EP1316765B1 - Accumulator for an air conditioner, particularly for vehicle air conditioners - Google Patents

Description

The invention relates to an accumulator for an air conditioning system, in particular vehicle air conditioning system, according to the preamble of claim 1.

Such an accumulator is known from US 4,627,247. There, refrigerant is passed without the interposition of a pipe in the interior of the housing, wherein a baffle arranged in the upper region of the housing initially deflects the incoming refrigerant down where the liquid portion collects. The gaseous portion flows upwards and enters the first of two tubes, which run parallel to the axis of the housing and form an overall U-shaped flow path. The production of the baffle is associated with high tooling costs.

An accumulator similar to that of the aforementioned type is known from EP 1 132 696 A1. In this, a third tube is integrally integrated in the housing to be arranged in the housing, which leads the coming of the inlet opening refrigerant axially downwards over about one third of the height of the housing and omits at this height in the interior of the housing. This measure is intended to prevent the liquid phase of the refrigerant, without reaching the desiccant disposed in the lower region of the housing, from flowing directly to the upper inlet opening of the first tube and thus, without being sufficiently dried, through the first one and second pipe flows to the outlet port of the housing. Rather, before the flow through the first and second tube, a separation of the liquid and the gaseous phase of the refrigerant take place. A disadvantage of this embodiment is that the production of the insert requires relatively complicated tools and that in addition takes place through the additional pipe further throttling of the refrigerant flow.

From EP 1 035 388 A2 an accumulator similar to that of the aforementioned type is known. Here, the flow path comprises two siphon-like tubes. A guide device provided at the inlet opening ensures a circular flow of the incoming refrigerant and thereby a separation of the liquid from the gaseous component. The production of this accumulator is relatively expensive.

Object of the present invention is to form a rechargeable battery of the type mentioned in such a way that its production is simplified.

This object is achieved by the accumulator specified in claim 1.

According to the invention is therefore on the third pipe section, which is found in the subject of EP 1 132 696 A1 and over which the refrigerant is passed from the inlet opening of the housing into the interior of the housing, simply omitted. This makes the production of the insert considerably cheaper and also reduces the throttling of the refrigerant. In order to prevent the direct "short-circuit" of the refrigerant flow from the inlet opening of the housing to the upper inlet opening of the first tube, integrally molded barriers are provided according to the invention. These can be made very easy to spray because they are not self-contained Need to represent pipe and also have no draft as in the baffle of the aforementioned US 4,627,247.

By these two barrier-forming wings, the upper portion of the interior of the housing is divided into two parts, one of which is adjacent to the inlet opening of the housing and the other of the at least one inlet opening of the first tube. Without complicated shapes, the mentioned unwanted short-circuit flow of the refrigerant is avoided in this way.

It is preferred if the first tube is closed in its upper end by a cover and the at least one inlet opening of the first tube is formed in the cylinder wall of this tube. In the subject matter of the above-mentioned EP 1 132 696 A1, the first pipe is simply open at the top, which makes the inflow of the refrigerant more difficult since it causes a deflection of the refrigerant flow through 180 °.

At the upper region of the insert, below the at least one inlet opening on the side of the barrier which faces away from the inlet opening of the housing, a radially extending sieve carrier holding a sieve can be provided. The screen, which can be formed very fine mesh, serves to retain particles and any drops of liquid refrigerant on the way to the inlet opening of the first pipe rise up, to atomize and thus promote their evaporation.

Particularly preferred is an embodiment of the invention in which the second tube has a smaller diameter than the first tube and extends within the first tube. This "nesting" of the two tubes into each other is extremely space-saving. The downwardly directed flow path of the refrigerant in this embodiment extends through the gap between the first and the second tube. The refrigerant is in this way with a suitable choice of the diameter on its descending flow path, a larger flow area than on its rising flow path available. This is desirable for reasons of low flow resistance. It should be noted that the flow cross-section in the region of the deflection of the flow at the connected lower ends of the two tubes should be reduced, since here often sucked in a small, communicating with the lower portion of the housing passage opening a mixture of refrigerant and oil and entrained shall be. In the reboiling section of the flow path of the refrigerant, the flow velocity should at least be so high that the entrained oil droplets do not separate again. With the described "nesting" of the first and second tube, the flow cross sections in the descending and ascending slices of the flow path of the refrigerant can be easily adjusted without problems.

It is favorable in terms of production, if - in the described nesting of the first and the second tube - the second tube extends eccentrically within the first tube, such that it along a vertical Line has a common wall area with the first pipe. The flow area on the descending portion of the flow path of the refrigerant is sickle-shaped in this embodiment.

The lower ends of the first tube and the second tube may be connected to each other via a cup-shaped deflection cap which has a passage opening leading to the interior of the housing, wherein the inner surface of the deflection cap in the vicinity of the passage opening has a profiling, which leads to a local increase in the flow velocity leads. With this configuration, in the transition area between the first and the second tube in the vicinity of the through opening communicating with the lower housing area, a narrowing of the flow cross section of the refrigerant can be achieved, which enhances the suction effect at the passage opening.

Figur 1

einen vertikalen Schnitt durch einen Akkumulator gemäß der Linie I-I von Figur 5;

Figur 2

einen Schnitt durch einen in dem Akkumulator von Figur 1 enthaltenen Einsatz in der selben Schnittebene wie Figur 1;

Figur 3

einen Schnitt durch den Einsatz der Figur 2, jedoch gemäß Linie III-III von Figur 5;

Figur 4

eine perspektivische Ansicht des Einsatzes der Figuren 2 und 3;

Figur 5

eine Draufsicht auf den Einsatz der Figuren 2 bis 4;

Figur 6

einen horizontalen Schnitt durch den Einsatz der Figuren 2 bis 5 gemäß der Linie VI-VI von Figur 2.

An embodiment of the invention will be explained in more detail with reference to the drawing; show it

FIG. 1

a vertical section through an accumulator according to the line II of Figure 5;

FIG. 2

a section through an insert contained in the accumulator of Figure 1 in the same sectional plane as Figure 1;

FIG. 3

a section through the use of Figure 2, but according to line III-III of Figure 5;

FIG. 4

a perspective view of the insert of Figures 2 and 3;

FIG. 5

a plan view of the use of Figures 2 to 4;

FIG. 6

a horizontal section through the use of Figures 2 to 5 according to the line VI-VI of Figure 2.

The accumulator shown in Figure 1, which is generally designated by the reference numeral 1, comprises a cylindrical in cross-section, one-piece and downwardly open housing 2. In the upper part 2a of the housing 2, parallel to each other, an inlet bore 3, which extends downwards funnel-shaped, and an outlet hole 4 is provided. In the housing 2, an insert is inserted from below, which is generally designated by the reference numeral 5 and described in more detail below with reference to Figures 2 to 6. After assembly of the insert 5, the housing 2 is sealed by a bottom 40, which is welded, for example. Between the bottom 40 and the insert 5, a spring 41 is clamped. This compensates for component tolerances and prevents rattling.

The insert 5 is composed of a head part 5a, a middle part 5b, a receiving part 5c for a desiccant, a cup-shaped, upwardly opening deflection cap 5d and a lower part 5e, which are detachably connected to one another by snap connections. The separation between the individual parts 5a, 5b, 5c, 5d and 5e is done exclusively according to manufacturing aspects; it basically has no influence on the function of the insert 5.

The upper head part 5a comprises two nested tubes 6, 7, which are not coaxial with each other run. Rather, the tube 7, which has the smaller diameter, at a location on the pipe 6 of larger diameter; in fact, the walls of the two tubes 6, 7 fuse together at this point. A one-piece cover 8 of the head part 5 closes the outer tube 6; the inner tube 7 pierces the lid 8 upwards and projects with an insertion region 7a.

As can be seen in particular from FIGS. 3 and 4, two arcuate vanes 9, 10 are formed on the outer tube 6, the radially outer end faces 11, 12 of which rest against the inner circumferential surface of the housing 2 in the assembled state.

The outer tube 6 of the head part 5a expands in its lower region to a connecting skirt 13, in which from below the middle part 5b described below is inserted and locked there. On the connecting skirt 13, a radially extending filter holder 14 is integrally formed, which extends from the underside of a wing 9 to the underside of the other wing 10. The cylindrical end face 15 of the portafilter 14 is in the assembled state on the inner circumferential surface of the housing 2. The portafilter 14 holds a screen 16, which covers the area between the two wings 9, 10, the connecting skirt 13 and the cylindrical end face 15 of the portafilter 14.

As can be seen in particular from FIG. 4, the outer tube 6 has two inlet openings 17, 18 in its lateral surface on the side of the two wings 9, 10 facing the viewer in FIG Pipe 6 lying, crescent-shaped space lead.

The middle part 5b of the insert 5 which is inserted with its upper region into the connecting skirt 13 of the head part 5a also has an outer tube 19 of larger diameter and an inner tube 20 of smaller diameter whose geometrical arrangement is that of the two tubes 6, 7 in the head part 5a corresponds and which of these tubes 6, 7 continue downward. The length of the middle part 5b can be chosen differently for different lengths of housing.

The lower end of the central part 5b is inserted into an upwardly extending connecting skirt 21 of the receiving part 5c and latched there. Also, the receiving part 5c includes the already known arrangement of an outer tube 22 of larger diameter and an inner tube 23 of smaller diameter, which continue the tubes 19, 20 of the central part 5b and the tubes 6, 7 of the head part 5a down.

On the outer circumferential surface of the outer tube 22 is integrally formed a radially outwardly extending flange 24 which includes a plurality of openings 25. The circular in plan view, the flange 24 has a diameter corresponding to the inner diameter of the housing 2. From the outer edge of the flange 24 extends, in turn integrally formed, a cylindrical wall 26 down.

On the lower end of the outer tube 22 of the receiving part 5 c, the deflection cap 5 d is snapped with a connecting skirt 27. The deflection cap 5 d connects, similar to the arc of a siphon, the flow space between the outer tube 22 and the inner tube 23 of the receiving part 5 c with the interior of the inner tube 23rd

Through the lowest point of the deflection cap 5d, a through hole 28 is passed, which opens into the inner surface of the deflection cap 5d in the region of a small elevation. Adjacent to this through hole 28 are on the inner surface of the Umlenkkappe 5 d two upstanding ribs 29, 30 (see in particular Figure 6) formed, on the side of the bore 28, which lie between the tubes 22 and 23 of the receiving part 5 c Flow chamber points.

In the cylinder wall 26 of the receiving part 5c is finally from below a radially extending flange 31 of the lower part 5e of the insert 5 is inserted and locked there. The radially extending flange 31 of the lower part 5 e contains through holes 23 similar to the radially extending flange 24 of the receiving part 5 c.

The radially extending flanges 24 and 31, the cylinder wall 26 and the outer tube 22 of the receiving part 5c limit in this way an annular receiving space 33, in which a bed of desiccant can be introduced.

Of the flange 31 of the lower part 5e extend two corresponding to the shape of the deflection cap 5d in the radius stepped annular wall portions 34 down, which are integrally closed at the bottom by a bottom 35. In the lowermost annular wall portion 34 a plurality of window-like openings 36 are introduced, so that the space lying within the wall portions 34 can communicate with the outside space. In the window-like openings 36 are not shown sieves, which prevent particles through the through hole 28 of the deflection cap 5 d are washed and enter the subsequent refrigerant circuit or even clog the through hole 28.

The entire insert 5 described above is, as already indicated, inserted into the housing 2 of the accumulator 1 shown in FIG. 1 from below. The insertion region 7a of the head part 5a of the insert 5 is thereby inserted into the outlet opening 4 of the upper housing part 2a. The end faces 11, 12 of the wings 9, 10 on the head part 5a of the insert 5 and the end face 15 of the screen support 14 of the head part 5a and the outer surface of the cylindrical wall 26 of the receiving part 5c lie against the inner surface of the cylinder wall 2b of the housing 2 , Now, the housing 2 can be closed by the bottom 40 after insertion of the spring 41, which is either screwed into the cylindrical housing wall 2b or welded thereto.

The function of the described accumulator 1 is as follows:

Coming from the evaporator refrigerant, which is primarily in the gas phase, but also carries liquid refrigerant and oil with it, passes through the inlet bore 3 of the housing 2 in the interior of the housing 2, but by the wings 9, 10 at the top 5a of the insert 5 is prevented from flowing "in short" directly to the inlet openings 17, 18 in the head part 5a of the insert 5. Instead, the refrigerant is "forced" downwards and thus arrives in the region of the openings 25 in the receiving part 5c and from there into the inner space 33 of the receiving part 5c and is largely freed of water from the desiccant located there. Part of it seeps through the bottom Openings 32 of the receiving space 33 again.

The gaseous refrigerant passes on the way to the inlet openings 17, 18 of the head part 5 a of the insert 5, the sieve 16, possibly still entrained residues of liquid particles are very finely atomized, which facilitates their residual evaporation.

The now almost exclusively consisting of a gas phase refrigerant is introduced via the inlet openings 17, 18 in the space between the outer tube 6 and the inner tube 7 of the head part 5a of the insert 5, then flows through the gap between the outer tube 19 and the inner tube 20 of the central part 5b and the gap between the outer tube 22 and the inner tube 23 of the receiving part 5c. Then it is deflected by the siphon-like deflection cap 5 d and introduced into the inner tube 23 of the receiving part 5 c, from where it flows upwards the interior of the inner tube 20 of the central part 5 b and the interior of the inner tube 7 of the head part 5 a of the insert 5 and then leaves through the outlet hole 4 of the housing 2 of the accumulator 1.

The refrigerator oil remains liquid and collects in the liquid refrigerant phase in the lower region of the housing 2 and is sucked through the through hole 28 in the deflection cap 5 d. For this purpose, the gaseous refrigerant, which is deflected by the deflecting cap 5d, flows over the through-flow bore 28. The flow velocity is increased in the region of the through-bore 28 by the action of the two ribs 29, 30, which narrow the flow path of the refrigerant. This increases the suction of the flowing refrigerant to the liquid oil / refrigerant mixture, which is below the Umlenkkappe 5d and communicates via the window-like openings 36 with the through hole 28. The mixture is entrained and executed together with the refrigerant from the accumulator 1.

Claims (6)

1. Accumulator for an air conditioning system which works according to the orifice principle, in particular a vehicle air conditioning system, with

   a) a housing which comprises an inlet opening and an outlet opening for coolant;

   b) an insert which can be disposed in the housing and which comprises at least one part in which there are assembled in one piece:

   ba) a first pipe which opens in the upper region via at least one inlet opening to the interior of the housing and runs approxiamately paraxially with the housing;

   bb) a second pipe which runs approximately paraxially with the housing and at its lower end communicates with the lower end of the first pipe and at its upper end with the outlet opening;

   wherein

   c) the inlet opening (3) of the housing (2) leads directly without the interposition of a pipe section into the interior of the housing (2);

   d) a barrier (9, 10) is formed onto the upper region (5a) of the insert (5), which barrier suppresses the direct flow of the coolant between the inlet opening (3) of the housing (2) and the at least one inlet opening (17, 18) of the first pipe (6, 19, 22),
   characterised in that

   e) the barrier (9, 10) is formed by two wings (9, 10) which extend from the upper region (5a) of the insert (5) radially outwards into the vicinity of the wall (2b) or up to the wall (2b) of the housing (2).
2. Accumulator according to Claim 1, characterised in that the first pipe (6, 19, 22) is closed at its upper end by a cover (8), and the at least one inlet opening (17, 18) of the first pipe (6, 19, 22) is formed in the cylindrical wall of this pipe (6, 19, 22).
3. Accumulator according to any one of the preceding Claims, characterised in that a radially extending screen support (14) holding a screen (16) is provided at the upper region (5a) of the insert (5) below the at least one inlet opening (17, 18) on the side of the barrier (9, 10) which is remote from the inlet opening (3) of the housing (2).
4. Accumulator according to any one of the preceding Claims, characterised in that the second pipe (7, 20, 23) has a smaller diameter than the first pipe (6, 19, 22) and runs inside the first pipe (6, 19, 22).
5. Accumulator according to Claim 4, characterised in that the second pipe (7, 20, 23) runs eccentrically inside the first pipe (6, 19, 22) such that it has a common wall region with the first pipe (6, 19, 22) along a vertical line.
6. Accumulator according to any one of Claims 1 to 5, characterised in that the lower end of the first pipe (6, 19, 22) and of the second pipe (7, 20, 23) are connected together via a shell-shaped deflection cap (5d) which comprises a through-opening (28) leading to the interior of the housing (2), wherein the inner face of the deflection cap (5d) has profiling (29, 30) in the vicinity of the through-opening (28) which results in a local increase in the flow speed.

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