SELF-POSITIONING ADSORBENT PACKAGE FOR AIR CONDITIONING ACCUMULATORS

Abstract: An adsorbent package (20) for use in an air conditioning accumulator (2) or receiver dryer of the type having a refrigerant fluid flow tube (9) disposed therein wherein the tube has a first end (80) having a first diameter and a lengthwise adjacent portion (82) having a second larger diameter. The adsorbent package includes a tube engaging portion (52) sized to slidably receive the first end of the tube therein and frictionally engage the lengthwise adjacent tube portion. In one embodiment, the tube engaging portion comprises an annularly shaped rigid zone (62).

Description: SELF-POSITIONING ADSORBENT PACKAGE FOR AIR CONDITIONING ACCUMULATORS BACKGROUND OF THE INVENTION The present application pertains to an adsorbent package adapted for use in air conditioning accumulators and receiver dryers of the type having a fluid flow line disposed therein that has a reduced diameter portion extending from a free end thereof and a lengthwise adjacent larger diameter portion. Adsorbent packages are typically provided in automotive accumulators and receivers to dehydrate air and refrigerants. Commonly, liquid accumulators for air conditioning systems, such as automotive air conditioning systems, employ a sealed or closed canister which provides temporary storage for the refrigerant and a lubricating fluid, and which also provides for dehydration of the refrigerant. Typically, a liquid accumulator has a permanently sealed housing which includes a baffle which separates the refrigerant into liquid and gaseous components, and also has a generally U-shaped pick-up tube or suction tube with a bight portion which has a filtered pick-up or bleed opening facing a sump area in the canister bottom. The tube also has two legs which extend upwardly toward the baffle at the top in generally, but not necessarily, parallel relationship, one end of which is open to receive an inflow of vaporized refrigerant for delivery to the suction side of a compressor by downward flow past the bottom pick-up opening. One or more desiccant packages are normally carried on or mounted on this U-shaped tube with portions extending from the filtered pick-up opening upwardly along the generally parallel portions of the tube extending from the bight portion. The desiccant package is inserted and sealed within the accumulator prior to permanent assembly of the accumulator. Accumulators of this general kind are shown in the U.S. patents of Livesay, No. 4,291,548, issued September 29, 1981, and Kisch, No. 4,496,378, issued January 29, 1985. In some cases, the adsorbent package is mounted directly to the filter. There is a need in the art to provide a stable mounting of the adsorbent package so that it will not become misaligned or dislodged during use. Such actions could block the filter or result in positioning of the adsorbent packet in the sump area of the accumulator. Also, there is a need for an adsorbent package that is easy and inexpensive to manufacture, and is easily and quickly installable in an air conditioning accumulator. SUMMARY OF THE INVENTION The above noted concerns and needs are addressed by a single, unitary adsorbent package in accordance with the invention. Briefly, the adsorbent package of the present invention comprises a single elongated pouch of filter-type material adapted for filling with desiccant or other adsorbent medium therein. An aperture is provided proximate one end of the package and is surrounded by an annularly shaped rigid zone defining a heat or ultrasonic seal of a top surface of the package with a bottom package surface to thereby form a rigid mounting zone. The package opening is force fit over a portion of one of the accumulator tubes having an enlarged diameter relative to an end diameter thereof. In normal accumulator structures, the bight tube is oriented transversely with regard to the longitudinal axis of the cylindrical housing and connects upwardly extending fluid flow tubes. A longitudinally disposed seam member is formed along the length of the top or bottom side of the adsorbent pouch. This seam includes a double fabric layer area and may be formed via conventional means such as heat sealing, ultrasonic sealing, or other electronic sealing or fusing means. This longitudinally extending zone provides a reinforced area of the pouch that is adapted for positioning adjacent an accumulator tube. The invention will be further described and illustrated in conjunction with the following detailed description and appended drawings. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is an elevation view, partially in section, of an air conditioning accumulator with a self-positioning adsorbent package of the invention installed on a refrigerant fluid flow tube therein; Fig. 2 is a top plan view of an adsorbent package in accordance with the invention; Fig. 3 is an elevation view of the adsorbent package shown in Fig. 2; Fig. 4 is a bottom plan view of the adsorbent package shown in Fig. 2; Fig. 5 is a perspective view of a U-shaped tube for an air conditioning accumulator with a self-positioning adsorbent package of the invention installed thereon; and Fig. 6 is an elevation view of the accumulator tube and adsorbent package of Fig. 5 with the adsorbent package shown partially in cross-section. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Turning first to Fig. 1, there is shown an accumulator 2 of the general type shown and described in U.S. Patent 4,474,035; the disclosure of which is incorporated by reference herein. The accumulator comprises a generally cylindrical housing 4 having a bottom wall 6 leading to a sump area 8. Fluid flow tube 9, having upstanding fluid flow tube legs 10, 12 is provided in the accumulator. A baffle 14 shields direct entry to fluid flow tube 10 as set forth in the aforementioned O35 patent. The fluid flow tube legs 10, 12, are connected via a transversely oriented bight portion 16. As per typical operation, inlet bore 100 is in communication with the outlet conduit from an evaporator or the like (not shown), with the outlet bore 102 and communicating fluid flow conduit 12 communicating with the suction or inlet side of a compressor unit (not shown). As shown, a sole adsorbent package 20 is provided toward the bottom of the accumulator 2, but does not extend into the sump area 8. In accordance with normal operation, the adsorbent package 20 comprises desiccant or the like material therein that is adapted to dehydrate the fluid medium flowing through the accumulator 2. Also, a small amount of lubricating oil or the like injected into the system is aspirated into the suction side of the compressor through a filter housing 22 depending from the bight portion 16. The filter comprises a filter medium 24. Turning now to Figs. 2-4, there is shown an adsorbent package 20 in accordance with the invention. First, looking at Fig. 2 specifically, the top side or surface 42 of the package is shown. Here, the elongated package material comprises a pouch 50 defined by transversely extending first and second end seams 46, 48, sealing the respective longitudinal ends of the pouch 50. A third transversely extending end seam 54 joins the top surface 42 to a bottom surface 66 along one edge of the package 20. A seam 44 extends longitudinally along the length of the elongated package and is slightly laterally offset from a longitudinally extending bisector line extending through the package. This seam 44 provides a double thickness of the felt-like material used to form the package 20 and therefore can be referred to as a reinforcement area. A circular aperture 60 is formed at one end of the package on the centerline of the package. A rigid heat or ultrasonically fused zone 62 surrounds the aperture 60. Optionally, the rigid zone 62 may be omitted. Tuck or fold sections 70 and 72 are disposed along a first widthwise edge of the pouch, and tuck or fold sections 74 and 76 are provided in an opposing or second widthwise edge to further define the pouch 50. The portion of the package 20, extending from the second end seam 46 to the third end seam 54 and including the aperture 60, defines a tube engaging portion 52. Although a generally circular aperture is shown in the drawings, the aperture may comprise any one of a myriad of possible cross sectional shapes such as a rectangle, a triangle, a parallelogram, a rhombus, or an oval, etc. The key criterion is that the aperture should engage the tube leg 12 in a friction fit, as will be described in further detail below. In Fig. 4 is shown a bottom side or surface 66 of the package 20. Here, aperture 60 is provided with rigid surrounding zone 62. Zone 62 provides a rigid collar which can be mounted snugly to the flow tube leg 12. The package is formed from a fibrous, air permeable material such as a synthetic felt material. Polyester felts are presently preferred but other synthetic and natural felts can of course be employed. Turning now to Figs. 5 and 6, there is shown an adsorbent package 20 in accordance with the invention installed on a fluid flow tube 9 for use in an air conditioning accumulator. The fluid flow tube 9 has a pair of generally upstanding tube legs 10 and 12. The tube leg 12 has an end portion 80 having a first diameter, and a second adjacent portion 82 having a second diameter larger than the first diameter. The adsorbent package 20 is installed on the tube 9 by sliding the tube engaging portion 52 over the end portion 80, and then further along the length of the tube leg 12 until the tube engaging portion 52 frictionally engages the adjacent portion 82. Stated differently, the tube leg 12 has a first lengthwise portion 80 with a first diameter terminating at a free end thereof, and a second lengthwise portion 82 with a second larger diameter adjacent to the first portion 80. Thus, it will be seen that the tube engaging portion 52 defines an aperture 60 that is adapted for freely sliding traversal along the first portion 80, and frictional engagement with the second portion 82. When the tube engaging portion 52 is frictionally engaged with the second tube leg portion 82, the elongated pouch 50, which is flexibly connected to the tube engaging portion 52, nestles between the two legs 10, 12 with the reinforcing seam 44 adjacent one of the legs. It is therefore apparent that, in accordance with the invention, an opening 60 is provided in the unitary package 20 that is friction fit over the tube leg 12. The opening 60 may be surrounded by an annularly shaped rigid zone 62 so as to help maintain stability of the package 20 about the tube leg 12. Presently, the diameter of the package aperture 60 is formed so that it is about 90% of the larger diameter of the tube leg 12 second or package engaging portion 82. One successfully employed package 20 has an aperture 60 diameter of about 90% of the tube leg 12 package engaging portion 82 outside diameter dimension. In one method of making the package 20 of the present invention, a tubular felted material, as previously described, is first provided. The bottom of the felt material is then sealed along one end via heat seal, or other sealing means, with ultrasound sealing being preferred, to form end seam 48 and pouch 50. Then, the pouch 50 is filled with the desired desiccant. The transverse end seam 46 is formed to seal the pouch 50. The aperture 60 is then formed by any suitable means, such as die cutting. The solid rigid zone 62 may be formed via ultrasonic sealing, if desired, either before or after the aperture 60 is formed. The top longitudinal edge of the package is then sealed by means of end seam 54. At the same time, the bottom half of the next succeeding package in the production run is sealed and the procedure repeated so that successive packages can be made. The provision of a single package for reception of desiccant therein not only reduces the number of seams and therefore potential rupture sites, but also leads to decreased production time. Additionally, due to elimination of connecting seams between packages, and the attendant reduced volume areas adjacent these seams, it is possible to place more adsorbent per unit package length into the single packages in accordance with the invention, thereby reducing the overall length of each package, which aids the process of assembling and welding the accumulator can. A typical accumulator 2, such as the one shown in Fig. 1, may be constructed by first forming a length of fluid flow tube 9 having a reduced diameter portion 80 terminating at a free end thereof, and a lengthwise adjacent, increased diameter package engaging portion 82. A bleed hole is then formed in the tube 9 at about its midpoint and a filter 22 slid over and along the tube 9 until it covers the bleed hole. The tube 9 is then bent in the shape of a U such that it has a pair of generally upstanding legs 10, 12 connected by a bight portion 16. The free end of the tube 9 having the reduced diameter portion 80 is then bent at a generally right angle to a plane containing the generally parallel legs 10, 12. An adsorbent package 20 constructed in accordance with this invention is then mounted on the tube 9 by sliding a tube engaging portion 52 over the reduced diameter end 80. With the reduced diameter end 80 received within the tube engaging portion 52, the adsorbent package 20 is oriented with its opposite end between the tube legs 10, 12 and its elongated pouch 50 directed toward the bight portion 16. The adsorbent package 20 is then slid along the tube 9 until the tube engaging portion 52 frictionally engages the adjacent larger diameter portion 82 of the tube leg 12. The adsorbent package 20 may be further forced along the tube leg 12 until the opposite end of the package 20 is resting in contact with the bight portion 16, and its reinforcing seam 44 is adjacent one of the tube legs. A baffle 14, which may be formed of molded plastic, is then fitted over the ends of the U-shaped tube 9. The U-shaped tube 9 is then inserted into an upper half 3 of the accumulator housing 4 with the reduced diameter end 80 projecting through a hole in the housing 4 to thereby form the accumulator outlet 102. The reduced diameter portion 80 of the tube 9 is attached to the housing 4 by conventional means such as welding or brazing. The accumulator upper housing 3 and U-shaped tube 9 are then inserted into the lower half 5 of the accumulator housing 4. The upper and lower halves 3, 5 of the accumulator housing 4 are pressed together and joined by welding or brazing. It will be seen that the adsorbent package of the invention is easy and inexpensive to manufacture. Further, the adsorbent package is quickly and simply installed on the accumulator fluid flow tube. Moreover, the adsorbent package is self-positioning between the tube legs where it remains firmly and reliably seated without any need for additional attachment means such as ties or clips. While the forms of apparatus herein described constitute specific embodiments of this invention, it is to be understood that the invention is not limited to these particular embodiments, and that changes may be made therein without departing from the scope of the invention which is defined in the appended claims.

Claims: CLAIMS 1. An adsorbent package for use in a canister having a tube disposed therein, said tube having an end portion having a first diameter, said tube having an adjacent portion having a second diameter larger than said first diameter, said package comprising: a tube engaging portion adapted to slidingly receive said end portion therein and to frictionally engage said adjacent portion. 2. The adsorbent package as recited in claim 1 wherein said tube engaging portion defines an opening. 3. The adsorbent package as recited in claim 1 wherein said tube engaging portion comprises an annularly shaped rigid zone. 4. The adsorbent package as recited in claim 1 further comprising: an elongated pouch extending generally longitudinally from said tube engaging portion. 5. The adsorbent package as recited in claim 2 wherein said opening has a third diameter larger than said first diameter and smaller than said second diameter. 6. The adsorbent package as recited in claim 2 wherein said opening is surrounded by an annularly shaped rigid zone. 7. In a liquid accumulator of the type housed within a generally cylindrical housing and having a pair of generally parallel spaced, upstanding fluid flow tubes disposed therein connected by a bight portion wherein one of said tubes has a first lengthwise portion with a first diameter terminating at a free end thereof > and a second lengthwise portion with a second larger diameter adjacent said first portion, an adsorbent package comprising: a tube engaging portion defining an aperture therein adapted for freely sliding traversal along said first portion and factional engagement with said second portion. 8. The adsorbent package recited in claim 7 wherein said tube engaging portion further defines an annularly shaped rigid portion surrounding said opening. 9. The adsorbent package recited in claim 7 further comprising an elongated pouch flexibly connected to said tube engaging portion and adapted to nestle between said tubes when said tube engaging portion is frictionally engaged with said second portion.

Inventors: CORRIGAN DANIEL L, PERRINE GLENN D, SULLIVAN STEVE, CORRIGAN, DANIEL, L., PERRINE, GLENN, D., SULLIVAN, STEVE
Applicants: CORRIGAN DANIEL L, HALLA CLIMATE CONTROL CANADA I, PERRINE GLENN D, STANHOPE PRODUCTS COMPANY, SULLIVAN STEVE, CORRIGAN, DANIEL, L., HALLA CLIMATE CONTROL CANADA INC., PERRINE, GLENN, D., SULLIVAN, STEVE
Application year: 1999
Main classification: F25B43
IPC codes: F25B43