Abstract:
An accumulator includes a housing having an open top end, an open bottom end, an outer wall, and an inner wall disposed within the outer wall to define an interior. The inner and outer walls are integrally interconnected by longitudinal partitions that define longitudinal channels with a downflow channel and an upflow channel positioned among the longitudinal channels. A top cover mounts to, and closes, the open top end of the housing, and has an inlet passage and an outlet passage therethrough. A refrigerant separator is positioned beneath the top cover for directing refrigerant from the inlet passage of the top cover to the interior of the housing, for venting gaseous refrigerant to the downflow passage of the housing while preventing ingress of liquid refrigerant therein, and for communicating gaseous refrigerant from the upflow passage of the housing to the outlet passage of the top cover. A cross-passage conveys gaseous refrigerant from the downflow passage of the housing to the upflow passage of the housing and includes a pickup tube for lubricating the refrigerant flowing through the cross-passage. Liquid refrigerant entering the accumulator collects in the interior of the housing and gaseous refrigerant is conveyed through an aperture in the refrigerant separator down the downflow passage, across the accumulator through the cross-passage, up the upflow passage, over the refrigerant separator, and out the outlet passage of the top cover.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to an accumulator device for use In an air-conditioning system, and more particularly to an accumulator device for use in an air-conditioning refrigeration system of a motor vehicle. 
     2. Description of the Prior Art 
     The use of accumulator devices in air-conditioning systems, particularly motor vehicle air-conditioning systems, is well known. It is also well known to use steel or aluminum in manufacturing an accumulator housing. However, it is less common to use plastic in manufacturing accumulator housings since environmental and performance requirements require use of prohibitively thick plastic walls. 
     In a typical air-conditioning system, the compressor receives a gaseous refrigerant from the evaporator and compresses the gaseous refrigerant, sending it under high pressure to the condenser as a superheated vapor. Since the high-pressure vapor delivered to a condenser is much hotter than the surrounding air, the heat of the high-pressure vapor is given off to the outside air flowing through the condenser fins, thereby cooling the refrigerant. As the gaseous refrigerant loses heat to the surrounding air, it condenses into a liquid refrigerant. The condensed liquid refrigerant then enters an orifice tube at which the pressurized liquid refrigerant transforms into a gaseous state thereby absorbing heat from warm air passing through the fins of the evaporator. 
     After the warmed liquid refrigerant changes phase to gas, it is passed from the evaporator to an accumulator. From the accumulator, the refrigerant is passed back to the compressor to start the cycle over again. However, it is very important to ensure that the refrigerant being passed back to the compressor is in a completely gaseous state. If liquid refrigerant reaches the compressor, it will clog it up. Thus, the accumulator&#39;main purpose is to assure that only gaseous refrigerant passes to the compressor. Additionally, the accumulator injects a prescribed amount of lubricating oil into the gaseous refrigerant for lubricating the compressor. Furthermore, the accumulator can be used to make sure the oil-laden gaseous refrigerant is free of particulates that might also harm the compressor. 
     Accordingly, the accumulator of an air-conditioning system can be used to accomplish five functions, it (a) completely vaporizes the refrigerant, (b) removes all water vapor, (c) traps all particulates, (d) injects a lubricant into the outgoing refrigerant vapor stream, and (e) acts as a reservoir for the refrigerant when system demand is low. Typical examples of accumulators accomplishing these functions are shown in U.S. Pat. Nos. 3,798,921; 4,111,005; 4,291,548; 4,496,378; 5,052,193; and 5,282,370. 
     Typically, a suction accumulator consists of a liquid storage vessel in which is received a generally U-shaped tube, one end of which is connected to the outlet of the storage vessel and the other end of which is opened to the interior of the vessel. As the incoming liquid refrigerant flows into the vessel, it collects in the bottom of the interior and the gaseous components of the refrigerant are forced, due to pressure in the accumulator and the vacuum created by the compressor, through the open end of the U-shaped tube and out of the accumulator. Oil for lubricating the compressor collects in the bottom of the vessel along with any liquid refrigerant. Typically, an orifice located in a bight portion of the U-shaped tube entrains, by venturi action, a metered amount of oil into the gaseous refrigerant exiting the accumulator. 
     A problem with prior art accumulators is that it is necessary to introduce some type of device, such as a refrigerant separator member, to prevent substantial amounts of liquid refrigerant from exiting the accumulator or gaining access to the open end of the U-shaped tube. Thus, it is customary to employ a refrigerant separator member somewhere proximate the open inlet end of the U-shaped tube in order to prevent the liquid from entering the exit tube of the accumulator. Typically, these refrigerant separator members have a frustoconical design that serves to deflect the liquid refrigerant back down into the bottom portion of the accumulator while allowing the gaseous refrigerant to pass by. 
     An example of such a device includes U.S. Pat. No. 4,474,035 to Amin et al. Amin et al. disclose a domed refrigerant separator located in an upper region of an accumulator housing adjacent an accumulator inlet opening. Liquid refrigerant enters the accumulator housing through the inlet opening in the top of the housing and disperses over the dome of the refrigerant separator toward the sides of the housing. This creates vertical flow of the refrigerant down the sides of the accumulator housing. The vapor component of the refrigerant collects in the upper region of the housing beneath the refrigerant separator, near the inlet end of an outlet tube. Amin et al. disclose that an inlet end of an outlet tube is located directly below the domed refrigerant separator. Amin et al. further disclose that a leg of the outlet tube is brazed or welded in a hole in the refrigerant separator as well as to the top of the accumulator housing. 
     Accordingly, traditional prior art accumulator references uniformly disclose and teach the use of a refrigerant separator member. The refrigerant separator member prevents liquid refrigerant from reaching an exit tube that is partially located within the accumulator and that is used to convey the gaseous refrigerant it to the compressor. The components, such as the exit tube and the refrigerant separator member, necessary to achieve the stated functions of an accumulator, add significantly to the cost, complexity and potential problems associated with prior art accumulators. 
     One recent approach to solving Such problems with traditional accumulators is represented in U.S. Pat. No. 5,471,854 to DeNolf. DeNolf teaches use of an accumulator that does not have a refrigerant separator member or tubes within a housing. DeNolf discloses the accumulator as having an inner housing with standoffs disposed within an outer housing thereby defining a flow path therebetwcen. A cap seals the inner and outer housings and connects the accumulator to an air-conditioning system. A refrigerant is introduced to the inner housing and flows through an aperture in the inner housing into and through the flow path down one side of the accumulator, across the bottom of the accumulator, back up an opposite side of the accumulator, and out the accumulator via a passage in the cap. 
     While the DeNolf reference represents a very significant improvement over the structure of traditional accumulators, it unfortunately involves a few drawbacks. For one, the DeNolf reference involves multiple housings that must be individually formed and further processed. Additionally, a rather rigid material, Such as aluminum, must be used in order to withstand the internal forces due to pressure within the refrigeration system and the external forces imposed upon the accumulator during assembly. Therefore, cheaper and lighter weight materials such as plastic are not generally usable with such a design. Finally, the DeNolf reference does not disclose structure for shielding the aperture in the inner housing from incoming liquid refrigerant. 
     Thus, there remains a need for an accumulator for use in an air-conditioning system of an automotive vehicle, that is adaptable to plastic materials, is more capable and more reliable in preventing liquid refrigerant from reaching the inlet line of the compressor, and wherein the accumulator does not require the use of an exit tube such as is known in the prior art. The use of plastics and the elimination of the tube and multiple housings of the prior art would result in significant cost savings in the manufacture of the accumulator. 
     SUMMARY OF THE INVENTION 
     The present invention contemplates an accumulator design for an air-conditioning system, wherein the accumulator is adaptable to use of plastics, is efficient in its operation, includes a minimum number of parts, and is less expensive to manufacture as compared to known accumulators. To reduce the number of parts and time needed to produce the accumulator, the invention further contemplates an accumulator housing wherein the tubes and multiple housings are not required. 
     An accumulator includes a housing having an open top end, an outer wall, and an inner wall disposed within the outer wall such that the inner wall defines an interior of the accumulator. The inner and outer walls are integrally interconnected by longitudinal partitions that define longitudinal channels. The longitudinal partitions further define a downflow channel and an upflow channel positioned among the longitudinal channels. The housing also has an interior defined between the open top and bottom ends, inside of the inner wall. A top cover is mounted to the open top end of the housing for closing the open top end of the housing. The top cover has an inlet passage and an outlet passage therethrough. A refrigerant separator is positioned beneath the top cover for directing refrigerant from the inlet passage of the top cover through to the interior of the housing, for preventing liquid refrigerant from entering the downflow passage of the housing, and for communicating gaseous refrigerant from the upflow passage of the housing to the outlet passage of the top cover. The refrigerant separator includes an aperture for venting gaseous refrigerant from the interior of the housing to the downflow passage of the housing. A cross-passage connects the downflow passage of the housing to the upflow passage of the housing, for conveying gaseous refrigerant therebetween. The cross-passage includes a pickup tube for lubricating gaseous refrigerant flowing through the cross-passage. Liquid refrigerant entering the accumulator collects in the interior and is vented through the aperture of the refrigerant separator, down the downflow passage of the housing, across the cross-passage, Lip the upflow passage of the housing, over the refrigerant separator, and out the outlet passage of the top cover. 
     It is an object of the present invention to provide an accumulator that overcomes some or all of the above-mentioned problems with the prior art. 
     It is another object to provide an accumulator that is capable of being automatically assembled. 
     It is yet another object of the present invention to provide an accumulator of the type described above in which a desiccant-containing member can be mounted inside of the housing. 
     It is a further object of the present invention to provide an accumulator of the type described above that can be made out of a variety of materials. 
     It is still a further object of the present invention to provide an accumulator of the type described above that can be made out of aluminum or plastic. 
     It is but a further object of the present invention to provide an accumulator of the type described above that does not incorporate a J-tube located within the housing of the accumulator. 
     It is yet another object of the present invention to provide an accumulator of the type described above that costs less to manufacture. 
     The above objects and other objects, features and advantages of the present invention are readily apparent from the following detailed description of the best mode for carrying out the invention when taken in conjunction with the accompanying drawings. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a front view of a prior art accumulator; 
     FIG. 2 is a half cross-sectional view of an accumulator according to the preferred embodiment of the present invention; 
     FIG. 2A is a top view of a bottom cover of FIG. 2; 
     FIG. 2B is another half cross-sectional view of the accumulator of FIG. 2, taken 90 degrees to the cross-section thereof; 
     FIG. 3 is partial perspective view of an alternative housing wall, having criss-cross longitudinal partitions; 
     FIG. 3A is a partial top view of an alternative housing wall, having honeycomb longitudinal partitions; 
     FIG. 3B is a partial top view of a housing wall of FIG. 2, having triangle shaped longitudinal partitions; 
     FIG. 3C is a partial top view of an alternative housing wall, having corrugated longitudinal partitions; 
     FIG. 4 is a bottom view of a top cover of the accumulator of FIG. 2; 
     FIG. 5 is a perspective view of a refrigerant separator of the accumulator of FIG. 2; 
     FIG. 6 is a top view of the housing and refrigerant separator of FIG. 2, with the top cover removed; 
     FIG. 7 is a partial cross-sectional view of a lower portion of an accumulator according to an alternative embodiment of the present invention; 
     FIG. 8 is a partial cutaway perspective view of the lower portion of an accumulator according to another alternative embodiment; 
     FIG. 8A is right side cross-sectional view of the accumulator of FIG. 8; 
     FIG. 9 is a partial cutaway perspective view of the lower portion of another alternative embodiment of the present invention; and 
     FIG. 10 is a partial cutaway perspective view of the lower portion of the preferred embodiment of the present invention. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     In general, and in view of this disclosure, those skilled in the art will appreciate that an accumulator according to the present invention may be used in other types of air-conditioning systems and at various locations within such systems. 
     Referring now specifically to the structure of the present invention as shown in the Figures, there is shown in FIG. 1 an aluminum prior art accumulator  10 P having a cylindrical housing  20 P (shown in phantom line), a top cover  60 P, a refrigerant separator  70 P, and a J-tube  96 P with a desiccant pack  12 P strapped thereto. The accumulator  10 P is not easily assembled automatically since the J-tube  96 P must be bent and positioned in place to the top cover  60 P by hand. Additionally, the desiccant pack  12 P must be strapped in place to the J-tube  96 P by hand. 
     As shown in FIG. 2, an accumulator  10  according to the preferred embodiment of the present invention includes a housing  20  preferably in the form of a hollow cylinder and having an open top end  22  and an open bottom end  24 . The housing  20  also has an outer wall  26  and an inner wall  28  disposed within the outer wall  26 . At the open bottom end  24 , a U-shaped canopy  30  spans radially across opposite sides of the inner wall  28 . Reference to FIG. 10 will reveal the true shape of the U-shaped canopy  30 . 
     As shown in FIG. 3, the inner wall  28  is integrally interconnected to the outer wall  26  by integral longitudinal partitions  32  that define longitudinal passages  33 . Such matrix-walled structure is common in the manufacture of plastic well pipe and plastic underground pipelines, as evidenced by U.S. Pat. Nos. 4,215,727 and 4,341,392. Alternatively, integral longitudinal partitions  32 A,  32 B,  32 C may take the form of honeycomb, opposed triangle, or corrugated structure as shown in FIGS. 3A,  3 B, and  3 C respectively. It is contemplated that other easily formed structures could be substituted for the examples shown in FIGS. 3 through 3C. 
     Referring again to FIG. 2, the inner and outer walls  28  and  26  extend longitudinally between the open top and bottom ends  22  and  24 . In addition, a downflow passage  34  and an upflow passage  36  are disposed between the inner and outer walls  28  and  26 . It is possible to construct the housing  20  out of any material suitable for use as an accumulator device of an air-conditioning system, such as ferrous and non-ferrous metals or composites. The housing  20  according to the present invention, however, is preferably manufactured from a polymeric material having sufficient strength to withstand the forces experienced during operation. The housing  20  may be manufactured using any known method but is preferably extruded, injection molded, or made by a combination of the two. Accordingly, the U-shaped canopy  30  may be overmolded separately into an extrusion to form the housing  20 . In other words, an extruded portion of the housing  20  may be cut to length from a continuous extrusion and be placed in a molding press where the U-shaped canopy  30  is then molded in position to bottom of the housing  20 , as is known in the art of plastics molding. 
     Still referring to FIG. 2, a bottom cover  40  is preferably molded from plastic and is used to close the open bottom end  24  of the housing  20 . The bottom cover  40  includes a pickup tube  46  molded therein. As shown in FIG. 2A, the bottom cover  40  includes an integral U-shaped trough  42  that is molded radially across the bottom cover  40 . The pickup tube  46  is mounted transverse to and through the U-shaped trough  42 . The pickup tube  46  has a hole  48  that communicates with the inside of the U-shaped trough  42 , and further has opposite open ends  50  that communicate with the hole  48 . Each opposite open end  50  of the pickup tube  46  opens into separate reservoirs  44  of the bottom cover  40 . The U-shaped trough  42  sealingly fits within the U-shaped canopy  30  of the housing  20  to form a cross-passage  52 . 
     The cross-passage  52 , as shown in FIG. 2, communicates the downflow passage  34  with the upflow passage  36 . Also shown in FIG. 10, the bottom cover  40  includes the U-shaped trough  42  that fits within the U-shaped canopy  30  of the housing  20  to produce a refrigerant-tight seal and define the cross-passage  52 . It is possible to connect the U-shaped trough  42  and the U-shaped canopy  30  in any manner as long as the cross-passage  52  thus formed functions to convey gaseous refrigerant across the accumulator  10  between the bottom cover  40  and housing  20 , while preventing liquid refrigerant from entering the cross-passage  52 . In view of this disclosure, those skilled in the art will appreciate that the bottom cover  40  could be threaded to the housing  20 , or snapped to the housing  20  with integral fasteners. Preferably, however, the bottom cover  40  is bonded or ultrasonically welded to the housing  20 . 
     Referring again to FIG. 2, a top cover  60  closes the open top end  22  of the housing  20  and a refrigerant separator  70  is mounted therebetween. An interior  38  of the accumulator  10 , having a circular cross section, is defined inside the inner, wall  28  between the top and bottom covers  60  and  40 , and beneath the refrigerant separator  70 . The top cover  60  includes an inlet passage  62  for introducing refrigerant to an inlet portion  72  of the refrigerant separator  70  and into the interior  38  of the accumulator  10 . As shown in FIG. 4, the top cover  60  includes an arcuate undersurface  64  and has an outlet passage  66  positioned next to the inlet passage  62 . Referring again to FIG. 2, the outlet passage  66  communicates with the upflow passage  36  via a path defined between a gas outlet portion  74  of the refrigerant separator  70  and the top cover  60 . In view of this disclosure, those skilled in the art will appreciate that the top cover  60  could be snapped to the housing  20  with integral fasteners, or could be ultrasonically welded to the housing  20 . Preferably, however, the top cover  60  is threaded to the housing  20 , to allow the accumulator  10  to be readily serviceable. 
     As shown in FIG. 5, the refrigerant separator  70  is preferably molded from plastic, is convex in shape, and promotes separation of the refrigerant entering the accumulator  10  into separate liquid and gaseous components. The refrigerant separator  70  includes the liquid inlet portion  72 , a gas aperture portion  76 , and the gas outlet portion  74 , that are all separated from one another by partitions  78 . As shown in FIG. 2, a top surface  80  of the partitions  78  seals against the arcuate undersurface  64  of the top cover  60  so as to fluidly isolate the inlet portion  72 , gas aperture portion  76 , and gas outlet portion  74 . 
     Still referring to FIG. 2, a desiccant pack  90  of any known shape and size is inserted in the interior  38  of the housing  20 . The desiccant pack  90  is provided to help remove any moisture from the refrigerant that may be harmful to the compressor. Preferably, the desiccant pack  90  is a puck-shaped member that is easily inserted into the interior  38  of the housing  20 . In view of this disclosure, those skilled in the art will appreciate that the desiccant contained within the accumulator  10  could include either a pellet or a porous cake form of desiccant, or any other type of desiccant suitable for use in an accumulator device. Preferably, the desiccant pack  90  is positioned within the housing  20  above the ambient liquid refrigerant level. This will assure that the desiccant will be more efficiently used, as it will not be submerged within the liquid refrigerant and lubricating oil. Any known method of positioning the desiccant pack  90  within the housing  20  may be used, such as an interference fit as shown in FIG. 2, or using suitable locating features. 
     An accumulator  310  according to an alternative embodiment of the present invention is shown in FIG.  7 . Here, the gaseous refrigerant flows from a downflow passage  334  of a housing  320  into a cross-passage  352  that is defined by a bottom surface  330 A of a cup  330  and an upper surface  354  of a bottom cover  340 . The cup  330  is preferably molded from plastic and is pressed into an interior  338  of the housing  320  to form a fluid-tight fit with the housing  320 . A hole  330 B is formed into the bottom surface  330 A of the cup  330  to allow oil to be metered into the crosspassage  352 . 
     A method of manufacturing the accumulator  310  according to the alternative embodiment of FIG. 7 involves the following steps. The housing  320 , having the top end  322  and bottom end  324 , is preferably parted from a continuous extrusion having a matrix cross section as described previously. The top cover (not shown), refrigerant separator (not shown), cup  330 , and bottom cover  340  are molded, preferably using an injection molding process. The bottom cover  340  is then secured to the bottom end  324  of the housing  320 . The cup  330  is pressed into the top end  322  of the housing  320  and is located inside of the housing  320  until it bottoms out against the bottom cover  340 . The desiccant pack (not shown) is provided and assembled into the housing  320 . The refrigerant separator (not shown) is installed to the top end  322  of the housing  320  and the top cover (not shown) is fastened to the top end  322  of the housing  320  over the refrigerant separator. 
     A method of manufacturing the accumulator  10  according to the preferred embodiment of FIG. 2 involves the following steps. Molding the housing  20  having the top end  22  and bottom end  24 , and similarly molding the top cover  60 , refrigerant separator  70 , and bottom cover  40 . The bottom cover  40  is secured to the bottom end  24  of the housing  20 . A desiccant pack  90  is provided and is assembled into the housing  20 . The refrigerant separator  70  is installed to the top end  22  of the housing  20 , and the top cover  40  is fastened to the top end  22  of the housing  20 . 
     Referring now to the operation of the present invention and specifically to FIG. 2B, the accumulator  10  performs as follows. Liquid refrigerant enters the accumulator  10  through the inlet passage  62  of the top cover  60  and flows over the liquid inlet portion  72  of the refrigerant separator  70 . Arrows  72 A in FIG. 6 indicate the flow path of the refrigerant over the liquid inlet portion  72  of the refrigerant separator  70 . As indicated in FIGS. 2B and 6, the refrigerant impinges upon the liquid inlet portion  72  and flows radially outward until it reaches a gap  82  defined between the periphery of the liquid inlet portion  72  and the inner wall  28  of the housing  20 . At that point the refrigerant flows downward into the housing  20 . 
     Referring again to FIG. 2, the refrigerant flows down into the interior  38  of the housing  20  and through the desiccant pack  90 , as indicated by arrows  38 D. to The desiccant pack  90  thereby removes moisture from the liquid refrigerant to protect the compressor. Thus, the gaseous refrigerant is collected in the interior  38  of the accumulator  10  and is forced, under pressure resident in the air-conditioning system, to flow through the gas aperture portion  76  of the refrigerant separator  70 , as indicated by arrows  38 U. The gascous refrigerant is forced to flow into and down the downflow passage  34  of the housing  20 , as indicated by arrow  34 D. FIG. 6 illustrates the gaseous refrigerant, as indicated by the arrows  38 U, flowing up through the gas aperture portion  76  outwardly across the refrigerant separator  70  and down into the downflow passage  34  of the housing  20 . The partition  78  separates the gas aperture portion  76  from the inlet portion  72 . 
     Referring again to FIG. 2, the refrigerant flows from the downflow passage  34  into the cross-passage  52 , as indicated by arrow  52 A. As shown in partial cross-sectional view in FIG. 10, the U-shaped trough  42  of the bottom cover  40  fits into the U-shaped canopy  30  of the housing  20  to define the cross-passage  52 . The cross-passage  52  is isolated from the rest of the interior  38  of the accumulator  10  except via the hole  48  in the pick-up tube  46 . Oil resident in the refrigerant flowing through the air-conditioning system will collect in the bottom of the accumulator  10 . Vacuum is pulled through the pick-up tube  46  as gaseous refrigerant flows through the cross-passage  52  and past the pick-up tube  46 . This induces the oil that is resident at the bottom of the interior  38  of the housing  20  to be metered to the center of the pickup tube  46  through the open ends  50  of the pick-up tube and out the hole  48  into the gaseous refrigerant. A metered amount of oil is pulled through the pickup tube  46  so that a controlled amount of oil is returned to the gaseous circuit of the air-conditioning system. This oil helps to keep the compressor lubricated to ensure proper working order. 
     FIGS. 8,  8 A, and  9  illustrate alternative embodiments of pick-up tubes  146  and  246  mounted within a bottom cover  140  and  240 , respectively. FIG. 8 shows a partial view of an accumulator  110  having a pick-up tube  146  molded into a U-shaped trough  142  of the bottom cover  140  so as to communicate a cross-passage  152  with an interior  138  of the accumulator  110 . The bottom cover  140  includes a raised and sloped surface  141  for draining oil to the side of the accumulator  110  where the pick-up tube  146  is located. The pick-up tube is located to position an open end  150  at the bottom of the inside of the accumulator  110  where the lubricant settles out of the refrigerant. FIG. 9 illustrates a partial view of an accumulator  210  having a macaroni-shaped pick-up tube  246  having open ends  250  that communicate with an integral stem portion  248  that communicates with a cross-passage  252 . 
     Referring again to FIG. 2, the gaseous refrigerant flows from the cross-passage  52  into and up the upflow passage  36 , as indicated by arrow  36 U. Finally, the gaseous refrigerant exits the accumulator  10  by flowing from the upflow passage  36 , across the outlet portion  74  of the refrigerant separator  70  and out the outlet passage  66  of the top cover  60 . 
     From the above, it can be appreciated that a significant advantage of the present invention is that an accumulator can be manufactured from lightweight, inexpensive plastic components that may be automatically assembled in order to reduce weight and cost. 
     Another advantage is that in one alternative embodiment the housing may be extruded for purposes of significant cost savings. 
     Yet another advantage is that the accumulator components may have integral features such as threads and other fastening devices molded integrally therein without any need for machining. 
     Still another advantage is that the accumulator is rebuildable, involving removal of the top cover followed by removal of the spent or contaminated desiccant pack, followed by cleaning of the interior, followed by insertion of a new desiccant pack, and fastening of the top cover back on the housing. 
     An additional advantage is that the matrix wall structure of the housing lends itself to improved strength characteristics and improved insulating properties of the accumulator for better overall system efficiency. 
     While the present invention has been described in terms of a preferred embodiment, it is apparent that other forms could be adopted by one skilled in the art. The accumulator according to the present invention allows for significant changes in the dimensions of the accumulator such that it is possible to have accumulators of different dimensions, shapes, and sizes utilizing the invention described herein. Additionally, it should be obvious that the exterior structure can be modified by one skilled in the art without departing from the invention as disclosed herein. Moreover, a closed bottom housing could be used, and the refrigerant separator could be made integral with the top cover for reduced part count. It would also be possible to reverse the structure of the accumulator to achieve the same flow path described herein. Accordingly, the scope of the present invention is to be limited only by the following claims.