PROPORTIONAL VALVE, AIR-CONDITIONER COMPRESSOR ARRANGEMENT, AND OPERATING METHOD

Abstract

An electromagnetically actuatable proportional valve (1), in particular differential pressure valve for use in CO.sub.2 air conditioning compressor arrangements, comprising an electromagnetic actuator (3) for adjusting a valve body (2) relative to a valve seat (5), wherein the valve seat (5) is assigned a first pressure connection (7), via which a fluid can flow bypassing the valve body (2) to a second pressure connection (9), wherein the valve body (2) delimits a diffuser chamber (30) which with the valve body (2) lying against the valve seat (5) is connected in a fluid-conducting manner with the first pressure connection (7) via a fluid connection (22) delimited by the valve body (2).

Claims

1. An electromagnetically actuatable proportional valve (1), in particular differential pressure valve for use in CO.sub.2 air conditioning compressor arrangements, comprising an electromagnetic actuator (3) for adjusting a valve body (2) relative to a valve seat (5), wherein the valve seat (5) is assigned a first pressure connection (7), via which a fluid can flow bypassing the valve body (2) to a second pressure connection (9), wherein the valve body (2) delimits a diffuser chamber (30) which with the valve body (2) lying against the valve seat (5) is connected in a fluid-conducting manner with the first pressure connection (7) via a fluid connection (22) delimited by the valve body (2).

2. The proportional valve according to claim 1, wherein the valve body (2) in a section delimiting the diffuser chamber (30) comprises a conical lateral surface (27).

3. The proportional valve according to claim 2, wherein the valve body (2) is assigned an internal cone surface (28) which in sections encloses the valve body (2) radially on the outside, which delimits the diffuser chamber (30) and wherein a cone angle of the conical lateral surface (27) is smaller, than the cone angle of the internal cone surface (28).

4. The proportional valve according to claim 3, wherein the internal cone surface (28) is formed on an orifice component (21) forming the valve seat (5).

5. The proportional valve according to claim 1, wherein the diffuser chamber (30), with the valve body (2) lying against the valve seat (5), opens with an opening angle from a value range between 10° and 35°, over a length between 0.5 mm and 10 mm.

6. The proportional valve according to claim 1, wherein the fluid connection (22) comprises a shaped recess (25) or a flat in/on the valve body (2) and/or a component forming the valve seat (5).

7. The proportional valve according to claim 1, wherein for forming the fluid connection (22), a distance elevation (29) is provided.

8. The proportional valve according to claim 1, wherein a chamber (14) receiving an armature (15) of the electromagnetic actuator (3) and/or a force transmission plunger for adjusting the valve body (2) is connected in a fluid-conducting manner with a third pressure connection (10).

9. The proportional valve according to claim 1, wherein the valve body (2) is adjustable onto the valve seat (5), by energising a coil arrangement (4) of the electromagnetic actuator (3).

10. An air conditioner compressor arrangement, in particular in a motor vehicle, with a proportional valve (1) designed as differential pressure valve according to claim 1 and an air conditioning compressor, wherein on the first pressure connection (7) a delivery pressure of the air conditioning compressor and on the second pressure connection (9) a crankshaft pressure (P.sub.C) can be applied and/or is applied.

11. The air conditioning compressor arrangement according to claim 10, wherein on a third pressure connection (10) of the proportional valve (1) which is connected with a chamber (14) receiving an armature (15) of the electromagnetic actuator (3) and/or a force transmission plunger for adjusting the valve body (2) in a fluid-conducting manner, a suction pressure (P.sub.S) of the air conditioning compressor can be applied and/or is applied.

12. A method for operating an electromagnetically actuated proportional valve (1) according to claim 1, wherein the diffuser chamber (30) with the valve body (2) lying against the valve seat (5) is supplied with fluid from the first pressure connection (7), which furthermore flows to the second pressure connection (9) and by flowing through the diffuser chamber (30) the fluid pressure force acting from the first fluid connection onto the valve body (2) is reduced.

13. The proportional valve according to claim 1, wherein the valve body (2), is formed as a valve plunger.

14. The proportional valve according to claim 3, wherein the cone angle of the conical lateral surface (27) is smaller by an angle from an angular range between 0.1° and 30°.

15. The proportional valve according to claim 5, wherein the opening angle is between 15° and 25° and the length is between 1 mm and 4 mm.

16. The proportional valve according to claim 6, wherein the shaped recess is produced through material forming, or wherein the flat is produced by removing material, and/or wherein the component forming the valve seat (5) is an orifice component (21).

17. The proportional valve according to claim 7, wherein the distance elevation protrudes over a lateral surface of the valve body (2).

18. The proportional valve according to claim 8, wherein the third pressure connection (10) is a suction pressure connection.

19. The proportional valve according to claim 9, wherein the valve body (2) is adjustable onto the valve seat (5) against a resetting force produced by a resetting spring.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Further advantages, features and details of the invention are obtained from the following description of preferred exemplary embodiments and by way of the drawings.

[0024] These show in:

[0025] FIG. 1: a longitudinal sectional view of a preferred embodiment of an electromagnetically actuated proportional valve designed according to the concept of the invention,

[0026] FIGS. 2a to 2d: different views of a component delimiting a diffuser chamber of the proportional valve, here of an orifice component,

[0027] FIGS. 3a to 3d: different views of a possible design of a plunger-shaped valve body,

[0028] FIGS. 4a to 4d: different representations of an alternative embodiment of a valve body with groove-like shaped recesses for delimiting the fluid connection,

[0029] FIGS. 5a to 5d: four different views of a further alternative embodiment of a valve body with lateral flats in a cone section for delimiting the fluid connection, and

[0030] FIGS. 6a to 6d: different views of an arrangement of valve body and a further component, here exemplarily of an orifice component for delimiting a diffuser chamber and a fluid connection.

DETAILED DESCRIPTION

[0031] In the figures, same elements and elements with the same function are marked with the same reference characters.

[0032] In FIG. 1, an electromagnetically actuated (actuatable) proportional valve 1 is shown in a longitudinal section for use in CO.sub.2 air conditioner compressor arrangements.

[0033] This comprises a valve body 2 designed as a valve plunger, which is axially adjustable onto the valve seat 5 by energising an electromagnetic actuator 3, more precisely an electric coil arrangement 4 of the actuator 3 axially relative to a valve seat 5, here against the spring force of a resetting spring 6 supporting itself on the valve body 2.

[0034] The valve seat 5 is assigned to a first pressure connection 7. The first pressure connection 7 is a high pressure connection, on which a high pressure P.sub.D, here a compressor delivery pressure is present. Fluid, here a CO.sub.2 oil mixture, can flow, with the valve body 2 lifted off the valve seat 5, i.e. adjusted upwards in the drawing plane (and as will still be explained later on also with the valve body 2 lying against the valve seat 5), bypassing the valve seat 5 and the valve body 2, to a valve body chamber 8 (dispensing chamber) receiving the resetting spring 6 and the valve body 2 and from the same to a second pressure connection 9, at which during the operation a crankshaft pressure P.sub.C is present.

[0035] The proportional valve 1 comprises a further, namely a third pressure connection 10, in which during the operation a suction pressure of the compressor is present. The pressure connections 7, 9, 10 are sealed via axially offset seals 11, 12, 13, here designed as O-ring seals, fluid-tight against one another.

[0036] The third pressure connection 10 opens into a chamber 14, in which pressure-balanced an armature 15, that is axially adjustable by energising the coil arrangement 4, is received in an axially pressure-balanced manner.

[0037] In the armature 15, a first plunger 16 is received for transmitting an adjusting force to a preferably diameter-reduced second plunger 17, which in turn axially supports itself on the valve body 2.

[0038] The object of the shown proportional valve in its function as differential pressure regulating valve is to adjust a certain pressure differential, proportionally to the current applied to the electric coil arrangement, between the first and the third pressure connection 7, 10, i.e. a pressure differential between P.sub.D and P.sub.S. However, the proportional valve is flowed through from the first to the second pressure connection 7, 9 while the third pressure connection 10 does not lie in the valve or fluid flow, but is utilised as pressure return for the pressure suction pressure P.sub.S.

[0039] Depending on the stroke of the valve body 2 (regulating pin) relative to the valve seat 5, the pressure drop from P.sub.D to P.sub.C and following this also the system pressure differential in an air conditioning compressor arrangement which is not otherwise shown further, be varied from P.sub.D to P.sub.S.

[0040] When the coil arrangement 4 is energised, this results in a magnetic force which moves an armature assembly, here concretely the armature 15 together with the plungers 16, 17 and the valve body 2 in the direction of the valve seat 5, wherein the armature 15 is adjusted in the direction of a core bottom 18. The movement of the valve body 2 and thus the entire armature movement takes place against the resetting force of the resetting spring 6, as a result of which the valve body 2 moves against the spring force of the resetting spring 6 onto its valve seat 5. Here, the armature 15, as already mentioned, lies in the chamber 14, which is at suction pressure P.sub.S, in a pressure-balanced manner. The second plunger 17 separates the valve body chamber 8, being at crankshaft pressure P.sub.C, from the chamber 14 being subject to suction pressure P.sub.S. Since the crankshaft pressure P.sub.C during the operation is always greater than the suction pressure P.sub.S, the electromagnetic actuator 3, when adjusting the valve body 2 in the direction of its valve seat 5 also has to overcome the pressure force which acts on the plunger through the pressure differential between P.sub.C and P.sub.S. When the suction pressure P.sub.S changes, this of necessity also has repercussions on the pressure differential between P.sub.C and P.sub.S, which acts on the second plunger 17. Thus, when the suction pressure P.sub.S changes, this has repercussions also on the counterforce, as a result of which returning the suction pressure P.sub.S into the regulation is ensured. In addition to the aforementioned counterforce, the magnet also has to work against the resetting force (spring force) of the resetting spring 6 and also those fluid forces which act on the valve body 2. This is primarily a pressure force resulting from the high pressure (delivery pressure) P.sub.D that is present at the first pressure connection 7, to which the valve body 2 is exposed.

[0041] For minimising the influence of the pressure P.sub.D that is present on the first pressure connection 7 on the adjusting movement or the necessary magnetic force it is provided here that the valve seat 5 is assigned a diffuser chamber 30, which is delimited by a cone section 19 of the valve body. This diffuser chamber 30, which, located opposite the valve body 2, is delimited by an internal cone 20 of an orifice component 21 comprising an internal cone surface 28, is connected, with the valve body 2 lying against the valve seat 5, to the first pressure connection 7 in a fluid-conducting manner via a direct fluid connection 22, which is delimited by the valve body 2 and in the present exemplary embodiment additionally by the orifice component 21. The orifice component 21 can be fixed for example by pressing (or other fastening means) into a body 23, into which on the one hand the valve body chamber 8 and also the three pressure connections 7, 9, 10 are introduced. On this body 23, the electromagnetic actuator 3 with its magnetic flux-conducting housing 24 is also fixed. With fluid flowing through the diffuser chamber 3 from the first pressure connection 7 to the second pressure connection 9, a low-pressure region is created because of the diffuser effect in the region of the cone section 19 of the valve body 2, which reduces the pressure forces on the valve body 2 caused by the high pressure (delivery pressure) P.sub.D in the direction of the actuator 3 away from the valve seat 5 to a negligible value. By realising the aforementioned fluid connection 22 delimited by the valve body 2 and the fluid flow resulting from this even in the quasi-closed state of the proportional valve, this diffuser effect is maintained even with the valve body 2 lying against the valve seat 5.

[0042] In FIGS. 2a to 2d a possible embodiment of an orifice component 21 is shown. Visible is an internal cone 20 with an internal cone surface 28 delimiting the diffuser chamber 30. The internal cone 20 encloses in sections the valve body 2 or the latter axially plunges into the internal cone 20 in order to strike against or lie against the valve seat 5 provided in an axial end region of the internal cone 20.

[0043] Exemplarily visible here are two shaped recesses located opposite one another and extending along the longitudinal extent of the diffuser chamber 30 as a component part of the fluid connection 22, which located opposite is delimited by the valve body 2 (not shown here) and takes care that the diffuser chamber 30 is permanently connected with the first pressure connection 7 (see FIG. 1) and thus with the high pressure P.sub.D in a fluid conducting manner in particular even with the valve body 2 lying against the valve seat 5.

[0044] As is evident from the sectional view A-A according to FIG. 2b, the internal cone 20 opens into a cylindrical duct 26, which forms the fluid-conducting connection between the fluid connections 22 and the first pressure connection 7.

[0045] In FIGS. 6a to 6d, the described orifice component 21 combined with a valve body 2 designed as valve plunger is shown in detail by way of FIGS. 2a to 2d.

[0046] From the detail enlargement X according to FIG. 6d it is evident that a cone angle, more precisely an internal cone angle α1 of the internal cone surface 28, which delimits the diffuser chamber 30, is slightly larger than a cone angle α2 of a conical lateral surface 27 formed on the cone section 19 (see FIG. 1), which together with the internal cone surface 28 delimits the diffuser chamber 30.

[0047] In FIG. 6b, the fluid connections 22 are noticeable, via which the diffuser chamber 30 is permanently supplied with fluid from the first pressure connection 7, i.e. even with the valve body 2 lying against the valve seat 5.

[0048] By way of FIGS. 3a to 3d an alternative possibility for forming the fluid connection 22 between the diffuser chamber 30 and the first pressure connection is evident. It is noticeable that on the valve body 2, here in the region of the cone section 19 in this case exemplarily elongated spacing elevations 29 which are arranged evenly distributed over the circumference are provided, with which the valve body 2 can support itself in particular on an orifice component 21, in particular within an internal cone 20. The region in circumferential direction between the spacing elevations 29 is thereby slightly spaced from the internal cone 20, so that a permanent fluid connection 22 is ensured.

[0049] A further possibility for realising the fluid connection 22 consists in providing material shaped recesses or milled-out portions, here in the manner of elongated grooves on the valve body 2, in particular in the region of a cone section 19, through which fluid can flow into the diffuser chamber 30 delimited by the valve body even with the valve body 2 lying against the valve seat 5.

[0050] In FIGS. 5a to 5d, a further alternative design of fluid connections 22 is realised in the form or lateral flats on the valve body 2, preferably in a cone section 19.