 will open to provide fluid communication from the line 98 to the line 100 to allow controlled circulation to occur in this opposite direction.
From the above detailed description, it will be seen that the vehicle 10 of the present invention is ideally suited for its intended purpose in that the vehicle is configured to economically accomplish all of the functions and operations needed in the handling and dispensing of molten asphalt. Additionally, by physically locating the operator at the rear corner of the vehicle and by the adjacent placement of the controls, the operator can readily oversee the vehicle's operation and can control all of the functions which need manipulation during asphalt dispensing operations.
While the principles of the invention have now been made clear in an illustrated embodiment, there will be immediately obvious to those skilled in the art, many modifications of structure, arrangements, proportions, the elements, materials, and components used in the practice of the invention, and otherwise, which are particularly adapted for specific environments and operation requirements without departing from those principles.
For example, the electrically operated linear activator 24 by which the vehicle 10 is steered need not be an electric device, in that a hydraulic ram (not shown) would serve the same purpose. Further, the operator's seat 34 could be mounted on a swivel device to facilitate driving operation of the vehicle in either direction during its asphalt dispensing operations.
The appended claims are therefore intended to cover and embrace any such modifications within the limits only of the true spirit and scope of the invention. | A specialized vehicle for movement along a path parallel to a plurality of containers for dispensing molten asphalt from the vehicle into the containers. The vehicle is configured to physically locate the operator and the controls at the rear corner of the vehicle so that the operator can readily oversee and control movement of the vehicle and the asphalt dispensing operations. | 4 |
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims the priority benefit of Korean Patent Application No. 10-2015-0012700, filed on Jan. 27, 2015, in the Korean Intellectual Property Office, the disclosure of which is incorporated herein by reference.
BACKGROUND
[0002] 1. Field of the Invention
[0003] The present invention relates to a constrained application protocol (CoAP) communication method and a system for performing the CoAP communication method.
[0004] 2. Description of the Related Art
[0005] A constrained application protocol (CoAP) is a representational state transfer (REST) based protocol which is associated with a method of asynchronously transmitting, to a node, an event received and transmitted among resource-constrained machine-to-machine (M2M) nodes in an upper application layer including a transport layer including a user datagram protocol (UDP).
[0006] M2M technology provides a resource-oriented group communication method. An M2M application server, an M2M platform, an M2M terminal, an M2M gateway, and all data objects and local applications which are run on the M2M terminal and the M2M gateway are considered REST resources and identified by a uniform resource identifier (URI).
SUMMARY
[0007] An aspect of the present invention provides technology for allowing individual resources to be separately accessed without a need for a node including a plurality of integrated sub-unit resources to have separate Internet Protocol (IP) addresses for the individual resources, but to request only a single IP address and use the IP address and a unit identifier (ID) pair.
[0008] Another aspect of the present invention also provides a single constrained application protocol (CoAP) message including a unit ID to be used for controlling sub-devices.
[0009] Still another aspect of the present invention also provides technology for reducing a traffic flow among clients and terminals and saving energy in constrained devices by using a composite message for a unit ID.
[0010] According to an aspect of the present invention, there is provided a CoAP communication method including receiving a POST message for a registration request, verifying whether the registration request is valid in response to the POST message, and extracting a unit ID of at least one resource associated with a node from a message payload of the POST message and returning a response message.
[0011] The returning of the response message may include generating a resource location of the at least one resource, and returning a uniform resource identifier (URI) as the response message.
[0012] The verifying may include requesting an IP address and a port number of the node in response to a validity of the registration request being verified.
[0013] According to another aspect of the present invention, there is provided a CoAP communication method including receiving a GET request including a resource type, verifying whether the GET request is valid in response to the GET request, and obtaining IDs of registered resources corresponding to the resource type.
[0014] The CoAP communication method may further include returning a response message including a list of the IDs of the registered resources and a node IP address of a node including the registered resources.
[0015] According to still another aspect of the present invention, there is provided a CoAP communication method including selecting a unit ID of at least one resource from a list, generating the unit ID and a token pair, and transmitting a GET request to the resource using an URI.
[0016] The CoAP communication method may further include obtaining a node IP address and a port number of a node including the at least one resource.
[0017] The GET request may include the node IP address, the port number, and the unit ID.
[0018] The GET request may further include a unit size associated with a number of the at least one resource.
[0019] The CoAP communication method may further include receiving an acknowledgement (ACK) including data and a token transmitted from the resource, and verifying a source of the data by comparing the token of the ACK to the unit ID and the token pair.
[0020] The CoAP communication method may further include verifying a validity of the request and transmitting the ACK including the data and the token.
[0021] According to yet another aspect of the present invention, there is provided a CoAP node including a control module configured to select a unit ID of at least one resource from a list, and generate the unit ID and a token pair and generate a GET request, and a communication module configured to transmit the GET request.
[0022] The control module may obtain a node IP address and a port number of a node including the at least one resource.
[0023] The GET request may include the node IP address, the port number, and the unit ID.
[0024] The GET request may further include a unit size associated with a number of the at least one resource.
[0025] The control module may receive an ACK including data and a token transmitted from the resource, and verify a source of the data by comparing the token of the ACK to the unit ID and the token pair.
[0026] According to further another aspect of the present invention, there is provided a communication system including a node configured to transmit a POST message for a registration request, and a resource directory configured to verify whether the registration request is valid in response to the POST message, extract a unit ID of at least one resource associated with the node from a message payload of the POST message, and register the node and the at least one resource.
[0027] The resource directory may generate a resource location of the at least one resource, and return an URI as a response message.
[0028] The resource directory may request a node IP address and a port number of the node in response to a validity of the registration request being verified.
[0029] According to still another aspect of the present invention, there is provided a communication system including a client configured to transmit a GET request including a resource type, and a resource directory configured to verify whether the GET request is valid in response to the GET request, and obtain IDs of registered resources corresponding to the resource type.
[0030] The resource directory may return a response message including a list of the IDs of the registered resources and a node IP address of a node including the registered resources.
[0031] According to still another aspect of the present invention, there is provided a CoAP message header including a field including version information, type information, and length information of a CoAP message, and an option section including a unit ID field representing at least one resource associated with a node.
[0032] The option section may further include a unit size field representing a number of the at least one resource.
[0033] The unit ID field may repeat by the number of the at least one resource of the unit size field.
BRIEF DESCRIPTION OF THE DRAWINGS
[0034] These and/or other aspects, features, and advantages of the invention will become apparent and more readily appreciated from the following description of exemplary embodiments, taken in conjunction with the accompanying drawings of which:
[0035] FIG. 1 is a diagram illustrating an example of a communication system according to an embodiment of the present invention;
[0036] FIG. 2 is a diagram illustrating an example of usage of a multi-identifier (ID) node-based constrained application protocol (CoAP) resource directory according to an embodiment of the present invention;
[0037] FIG. 3 is a diagram illustrating an example of an operation of identifying and controlling resources of a composite node using a unit ID according to an embodiment of the present invention;
[0038] FIG. 4 is a data flow illustrating an example of message exchange between the CoAP client and the composite node of FIG. 3 ;
[0039] FIG. 5 is a diagram illustrating an example of an Internet Protocol (IP) and ID mapping based on a plurality of unit IDs according to an embodiment of the present invention;
[0040] FIG. 6 is a diagram illustrating an example of a configuration of the client of FIG. 1 ;
[0041] FIG. 7 is a diagram illustrating an example of a format of a CoAP message header according to an embodiment of the present invention;
[0042] FIG. 8 is a diagram illustrating an example of registering a resource of a node in a resource directory according to an embodiment of the present invention;
[0043] FIG. 9 is a diagram illustrating an example of a lookup process of a resource directory to be performed on an endpoint unit resource integrated into a single node, for example, a single IP address, according to an embodiment of the present invention;
[0044] FIG. 10 is a diagram illustrating an example of interaction between a client and a resource, for example, a CoAP server, according to an embodiment of the present invention; and
[0045] FIG. 11 is a diagram illustrating another example of interaction between a client and a resource, for example, a CoAP server, according to an embodiment of the present invention.
DETAILED DESCRIPTION
[0046] Hereinafter, some example embodiments will be described in detail with reference to the accompanying drawings. Regarding the reference numerals assigned to the elements in the drawings, it should be noted that the same elements will be designated by the same reference numerals, wherever possible, even though they are shown in different drawings. Also, in the description of embodiments, detailed description of well-known related structures or functions will be omitted when it is deemed that such description will cause ambiguous interpretation of the present disclosure.
[0047] It should be understood, however, that there is no intent to limit this disclosure to the particular example embodiments disclosed. On the contrary, example embodiments are to cover all modifications, equivalents, and alternatives falling within the scope of the example embodiments. Like numbers refer to like elements throughout the description of the figures.
[0048] In addition, terms such as first, second, A, B, (a), (b), and the like may be used herein to describe components. Each of these terminologies is not used to define an essence, order or sequence of a corresponding component but used merely to distinguish the corresponding component from other component(s). It should be noted that if it is described in the specification that one component is “connected”, “coupled”, or “joined” to another component, a third component may be “connected”, “coupled”, and “joined” between the first and second components, although the first component may be directly connected, coupled or joined to the second component.
[0049] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting. As used herein, the singular forms “a,” “an,” and “the,” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprises,” “comprising,” “includes,” and/or “including,” when used herein, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof.
[0050] It should also be noted that in some alternative implementations, the functions/acts noted may occur out of the order noted in the figures. For example, two figures shown in succession may in fact be executed substantially concurrently or may sometimes be executed in the reverse order, depending upon the functionality/acts involved.
[0051] Various example embodiments will now be described more fully with reference to the accompanying drawings in which some example embodiments are shown. In the drawings, the thicknesses of layers and regions are exaggerated for clarity.
[0052] A term, “module,” described herein may refer to hardware that may perform a function and an operation to be described hereinafter according to each name of a module. Alternatively, the term “module” may refer to a computer program code that may execute a function and an operation, or an electronic recording medium, for example, a processor, including the computer program code that may execute a function and an operation.
[0053] Thus, the term “module” may refer to hardware to implement technical features of the present invention and/or a functional and/or structural combination of software to execute the hardware. Each module may be referred to as a device.
[0054] FIG. 1 is a diagram illustrating an example of a communication system 10 according to an embodiment of the present invention.
[0055] Referring to FIG. 1 , the communication system 10 includes a client 100 , a resource directory 200 , and a plurality of nodes, for example, a sensor node 310 , an actuator node 320 , and a composite node 330 .
[0056] The communication systems 10 may be a system to which a constrained application protocol (CoAP) is applied. The CoAP may be a protocol intended towards devices constrained in terms of memory, processing, and power, for example, small-sized low-power sensors, switches, and valves. The CoAP may allow such devices to communicate among one another through the Internet.
[0057] The client 100 may also be referred to as a CoAP client or a CoAP node.
[0058] The nodes may include, for example, the sensor node 310 , the actuator node 320 , and the composite node 330 .
[0059] The sensor node 310 and the actuator node 320 may include a single resource, for example, a sensor and an actuator, respectively.
[0060] The composite node 330 may include a plurality of integrated resources, for example, a plurality of sensors and a plurality of actuators, or sensors and actuators.
[0061] Each node, for example, the sensor node 310 , the actuator node 320 , and the composite node 330 , may have a node identifier (ID).
[0062] Devices of each node may be separately identified through a unit ID. For example, a unit ID for a resource may be unique among all integrated resources in a single node, and an identical unit ID may represent integrated resources in another node.
[0063] The integrated resources in the single node may be separately identified by a node ID and a unit ID. For example, integrated resources in the composite node 330 may be separately identified by a node ID and a unit ID.
[0064] Each node, for example, the sensor node 310 , the actuator node 320 , and the composite node 330 , may have a single Internet Protocol (IP) address, and communicate with the client 100 and/or another module in the communication system 100 , for example, the resource directory 200 .
[0065] The unit ID used to identify individual integrated resources may be included in a unit ID option in a CoAP message.
[0066] The unit ID option in the CoAP message may enable usage of the composite node 330 including the sensors and actuators while having a single IP address for communication.
[0067] The integrated resources may individually or collectively communicate using the CoAP message including an additional option of a unit size (UnitSize) and a unit ID (UnitID), for example, the unit ID option, and be controlled using the CoAP message.
[0068] The UnitSize may be a numerical value indicating a number of sub-resources in the composite node 330 , and the UnitID may have a string ID for a sub-resource for which the message is intended.
[0069] Such options may enable the CoAP to communicate and control a plurality of resources by using a single composite message, for example, UnitID=“*”, and efficiently utilize IP addresses, for example, one IP multiple IDs, reduce communication traffic, and hence conserve power among such CoAP resources.
[0070] Each node, for example, the sensor node 310 , the actuator node 320 , and the composite node 330 , may register such resources in the resource directory 200 .
[0071] The resource directory 200 may define a set of functions, for example, discovery, registration, lookup, and the like.
[0072] When each node, for example, the sensor node 310 , the actuator node 320 , and the composite node 330 , registers all integrated resources of each node in the resource directory 200 , the client 100 may look up a single resource or a plurality of resources, and directly interact with such resources.
[0073] The resource directory 200 may enable automated discovery and lookup of resources, and a plurality of unit IDs may provide efficient utilization of a single IP for interaction with the resources.
[0074] FIG. 2 is a diagram illustrating an example of usage of a multi-ID node-based CoAP resource directory according to an embodiment of the present invention.
[0075] Referring to FIGS. 1 and 2 , the communication system 10 further includes a CoAP server 250 .
[0076] The CoAP server 250 may operate as the CoAP client 100 , and also operate as a reverse actor when such entities, the CoAP client 100 and the CoAP server 250 , have resources to share and request a certain resource from each other.
[0077] The discovery in the resource directory 200 may indicate a discovery of a location of a register function set in the resource directory 200 used to register a resource that the CoAP server 250 desires to share.
[0078] When a complete path is obtained for the register function set in the resource directory 200 , the CoAP server 250 may register or publish the resource in or to the resource directory 200 .
[0079] The CoAP client 100 may request the resource directory 200 to look up for the registered resource. The resource directory 200 may return an access path for the registered resource in response to the request made by the CoAP client 100 .
[0080] The returned resource may include a simple or composite resource, and the CoAP client 100 may communicate with such a resource.
[0081] A composite interaction with resources may be based on a unit ID, and the CoAP client 100 may interact with individual sub-devices or collectively interact with all the sub-devices of the composite node 330 .
[0082] FIG. 3 is a diagram illustrating an example of an operation of identifying and controlling resources of a composite node using a unit ID according to an embodiment of the present invention. FIG. 4 is a data flow illustrating an example of message exchange between the CoAP client 100 and the composite node 330 of FIG. 3 .
[0083] For ease of description, in the examples of FIGS. 3 and 4 , the composite node 330 is assumed to include a light sensor 330 - 1 and two switches, for example, a switch 330 - 3 and a switch 330 - 5 .
[0084] Referring to FIGS. 1 through 4 , the composite node 330 may be accessed via a single IP address assigned to the composite node 330 . Sub-resources, for example, the light sensor 330 - 1 and the switches 330 - 3 and 330 - 5 , of the composite node 330 may be accessed with unit IDs.
[0085] The composite node 330 as a CoAP endpoint may register, in the resource directory 200 , a resource in a form of a sub-unit. Thus, the resource directory 200 may have a single IP address for the composite node 330 and a unit ID for each sub-unit of the composite node 330 .
[0086] The CoAP client 100 may perform lookup on the resource directory 200 and obtain required resource information.
[0087] For ease of description, the CoAP client 100 is assumed to interact with the composite node 330 , and information regarding all the sub-units, for example, the light sensor 330 - 1 and the two switches 330 - 3 and 330 - 5 , is assumed to be provided to the CoAP client 100 by the resource directory 200 .
[0088] The CoAP client 100 may use the information regarding all the sub-units of the composite node 330 , for example, a unit size (UnitSize) and a unit ID (UnitID), to generate a request message, for example, a CoAP message, to interact with a single sub-unit or a plurality of sub-units of the composite node 330 .
[0089] For example, the CoAP client 100 may transmit a CoAP message, for example, with “UnitSize=1 and UnitID=LightSensor001,” to request data from the light sensor 330 - 1 . The composite node 330 may return a response message, for example, an acknowledge (ACK) message, including a UnitID parameter and sensor reading as a message payload.
[0090] In addition, the CoAP client 100 may transmit, as a single message, a CoAP message including options of “UnitSize=2 and UnitID=Light001, UnitID=Light002” to turn on or off light.
[0091] Using a composite message for a unit ID may reduce a traffic flow between the CoAP client 100 and endpoints, for example, the CoAP server 250 , and save energy in constrained devices.
[0092] FIG. 5 is a diagram illustrating an example of IP and ID mapping based on a plurality of unit IDs according to an embodiment of the present invention.
[0093] Referring to FIG. 5 , a network IP address and a local IP address may be used to access a network of a node and a physical node, respectively. In CoAP, a node ID may be used to ensure consistency of communication when a change in an IP address occurs at the client 100 or the server 250 during a communication session. Thus, a pair of the node IP address and the node ID may be used to communicate with a single resource.
[0094] The single node, for example, the composite node 330 , may include a plurality of integrated resources, and each resource may be represented by a plurality of sub-IDs.
[0095] A sub-ID for an integrated resource may be referred to as a unit ID, and a single node may have at least one unit ID.
[0096] Thus, use of a single IP address for communication with a plurality of resources or units may be enabled, and each resource may be treated as a separate entity having an own unique address without having a separate IP address.
[0097] Accordingly, the communication system 10 may represent a greater number of devices through effective utilization of an IP address space by combining the node IP and the unit ID as a pair.
[0098] FIG. 6 is a diagram illustrating the client 100 of FIG. 1 . Referring to FIGS. 1 through 6 , a CoAP node, for example, the client 100 , includes a control module 110 and a communication module 130 .
[0099] The control module 110 generates a request message, for example, a CoAP message, to interact with a sub-unit of each node, for example, the sensor node 310 , the actuator node 320 , and the composite node 330 .
[0100] For example, the control module 110 may generate the CoAP message to interact with a single sub-unit or a plurality of sub-units of the composite node 330 using information regarding all the sub-units, for example, the light sensor 330 - 1 and the two switches 330 - 3 and 330 - 5 , of the composite node 330 . The information regarding all the sub-units may be, for example, a unit size (UnitSize) and a unit ID (UnitID). For example, the control module 110 may generate a CoAP message of “UnitSize=1 and UnitID=LightSensor001” to request data from the light sensor 330 - 1 .
[0101] For another example, the control module 110 may generate a CoAP message including options of “UnitSize=2, and UnitID=Light001, UnitID=Light002” as a single message to turn on or off light.
[0102] The communication module 130 transmits the request message, for example, the CoAP message, generated by the control module 110 to a node, for example, the sensor node 310 , the actuator node 320 , and the composite node 330 .
[0103] FIG. 7 is a diagram illustrating an example of a format of a CoAP message header according to an embodiment of the present invention.
[0104] Referring to FIG. 7 , a header of a CoAP message includes a field, for example, a version (Ver) field, a type (T) field, and a token length field. The header also includes an option section.
[0105] In the option section, a unit size (UnitSize) field may specify a number of sub-units to be integrated into a single composite node, and a unit ID (UnitID) option may be present to hold a string ID for a unit ID representing a sub-unit in a composite node.
[0106] A UnitID field may be repeated multiple times depending on a numerical value of a UnitSize parameter, and represent a single spring ID for a sub-unit relating to a composite node each time.
[0107] FIG. 8 is a diagram illustrating an example of registering a resource of a node in a resource directory according to an embodiment of the present invention.
[0108] Referring to FIG. 8 , in order to register a node and resources integrated in the node in the resource directory, the node may transmit, to the resource directory, a CoAP POST message using a register function set of the resource directory for a registration request. A message payload may include a list of all unit IDs associated with the node.
[0109] The resource directory may receive the CoAP POST message, and verify whether the registration request is valid. For example, when the resource directory receives a valid registration request from the node, a source IP address and a port number may be obtained from a CoAP request parameter or a message source address portion, for example, a default.
[0110] The resource directory may extract the unit IDs from the message payload, generate a resource location of all the resources, and return a response message to the node.
[0111] When such a registration process is successful, a location uniform resource identifier (URI) may be returned to the node requesting the registration, and the registration of the integrated resources may be canceled by updating the registration or removing a location entry.
[0112] Conversely, when the registration process is unsuccessful, an error message may be returned to mention a cause of such a failure.
[0113] FIG. 9 is a diagram illustrating an example of a lookup process of a resource directory to be performed on an endpoint unit resource integrated into a single node, for example, a single IP address, according to an embodiment of the present invention.
[0114] In the example of FIG. 9 , a client is assumed to make a request for a certain type, for example, a temperature, of a resource registered in the resource directory (RD).
[0115] Referring to FIG. 9 , the client transmits, to the resource directory, a GET request, for example, a GET request message, including a resource type that the client desires to look up in the resource directory.
[0116] The resource directory receives the GET request, for example, the GET request message, verifies whether the GET request message is a valid CoAP request, and obtains IDs of all registered resources including a numerical value corresponding to the resource type, for example, the temperature.
[0117] The resource directory generates a response message including a list of the IDs of the resources and node IP addresses.
[0118] The client selects a resource from the list, and directly communicates with the selected resource using a CoAP.
[0119] When such a lookup process is not successful, an error message may be returned to mention a cause of such a failure.
[0120] FIG. 10 is a diagram illustrating an example of interaction between a client and a resource, for example, a CoAP server, according to an embodiment of the present invention.
[0121] As described with reference to FIG. 9 , the client may look up for a resource of a certain resource type in the resource directory, and obtain a list of IDs, for example, node IDs and unit IDs, of all resources registered in the resource directory.
[0122] FIG. 10 illustrates a process of selecting a resource from the list and directly communicating with the selected resource by the client.
[0123] Referring to FIG. 10 , when the client interacts with a resource and the resource is a composite node, the client obtains a complete URI, for example, a node IP address, a port number, and a unit ID.
[0124] For a simple resource, for example, a sensor and an actuator, a node ID may be used along with an IP address to allow interaction between a CoAP client and a server to be performed.
[0125] For a composite resource, for example a plurality of integrated resources, the client may generate a unit ID and a token pair and transmit a GET request to a resource integrated into a node using the complete URI. A token used herein may indicate a CoAP token to be transmitted along with a general GET request.
[0126] The node, for example, the CoAP server, verifies a validity of the request, and responds to the client with an ACK including a token and data from the integrated resource. The client verifies a source of the data by comparing the token of the ACK to the stored unit ID and the token pair.
[0127] FIG. 11 is a diagram illustrating another example of interaction between a client and a resource, for example, a CoAP server, according to an embodiment of the present invention.
[0128] For ease of description, in the example of FIG. 11 , both unit IDs are assumed to belong to a single node. However, a unit ID may belong to at least one CoAP node.
[0129] As described with reference to FIG. 9 , the client may look up for a resource of a certain resource type in the resource directory, and obtain a list of IDs, for example, node IDs and unit IDs, of all resources registered in the resource directory.
[0130] FIG. 11 illustrates a process of selecting a resource from a list provided by the resource directory for the client to interact with a plurality of unit resources.
[0131] Referring to FIG. 11 , the client selects a complete URI, for example, a node IP address, a port number, and a unit ID, for communication, and generates and stores the unit ID and a token pair. A token used herein may indicate a CoAP token to be transmitted along with a general GET request.
[0132] The client transmits a GET request to resources integrated into a single or at least one node using the complete URI, for example, a node IP address, a port number, a node ID, and a unit ID.
[0133] In addition, the GET request including a plurality of unit IDs may include a unit size parameter indicating a number of the integrated resources.
[0134] The node, for example, the CoAP server verifies a validity of the request, and responds to the client with an ACK including a token and data from the integrated resources.
[0135] The client verifies a source of the data by comparing the token of the ACK to the stored unit ID and the token pair.
[0136] The various modules, elements, and methods described above may be implemented using one or more hardware components, one or more software components, or a combination of one or more hardware components and one or more software components.
[0137] A hardware component may be, for example, a physical device that physically performs one or more operations, but is not limited thereto. Examples of hardware components include resistors, capacitors, inductors, power supplies, frequency generators, operational amplifiers, power amplifiers, low-pass filters, high-pass filters, band-pass filters, analog-to-digital converters, digital-to-analog converters, and processing devices.
[0138] A software component may be implemented, for example, by a processing device controlled by software or instructions to perform one or more operations, but is not limited thereto. A computer, controller, or other control device may cause the processing device to run the software or execute the instructions. One software component may be implemented by one processing device, or two or more software components may be implemented by one processing device, or one software component may be implemented by two or more processing devices, or two or more software components may be implemented by two or more processing devices.
[0139] A processing device may be implemented using one or more general-purpose or special-purpose computers, such as, for example, a processor, a controller and an arithmetic logic unit, a digital signal processor, a microcomputer, a field-programmable array, a programmable logic unit, a microprocessor, or any other device capable of running software or executing instructions. The processing device may run an operating system (OS), and may run one or more software applications that operate under the OS. The processing device may access, store, manipulate, process, and create data when running the software or executing the instructions. For simplicity, the singular term “processing device” may be used in the description, but one of ordinary skill in the art will appreciate that a processing device may include multiple processing elements and multiple types of processing elements. For example, a processing device may include one or more processors, or one or more processors and one or more controllers. In addition, different processing configurations are possible, such as parallel processors or multi-core processors.
[0140] A processing device configured to implement a software component to perform an operation A may include a processor programmed to run software or execute instructions to control the processor to perform operation A. In addition, a processing device configured to implement a software component to perform an operation A, an operation B, and an operation C may have various configurations, such as, for example, a processor configured to implement a software component to perform operations A, B, and C; a first processor configured to implement a software component to perform operation A, and a second processor configured to implement a software component to perform operations B and C; a first processor configured to implement a software component to perform operations A and B, and a second processor configured to implement a software component to perform operation C; a first processor configured to implement a software component to perform operation A, a second processor configured to implement a software component to perform operation B, and a third processor configured to implement a software component to perform operation C; a first processor configured to implement a software component to perform operations A, B, and C, and a second processor configured to implement a software component to perform operations A, B, and C, or any other configuration of one or more processors each implementing one or more of operations A, B, and C. Although these examples refer to three operations A, B, C, the number of operations that may implemented is not limited to three, but may be any number of operations required to achieve a desired result or perform a desired task.
[0141] Functional programs, codes, and code segments for implementing the examples disclosed herein can be easily constructed by a programmer skilled in the art to which the examples pertain based on the drawings and their corresponding descriptions as provided herein.
[0142] Software or instructions for controlling a processing device to implement a software component may include a computer program, a piece of code, an instruction, or some combination thereof, for independently or collectively instructing or configuring the processing device to perform one or more desired operations. The software or instructions may include machine code that may be directly executed by the processing device, such as machine code produced by a compiler, and/or higher-level code that may be executed by the processing device using an interpreter. The software or instructions and any associated data, data files, and data structures may be embodied permanently or temporarily in any type of machine, component, physical or virtual equipment, computer storage medium or device, or a propagated signal wave capable of providing instructions or data to or being interpreted by the processing device. The software or instructions and any associated data, data files, and data structures also may be distributed over network-coupled computer systems so that the software or instructions and any associated data, data files, and data structures are stored and executed in a distributed fashion.
[0143] While this disclosure includes specific examples, it will be apparent to one of ordinary skill in the art that various changes in form and details may be made in these examples without departing from the spirit and scope of the claims and their equivalents. The examples described herein are to be considered in a descriptive sense only, and not for purposes of limitation. Descriptions of features or aspects in each example are to be considered as being applicable to similar features or aspects in other examples. Suitable results may be achieved if the described techniques are performed in a different order, and/or if components in a described system, architecture, device, or circuit are combined in a different manner and/or replaced or supplemented by other components or their equivalents. Therefore, the scope of the disclosure is defined not by the detailed description, but by the claims and their equivalents, and all variations within the scope of the claims and their equivalents are to be construed as being included in the disclosure. | Provided is a constrained application protocol (CoAP) communication method and a system for performing the method, wherein the method includes receiving a POST message for a registration request, verifying whether the registration request is valid in response to the POST message, extracting a unit identifier (ID) of at least one resource associated with a node from a message payload of the POST message, and returning a response message. | 7 |
FIELD OF THE INVENTION
[0001] The field of the invention is removable plugs and more particularly plugs filled with a solid material that is contained in a porous member that has its shape changed to set the plug and the plug structure subsequently altered for release of the plug.
BACKGROUND OF THE INVENTION
[0002] Zones in a wellbore have been isolated from each other with sand plugs. Typically, a porous substrate is supported in the wellbore and sand is pumped onto the substrate. Pressure is applied and the sand is dewatered. If a long enough sand column is created, the pressure applied from pumped fluid above forces the sand particles together in such a manner as to create a barrier to isolate zones in a wellbore from each other. When the barrier is no longer needed a jetting tool at the end of coiled tubing or the like is run into position above the plug. The jetting action and the circulation starts to work on the compacted sand pile and eventually allows the particles to come off the cohesive plug and get lifted from the well with the circulating fluid that exits the jetting nozzles. Some examples of this technique are U.S. Pat. No. 5,623,993 and 5,417,285. Other efforts in horizontal wells involve recipes of a variety of granular components that have predetermined properties such as specific gravity below 1.25 to create the plug using deposition techniques. One example of this is U.S. Pat. No. 7,690,427.
[0003] Other designs place swelling material in porous enclosures and allow the swelling action to create relative movement that allows a packer to go from a run in to a set position as overlapping petals of swelling material in enclosures rotate relatively to reach a sealing configuration in a borehole. This technique is illustrated in U.S. Pat. No. 7,422,071.
[0004] What is needed and provided by the present invention is a plug that can be set with a setting tool that creates relative movement and features a solid granular material in a porous enclosure where the setting action alters the shape of the enclosure to attain the set position. This can be done by bringing one end closer to another end and preferably through a passage in an annularly shaped sheath. Alternatively a swage can be brought through a passage in an annularly shaped sheath to enlarge the passage and in so doing set up the fill material in the sheath to push against the surrounding wellbore while a valve such as a flapper closes the passage to pressure from above. The porous enclosure can then be undermined in a variety of ways to allow the granular material to escape where it can be removed with fluid circulation. In some variations, a mandrel allows flow therethrough until an object is landed on a seat for zonal isolation. In other instances the mandrel can be undermined as a way of letting the granular material escape. The retaining porous material can be dissolved or in other ways removed so that it will not interfere with the working of other tools in the borehole. For fracturing plug purposes, perfect sealing is not required as long as sufficient flow past the plug is sufficiently slowed so that the acting pressure can deliver the requisite flow into the fractures to further open them, in the known manner. The use of a mandrel can also be optional and the plug structure can comprise a granular material in a porous enclosure that folds on itself to set. An optional lock feature or a valve to prevent reverse flow in the setting location when relative movement occurs can also be incorporated. These and other features can be incorporated into the design as will be more readily apparent to those skilled in the art from review of the details of the description of the preferred embodiment and the associated drawings, while understanding that the full scope of the invention is to be determined from the appended claims.
SUMMARY OF THE INVENTION
[0005] The removable plug features a solid material that is housed in a porous container that has its shape changed to transition from the run in shape to the set shape. A running string and setting tool that creates relative movement deliver the plug and pull on its lower end while holding the top stationary against a backing plate. The container is pulled into itself as the radial dimension grows for the set. There can be a mandrel that remains in position and can lock to the backing plate or alternatively there can be no mandrel or a removable mandrel. In an alternative embodiment a setting tool pulls a swage through a passage in an annularly shaped sheath to set up the granular material in the sheath to seal against the borehole wall while the enlarged passage is closed off with a valve such as a flapper after the swage exits the passage. The porous container can be removed in a variety of ways to let the solid material escape to be removed with fluid circulating in the wellbore. Alternatively the mandrel can be undermined to let the solid material escape for recovery.
BRIEF DESCRIPTION OF THE DRAWINGS
[0006] FIG. 1 is a view for run in of one embodiment of the removable plug;
[0007] FIG. 2 is the view if FIG. 1 in the setting process as the mandrel is raised internally of the plug;
[0008] FIG. 3 is the view of FIG. 2 with the plug in the set position and the mandrel removed;
[0009] FIG. 4 is an alternative embodiment of the plug shown in the run in position;
[0010] FIG. 5 is the view of FIG. 4 during the setting process;
[0011] FIG. 6 is the view of FIG. 5 with the plug in the set position and the mandrel left in place;
[0012] FIG. 7 is an alternative embodiment schematically illustrated in the run in position;
[0013] FIG. 8 is the view of FIG. 7 showing the swage advanced through the passage in the sheath and the passage closed with a flapper to differential pressure from above.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0014] Referring to FIG. 1 the wellbore 10 can be cased or open hole. An elongated porous sheath 12 can be made of a variety of materials that have the requisite strength to contain the loose solid material 14 contained inside as the shape of the sheath 12 is changed. The sheath 12 can be a mesh material using high strength fibers such as Kevlar® or it can also be made of textile materials that are more readily undermined when it is time to release the plug while at the same time minimizing the presence of large pieces of the sheath 12 . One possible such sheath material would be nylon. Another is controlled electrolytic material that degrades under certain well conditions to release the fill material 24 when a plug release is needed. The sheath 12 has an initial annular shape with a mandrel 14 extending through the sheath 12 from a top 16 to a bottom 18 . The connection at 18 between the sheath 12 and the mandrel 14 is designed to release on application of a predetermined force. A running string or wireline or some other conveyance 20 has a setting tool S that creates relative movement between the backup 22 and the mandrel 14 . Such tools are well known in the art and one such tool is the E-4 Wireline Setting Tool sold by Baker Hughes Incorporated. The fill material 24 can be sand, coated proppant, controlled electrolytic material rubber chips or some other solid granular material that will be retained by the sheath 12 as the setting tool S it actuated as shown in FIG. 2 . For release the controlled electrolytic material can degrade with well conditions to allow the sheath 12 to go slack so that the plug can be removed. FIG. 2 illustrates the lower end 18 being brought up with the mandrel 14 so that the overall length is shortened as the diameter is increased and the reconfigured shape brings the sheath 12 with the fill material 24 now compressed so that fluid is displaced from its void spaces and those spaces close up. This results in the mass of the fill material 24 in the sheath 12 becoming more and more or completely impervious to through fluid flow. With the radial pressure exerted against the borehole 10 there is now in the FIG. 2 position some or total zonal isolation. As an option the set position can be FIG. 2 with the mandrel 14 remaining in the position shown and a ratchet locking system 26 that allows the mandrel 14 to be pulled up but will prevent reverse direction motion can be used. When doing so the setting tool S can have a breakaway connection 28 to allow its removal after the setting is complete. As a different option, the mandrel 14 can be pulled free of the lower end 18 of the sheath 12 without damage to the sheath 12 . The release from the sheath 12 can be based on movement of a predetermined distance or the application of a predetermined force. The mandrel 14 is shown in dashed lines in FIG. 3 after a release from the lower end 18 and after having been raised clear of the backup 22 which allows the flapper 30 that can be spring biased for example with a coiled spring around a pivot shaft akin to subsurface safety valves to the closed position shown in FIG. 3 . The closing of the flapper or other type of closure 30 prevents pressure above the set plug from pushing end 18 back to its original position and undermining the set position. As seen in FIG. 3 the space formerly occupied by the mandrel 14 is closed by the sheath changing shape so that radial sealing force can be exerted against the surrounding borehole 10 . It should be noted that particularly in fracturing application that complete sealing is not required. Rather sufficient isolation to allow the required volume at the required pressure to reach the perforations to initiate fractures, enlarge them and deliver proppant to keep them open for subsequent production works sufficiently well. As noted in the embodiment of FIGS. 1-3 the act of setting the plug gets the desired isolation. While a hollow mandrel 14 can be used to allow initial flow through such as during running in, removal of the mandrel puts the plug in functional operating position as a barrier.
[0015] There are alternatives available for plug removal from the FIG. 2 set position or the FIG. 3 set position. The mandrel can be made from a material that will degrade in the presence of well fluids or other fluids added to the well. The mandrel 14 can be made from a controlled electrolytic material. Controlled electrolytic materials have been described in US Publication 2011/0136707 and related applications filed the same day. These materials degrade to undermine the seal and can be attached to the sheath 12 in such a manner that the degradation will also cause a failure in the sheath 12 and release of the material 24 that can be removed with circulation or reverse circulation. Alternatively a jet tool can be lowered to reach the sheath and undermine it to allow the material 24 to escape. Another way is to undermine the sheath such as by chemical reaction or melting it so that the sheath remnants and the material 24 can be moved out to the surface with flowing fluids.
[0016] FIGS. 4-6 are an alternative embodiment that has a hollow mandrel 32 connected to lower end 34 of sheath 36 that has fill material 38 inside. Mandrel 32 is pulled through the backup 38 by a setting tool as previously described for the FIGS. 1-3 embodiments. The upper end 40 of the sheath 36 is held firm against the backup 38 as the lower end 34 is brought closer to the upper end 40 . The length of the sheath 36 is reduced as its diameter is increased. Eventually contact with the borehole 42 is made. Borehole 42 can be a tubular or it can be open hole. FIG. 5 shows the onset of the setting process with the lower end 34 coming closer to the upper end 42 that is held stationary by the setting tool S. As before the particulate material 44 is rearranged by the raising of the mandrel 32 as liquids are forced out of the spaces in the material 44 and through the sheath 36 that is preferably a permeable mesh. FIG. 6 shows the fully set position. The mandrel 32 can have a seat 46 on which an object 48 can be landed for sealing contact so that that the plug will function as a frac plug by isolating adjacent zones even if some seepage flow still occurs. The compaction of the material 44 due to raising the mandrel 32 while holding the backup 38 fixed, reforms loose granular material into a more cohesive whole making it impervious or nearly impervious to flow under differential pressure. FIG. 6 illustrates a ratchet locking device that allows the mandrel 32 to be raised when bringing end 34 closer to end 40 while preventing movement in the opposite direction to hold the set position of FIG. 6 against differential pressure from above. Of course, in this embodiment as in the previous embodiment differential pressure from below will merely urge further compression of the material 44 and potentially further bring location 34 closer to location 40 with the lock 50 holding the new position.
[0017] Those skilled in the art will appreciate that one or more plugs can be commonly mounted and actuated on a common mandrel. While textiles in mesh form are preferred for the sheath other flexible and porous materials are also envisioned while preference is given to materials that can be more easily undermined for the release of the set plug. Alternatively the mandrel can be undermined to remove the compressive stress from the plug in a set position and to optionally also undermine the sheath at the location of attachment to the mandrel. The sheath or mandrel can respond to well conditions that occur naturally for the release or well conditions can be altered deliberately for the release feature. Another way to release is to simply lower a jet tool and size the backup such that some of the jet streams can go around the backup and impact the sheath to cause openings to form in the sheath and thus to start the release process.
[0018] In essence, an annular sheath contains the solid material that will serve as the barrier and is turned inside out in the setting process that brings a lower end up through a central opening in the sheath shape and toward an upper end that is held fixed by the setting tool. The use of the sheath minimizes the amount of material needed to form a reliable barrier as compared to prior techniques of simply pumping sand onto a porous barrier. While one type of filler material can be used, blends of differing materials are also envisioned.
[0019] FIGS. 7 and 8 represent an alternative embodiment where the solid material 60 is inside a sheath 62 as before. A passage 64 goes through the sheath 62 to define the annular shape for the sheath. A swage 66 is shown at the lower end of the passage 64 and is connected to a setting tool 68 suspended by a string such as wireline, coiled tubing or other elongated conveyance. Support 72 is retained by the setting tool 68 while the swage 66 is drawn into the passage 64 . As a result the size of the passage 64 increases as the overall dimension of the sheath increases until contact is made with the borehole 74 which can be a tubular or an open hole at the setting location. The increase in dimension of the passage 64 and the contact of the sheath 62 to the borehole 74 compacts the material 60 pushing out fluid and packing the solid material into a cohesive whole that becomes impervious to fluid. The setting tool 68 moves the swage clear of the passage to allow a valve such as a flapper 76 to either fall to the closed position by its own weight or through the use of a biasing member acting on the flapper 76 or its pivot pin 78 . Optionally the force of the biasing can be retained by a latch that is released by the passing swage 66 . FIG. 8 shows the flapper 76 in the closed position so that differential pressure from above can be sufficiently retained to perform an operation above the plug in the FIG. set position. The plug need not be leak free and the operation above the plug can be fracturing.
[0020] As an alternative to the flapper 76 , a mandrel such as 80 that can be positioned with movement of the swage 66 or in the alternative can be expanded by the swage 66 if it is initially in position in the passage 64 can have a seat as described with the previous embodiment so that an object can be dropped on such seat to seal off the passage 64 in this alternative manner. Leaving the passage 64 open after setting the plug allows easy removal of an associated perforating gun that is initially delivered with the plug and the delivery by pumping of a replacement gun through the passage 64 that is still open because an object has yet to be dropped onto the seat in the mandrel. It should be noted that if the mandrel is initially in position in the passage 64 then the swage 66 would start expanding from a location past the seat to avoid damage to the seat and allow the seat to maintain its initial size.
[0021] The swage 66 can be fixed or variable and the swage direction can also be in the downhole direction as opposed to the uphole direction shown in FIGS. 7 and 8 . If swaging in the downhole direction, the swage 66 can either be dropped in the hole after expansion or simply passed back through the enlarged passage 64 that its original movement has just created.
[0022] While relative movement described in the embodiments of FIGS. 1-6 has been to bring ends such as 34 and 40 together, relative movement in the opposite direction is also contemplated to accomplish the setting. Additionally, when the setting occurs by bringing ends together the release can also be accomplished by forcing the ends apart while forcibly overcoming any latching device designed to hold the set position. For example a tool can find support against the plate 38 while pushing the mandrel 32 and overcoming the ratchet 50 .
[0023] Optionally a releasable mandrel 80 can be releasably attached to the swage 66 to be deposited in the expanded passage 64 after the swage 66 passes. The mandrel 80 can be solid or it can have a passage threrthrough that is later closed by the flapper 76 .
[0024] The above description is illustrative of the preferred embodiment and many modifications may be made by those skilled in the art without departing from the invention whose scope is to be determined from the literal and equivalent scope of the claims below: | The removable plug features a solid material that is housed in a porous container that has its shape changed to transition from the run in shape to the set shape. A running string and setting tool that creates relative movement deliver the plug and pull on its lower end while holding the top stationary against a backing plate. The container is pulled into itself as the radial dimension grows for the set. There can be a mandrel that remains in position and can lock to the backing plate or alternatively there can be no mandrel or a removable mandrel. The porous container can be removed in a variety of ways to let the solid material escape to be removed with fluid circulating in the wellbore. Alternatively the mandrel can be undermined to let the solid material escape for recovery. | 4 |
BACKGROUND OF THE INVENTION
Continuing concerns over pollution of ground water supplies has increased the need for the construction of residential and commercial waste water treatment facilities. The need for the treatment facilities is particularly acute in those areas which are growing rapidly or are experiencing shortfalls in water supply. In many areas of the country, localities are experiencing both a water shortage and rapid growth.
Conventional waste water treatment techniques employ a number of tanks or basins which are interconnected through pipes, pumps, and similar plumbing. These facilities not only are expensive to construct, but also occupy much land. Since each facility occupies a relatively large area of land, then expansion is made further more expensive and/or difficult in view of the need to acquire additional land. Also, the piping cost for the facilities can be quite high in view of the distance between the tanks.
A typical waste water treatment facility will have an optional surge tank or basin, for smoothing out fluctuations in waste water input, followed by a number of subsequent processing tanks. Many systems employ an aeration tank wherein oxygen is added to the waste water for causing carbon to be consumed. A settling tank typically follows the aeration tank in order to permit debris and solids to be separated from the aerated water. The sediment from the settling tank may thereafter be directed optionally to a sludge digester, or normally to the inlet of the aeration tank.
Those skilled in the art will appreciate that there is a need for a waste water treatment facility which is relatively inexpensive to construct, which occupies a relatively small amount of land, and which readily permits expansion as required. The disclosed invention is just such a waste water treatment facility.
OBJECTS AND SUMMARY OF THE INVENTION
The primary object of the disclosed invention is a waste water treatment facility which is inexpensive to construct, which occupies minimal land, and which readily permits expansion.
A compact waste treatment facility according to the invention includes an optional surge basin, an aeration basin, a settling basin, and a digester basin. The basins are interconnected in the order named for therewith providing a sequentially arranged waste treatment facility. Each of the basins is comprised of six integral walls which are substantially equiangularly disposed one to the other, so that each basin is hexagonally shaped in plan. Each basin has a wall common with the basin interconnected therewith. Means are operably associated with each of the basins for supplying fluid treated therein to the next interconnected basin, and means are operably associated with the aeration basin for causing fluid flow thereabout.
A waste water treatment facility according to the invention includes two or more sequentially oriented honeycomb-shaped cementitious basins, with each basin connected to at least one other basin by a joint wall. Means are operably associated with an end one of said basins for supplying waste water to be treated thereto, and means are operably associated with an oppositely disposed end one of said basins for removing treated waste water therefrom. Means are operably associated with each of the basins for causing waste water therein to be discharged to the sequentially next basin, and means are operably associated with an intermediate one of the basins for aerating waste water therein.
These and other objects and advantages of the invention will be readily apparent in view of the following description and drawings of the above described invention.
DESCRIPTION OF THE DRAWINGS
The above and other objects and advantages and novel features of the present invention will become apparent from the following detailed description of the preferred embodiment of the invention illustrated in the accompanying drawings, wherein:
FIG. 1 is a schematic view of a waste water treatment facility according to the invention with the dotted line showing illustrating potential expansion;
FIG. 2 is a schematic view of a prior art waste water treatment facility;
FIG. 3 is a top plan view of a waste water treatment facility according to the invention with portions shown in phantom;
FIG. 4 is a cross-sectional view taken along the line 4--4 of FIG. 3 and viewed in the direction of the arrows;
FIG. 5 is a cross-sectional view taken along the line 5--5 of FIG. 4 and viewed in the direction of arrows;
FIG. 6 is a top plan view, partially in section, of a detail of FIG. 3;
FIG. 7 is a top plan view with portions shown in phantom of yet a further detail of FIGS. 3; and,
FIG. 8 is a top plan view with portions shown in phantom of yet an additional detail of FIG. 3.
DETAILED DESCRIPTION OF THE INVENTION
Waste water treatment facility W, as best shown in FIG. 3, include an optional surge basin 10, an aeration basin 12, a settling basin 14, and a sludge digester basin 16. Each of the basins 10, 12, 14 and 16 is comprised of a cementitious material, such as concrete, and is of a honeycomb format in plan. I have found that the six (6) sided honeycomb format permits maximum utilization of available space while simultaneously permitting a significant reduction in piping and expansion costs.
FIG. 2 discloses a conventional waste water treatment facility comprising a plurality of aeration basins 18 interconnected by appropriate piping (not shown) to clarifiers 20 and digesters 22. FIG. 1 discloses a second embodiment of the facility of FIG. 3 as applied to a land area corresponding to the land area of FIG. 2. The facility of FIG. 1 includes a plurality of surge basins 24 operably interconnected each with at least two aeration basins 26 through appropriate pumps and pipes (not shown). The interconnection of each aeration basin 26 with two surge basins 24 maximizes flexibility in operation and maintenance, since water to be treated may be directed to either of two basins for aeration as required. Each aeration basin 26 is operably connected by a valved weir to at one or more settling basins 28, each of which is then connected to a digester 30 by pumps (not shown).
The phantom line showing in FIG. 1 illustrates the additional two, at least, treatment facilities which may be installed in the same land area as is occupied by the four facilities of FIG. 2. Not only is there an increase in land usage, but the hexagonal configuration of the basins 24, 26, 28 and 30, each of which shares a support wall in common with the interconnected basin, minimizes piping costs and facilitates expansion. The common wall design, allowing water storage on both sides, greatly reduces the amount of concrete required for a given facility since lateral support is provided. The facility of FIG. 1 permits a greater number of treatment plants per unit space, while the use of plural surge and settling basins for each aeration basin maximizes flexibility in a manner not before possible.
Each of the basins 10, 12, 14 and 16 of FIG. 3, as with the basins 24, 26, 28 and 30 of FIG. 1, is hexagonal in plan, although other configurations may be used. Each of the basins has six (6) side walls equiangularly disposed one to the other. The side walls of the basins 10, 14 and 16 are of a uniform length. This common length assures that each of the basins 10 14 and 16 is of substantially the same size and may therefore be constructed from the same forms, therefore minimizing construction costs.
The aeration basin 12 of FIG. 3 likewise is hexagonal in plan, with six walls equiangularly disposed relative one to the other. Unlike the basins 10, 14 and 16, the basin 12 has parallel side walls 32 and 34 which are of a length substantially in excess of the length of side walls 36, 38, 40 and 42. The side walls 32 and 34 are much longer than the other side walls in order to create an aeration basin 12 which has a residence period sufficient for satisfactory treatment of the incoming waste water. Those skilled in the art understand that some period of time is required for the aeration process to proceed to the desired completion, and the residence period is therefore a function of the quality of the incoming water, the amount of aeration, and the desired quality of the output water.
In order to facilitate aeration, I provide a plurality of floating aeration assemblies 44 and 46, which aerate the water while also driving it about the basin 12. Preferably, each of the aeration assemblies 44 and 46 is disposed on one side of a concrete divider 48 which has a length less than the length of the parallel side walls 32 and 34 and is interposed therebetween. The aeration assemblies 44 and 46 substantially span the distance between the divider 48 and the associated side walls 32 and 34, respectively. The aeration assemblies 44 and 46 cooperate with each other in facilitating flow about the basin. In addition, I provide flow guide baffles 50 and 52 within the basin 12 at opposite ends of the divider 48. The baffles 50 and 52 are likewise formed of concrete, and are U-shaped in plan. Each of the baffles 50 and 52 is spaced from an associated end of the divider 48, and also from the associated endwalls 36 and 38 or 40 and 42, respectively. Each of the baffles 50 and 52 has somewhat linear portions extending longitudinally along the divider 48, with the result that each end of the divider 48 is nestled within its associated baffle. The ends of the divider 48 are uniformly spaced from the linear portions of the baffles 50 and 52, so that substantially uniform flow is achievable in the bisected basin 12. The baffles 50 and 52 cooperate with the divider 48 in order to facilitate substantially complete flow of the water about the basin 12. The aeration basin may also be equal sided, like the digester, with one floating aerator in the center. In this instance the internal divider and baffle walls would not be required.
The floating aeration assemblies 44 and 46 permit the aeration basin to seave as a surge basin, since variations in volume will be accomodated by vertical displacement of the aeration assemblies 44 and 46. If a surge basin is used, then the floating assemblies 44 and 46 act to dampen flow from the surge basin and provide additional capacity for high flow periods. Thus, since the floating assemblies will have a high and a low position, the difference therebetween provides surge capacity.
A typical hexagon has rather sharp angles between adjacent walls, which sharp angles might be sufficient to cause flow perturbations. For this reason, I have smoothed and rounded-off the angle between adjacent walls, such as the walls 34 and 42, as a means for reducing flow inefficiencies. The rounded-off portion 54, is provided at the interconnection of the side walls of each of the basins 10, 12, 14 and 16 in order to cause the associated basin to more accurately resemble an oval or circle, as appropriate. The rounded-off portion 54 at the walls 34 and 42 is exemplary. The oval shape is more accommodating to flow, and thereby the rounded-off portions 54 permit greater flow efficiencies to be achieved than would be possible with the usual sharp angles.
The aeration assemblies 44 and 46 are identical, and the aeration assembly 44 is more particularly shown in FIGS. 4 and 5. The aeration assembly 44, as best shown in FIG. 4, includes aerators 56, 58 and 60 interconnected by planar member 62. Each of the aerators has side supports 64 and 66 disposed in parallel and sufficiently buoyant to maintain the aerator at a selected level relative to the surface 68 of the waste water 70. Extending between each of the parallel supports 64 and 66 is a paddlewheel-shaped drive 72 which is driven about axis 74 by a motor assembly 75 operably associated therewith. The drives 72 of the aeration assemblies 44 rotate about a common axis 74 at the same rotational speed in order to cause the water 70 to flow about the basin 12. I prefer that each of the aeration assemblies 44 and 46 include a plurality of aerators, such as the three aerators of FIG. 4, in order to permit one aerator to be serviced and/or replaced while the other associated aerators are operating. This capability further assures flexibility for the waste water facility W since the aeration basin 12 can continue to be operated while the maintenance and/or replacement occurs.
Similarly, I prefer that each of the aeration assemblies 44 and 46 in their supports 64 and 66 be constructed of buoyant material in order to maintain the drives 72 at the same position relative to the surface 68 of the water 70. Those skilled in the art will appreciate that the level of the surface 68 will fluctuate in response to the water input from surge basin 10. Permitting the aeration assemblies 44 and 46 to float on the surface 68 assures that substantially the same driving force will be applied to the water 70 by each of the aerators 56, 58 and 60 at all times. The drives 72 will always extend substantially the same depth into the water 70, so that substantially the same force must be applied for causing rotation of same. Such a construction minimizes imbalances which could occur if the drives 72 extended a different distance into the water 70 at any point in time.
FIGS. 3, 4 and 5 show walkways 76 extending across the top of the basins 12, 14 and 14-16 as a means for further improving access to the various components of the facility W.
FIG. 3 discloses stub walls 78 extending from each intersection of the side walls of basins 10, 12, 14 and 16 which are not interconnected to an adjacent basin. It can be noted in FIG. 3 that the basin 10 shares wall 36 with the basin 12, thereby facilitating construction since the basins 10 and 12 share this common wall. The interconnection of walls 34 and 38, however, is not with another basin with the result that I provide a relatively short wall 78 extending complementarily outwardly therefrom. The stub walls 78 provide additional vertical reinforcement at the point of interconnection of the walls 38 and 34, and also provide an interconnection point in the event expansion proceeds. For example, should it be decided to expand the facility W of FIG. 3, then it would be relatively simple matter to construct another aeration basin 12, either along the wall 32 or the wall 34. This is because at least two walls have already been formed, and the stub walls 78 have already been poured to permit construction of the remaining walls. Once the facility W has been constructed, then expansion can easily occur since each additional facility will share many of the walls poured for the earlier facility, such as shown in FIG. 1.
It can all so be noted from FIG. 3 that the basin 14 shares the wall 40 with the basin 12, and also shares the wall 80 with the basin 16. As with the basin 10, the usage of common or joint walls for adjacent basins facilitates construction while simultaneously minimizing costs. In addition, since the basins 10, 12, 14 and 16 are interconnected to each other through their common walls, then any piping which must be run will, of necessity, be of a relatively short length. Connection of two adjacent basins normally will only require a flow-thru window in the common wall. This again minimizes costs, and piping costs can be rather substantial in a conventional waste treatment facility.
FIG. 3 discloses the rotary clarifier 82 extending from flow box 84 within settling basin 14. A floating aerator 86 is positioned within digester 16 and is of a type well known in the art.
FIG. 6 discloses effluent pipe 88 which causes pumps 90 and 92 of FIG. 3 to direct water from the surge basin 10 into the aeration basin 12. Water to be treated is supplied to surge basin 10 by inlet pipe 85, as best shown in FIG. 3. FIG. 7 discloses lines 94 and 96 which are interconnected by air line 98. Finally, FIG. 8 discloses lines 100 and 102 interconnected by air line 104. The piping of FIGS. 6, 7 and 8 is illustrative of the ability of the waste water facility W to encapsulate piping within the concrete used for forming the walls of the basins. Encapsulation of the piping helps to minimize freezing in cold climates.
While this invention has been described as having a preferred design, those skilled in the art will understand that further uses, modifications, and/or adaptations may be made thereto without departing from the general principles of the invention while still falling within the scope of the claims appended hereto. | A compact waste treatment facility comprises an optional surge basin, an aeration basin, a settling basin, and a digester basin. The basins are interconnected in the order named for therewith providing a sequentially arranged waste treatment facility. Each of the basins is comprised of six integral walls which are substantially equiangularly disposed one to the other so that each basin is hexagonally shaped in plan. Each basin has a wall common with the basin interconnected therewith. Each basin has an assembly for supplying fluid treated therein to the next interconnected basin. An aerator is provided in the aeration basin for causing fluid flow thereabout. | 8 |
BACKGROUND
[0001] Various industrial processes emit emissions containing undesirable pollutants like NOx, CO, VOCs and HAPs. These harmful pollutants may need to be removed from the flue gas before releasing into the atmosphere to meet the Environmental Protection Agency (EPA) requirements. Current technologies enabling industries to remove the pollutants include thermal oxidation (direct fired, recuperative or regenerative) and selective catalytic reduction.
[0002] Existing thermal oxidation technologies are limited to the removal of CO, VOCs and HAPs by heating the flue gas to a temperature greater than 1400 deg. F. Direct fired thermal oxidation has no heat recovery. Recuperative thermal oxidation may recover 60-80% of the heat required to heat the flue gas to a temperature greater than 1400 deg. F. Regenerative thermal oxidation may recover 85-95% of the heat required to heat the flue gas to a temperature greater than 1400 deg. F.
[0003] Existing selective catalytic reduction technologies are believed to be limited to the removal of NOx by either entry into the process system where the temperature is between 500 to 700 deg. F. or heating the flue gas to a temperature between 500 to 700 deg. F. These technologies do not appear to be capable of removing NOx efficiently at a flue gas temperature of less than 480 deg. F.
[0004] Other potential limitations of the current selective catalytic reduction technologies include, but are not limited to: (1) issues of incorporation into systems where space is constrained close to the temperature zone between 480 to 700 deg. F.; (2) revamps of existing systems are limited where turnaround times are not achievable unless the NOx removal product is only by a standalone tie-in; (3) multiple process streams resulting in fluctuating flue gas temperature from ambient to less than 480 deg. F.; and (4) catalyst plugging by the particulate matter in the flue gas.
SUMMARY OF THE INVENTION
[0005] A Cold Selective Catalytic Reduction (CSCR) system and method include selective catalytic reduction and regenerative thermal oxidation to enable removal of Nitrogen (NOx), carbon monoxide (CO), volatile organic compounds (VOCs) and hazardous air pollutants (HAPs) in a single chamber while achieving very high thermal efficiency. Embodiments as described herein include new, lower-temperature selective catalytic reduction systems that use regenerative heat exchange to minimize the amount of additional heat required during the oxidization process. Significant benefits may be obtained for thermal efficiency, as flue gases can be treated with low exhaust gas temperatures of about 200-300 deg. F., therefore allowing the thermal oxidization to take place after economizer or waste-heat recovery units.
[0006] Embodiments as described herein utilize a single chamber to optimize the catalyst, space and structural steel. For example, the CSCR system and method described herein may be a single cylindrical or rectangular chamber which may have inlet and outlet ducts directly coupled to the top and bottom of the chamber, respectively. Flue gas flow may be controlled using dampers/valves and induced draft fan/forced draft fan. From the bottom to top, the chamber may include one or more of the following components: (1) first heat transfer media section; (2) first ammonia distribution section and burners; (3) NOx, CO, VOCs and HAPs catalyst; (4) second ammonia distribution section and burners; and (5) second heat transfer media section. Catalyst used may be in single or multiple layers and may be selected depending on the pollutant constituents to be removed. Further, while a first and second heat transfer media are disclosed, it should be understood that a third, fourth or more heat transfer media section is within the scope of the invention. Further still, while a first and second ammonia distribution section and burners are disclosed, it should be understood that a third, fourth or more ammonia distribution section and burners is within the scope of the invention.
[0007] In one embodiment, the emissions containing pollutant is processed by the CSCR system in cyclical fashion utilizing an up-flow cycle and a down-flow cycle through the CSCR system. These alternating cycles may be repeated in time intervals, for example after every 1-10 minutes, in order to achieve optimal heat recovery. Final cycle time tuning is dependent on a number of variables, including the heat transfer media utilized, and can be field tested for optimization.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] FIG. 1 illustrates a diagrammatic representation of a Cold Selective Catalytic Reduction system according to embodiments as described.
[0009] FIG. 2 illustrates a diagrammatic representation of an up-flow cycle in a Cold Selective Catalytic Reduction system according to embodiments as described.
[0010] FIG. 3 illustrates a diagrammatic representation of a down-flow cycle in a Cold Selective Catalytic Reduction system according to embodiments as described.
DETAILED DESCRIPTION
[0011] The following detailed description illustrates by way of example, not by way of limitation, the principles of the invention. This description will clearly enable one skilled in the art to make and use the invention, and describes several embodiments, adaptations, variations, alternatives and uses of the invention, including what is presently believed to be the best mode of carrying out the invention. It should be understood that the drawings are diagrammatic and schematic representations of exemplary embodiments of the invention, and are not limiting of the present invention nor are they necessarily drawn to scale. While examples are provided herein with respect to the removal of volatile organic compounds (VOCs), hazardous air pollutants (HAPs), carbon monoxide (CO), and oxides of Nitrogen (NOx) via a single chamber cold selective catalytic reduction system and method, it should be appreciated that the principles of the invention described herein may be applicable to other types of pollutants not specifically discussed herein. Further, embodiments as described herein may be combined to remove pollutants, as well as to recover heat.
[0012] Embodiments as described herein utilize a single chamber to optimize the catalyst, space and structural steel. For example, the CSCR system and method described herein may be a single cylindrical or rectangular chamber which may have inlet and outlet ducts directly coupled to the top and bottom of the chamber, respectively. The emissions containing pollutant, such as a flue gas, is processed by the CSCR system in cyclical fashion utilizing a bi-directional gas flow through the CSCR system permitting an up-flow cycle and a down-flow cycle.
[0013] In the up-flow cycle, the flue gas enters through the bottom of the chamber and passes through the first heat transfer media section to be pre-heated. The flue gas may then be heated to the desired final temperature (e.g., 600 to 1100 deg. F.) by the burners and may mix with ammonia and pass up through the catalyst, which removes some or all of the pollutants. In one embodiment, burners and ammonia distribution in the upper section may not be used in this up-flow cycle. Flue gas may then pass up through the heat transfer media where the flue gas may transfer the heat to the heat transfer media and exit the single chamber. Flue gas may exit at approximately the same temperature as the inlet temperature.
[0014] In the down-flow cycle, flue gas enters through the top of the single chamber and passes downward through the heat transfer media to absorb the heat from heat transfer media to be pre-heated. The flue gas may then be heated to the preferred final temperature (e.g., 600 to 1100 deg. F.) by the burners, and may mix with ammonia, and pass down through the catalyst, which removes some or all of the pollutants. In one embodiment, burners and ammonia distribution in the lower section may not be used in the down-flow cycle. Flue gas may then pass down through the heat transfer media where the flue gas may transfer the heat to the heat transfer media and exit the single chamber. Flue gas may exit at approximately the same temperature as the inlet temperature.
[0015] Up-flow and down-flow cycles may be repeated at a desired interval to achieve the heat recovery and pollutant removal at the same time. Final cycle time tuning may depend on the heat transfer media used.
[0016] FIG. 1 illustrates a representative Cold Selective Catalytic Reduction system 1 according to an exemplary embodiment. The system 1 is composed of a chamber 2 to pass the flue gas through the cold selective catalytic reduction process as described herein. The chamber 1 includes two or more heat transfer zones 21 , two or more heating zones 33 , and one or more catalyst reduction zones 41 . The multiple heat transfer zones 21 and heating zones 33 are arranged to permit bi-directional flow of the flue gas for catalytic reduction of the flue gas in both directions. The chamber 2 also includes inlets 15 and outlets 17 along with dampers and valves 11 to accommodate the bi-directional gas flow.
[0017] In one embodiment, the catalytic reduction process components are housed in a single chamber 21 . Embodiments as described herein utilize a single chamber to optimize the catalyst, working space, and structural material. However, as would be understood by a person of skill in the art, the described zones and sections of the chamber may be sub-divided into two or more chambers. The chamber 21 may be a single chamber generally cylindrical, rectangular, square, elliptical, or a combination of these, which may have inlet ducts 15 and outlet ducts 17 directly coupled to the top and bottom of the chamber, respectively. The chamber may be designed to withstand the temperatures associated with the reduction process. For example, the chamber may be of structural steel that is internally lined with a refractory linking, such as brick, castable, ceramic fiber, or a mixture of these. The emissions containing pollutant, such as a flue gas, is processed by the CSCR system in cyclical fashion utilizing a bi-directional air flow producing an up-flow cycle and a down-flow cycle, as described more fully below.
[0018] In one embodiment, the chamber 2 houses two or more heat transfer zones 21 . These zones include a heat transfer media 20 and 60 to recapture some of the energy required to heat the flue gas for the catalytic reduction. As the dirty flue gas enters the system, the gas passes through one or more of the heat transfer zones 21 , thereby pre-heating the gas and requiring less energy to raise the gas to the desired catalytic reduction temperature. As the cleaned flue gas exits the system, the gas passes through one or more of the heat transfer zones 21 ; thereby depositing its heat to be used by the next cycle. The heat transfer zone 21 captures the heat of the gas so that the cleaned flue gas preferably exits the system approximately at or below the temperature it enters the system. The heat transfer zones may be positioned on opposing sides of the catalyst zone 41 so that the separate zones are alternatively used to cool the exit gas and pre-heat the incoming gas and cool, as described more fully below. The heat transfer media may be any material with sufficient heat transfer properties, such as alumina and silica.
[0019] In one embodiment, the chamber 2 houses two or more heating zones 33 to provide the temperature necessary for the selective catalytic reduction. The two or more heating zones may be on opposing sides of the catalyst zone 41 to sufficiently heat the flue gas before entering the catalyst zone 41 while accommodating the bi-directional flow of flue gas through the system.
[0020] A chemical reducing agent 35 may also be added to the flue gas within the heating zones 33 . The chemical reducing agent 35 is injected into the gas stream before the gas enters the catalyst zone 41 , as described below. In an exemplary embodiment, ammonia is used as the chemical reducing agent to reduce NOx, producing Nitrogen and water vapor. The chemical reducing agent 35 may be ammonia in either aqueous or anhydrous form. The chemical reducing agent may be supplied to the chamber through by an injection grid 36 to provide sufficient and even distribution of the chemical throughout the gas stream before entering the catalyst zone. A separate injection grid 36 may be used in each heating zone 33 to supply the chemical reducing agent 35 to the flue gas before it enters the catalyst zone 41 from either direction. The injection system which supplies the injection grid may also be controlled electronically to minimize the amount of un-reacted reducing agent in the gas stream after the reactor. Accordingly, additional monitors, and feedback controls may be used to analyze the cleaned flue gas and control the amount of reducing agent and other reactor parameters, including temperature and residence time. However, the system may not use an ammonia distribution section if the pollutants to be removed do not include Nox, such as a combination of pollutants composed of CO, VOCs and HAPs only.
[0021] In one embodiment, the chamber 2 houses one or more chemical catalyst 40 . Using a catalyst 40 allows oxidation to occur at around 600 deg. F., instead of the usual 1600 deg. F., saving approximately two-thirds on fuel consumption. Hazardous air pollutants that are organic in nature, for example—poly-cyclic aromatic hydrocarbons (PAH) and solvent vapors—are converted through oxidation to carbon dioxide and water. The heated VOC-laden air is passed through the chemical catalysts, such as for example, a bed of solid catalyst, where the VOCS are rapidly oxidized. Alternate embodiments include a single or multiple beds within the chamber of the CSCR system. The chemical catalyst 40 may chosen depending on the pollutants within the passed air stream. For example, systems used to oxidize VOCs may use a metal oxide, such as nickel oxide, copper oxide, manganese dioxide, or chromium oxide. Nobel metals such as platinum and palladium may also be used. The chemical catalyst 40 may be located within the catalyst zone 41 within the chamber 2 . The catalyst zone 41 may be located after the heating zones 33 to permit sufficient heating of the dirty flue gas before entering the catalyst 40 .
[0022] Embodiments as described herein, may also include an air pollution control system. Dusts, mists, and SOx/H2S can all reduce the activity of the catalyst. Dusts and mists can plug the pores of the catalyst support, blocking off the active sites. Sulfur and heavy metals can react with the catalyst, effectively poisoning the catalytic process by forming new compounds and alloys which lack catalytic reactivity. The system may therefore include dust collection and flue gas treatment systems before the flue gas enters the chamber 2 . Additionally or alternatively, guard-beds of catalyst support material which have not been dosed with the metallic catalyst may be used to polish out the stray materials which bypass upstream dust collection and flue gas treatment steps. In one embodiment, the heat transfer media may act as a filter to protect the plugging of the catalyst. Heat transfer media may be configured to plug before the catalyst, thereby protecting the expensive catalyst. The catalyst may cost more than 10 times the cost of the heat transfer media.
[0023] FIGS. 2 and 3 illustrate a representative Cold Selective Catalytic Reduction method of using the Cold Selective Catalytic Reduction system 1 according to embodiments as described herein. Referring to FIG. 2 , illustrating a representative up-flow cycle, the flue gas enters the ductwork 5 and continues through the ductwork 7 . The flue gas from ductwork 7 enters through the damper 10 into section 12 of the single chamber. The flue gas from section 12 passes up through a first heat transfer media section 20 and is pre-heated. The flue gas then passes up through section 32 where it is heated to a preferred final temperature, such as, for example 600-1100 deg. F., by the burners 30 and mixes with ammonia 35 . The temperature may be controlled by thermocouple 25 . The flue gas next passes up through the NOx, CO, VOCs and HAPs catalyst 40 . All or substantially all of the pollutants are removed by the catalyst 40 . In one embodiment, the flue gas then passes up through section 52 , and the burners 45 , ammonia 55 and thermocouple 50 may not be used in this up cycle. Flue gas then passes up through the second heat transfer media section 60 where the flue gas may transfer the heat to the heat transfer media and pass up through section 65 of the single chamber. The flue gas then exits section 65 through damper 70 . The flue gas from the damper 70 may continue through ductwork 75 . The flue gas from ductwork 75 may continue through ductwork 80 . The flue gas from ductwork 80 may enter the centrifugal fan 90 and finally into the stack 95 to be discharged to atmosphere. The centrifugal fan 90 may provide the motive force for the flue gas from ductwork 5 through the single chamber through ductwork 80 and final discharge through the stack 95 .
[0024] After the completion of the up-flow cycle, which may take, for example, 1-10 minutes, the down-flow cycle can be performed. For the down-flow cycle to start, the damper 10 transitions to a closed position, damper 100 transitions to an open position, damper 70 transitions to a closed position, and damper 110 transitions to an open position.
[0025] Referring to FIG. 3 , illustrating a representative down-flow cycle, the flue gas enters the ductwork 5 and continues through the ductwork 105 . The flue gas from ductwork 105 enters through the damper 100 into section 65 of the single chamber. The flue gas from section 65 passes down through the second heat transfer media 60 and is pre-heated. The flue gas then passes down through section 52 where it may be heated to the preferred final temperature, such as for example, 600-1100 deg. F., by the burners 45 and mixed with ammonia 55 . The temperature may be controlled by thermocouple 50 . The flue gas then passes through the NOx, CO, VOCs and HAPs catalyst 40 . All or substantially all of the pollutants may be removed by the catalyst 40 . In one embodiment, the flue gas passes down through section 32 and the burners 30 , ammonia 35 and thermocouple 25 may not be used in this down cycle. Flue gas may then pass down through the first heat transfer media 20 where the flue gas may transfer the heat to the heat transfer media and pass down through section 12 of the single chamber. The flue gas then exits section 12 through damper 110 . The flue gas from the damper 110 may continue through ductwork 107 . The flue gas from ductwork 107 may continue through ductwork 80 . The flue gas from ductwork 80 may enter the centrifugal fan 90 and finally into the stack 95 to be discharged to atmosphere. The centrifugal fan 90 may provide the motive force for the flue gas from ductwork 5 through the single chamber through ductwork 80 and final discharge through the stack 95 .
[0026] After the completion of the down-flow cycle, which may take, for example, 1-10 minutes, another up-flow cycle may start. For the up-flow cycle to start, the damper 10 transitions to an open position, damper 100 transitions to a closed position, damper 70 transitions to an open position, and damper 110 transitions to a closed position. Up-flow and down-flow cycles may be repeated, for example, every 1-10 minutes to achieve heat recovery and simultaneously remove some or all of the pollutants from the emission feed.
[0027] According to various embodiments of the system, different operating parameters and results may be obtained or achieved. For example, the CSCR system and method may be applicable for flue gas at a temperature from ambient to 500 plus deg. F. The CSCR system and method may use less than 5% of the heat required to catalytically remove NOx, CO, VOCs and HAPs by heating the flue gas to the preferred final temperature (600-1100 deg. F.). In one embodiment, the CSCR system and method may remove greater than 90% of NOx and greater than 95% of CO, VOCs and HAPs.
[0028] According to various embodiments of the system, the CSCR system does not have to be installed adjacent to the temperature zone of 500-700 deg. F. It can be installed to site specific space availability. Temperature loss in the CSCR system during the associated method may have no effect on the pollutants removal efficiency. In one embodiment, the CSCR system can be installed while a process system is in operation such that only a tie-in may be required into the process system to start operating the CSCR system and method.
[0029] Embodiments, as described herein, may be applied to handle emissions from multiple process streams resulting in fluctuating flue gas temperature from ambient to less than 500 deg. F., while maintaining the pollutants removal efficiency. For example, using regenerative heat recovery, as described herein, is a practical method for combining multiple effluent gas streams into a single feed stream, allowing one unit to treat a facility or process unit. Embodiments as described herein, can save as much as 95% is fuel consumption, for only a 6% increase in power use, when compared to conventional SCR units. | A system to control the emissions of a fluid stream in a cyclical fashion utilizing an up-flow cycle and a down-flow cycle. The system may include a first inlet and a first outlet at a first end of the system and a second inlet and a second outlet at a second end of the system, a catalyst zone between the first end and second end, two heat transfer zones, at least one heat transfer zone positioned between the catalyst zone and the first end of the system and between the catalyst zone and the second end of the system, and two heating zones, at least one heating zone positioned between the catalyst zone and each of the at least one heat transfer zones. The symmetrical arrangement permits a bi-directional fluid cycle to recover a portion of the energy supplied to the system during each cycle. | 1 |
Latin name of the genus and species claimed: Prunus salicina.
Variety denomination: ‘Suplumfortysix’.
BACKGROUND AND SUMMARY OF THE INVENTION
This invention relates to the discovery and asexual propagation of a new and distinct variety of plum, Prunus salicina cv. ‘Suplumfortysix’. The new variety was first originated by hybridization on Aug. 5, 2007 by Terry A. Bacon as breeder number: ‘PL878RZ’.
The new variety ‘Suplumfortysix’ is characterized by a dark purple dappled skin.
The seed parent is ‘96P024-003-430’ (unpatented), and the pollen parent is unknown. The parent varieties were first crossed in February 2004, with the date of first sowing being February 2005, and the date of first flowering being February 2007. The new plum variety ‘Suplumfortysix’ was first asexually propagated by Terry Bacon near Wasco, Kern County, Calif. in January 2010, by grafting.
The new variety ‘Suplumfortysix’ is distinguished from its seed parent in that the new variety ripens about 18 days after ‘96P024-003-430’ and has a dark purple dappled skin color compared to solid black skin for ‘96P024-003-430’.
The new variety ‘Suplumfortysix’ ripens about 20 days before ‘Angeleno’ (U.S. Plant Pat. No. 2,747) and has a dark purple dappled skin compared to the solid reddish-black skin of ‘Angeleno’ (U.S. Plant Pat. No. 2,747). The new variety Suplumfortysix' ripens about 14 days after ‘Dapple Dandy’ (U.S. Plant Pat. No. 9,254) and has a dappled finish like ‘Dapple Dandy’ (U.S. Plant Pat. No. 9,254) but the color of the new variety is a dark-purple dappled finish compared to the pale-reddish dapple of ‘Dapple Dandy.’
The new variety ‘Suplumfortysix’ has been shown to maintain its distinguishing characteristics through successive asexual propagations by, for example, grafting.
BRIEF DESCRIPTION OF THE PHOTOGRAPH
The accompanying color photographic illustration shows typical specimens of the foliage and fruit of the present new plum variety ‘Suplumfortysix’.
The illustration shows the upper and lower surface of the leaves, a view of the fruit as a whole, an exterior and sectional view of a fruit divided across its suture plane to show flesh color, pit cavity and the stone remaining in place in a 4 year old plant.
The photographic illustration was taken shortly after being picked and the colors are as nearly true as is reasonably possible in a color representation of this type.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Throughout this specification, color names beginning with a small letter signify that the name of that color, as used in common speech is aptly descriptive. Color names beginning with a capital letter designate values based upon The R.H.S. Colour Chart published by The Royal Horticultural Society, London, England, 1986.
The descriptive matter which follows pertains to a 4 year old ‘Suplumfortysix’ plants on Nemaguard rootstock, grown in the vicinity of Wasco, Kern County, Calif., during 2013, and is believed to apply to plants of the variety grown under similar conditions of soil and climate elsewhere.
TREE
General: (Measurements taken on a 4 year old tree unless otherwise noted.)
Size .—Medium. Reaches a height of approximately 3 meters with normal pruning. Spread .—Approximately 3 meters. Vigor .—Medium. Growth .—Semi-upright. Productivity .—Productive. Form .—Vase formed. Bearer .—Regular. Fertility .—Unknown. Canopy density .—Medium. Hardiness .—Hardy in all fruit growing areas of California. Winter chilling requirement is approximately 700 hours at or below 7.2 C. Disease resistance/susceptibility .—Under close observation in Kern County, Calif., no particular plant/fruit disease resistance/susceptibility has been observed. Insect resistance/susceptibility .—Under close observation in Kern County, Calif., no particular plant/fruit insect resistance/susceptibility has been observed.
Trunk: (Measurements at approximately 30 cm above soil line on mature tree).
Length .—Approximately 61 cm. Diameter .—Approximately 14 cm. Texture .—Medium shaggy, increases with age of tree. Trunk color .—About Medium Grey-Brown 199B to Medium Greyed-Orange 173B; becomes darker with age.
Branches: (Measurements at approximately 90 cm above soil line.)
Length .—Approximately 240 cm. Size .—Diameter approximately 9 cm. Texture .—Medium, Shaggy. Color .—Varying between about Medium Grey-Brown 198B to Medium Greyed-Orange 173B; becomes darker with age. Lenticels .—Present.
Lenticels:
Density .—About 2/cm 2 . Color .—About Medium Grey-Brown 199B. Size .—Medium, about 1 mm×2mm. Length.— 3 mm. Width.— 2 mm.
Flowering shoots: (Data taken in September at mid-point of current season growth.)
Size .—Average diameter approximately 4 mm. Color .—Topside: About Dark Greyed-Orange 176A. Underside: About Dark Greyed-Orange 176A. Internode length .—Medium; approximately 2 cm. Midway on flowering shoot. Flowering shoot lenticels .—Medium, about 8/cm2. Color: About Medium Greyed-Orange164B. Diameter: Approximately 0.5 mm. Texture: Smooth. Flowering shoot leaf buds .—Shape: Conical. Width: Approximately 1.5 mm. Length: Approximately 2 mm. Color: About Dark Greyed-Orange 166A. Texture: Smooth. Flowering shoot flower buds .—Shape: Ovoid. Width: Approximately 1.1 mm. Length: Approximately 2 mm. Color: About Dark Greyed-Orange 166A. Number of buds per node: Usually 2-4. Texture: Smooth. Density of flower buds .—Medium, about 2-4/node. Density of leaf buds .—Medium, about 1-4/node. Flower bud distribution .—On spurs and one year old shoots and older wood. Ratio of wood ( leaf ) buds to flowering buds.— 2/2 on nodes. Anthocyanin intensity .—None or very slight.
FOLIAGE
Leaves: (Data taken in September on fully expanded leaves at mid-point of the current season growth).
Size .—Medium. Average length .—Medium; approximately 80 mm without petiole. Average width .—Medium; approximately 43 mm. Thickness .—Medium, about 0.8 mm. Color .—Upper surface: About Dark Yellow-Green 147A. Lower surface: About Medium Yellow-Green 148C. Form .—Broad obovate. Tip .—Cuspidate. Base .—V-shaped. Margin .—Crenate. Venation .—Pinately net veined. Vein color .—About Dark Yellow-Green 147D. Surface texture .—Smooth (upper and lower). Leaf blade ( ratio of length to width ).—Medium, About 2:1. Shape in the cross section .—Concave. Angle at apex .—Small. Profile .—Up folded. Leaf blade tip .—Curved downwardly. Angle of tip .—Acute. Undulation of margin .—Slight.
Petiole:
Texture .—Smooth. Strength .—Strong. Average length .—Medium; approximately 13 mm. Average diameter .—Approximately 1.5 mm. Color .—About Light Yellow-Green 147D. Thickness .—Medium, About 1.1 mm.
Stipules:
Texture .—Smooth (upper and lower surfaces). Number/leaf bud .—Approximately 0-2 per leaf bud when present. Typical length .—Approximately 8 mm. Color .—About Medium Yellow-Green 147C. Persistence .—Falls off.
Leaf glands:
Form .—Globose. Average number.— 0-2. Position .—On leaf base, opposite. Average size .—Medium; approximately 0.5 mm. Color .—About Dark Greyed-Orange 165A.
FLOWERS
General:
Flower blooming period .—First bloom: Approximately Mar. 1, 2013 in Wasco, Calif. Full bloom: Approximately Mar. 4, 2013 in Wasco, Calif. Location of first bloom .—Top of tree. Location of full bloom .—Mid-section of the canopy. Time of bloom .—Medium from approximately March 1-March 4. Duration of bloom .—Medium; approximately 14 days. Diameter of fully opened flower .—Medium, approximately 7 mm. Flower aroma .—Slight aroma. Shape .—Rosaceous.
Peduncle:
Strength .—Strong. Length .—Medium; approximately 12 mm. Diameter .—Slender; approximately 1.5 mm. Color .—About Medium Yellow-Green 144B. Pubescence .—Absent.
Petals:
Number.— 5. Arrangement .—Free. Length .—Approximately 9 mm. Diameter .—Approximately 6 mm. Shape .—Obovate. Apex shape .—Rounded. Base shape .—Narrows at point of attachment. Color of inner and outer surface .—Approximately White 155D. Surface texture .—Smooth. Margins .—Slightly undulating, entire. Frequency of flowers with double petals .—None. Size .—Medium. Claw length .—Medium, about 1.5 mm. Margin waviness .—Weak. Base angle .—Narrow. Division of upper margin .—Entire. Pubescence of inner surface .—Absent. Pubescence of outer surface .—Absent.
Sepals:
Number.— 5. Length .—Approximately 3 mm. Diameter .—Approximately 3 mm. Shape .—Triangular. Color .—About Medium Yellow-Green 144A. Surface texture .—Smooth. Margins .—Entire. Positioning .—Adpressed to petals. Pubescence of inner surface .—Absent. Pubescence of outer surface .—Absent. Frequency of flowers with double sepals .—None.
Stamens:
Number .—Usually 25-30. Average length .—About 1-10 mm. Filament color .—About White 155D. Anther color .—About Medium Greyed-Yellow 162A. Flower pollen color .—About Medium Greyed-Yellow 162A when dried. Position .—Perigynous.
Pistil:
Color .—About Medium Yellow-Green 144B. Number .—Usually one, occasionally two. Average length .—Approximately 6-9 mm. Ovary diameter .—Approximately 1 mm. Pubescence .—None. Stigma extension in comparison to anthers .—Usually below anthers. Style frequency of supplementary pistils .—Few.
Receptacle:
Depth .—Medium. Pubescence of inner surface .—Absent. Pubescence of outer surface .—Absent.
Ovary:
Color .—About Medium Yellow-Green 144B. Pubescence .—Absent.
Style:
Color .—About Medium Yellow-Green 144B. Pubescence .—Absent.
FRUIT
General: (Description taken near Wasco, Kern County, Calif. on August 12).
Date of first pick.— Approximately August 8. Date of last pick.— Approximately August 20. Maturity when described .—Firm-mature. Season ripening .—Medium, approximately August 8 to August 20. Position of maximum diameter .—Center. Symmetry about the suture .—Symmetric or slightly assymetric.
Size:
Length ( stem end to apex ).—Approximately 75 mm. Diameter in line with suture plane .—Approximately 75 mm. Diameter perpendicular to suture plane .—Approximately 70 mm. Average weight .—Approximately 180 gm.
Form:
Viewed from apex .—Rounded. Viewed from side, facing suture .—Rounded, slightly elongated. Viewed from side, perpendicular to suture .—Rounded, slightly elongated.
Apex shape: Rounded.
Fruit stem cavity:
Shape .—Elongated in suture plane. Depth .—Shallow; Approximately 0.8 cm. Breadth .—Approximately 1 cm. Width .—Narrow, approximately 1 cm.
Fruit stem:
Length .—Medium; approximately 8 mm. Diameter .—Approximately 3 mm. Color .—About Light Yellow-Green 147D. Adherence to stone .—Medium.
Fruit skin:
Thickness .—Medium, approximately 0.8 mm. Adherence to flesh .—Medium. Surface texture .—Smooth. Pubescence .—None. Bloom .—Medium-heavy. Ground color .—About Medium Yellow-Green 148B to Medium Greyed-Orange163C. Overcolor .—Dapple, About Dark Greyed-Purple 187B to Dark Greyed-Purple 187A. Taste .—Neutral. Reticulation .—Slight. Roughness .—Absent. Tenacity .—Tenacious to flesh. Tendency to crack .—None in wet season.
Flesh:
Ripens .—Evenly. Texture .—Crisp-juicy. Fibers .—Few. Flavor .—Mildly Sweet. Brix .—Approximately 19°. Juice .—Abundant. Aroma .—Slight fruity aroma. Color .—About Dark Red 53A. Anthocyanin color of flesh .—Strongly expressed throughout evenly. Acidity .—Medium. Sugar content .—High. Eating quality .—Good. Stone/flesh ratio .—Small. Firmness .—Medium.
Pit cavity size:
Length .—Approximately 25 mm. Diameter perpendicular to suture plane .—Approximately 18 mm. Diameter in line with suture .—Approximately 10 mm. Color .—About Dark Red 53A.
Fruit use: Fresh market.
Fruit shipping and keeping quality: Good.
Stone:
Stone freeness .—Cling. Degree of adherence to flesh .—Medium. Stone size .—Size: Medium. Size compared to Fruit: Small. Length: Medium, approximately 25 mm. Diameter in line with suture plan: Approximately 18 mm. Diameter perpendicular to suture plane: Approximately 10 mm. Width of Stalk End: Medium, Approximately 8 mm. Angle of Stalk end: Right angle. Hilum: Oval. Stone form .—Viewed from side: Oval with flat base. Viewed from ventral end: Flattened. Viewed from Stem end: Oval. Stone shape .—Base shape: Nearly straight. Apex shape: Rounded with small point. Stone surface .—Rough with irregular shallow furrows. Stone halves .—Nearly symmetrical. Stone ridges .—Rough, rounded. Stone outgrowing keel .—Well-developed. Stone tendency to split .—Almost none. Stone color .—About Medium Greyed-Orange 174A. Position of maximum .—Middle. Sides .—Nearly equal. Pits .—Angular. Ventrical edge .—Narrow. Dorsal edge .—Narrow continuous. | A new and distinct plum tree variety, Prunus salicina, cv. ‘Suplumfortysix’ is characterized by a dark-purple dappled skin. | 0 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates in general to detecting systems for detecting the combustion condition of an internal combustion engine, and more particularly to detecting systems of a type which detects abnormal combustion (or misfiring) of the engine by treating an integrated value of the pressure (or combustion pressure) in a cylinder of the engine.
2. Description of the Prior Art
In order to clarify the task of the present invention, one conventional detecting system of the above-mentioned type will be outlined, which is disclosed in Japanese Utility Model First Provisional Publication 64-15937.
In the conventional system of the publication, the combustion pressure is integrated within a given crankangle range (viz., from TDC (top dead center) to ATDC 30° (viz., 30° after top dead center), and the integrated value is compared with a reference value to judge whether or not abnormal combustion has occurred in a cylinder of the engine. It is said that such detecting system can detect the abnormal combustion more precisely than other conventional detecting systems, such as a system in which the time when the combustion pressure exhibits the maximum value or the increasing rate of the combustion pressure is used as a parameter for detecting the abnormal combustion.
However, even the detecting system disclosed by the publication has failed to exhibit a satisfied detecting ability particularly in a case wherein the engine is under a low load and low rotation speed condition. That is, under such condition, the combustion in each cylinder is unstable, and the combustion pressure tends to exhibit a marked dispersion. Furthermore, the integrated value of the combustion pressure derived under such condition fails to show a marked difference from that derived under normal combustion, and thus, it is difficult to keep the high detecting ability throughout substantially whole operation range of the engine.
SUMMARY OF THE INVENTION
It is therefore an object of the present invention to provide a combustion condition detecting system which can precisely detect the abnormal combustion of the engine throughout substantially whole operation range of the engine.
It is another object of the present invention to provide a combustion condition detecting system which can precisely detect the abnormal combustion of the engine even when the engine is under a low load and low rotation speed condition.
According to the present invention, there is provided a combustion condition detecting system of an internal combustion engine. The system comprises first means for detecting the pressure in a cylinder of the engine; second means for setting an integral range in a crankshaft angle in accordance with a rotation speed of the engine; third means for integrating the pressure within the integral range thereby to derive an integrated value; and fourth means for judging whether or not an abnormal combustion occurs in the cylinder by comparing the integrated value with a reference value; wherein, in a given engine speed side, the integral range is set to appear after a given crankangle position where the pressure in the cylinder exhibits the maximum.
BRIEF DESCRIPTION OF THE DRAWINGS
Other objects and advantages of the present invention will become apparent from the following description when taken in conjunction with the accompanying drawings, in which:
FIG. 1 is a schematic view of an internal combustion engine to which the present invention is practically applied;
FIG. 2 is a flowchart showing programmed operation steps executed in a computer for detecting the abnormal combustion of the engine; and
FIG. 3 is a graph showing the characteristic of an integrated value of combustion pressure with respect to the relationship between the crankangle of the engine and the pressure in a cylinder of the engine.
DETAILED DESCRIPTION OF THE INVENTION
In FIG. 1, there is shown an internal combustion engine 1 to which the present invention is practically applied. The engine 1 is an in-line four cylinder type. An air cleaner 2, a throttle chamber 3, a throttle valve 9 and an intake manifold 4 are arranged in the illustrated known manner to constitute an intake system of the engine 1. An exhaust manifold 5, an exhaust duct 6, a three-way catalytic converter 7 and a muffler 8 are arranged in the illustrated known manner to constitute an exhaust system of the engine 1.
The throttle valve 9 is controlled by an accelerator pedal (not shown). As is known, the throttle valve 9 adjusts the amount of air fed to the engine 1.
The four cylinders #1, #2, #3 and #4 have each an ignition plug (not shown) exposed to the combustion chamber. Pressure sensors 10a, 10b, 10c and 10d are respectively installed in the four cylinders #1, #2, #3 and #4. Each pressure sensor detects the pressure prevailing in the associated cylinder. The pressure sensors 10a, 10b, 10c and 10d may be of a type as shown in Japanese Utility Model First Provisional Publication 63-17432 or a type as shown in Japanese Patent First Provisional Publication 4-81557. That is, the type shown in '432 publication acts also as a seat of the ignition plug, and the type shown in '557 publication has a probe directly exposed to the combustion chamber and senses the absolute pressure in the chamber.
Designated by numeral 11 is an optical type crankangle sensor which issues a detecting signal each time a crankshaft (not shown) of the engine 1 comes to a predetermined angular position. The crankangle sensor 11 is in association with a cam shaft (not shown) which is, as is known, synchronously operated with the crankshaft.
In accordance with the present invention, the crankangle sensor 11 issues a reference angular signal "REF" every 180 degrees in crankangle, which corresponds to the phase difference in stroke between two cylinders which make the stroke in succession. Furthermore, the crankangle sensor 11 issues an angular position signal "POS" every unit angle (1 degree or 2 degrees) of the crankshaft.
As shown in FIG. 1, an air flow meter 12 is arranged upstream of the throttle valve 9, which measures the amount of air fed to the engine 1.
The information signals issued from the pressure sensors 10a, 10b, 10c and 10d, the crankangle sensor 11 and the air flow meter 12 are fed to a control unit 13 which includes a microcomputer. That is, by analyzing the information signals, the control unit 13 controls the amount of fuel fed to the engine 1 and the ignition timing of the ignition plugs.
As will be apparent from the following, the control unit 13 is arranged to detect an abnormal combustion (or misfiring) of the engine 1.
FIG. 2 is a flowchart showing programmed operation steps which are executed in the computer of the control unit 13 to judge the combustion condition of each cylinder of the engine 1.
It is to be noted that the operation steps of the flowchart are executed, as an interruption subroutine, every a given small time (preferably, each several tens of microseconds).
In the flowchart, at step S1, an integral range (viz., integral time) for which the pressure "P" sensed by each pressure sensor 10a, 10b, 10c or 10d is integrated is set in accordance with an engine rotation speed "Ne" which is derived based on the information signal from the crankangle sensor 11. As is seen from the graph of the step S1, one integral range set in a higher engine speed side is large enough for containing the "TDC" (viz., top dead center) crankangle position, while, the other integral range set at a lower engine speed side is so small as not to contain the "TDC" crankangle position. More specifically, with decrease in the engine rotation speed "Ne", the integral range is gradually shifted toward the "ATDC" (viz., after top dead center) side and gradually reduced in size.
As will be understood from the graph of FIG. 3, in an engine speed lower than a predetermined speed set near the idling speed of the engine 1, the integral range (viz., 50° to 60° in crankangle) is set to appear after a certain crankangle position "Pθmax" where the pressure in a cylinder exhibits the maximum under normal combustion operation of the engine 1. That is, the integral range appears after the crankangle position "Pθmax" by a predetermined degree, for example, by 10° in crankangle. For ease of understanding, the crankangle position "Pθmax" will be referred to the "maximum pressure crankangle position" in the following description.
That is, the integral range which has been set to contain both the "TDC" crankangle position and the maximum pressure crankangle position "Pθmax" at the higher engine speed side is gradually shifted toward the "ATDC" side (or delayed crankangle position) as the engine rotation speed "Ne" reduces. That is, with decrease in the engine rotation speed "Ne", the integral range comes to a range which does not contain the "TDC" crankangle position, and comes to a range which does not contain both the "TDC" crankangle position and the maximum pressure crankangle position "Pθmax" and finally comes to the range which, as has been described hereinabove in conjunction with the graph of FIG. 3, appears after the maximum pressure crankangle position "Pθmax" by the predetermined degree in crankangle.
Referring back to the flowchart of FIG. 2, at step S2, the existing crankangle position "θ" is read from the information signal from the crankangle sensor 11. Then, at step S3, a judgment is carried out as to whether or not the crankangle position "θ" is within the integral range which has been set at step S1. If No, that is, when the judgment is so made that the crankangle position "θ" is not within the set integral range, the operations flow goes to step S4. At this step, an after-mentioned integral value "IMEP" is reset to 0 (zero) and the operation flow goes to end.
If Yes, at step S3, that is, when the judgment is so made that the crankangle position "θ" is within the set integral range, the operation flow goes to step S5. At this step, the combustion pressure "P" in a cylinder #1, #2, #3 or #4 is read from an output signal issued from an associated pressure sensor 10a, 10b, 10c or 10d. Of course, the output signal has been subjected to A/D (analog/digital) conversion before being fed to the computer of the control unit 13.
Then, at step S6, the combustion pressure "P" is gradually integrated to renew an integrated value "IMEP" for the combustion pressure. Then, at step S7, a judgment is carried out as to whether or not the integration calculation has come to the terminal end of the set integral range. If No, that is, when the integration calculation is still in the middle of the set integral range, the operation flow goes to end.
While, if Yes at step S7, that is, the judgment is so made that the integration calculation has come to the terminal end and thus a completely integrated value "IMEP" has been provided, the operation flow goes to step S8. At this step, a judgment is carried out as to whether or not the integrated value "IMEP" is equal to or greater than a reference value. It is to be noted that this reference value is a variable value and is set based on the engine load and the engine speed "Ne".
If No at step S8, that is, when the judgment is so made that the integrated value "IMEP" is smaller than the reference value, the operation flow goes to step S9. At this step, it is judged that an abnormal combustion (or misfiring), which would cause a certain drop of the combustion pressure in the integral range, has taken place. Although not shown in the drawings, alarm means is provided which issues an alarm when the number of times of the abnormal combustion judgment exceeds a predetermined number.
If Yes at step S8, that is, when the judgment is so made that the integrated value "IMEP" is equal to or greater than the reference value, the operation flow goes to step 10. At this step, it is judged that a normal combustion, which would allow a satisfied combustion pressure in the integral range, has been kept. The operation flow goes to end.
As is known to those skilled in the art, in a higher engine speed side, a marked difference of combustion pressure is provided between the abnormal and normal combustion conditions particularly in a crankangle range around "TDC" position and/or a range just after "TDC" position.
In view of this phenomenon, in the present invention, the integral range set in the higher engine speed side is large enough for containing the "TDC" crankangle position and the position just after the "TDC" position, as is seen from the graph of step S1 of FIG. 2. Accordingly, the combustion condition can be precisely detected in the higher engine speed side.
While, in a lower engine speed side near the idling speed, the difference of the maximum combustion pressure between the abnormal and normal combustion conditions is very small and the combustion is relatively unstable. Thus, even if the combustion pressure is integrated in a crankangle range which includes the maximum pressure crankangle position, the respective integrated values in the abnormal and normal combustion conditions fail to bring about a marked difference therebetween.
However, in accordance with the present invention, in the lower engine speed side, the integral range is gradually shifted toward the "ATDC" side or the delayed crankangle position as the engine rotation speed reduces. That is, near the idling speed of the engine, the integral range is set to appear after the maximum pressure crankangle position "Pθmax" where the pressure in a cylinder exhibits the maximum under normal combustion operation of the engine. Thus, even in the lower engine speed side, the integrated value "IMEP" can exhibit a marked level difference between the abnormal and normal combustion conditions of the engine.
That is, in a low load condition of the engine, the intermolecular density of fuel is small and thus the combustion time is prolonged. Accordingly, in the crankangle range after the maximum pressure crankangle position "Pθmax", the combustion pressure level is largely varied in accordance with the existing combustion condition. Thus, if, like in the present invention, the integral range is set to match with the prolonged combustion time, the integrated value "IMEP" becomes to exhibit a marked level difference between the abnormal and normal combustion conditions of the engine even in the lower engine speed side. As has been mentioned in the part of step S1, the integral range is set in accordance with the engine rotation speed "Ne".
Accordingly, in the present invention, detection of the abnormal combustion in each cylinder can be precisely carried out throughout substantially whole operation range of the engine, by using the integrated value "IMEP".
In the following, modifications of the present invention will be described.
Although, in the above-mentioned embodiment, the integral range is gradually varied in accordance with the engine rotation speed "Ne", the integral range may have two ranges. That is, in this case, the engine rotation speed "Ne" is grouped into two, that is, a higher speed group and a lower speed group. In the higher speed group, one integral range is set which contains the "TDC" crankangle position and a range just after the "TDC" position, and in the lower speed group, the other integral range is set to appear after the crankangle position where the pressure in a cylinder exhibits the maximum under normal combustion operation of the engine.
Furthermore, if desired, the integral range may be varied in accordance with an engine load as well as the engine rotation speed "Ne". In this case, in the lower engine speed and lower engine load, the integral range is set to appear after the maximum pressure crankangle position. | A combustion condition detecting system of an internal combustion engine, comprises a first device for detecting the pressure in a cylinder of the engine; a second device for setting an integral range in a crankshaft angle in accordance with a rotation speed of the engine; a third device for integrating the pressure within the integral range thereby to derive an integrated value; a fourth device for judging whether or not an abnormal combustion occurs in the cylinder by comparing the integrated value with a reference value; and a fifth device for issuing an alarm when the fourth device judges occurrence of the abnormal combustion. In accordance with the invention, in a lower engine speed side near the idling speed, the integral range is set to appear after a given crankangle position where the pressure in the cylinder exhibits the maximum. | 6 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] The present invention claims priority from U.S. Provisional Application Serial No. 60/298,724, entitled “Dolly Wheel Assembly With An Integrated Suspension,” filed Jun. 15, 2001.
TECHNICAL FIELD
[0002] The present invention relates generally to a wheel assembly with an integrated suspension for use in a variety of all terrain and high speed applications with the integrated suspension being configured to allow the wheel assembly to move upwardly and rearwardly in response to an impact force. More specifically, the present invention relates to dolly wheels for use with a vehicle that provides maneuverability resulting in what is termed zero turn capability. The present invention also offers advantages when related to vehicle wheels, including both fixed position and steered.
BACKGROUND OF THE INVENTION
[0003] Dolly wheels are commonly used on vehicles or other devices which operate at low speeds (0-10 m.p.h.) as well as on industrial trucks and dollies and other equipment where it is advantageous to have zero turn capabilities. The wheels on such dolly wheel suspensions are subjected to relatively high impact forces when they engage an obstruction. These impact forces typically increase as a function of increasing speed and weight or load and operation in rough surface engagement conditions.
[0004] Shock absorbing dolly wheel suspensions, which help reduce the transmission of impact forces from the ground engaging wheels to the vehicle load, or load supported thereby, currently exit. Many of these shock absorbing dolly wheel suspension systems utilize a variety of springs attached to different support members to minimize the effect of impact forces that are encountered by the dolly wheels on the vehicles. While these dolly wheel suspension systems provide satisfactory performance, they normally require a relatively large devoted envelope within which to locate the suspension within the vehicle. This large devoted envelope requires structuring the vehicle to accommodate the larger suspension, which thus increases the overall cost of the vehicle. There are also dolly wheel systems that use a short spring or elastomeric compression component to dampen impact loads. However, while compact in size, these systems are relatively limited in suspension travel and travel dampening characteristics that are generally accomplished with a shock absorber utilized within a larger system.
[0005] Further, suspension systems for vehicle wheels of the non-dolly wheel type have been developed with a variety of different configurations. These suspension systems are incorporated into a variety of different vehicles, including automobile, motorcycle and the like. Current suspension systems are typically configured such that they are located inwardly of the vehicle wheel and their components move generally along the axis of the wheel. Because these suspension systems are located inwardly of the vehicle wheel, they require a relatively large amount of space. These suspension systems provide satisfactory performance. However, the amount of space required to accommodate the suspension system is disadvantageous for many uses.
[0006] It would thus be advantageous to provide a dolly wheel suspension system that provides significant travel, and requires significantly less space without sacrificing performance. It would also be advantageous to provide a suspension system for a fixed location wheel or a wheel of steering capability that requires significantly less space without sacrificing performance.
SUMMARY OF THE INVENTION
[0007] It is therefore an object of the present invention to provide a wheel suspension system for a vehicle that will effectively absorb the shocks incident to travel of the vehicle over irregular road surfaces.
[0008] It is another object of the present invention to provide a dolly wheel suspension system in which the dolly wheel is mounted for generally up and down movements as it encounters irregularities in road surface and is arranged with a spring and shock absorber to yieldably resist upward movement of the wheel and to absorb road shocks resulting in the minimum upward component of movement of the vehicle itself.
[0009] It is yet another object of the present invention to provide a wheel suspension system that can be packaged in a much smaller area within a vehicle than prior suspension systems.
[0010] It is a related object of the present invention to provide a wheel suspension system that can be utilized with dolly wheels having zero turn capabilities.
[0011] It is still a further object of the present invention to provide a dolly wheel suspension system that includes the full shock absorption and spring action that is currently present in existing automotive vehicles.
[0012] It is still another object of the present invention to provide a suspension system for a fixed location wheel, a controlled steered wheel of a vehicle, or an unrestrained dolly wheel that is fully integrated within the rim of the wheel.
[0013] In accordance with the above and the other objects of the present invention, a wheel suspension system is provided. In the case of a dolly wheel, the suspension system includes a dolly wheel, a wheel carrier arm, and a dolly wheel spindle rotationally secured to a frame element of the vehicle. The dolly wheel spindle has a generally vertical axis of rotation and the wheel carrier arm and the dolly wheel rotate about the axis of rotation. The wheel carrier arm is rotatably secured to the dolly wheel spindle and acts as a swing arm for the dolly wheel. The wheel carrier arm has a first end that is pivotally secured to the dolly wheel spindle and extends downwardly from the pivot point defined by the connection of the wheel carrier arm to the dolly wheel spindle. The wheel carrier arm has a method for rotatably mounting the dolly wheel being generally located in its mid body. The wheel carrier arm has a second end that is remote from the first end with the second end being secured to a first end of a shock absorber. The wheel carrier arm is moveable about the pivot point thereby compressing or extending the shock absorber. The shock absorber incorporates a spring and is rotatably secured at a second end to an extending arm of the dolly wheel spindle. The dolly wheel has an outer periphery and the shock absorber is located within an area defined by the outer periphery of the dolly wheel to minimize the space needed for the suspension system.
[0014] Other objects and features of the present invention will become apparent when viewed in light of the detailed description of the preferred embodiment when taken in conjunction with the attached drawings and appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] [0015]FIG. 1 is an exploded view of a wheel suspension system in accordance with a preferred embodiment of the present invention;
[0016] [0016]FIG. 2 is a schematic side view of a dolly wheel suspension system in accordance with a preferred embodiment of the present invention;
[0017] [0017]FIG. 3 is a schematic side view of the dolly wheel suspension system of FIG. 2 illustrating the operation of the suspension system when the wheel is subjected to an impact force in accordance with a preferred embodiment of the present invention;
[0018] [0018]FIG. 4 is a schematic side view of a dolly wheel suspension system in accordance with another preferred embodiment of the present invention;
[0019] [0019]FIG. 5 is a schematic side view of the dolly wheel suspension system of FIG. 4 illustrating the operation of the suspension system when the wheel is subjected to an impact force in accordance with a preferred embodiment of the present invention;
[0020] [0020]FIG. 6 is cross-sectional front view of the dolly wheel suspension system of FIG. 4 in accordance with a preferred embodiment of the present invention;
[0021] [0021]FIG. 7 is a cross-sectional front view of a standard steer wheel suspension system utilizing the general suspension components as shown in FIGS. 4 and 5 in accordance with a preferred embodiment of the present invention; and
[0022] [0022]FIG. 8 is a schematic front view of a standard wheel suspension system utilizing the general suspension components of FIG. 2 and FIG. 3 in accordance with a preferred embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0023] Referring now to FIGS. 1 to 3 , which illustrate a wheel suspension system 10 in accordance with a preferred embodiment of the present invention. As will be understood, the wheel suspension system 10 is preferably intended for use with a dolly wheel that provides, what are termed in the art, zero turn capabilities. However, it will be understood that the disclosed wheel suspension system can be utilized with other types of wheels, including wheels that are fixed and have controlled steering capabilities. Additionally, the disclosed suspension system is preferably incorporated into a vehicle, such as an automotive vehicle, a trailed vehicle, or a mobility vehicle. The dolly wheel suspension system 10 includes a dolly wheel 12 , a dolly wheel spindle assembly 14 , a wheel carrier arm 16 , and a shock absorber 18 .
[0024] The dolly wheel 12 includes a wheel rim 20 having an outer periphery 22 . A tire 24 is disposed around the outer periphery 22 of the wheel rim 20 and is secured to the wheel rim 20 . The tire 24 has an outer periphery 26 , which is intended to engage the ground. The wheel rim 20 has a wheel hub 28 secured thereto, as would be clearly understood by one of skill in the art. The tire 24 is preferably configured for off road capability.
[0025] The dolly wheel spindle assembly 14 includes an upwardly extending pin portion 30 which is secured to a top portion 32 , which extends over top of the tire 24 . The pin portion 30 is secured to a support portion 34 (FIG. 2) of a vehicle. The pin portion 30 of the dolly wheel spindle assembly 14 is secured through at least one bearing 36 to the support portion 34 . The dolly wheel spindle assembly 14 is thus free to spin about a dolly wheel spindle axis 38 to respond to the direction of travel of a vehicle.
[0026] The dolly wheel spindle assembly 14 preferably carries all of the suspension components in the direction of travel of the wheel and of the end of the vehicle, as generally indicated by the arrow 40 . The wheel carrier arm 16 is pivotally connected to the top portion 32 of the dolly wheel spindle assembly 14 by a pin 42 to define a pivot point 43 thereat. The pivot point 43 allows the wheel carrier arm 16 to pivot with respect to the dolly wheel spindle assembly 14 , as required. The wheel carrier arm 16 is secured to the shock absorber 18 , which carries a spring 46 to maintain the wheel carrier arm 16 in a secure and load carrying position with respect to the dolly wheel spindle assembly 14 . The wheel carrier arm 16 is also secured to the wheel hub 28 by a bearing shaft 44 .
[0027] The wheel carrier arm 16 preferably has a bend 45 formed therein to allow a portion of the wheel carrier arm 16 and the shock absorber 18 to fit inside the wheel rim 20 . In this configuration, inside means that at least a portion of the wheel carrier arm 16 as well a portion of the shock absorber 18 are located within the wheel rim 20 when the dolly wheel 12 is viewed from the front. In other words, the bend 45 locates a portion of the wheel carrier arm 16 and the shock absorber 18 inside the outermost side portion of the tire 24 or in the volume defined by the wheel rim. The dolly wheel spindle assembly 14 also includes an extending portion 47 that is also preferably constructed to function as a mud scraper within the wheel rim 20 .
[0028] The shock absorber 18 is preferably a spring shock and includes the spring 46 . The shock absorber 18 is preferably set for operating load and acts in compression. As will be understood, the shock absorber 18 thus urges the wheel carrier arm 16 downwardly and forwardly such that the dolly wheel 12 engages the ground. The shock absorber 18 is secured to the wheel carrier arm 16 and to the dolly wheel spindle assembly 14 by a plurality of securing bolts 48 . The shock absorber 18 has a first end 50 that is secured to the wheel carrier arm 16 and a second end 52 that is secured to a flange portion 35 . The flange portion 35 extends downwardly from the top portion 32 of the dolly wheel spindle assembly 14 . The first end 50 of the shock absorber 18 is preferably pivotally secured to the wheel carrier arm 16 . Similarly, the second end 52 of the shock absorber 18 is preferably pivotally secured to the dolly wheel spindle assembly 14 .
[0029] As shown, the suspension system 10 is preferably provided such that the shock absorber 18 is located within the outer periphery 26 of the tire 24 . More preferably, the shock absorber 18 is located within the outer periphery 22 of the wheel rim 20 . Additionally, at least a portion of the wheel carrier arm 16 is located within the outer periphery 22 of the wheel rim 20 . Preferably, a substantial portion of the wheel carrier arm 16 is located within the outer periphery 22 of the wheel rim. The dolly wheel 12 and the wheel rim 20 are preferably of a sufficient diameter to accommodate the suspension needed by the vehicle.
[0030] It will be understood that it is also possible to locate the wheel carrier arm 16 either within the outer periphery 22 of the wheel rim 20 or outside the outer periphery 26 of the tire 24 , depending on packaging needs. Moreover, the pivot point 43 for the wheel carrier arm 16 can be positioned outside the outer periphery 26 of the tire 24 and the wheel rim 20 for more linear path of the dolly wheel 12 and thus a greater length of suspension travel.
[0031] In the embodiment shown in FIGS. 1 through 3, a substantial portion of the wheel carrier arm 16 is located within the periphery of the wheel rim 20 . Moreover, the suspension system 10 is located below the dolly wheel spindle axis 38 . The suspension operates equally in all directions of vehicle motion with the turning of the dolly wheel 12 to the direction of travel. This is because the dolly wheel 12 spins toward its direction of travel, thereby taking the suspension system 10 with it in that direction of travel. It will be understood that when utilized on a vehicle, a pair of dolly wheels will preferably be utilized. The operation of each dolly wheel and its associated suspension is preferably the same and thus the description of the structure and operation of one will apply equally to the operation of the other.
[0032] Referring now to FIG. 3, which illustrates the operation of the suspension system 10 in accordance with the present invention. As shown, when the tire 24 contacts a bump or rock 60 in the road or ground, a force can impact the tire 24 , which results in upward and rearward motion, as generally indicated by arrow 70 , in such a manner as to absorb forward motion impact. This upward and rearward motion is shown in FIG. 3. In order to effectuate this motion, the wheel carrier arm 16 rotates about the pivot point 43 and the shock absorber 18 compresses against the force of the spring 46 . Moreover, because the shock absorber 18 is pivotal about its first end 50 and its second end 52 , it can rotate during compression to accommodate for the length of travel of the wheel carrier arm 16 .
[0033] Referring now to FIGS. 4 through 6, which illustrate another embodiment of the suspension system 10 in accordance with the present invention. In the embodiment shown in FIG. 4, the dolly wheel spindle assembly 14 and the wheel carrier arm 16 are configured differently than the embodiment shown in FIGS. 2 to 3 . As shown in FIG. 4, the flange portion 35 of the dolly wheel spindle assembly 14 extends further downwardly than in the embodiment of FIGS. 2 and 3 such that its axis pin 43 , rotatably securing the wheel carrier arm 16 is located within the outer periphery 26 of the tire 24 . With this configuration, the pivot point determined by axis pin 43 is located within the outer periphery 22 of the wheel rim 20 . Moreover, the first end 52 of the shock absorber 18 is pivotally secured to an extension portion 62 that is integrally formed with the dolly wheel spindle assembly 14 .
[0034] [0034]FIG. 5 illustrates the operation of the suspension system 10 of FIG. 4. The operation of the suspension system 10 is substantially the same as in the embodiment described above in connection with FIGS. 1 through 3. Specifically, when the tire 24 contacts a bump or rock 60 in the road or ground, a force can impact the tire 24 , which results in upward and rearward motion in such a manner as to absorb forward motion impact. In order to effectuate this motion, the wheel carrier arm 16 rotates about the pivot point 43 and the shock absorber 18 compresses against the force of the spring 46 . Moreover, because the shock absorber 18 is pivotal about its first end 50 and its second end 52 , it can rotate during a compression to accommodate the travel of the wheel carrier arm 16 .
[0035] [0035]FIG. 6 illustrates the wheel carrier arm 16 and the shock absorber 18 being located within an area or volume defined by the wheel rim 20 . Thus, as shown, in the front view, the shock absorber 18 and the wheel carrier arm 16 are located within the area defined by the wheel rim 20 . Similarly, the wheel carrier arm 16 , the axis pin 43 , and the shock absorber 18 are located within the outer periphery 22 of the wheel rim 20 when viewed from the side view.
[0036] [0036]FIGS. 7 and 8 illustrate alternative embodiments of the preferred suspension system 10 for use with a standard steering system. As shown, a tire 80 is secured to a vehicle frame 82 . The vehicle frame 82 includes a tie rod 84 extending therefrom to effectuate standard steering. The vehicle frame 82 includes a vehicle king ping 84 secured thereto. The king pin 84 includes a generally vertical axis of rotation 86 . The king pin 84 is in communication with an assembly 88 of the vehicle frame 82 for securing a wheel carrier 90 . The wheel carrier 90 has a wheel carrier arm 92 pivotally secured thereto on axis 101 . A shock absorber 94 and associated spring 96 is disposed between one end 98 of the wheel carrier arm 92 and an upper end 100 of the wheel carrier 90 . The wheel carrier arm 92 is secured to a wheel hub 102 on an axis 103 , as will be understood by one of skill in the art. The operation of the suspension system 10 for the standard steering, as illustrated in FIGS. 7 and 8, is the same as described above in connection with dolly wheel steering.
[0037] In the embodiment shown in FIG. 7, the wheel carrier arm 92 and the shock absorber 94 are located entirely within the area or volume defined by the wheel rim 104 . Thus, as shown, in the front view, the shock absorber 94 and the wheel carrier arm 92 are located within the area defined by the wheel rim 104 . Similarly, the wheel carrier arm 92 , the axis pin 101 , and the shock absorber 94 are located within the outer periphery 108 of the wheel rim 104 when viewed from the side view. In the embodiment shown in FIG. 8, the wheel carrier arm 92 and the shock absorber 94 are located entirely outside the tire 80 and the wheel rim 104 in the front view. However, the wheel carrier arm 92 and the shock absorber 94 are located inside the outer periphery 110 of the tire 80 when viewed from the side view.
[0038] In accordance with the above, the suspension system 10 has maximum ability in all directions of the vehicle steer condition. Further, the angle of the king pin axis 86 does not change with movement of the suspension system 10 . The disclosed suspension system 10 provides a compact, cost effective design and in particular is an excellent, well-packaged suspension for a mobility vehicle. It will be appreciated that a free acting dolly wheel 12 , as shown in FIGS. 1 through 6, with this suspension system 10 could also be controlled to effectuate fully controlled steering with the use of the suspension system described herein. Alternatively, the disclosed suspension system 10 could be used with a standard wheel, as disclosed in FIGS. 7 and 8, rather than a dolly wheel.
[0039] While a preferred embodiment of the present invention has been described so as to enable one skilled in the art to practice the present invention, it is to be understood that variations and modifications may be employed without departing from the purview and intent of the present invention, as defined in the following claims. Accordingly, the preceding description is intended to be exemplary and should not be used to limit the scope of the invention. The scope of the invention should be determined only by reference to the following claims. | A wheel suspension system for a vehicle includes a vehicle wheel having a wheel rim and a tire secured to the wheel rim. The wheel is secured to a frame portion of the vehicle by a spindle assembly. The spindle assembly includes a wheel carrier arm pivotally secured thereto at a pivot point, such that said wheel and said wheel carrier arm rotate together about an axis of rotation defined by said pivot point. The wheel carrier arm is in communication with a shock absorption device. The shock absorption device is located within a space defined by the wheel, such that the shock absorption spring device is hidden when the vehicle wheel is viewed from a side direction. The shock absorption spring device compresses upon an impact force contacting said vehicle wheel. In the most compact form, the wheel carrier arm and the shock absorbing spring device is packaged within the wheel rim volume such that both are hidden when the vehicle wheel is viewed from a front direction. | 1 |
BACKGROUND OF THE INVENTION
This invention relates to a valve apparatus included in a dispensing unit for dispensing a beverage, such as a syrup or the like, in particular, to controlling of a flow of the beverage.
Various dispensing units of the type are already known. For example, a dispensing unit as a post-mixed beverage dispenser is disclosed in U.S. Pat. Nos. 493,441 and 4,688,701 issued to Jason K. Sedam et al and assigned to The Coca-Cola Company. The dispensing unit is for dispensing a beverage contained in a bottle and comprises a valve apparatus for controlling of a flow of the beverage. The valve apparatus comprises a body defining a plurality of beverage paths which is for conducting the beverage.
Each of the beverage paths has an inlet end, an outlet end, and an intermediate portion therebetween. The beverage is introduced into the inlet end and is discharged from the outlet end through the intermediate portion.
Each of the beverage paths is provided with an adjusting element in addition to valve mechanism which is for opening and closing it. The adjusting element is for adjusting a flow rate of the beverage in the beverage path. Each of the valve element and adjusting element extends through the body from the intermediate portion to a front end of the body. The valve element can be operated by an operating lever which is provided on a front end of the body. The adjusting element can also be operated at the front end of the body.
It is advantageous that the beverage dispenser can be placed in a limited space because an external form of the beverage dispenser may be compact.
However, it is assumed that the beverage leaks from each of the beverage paths of the valve apparatus through clearances which are left around the valve and the adjusting elements, respectively. In order to seal all of the clearances, a plurality of sealing elements must be provided in relation to each of the beverage paths. Therefore, it is necessary to use a great number of the sealing elements. Nevertheless, there is great danger of leakage of the beverage.
In addition, the valve apparatus is relatively large in a size thereof. This is because the valve and the adjusting elements are placed at positions which are different from one another.
SUMMARY OF THE INVENTION
It is therefore an object of the present invention to provide a valve apparatus which is readily capable of preventing a beverage from leakage thereof in spite of including an adjusting element as well as a valve element.
It is another object of this invention to provide a valve apparatus of the type described, which is capable of being manufactured in a small size.
Other objects of this invention will become clear as the description proceeds.
According to this invention, there is provided a valve apparatus for use in a dispensing unit for dispensing a beverage through a beverage path having a particular portion. The valve apparatus includes a valve body defining the beverage path, controlling means coupled to the particular portion for controlling a flow of the beverage in the particular position, and operating means coupled to the valve body and the controlling means for operating the controlling means. In the valve apparatus, the controlling means comprises a valve member, a force transmission member, urging means, and restriction means. The valve member is coupled to the valve body and is movable, in a predetermined direction, between an open and a close position which are for opening and closing the particular portion, respectively. The valve member has a first end facing the particular portion and a second end opposite to the first end in the predetermined direction. The force transmission member is coupled to the valve body and the operating means and is movable in the predetermined direction. The force transmission member faces the second end of the valve member in the predetermined direction. The urging means is coupled to the valve body and the force transmission member and is for urging the force transmission member towards the second end of the valve member to locate the valve member at the close position. The restriction means is coupled to the valve body and is for restricting movement of the valve member in a predetermined sense which is opposite to the urging means. The restriction member determines the open position.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a plan view of a dispensing unit including a valve apparatus according to an embodiment of this invention;
FIG. 2 is a sectional view of the dispensing unit taken along a line 2--2 in FIG. 1;
FIG. 3 is a sectional view of a part of the dispensing unit taken along a line 3--3 in FIG. 1;
FIG. 4 is a sectional view for use in describing operation of the dispensing unit illustrated in FIG. 1;
FIG. 5 is a perspective view of a water conduction member included in the dispensing unit of FIG. 1; and
FIG. 6 is a view for use in describing a dispensing unit comprising the valve apparatus illustrated in FIG. 1.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to FIGS. 1 through 4, a valve apparatus according to an embodiment of the present invention is for use in a dispensing unit which is for dispensing a beverage, such as a syrup drink diluted with dilution water and/or carbonated water in the manner known in the art. The valve apparatus comprises a body 11 which is fixed to a frame (not shown) of the dispensing unit by bolts 12 and which will be referred to as a local body or body member. The body 11 defines a syrup path 13 at a central position thereof and dilution water and carbonated water paths 14 and 15 which are placed at left and right sides thereof, respectively. Each of the syrup, the dilution water, and the carbonated water paths 13, 14, and 15 is referred to as a beverage path and is communicated with a nozzle 16 which is provided at a lower end of the body 11. The body 11 may be made of a combination of various parts.
The syrup path 13 has, an upper end thereof, a connecting opening 17 connected to a syrup bottle 18 which is placed on an upper portion of the body 11. The syrup bottle 18 is removable from the body 11 The dilution water path 14 is connected to a dilution water source (not shown) through a dilution water pipe (not shown). Similarly, the carbonated water path 15 is connected to a carbonated water source (not shown). Therefore, it is possible to discharge the syrup, the dilution water, and carbonated water through the nozzle 16.
The syrup path 13 has, between the nozzle 16 and the connecting opening 17, an intermediate portion as a particular portion provided with a valve mechanism 22 which is capable of opening and shutting the syrup path 13. Each of the dilution and the carbonated paths 14 and 15 is provided with another valve mechanism 23 which is similar to the valve mechanism 22.
Description will proceed to only the first-mentioned valve mechanism 22 because those valve mechanisms are similar to one another. A valve hole 11a is made in the body 11 to communicate with the particular portion of the syrup path 13. The valve mechanism 22 comprises valve and force transmission members 24 and 25. The valve member 24 is placed in the valve hole 11a to be movable in each of first and second senses 26 and 27 which are opposite to one another. The valve member 24 has a packing 28 at an end thereof in the second sense 27. The packing 28 faces the intermediate portion of the syrup path 13 and is for opening or closing the syrup path 13 with the valve member 16 moved in each of the first and the second senses 26 and 27. The valve member 24 is urged in a first sense 26 by a first compression spring 29 which is as additional urging arrangement between the body 11 and the valve member 24.
A sealing member 30 is fixed to the body 12 and is in slidable contact with the valve member 24 to seal a gap 31 left therebetween. It is to be noted in this connection that FIG. 1 illustrates a case where the valve member 24 is placed at a close position at which the syrup path 13 is closed at a particular portion thereof by the valve member 24.
The valve apparatus further comprises an adjusting screw 32 of a cylindrical tube which defines a through hole 32a. The adjusting screw 32 is screwed in a cylindrical screw hole 11b which is made in the body 11 as a through hole to communicate with the valve hole 11a. Therefore, the adjusting screw 32 has a position which is adjustable in the first and the second senses 26 and 27 by rotation thereof. In addition, it is readily possible by a small force to operate the adjusting screw 32. A combination of the body 11 and the adjusting screw 32 is referred to as a valve body.
The force transmission member 25 is inserted in the adjusting screw 32 and extends in the first and the second senses 26 and 27 to have first and second ends 25a and 25b which extend outside of the adjusting screw 32 in the first and the second senses 26 and 27.
A second compression spring 33 is placed inside the adjusting screw 21 and is referred to as urging arrangement. The second compression spring 33 is for urging the force transmission member 25 in the second sense 27. As a result, the first end 25a of the force transmission member 25 is brought in press contact with the valve member 24 to push the valve member 24 towards the close position. In this connection, the second compression spring 33 has an urging force which is greater than that of the first compression spring 29. Therefore, the valve member 24 is placed at an open position to open the syrup path 13 when the force transmission member 25 is not received with external force.
A stopper 34 is fixed to an axial end of the adjusting screw 32 to be movable in each of the first and the second senses 26 and 27 dependent on the adjusting screw 32. The stopper 34 is for determining the open position. At the open position, the valve member 24 is in engagement with the stopper 34 in the first sense 26. In this connection, it is a matter of course that the valve member 24 opens the syrup path 13. The open position can be moved in each of the first and the second senses 26 and 27 by rotating the adjusting screw 32. Therefore, it is possible to adjust an opening of the syrup path 13 into a desired value thereof. The stopper 34 is referred to as a restriction arrangement.
The body 11 is provided with an operating lever 35 at a front surface thereof. The operating lever 35 has a middle portion rotatably supported to a supporting portion 36 through a horizontal shaft 37. A substantial end portion of the operating lever 35 is in removable engagement with a shaft 38 which is supported to the second end 25b of the force transmission member 25.
When the operating lever 35 is pushed as depicted at an arrow 39, the force transmission member 25 is moved in the first sense 26. In response, the valve member 24 is also moved in the first sense to open the syrup path 13. As a result, the syrup flows from the syrup bottle 18 into the syrup path 13 and then is supplied to the nozzle 16 through the water conduction member 41. In this event, movement of the operating lever 35 is detected with a detection switch 42 operated by an arm 43 which is fixed to the operating lever 35.
Although detailed description is omitted for simplification of the description, each of the dilution water and the carbonated water paths 14 and 15 comprises construction which are similar to that of the syrup path 13. Therefore, it is possible to supply the beverage of suitable mixing among the syrup, the carbonated water, and the dilution water through the nozzle 6. It is a matter of course that concentration of the beverage may be adjusted by each adjusting screw 32.
The syrup bottle 18 is of a cassette type which is detachably attached to the body 11. CO 2 gas can be supplied to the syrup bottle 18 through a gas path 44 and a gas tube (not shown) connected to the gas path 44. The gas path 44 is connected to a check unit 50 which will presently be described.
The check unit 50 comprises a unit body 51 fixed to the body 11 by screw members 52. The unit body 51 defines a space portion 53 which extends upwardly and downwardly. The space portion 53 has an upper opening and a lower opening which is closed by a cover member 54 screwed in the lower opening. The upper opening of the space portion 53 is connected to an inlet port 56 which is for being connected to the gas tube. The space portion 53 has a lower portion communicated with the syrup bottle 18 through the gas path 44. As a result, a combination of the gas path 44 and the space portion 53 is formed in a U-shape as will become clear from FIG. 2.
The check unit 50 further comprises first and second check valves 61 and 62 which are arranged in series in the space portion of the unit body 51. The first check valve 61 is placed at a high position. The second check valve 62 is placed at a low position which is lower than the high position.
The first check valve 61 comprises valve seat and valve body members 63 and 64. The valve seat member 63 is fixed to the unit body 51. The valve body member 64 is held in a central portion of the valve seat member 63. A seal ring 65 is for sealing a clearance around the valve seat member 63.
The valve seat member 63 has a plurality of small through holes 66 which are arranged along a circle. Each of the small through holes 66 is for permitting the CO 2 to gas pass therethrough. On the other hand, the valve body member 64 is of rubber and comprises a flange portion 67 which faces the small through holes 66. The flange portion 67 is for checking the CO 2 gas flow upwardly. It is a matter of course that the first check valve 61 permits the CO 2 gas flow downwardly.
Although detailed description is omitted for simplification of the description, the second check valve 62 comprises structure which is similar to that of the first check valve 62. A numeral 68 is representative of a filter which is well known in the art.
With this structure, a counterflow of the syrup is surely prevented by the first and the second check valves 61 and 62.
Referring to FIG. 5 together with FIGS. 2 and 3, the water conduction member 70 comprises a cylindrical portion 71 of a central portion thereof, and a plate portion 72 which outwardly extends from an end of the cylindrical portion 71. The cylindrical portion 71 is communicated with the syrup path 13 and defines a plurality of discharging ports 73 which are radially directed at the vicinity of a lower end thereof. Therefore, the syrup is discharged inside the nozzle 16 through each of the discharging ports 73.
The plate portion 72 has a plurality of projections 74 formed on a peripheral surface thereof. Two adjacent ones of the projections 74 produce a groove 75 therebetween. The plate portion 72 comprises two table portions 76 which are placed at an upper surface thereof with an angular space left therebetween. Each of the table portions 76 has an upper surface which is flat.
The water conduction member 41 is fixedly placed in the nozzle 16 so that the table portions 76 face outlet ends of the dilution and the carbonated paths 14 and 15, respectively.
When the dilution and the carbonated water are discharged from the outlet ends of the dilution water and the carbonated water paths, they collide with the upper surfaces of the table portions 76 to thereby be spread in various directions. After that, the dilution and the carbonated water are discharged inside the nozzle 16 through the grooves 75. As a result, the syrup is enveloped in the dilution and the carbonated water in the nozzle 16. Therefore, mixing is favorably carried out between the syrup, the dilution water, and the carbonated water.
Attention will be directed to the dispensing unit referring to FIG. 6. The dispensing unit comprises a coupler 81 connected to a pump 82 through a first supplying pipe 83. The coupler 81 is for removably connecting a portable tank 84 to the supplying pipe 83 and has a function in which the supplying pipe 83 is closed when the portable tank 84 is removed from the coupler 81. The portable tank 84 is for containing a drinking water.
The pump 82 is connected to an end of a refrigerant pipe 85 and has operation which is controlled by a control unit 86 with reference to operation of the detection switch 42. The refrigerant pipe 85 is passed through a refrigerant water contained in a refrigerant water tank 87. Second and third supplying pipes 88 and 89 are connected to another end of the refrigerant pipe 85 through an electromagnetic three-way-valve 93 which is well known in the art. The second supplying pipe 88 is connected to a carbonator 94 through a check valve 95. The carbonator 94 is provided with a float switch 96 therein.
The dispensing unit further comprises three valve apparatus 97 which are similar to the above-mentioned valve apparatus shown in FIGS. 1 through 4. The third supplying pipe 89 is connected to the dilution water path 14 (FIG. 3) of each of the valve apparatus 97. More particularly, the third supplying pipe 89 is branched into a plurality of pipe portions which are connected to the valve apparatus 97, respectively.
A CO 2 tank 98 is connected to the carbonator 94 through a gas pipe 101. The carbonated water is produced from a drinking water and the CO 2 gas in the carbonator 94. The gas pipe 101 is provided with reducing and check valves 102 and 103 which are inserted thereto. The reducing valve 102 is provided with an indicator 104 which is for indicating a primary pressure of the gas pipe 101. The reducing valve 102 is for reducing a pressure of the CO 2 gas into 0.4 kg/cm 2 .
A branched pipe 105 is connected to the gas pipe 101 between the reducing and the check valves 102 and 103. The branched pipe 105 extends through the reducing valve 107 and an operating cock 108 and is branched into a plurality of pipe portions which are connected to syrup tanks S1, S2, and S3, respectively. Each of the syrup tanks S1, S2, and S3 corresponds to the above-mentioned syrup bottle 18 shown in FIG. 2. The syrup tanks S1, S2, and S3 are connected to the valve apparatus 97, respectively.
The carbonated water can be taken from the carbonator 94 through the pipe 106. The pipe 106 is branched into a plurality of pipe portions which are connected to the carbonated water paths of the valve apparatus 97, respectively.
The refrigerant water tank 87 is provided with an evaporator 108 which extends along an internal surface thereof. As will be known in the art, the evaporator 108 is included in a refrigerant circuit which comprises a compressor 111 and a condenser 112. In this connection, the refrigerant water has a temperature which is controlled in the refrigerant water tank 87 to be about 0°.
Description will be made about operation of the dispensing unit. When predetermined operation is carried out after a cup 113 is placed on a tray (not shown), the detection switch 42 is operated to thereby actuate both of the pump 82 and the three-way-valve 93. The pump 82 supplies the drinking water to the carbonator 94 and the valve apparatus 97. Responsive to supplying of the drinking water, the carbonator 94 produces the carbonated water to thereby supply the carbonated water to the valve apparatus 97. As a result, the drinking water, the carbonated water, and the syrup are supplied to the valve, apparatus.
When the float switch 96 detects a decrease of the water level in the carbonator 94, the pump 82 is driven to supply the drinking water into the carbonator 94. In this event, the three-way-valve 93 is not driven. | In a valve apparatus comprising a controlling arrangement which is for controlling a flow of a beverage in a beverage path, the controlling arrangement comprises a valve member which is movable between an open and a close position for opening and closing the beverage path and which is urged to the close position through a force transmission member by a compression spring. When the force transmission member is moved against the urging arrangement, the valve member becomes movable towards the open position. However, movement of the valve member is restricted at the open position by a stopper. Preferably, the stopper has a position which can be adjusted by operating of an operator or a user. | 1 |
RELATED APPLICATIONS
This application is related to U.S. patent application Ser. No. 09/173,101, filed Oct. 15, 1998, and entitled Spool Support Assembly For The Optical Fiber Of A Laser Module (Potteiger 5 - 1 ), now U.S. Pat. No. 6,007,018 issued Dec. 28, 1999 the disclosure of which is incorporated herein by reference.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to support devices that support electro-optical devices and assemblies during automated manufacturing and testing procedures. More particularly, the present invention relates to support devices that retain a laser source and a segment of optical fiber in an orientation suitable for automated testing on an assembly line.
2. Description of the Prior Art
There are many different applications that utilize optical fibers. In an optical fiber system, a laser source is typically used to generate a light signal. The light signal is then propagated through an optical fiber that is attached to the laser source.
In the telecommunications industry, solid state laser sources are commonly manufactured and sold as part of premanufactured module assemblies. In these modules, a solid state laser is attached to a segment of optical fiber. The optical fiber terminates at its free end with some type of fiber optic connector. In this manner, the laser module can be readily integrated into an existing electro-optical system. An example of such a laser module is the Laser 2000 Module, manufactured and sold by Lucent Technologies of Murray Hill, N.J.
There are many different types of premanufactured laser modules currently available. Depending upon the needs of a customer, a premanufactured laser module can be manufactured with a variety of different laser sources, optical fiber types, optical fiber lengths and termination connectors.
Regardless of the type of laser module being manufactured, one of the problems commonly encountered in the manufacturing process is that of the handling of the laser module. As has been previously explained, the laser module contains a laser source and a length of optical fiber that extends from that laser source. The length of the optical fiber often can be up to 80 inches. Such a length of optical fiber is difficult to manipulate. The optical fiber can easily tangle and protrude from an assembly in a random direction. As such, laser modules are not readily adapted to automated manufacturing methods because the random position of the optical fiber would makes automated part positioning and testing very difficult. Instead, due to the awkwardness of the optical fibers, laser modules are often handled and tested by hand during manufacture. In such a manner, the optical fiber can be properly oriented as needed. Although such hand manipulated manufacturing and testing procedures are effective, they are highly labor intensive and expensive.
A need therefore exists for a laser module handling system that can hold a laser module in a set position during manufacturing and testing, thereby allowing automated manufacturing procedures to be used.
SUMMARY OF THE INVENTION
The present invention is a support assembly for retaining a laser module of the type having a solid state laser, an optical connector and an optical fiber extending between the laser and the optical connector. The support assembly includes a baseplate having a top surface and a bottom surface. A removable spool extends upwardly from the top surface of the baseplate, wherein the spool is sized to have the optical fiber wound therearound. A laser receptacle is disposed on the top surface of the baseplate. The laser receptacle is sized to receive the solid state laser in a first predetermined position and orientation. A connector holder is also disposed on the top surface of the baseplate. The connector holder receives and retains the optical connector at a second predetermined position and orientation. As a result, the support assembly retains the solid state laser and the optical connector at known positions that are suitable for automated testing, while the spool retains the optical fiber in a neatly wound condition during the automated testing procedures.
BRIEF DESCRIPTION OF THE DRAWINGS
For a better understanding of the present invention, reference is made to the following description of an exemplary embodiment thereof, considered in conjunction with the accompanying drawings, in which:
FIG. 1 is an exploded view of an exemplary embodiment of an assembly in accordance with the present invention;
FIG. 2 is a perspective view of the exemplary embodiment of FIG. 1 shown in an assembled condition;
FIG. 3 is a perspective view of the bottom of the exemplary embodiment of FIG. 2; and
FIG. 4 is a perspective view of the exemplary embodiment of FIG. 2, shown within an automated testing station.
DETAILED DESCRIPTION
Although the present invention device and method can be used to hold many different assemblies that have long wire leads or long optical fiber leads, it is particularly useful in the manufacture and assembly of laser modules that have long optical fiber leads. Accordingly, by way of example, the present invention device and method will be described within the context of manufacturing and testing a laser module.
Referring to FIG. 1, a prior art laser module 10 is shown. The laser module 10 is a Laser 2000 Module manufactured by Lucent Technologies, the assignee herein. The shown laser module 10 contains a solid state laser 12 . The laser 12 itself has multiple conductive leads 14 that extend outwardly from opposing sides of the solid state laser 12 . The conductive leads 14 are used to both power and control the laser 12 during its operation. The conductive leads 14 are also used to power, control and test the laser 12 during its manufacture.
An optical fiber 16 extends from the solid state laser 12 . The optical fiber 16 receives the laser light generated by the solid state laser 12 and propagates that light to its free end. The optical fiber 16 can be of any length. However, in many applications the length of the optical fiber 16 is typically less than 80 inches. The free end of the optical fiber 16 terminates with an optical connector 18 . Many different types of optical connectors 18 can be used depending upon the needs of a customer ordering the laser module 10 .
The present invention is an assembly designed to retain the laser module 10 in a set position while the laser module 10 is tested and shipped by the manufacturer. The assembly includes a baseplate 20 , a spool 22 and a connector holder 24 . Each of these elements is fabricated from a static dissipative material to prevent the build-up of electrostatic charge. In the preferred embodiment, the baseplate 20 , spool 22 and connector holder 24 are molded from a conductive plastic.
The shown exemplary embodiment of the baseplate 20 is rectangular in shape. Such a shape is merely exemplary and it will be understood that other shapes can be used. A laser test aperture 26 is disposed in one part of the baseplate 20 . Corner supports 28 are formed on opposing sides of the laser test aperture 26 . The corner supports 28 define a laser receptacle 30 , wherein the corner supports 28 receive the corners of the solid state laser 12 and retain the solid state laser 12 in a known fixed position over the laser test aperture 26 . Lead supports 32 are present on the baseplate 20 on opposite sides of the laser test aperture 26 . The lead supports 32 support the conductive leads 14 of the solid state laser 12 when the laser 12 is positioned within the laser receptacle 30 between the corner supports 28 . An illustration of the solid state laser 12 in position over the laser test aperture 26 is shown in FIG. 2 .
Still referring to FIG. 1, it can be seen that the connector holder 24 has posts 34 that extend downwardly toward the baseplate 20 . The posts 34 engage corresponding holes 36 that are present in the baseplate 20 . The posts 34 on the connector holder 24 engage the baseplate holes 36 with a slight interference fit, thereby selectively connecting the connector holder 24 to the baseplate 20 . A plurality of different sets of holes can be formed in the baseplate 20 . This allows the connector holder 24 to be positioned at a variety of different positions on the baseplate 20 as desired. It also makes it easy to alter the configuration of the overall assembly as different models of laser modules 10 are received.
The connector holder 24 is configured to receive the optical connector 18 being used as part of the laser module 10 . As different optical connectors 18 are used, different connector holders 24 can be substituted on the baseplate 20 . The connector holder 24 shown contains a pawl 37 . The pawl 37 applies a slight bias to the optical connector 18 after the optical connector 18 has been placed within the connector holder 24 . The bias of the pawl 37 helps retain the optical connector 18 in place.
The optical fiber 16 that extends from the solid state laser 12 to the optical connector 18 is wound around a spool 22 . The spool 22 contains a cylindrical wall 38 around which the optical fiber 16 is wound. The top of the cylindrical wall 38 terminates with a segmented flange 39 that prevents the wound optical fiber 16 from passing over the top of the cylindrical wall 38 . A cross element 40 spans across the center of the spool 22 in the same general plane as the flange 39 .
Locking tabs 42 extend outwardly from the bottom edge of the cylindrical wall 38 . The locking tabs 42 pass through slots 44 in the baseplate 20 and engage the bottom surface of the baseplate 20 , as will later be explained.
The baseplate 20 is designed to receive the spool 38 . Two arcuate elements 46 , 48 extend upwardly from the baseplate 20 . The two arcuate segments 46 , 48 are arranged as part of a common circle and define a hub structure 50 . The hub structure 50 is sized to fit within the cylindrical wall 38 of the spool 22 . An open area 52 exists between the arcuate segments 46 , 48 of the hub structure 50 . As will later be explained, the open area 52 allows space for a person's fingers to engage and turn the cross element 40 of the spool 22 when the spool 22 is engaged with the baseplate 20 .
Guide segments 54 are positioned at various points on the baseplate 20 around the hub structure. The guide segments 54 pass around the outside of the spool 22 after the spool 22 is attached to the baseplate 20 . The guide segments 54 , therefore prevent the optical fiber 16 from unwinding from the spool 22 after the spool 22 is attached to the baseplate 20 .
Slots 44 are disposed at various points around the two arcuate segments 46 , 48 . The slots 44 are positioned and shaped to receive the locking tabs 42 on the bottom of the spool 38 . As the spool 22 is attached to the baseplate 20 , the locking tabs 42 pass through the slots 44 . As the spool 38 is rotated, the tabs 42 engage the bottom surface of the baseplate 20 , thereby creating a mechanical connection between the spool 22 and the baseplate 20 .
Referring now to FIG. 2, it can be seen that the solid state laser 12 and its conductive leads 14 are held in one set position by the corner supports 28 and lead supports 32 of the baseplate 20 . The optical fiber 16 extending from the solid state laser 12 winds around the spool 22 . The flange 39 at the top of the spool 22 prevents the optical fiber 16 from raising off of the spool 22 . Additionally, the guide elements 54 that surround the spool 22 prevent the optical fiber 16 from unwinding from the spool 22 , to any point beyond the bounds of the baseplate 20 . Optional secondary guidance elements 59 can be provided at various points between the spool 22 and the optical connector 18 to help prevent the optical fiber 16 from protruding beyond the bounds of the baseplate 20 .
From FIG. 2, it can also be seen that the cross element 40 of the spool 22 aligns across the open area 52 between the two arcuate segments 46 , 48 of the hub structure 50 on the baseplate 20 . The open area 52 between the two arcuate segments 46 , 48 therefore provides room for a person to engage the cross-element 40 with his/her fingers and turn the spool 22 . By turning the spool 22 , a person can cause the spool 22 to either engage or disengage the baseplate 20 .
Referring to FIG. 3, it can be seem that various T-slots 63 are formed on the bottom surface 64 of the baseplate 20 . The use of T-slots is merely exemplary and it should be understood that any type of mechanical connection configuration can be used.
Referring now to FIG. 4, it can be seen that the baseplate 20 of the assembly is adapted to connect to a metal boat 70 . The metal boat 70 contains T-protrusions that selectively engage the T-slots on the bottom of the baseplate 20 . In the manufacturing procedure, the present invention assembly and metal boat 70 are placed on an automated track 72 . The automated track 72 takes the assembly to an automated testing station. Once in the automated testing station a test socket actuator 74 raises up though the metal boat 70 and the baseplate 20 and contacts the solid state laser 12 through the laser test aperture 26 (FIG. 1) that is present in the baseplate 20 . The test socket actuator 74 lifts the solid state laser 12 out of the laser receptacle 30 defined by the corner supports 28 and biases the conductive leads 14 of the laser 12 against a fixed test head 76 . The test head 76 electrically interconnects with the conductive leads 14 , wherein power and diagnostic test commands can be read to the solid state laser 12 . Guidance holes 78 can optionally be positioned proximate the laser receptacle 30 . The fixed test head 76 may contain guide posts (not shown) that engage the guidance holes 78 thereby ensuring accurate alignment between the solid state laser 12 and the fixed test head 76 .
As the solid state laser 12 is interconnected with the fixed test head 76 , the optical connector 18 is positioned next in an optical receiver, via an integrating sphere 79 . As such, the test station can control the inputs to the solid state laser 12 and can monitor the output of the laser module. Accordingly, the entire laser module can be tested at the test station in an automated fashion. When the testing diagnosis is over, the test socket actuator 74 retracts and again lowers the solid state laser 12 into the corner supports 28 on the baseplate 20 .
After the laser module has successfully passed testing, the baseplate 20 is removed from both the metal boat 70 and the assembly track 72 . The entire assembly can then be packaged and shipped as a unit. Consequently, the assembly used to retain the laser module during testing can also be used to retain the laser module during shipping. The customer can then remove the laser module from the assembly and recycle the assembly back to the manufacturer.
By using a single assembly to retain the laser module during both testing and shipping, the laser module need not be handled. Accordingly, the potential of damage to the laser module is reduced. Simultaneously, the degree of labor and expense needed to package the laser module is reduced.
It will be understood that the embodiment of the present invention specifically shown and described is merely exemplary and that a person skilled in the art can make alternate embodiments using different configurations and functionally equivalent components. For example, the shape and position of the various elements on the baseplate can be varied to meet the needs of a specific application. All such alternate embodiments are intended to be included in the scope of this invention as set forth in the following claims. | A support assembly for retaining a laser module of the type having a solid state laser, an optical connector and an optical fiber extending between the laser and the optical connector. The support assembly includes a baseplate having a top surface and a bottom surface. A removable spool extends upwardly from the top surface of the baseplate, wherein the spool is sized to have the optical fiber wound therearound. A laser receptacle disposed on the top surface of the baseplate. The laser receptacle is sized to receive the solid state laser in a first predetermined position and orientation. A connector holder is also disposed on the top surface of the baseplate. The connector holder receives and retains the optical connector at a second predetermined position and orientation. As a result, the support assembly retains the solid state laser and the optical connector at known positions that are suitable for automated testing, while the spool retains the optical fiber in a neatly wound condition during the automated testing procedures. | 6 |
CROSS REFERENCE TO RELATED APPLICATION
This application claims priority from Japanese Patent Application No. 2008-064012, which was filed on Mar. 13, 2008, the disclosure of which is incorporated herein by reference in its entirety.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates generally to a recording apparatus for recording an image on a recording medium by ejecting droplets and a method for manufacturing the recording apparatus.
2. Description of Related Art
A known inkjet printer includes a plurality of inkjet heads arranged, such that the inkjet heads partially overlap one another in the conveying direction, e.g., staggered in a scanning direction perpendicular to the conveying direction. In the known inkjet printer, the inkjet heads are positioned with reference to the positions of the nozzles arranged in the overlapping regions of the inkjet heads, or, with reference to alignment marks formed in the ink ejection surfaces of the inkjet heads.
In the known inkjet printer, the nozzles formed in the inkjet heads are spaced apart from one another by a distance equal to the print resolution in the scanning direction. Therefore, the nozzles formed in overlapping regions of the inkjet heads are not arranged in a straight line extending in the conveying direction. Thus, it is difficult to position adjacent inkjet heads in the conveying direction with reference to the positions of their nozzles.
SUMMARY OF THE INVENTION
A need has arisen for a recording apparatus capable of accurately and easily positioning the recording heads.
According to an embodiment of the invention, a recording apparatus comprises a first recording head and a second recording head. The first recording head comprises a first nozzle plate. The first nozzle plate comprises a first plurality of nozzle holes and a first positioning hole configured to position the first recording head. The second recording head is adjacent to the first recording head in a first direction. The second recording head comprises a second nozzle plate. The second nozzle plate comprises a plurality of nozzle holes and a second positioning hole configured to position the second recording head. The first positioning hole and the second positioning hole are aligned in the first direction.
According to another embodiment of the invention, a recording apparatus comprises a plurality of recording heads arranged adjacent to one another in a first direction. Each of the recording heads comprises a nozzle plate. Each nozzle plate comprises a plurality of nozzle holes and at least one positioning hole configured to position the plurality of recording heads. A first positioning hole formed in a first nozzle plate of a first recording head and a second nozzle hole formed in a second nozzle plate of a second recording head adjacent to the first recording head are aligned in the first direction.
According to yet another embodiment of the invention, a recording apparatus manufacturing method comprises the steps of arranging a first recording head and a second recording head adjacent to the first recording head in a first direction. Each of the first and the second recording heads comprises a nozzle plate which comprises a plurality of nozzle holes, at least one detection hole, and at least one positioning hole configured to position the recording heads. The manufacturing method further comprises the steps of attaching the first and the second recording heads to the recording apparatus, determining the positions of a first positioning hole of the first recording head and a second positioning hole of the second recording head, detecting the positions of the first and the second positioning holes with reference to the at least one detecting hole of each of the first and the second recording head, confirming the positions of the first and the second positioning holes, and positioning the first and the second inkjet heads, such that the first and the second positioning holes are aligned in the first direction.
Other objects, features, and advantages of the invention will be apparent to persons of ordinary skill in the art in view of the foregoing detailed description of the invention and the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
For a more complete understanding of the invention, the needs satisfied thereby, and the objects, features, and advantages thereof, reference now is made to the following description taken in connection with the accompanying drawings.
FIG. 1 is a side view of an inkjet printer according to an embodiment of the invention.
FIG. 2 is a plan view of inkjet heads according to an embodiment of the invention.
FIG. 3 is a plan view of a head body according to the embodiment of FIG. 2 .
FIG. 4 is an enlarged view of a region enclosed by a dashed-line in FIG. 3 .
FIG. 5 is a cross-sectional view along line V-V in FIG. 4 .
FIG. 6A is an enlarged partial view of regions in which two of the ink jet heads overlap each other according to the embodiment of FIG. 2 .
FIG. 6B is an enlarged view of a region enclosed by a dashed-line in FIG. 6A .
FIG. 7 is an enlarged plan view of positioning holes according to the embodiment of FIG. 2 .
FIG. 8 is an enlarged partial view of nozzles holes and positioning holes according to another embodiment of FIG. 7 .
DETAILED DESCRIPTION OF EMBODIMENTS
Embodiments of the invention and their features and technical advantages may be understood by referring to FIGS. 1-8 , like numerals being used for like corresponding portions in the various drawings. References to the “right” or “left” side refer to opposite sides consistent with the orientation of the referenced figure.
Referring to FIG. 1 , an inkjet printer 101 , e.g., a color inkjet printer, may comprise a plurality of inkjet heads 1 , e.g., eight, inkjet heads 1 . Inkjet printer 101 may comprise a sheet feeding part 11 on the left side, a sheet discharging part 12 on the right side, and a sheet conveying path extending from sheet feeding part 11 to sheet discharging part 12 for conveying a sheet P, as shown in FIG. 1 .
A plurality of feed rollers, e.g., feed rollers 5 a and 5 b , may nip and convey sheet P, and may be disposed at the downstream side of sheet feeding part 11 in a sheet conveying direction. Feed rollers 5 a and 5 b may feed sheet P from sheet feeding part 11 in the sheet conveying direction, e.g., toward the right in FIG. 1 . A conveying mechanism 13 may be disposed in sheet conveying path 11 . Conveying mechanism 13 may comprise a plurality of belt rollers, e.g., belt rollers 6 and 7 ; an endless conveying belt 8 that wraps and moves around belt rollers 6 and 7 ; and a platen 15 positioned in a region surrounded by conveying belt 8 . Platen 15 may support conveying belt 8 at a position opposite to the positions of inkjet heads 1 to prevent conveying belt 8 from sagging downward. A nip roller 4 may be disposed at a position opposite belt roller 7 . Nip roller 4 may press sheet P fed from feed rollers 5 a and 5 b onto an outer circumference 8 a of conveying belt 8 .
When a conveying motor (not shown) rotates belt roller 6 , conveying belt 8 may convey sheet P from nip roller 4 to sheet discharging part 12 , and may hold sheet P with a weak adhesive force on the surface of conveying belt 8 during the sheet conveying process. The surface of conveying belt 8 may comprise a weak-adhesive, silicon resin layer.
A separating mechanism 14 may be disposed on the downstream side of conveying belt 8 in the sheet conveying direction. Separating mechanism 14 may separate sheet P from outer circumference 8 a of conveying belt 8 and may guide sheet P to sheet discharging part 12 .
Referring to FIG. 2 , inkjet heads 1 may have a substantially rectangular-parallelepiped shape, elongated in a direction, e.g., main scanning direction, perpendicular to the sheet conveying direction, e.g., the direction from the bottom to the top in FIG. 2 . A plurality of inkjet heads 1 , e.g., eight inkjet heads 1 , may be arranged, such that the inkjet heads alternately reverse orientation in the sheet conveying direction. Inkjet heads 1 may be arranged in an alternately reversed manner in the sheet conveying direction. Two adjacent inkjet heads 1 in the sheet conveying direction may comprise an inkjet head pair. A plurality of inkjet head pairs, e.g., four inkjet head pairs, may be arranged in the sheet conveying direction. Each of the plurality of inkjet head pairs may correspond to one of a plurality of colors of ink, e.g., magenta, yellow, cyan, and black. Each inkjet head 1 may eject ink droplets of its corresponding color.
Two inkjet heads 1 of each inkjet head pair may be disposed, so that the pair of inkjet heads partially overlap each other in the sheet conveying direction and are offset from each other in the main scanning direction. The length of the ejection area of an inkjet head pair in the main scanning direction may be greater than the width of sheet P. Inkjet printer 101 may be a line printer. In another embodiment, a plurality of inkjet heads 1 may be aligned linearly in the sheet conveying direction, without offset from each other in the main scanning direction.
Referring to FIGS. 1 and 2 , inkjet heads 1 may comprise head bodies 2 at their lower ends, e.g., the portion of the inkjet heads closest to the conveying belt. The lower surfaces of head bodies 2 may comprise ink ejection surfaces 2 a which are disposed opposite from outer circumference 8 a . Ink ejection surfaces 2 a may be disposed at the lower surfaces of nozzle plates 130 . Each of ink ejection surfaces 2 a may comprise a plurality of nozzle holes 108 . Nozzle holes 108 may be arranged at a pitch of 600 dpi in the main scanning direction. When the sheet P conveyed by conveying belt 8 passes below the plurality of head bodies 2 , ink droplets of various colors may be ejected from ink ejection surfaces 2 a onto a top surface, e.g., print surface, of sheet P. In this way, a desired color image may be formed on the print surface of sheet P.
Referring to FIG. 3 , in each head body 2 , a plurality of actuator units 21 , e.g., four actuator units 21 , may be coupled to an upper surface 9 a of a channel unit 9 . Referring to FIG. 4 , each channel unit 9 may comprise ink channels with pressure chambers 110 and the like formed therein. Each actuator unit 21 may comprise a plurality of actuators, and each of the plurality of actuators may correspond to one or more of a plurality of pressure chambers 110 . Each actuator may be driven by a driver IC (not shown) and selectively may apply ejection energy to the ink in the corresponding pressure chamber.
Each channel unit 9 may have a substantially rectangular-parallelepiped shape. Upper surface 9 a of channel unit 9 may comprise a plurality of ink supply ports 105 b corresponding to ink discharge channels (not shown) of a reservoir unit. Referring to FIGS. 3 and 4 , channel unit 9 may comprise manifold channels 105 , and manifold channels 105 may communicate with ink supply ports 105 b and sub-manifold channels 105 a , which branch off from the manifold channels 105 . Ink ejection surface 2 a may comprise a plurality of nozzle holes 108 which are arranged in a matrix and may be disposed at the lower surface of channel unit 9 . A plurality of pressure chambers 110 may be arranged in a matrix in a surface of channel unit 9 , to which actuator units 21 are coupled.
A plurality of rows of pressure chambers 110 , e.g., sixteen rows, may be arranged in the longitudinal direction of channel unit 9 and spaced equal distances apart from one another, and each of the plurality of rows may be arranged parallel to one another in the main scanning direction. Actuator units 21 may have a substantially trapezoidal shape. The number of pressure chambers 110 in each pressure chamber row gradually may decrease from the longer-side end to the shorter-side end of actuator units 21 . Nozzle holes 108 also may be arranged in similar manner.
Referring to FIG. 5 , channel unit 9 may be comprise a plurality of plates, e.g., nine plates 122 to 130 , made of metal, e.g., stainless steel. Each of plates 122 to 130 may be a rectangular, flat plate elongated in the main scanning direction.
Through holes may be formed in plates 122 to 130 . Through holes may be connected by aligning and stacking plates 122 to 130 . Consequently, manifold channels 105 , sub-manifold channels 105 a , and multiple individual ink channels 132 extending from the outlets of sub-manifold channels 105 a through pressure chambers 110 to nozzle holes 108 may be formed in channel unit 9 . The lower surface of nozzle plate 130 may comprise nozzle holes 108 and may function as ink ejection surface 2 a.
Ink supplied from the reservoir unit through ink supply ports 105 b to channel unit 9 may flow from manifold channels 105 to sub-manifold channels 105 a . The ink in sub-manifold channels 105 a may flow in individual ink channels 132 . The ink may pass through apertures 112 which may function as throttles and pressure chambers 110 , before reaching nozzle holes 108 .
Referring to FIGS. 2 , 6 A and 6 B, each nozzle plate 130 may comprise nozzle holes 108 and a plurality of positioning holes 109 , e.g., four positioning holes 109 . Positioning holes 109 may have the same shape as nozzle holes 108 .
As shown in FIGS. 2 and 6A , two of the plurality of positioning holes 109 may be disposed near two edges of nozzle plate 130 in the sheet conveying direction. As shown in FIG. 6B , the two of the plurality of positioning holes 109 also may be disposed at the midpoint, in the main scanning direction, between two particular nozzle holes 108 . Two particular nozzle holes 108 may be formed in the overlapping regions of two nozzle plates 130 , adjacent to each other in the sheet conveying direction. Each of the two particular nozzle holes 108 may be one of the plurality of nozzle holes in its corresponding nozzle plate 130 and may be the nozzle hole disposed closest to the edge of its corresponding nozzle plate 130 in the main scanning direction. The other two positioning holes 109 may be arranged point-symmetrically to the aforementioned positioning holes 109 with respect to the center of the nozzle plate 130 .
Each nozzle plate 130 may comprise positioning holes 109 arranged in a plurality of pairs, e.g., two pairs. The pairs of positioning holes 109 may be disposed point-symmetrically to each other with respect to the center of nozzle plate 130 . One of the two pairs of positioning holes 109 , e.g., the pair formed in the overlapping region, may be disposed along a straight line X, extending generally in the sheet conveying direction. In the nozzle plates 130 of two inkjet heads 1 adjacent to each other in the sheet conveying direction, positioning holes 109 formed in one nozzle plate 130 and positioning holes 109 formed in another nozzle plate 130 may be aligned along the straight line X.
Nozzle holes 108 formed in one inkjet head pair may be arranged at a pitch of 600 dpi in the main scanning direction by aligning the positioning holes 109 along the straight line X. A configuration in which nozzle holes 108 are arranged at equal distances apart in the main scanning direction may be provided even when inkjet heads 1 are arranged, such that the inkjet heads alternately reverse orientation. Therefore, the center of each nozzle plate 130 also may be the center of nozzle holes 108 formed in each inkjet head 1 . In various shapes of nozzle plates 130 , positioning holes 109 may be formed with respect to the center of nozzle holes 108 which are formed in each inkjet head 1 . An inkjet head pair with a predetermined resolution in the main scanning direction may be provided by aligning positioning holes 109 in two nozzle plates 130 along the straight line X.
Nozzle holes 108 may be arranged to conform to the trapezoidal shape of actuator units 21 . As shown in FIG. 3 , the plurality of actuator units 21 , e.g., four actuator units 21 , may be arranged in a staggered manner in the longitudinal direction of channel unit 9 . Moreover, the center of nozzle holes 108 may coincide with the center of actuator units 21 .
Referring to FIG. 7 , a plurality of detection holes 109 a , e.g., four detection holes 109 a , with the same shape as nozzle holes 108 may be formed in a circle C centered at positioning hole 109 in nozzle plate 130 . The plurality of detection holes 109 a may be evenly spaced apart from one another in circle C. Thus, positioning holes 109 may be detected readily with reference to detection holes 109 a.
Nozzle holes 108 , positioning holes 109 , and detection holes 109 a may be formed simultaneously by a punching member of a processing machine in the fabrication process of nozzle plates 130 . In the fabrication process, the relative positions of nozzle holes 108 , positioning holes 109 , and detection holes 109 a may be maintained precisely.
Inkjet heads 1 may be mounted to inkjet printer 101 during an assembling process of inkjet printer 101 . First, a plurality of inkjet heads 1 , e.g., eight inkjet heads 1 , may be attached temporarily to inkjet printer 101 . Second, a high-magnification camera may determine the overlapping regions of ink ejection surfaces 2 a , e.g., nozzle plates 130 , of inkjet heads 1 adjacent to one another in the sheet conveying direction. Third, with reference to detection holes 109 a , the positions of positioning holes 109 near the edges of ink ejection surfaces 2 a which are adjacent to one another in the sheet conveying direction may be confirmed. Subsequently, inkjet heads 1 may be arranged, such that positioning holes 109 of adjacent ink ejection surfaces 2 a are disposed along the same straight line X extending in the sheet conveying direction. By aligning positioning holes 109 along the same straight line X, inkjet heads 1 may be accurately and readily positioned.
Because the plurality of positioning holes 109 are arranged point-symmetrically with respect to the center of ink ejection surface 2 a , the positional relationship of the plurality of positioning holes 109 may not change even when one or more of the plurality of inkjet heads 1 are mounted to inkjet head 1 in a reverse orientation. Thus, despite various mounting orientations, inkjet head 1 may use one type of nozzle plates 130 . Accordingly, the cost of producing inkjet heads 1 for various mounting orientations may be reduced.
Two positioning holes 109 may be disposed near both edges in the width direction of nozzle plate 130 and at the midpoint, in the main scanning direction, between the particular nozzle holes 108 closest to the end edges, in the main scanning direction, of the nozzle plates 130 adjacent to each other in the sheet conveying direction. Accordingly, adjacent inkjet heads 1 may be positioned accurately with respect to one another in the sheet conveying direction by aligning the plurality of positioning holes 109 .
Referring to FIG. 8 , in nozzle plates 130 of two inkjet heads 1 adjacent to each other in the sheet conveying direction, a positioning hole 109 formed in one nozzle plate 130 and a particular nozzle hole 108 formed in the other nozzle plate 130 may be aligned along a straight line X′ extending in the sheet conveying direction.
While the invention has been described in connection with various exemplary structures and illustrative embodiments, it will be understood by those skilled in the art that other variations and modifications of the structures and embodiments described above may be made without departing from the scope of the invention. Other structures and embodiments will be apparent to those skilled in the art from a consideration of the specification or practice of the invention disclosed herein. It is intended that the specification and the described examples are illustrative with the scope of the invention being defined by the following claims. | A recording apparatus includes a first recording head. The first recording head includes a first nozzle plate. The first nozzle plate includes a first group of nozzle holes and a first positioning hole configured to position the first recording head. A second recording head is adjacent to the first recording head in a first direction. The second recording head includes a second nozzle plate. The second nozzle plate includes a second plurality of nozzle holes and a second positioning hole configured to position the second recording head. The first positioning hole and the second positioning hole are aligned in a straight line extending in the first direction. | 1 |
[0001] This invention was made with Government support under contract number F30602-03-C-2005 awarded by the U.S. Air Force. The government has certain rights in this invention.
BACKGROUND
[0002] 1. Field of the Invention
[0003] The invention is related to controlling an air vehicle after landing and during rollout to wheel stop and more particularly for controlling an air vehicle for an autonomous air vehicle rollout.
[0004] 2. Related Art
[0005] Autonomous re-entry and unmanned autonomous vehicles need a high-speed, touchdown and rollout guidance and control system for fault tolerant ground operation and control. A re-entry vehicle or an Unpiloted Air Vehicle (UAV, must transition from the airborne phase to an autonomous landing on a standard paved runway.
[0006] During the autonomous landing phase, there are considerable uncertainties, including runway friction, tire effectiveness, landing gear damping and stiffness, braking effectiveness and asymmetries, aerodynamic uncertainties and the like, which a rollout guidance and control system must compensate for to maintain the vehicle within the confine of the runway. The guidance and control system has to provide stability and performance even when all the uncertainties are included in a worst-case alignment.
[0007] The rollout guidance and control system has to be fault-tolerant and assure safe rollout even when nosewheel steering or braking system components fail.
[0008] Accordingly, there is a need to provide an autonomous rollout guidance and control system that can be reconfigured in real time and provide for fault tolerant ground.
SUMMARY
[0009] The present disclosure provides a solution for autonomously controlling an air vehicle during rollout. The invention may include a combination of guidance, navigation, and control subsystems and a plurality of effectors. The combination of subsystems uses logic to process data from the various effectors combined with navigational aids and guidance commands to handle failed sensors and effectors. The logic allows control of the various effectors in a coordinated manner to provide an autonomous air vehicle rollout. Embodiments of the disclosure will increase safety and performance margins and eliminate the need for expensive systems required to provide human intervention capability.
[0010] Unlike some systems currently available that require human intervention (either on-board or remotely) to keep the vehicle within runway limits, the present disclosure uses an autonomous reconfigurable fault tolerant guidance, navigation, and control system to control rollout. For example, the system of the present disclosure uses multiple effectors, such as the nosewheel, rudder, aileron, speed-brake, flap, left and right wheel brakes to keep a re-entry air vehicle or a UAV within runway bounds after a high-speed landing. Since all coefficients can be modified and filters re-initialized autonomously in real time compensation is possible for a given failure scenario.
[0011] This brief summary has been provided so that the nature of the invention may be understood quickly. A more complete understanding of the disclosure may be obtained by reference to the following detailed description of embodiments thereof in connection with the attached drawings
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] The foregoing features and other features of the present disclosure will now be described with reference to the drawings. In the drawings, the same components have the same reference numerals. The illustrated embodiment is intended to illustrate, but not to limit the invention. The drawings include the following Figures:
[0013] FIG. 1 is a simplified illustration of a representative air vehicle showing a general configuration for a high-speed rollout control of the air vehicle in accordance with an embodiment;
[0014] FIG. 2A is an architectural block diagram of a Rollout Control System (ROS) in accordance with an embodiment;
[0015] FIG. 2B is a flow diagram showing major functional/processing blocks of the RCS of FIG. MA, in accordance with an embodiment; and
[0016] FIGS. 3A , 3 B and 3 C graphically illustrate the simulated performance of rollout control system with a brake rotor failure during braking, in accordance with an embodiment.
DETAILED DESCRIPTION
[0017] In one embodiment, air vehicle 100 includes a conventional landing system, including main landing gear (MLG) 104 , nose landing gear 106 and aero surfaces 108 , such as ailerons, rudders, and the like. The MLG 104 and nose landing gear 106 include gears, brakes, wheels and associated hardware as is well known in the art. In one embodiment, MLG 104 includes a left wheel and a right wheel with brakes, but may include any number or combination of wheels used for landing. Nose landing gear 106 includes nose wheel 114 with steering capability. Collectively, MLG 104 , nose landing gear 106 , and aero surfaces 108 are components of control effectors 206 ( FIG. 2A ).
[0018] Generally, air vehicle 100 also includes a processing means 110 , including a computer or equivalent processor and a sensing system 112 (described below). Processing means 110 may be capable of responding to operational signals or electrical pulses from various sensors. In one embodiment, processing means 110 includes a Flight Management Computer IFMC) 110 or the equivalent, the functions of which are well known in the art.
[0019] FIG. 2A is an architectural block diagram of RCS 200 in accordance with an embodiment of the present disclosure. The RCS includes sensing system 112 , rollout Guidance Navigation Control (GNC) 204 , and control effectors 206 , operationally controlled by processing means 110 .
[0020] Sensing system 112 includes navigation/control sensing unit 202 , which includes, in one embodiment, an Inertial Measurement Unit (IMU).
[0021] In one embodiment rollout GNC 204 may include rollout controller 210 and is operationally controlled by processing means 110 .
[0022] In operation, landing air vehicle 100 has to stay close to the runway centerline and stop within the runway length, and width, while subject to the vehicle performance limitations. In addition, air vehicle 100 has to perform tracking and stopping tasks in the presence of head, tail, and crosswinds with nominal and failed subsystems In one embodiment, processing means 110 uses information provided by IMU 202 to monitor the distance between the position of air vehicle 100 and a side edge of a landing runway and an end of the length of the landing runway. Processing means 110 issues commands such that air vehicle 100 may be made to track the centerline of the landing runway.
[0023] In operation, once air vehicle 100 is on the ground, Rollout GNC 204 uses IMU 202 to compute the length of remaining runway and distance from runway edge. IMU 202 also supplies the position of air vehicle relative to the center of the runway. Data from calculations performed by Rollout GNC 204 using processing means 110 are used to automatically adjust the speed and downrange and cross-range demands of air vehicle 100 to safely control air vehicle 100 .
[0024] For example, if data by IMU 202 indicate that air vehicle 100 is off of the centerline, Rollout GNC software 204 calculates corrective commands to rollout controller 210 to adjust aero surfaces 108 , nose wheel 106 , and left and right brakes 104 to steer air vehicle 100 back to the correct position.
[0025] In another example, if data by IMU 202 indicate that air vehicle 100 is approaching the end the runway, Rollout GNC 204 calculates a deceleration profile to issue commands to rollout controller 210 to adjust the braking levels of MLG 104 to brake air vehicle 100 to stop before the end of the runway is reached.
[0026] Rollout GNC 204 uses control effectors 206 of air vehicle 100 in an integrated fashion to avoid adverse effects that may be realized if control effectors 206 were not used in an integrated fashion. For example, the rudder controls yaw, but produces significant adverse roll. The symmetric brakes produce drag to slow air vehicle 100 , but could produce significant asymmetric torques, which result in severe yawing. Nosewheel 106 provides yawing, but with its small deflections, it could remain within the hardware non-linearities, which produce limit cycles. A coordinated scheme as described in this invention allows for maximum effectiveness realized from each control effector 206 , while not countering the effect or the effort realized of each other effector.
[0027] FIG. 2B is a block diagram 220 showing major functional/processing blocks and details of RCS 200 in accordance with an embodiment of the present disclosure.
[0028] Having already described the overall operation of RCS 200 , the remaining description is concentrated on rollout GNC 204 .
[0029] Referring now to FIGS. 1 , 2 A and 2 B, processing means 110 hosts rollout GNC 204 . Rollout GNC 204 communicates via hardware interface 208 with control effectors 206 .
[0030] Rollout GNC 204 includes rollout control 210 , symmetric braking control 212 , navigation 214 , and guidance 216 .
[0031] Inputs to rollout control 210 may include the vehicle's roll angular rate, roll angle, and yaw angular rate as sensed by onboard IMU 202 . Another set of inputs may include failure indicators, such as a nosewheel steering fall indicator and a brake fail indicator, notifying GNC 204 of failures in the corresponding systems.
[0032] Yet another input command is yaw rate command as computed by guidance 216 to track runway centerline as a function of the vehicle's lateral position and side velocity.
[0033] Still another input command is the symmetric braking command, which is used to bring vehicle 100 to a stop.
[0034] In one embodiment, the sensed inputs described above are filtered through standard 1st, 2nd, and/or notch filters to remove sensor noise, vehicle structural vibration and gear noise. The sensed inputs are combined with the yaw rate command via typical PID controllers, with PID gains scaled as a function of dynamic pressure (or airspeed or groundspeed), and IC distributed as commands to the various control effectors 206 (aero surfaces 108 , nosewheel steering 106 , and differential braking 104 ). The PID controller gains are re-scaled upon notification of nosewheel steering failure or brake failure via the failure indicators. The commands to the control effectors are limited to the specific effectors' deflection limit and rate limit
[0035] The differential braking command is combined with the symmetric braking command via the brake control allocation module 218 to form a Left and Right brake commands going to the brake actuators.
[0036] Symmetric braking module 212 includes a symmetrical brake logic (not shown) which ensures that the predetermined brake command is sufficient to stop the vehicle within runway bounds by continually calculating the distance between the vehicle's present position and the end of the runway. If an unpredicted high-energy state touchdown or rollout occurs and the pre-set nominal brake command profile is not sufficient to stop the vehicle by the end of the runway then the logic adjusts the command level such that the vehicle stops within runway limitations.
[0037] Brake control allocation logic block 218 receives command inputs from symmetric braking 212 and rollout control 210 , which includes differential brake control algorithms. Brake control allocation logic block 218 then integrates, commands and allocates these commands to the individual brake assemblies. In one embodiment, the differential brake command is distributed at an optimal 50/50 ratio. If, however, there is insufficient symmetrical brake command present to cover a 50% differential subtraction then the remainder is added to the opposite side. For example, if no symmetrical brake command is present then all the differential command is added to one brake assembly since no differential command can be subtracted from the opposite side. The logic prioritizes commands based on the severity of the rollout scenario. For example, if the vehicle is close to the runway's end threshold then priority is given to the symmetrical brake commands to stop the vehicle safely on the runway. However, at high-speeds priority is given to differential commands to keep the vehicle on track with the runway centerline.
[0038] Embodiments of the logic provide a system that reconfigures priorities if a fail should occur with the control effectors. For example, if the system detects a nosewheel steering failure the control allocator reconfigures and gives priority to differential braking to makeup for the loss in lateral control authority.
[0039] FIGS. 3A , 3 B and 3 C illustrate of the simulated performance of rollout control system 200 of unmanned air vehicle 100 , which suffered a brake rotor failure following brake initiation. The invention safely reconfigured the rollout control system 200 and brought air vehicle 100 to a safe stop on the runway and within inches of the runway centerline.
[0040] Graph 302 shows air vehicle's 100 displacement relative to a centerline along a runway. Graphs 304 and 306 show air vehicle's 100 right and left brake commands respectively, along the runway. Graph 308 shows nosewheel command along the runway. Due to uneven brake performance, more right wheel and right nosewheel command are required to counter the asymmetry.
[0041] Brakes are initialized at 7000 feet. A right brake rotor fails at the 9000 feet point of the runway (1 of 3 rotors fails). Once the failure is detected, a corresponding left brake rotor is disabled to maintain brake symmetry, brake gain and nosewheel steering gain are adjusted in real time to this new configuration.
[0042] Air vehicle 100 comes to a stop at 10200 feet point of the runway and only inches from the centerline.
[0043] Although the present disclosure has been described with reference to specific embodiments, these embodiments are illustrative only and are not limiting. Many other applications and embodiments of the present disclosure will be apparent in light of this disclosure and the following claims. | A real time reconfigurable, fully integrated, fault tolerant guidance and control system to act in a coordinated fashion to bring a re-entry air vehicle or a UAV to a stop, while keeping it within runway bounds after a high-speed landing. | 6 |
BACKGROUND OF THE INVENTION
The invention relates to a method of manufacturing an optoelectronic semiconductor device with a semiconductor body, whereby a semiconductor layer structure is provided on a semiconductor substrate by means of a non-selective growing process, an etching process and a selective growing process, a first portion of this structure comprising a comparatively thin active layer and a second portion situated adjacent and against the first portion comprising a comparatively thin radiation-guiding layer, while said semiconductor layer structure further comprises a cladding layer situated over the thin layers.
Such a method is highly suitable inter alia for manufacturing diode lasers comprising a waveguide. The waveguide then comprises, for example, a non-absorbing minor region or an extension of the resonance cavity which is provided, for example, with a grating. Other devices having an active element such as a diode laser, a laser amplifier, or a photodiode integrated with a waveguide may also be advantageously manufactured by such a method. In that case, components such as lasers, amplifiers, detectors, waveguides, modulators, switches, etc, may be integrated.
Such a method is known from European Patent Application 90902703.9 published under no. 0 411 145 on Jun. 6, 1991. It is described therein how in this manner a DFB (=Distributed Feed Back) diode laser with an active layer and an optical modulator with a radiation-guiding layer are integrated on a substrate. A 0.15 μm thick InGaAsP (λ=1.55 μm) active layer 4 and a 0.5 μm thick InP cladding layer 5 are provided on an InP substrate 1 (see column 6 and FIGS. 9 to 13 of EP 0 411 145) by means of a non-selective growing process. These layers are locally removed by etching outside a first portion of the layer structure. After this, a second portion of the layer structure situated adjacent and against the first portion is provided here by a selective growing process. The second portion comprises an InGaAsP (λ=1.4 μm) radiation-guiding, --and here also radiation-absorbing--layer 6 and an InP cladding layer 7, which adjoin to the active layer 4 and the cladding layer 5, respectively, in the first portion substantially contiguously.
A disadvantage of the known method is that in this method unevennesses and/or openings can arise in the cladding layer near the surface of and at the area of the transition between the two portions of the layer structure. Such defects cause problems in the implementation of various processes usual in manufacture, such as photolithographic, metallization, deposition or etching processes.
SUMMARY OF THE INVENTION
The invention has for its object to provide a method of the kind mentioned in the opening paragraph whereby optoelectronic semiconductor devices can be obtained whose surfaces are at least substantially plane and free from defects. Further manufacturing steps can be carried out accurately and with a high yield as a result of this. The devices thus manufactured accordingly have a narrow spread in their properties.
According to the invention, a method of the kind mentioned in the opening paragraph is for this purpose characterized in that one of the thin layers and a small portion of the cladding layer are provided in a first non-selective growing process, the layers provided are locally removed in the etching process and the other thin layer and again a small portion of the cladding layer are provided in this area in the selective growing process, and subsequently in a second non-selective growing process the major portion of the cladding layer is provided. The invention is based inter alia on the recognition that an imperfect connection between two layer structures is more likely to arise in a selective growing process for one layer structure next to an existing layer structure in proportion as these structures are thicker. This is connected inter alia with the fact that abnormally high or low growth rates occur in a selective growing process near the transition between the two layer structures. In proportion as the thickness of the layer structure to be grown selectively is greater, accordingly, the absolute value of the difference in thickness in this layer structure close to and remote from the transition increases. This great absolute difference in layer thickness results in defects and unevennesses (openings or steps) in the surfaces of the layer structures near the transition between them. The said differences in growth rate have different causes--partly depending on the growing technique--such as the lateral limitation of the growing layer structure by a crystal phase which is not perpendicular to the thickness direction. Now if one of the thin layers and only a small portion of the cladding layer are grown each time both in a first non-selective and in the selective growing process, it is achieved owing to the comparatively small total thickness of the layers grown up to that point that these layers merge well into one another seen in absolute terms and the surface near the transition is comparatively plane and free from defects. Since the growth is then continued with a second non-selective growing process, in which the major portion of the cladding layer is provided, the plane and defect-free surface is conserved. In fact, the comparatively small unevennesses in the surface near the transition are even reduced in the latter process. Such a planarizing effect occurs especially when LPE (=Liquid Phase Epitaxy) is used for this process, but also when MOVPE (=Metal Organic Vapour Phase Epitaxy) is used, such an improvement in planeness will occur. Thanks to the method according to the invention, furthermore, it is achieved that the active layer and the radiation-guiding layer are no longer exposed to air or water after being grown, when the structure is removed from the growing reactor, because they are covered then with a (small) portion of the cladding layer. Such an exposure may result in serious degradation of the optoelectronic properties, which is obviously highly undesirable. It is noted that an intermediate removal from the reactor is necessary for providing a mask and for etching away part of the layer structure. A very important advantage of the method according to the invention, finally, is that a very good optical connection is obtained thereby between the active and the radiation-guiding layers.
In a first embodiment of a method according to the invention, at most one quarter of the cladding layer is provided in the first non-selective and the selective growing process, and at least three quarters of the cladding layer are provided in the second non-selective growing process. In the known method, a cladding layer of approximately 0.5 μm is provided. In practice, a thickness of approximately 1 μm is often used. One quarter of the cladding layer accordingly, corresponds to 0.12 to 0.25 μm. An active or radiation-guiding layer normally has a thickness of approximately 0.15 μm. The package grown in the first growing processes according to the invention thus preferably has a thickness of approximately 0.27 to 0.40 μm. The remaining portion of the cladding layer then is substantially thicker, i.e. approximately 0.38 to 0.75 μm thick, whereby major improvements are already obtained. Preferably, at most one tenth of the cladding layer is provided in the first growing processes, corresponding to a thickness of approximately 0.05 to 0.1 μm. On the one hand, this thickness is still amply sufficient for an effective screening of the layer below the cladding layer, and on the other hand the maximum advantages of the invention are substantially obtained thereby. In fact, the thickness yet to be grown is determined by the thickness of the active or radiation-guiding layer in the case of even smaller ratios. In the first non-selective and in the selective growing process, other comparatively thin layers, such as thin etching stopper layers and/or further radiation-guiding layers, may be provided besides an active or radiation-guiding layer without detracting from the advantages of the method according to the invention. Preferably, according to the invention, the thickness of the total layer package provided in the selective growing process is so chosen that this package is coplanar with the layer package provided in the first non-selective growing process. In practice this will often be done in that equal thicknesses are chosen for the various packages. When the thickness desired for the package to be selectively provided is so great that this is no longer possible, a depression may be etched in the area where the latter package is to be provided before this package is provided.
In an important preferred embodiment of the method according to the invention, a strip-shaped mesa is formed in the semiconductor layer structure by means of etching after the second non-selective growing process, the longitudinal direction of this mesa being substantially perpendicular to the transition between the first and the second portion of the semiconductor layer structure, while this mesa extends in both portions of the semiconductor layer structure and comprises a portion of the cladding layer. Such mesa-shaped strips are used, for example, in the manufacture of diode lasers or waveguides of the so-called ridge waveguide type or of the buried hetero type. The method according to the invention has particularly great advantages in the manufacture of devices of the former type. This is because often a mesa is etched into the cladding layer in that case, whereby a major portion of this layer is removed and a comparatively small portion is kept intact. Thanks to the method according to the invention, the thickness of this small portion can be set accurately and with a high homogeneity over a large number of devices on one substrate. An etching stopper layer is often used for etching of a mesa. An important advantage of the method according to the invention is that, when such a layer is provided in (at the start of) the second non-selective growing process, such a layer contains no interruption at the area of the transition between the active and the radiation-guiding layer. In the known method, such an etching stopper layer must be provided in two portions, so that an accurate transition between the two portions is not possible and the layer cannot act (satisfactorily) as an etching stopper at the area of the said transition. Major advantages such as a plane structure free from defects and a good optical connection between the active and radiation-guiding layers, however, are obtained in the manufacture of devices of both types.
In a further embodiment, a further layer structure, preferably a current-blocking layer structure, is provided on either side of the mesa-shaped structure in a further selective growing process, and at least a contact layer is provided in the second non-selective growing process or in a further non-selective growing process. In this manner, for example, a diode laser is manufactured with a SIPBH (=Semi-Insulating Planar Buried Hetero) or a DCPBH (=Double Channel Planar Buried Hetero) structure. In the latter structure, the further non-selective growing process often is the final part of the second non-selective growing process, wherein not only a contact layer but also a portion of the cladding layer is provided.
In a major embodiment of a method according to the invention, the cladding layer and the contact layer provided thereon are not purposely doped while being provided. This has the very important advantage that the radiation losses in the radiation-guiding layer are low, for example, 1 dB/cm. A Zn-doped cladding layer results in losses of approximately 10 dB/cm. According to the invention, a dopant is locally provided in the contact layer and in the cladding layer wherever this is necessary. A Zn dopant is especially suitable for this. In that case, an n-type substrate is used with possibly an overlying n-type epitaxial layer on which the active and radiation-guiding layers are provided. An n-type doped layer or substrate substantially does not contribute to the said loss of 1 dB/cm. If so desired, the substrate and an epitaxial layer provided thereon may also be doped only locally.
A very favorable embodiment of a method according to the invention is characterized in that in the second portion of the semiconductor layer structure a strip-shaped mesa is formed in which a dopant is provided over half the width thereof in the cladding layer and the contact layer and which, seen from above, branches out at either end into two further strip-shaped mesas, one of the two further strip-shaped mesas which merge into the non-doped portion of the strip-shaped mesa being formed in the first portion of the layer structure and the remaining mesas in the second portion thereof, while a riopant is provided in the cladding layer and the contact layer of the one further mesa. A device is obtained by such a method which comprises a so-called TIR (=Total Internal Reflection) switch and an amplifier (integral therewith). This device is thus obtained in a simple manner and with a high yield and has very favourable properties, such as very low-loss waveguides, thanks to the local doping of the cladding layer and the contact layer.
Preferably, in a method according to the invention, n-type InP is chosen as the material of the substrate and the further cladding layer, InGaAsP (λ=1.5 μm) for the material of the active layer, InGaAsP (λ=1.3 μm) for the material of the radiation-guiding layer, p-type InP for the material of the cladding layer, p-type InGaAs(P) for the material of a contact layer, and n-type InP and p-type InP are chosen for the material of a current-blocking layer structure situated adjacent the mesa-shaped strip, Zn is used as the p-type dopant, and the semiconductor body is provided with two mirror surfaces which are mutually parallel, which extend perpendicular to the longitudinal direction of the mesa-shaped strip, and between which the first and the second portion of the layer structure are present, by means of cleaving. Devices are obtained in this manner which comprise, for example, a diode laser or laser amplifier integrated with a waveguide and which are suitable for use in optoelectronic applications such as optical glass fibre communication systems.
BRIEF DESCRIPTION OF THE INVENTION
The invention will now be described with reference to several embodiments and the drawing, in which
FIG. 1 diagrammatically shows a semiconductor diode laser, partly in perspective view and partly in cross-section, manufactured by a first embodiment of a method according to the invention,
FIG. 2 diagrammatically shows the semiconductor diode laser of FIG. 1 in cross-section taken on the line II--II,
FIGS. 3 to 8 show the semiconductor diode laser of FIG. 1 in consecutive stages of manufacture by a first embodiment of a method according to the invention, FIGS. 3 to 6 being cross-sections taken on the line II--II and FIGS. 7 and 8 being cross-sections taken on the line VII--VII in FIG. 1,
FIG. 9 diagrammatically shows a semiconductor diode laser amplifier integrated with a switch in perspective view, manufactured by means of a second embodiment of a method according to the invention,
FIGS. 10 and 11 diagrammatically show the device of FIG. 9 in cross-section taken on the lines X--X and XI--XI, and
FIGS. 12 to 17 show the device of FIG. 9 in consecutive stages of manufacture by a second embodiment of a method according to the invention, and in cross-section taken on the line X--X in FIG. 9.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 diagrammatically shows a semiconductor diode laser, partly in perspective view and partly in cross-section, manufactured by a first embodiment of a method according to the invention. A diagrammatic cross-section of the semiconductor diode laser of FIG. 1 taken on the line II--II is shown in FIG. 2. The semiconductor diode laser (see FIG. 1) comprises a semiconductor body 100 with a substrate 1 of a first, here the n-conductivity type provided with a metal layer 3 and a connection conductor 8, while a grating 2 is present locally within a portion B of a layer structure. The layer structure comprises inter alia the following regions: on the one hand a strip-shaped mesa 9 and on the other hand two regions 90 situated outside grooves 10, which regions are all subdivided into three sections at an upper side on which connection conductors 5, 6 and 7 are arranged. The layer structure here comprises a comparatively thin active layer 13 which is present within a portion A only, and an also comparatively thin radiation-guiding layer 21 which is present only within the portion B of the layer structure adjoining the first portion A. Furthermore, there is a first cladding layer 30, here of the p-conductivity type, which extends over the comparatively thin layers 13, 21, and on top of that, divided into three sections, a contact layer 34, here also of the p-conductivity type, and a metal layer 4. The layer structure further comprises a further radiation-guiding layer 11, a second cladding layer 31, here of the p-conductivity type, a third cladding layer 32, here of the n-conductivity type, a fourth cladding layer 33, here of the p-conductivity type and further cladding layers 12, 1, here of the n-conductivity type. The diode laser can be operated and continuously attuned as to wavelength by means of the connection conductors 5, 6, 7, 8. Between the layers 12 and 30 there is in the layer structure a pn junction which, given a sufficient current strength in the forward direction at least at the area of portion A, is capable of generating coherent electromagnetic radiation in the active layer 13. The cladding layers 1, 12, 30 each have a smaller refractive index for the laser radiation generated than does the active layer 13, and have a wider bandgap than the active layer 13. The radiation generated can propagate from the active layer 13 in the radiation-guiding layers 11, 21 which have a refractive index and bandgap which lie between those of the active layer 13 and the cladding layers 1, 12, 30, because the thickness of portion 12 of the further cladding layer is such that the further radiation-guiding layer 11 lies within the amplification profile of the active layer 13 and the radiation-guiding layer 21. Within the mesa 9, the active layer 13 and the radiation-guiding layers 11 and 21 form a strip-shaped resonance cavity which is bounded on two sides by two flanks of the mesa-shaped portion, and on two other sides by two end faces 50 and 51 which are substantially perpendicular to the active layer 13, one of these (the end face 51) being provided with an anti-reflection coating 55 which serves inter alia for preventing as much as possible that competition arises between the Bragg reflection at the grating 2 and a reflection at the mirror surface 5 I. The radiation emerging at the end face 50 is available for use. This radiation is guided, for example, into a glass fibre in the case of optical glass fibre communication. The laser according to the present example is of the DCPBH type mentioned above and comprises a current-blocking layer structure in the grooves 10 outside the mesa 9, which structure comprises a second cladding layer 31, here of the p-conductivity type, a third cladding layer 32, here of the n-conductivity type, and a fourth cladding layer 33, here of the p-conductivity type, the layers 31 and 33 being connected to and merging into the first cladding layer 30 near the edge of the mesa 9. In this example, the substrate 1, the further cladding layer 1, 12, and the current-blocking layer 32 comprise n-InP. The cladding layer 30 and the current-blocking layers 31 and 33 comprise p-InP. Note that in the InP/InGaAsP material system of this embodiment, the substrate 1, comprising InP, also functions as a cladding layer. The other layers comprise indium-gallium-arsenic-phosphorus (In x Ga 1-x As y P 1-y ). The values of (x, y) for the radiation-guiding layers 11 and 21 and the contact layer 34 are: x=0.72 and y=0.60, and for the active layer 13: x=0.57 and y=0.91. The remaining layers are not purposely doped.
The semiconductor diode laser described is manufactured as follows in a first embodiment of a method according to the invention, see FIGS. 3 to 8, in which FIGS. 3 to 6 are cross-sections taken on the line II--II in FIG. 1 and FIGS. 7 and 8 are cross-sections taken on the line VII--VII in the same Figure. The process starts with a substrate 1 of n-type InP with a thickness of approximately 360 μm, a (100) orientation and a doping concentration of, for example, 5×10 18 atoms per cm 3 . This substrate may be a single substrate, but it may alternatively be formed by an epitaxial layer grown onto a subjacent carrier body. A diffraction grating 2 is etched into this substrate 1 (see FIG. 3) with a grating constant of approximately 240 nm. For this purpose, a photoresist layer is first provided on the upper surface to a thickness of approximately 100 nm. A raster pattern is formed from this photoresist layer by means of holographic illumination with the use of the 363.8 nm line of an argon laser. This pattern is used as a mask in an etching process in which a pattern 2 of parallel grooves is etched into the upper surface of the substrate, for example, by means of a solution of hydrogen bromide (HBr) and bromine (Br 2 ) in water in a composition of H 2 O:HBr:Br 2 =60:30:1. After removal of the photoresist, an approximately 0.2 μm thick layer 11 with the composition In 0 .72 Ga 0 .28 As 0 .60 P 0 .40 which entirely fills up the grooves 2 in the substrate 1, is provided by a growing technique, in this case MOVPE (=Metal Organic Vapour Phase Epitaxy). Then an approximately 0.1 μm thick layer 12 of InP, which is not purposely doped, is grown thereon.
In a first non-selective growing process according to the invention, a comparatively thin active or radiation-guiding layer is then provided, here an approximately 0.15 μm thick active layer 13 of not purposely doped In 0 .57 Ga 0 .43 As 0 .91 P 0 .09, as well as a small portion 14 of a cladding layer to be formed, here an approximately 0.10 μm thick InP layer 14 with a doping level of 1×10 18 Zn atoms/cm 3 . After removal from the growing equipment, a masking layer 41 of silicon dioxide (SiO 2 ) is provided, for example, by sputtering. Then the layer 41 (see FIG. 4) is removed in a usual manner at the area of portion B, after which, according to the invention, the layer structure is etched away at the area of portion B, with the remaining portion of the layer 41 serving as a mask, down to the layer 12 which acts as an etching stopper. After cleaning in a usual manner, the obtained structure according to the invention is placed in the growing equipment again and (see FIG. 5) the other comparatively thin layer, here the radiation-guiding layer 21, in this case an approximately 0.15 μm thick layer 21 of not purposely doped In 0 .72 Ga 0 .28 As 0 .60 P 0 .40, and an also small portion 22 of a cladding layer to be formed, here an approximately 0.10 μm thick layer 22 of p-type InP with a doping level of l×10 18 atoms/cm 3 are locally provided in a selective growing process with the layer 41 serving as a mask. The comparatively thin layers 13, 21 and the small portions 14, 22 of a cladding layer to be formed merge comparatively well into one another, according to the invention, and result in a substantially plane surface free from defects of the portion of the layer structure grown thus far. The thicknesses of the layers 21, 22 are so chosen here that the sum of these thicknesses is equal to the sum of the thicknesses of the layers 13, 14. After the obtained structure has been taken from the growing equipment, layer 41 has been removed; and the structure has been cleaned, according to the invention, (see FIG. 6) the major portion 15 of a cladding layer 30 to be formed is provided by means of a second non-selective growing process. The portion 15 here comprises a 1 μm thick layer of p-type InP with a doping concentration of 1×10 18 atoms/cm 3 . As a result of this, according to the invention, the surface of the layer structure remains comparatively plane and free from defects after the second non-selective growing process. In this example, the portion 14, 22 of the cladding layer 30 to be formed which is provided before the second non-selective growing process amounts to 0.1/(0.1+)=9/100 of the portion 40 formed thus far of the cladding layer to be provided, which is less than 1/4 and even less than 1/10 in this case. The maximum advantages of the method according to the invention are substantially obtained thereby.
After removal from the growing equipment and cleaning, the next step in the present example (see FIG. 7) is to provide a mesa 9 by means of photoresist, photolithography, and usual etching means in the form of a strip situated between grooves 10, the longitudinal axis of this mesa being substantially perpendicular to the transition between the portions A and B of the layer structure, while this mesa extends over the two portions A and B and comprises a portion 14, 22, 15 of the cladding layer 30 and here also the active layer 13, the radiation-guiding layer 21 and a portion of a further cladding layer 12, 1, situated below the said layers, as well as in this case also the further radiation-guiding layer 11 (see also FIG. 1 ). The width of the mesa 9 is approximately 0.9 μm. After removal of the photoresist and cleaning, the structure thus obtained is returned to the growing equipment and a number of semiconductor layers is grown (see FIG. 8). First a p-type InP layer 31 is grown on either side of the mesa 9 with a doping of 8×10 17 Zn atoms per cm 3 , and on top of that an n-type current-blocking layer 32 of InP with a doping of 8×10 17 Ge atoms per cm 3 . These layers fill the grooves 10 partly or completely, but they do not grow on the mesa 9. This is connected with the fact that the growing method used here involves growing from the liquid phase, with the geometry of the structure, and with the time in which the layers are grown. The layer 31 touches the edges of layer 15 in the mesa 9. Subsequently, in a further non-selective growing process in the present example, again from the liquid phase, a p-type InP layer 33 with a thickness of, for example, 0.7 μm and a doping concentration of 1×10 18 Zn atoms per cm 3 , and a p-type contact layer 34 of the composition In 0 .72 Ga 0 .28 A 0 .60 P 0 .40, a thickness of 0.5 μm and a doping concentration of 1×10 19 Zn atoms per cm 3 are grown. Layer 33 fluently merges into the layer 15 (see also FIG. 1) above the mesa-shaped region 9. As is evident from this example, the manufacture of the portion 15, 31 of the cladding layer 30 which is provided in the second non-selective growing process can take place advantageously in several steps, whereby the second non-selective growing process in fact comprises two non-selective growing processes. In this example, the portion 14,22 of the first cladding layer 30 (comprising portion 14,22 and layers 15 and 33) which is provided before the second non-selective growing process, comprising two non-selective growing processes in this example, finally amounts to 0.1/(0.1+1+0.7)=6/100 of the first cladding layer 30, which is even less than the value of 9/100 mentioned above.
After the structure thus obtained has been taken from the growing equipment, metal layers 4 and 3 of conventional composition are provided in usual manner at the upper and lower side of the semiconductor body 100, so that electrical connections can be provided thereon. If so desired, further current-limiting measures may be taken before the metal layer 4 is provided. Thus it is possible to carry out a zinc diffusion into the surface locally above the mesa-shaped portion 9, or an implantation with H + ions may be carried out outside this portion whereby the semiconductor body (100) is given a high ohmic value at the area of this implantation. Then two grooves are etched into the upper side of the semiconductor body 100 (see FIG. 2) by photolithography and (selective) etching so that three sections are formed which can be provided with separate current conductors 5, 6 and 7. Finally, an anti-reflection coating 55 is provided on one of the lateral faces of the semiconductor body 100, for example by means of sputtering or vapour deposition. The electromagnetic radiation emerging at lateral face 50 (see FIG. 1) may be guided into a glass fibre.
FIG. 9 is a diagrammatic perspective view of a semiconductor diode laser amplifier integrated with a waveguide switch manufactured by a second embodiment of a method according to the invention. A diagrammatic cross-section of the device of FIG. 9 taken on the lines X--X and X1--X1 is given in FIG. 10 and 11, respectively. The amplifier with switch (see FIGS. 9, 10 and 11) comprises a semiconductor body 100 with a substrate 1 of a first, here the n-conductivity type, provided with a metal layer 3 and a connection conductor 8 and with a layer structure in which a laser amplifier 200 is present within a portion A and an X-shaped switch 300 is present within a portion B which lies adjacent and against portion A, both of the RW (=Ridge Waveguide) type. The layer structure comprises a strip-shaped mesa 9 in which a dopant 35, here a local Zn diffusion, was provided over half the width thereof, and which branches out at either end, seen in plan view, into two further strip-shaped mesas 9A, 9B, here forming the switch 300 and 9C, 9D, wherein one (9A) of the two further mesas 9A, 9B adjoining the non-doped portion of the mesa 9 lies in portion A and the remaining mesas 9B, 9C, 9D lie in the portion B, while a dopant 36, here a Zn diffusion, is provided in the cladding layer 30 and a contact layer 34 of the one further mesa 9A, which here forms the amplifier 200. At the areas of the Zn-doped regions 35, 36, there is a metal layer 4 provided with connection conductors 6, 7. One of the radiation beams 500, 600 entering the radiation-guiding layer 21 of the device 100 via mirror surface 51 is switched into the active layer 13 below the further mesa 9A by a switch 300, as selected, and then issues from the device 100 as a radiation beam 400. When the switch 300 is off, i.e. when no current flows through a pn junction situated between the connection conductors 7, 8, the radiation beam 600 continues below the further mesa 9C to the further mesa 9B, and the radiation beam 500 continues below the further mesa 9D to the further mesa 9A. When a current does flow through the connection conductors 7, 8 of the switch 300, the latter is on and a mirror surface is formed as it were at the area of the doped region 35, against which the entering radiation beams 500, 600 are reflected. Radiation beam 600 is then guided to the exit of the device 100, i.e. to the further mesa 9A. In the further mesa 9A, them is a laser amplifier 200 with a pn junction between connection conductors 6, 8. The selected radiation beam 500, 600, which was attenuated in the switch 300, is amplified again in the amplifier 200. The layer structure in which the amplifier 200 and switch 300 are formed here comprises a further cladding layer 12, here also a buffer layer, which in this case is of the n-conductivity type and comprises a comparatively thin active layer 13 situated between two also comparatively thin radiation-guiding layers 16, 17 and present within the portion A only, as well as a comparatively thin radiation-guiding layer 21 which is present within the portion B only of the layer structure. The layer structure further comprises a cladding layer 30 which extends over the comparatively thin layers 16, 13, 17 and 21, and on top of that a contact layer 34, here also at the areas of the doped regions 35, 36 of the p-conductivity type, and a metal layer 4 which is connected to the contact layer 34 above the doped regions 35, 36 and which is for the remaining part insulated from the layer structure by means of an insulating layer 42, here of silicon nitride. The strip-shaped mesas 9, 9A, 9B, 9C, 9D here comprise the contact layer 34 and a major portion 15 of the cladding layer 30. Preferably, the device 100 of FIG. 9 comprises a number, for example, four other mesas (not shown) which lie between the further mesas 9A, 9B and 9C, 9D and, seen in the plane of the drawing, in front of and behind the switch 300. The device 100 becomes substantially planar as a result of such other mesas. Among the advantages of this are that the mirror surfaces 50, 51 are free from defects, that the mesa 9 and the further strip-shaped mesas 9A, 9B, 9C, 9D are protected, and that the device 100 may readily be given a so-called upside-down final mounting. The mirror surfaces 50, 51 are provided with an anti-reflection coating which is not shown in the drawing.
When the device is used in an optical glass fibre communication system, a glass fibre will be present at the areas of the radiation beams 400, 500, 600, which is not shown in the drawing. In the present example, the substrate 1, the further cladding layer 12 and the current-blocking layer comprise n-type InP. The cladding layer 30 comprises InP. The other layers comprise In x Ga 1-x As y P 1-y . The values of (x, y) are for the radiation-guiding layers 16, 17 and 21 and for the contact layer 34: x=0.72 and y =0.60, and for the active layer 13: x=0.57 and y=0.91.
The semiconductor diode laser amplifier/switch described is manufactured as follows by a first embodiment of a method according to the invention. See FIGS. 12-17, which are cross-sections taken on the line X--X in FIG. 9. Manufacture starts with a substrate 1 of n-type InP with a thickness of approximately 360 μm, a (100) orientation and a doping concentration of, for example, 5×10 18 at/cm 3 . A further cladding layer 12, at the same time buffer layer, of n-type InP with a thickness of approximately 1 μm and a doping concentration of approximately 5×10 18 at/cm 3 is provided on this substrate by means of MOVPE (see FIG. 12).
According to the invention, and in a first non-selective growing process, the following semiconductor layers are grown thereon in this case: an approximately 0.04 μm thick radiation-guiding layer 16 with the composition In 0 .72 Ga 0 .28 As 0 .60 P 0 .40, an approximately 0.12 μm thick active layer 13 with the composition In 0 .57 Ga 0 .28 As 0 .60 P 0 .40, an approximately 0.04 μm thick radiation-guiding layer 17 with the composition In 0 .72 Ga 0 .28 As 0 .91 P 0 .40, together forming a comparatively thin, i.e. 0.20 μm thick layer, and an approximately 0.10 μm thick layer 14 of InP which forms a small portion of a cladding layer 30 yet to be formed. After removal from the growing equipment, a masking layer 41 of silicon dioxide (SiO 2 )) is provided, for example, by means of sputtering. Then the layer 41 (see FIG. 13) is removed in usual manner by etching the area of a portion B, after which according to the invention the layer structure is etched away at the area of portion B and with the remaining portion of the layer 41 serving as a mask down to layer 12, which acts as an etching stopper. After cleaning in a usual manner, the structure obtained according to the invention is returned to the growing equipment and the following layers are provided locally in a selective growing process with the layer 41 serving as a mask (see FIG. 14): the other comparatively thin layer, here comprising the radiation-guiding layer 21, in this case an approximately 0.20 μm thick layer 21 of not purposely doped In 0 .72 Ga 0 .28 As 0 .60 P 0 .40, and an again small portion 22 of a cladding layer to be formed, here an approximately 0.10 μm thick layer 22 of InP, alto not purposely doped. The comparatively thin layers 13, 21 and the small portions 14, 22 of a cladding layer to be formed thus merge comparatively well into one another according to the invention and result in a substantially plane surface free from defects of the portion of the layer structure grown thus far. The thicknesses of the layers 21, 22 are so chosen here that the sum of these thicknesses is equal to the sum of the thicknesses of the layers 16, 13, 17 and 14.
After the structure thus obtained has been taken from the growing equipment, layer 41 has been removed, and the structure has been cleaned, according to the invention (see FIG. 15), the major portion 15 of a cladding layer 30 to be formed is provided by means of a second non-selective growing process, as well as a contact layer 34 of In 0 .72 Ga 0 .28 As 0 .60 P 0 .40 with a thickness of approximately 0.20 μm, also undoped. The portion 15 here comprises a 1 μm thick layer of InP. As a result, according to the invention, the surface of the layer structure remains comparatively plane and free from defects after the second non-selective growing process. In this example, the portion 14, 22 of the cladding layer 30 to be provided, which was provided before the second non-selective growing process, comprises 0.1/1.1=9/100 of the portion 40 formed thus far of the envisaged cladding layer 30, which here is less than 1/4 and even less than 1/10. The maximum advantages of the method according to the invention are substantially obtained thereby.
After removal from the growing equipment and cleaning, in this example (see FIG. 16), a strip-shaped mesa 9 and connected further strip-shaped mesas 9A, 9B, 9C, 9D (see also FIG. 9) are formed by means of photoresist 43, photolithography, and usual etchants, here by means of RIE (=Reactive Ion Etching). FIG. 16 shows only the further mesas 9A and 9B. The further mesa 9A is present in portion A of the layer structure, the remaining mesas 9, 9B, 9C, 9D are present in a portion B of the layer structure, and all mesas here comprise in addition to the contact layer 34 a major portion 15 of the cladding layer 30, here an approximately 1 μm thick portion thereof. During the formation of such mesas 9, 9A, 9B, 9C, 9D, which extend over different portions A, B of a layer structure which were provided in different growing processes, the method according to the invention offers major advantages. Such mesas can be manufactured accurately and with a high yield thanks to the comparatively plane and defect-free state of the surface of the layer structure. This is also true when a (thin) etching stopper layer is used during etching, because in that case the degree of through-etching of such an etching stopper layer or the degree of underetching of the cladding layer 30 can be limited.
The portions of the active layer 13 situated between the radiation-guiding layers 16, 17 and of the radiation-guiding layer 21 situated below the mesas 9A and 9B form an active region of the amplifier 200 and a waveguide which forms part of the switch 300, respectively. The width of the mesa 9 is approximately 5 μm, the further mesas 9A, 9B, 9C, 9D are approximately 0.9 μm wide. The total length of the device is approximately 1800 μm, the length of the further mesas 9A, 9B is approximately 500 μm, that of the further mesas 9C, 9D approximately 300 μm, and that of the mesa 9 approximately 80 μm. The length of the gradual transition between the further mesas 9A, 9B, 9C, 9D and the mesa 9 accordingly is approximately (1000-80)2, i.e. approximately 460 μm. The angle within this transition is approximately 3°. The length of the doped region 35 of the switch 300 is approximately 250 μm. The spacing between the further mesas 9A, 9B and 9C, 9D is approximately 30 μm. Subsequently, (see FIG. 17), the manufacture is continued by the application of an approximately 0.3 μm thick layer 42 of silicon nitride in which locally a window is provided above the mesa 9 (not shown in FIG. 17) and above the further mesa 9A, through which a Zn diffusion is carried out whereby the doped regions 35 (not shown in FIG. 17) and 36 are formed.
After this (see FIGS. 10 and 11), a metal layer 4, here made of Pt, Ta, Pt and Au, is provided over the nitride layer 42 and given a certain pattern so as to form regions on which connection conductors 5 and 6 can be provided. Finally, an anti-reflection coating is provided on the mirror surfaces 50, 51 of the semiconductor body 100, for example by means of sputtering or vapour deposition.
The Figures are diagrammatic and not drawn to scale, the dimensions in the thickness direction being particularly exaggerated for the sake of clarity. Corresponding parts are generally given the same reference numerals in the various examples. Semiconductor regions of the same conductivity type are hatched in the same direction as a rule.
The invention is not limited to the embodiments given, since many modifications and variations are possible to those skilled in the art within the scope of the invention. Thus different thicknesses, different semiconductor materials or different compositions from those mentioned in the examples may be used. It is noted in particular that the invention may also be applied to the material systems GaAs/AlGaAs and InGaP/InAlGaP. It is further noted that the invention may be used to great advantage not only in the manufacture of the structures mentioned in the examples, but also for other structures, for example, which do not comprise mesas. An example of an alternative structure comprising a mesa is the SIPBH (=Semi-Insulating Planar Buried Hetero) structure. Examples of alternative structures not containing a mesa are so-called oxide strip or proton bombarded lasers, generally, lasers of the so-called gain guided type. It is finally noted that one or more of the three growing processes forming part of the method according to the invention may employ growing techniques other than MOVPE, such as the LPE technique already mentioned, VPE (=Vapour Phase Epitaxy) and MBE (=Molecular Beam Epitaxy). | A method of manufacturing an optoelectronic semiconductor device includes the step of providing two comparatively thin layers next to one another on a substrate by means of a non-selective growing process, an etching process, and a selective growing process, a cladding layer being present over said thin layers. In the known method, first the one thin layer and the cladding layer are grown, the latter is locally removed, and the other thin layer and the cladding layer are then grown in that position. This method has the disadvantage that unevennesses (steps or openings) often arise at the surface of the layer structure above the transition between the thin layers. In the present method, in a first non-selective growing process the one layer and a small portion of the cladding layer are provided, these layers are locally removed in the etching process, and the other thin layer and a small portion of the cladding layer are provided in that location in the selective growing process, after which in a second non-selective growing process the major portion of the cladding layer is provided. The layer structure obtained has a substantially plane surface which is free from defects and is very suitable for further processing. The thin layers may be, inter alia, an active and a radiation-guiding layer. In particular, devices having a mesa structure can be manufactured with a high accuracy and yield. | 7 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application claims priority to U.S. Provisional Application No. 60/357,878, filed Feb. 21,2002, titled “Delay Circuit With Delay Relatively Independent of Process, Voltage, and Temperature Variations,” incorporated herein by reference in its entirety.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention is directed to delay circuits and, more particularly, to delay circuits that are implemented in integrated circuits that are fabricated with reduced feature-size technologies, wherein the delay circuits compensate for process, supply-voltage and/or temperature variations that could otherwise affect the integrated circuits.
2. Background Art
Integrated circuits are fabricated using reduced feature-size technologies, which have significant variations in device characteristics across the process, supply-voltage and temperature (PVT) corners. PVT variations can lead to reduced rise and/or fall times. Reduced rise and/or fall times tend to appear as unexpected delay because the signals do not reach their intended level until later than expected. For extracting maximum benefit from a given process technology, among other things, the delay across various paths of the circuit has to be controlled such that the delay variation across PVT is minimal.
Methods and systems are needed for controlling delay caused by PVT variations.
BRIEF SUMMARY OF THE INVENTION
The present invention is directed to methods and systems that enable control of delay, relatively independent of process, supply-voltage and/or temperature (“PVT”) variations. This is made possible by, for example, sensing the output signal after a pre-determined number of inverters and adjusting the gate drive of transistors in the delay path to compensate for PVT variations.
Further features and advantages of the invention, as well as the structure and operation of various embodiments of the invention, are described in detail below with reference to the accompanying drawings. It is noted that the invention is not limited to the specific embodiments described herein. Such embodiments are presented herein for illustrative purposes only. Additional embodiments will be apparent to persons skilled in the relevant art(s) based on the teachings contained herein.
BRIEF DESCRIPTION OF THE DRAWINGS/FIGURES
The present invention will be described with reference to the accompanying drawings. The drawing in which an element first appears is typically indicated by the leftmost digit(s) in the corresponding reference number.
FIG. 1 is a schematic diagram of a delay block in accordance with an aspect of the invention.
FIG. 2 is a block diagram of a series of delay blocks, in accordance with an aspect of the invention.
FIG. 3 is a logic diagram of a delay block in accordance with an aspect of the invention.
FIG. 4 is a schematic diagram of another delay block in accordance with an aspect of the invention.
FIG. 5 is a schematic diagram of another delay block in accordance with an aspect of the invention.
FIG. 6 is a schematic diagram of another delay block in accordance with an aspect of the invention.
FIG. 7 is an example process flowchart for compensating for PVT variations, in accordance with an aspect of the invention.
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 illustrates an example PVT-compensated delay block (“delay block”) 100 , in accordance with the invention. The delay block 100 includes a rising edge path 102 and a falling edge path 104 . The rising edge path 102 processes rising edges of a received waveform 108 . The falling edge path 104 processes falling edges of the received waveform 108 . In an alternative embodiment only the rising edge path 102 or the falling edge path 104 is implemented.
The rising edge path 102 includes a weak path 102 A and a strong path 102 B. Similarly, the falling edge path 104 includes a weak path 104 A and a strong path 104 B. The weak paths 102 A and 104 A include one or more relatively weak transistors. The strong paths 102 B and 104 B include one or more relatively strong transistors.
When used herein, the phrases, “weak transistor” and “strong transistor” refer to relative drive capabilities of transistors. Weak transistors are transistors with lower width/length ratios. Strong transistors are transistors with higher width/length ratios. Weak transistors are advantageous because they typically require lower power supply voltage level and typically consume less power than strong transistors. Weak transistors are thus often preferred where power consumption is sought to be minimized. Weak transistors, however, tend to be more susceptible to PVT variations than strong transistors. PVT variations typically result in reduced rise times and/or reduced fall times. Reduced rise and/or fall times tend to appear as increased delay because the waveform does not reach a desired amplitude until later than expected.
The weak paths 102 A and 104 A receive the input waveform 108 from an input terminal 110 . The weak paths 102 A and 104 A delay the received waveform 108 by a desired amount and output a delayed waveform 126 at an output terminal 128 . In the example of FIG. 1, the weak paths 102 A and 104 A include a series of inverters. The invention is not limited, however, to this example. The weak paths 102 A and 104 A may include any suitable circuitry that is susceptible to PVT variations.
The strong paths 102 B and 104 B receive feedback from the weak paths 102 A and 104 A, respectively. In FIG. 1, a feedback block 106 is coupled between the output terminal 128 and the strong paths 102 B and 104 B. When feedback indicates that the weak paths 102 A and/or 104 A are adversely affected by PVT variations, (e.g., reduced rise and/or fall times), the associated strong path 102 B and/or strong path 104 B provide additional output drive power to correct for the PVT variations. The additional output drive power increases the rise and/or fall times of the delayed waveform, thus compensating for the PVT variations.
Functional features of the delay block 100 are illustrated in FIG. 3, with a logic block diagram 300 .
Operation of the delay block 100 , as illustrated in FIG. 1, is now described. The description begins with rising edge path 102 . Within the rising edge path 102 , the rising edge weak path 102 A includes a circuit element 112 and an output driver 122 . The circuit element 112 includes an inverter 114 , implemented here with a PMOS device 116 and an NMOS device 118 . The inverter 114 , has an inherent amount of delay. Additional inverters 114 can be added if desired. The output driver 122 includes a PMOS device 124 which typically includes an additional inherent delay.
The rising edge weak path 102 A receives the input waveform 108 from the input terminal 110 . The circuit element 112 delays the waveform 108 by some desired amount and outputs an interim delayed waveform 120 to the output driver 122 . The PMOS device 124 optionally further delays the interim delayed waveform 120 and outputs the output delayed waveform 126 to the output terminal 128 .
Where, as in this example, the circuit element 112 includes an inverter, the interim delayed waveform 120 is an inverted delayed representation of the input waveform 108 . The PMOS device 124 inverts the interim delayed form 120 and outputs the output delayed waveform 126 .
Where, as in this example, the rising edge weak path 102 A includes inverters, an even number of inverters is preferably used. In this way, output delayed waveform 126 will be substantially similar to the input waveform 108 , but delayed in time by the inherent delay of the circuit element(s) 112 and the output driver 122 .
In accordance with the invention, the output driver 122 and, optionally, the circuit element 112 are implemented with one or more relatively weak transistor devices, meaning devices that consume relatively little power. Under normal operating conditions, as the input waveform 108 rises, the output delayed waveform 126 from the rising edge weak path 102 A also rises, but delayed in time by an expected amount of time relative to the input waveform 108 . However, when process, supply-voltage, and/or temperature (“PVT”) variations adversely affect the relatively weak transistor devices within rising edge weak path 102 A, the output delayed waveform 126 will rise and/or fall more slowly than the input waveform 108 . This will make the output delayed waveform 126 appear to be delayed more than the expected delay time.
The falling edge weak path 104 A operates in a manner similar to the rising edge weak path 102 A, taking into account that the rising edge weak paths pulls the output signal 128 up, while the falling edge weak path pulls the output signal 128 down.
In order to compensate for PVT variations, the feedback block 106 senses conditions of the output delayed waveform 126 , and controls the strong paths 102 B and 104 B to provide additional output drive, as needed, to compensate for PVT variations. The feedback block 106 receives the delayed output waveform 126 and outputs a feedback signal 136 to the strong paths 102 B and 104 B. The feedback block 106 varies the feedback signal 136 in accordance with the level of the output delayed waveform 126 .
In the example of FIG. 1, the feedback block 106 includes an inverter 130 , implemented as a PMOS device 132 and an NMOS device 134 . As the output delayed waveform 126 rises, the feedback signal 136 falls. Conversely, as the output delayed waveform 126 falls, the feedback signal 136 rises. The feedback signal 136 is provided to a node 145 , which is coupled to the strong paths 102 B and 104 B.
In the example of FIG. 1, the rising edge strong path 102 B and the falling edge strong path 104 B are designed to provide supplemental output drive unless the feedback block 106 disables the strong paths 102 B and 104 B. The feedback block 106 disables the strong paths 102 B and 104 B when the output delayed waveform 126 rises or falls within the expected time.
The rising edge strong path 102 B is now described. The rising edge strong path 102 B includes an output driver 148 , implemented here with a PMOS device 150 . The PMOS device 150 includes a drain terminal coupled to VDD and a source terminal coupled to the output terminal 128 . A gate terminal of the PMOS device 150 is controlled by a voltage at a node 144 . The voltage at the node 144 controls the PMOS device 150 as follows. As the voltage at the node 144 falls, the PMOS-device 150 turns on, which increasingly couples VDD to the output terminal 128 . This increases the current to the output terminal 128 . As the voltage at the node 144 rises, the PMOS device 150 turns off, increasingly isolating VDD from the output terminal 128 . This decreases the current provided to the output terminal 128 .
Control of the voltage at the node 144 is now described. The rising edge strong path 102 B further includes PMOS devices 138 and 146 , and NMOS devices 140 and 142 . Recall that when the output delayed waveform is low, the feedback signal 136 at the node 145 is high. This turns on the NNTOS device 142 . When the NMOS device 142 turns on, the PMOS device 138 and the NMOS device 140 form an inverter. The PMOS device 138 and the NMOS device 140 include gate terminals coupled to the input terminal 110 , which forms the input of the inverter. The inverter formed by the PMOS device 138 and the NMOS device 140 has an inherent delay, so that a delayed, inverted representation of the input waveform 108 appears at the node 144 . As the input waveform 108 rises, the output of the inverter, node 144 , falls. As described above, this increasingly turns on the PMOS 150 , which pulls the output terminal 128 toward VDD. In other words, as the input waveform 108 rises, and when the output delayed waveform 126 is slow to rise relative to the delayed inverter waveform at the node 144 , the rising edge strong path 102 B pulls up the output terminal 128 toward VDD.
When the level at the output terminal 128 rises, the feedback signal 136 disables the PMOS device 150 , as now described. Recall that, as the output waveform 126 rises, the feedback signal 136 falls. As the feedback signal 136 falls, the NMOS device 142 turns off, which isolates the node 144 from the NMOS device 140 . This prevents the NMOS device 140 from pulling down the node 144 . Furthermore, as the feedback signal 136 falls, it controls a gate terminal of the PMOS device 146 to increasingly couple VDD to the node 144 . As the node 144 rises toward VDD, it increasingly turns off the PMOS device 150 . This increasingly isolates VDD from the output terminal 128 , which reduces the supplemental drive provided to the output terminal 128 . At this point, the rising edge weak path driver PMOS device 124 should be able to drive the output delayed waveform 126 .
The rising edge weak path 102 A and the rising edge strong path 102 B are designed with relative delays and transistor thresholds so that, under normal operating conditions, when the input waveform 108 rises, the output delayed waveform 126 rises within a desired delay time. When this occurs, the feedback signal 136 falls quickly enough to couple the node 144 to VDD, disabling the output driver 148 before the input waveform 108 propagates through the NMOS device 140 to the node 144 . When, however, the output delayed waveform 126 does not rise withing the desired delay time, the input waveform 108 propagates through the NMOS device 140 to the node 144 and turns on the PMOS device 150 . The PMOS device 150 remains on until the feedback signal 136 falls in response to the rising output delayed waveform 126 , or until the input waveform 108 falls.
When the input signal 108 falls, the PMOS device 150 terminates the output drive from the rising edge strong path 102 B as follows. When the input signal 108 falls, the NMOS device 140 turns off, isolating the node 144 from the low potential VSS. Furthermore, as the input signal 108 falls, the PMOS device 138 turns on, coupling the node 144 to VDD, which turns off the PMOS device 150 . Thus, as the input signal 108 falls, the output driver 148 terminates the output drive from the rising edge strong path 102 B. Similarly, as the input waveform 108 falls, the output of the inverter 114 in rises, turning off the PMOS device 124 , thus terminating the output of the rising edge weak path 102 A. Furthermore, as the input signal 108 falls, falling edge path 104 pulls the output delayed waveform 126 down to the potential of VSS in a similar fashion to the rising edge path 102 , as will be apparent to one skilled in the relevant art(s) based on the description herein.
The present invention thus allows use of reduced feature-size technologies for normal operation, while providing back-up circuitry to provide compensation as needed, such as for PVT variations.
FIG. 2 is a block diagram of multiple delay blocks 100 coupled in series to obtain a desired overall delay. A first delay block 100 A receives the waveform 108 and outputs a delayed waveform 126 a , substantially as described above with respect to FIG. 1. A second delay block 100 B receives the outputted delayed waveform 126 a and delays it further and outputs delayed waveform 126 b . This is repeated by subsequent delay blocks through to delay block 120 i , which outputs a final output delayed waveform 126 i.
FIG. 4 illustrates another example embodiment of the delay block 100 .
In this example, the rising edge weak path 102 a and the falling edge weak path 104 a are integrated into a single weak path 402 , while the feedback block 106 is implemented with a rising edge feedback block 106 a and a falling edge feedback block 106 b . The weak path 402 includes multiple circuit elements 112 , illustrated here as an inverters 114 a - 114 c , and inverting output driver 122 . In this embodiment, the inverter 114 a is referred to as an initial delay element, and the inverting output driver 122 is referred to as a final delay element. Operation of the delay block 100 illustrated in FIG. 4 is substantially similar to operation of the delay block 100 illustrated in FIG. 1 .
In accordance with the invention, one or more of the devices within the weak paths 102 A, 104 A, and 402 are relatively weak devices, and one or more of the devices within the strong paths 102 B, 104 B are relatively strong devices. In the example of FIG. 4, and without limitation, the weak path 402 includes a PMOS device 410 implemented with widths of approximately 0.93 microns and lengths of approximately 0.39 microns, and an NMOS device 418 implemented with widths of approximately 0.49 microns and lengths of approximately 0.39 microns. Within the rising edge strong path 102 B, the PMOS device 150 is implemented with widths of approximately 0.93 microns and lengths of approximately 0.13 microns. Within the falling edge strong path 104 B, the NMOS device 152 is implemented with widths of approximately 0.49 microns and lengths of approximately 0.13 microns. The invention is not, however, limited to these examples. Based on the description herein, one skilled in the relevant art(s) will understand that other widths, lengths, and/or width/length ratios can be implemented as well.
FIG. 5 illustrates another example embodiment of the delay block 100 , wherein the feedback blocks 106 A and 106 B are designed to sense current at the output terminal 128 . In previous drawing figures, the feedback block 106 was designed to sense primarily voltage levels at the output terminal 128 .
In FIG. 5, feedback block 106 A includes a PMOS device 502 , configured as a capacitor, and an NMOS device 504 configured as a diode. As the output delayed waveform 126 voltage increases with time (dV/dt), a current flows from a gate of the PMOS device 502 to a node 510 . This current flows through diode connected NMOS device 504 to a relatively low potential, illustrated here as ground. The current flow thought the diode connected NMOS device 504 generates a voltage at the node 510 , proportional to the dV/dt of the output delayed waveform 126 .
The feedback block 106 A further includes an inverter formed by a PMOS device 506 and an NMOS device 508 . The inverter inverts the signal at the node 510 and outputs the inverted signal at a node 136 a . In operation, when the dV/dt of the output delayed waveform 126 is sufficiently high, the voltage at the node 510 increases. As the voltage at the node 510 increases, the voltage at the node 136 a decreases. As the voltage at the node 136 a decreases, the PMOS device 146 increasingly turns on, which turns off the output driver PMOS device 150 . In other words, when the output delayed waveform 126 rises at or greater than a desired dV/dt, the output driver 150 does not provide supplemental output drive.
Another way of analyzing the operation of the feedback block 106 A is to consider the current flow. The NMOS device 504 forms a current mirror with the NMOS device 508 . The width/length ratios of the NMOS devices 504 and 508 determine the current ratio between the NMOS devices 504 and 508 . As the current through the NMOS device 508 increases, it pulls down the node 136 a.
An optional enable/disable feature is provided by a line 514 coupled between an output of the first inverter 114 a and a gate terminal of an NMOS device 512 . When the input waveform 110 falls, the output of the first inverter 114 a rises. This turns on the NMOS device 512 , which couples the node 510 to ground. This turns on the PMOS device 506 , which couples the node 136 a to VDD. This turns off the PMOS device 146 , which effectively prevents the feedback block 106 A from disabling the PMOS device 150 .
The falling edge feedback block 106 B operates in a similar fashion to the rising edge feedback block 106 A, taking into account that the falling edge strong path 104 B pulls the output terminal 128 down when the input waveform 108 falls.
FIG. 6 illustrates another example implementation of the delay block 100 , wherein the delay block 100 includes multiple circuit elements 112 a , 112 b , and wherein the feedback block receives feedback from a point prior to the output terminal 128 . In the example of FIG. 6, the feedback blocks 106 A and 106 B receive an interim delayed waveform 602 from the circuit element 112 a . Where the feedback blocks 106 A and 106 B receive an interim delayed waveform 602 from a subsequent circuit element 112 , additional delay circuitry can be included in the feedback blocks 106 A and 106 B, and/or in the strong paths 102 A and 102 B, to compensate for the additional delay encountered in the subsequent circuit elements 112 . The rising edge strong path 102 B and the falling edge strong path 104 B provide compensation 604 to the output terminal 128 , substantially as described above. Delay in subsequent delay elements, illustrated here as circuit element 112 B, can be accounted for with one or more compensation-path delay elements 606 .
An advantage of the delay block 100 illustrated in FIG. 6 is that the single set of feedback blocks 106 A and 106 B, and a single set of rising edge strong path 102 B and falling edge strong path 104 B are required for a plurality of circuit elements 112 . One or more of the delay blocks 100 illustrated in FIG. 2 can be implemented as illustrated in FIG. 6 .
FIG. 7 illustrates a process flowchart 700 in accordance with an aspect of the invention. The process flowchart 700 is described with reference to the example delay block 100 illustrated in FIGS. 1 through 6. The process flowchart 700 is not, however, limited to the example output block 100 illustrated in FIGS. 1 through 6. Based on the description herein, one skilled in the relevant art(s) will understand that the process flowchart 700 can be implemented with other circuits as well. Such other implementations are within the spirit and scope of the present invention.
The process begins at step 702 , which includes, receiving a waveform. In the example of FIG. 1, the waveform 108 is received at the input terminal 110 .
Step 704 includes delaying the waveform. In the example of FIG. 1, rising edges of the waveform 108 are delayed by the circuit element 112 in the rising edge weak path 102 A, which outputs the delayed waveform 120 . Falling edges of the waveform 108 are delayed by the circuit element 112 in the falling edge weak path 104 A.
Step 706 includes outputting the delayed waveform to an output terminal using at least one lower-power driver transistor. In the example of FIG. 1, the PMOS device 124 outputs rising edges of the delayed waveform 108 as an output delayed signal 126 to the output terminal 128 . Falling edges of the delayed waveform 108 are output to the output terminal 128 by the falling edge weak path 104 A. The invention is not, however, limited to this example embodiment.
Step 708 includes providing supplemental output drive to the output terminal after an expected period of delay, using at least one higher-power driver transistor. In the example of FIG. 1, supplemental output drive is provided by the strong paths 102 B and 104 B, after an inherent delay of the strong paths 102 B and 104 B. The invention is not, however, limited to this example embodiment.
Step 710 includes sensing a level of the delayed waveform. Step 710 can be performed by sensing voltage and/or current levels. In the examples of FIGS. 1, 4 , and 6 , the feedback block 106 senses primarily voltage levels. In the example of FIG. 5, the feedback block 106 senses primarily current levels.
Step 712 includes reducing the supplemental output drive as the sensed level rises above a threshold. In the example of FIG. 1, the feedback block 106 disables the output drivers in the strong paths 102 B and 104 B when the output delayed signal 106 rises above a threshold. For example, the feedback block 106 disables the PMOS device 150 when the output delayed signal 106 causes the feedback signal 136 to fall low enough to turn on the PMOS device 146 , as described above.
Steps 704 - 712 are performed for rising edge and falling edge portions of the received waveform, as illustrated in FIGS. 1-6. Steps(1) through (5) can be repeated using the first output delayed signal as a second input signal, thereby further delaying the received waveform while compensating for PVT variations, as illustrated in FIG. 2 .
The process flowchart 700 can be implemented to delay a received waveform with multiple delay operations, as illustrated, for example, in FIG. 6 . In this embodiment, step 704 includes performing a plurality of serial delay operations, including at least one initial delay operation and a final delay operation, on the received waveform. Step 708 includes providing supplemental output drive to the output terminal through one or more compensation-path delay elements, as illustrated by the compensation-path delay elements 606 in FIG. 6 . Step 710 includes sensing a level of the delayed waveform output from one of the initial delay operations, as illustrated in FIG. 6 .
The present invention has been described above with the aid of functional building blocks illustrating the performance of specified functions and relationships thereof. The boundaries of these functional building blocks have been arbitrarily defined herein for the convenience of the description. Alternate boundaries can be defined so long as the specified functions and relationships thereof are appropriately performed. Any such alternate boundaries are thus within the scope and spirit of the claimed invention. One skilled in the art will recognize that these functional building blocks can be implemented by discrete components, application specific integrated circuits, processors executing appropriate software and the like or any combination thereof.
When used herein, the terms “connected” and/or “coupled” are generally used to refer to electrical connections. Such electrical connections can be direct electrical connections with no intervening components, and/or indirect electrical connections through one or more components.
While various embodiments of the present invention have been described above, it should be understood that they have been presented by way of example only, and not limitation. Thus, the breadth and scope of the present invention should not be limited by any of the above-described exemplary embodiments, but should be defined only in accordance with the following claims and their equivalents. | Methods and systems for controlling delay relatively independent of process, supply-voltage, and/or temperature (“PVT”) variations include sensing an output signal after a number of inverters and activating different numbers of transistors and/or adjusting strength of transistors in a delay path to compensate for PVT variations. In an embodiment, a waveform is received, delayed, and output to an output terminal using at least one relatively low-power device. Supplemental output power is provided by at least one relatively high-power device until the output waveform exceeds a threshold. | 7 |
STATEMENT OF GOVERNMENT INTEREST
The invention described herein may be made, used or licensed by or for the Government for Government purposes without the payment of any royalty to me.
FIELD AND BACKGROUND OF THE INVENTION
Currently practiced methods of measuring the azimuth angle of smoke grenade launcher tubes mounted on vehicles or test fixtures are unsatisfactory. They require the precise set-up and use of complicated surveying equipment and complex mathematical computations. These methods are slow, tedious, and of questionable accuracy, given the assumptions that are made relative to the geometry of the problem, and the accumulated errors in measurement.
A need remains for a simple technique for taking the horizontal azimuth angle of a launcher tube using inexpensive and easily manipulated equipment.
SUMMARY OF THE INVENTION
The method of the present invention allows an azimuth angle to be measured quickly and directly with an inexpensively fabricated fixture and a commercially available compass, for example, an electronic compass.
Accordingly, an object of the present invention is to provide a method of determining the azimuth of a grenade launcher tube having a centerline which is elevated at an elevation angle, comprising: extending a straight line marker parallel to the centerline, the marker having an outer end spaced from the tube; hanging an elongated plumb bob vertically from the end of the marker; sighting along a substantially horizontal line of sight which lies in a plane containing the plumb bob and the marker; and reading a horizontal bearing of the line of sight which corresponds to the azimuth of the tube.
A further object of the present invention is to provide an inexpensive fixture for use in practicing the inventive method.
The various features of novelty which characterize the invention are pointed out with particularity in the claims annexed to and forming a part of this disclosure. For a better understanding of the invention, its operating advantages and specific objects attained by its uses, reference is made to the accompanying drawings and descriptive matter in which a preferred embodiment of the invention is illustrated.
BRIEF DESCRIPTION OF THE DRAWING
The only drawing in the application is a perspective view of a fixture used to practice the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to the drawing in particular, the invention embodied therein comprises a fixture for use in quickly, inexpensively and accurately determining the azimuth of a smoke grenade launcher tube 10, that is the substantially horizontal angle around an azimuth schematically illustrated at 40, on which a grenade launched from the tube will travel in its parabolic flight from the tube.
The fixture comprises a plug 12 of metal, plastic or wood, which is shaped and dimensioned to closely fit within the bore of the launcher tube 10. The size and shape of plug 12 should be such that the fixture can easily be inserted and removed from the tube but further so that an extension 14 having a flat surface containing a straight line marker 16, lies parallel to the centerline of the tube. Extension 14 is advantageously an inexpensive U-shaped channel of metal or plastic. Marker 16 can simply be painted, adhered or otherwise defined on the flat web of the channel 14.
A wire or other freely moveable connector 22 is attached to the free outer end of channel 14, at the outer end of marker 16. An elongated plumb bob 18, 20 extends downwardly from wire 22 and hangs vertically under the force of gravity. The plumb bob comprises an elongated rod 18 having a weight 20 connected at its lower free end. Any other elongated member with weight can be used.
In order to use the fixture of the present invention, one walks around an arc on the azimuth 40, until a line of sight 30 is visually aligned with the elongated plump bob rod 18 lying over and parallel to the line marker 16. For this purpose, contrasting colors should be used between the elongated plumb bob and marker. With sighting along line 30, marker 16, rod 18 and line of sight 30 form a triangular shape which lies in the plane that also contains the parabolic flight path for the grenade to be launched from the tube 10. Using any commercially available compass device, for example, an electronic compass, the bearing of substantially horizontal line of sight 30 is taken. This provides a measurement which corresponds precisely to the horizontal azimuth for the tube 10. As a practical matter since sighting is taking place in an opposite direction to the actual flight path of the grenade, 180° should be added to whatever angular bearing is given by the compass, to give the actual azimuth for the launcher tube. Although the line of sight 30 and the azimuth arc 40 should be substantially horizontal, this encompasses inclines necessitated by terrain on which the tube or it vehicle, are mounted.
The present invention thus provides a versatile, extremely simple, effective and accurate method of measuring azimuth using inexpensive equipment and a commercially available compass. By walking on an arc of about 20 to 30 paces around the tube, the line of sight 30 can be taken with minimum difficultly.
While a specific embodiment of the invention has been shown and described in detail to illustrate the application of the principles of the invention, it will be understood that the invention may be embodied otherwise without departing from such principles. | A method for measuring the azimuth angles of grenade launcher tubes quicklynd directly, uses an easily fabricated, portable fixture and a commercially available hand-held electronic compass. There is not need for a precise set-up of complex equipment or mathematical computations. | 5 |
CROSS REFERENCES TO RELATED APPLICATIONS
[0001] The present application is a continuation of U.S. application Ser. No. 12/422,952 filed Apr. 13, 2009, which is a continuation of U.S. application Ser. No. 12/036,910 filed Feb. 25, 2008, now issued U.S. Pat. No. 7,517,053, which is a continuation of U.S. application Ser. No. 11/707,946 filed on Feb. 20, 2007, now issued U.S. Pat. No. 7,354,208 which is a continuation of U.S. application Ser. No. 10/296,524 filed on Jul. 7, 2003, now issued U.S. Pat. No. 7,210,867, which is a 371 of PCT/AU00/00598 filed on May 24, 2000 all of which are herein incorporated by reference.
BACKGROUND OF THE INVENTION
[0002] The following invention relates to a paper thickness sensor in a printer.
[0003] More particularly, though not exclusively, the invention relates to a paper thickness sensor used for adjusting the space between a printhead and a platen in an A4 pagewidth drop on demand printer capable of printing up to 1600 dpi photographic quality at up to 160 pages per minute.
[0004] The overall design of a printer in which the paper thickness sensor can be utilized revolves around the use of replaceable printhead modules in an array approximately 8 inches (20 cm) long. An advantage of such a system is the ability to easily remove and replace any defective modules in a printhead array. This would eliminate having to scrap an entire printhead if only one chip is defective.
[0005] A printhead module in such a printer can be comprised of a “Memjet” chip, being a chip having mounted thereon a vast number of thermo-actuators in micro-mechanics and micro-electromechanical systems (MEMS). Such actuators might be those as disclosed in U.S. Pat. No. 6,044,646 to the present applicant, however, there might be other MEMS print chips.
[0006] The printhead, being the environment within which the paper thickness sensor of the present invention is to be situated, might typically have six ink chambers and be capable of printing four color process (CMYK) as well as infra-red ink and fixative. An air pump would supply filtered air to the printhead, which could be used to keep foreign particles away from its ink nozzles. The printhead module is typically to be connected to a replaceable cassette which contains the ink supply and an air filter.
[0007] Each printhead module receives ink via a distribution molding that transfers the ink. Typically, ten modules butt together to form a complete eight inch printhead assembly suitable for printing A4 paper without the need for scanning movement of the printhead across the paper width.
[0008] The printheads themselves are modular, so complete eight inch printhead arrays can be configured to form printheads of arbitrary width.
[0009] Additionally, a second printhead assembly can be mounted on the opposite side of a paper feed path to enable double-sided high speed printing.
CO-PENDING APPLICATIONS
[0010] Various methods, systems and apparatus relating to the present invention are disclosed in the following co-pending applications filed by the applicant or assignee of the present invention simultaneously with the present application:
[0011] PCT/AU00/00518, PCT/AU00/00519, PCT/AU00/00520, PCT/AU00/00521,
[0012] PCT/AU00/00522, PCT/AU00/00523, PCT/AU00/00524, PCT/AU00/00525,
[0013] PCT/AU00/00526, PCT/AU00/00527, PCT/AU00/00528, PCT/AU00/00529,
[0014] PCT/AU00/00530, PCT/AU00/00531, PCT/AU00/00532, PCT/AU00/00533,
[0015] PCT/AU00/00534, PCT/AU00/00535, PCT/AU00/00536, PCT/AU00/00537,
[0016] PCT/AU00/00538, PCT/AU00/00539, PCT/AU00/00540, PCT/AU00/00541,
[0017] PCT/AU00/00542, PCT/AU00/00543, PCT/AU00/00544, PCT/AU00/00545,
[0018] PCT/AU00/00547, PCT/AU00/00546, PCT/AU00/00554, PCT/AU00/00556,
[0019] PCT/AU00/00557, PCT/AU00/00558, PCT/AU00/00559, PCT/AU00/00560,
[0020] PCT/AU00/00561, PCT/AU00/00562, PCT/AU00/00563, PCT/AU00/00564,
[0021] PCT/AU00/00565, PCT/AU00/00566, PCT/AU00/00567, PCT/AU00/00568,
[0022] PCT/AU00/00569, PCT/AU00/00570, PCT/AU00/00571, PCT/AU00/00572,
[0023] PCT/AU00/00573, PCT/AU00/00574, PCT/AU00/00575, PCT/AU00/00576,
[0024] PCT/AU00/00577, PCT/AU00/00578, PCT/AU00/00579, PCT/AU00/00581,
[0025] PCT/AU00/00580, PCT/AU00/00582, PCT/AU00/00587, PCT/AU00/00588,
[0026] PCT/AU00/00589, PCT/AU00/00583, PCT/AU00/00593, PCT/AU00/00590,
[0027] PCT/AU00/00591, PCT/AU00/00592, PCT/AU00/00584, PCT/AU00/00585,
[0028] PCT/AU00/00586, PCT/AU00/00594, PCT/AU00/00595, PCT/AU00/00596,
[0029] PCT/AU00/00597, PCT/AU00/00598, PCT/AU00/00516, PCT/AU00/00517,
[0030] PCT/AU00/00511, PCT/AU00/00501, PCT/AU00/00502, PCT/AU00/00503,
[0031] PCT/AU00/00504, PCT/AU00/00505, PCT/AU00/00506, PCT/AU00/00507,
[0032] PCT/AU00/00508, PCT/AU00/00509, PCT/AU00/00510, PCT/AU00/00512,
[0033] PCT/AU00/00513, PCT/AU00/00514, PCT/AU00/00515
[0034] The disclosures of these co-pending applications are incorporated herein by cross-reference.
OBJECTS OF THE INVENTION
[0035] It is an object of the present invention to provide a paper thickness sensor in a printer.
[0036] It is another object of the present invention to provide a paper thickness sensor used for adjusting a printhead-to-platen clearance for the pagewidth printhead assembly as broadly described herein.
[0037] It is another object of the present invention to provide a pagewidth printhead assembly having a paper thickness sensor therein to aid in adjusting a printhead-to-platen clearance.
[0038] It is yet another object of the present invention to provide a method of adjusting the clearance between a printhead and a platen in a pagewidth printhead assembly.
SUMMARY OF THE INVENTION
[0039] The present invention provides a pagewidth printer comprising:
a printhead having an array of fixed printing nozzles thereon, a platen having a platen surface upon which a sheet rides to receive on a print surface thereof ink from said printing nozzles, a sensor to measure an offset of said print surface with respect to said printing nozzles, and means to effect movement of said platen to alter said offset.
[0044] Preferably the platen is mounted so as to rotate about a longitudinal axis thereof and said platen surface extends along the platen parallel with said axis at a non-constant distance from said axis such that compensatory rotation of the platen effects the offset of said print surface with respect to said printing nozzles.
[0045] Preferably the sensor is an optical sensor.
[0046] Preferably the optical sensor senses the position of a pivotal sensor flag that engages the print surface.
[0047] Preferably the sensor flag is mounted upon a spring-biased pivotal shaft mounted to the printhead.
[0048] The present invention also provides a method of adjusting an offset between an array of printing nozzles on a printhead and a print surface of a sheet riding upon a platen, the method comprising the steps of sensing the offset between the printhead and the print surface of the sheet and moving the platen so as to make any necessary compensation to said offset.
[0049] Preferably the platen includes a longitudinal axis and a platen surface parallel with said axis at a non-constant distance from said axis, the method including effecting compensatory rotation of the platen.
[0050] As used herein, the term “ink” is intended to mean any fluid which flows through the printhead to be delivered to a sheet. The fluid may be one of many different coloured inks, infra-red ink, a fixative or the like.
BRIEF DESCRIPTION OF THE DRAWINGS
[0051] A preferred form of the present invention will now be described by way of example with reference to the accompanying drawings wherein:
[0052] FIG. 1 is a front perspective view of a print engine assembly
[0053] FIG. 2 is a rear perspective view of the print engine assembly of FIG. 1
[0054] FIG. 3 is an exploded perspective view of the print engine assembly of FIG. 1 .
[0055] FIG. 4 is a schematic front perspective view of a printhead assembly.
[0056] FIG. 5 is a rear schematic perspective view of the printhead assembly of FIG. 4 .
[0057] FIG. 6 is an exploded perspective illustration of the printhead assembly.
[0058] FIG. 7 is a cross-sectional end elevational view of the printhead assembly of FIGS. 4 to 6 with the section taken through the centre of the printhead.
[0059] FIG. 8 is a schematic cross-sectional end elevational view of the printhead assembly of FIGS. 4 to 6 taken near the left end of FIG. 4 .
[0060] FIG. 9A is a schematic end elevational view of mounting of the print chip and nozzle guard in the laminated stack structure of the printhead
[0061] FIG. 9B is an enlarged end elevational cross section of FIG. 9A
[0062] FIG. 10 is an exploded perspective illustration of a printhead cover assembly.
[0063] FIG. 11 is a schematic perspective illustration of an ink distribution molding.
[0064] FIG. 12 is an exploded perspective illustration showing the layers forming part of a laminated ink distribution structure according to the present invention.
[0065] FIG. 13 is a stepped sectional view from above of the structure depicted in FIGS. 9A and 9B ,
[0066] FIG. 14 is a stepped sectional view from below of the structure depicted in FIG. 13 .
[0067] FIG. 15 is a schematic perspective illustration of a first laminate layer.
[0068] FIG. 16 is a schematic perspective illustration of a second laminate layer.
[0069] FIG. 17 is a schematic perspective illustration of a third laminate layer.
[0070] FIG. 18 is a schematic perspective illustration of a fourth laminate layer.
[0071] FIG. 19 is a schematic perspective illustration of a fifth laminate layer.
[0072] FIG. 20 is a perspective view of the air valve molding
[0073] FIG. 21 is a rear perspective view of the right hand end of the platen
[0074] FIG. 22 is a rear perspective view of the left hand end of the platen
[0075] FIG. 23 is an exploded view of the platen
[0076] FIG. 24 is a transverse cross-sectional view of the platen
[0077] FIG. 25 is a front perspective view of the optical paper sensor arrangement
[0078] FIG. 26 is a schematic perspective illustration of a printhead assembly and ink lines attached to an ink reservoir cassette.
[0079] FIG. 27 is a partly exploded view of FIG. 26 .
DETAILED DESCRIPTION OF THE INVENTION
[0080] In FIGS. 1 to 3 of the accompanying drawings there is schematically depicted the core components of a print engine assembly, showing the general environment in which the laminated ink distribution structure of the present invention can be located. The print engine assembly includes a chassis 10 fabricated from pressed steel, aluminium, plastics or other rigid material. Chassis 10 is intended to be mounted within the body of a printer and serves to mount a printhead assembly 11 , a paper feed mechanism and other related components within the external plastics casing of a printer.
[0081] In general terms, the chassis 10 supports the printhead assembly 11 such that ink is ejected therefrom and onto a sheet of paper or other print medium being transported below the printhead then through exit slot 19 by the feed mechanism. The paper feed mechanism includes a feed roller 12 , feed idler rollers 13 , a platen generally designated as 14 , exit rollers 15 and a pin wheel assembly 16 , all driven by a stepper motor 17 . These paper feed components are mounted between a pair of bearing moldings 18 , which are in turn mounted to the chassis 10 at each respective end thereof.
[0082] A printhead assembly 11 is mounted to the chassis 10 by means of respective printhead spacers 20 mounted to the chassis 10 . The spacer moldings 20 increase the printhead assembly length to 220 mm allowing clearance on either side of 210 mm wide paper.
[0083] The printhead construction is shown generally in FIGS. 4 to 8 .
[0084] The printhead assembly 11 includes a printed circuit board (PCB) 21 having mounted thereon various electronic components including a 64 MB DRAM 22 , a PEC chip 23 , a QA chip connector 24 , a microcontroller 25 , and a dual motor driver chip 26 . The printhead is typically 203 mm long and has ten print chips 27 ( FIG. 13 ), each typically 21 mm long. These print chips 27 are each disposed at a slight angle to the longitudinal axis of the printhead (see FIG. 12 ), with a slight overlap between each print chip which enables continuous transmission of ink over the entire length of the array. Each print chip 27 is electronically connected to an end of one of the tape automated bond (TAB) films 28 , the other end of which is maintained in electrical contact with the undersurface of the printed circuit board 21 by means of a TAB film backing pad 29 .
[0085] The preferred print chip construction is as described in U.S. Pat. No 6,044,646 by the present applicant. Each such print chip 27 is approximately 21 mm long, less than 1 mm wide and about 0.3 mm high, and has on its lower surface thousands of MEMS inkjet nozzles 30 , shown schematically in FIGS. 9A and 9B , arranged generally in six lines—one for each ink type to be applied. Each line of nozzles may follow a staggered pattern to allow closer dot spacing. Six corresponding lines of ink passages 31 extend through from the rear of the print chip to transport ink to the rear of each nozzle. To protect the delicate nozzles on the surface of the print chip each print chip has a nozzle guard 43 , best seen in FIG. 9A , with microapertures 44 aligned with the nozzles 30 , so that the ink drops ejected at high speed from the nozzles pass through these microapertures to be deposited on the paper passing over the platen 14 .
[0086] Ink is delivered to the print chips via a distribution molding 35 and laminated stack 36 arrangement forming part of the printhead 11 . Ink from an ink cassette 37 ( FIGS. 26 and 27 ) is relayed via individual ink hoses 38 to individual ink inlet ports 34 integrally molded with a plastics duct cover 39 which forms a lid over the plastics distribution molding 35 . The distribution molding 35 includes six individual longitudinal ink ducts 40 and an air duct 41 which extend throughout the length of the array. Ink is transferred from the inlet ports 34 to respective ink ducts 40 via individual cross-flow ink channels 42 , as best seen with reference to FIG. 7 . It should be noted in this regard that although there are six ducts depicted, a different number of ducts might be provided. Six ducts are suitable for a printer capable of printing four color process (CMYK) as well as infra-red ink and fixative.
[0087] Air is delivered to the air duct 41 via an air inlet port 61 , to supply air to each print chip 27 , as described later with reference to FIGS. 6 to 8 , 20 and 21 .
[0088] Situated within a longitudinally extending stack recess 45 formed in the underside of distribution molding 35 are a number of laminated layers forming a laminated ink distribution stack 36 . The layers of the laminate are typically formed of micro-molded plastics material. The TAB film 28 extends from the undersurface of the printhead PCB 21 , around the rear of the distribution molding 35 to be received within a respective TAB film recess 46 ( FIG. 21 ), a number of which are situated along a chip housing layer 47 of the laminated stack 36 . The TAB film relays electrical signals from the printed circuit board 21 to individual print chips 27 supported by the laminated structure.
[0089] The distribution molding, laminated stack 36 and associated components are best described with reference to FIGS. 7 to 19 .
[0090] FIG. 10 depicts the distribution molding cover 39 formed as a plastics molding and including a number of positioning spigots 48 which serve to locate the upper printhead cover 49 thereon.
[0091] As shown in FIG. 7 , an ink transfer port 50 connects one of the ink ducts 39 (the fourth duct from the left) down to one of six lower ink ducts or transitional ducts 51 in the underside of the distribution molding. All of the ink ducts 40 have corresponding transfer ports 50 communicating with respective ones of the transitional ducts 51 . The transitional ducts 51 are parallel with each other but angled acutely with respect to the ink ducts 40 so as to line up with the rows of ink holes of the first layer 52 of the laminated stack 36 to be described below.
[0092] The first layer 52 incorporates twenty four individual ink holes 53 for each of ten print chips 27 . That is, where ten such print chips are provided, the first layer 52 includes two hundred and forty ink holes 53 . The first layer 52 also includes a row of air holes 54 alongside one longitudinal edge thereof.
[0093] The individual groups of twenty four ink holes 53 are formed generally in a rectangular array with aligned rows of ink holes. Each row of four ink holes is aligned with a transitional duct 51 and is parallel to a respective print chip.
[0094] The undersurface of the first layer 52 includes underside recesses 55 . Each recess 55 communicates with one of the ink holes of the two centre-most rows of four holes 53 (considered in the direction transversely across the layer 52 ). That is, holes 53 a ( FIG. 13 ) deliver ink to the right hand recess 55 a shown in FIG. 14 , whereas the holes 53 b deliver ink to the left most underside recesses 55 b shown in FIG. 14 .
[0095] The second layer 56 includes a pair of slots 57 , each receiving ink from one of the underside recesses 55 of the first layer.
[0096] The second layer 56 also includes ink holes 53 which are aligned with the outer two sets of ink holes 53 of the first layer 52 . That is, ink passing through the outer sixteen ink holes 53 of the first layer 52 for each print chip pass directly through corresponding holes 53 passing through the second layer 56 .
[0097] The underside of the second layer 56 has formed therein a number of transversely extending channels 58 to relay ink passing through ink holes 53 c and 53 d toward the centre. These channels extend to align with a pair of slots 59 formed through a third layer 60 of the laminate. It should be noted in this regard that the third layer 60 of the laminate includes four slots 59 corresponding with each print chip, with two inner slots being aligned with the pair of slots formed in the second layer 56 and outer slots between which the inner slots reside.
[0098] The third layer 60 also includes an array of air holes 54 aligned with the corresponding air hole arrays 54 provided in the first and second layers 52 and 56 .
[0099] The third layer 60 has only eight remaining ink holes 53 corresponding with each print chip. These outermost holes 53 are aligned with the outermost holes 53 provided in the first and second laminate layers. As shown in FIGS. 9A and 9B , the third layer 60 includes in its underside surface a transversely extending channel 61 corresponding to each hole 53 . These channels 61 deliver ink from the corresponding hole 53 to a position just outside the alignment of slots 59 therethrough.
[0100] As best seen in FIGS. 9A and 9B , the top three layers of the laminated stack 36 thus serve to direct the ink (shown by broken hatched lines in FIG. 9B ) from the more widely spaced ink ducts 40 of the distribution molding to slots aligned with the ink passages 31 through the upper surface of each print chip 27 .
[0101] As shown in FIG. 13 , which is a view from above the laminated stack, the slots 57 and 59 can in fact be comprised of discrete co-linear spaced slot segments.
[0102] The fourth layer 62 of the laminated stack 36 includes an array of ten chip-slots 65 each receiving the upper portion of a respective print chip 27 .
[0103] The fifth and final layer 64 also includes an array of chip-slots 65 which receive the chip and nozzle guard assembly 43 .
[0104] The TAB film 28 is sandwiched between the fourth and fifth layers 62 and 64 , one or both of which can be provided with recesses to accommodate the thickness of the TAB film.
[0105] The laminated stack is formed as a precision micro-molding, injection molded in an Acetal type material. It accommodates the array of print chips 27 with the TAB film already attached and mates with the cover molding 39 described earlier.
[0106] Rib details in the underside of the micro-molding provides support for the TAB film when they are bonded together. The TAB film forms the underside wall of the printhead module, as there is sufficient structural integrity between the pitch of the ribs to support a flexible film. The edges of the TAB film seal on the underside wall of the cover molding 39 . The chip is bonded onto one hundred micron wide ribs that run the length of the micro-molding, providing a final ink feed to the print nozzles.
[0107] The design of the micro-molding allow for a physical overlap of the print chips when they are butted in a line. Because the printhead chips now form a continuous strip with a generous tolerance, they can be adjusted digitally to produce a near perfect print pattern rather than relying on very close toleranced moldings and exotic materials to perform the same function. The pitch of the modules is typically 20.33 mm.
[0108] The individual layers of the laminated stack as well as the cover molding 39 and distribution molding can be glued or otherwise bonded together to provide a sealed unit. The ink paths can be sealed by a bonded transparent plastic film serving to indicate when inks are in the ink paths, so they can be fully capped off when the upper part of the adhesive film is folded over. Ink charging is then complete.
[0109] The four upper layers 52 , 56 , 60 , 62 of the laminated stack 36 have aligned air holes 54 which communicate with air passages 63 formed as channels formed in the bottom surface of the fourth layer 62 , as shown in FIGS. 9 b and 13 . These passages provide pressurised air to the space between the print chip surface and the nozzle guard 43 whilst the printer is in operation. Air from this pressurised zone passes through the micro-apertures 44 in the nozzle guard, thus preventing the build-up of any dust or unwanted contaminants at those apertures. This supply of pressurised air can be turned off to prevent ink drying on the nozzle surfaces during periods of non-use of the printer, control of this air supply being by means of the air valve assembly shown in FIGS. 6 to 8 , 20 and 21 .
[0110] With reference to FIGS. 6 to 8 , within the air duct 41 of the printhead there is located an air valve molding 66 formed as a channel with a series of apertures 67 in its base. The spacing of these apertures corresponds to air passages 68 formed in the base of the air duct 41 (see FIG. 6 ), the air valve molding being movable longitudinally within the air duct so that the apertures 67 can be brought into alignment with passages 68 to allow supply the pressurized air through the laminated stack to the cavity between the print chip and the nozzle guard, or moved out of alignment to close off the air supply. Compression springs 69 maintain a sealing inter-engagement of the bottom of the air valve molding 66 with the base of the air duct 41 to prevent leakage when the valve is closed.
[0111] The air valve molding 66 has a cam follower 70 extending from one end thereof, which engages an air valve cam surface 71 on an end cap 74 of the platen 14 so as to selectively move the air valve molding longitudinally within the air duct 41 according to the rotational positional of the multi-function platen 14 , which may be rotated between printing, capping and blotting positions depending on the operational status of the printer, as will be described below in more detail with reference to FIGS. 21 to 24 . When the platen 14 is in its rotational position for printing, the cam holds the air valve in its open position to supply air to the print chip surface, whereas when the platen is rotated to the non-printing position in which it caps off the micro-apertures of the nozzle guard, the cam moves the air valve molding to the valve closed position.
[0112] With reference to FIGS. 21 to 24 , the platen member 14 extends parallel to the printhead, supported by a rotary shaft 73 mounted in bearing molding 18 and rotatable by means of gear 79 (see FIG. 3 ). The shaft is provided with a right hand end cap 74 and left hand end cap 75 at respective ends, having cams 76 , 77 .
[0113] The platen member 14 has a platen surface 78 , a capping portion 80 and an exposed blotting portion 81 extending along its length, each separated by 120°. During printing, the platen member is rotated so that the platen surface 78 is positioned opposite the printhead so that the platen surface acts as a support for that portion of the paper being printed at the time. When the printer is not in use, the platen member is rotated so that the capping portion 80 contacts the bottom of the printhead, sealing in a locus surrounding the microapertures 44 . This, in combination with the closure of the air valve by means of the air valve arrangement when the platen 14 is in its capping position, maintains a closed atmosphere at the print nozzle surface. This serves to reduce evaporation of the ink solvent (usually water) and thus reduce drying of ink on the print nozzles while the printer is not in use.
[0114] The third function of the rotary platen member is as an ink blotter to receive ink from priming of the print nozzles at printer start up or maintenance operations of the printer. During this printer mode, the platen member 14 is rotated so that the exposed blotting portion 81 is located in the ink ejection path opposite the nozzle guard 43 . The exposed blotting portion 81 is an exposed part of a body of blotting material 82 inside the platen member 14 , so that the ink received on the exposed portion 81 is drawn into the body of the platen member.
[0115] Further details of the platen member construction may be seen from FIGS. 23 and 24 . The platen member consists generally of an extruded or molded hollow platen body 83 which forms the platen surface 78 and receives the shaped body of blotting material 82 of which a part projects through a longitudinal slot in the platen body to form the exposed blotting surface 81 . A flat portion 84 of the platen body 83 serves as a base for attachment of the capping member 80 , which consists of a capper housing 85 , a capper seal member 86 and a foam member 87 for contacting the nozzle guard 43 .
[0116] With reference again to FIG. 1 , each bearing molding 18 rides on a pair of vertical rails 101 . That is, the capping assembly is mounted to four vertical rails 101 enabling the assembly to move vertically. A spring 102 under either end of the capping assembly biases the assembly into a raised position, maintaining cams 76 , 77 in contact with the spacer projections 100 .
[0117] The printhead 11 is capped when not is use by the full-width capping member 80 using the elastomeric (or similar) seal 86 . In order to rotate the platen assembly 14 , the main roller drive motor is reversed. This brings a reversing gear into contact with the gear 79 on the end of the platen assembly and rotates it into one of its three functional positions, each separated by 120°.
[0118] The cams 76 , 77 on the platen end caps 74 , 75 co-operate with projections 100 on the respective printhead spacers 20 to control the spacing between the platen member and the printhead depending on the rotary position of the platen member. In this manner, the platen is moved away from the printhead during the transition between platen positions to provide sufficient clearance from the printhead and moved back to the appropriate distances for its respective paper support, capping and blotting functions.
[0119] In addition, the cam arrangement for the rotary platen provides a mechanism for fine adjustment of the distance between the platen surface and the printer nozzles by slight rotation of the platen 14 . This allows compensation of the nozzle-platen distance in response to the thickness of the paper or other material being printed, as detected by the optical paper thickness sensor arrangement illustrated in FIG. 25 .
[0120] The optical paper sensor includes an optical sensor 88 mounted on the lower surface of the PCB 21 and a sensor flag arrangement mounted on the arms 89 protruding from the distribution molding. The flag arrangement comprises a sensor flag member 90 mounted on a shaft 91 which is biased by torsion spring 92 . As paper enters the feed rollers, the lowermost portion of the flag member contacts the paper and rotates against the bias of the spring 92 by an amount dependent on the paper thickness. The optical sensor detects this movement of the flag member and the PCB responds to the detected paper thickness by causing compensatory rotation of the platen 14 to optimize the distance between the paper surface and the nozzles.
[0121] FIGS. 26 and 27 show attachment of the illustrated printhead assembly to a replaceable ink cassette 93 . Six different inks are supplied to the printhead through hoses 94 leading from an array of female ink valves 95 located inside the printer body. The replaceable cassette 93 containing a six compartment ink bladder and corresponding male valve array is inserted into the printer and mated to the valves 95 . The cassette also contains an air inlet 96 and air filter (not shown), and mates to the air intake connector 97 situated beside the ink valves, leading to the air pump 98 supplying filtered air to the printhead. A QA chip is included in the cassette. The QA chip meets with a contact 99 located between the ink valves 95 and air intake connector 96 in the printer as the cassette is inserted to provide communication to the QA chip connector 24 on the PCB. | A rotating platen for an inkjet printing device is disclosed. The platen includes an ink absorbing member disposed on part of the surface of the platen. | 1 |
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