EP1853859A2

EP1853859A2 - Coolant collector comprising a filter/dryer unit

Info

Publication number: EP1853859A2
Application number: EP06723160A
Authority: EP
Inventors: Peter Klug
Original assignee: Eaton Fluid Power GmbH
Current assignee: Eaton Fluid Power GmbH
Priority date: 2005-03-01
Filing date: 2006-03-01
Publication date: 2007-11-14
Anticipated expiration: 2026-03-01
Also published as: WO2006092285A3; CN100538215C; CN101166942A; DE102005009191B3; WO2006092285A2; ATE437345T1; ES2329169T3; EP1853859B1; US20080282727A1; DE502006004303D1

Abstract

Disclosed is a coolant collector ( 1 ) comprising a filter/dryer unit ( 10 ) and an elongate, vertically oriented interior space which is subdivided into an upper area ( 38 ) and a lower area ( 39 ) by means of the filter/dryer unit ( 10 ). A flowing coolant is delivered to the filter/dryer unit ( 10 ) via a pipe ( 7 ). The outlet windows of the filter/dryer unit ( 10 ) are located on the outer circumference thereof which delimits a relatively narrow gap along with the wall ( 3 ) of the receptacle ( 2 ) of the coolant collector ( 1 ). Liquid components drip downwards and accumulate below the filter/dryer unit while gaseous components accumulate primarily above the filter/dryer unit ( 10 ).

Description

February 28, 2005 EAPL P 057 abet

05-BAD-905

Eaton Fluid Power GmbH, Dr. med. -Reckeweg-Str. 1, 76532 Baden-Baden

Refrigerant collector with Pilter / dryer Einhei ^'t

The invention relates to a refrigerant collector with filter / dryer unit for refrigeration systems. The refrigerant collector according to the invention is particularly suitable for motor vehicle air conditioning systems and in particular for those which are operated with carbon dioxide as the refrigerant.

Refrigerant collectors are usually traversed by refrigerant, while holding a supply of refrigerant. This buffers lower refrigerant losses of the chiller and different. Operating conditions of the same. Therefore, there is usually a certain supply of liquid sigen refrigerant in the refrigerant collector. The refrigerant must be dry. If ice forms in unfavorable places in the chiller, this can lead to malfunctions and damage to the chiller. This is why refrigeration plants usually have dryers. These are, for example tubular storage vessels, in which a water-absorbing material such as granules is arranged. This is flowed through by the refrigerant. It is important to ensure a sufficiently intimate contact between the refrigerant and the dryer material.

In particular, the compressors of CO ₂ refrigerating machines but also the compressors of other refrigerating machines are relatively sensitive to aspirated fluid droplets and in particular solid particles. It is therefore desirable to ensure that the refrigerant flow sucked in by the compressors contains in particular no solid particles.

On this basis, it is an object of the invention to provide a unit which solves at least some of the above problems in a technically simple and reliable manner.

This object is achieved with the refrigerant collector with integrated filter / dryer unit according to claim 1:

The refrigerant collector according to the invention is based on a pressure-resistant, upright vessel with wall, bottom and upper end, so that a closed interior is enclosed. A first tube leads into the interior and a second tube leads out of the interior. In the interior of a filter / dryer unit is arranged, which is fed by the tube leading into the interior. The filter / dryer unit is doing about in her Center supplied with refrigerant. The filter / dryer unit has at least one, but preferably a plurality of large-area outlets, whose cross section exceeds the cross section of the feeding pipe. The outlets open into the interior of the container, where both oil and liquid refrigerant can collect. The tube leading out of the interior space has an upper open end, which is preferably arranged above the filter / dryer unit. It leads from this point out of the interior. It is preferably U-shaped around the

Filter / dryer unit guided around, wherein a lower pipe bend of the pipe leading out of the interior immediately above the bottom of the vessel. In this area, a suction opening is preferably arranged. The pipe bend undercuts an oil level, which is located in the

Forming vessel. As a result, the refrigerant flow leaving the vessel can be metered in via the intake opening and carried along with it. This is desired for lubrication of the connected compressors.

Between the oil level and the filter / dryer unit a partial volume of the interior is limited, in which refrigerant can be present in the liquid phase. The amount of liquid refrigerant may vary depending on the conditions of use of the refrigerator. However, the filter / dryer unit separates the refrigerant level from the upwardly towering open tube end of the tube leading out of the inner space, so that no splashes of refrigerant can get into the open tube end, even if the refrigerant collector when installed in a motor vehicle shaken during heavy driving maneuvers or bumpy roads.

In a preferred embodiment, the wall of the vessel of the refrigerant collector is cylindrical, whereas the bottom of the vessel is rounded. The latter has the advantage that even with small amounts of oil, a sufficiently high oil level can be achieved in order to provide the refrigerant flow with oil. In addition, the vessel shape is particularly pressure-resistant in this way.

The upper end of the vessel is preferably formed flat or slightly rounded, the two tubes side by side into the vessel as well as lead out of this. Thus, above the filter / dryer unit, an approximately cylindrical vapor dome is formed, in which refrigerant is predominantly in the gaseous phase and can be withdrawn well. The connection of the two side by side preferably parallel to each other oriented tubes is also easy and clear.

Preferably, the filter / dryer unit occupies the entire cross section of the interior in such a way that it defines only a relatively narrow annular gap with the wall of the vessel. Out of this annular gap, refrigerant with a relatively low flow rate enters the upper area serving as vapor dome. Sloshing movements of the refrigerant level located below the filter / dryer unit hardly lead to liquid refrigerant reaching the area above the filter / dryer unit. This is certainly not the case in view of the preferred height (axial extent) of the filter / dryer unit, which is preferably larger than the diameter thereof.

From the annular gap liquid refrigerant and oil drip down and collect below the filter / dryer unit. Liquid CO2 floats. while on the oil level. In principle, it is possible for the oil collecting under the filter / dryer unit to be drawn off from the vessel via capillaries or separate lines and to be added to the oil stream. The pipe leading out of the interior can thus lead directly out of the upper steam dome area to the outside. As a simple and robust solution, however, it is preferred to guide the pipe leading out of the interior space both descending and ascending between the wall and the filter / dryer unit and thus to guide the refrigerant sucked up in the steam dome area through the lower pipe bend, where it is is mixed with oil.

The filter / dryer unit preferably has a housing with a flat upper side and an approximately cylindrical outer circumference. This effectively separates the liquid refrigerant phase from the vapor refrigerant phase. In addition, it offers a sufficiently large interior to accommodate a large desiccant portion.

It has proven to be very advantageous to provide the filter / dryer unit with a conical bottom. The tip of the bottom is preferably located centrally in the housing approximately below the feeding tube. The cone angle is relatively large and is preferably between 120 ° and 170 °. This shape of the bottom has proven to be advantageous both in terms of the forming flow pattern as well as purely practical because it allows a good compacting of the dryer granules when closing the filter / dryer unit. This is especially true when the bottom is inserted into the housing of the filter / dryer unit from below and then fixed, for example, by locking means. The dry granules are flowed through substantially radially, wherein the flow rate is low and decreases towards the outside. This will be one 006/001862

intimate contact between dry granulate and refrigerant fluid. The low flow rate in the housing of the filter / dryer unit results in a low pressure drop across the refrigerant collector.

Spherical granules are preferably used as dry granules, which provides optimum contact between the refrigerant and the dry granules.

On the inlet side, the filter / dryer unit is provided with an inlet basket having at its periphery and at its bottom outlet openings, e.g. Has holes and slots. The inlet basket allows the introduction of refrigerant fluid into the dry granulate with low pressure drop. At the outlet openings of the housing of the filter / dryer unit, a fine filter is preferably arranged. This is e.g. formed by a fine stainless steel mesh, a stainless steel felt or the like. The mesh size is preferably in the range of 30 microns to 60 microns.

The conical bottom is a prerequisite that leads to a good separation of gaseous and liquid phase. The accumulation of liquid refrigerant and / or oil in the filter / dryer unit is safely avoided. Thus, the dryer granules themselves are kept free of liquids, so that its effectiveness is not affected by oil or liquid refrigerant.

The outlet windows occupy almost the entire outer circumference of the housing of the filter / dryer unit. This further leads to an efficient use of the desiccant through slow flow and safe discharge of liquid refrigerant and oil from the housing of the filter / dryer unit. Further details of advantageous embodiments of the invention are the subject of the drawing, the description or claims.

In the drawing, an embodiment of the invention is illustrated. Show it:

Figure 1 shows the refrigerant collector in a perspective

Overall view ,

FIG. 2 shows the refrigerant collector according to FIG. 1 in a perspective, vertically sectioned illustration,

3 shows the refrigerant collector of Figure 2 in a vertical sectioned view with additional

Sectional view of its filter / dryer unit,

Figure 4 shows the filter / dryer unit of the refrigerant collector according to Figures 2 and 3 in a vertical sectional view and

Figure 5 shows the refrigerant collector of Figure 1 in a partial sectional view.

1 shows a refrigerant collector 1 is illustrated, the outer vessel 2 is formed by an aluminum bottle. This has a cylindrical wall 3 with a substantially flat upper termination 4 and a e.g. spherical convex ground 5. The bottom 5 may be provided with an opening into which a burst plug 6 is screwed. The vessel 2 is closed on all sides to the outside. It may be welded together from two or more parts, the welds are not illustrated in Figure 1. Preferably, the vessel 2 is without

Welding and soldering seams, i. formed without welding and soldering. For this purpose, a hollow cylindrical blank is first produced which already contains the upper end 4. When all the later explained internals are placed in the vessel 2, the latter is closed to its bottom 5 in a roll forming process or in an alternative forming process to the extent that only the opening to be closed by the stopper 6 remains. This manufacturing method makes it possible to produce the vessel 2 with relatively low wall thicknesses even if it has to be designed for very high bursting pressures of, for example, more than 200 bar. Otherwise occurring during welding and soldering, occurring due to the temperature stress structural changes of the material are excluded.

Through the conclusion 4 lead two tubes 7, 8 in the area enclosed by the vessel 2, from Figure 2 apparent interior 9 in and out of this. The ends of the tubes I ₁ 8 enforce the conclusion 4 while parallel to each other. The pipe 7 forms the input-side line for introducing refrigerant into the refrigerant collector 1. It leads to a filter / Troσkner unit 10, which is housed in the inner space 9 in a separate housing 11. The arranged in the interior 9 end 12 of the tube 7 leads to a πύttigen terminal, which is on the housing 11, that is, in fact / on its preferably flat top 13 is arranged. The housing 11 also has an approximately cylindrical outer circumference 14, whose diameter is slightly smaller than the inner diameter of the wall 3, so that a slot is formed between the two. To set this defined and to center the housing 11 in the vessel 2, the outer periphery 14 is provided with radially outwardly projecting Abstandshalternasen 15, which are preferably in the form of elongated vertical, ie axially oriented ribs 16, 17, 18 are formed. On the outer circumference 14 also outlet windows 19, 20, 21, 22, 23 (see Figures 2 and 3) are formed, the apparent from Figure 3 interior 24 of the housing 11 on its entire circumferential surface to the inner space 9 of the vessel 3 out to open. The outlet windows 19 to 23 are separated from each other only by narrow webs, which connect the upper end plate located on the upper side 13 with a lower ring 25 which holds a bottom 26 inserted into the housing 11. The outlet windows 19 to 23 may be provided with a plastic grid, which supports the filter used later explained and protects against manual damage, in particular during assembly.

The bottom 26 is preferably, like the rest of the housing 11, made of plastic. It has an upwardly extending from an annular rim 27 conical bottom portion 28 which has a cone angle of preferably about 130 ° to 150 °. The bottom 26 is preferably not further illustrated locking means with the ring

25 connected. Its outer edge 29 terminates with the upper edge of the ring 25 or is located just above it. The outlet windows 19 to 23 are closed by a fine mesh filter. This may be formed for example by a stainless steel mesh, a stainless steel felt or the like. The mesh size is preferably in the range between see 30 microns and 60 microns.

In the interior 24 of the housing 11, an inlet basket 31 is arranged, which is preferably integrally connected to the upper end plate of the housing 11. The inlet basket 31 has, for example, a cylindrical shape. At its periphery it is provided with slots 32. In its bottom openings 33 are formed. The slits 32 and openings 33 preferably have a width of not more than 0.8 mm. In any case, however, the width of the slots 32 and openings 33 is less than the grain size of a dry granulate that fills the interior 24. This granulate serves for water absorption.

The housing 11 has groove-like, preferably approximately cylindrical shell-shaped recesses on diametrically opposite or otherwise positioned to each other points, through which the tube 8 extends. It goes from an open, located above the filter / dryer unit 10 end vertically down to the bottom 5 of the vessel 2. The corresponding straight pipe section 34 then passes below the filter / dryer unit 10 in a pipe bend 35, of which starting with a further pipe section 36 again on the filter / dryer unit 10 over to the conclusion 4 and through this leads to the outside. The pipe bend 35 runs just above the bottom 5, as can be seen in particular from FIG. At its lowest point, at which the pipe bend 35 is closest to the bottom 5, the pipe bend is provided with a suction bore 37. These has a small diameter and serves to add oil to the refrigerant flowing in the pipe bend 35.

The refrigerant collector 1 described so far operates as follows:

In operation, the vessel 2 is arranged vertically, i. its tubes 7, 8 lead substantially vertically into the interior 9. The central axis of the cylindrical wall is oriented vertically. Through the pipe 7 refrigerant flows from a chiller first into the filter / dryer unit, which divides the interior 9 into an upper region 38, which serves as a steam dome, and a lower region 39, which serves as a liquid collector. As a rule, the refrigerant is a three-phase mixture consisting of gaseous refrigerant, liquid refrigerant and liquid oil particles. It initially enters the inlet basket 31 and leaves it through the slots 32 and the openings 33, through which it passes into the dense packing of the preferably spherical dryer body. In this case, flows through the openings 32 of the bottom portion 28, which redirects the flow radially outward. This results in a relatively uniform, slow flow through the held in the interior 24 dryer pack. Liquid ingredients, i. Liquid refrigerant and oil reach the bottom portion 28 and run on this outward. They exit the filter / dryer unit 10 through the outlet windows 19 to 23 and then run down the ring 25 in the subspace formed by the area 39. By contrast, gaseous refrigerant collects predominantly in the region 38 of the interior 9, from which they are drawn off via the pipe 8.

Under the filter / dryer unit 10 forms a liquid reservoir consisting of oil and liquid refrigerant tel. Because of the different densities, both divorced from each other. This is especially true when CO _{2 is} used as the refrigerant. An oil volume 40 with an oil level 41, on which a liquid refrigerant volume 42 rests with a refrigerant level 43, is formed above the bottom 5. The oil level 41 is at least above the suction bore 37. The refrigerant level 43 is at least below the edge 29, but preferably below the ring 25th

The vaporous refrigerant present in the region 38 flows through the pipe section 34 and the pipe bend 35, taking along oil via the suction bore 37. The suction bore 37 may also be considered a drainage bore, which limits the entry of oil into the tube 8 to a desired low level. If necessary, several such holes can be provided. In addition, a filter, for example in the form of a metal mesh, metal felt or the like may be arranged between the pipe bend 35 and the bursting plug 6.

The filter / dryer unit 10 causes not only a drying of the refrigerant but at the same time such an effective subdivision of the interior 9 that no splashes of the optionally boiling or sloshing by external movement surface of the refrigerant volume 42 into the open end of the pipe section 34. It is created in this way a simple, combined refrigerant collector with integrated filter / dryer unit 10.

A refrigerant receiver 1 with filter / dryer unit 10 has an elongate, vertically oriented interior, which is subdivided by the filter / dryer unit 10 into an upper area 38 and a lower area 39. Inflowing refrigerant is through a pipe 7 of the Filter / dryer unit 10 which has its outlet window at its outer periphery, which defines a relatively narrow gap with the wall 3 of the vessel 2 of the refrigerant collector 1. Liquid components drip down and collect below the filter / dryer unit. Gaseous components accumulate predominantly above the filter / dryer unit 10.

Claims

Claims:

1. Refrigerant collector (1)

with a pressure-resistant, upright vessel (2), which has a wall (3), a bottom (5) and an upper end (6), which enclose an internal space (9),

with a pipe (7) leading into the interior space (9), which has an end (12) arranged in the interior space (9)

with a filter / dryer unit (10), which is connected to the in the interior (9) lying end (12) of the leading into the interior (9) pipe (7) and arranged at a distance above the bottom (5) .

with a pipe (8) leading out of the interior space (9) and having an open end arranged in the interior space (9) above the filter / dryer unit (10).

2. Refrigerant collector according to claim 1, characterized in that the out of the interior (9) leading out tube (8) starting from its open end to a at the bottom (5) arranged pipe bend (35) and from this rising from the Vessel (2) extends out, wherein in the pipe bend (35) at least one suction opening (37) is arranged.

3. Refrigerant collector according to claim 1, characterized in that the wall (3) of the vessel (2) is cylindrical. 006/001862

4. Refrigerant collector according to claim 1, characterized in that the bottom (5) of the vessel (2) is rounded.

5. A refrigerant collector according to claim 1, characterized in that the upper end (4) of the vessel (2) is formed flat and both tubes (7, 8) side by side in the vessel (2) into or out of this out.

6. Refrigerant collector according to claim 1, characterized in that the filter / dryer unit (10) occupies the entire cross section of the interior (9) and defines an annular gap with the wall.

7. Refrigerant collector according to claim 1, characterized in that the out of the interior (9) leading out tube (8) both descending and ascending between see the wall (3) and the filter / dryer unit (10) is passed.

8. A refrigerant collector according to claim 1, characterized in that the filter / dryer unit (10) has a housing (11) with a flat top (13) and an approximately cylindrical outer periphery (14), from which spacer lugs (15) extend the wall to support this.

9. A refrigerant collector according to claim 1, characterized in that the filter / dryer unit (10) has a conical bottom (26).

10. A refrigerant collector according to claim 1, characterized in that the filter / dryer unit (10) on its upper side (13) has a central port which is connected to the in the interior (24) leading tube (7).

11. A refrigerant collector according to claim 10, characterized in that the filter / dryer unit (10) encloses a receiving space (24) in which an immediately adjacent to the central terminal inlet basket (31) with inlet openings (32, 33) is arranged

12. A refrigerant collector according to claim 11, characterized in that the filter / dryer unit (10) the inlet openings as holes (33) or slots (32) are formed whose width is not greater than the grain size of a dryer granules.

13. A refrigerant collector according to claim 1, characterized in that the filter / dryer unit (10) on its outer circumference outlet window (19, 20, 21, 22, 23).

14. A refrigerant collector according to claim 13, characterized in that the filter / dryer unit (10) occupy the outlet window (19, 20, 21, 22, 23) almost the entire outer periphery of the filter / dryer unit (10).

15. Refrigerant collector according to claim 13, characterized in that the outlet windows (19, 20, 21, 22, 23) of the filter / dryer unit (10) are provided with a filter (30).

16. Refrigerant collector according to claim 1, characterized in that the filter (30) of the filter / dryer unit (10) is gebil det through a fine mesh stainless steel mesh.

17. Refrigerant collector according to claim 1, characterized in that the filter / dryer unit (10) has a plastic housing (11).

18. Refrigerant collector according to claim 17, characterized in that the filter / dryer unit (10) has a bottom which is latched to the rest of the housing (11).

19. Refrigerant collector according to claim 1, characterized in that the filter / dryer unit (10) is arranged approximately halfway up the interior (9) or above.

20. A refrigerant collector according to claim 2, characterized in that the suction opening (37) on the bottom (5) facing the underside of the pipe bend (35) is arranged.