Description:TECHNICAL FIELD

[001] The present invention relates to a receiver drier that can be integrated with a condenser (heat exchanger) for use in applications such as automotive air conditioning systems.

BACKGROUND

[002] The receiver drier of an automotive air conditioning system has three major functions. The first is to absorb any moisture content contained in the refrigerant; the second is to store a predetermined amount of the refrigerant during operation of the system, and the third is to filter out impurities from the refrigerant circulating through the receiver drier. Thus, the water absorbing matter i.e., desiccant material is placed inside a casing of predetermined volume and the impurities are caught by a filter.

[003] Recent configurations of condensers have integrated the receiver drier with one of the manifolds of the heat exchanger. The receiver drier is either made from a single circular pipe or from two semicircular header plates which are then assembled together. The inherent drawback with the latter configuration is that the number of child components is high, which results in a high cost and process cycle time. In addition, a high number of child components burdens the inventory control and increases the likelihood of incorrect assembly.

[004] Although there are some inherent advantages associated with single manifold type receiver driers, there is a growing need for reduction in overall weight and material costs, in addition to demands for further optimizations in terms of weight, cost, and manufacturability. Therefore, there exists a need in the art for a receiver drier that causes a reduction in the number of child components and thus reduces manufacturing cost and improves the manufacturability.

SUMMARY

[005] A receiver drier for integrating with a heat exchanger (condenser) is disclosed. The receiver drier comprises a cylindrical body that includes a first pipe and a second pipe; a first end cap that closes a top end of the cylindrical body; a removable second end cap (filter cap) that closes a bottom end of the cylindrical body; a first pipe comprising a filter port, a first hole, a second hole, a mating surface, a collar, and a separator slot, a second pipe that includes a top end for locking the first end cap in place, and a clad ring that acts as a brazing agent between the first pipe and the second pipe. The receiver drier is spaced by a gap from a manifold of the heat exchanger over the entire length of the second pipe, thus facilitating thermal isolation of cool refrigerant and easy removal of the filter cap. A method of manufacturing said receiver drier is also disclosed.

[006] In an embodiment, the first pipe is non-cladded. In another embodiment, the second pipe is non-cladded. In yet another embodiment, the mating surface is in the form of a saddle. In still another embodiment, the mating surface is flat with a rectangular cross section when cut in axial direction.

[007] The first end cap comprises a first surface that is mutually perpendicular with a second surface, wherein the first surface includes a flat round part, said round part being configured to include a first projection and a second projection. The first end cap is locked by either crimping a plurality of crimping tabs over the top of the first surface, or by fitting the first surface inside the second pipe and rotating the first end cap about an axis such that the first projection and the second projection fit into a plurality of axial-circumferential hybrid slots.

[008] Additional aspects, advantages, features, and objects of the present disclosure would be made apparent from the drawings and the detailed description of the illustrative embodiments, construed in conjunction with the appended claims.

[009] It will be appreciated that the features of the present disclosure are susceptible to being combined in various combinations without departing from the spirit and the scope of the disclosure, as defined by the appended claims.

BRIEF DESCRIPTION OF THE DRAWINGS

[0010] The summary above, as well as the following description of illustrative embodiments, is better understood when read in conjunction with the appended drawings. For the purpose of illustrating the present disclosure, exemplary constructions of the disclosure are shown in the drawings. However, the present disclosure is not limited to the specific details disclosed herein. Moreover, those skilled in the art will understand that the drawings are not to scale.

[0011] Figure 1 illustrates an isometric view of a heat exchanger (condenser) integrated with a receiver drier in accordance with an embodiment of the disclosure;

[0012] Figure 2 illustrates a perspective view of a mode of integrating the receiver drier with a heat exchanger (condenser) in accordance with an embodiment of the disclosure;

[0013] Figure 3 illustrates a sectional view of the receiver drier in accordance with an embodiment of the disclosure;

[0014] Figure 4 illustrates a sectional view of the first pipe in accordance with an embodiment of the disclosure;

[0015] Figure 5 illustrates an isometric view of the second pipe and the first end cap in accordance with an embodiment of the disclosure;

[0016] Figure 6 illustrates two embodiments of the mating surface

[0017] Figure 7 presents a plan view illustrating the assembly of the heat exchanger (condenser) and the receiver drier in accordance with an embodiment of the disclosure.

DETAILED DESCRIPTION

[0018] The following detailed description illustrates embodiments of the present disclosure and ways in which they can be implemented. Although some modes of carrying out the present disclosure have been disclosed, those skilled in the art would recognize that other embodiments for carrying out or practicing the present disclosure are also possible.

[0019] For the purposes of illustration, the following detailed description discloses a condenser that is used in automotive air conditioning as an example of a heat exchanger.

[0020] Figure 1 illustrates an isometric view of a condenser or heat exchanger (100) integrated with a receiver drier (101), said condenser (100) comprising a first manifold (102) that is formed from a first header plate (105; Figure 2) and a second header plate (106; Figure 2), and a second manifold (103) that is opposite to the first manifold (102), wherein the second manifold (103) is formed from a third header plate (not shown) and a fourth header plate (not shown), said first manifold (102) and said second manifold (103) being tubular, elongated, and vertically oriented. The first manifold (102) comprises a plurality of tube slots (not shown) that are aligned with a corresponding plurality of tube slots (not shown) on the second manifold (103). A plurality of multiport flat tubes extend between the plurality of tube slots on the first manifold (102) and the corresponding plurality of tube slots on the second manifold (103). A plurality of fins (not shown) is disposed between adjacent tubes. Preferably, all the components of the condenser (100) are made of aluminium and are bonded together by brazing. The condenser (100) further comprises at least two connectors (104) that serve as the point of connection of the condenser (100) into a vapour compression refrigeration system (not shown).

[0021] The connectors (104) are integrated with the first manifold (102) and/or the second manifold (103), either on the same side or opposite to each other. The receiver drier (101) is generally cylindrical, preferably shorter than the first manifold (102) and the second manifold (103), and preferably of a larger diameter than the first manifold (102) and the second manifold (103) so as to provide sufficient volume to store necessary amount of refrigerant as required. The open ends of the first manifold (102) and the second manifold (103) are sealed by a plurality of end caps (not shown) which are also preferably brazed in place.

[0022] As illustrated in Figure 2, the receiver drier (101) includes a cylindrical body (or a cylindrical member). A first end cap (110) and a second end cap (or filter cap) (129) close a top end and a bottom end respectively of the cylindrical body. The cylindrical body, along with the first end cap (110) and the second end cap (129) define an internal cavity of uniform cross section along the length to receive a desiccant bag (not shown) and a filter (not shown). The second end cap (129) is removable and is configured to include a first end (130) and a second end (131). The first end (130) comprises a plurality of external threads that fit into a first pipe (107) and the second end (131) comprises one or more radially outward facing annular grooves (132) and the filter. A plurality of annular seals (133) (preferably O-rings) is mounted on the one or more annular grooves (132) to prevent leakage of refrigerant from the receiver drier (101). After integrating the receiver drier (101) with the condenser (100), the filter and/or the desiccant bag may be introduced into and removed from the internal cavity of the receiver drier (101) through a filter port (119; Figure 4) , to allow the receiver drier (101), to be serviced if required. A clad ring (109) acts as a brazing agent between the first pipe (107) and the second pipe (108).

[0023] The construction of the receiver drier (101) will be discussed in more detail with the help of Figures 3 through 7, along with the economic and process benefits. Contrary to the prior art concept of single pipe receiver drier, where the internal cavity, the refrigerant inlet, the refrigerant outlet and the filter port are made from one cylindrical piece, the receiver drier (101) in the present disclosure is made from two cylindrical pieces, namely the first pipe (107) and a second pipe (108; Figure 2), to form a receiver drier tank (Figure 3). The first pipe (107) and the second pipe (108) are either cladded or non-cladded.

[0024] Still referring to Figure 3, the receiver drier (101) is preferably bonded to either the first manifold (102) or the second manifold (103) by furnace brazing and is spaced by a gap (111) from either the first manifold (102) or the second manifold (103) over the entire length of the second pipe (108). The gap (111) not only helps to thermally isolate relatively cool refrigerant in the receiver drier (101) from relatively hot refrigerant in either the first manifold (102) or the second manifold (103), but also facilitates the easy removal of the filter cap (129) during servicing.

[0025] Thus, this method automatically saves the machining cost which would have been incurred in creating the gap (111) over the length of receiver drier (101) if one-piece extrusion was used. Also, the weight of the receiver drier (101) is less because the thickness of the second pipe (108) is less.

[0026] As illustrated in Figure 4, the first pipe (107) of the receiver drier (101) further includes a first hole (113) and a second hole (115) for refrigerant inlet and refrigerant outlet respectively. According to the embodiment shown in Figures 1 and 2, the first hole (113) and the second hole (115) are in the form of through holes in the first pipe (107) and can be seated over a corresponding pair of aligned openings in either the first header plate (105) or the third header plate (not shown). The first hole (113) and the second hole (115) are configured such that the first hole (113) is above a separator slot (114) while the second hole (115) is adjacent to the filter port (119). The filter port (119) includes a plurality of internal threads to hold the filter cap (129).

[0027] One or more separators are fixed within the first manifold (102) and/or second manifold (103) for creating a plurality of passes of the condenser (100). The separator slot (114) is included in the first pipe (107) between the first hole (113) and the second hole (115) to avoid any interference of the one or more separators with the first pipe (107) while bonding the first pipe (107) with either the first manifold (102) or the second manifold (103).

[0028] Still referring to Figure 4, the interior of the first pipe (107) includes a first cylindrical surface (112), a second cylindrical surface (116), and a third cylindrical surface (117), wherein the first cylindrical surface (112), the second cylindrical surface (116), and the third cylindrical surface (117) are axially spaced. The first cylindrical surface includes the first hole (113), which receives the refrigerant from the first manifold (102) and acts as an inlet to the receiver drier (101). The second cylindrical surface (116), which is radially outward with respect to the first cylindrical surface (112), includes the second hole (115) at an upper end, which acts as an outlet to the receiver drier (101) and is in fluid communication with first manifold (102). The third cylindrical surface (117) includes internal threads for tightening of the filter cap (129) having external threads. The first pipe (107) further includes a mating surface (118) that sits over either the first header plate (105) or the third header plate, and a collar (134) that provides a resting surface for the second pipe (108).

[0029] Figure 5A depicts the first end cap (110) comprising a first surface (120) that is mutually perpendicular with a second surface (121). The first surface (120) includes a flat round part that is configured to include a first projection (122) and a second projection (135). The first projection (122) and the second projection (135) are either perfectly in line with each other or at an angle to each other (acute or obtuse) depending on the type of locking arrangement. As shown in figure 5B, a top end of the second pipe (108) comprises a plurality of crimping tabs (128) and a plurality of axial slots (123) to receive and lock the first end cap (110). The first end cap (110) is held in position by crimping the plurality of crimping tabs (128) over the top of the first surface (120).

[0030] In an alternate embodiment, the first end cap (110) is held in position by mechanical locking (Figure 5C). In this embodiment, the top end of the second pipe (108) comprises a plurality of axial-circumferential hybrid slots (127) (or hybrid slots). The first surface (120) is inserted into the second pipe (108) keeping both the first projection (122) and the second projection (135) aligned with the plurality of hybrid slots (127). Once the first surface (120) fits inside the second pipe (108), the first end cap (110) is rotated about an axis such that the first projection (122) and the second projection (135) fit into the plurality of hybrid slots (127).

[0031] Figure 6 depicts a top (124) and a bottom (125) of either the first header plate (105) or the third header plate, along with the mating surface (118). The mating surface (118) is either in the form of a saddle (Figure 6A) or is flat with a rectangular cross section when cut in axial direction (Figure 6B). In the case of the former (saddle), the mating surface (118) rests on an exterior surface of either the first header plate (105) or the third header plate such that an opening (not shown) in a manifold section of the penultimate pass among the plurality of passes is axially aligned with the first hole (113). The second hole (115) is axially aligned with another opening (not shown) in a manifold section of the last pass among the plurality of passes. The openings in the penultimate pass and the last pass are in the same manifold i.e. either the first manifold (102) or the second manifold (103). The saddle surface is bonded temporarily with either the first header plate (105) or the third header plate by a TIG joint. In case of the latter (flat with rectangular cross section), the mating surface comprises a blind hole (126) to facilitate the formation of a rivet joint between the first pipe (107) and either the first header plate (105) or the third header plate.

[0032] The receiver drier (101) can be mounted on the condenser (100) either in line with a core axis of the condenser (100) or at some angle to the core axis of the condenser (100). The angle 'a' shown in Figure 7 can vary from -30 degrees to +30 degrees. When the mating surface (118) is in the form of a saddle, the saddle is rotated over either the first manifold (102) or the second manifold (103) and is bonded with at the desired angle. When the mating surface (118) is flat, a flat area in either the first header plate (105) or the third header plate (not shown) is configured at the desired angle.

[0033] Another aspect of the present disclosure pertains to a method of manufacturing the receiver drier (101) and its integration with the condenser or heat exchanger (100). The method comprises the following steps:

1. Mounting the first pipe (107) over an exterior surface of either the first header plate (105) or the third header plate such that the first hole (113) and the second hole (115) in the first pipe (107) axially align with a corresponding pair of aligned openings in either the first header plate (105) or the third header plate;
2. Bonding the first pipe (107) with either the first header plate (105) or the third header plate by a TIG joint or a rivet joint;
3. Inserting the first end cap (110) into the second pipe (108);
4. Locking the first end cap (110) by either crimping the plurality crimping tabs (128) over the top of the first surface (120) or fitting the first surface (120) inside the second pipe (108) and rotating the first end cap (110) about an axis such that the first projection and the second projection fit into the plurality of hybrid slots (127);
5. Inserting the first pipe (107) into the second pipe (108); and applying the clad ring (109) over the collar (134) provided at a non-threaded end of the first pipe (107) (the clad ring (109) may be substituted with a brazing paste) ;
6. Joining the second surface (121) of the first end cap (110) with either the first header plate (105) or the third header plate, with a TIG joint or a MIG joint or a rivet joint.

[0034] Application of the clad ring (109) or the brazing paste can be avoided, if the first pipe (107) and/or the second pipe (108) are cladded.

[0035] Modifications to embodiments of the present disclosure described above are possible without deviating from the spirit and the scope of the disclosure as defined in the accompanying claims. Expressions such as “comprise” and “include”, and variations such as “comprises”, “comprising”, “includes”, and including are intended to be construed in a non-exclusive manner, namely allowing for items, components, or elements not explicitly described (or recited) also to be present. Reference to the singular is also to be construed to relate to the plural, except where explicitly stated.

Claims:We claim:
1. A receiver drier (101) for integrating with a heat exchanger (100), comprising:
a cylindrical body comprising of a first pipe (107) and a second pipe (108);
a first end cap (110) that closes a top end of the cylindrical body, said first end cap (110) comprising a first surface (120) that is mutually perpendicular with a second surface (121), wherein the first surface (120) includes a flat round part, said round part being configured to include a first projection (122) and a second projection (135);
a second end cap (129) that closes a bottom end of the cylindrical body, said second end cap (129) being removable, wherein a first end (130) of the second end cap (129) comprises a plurality of external threads that fit into a first pipe (107) and a second end (131) comprises a filter;
a clad ring (109) that acts as a brazing agent between the first pipe (107) and the second pipe (108);
the first pipe (107) comprising a filter port (119) that includes a plurality of internal threads to hold the second end cap (129); a first hole (113) that acts as an inlet to the receiver drier (101); a second hole (115) that acts as an outlet to the receiver drier (101); a mating surface (118) that sits over a header plate of the heat exchanger (100); a collar (134) that provides a resting surface for a second pipe (108), and a separator slot (114) between the first hole (113) and the second hole (115) to avoid any interference of one or more separators while bonding the first pipe (107) with a manifold of a heat exchanger (100); and
the second pipe (108) that includes a top end for locking the first end cap (110) in place,
wherein the receiver drier (101) is spaced by a gap (111) from the manifold over the entire length of the second pipe (108) to facilitate thermal isolation of cool refrigerant and easy removal of the second end cap (129).

2. A receiver drier (101) for integrating with a heat exchanger (100) as claimed in claim 1, wherein the mating surface (118) is in the form of a saddle.

3. A receiver drier (101) for integrating with a heat exchanger (100) as claimed in claim 1, wherein the mating surface (118) is flat with a rectangular cross section when cut in axial direction.

4. A receiver drier (101) for integrating with a heat exchanger (100) as claimed in claim 1, wherein the first pipe (107) is non-cladded.

5. A receiver drier (101) for integrating with a heat exchanger (100) as claimed in claim 1, wherein the second pipe (108) is non-cladded.

6. A receiver drier (101) for integrating with a heat exchanger (100) as claimed in claim 1, wherein either the first pipe (107) or the second pipe (108) is cladded; and the clad ring (109) is dispensed with.

7. A receiver drier (101) for integrating with a heat exchanger (100) as claimed in claim 1, wherein both the first pipe (107) and the second pipe (108) are cladded; and the clad ring (109) is dispensed with.

8. A receiver drier (101) for integrating with a heat exchanger (100) as claimed in claim 1, wherein the first end cap (110) is locked by crimping a plurality of crimping tabs (128) over the top of the first surface (120).

9. A receiver drier (101) for integrating with a heat exchanger (100) as claimed in claim 1, wherein the first end cap (110) is locked by fitting first surface (120) inside the second pipe (108) and rotating the first end cap (110) about an axis such that the first projection (122) and the second projection (135) fit into a plurality of axial-circumferential hybrid slots (127).

10. A receiver drier (101) for integrating with a heat exchanger (100) as claimed in claim 1, wherein the receiver drier (101) is integrated with the heat exchanger (100) by furnace brazing.

11. A receiver drier (101) for integrating with a heat exchanger (100) as claimed in claim 1, wherein the receiver drier (101) is integrated with the heat exchanger (100) by a rivet joint.

12. A receiver drier (101) for integrating with a heat exchanger (100) as claimed in claim 1, wherein the receiver drier (101) is integrated with the heat exchanger (100) by a TIG joint.

13. A receiver drier (101) for integrating with a heat exchanger (100) as claimed in claim 1, wherein the receiver drier (101) is integrated with the heat exchanger (100) by a MIG joint.

14. A receiver drier (101) for integrating with a heat exchanger (100) as claimed in claim 1, wherein the heat exchanger (100) is a multi-pass condenser.

15. A receiver drier (101) for integrating with a heat exchanger (100) as claimed in claim 1, wherein the receiver drier (101) is mounted at an angle to a core axis of the heat exchanger (100), said angle varying from -30 degrees to +30 degrees.

16. A heat exchanger (100) comprising the receiver drier (101) as claimed in claim 1 and claim 14, said multi-pass condenser comprising a first manifold (102) that is formed from a first header plate (105) and a second header plate (106); a second manifold (103) that is opposite to the first manifold (102), wherein the second manifold (103) is formed from a third header plate and a fourth header plate, said first manifold (102) and said second manifold (103) being tubular, elongated, and vertically oriented; a plurality of tube slots on the first manifold (102) that are aligned with a corresponding plurality of tube slots on the second manifold (103); a plurality of multiport flat tubes that extend between the plurality of tube slots on the first manifold (102) and the corresponding plurality of tube slots on the second manifold (103); a plurality of fins that is disposed between adjacent tubes and at least two connectors (104) that serve as the point of connection of the condenser into a vapour compression refrigeration system.

17. A method of manufacturing the receiver drier (101) as claimed in claim 1 and claim 16, said method comprising the steps of:
mounting the first pipe (107) over an exterior surface of either the first header plate (105) or the third header plate such that the first hole (113) and the second hole (115) axially align with a corresponding pair of aligned openings in either the first header plate (105) or the third header plate;
bonding the first pipe (107) with either the first header plate (105) or the third header plate, said bonding being achieved by a TIG joint or a rivet joint;
inserting the first end cap (110) into the second pipe (108) and subsequent locking, said locking being achieved by crimping the plurality of crimping tabs (128) over the top of the first surface (120) or by rotating the first end cap (110) into the plurality of hybrid slots (127) of the second pipe (108);
applying the clad ring (109) or a braze paste over the collar (134);
inserting the first pipe (107) into the second pipe (108); and
joining the second surface (121) of the first end cap (110) with either the first header plate (105) or the third header plate, said joining being achieved by a rivet joint or a TIG joint or a MIG joint.