VALVE DEVICE

Abstract

A valve device for a cooling water system of a motor vehicle, with a housing including a first connection and a second connection for a first liquid circuit, and a third connection and a fourth connection for a second liquid circuit, wherein the first connection is permanently fluidically connected to the second connection, and with a valve unit including a movably mounted valve element with which a thermally activatable spring element is associated, and which opens a connection between the third connection and the fourth connection in a first end position and cuts off the connection in a second end position. The thermally activatable spring element is arranged in a chamber located between the first connection and the second connection, which is permanently cut off from the third and the fourth connection and which preloads the valve element in the direction of the second end position.

Claims

1. A valve device, in particular for a cooling water system of a motor vehicle, with a housing comprising a first connection and a second connection for a first liquid circuit, and a third connection and a fourth connection for a second liquid circuit, wherein the first connection is permanently fluidically connected to the second connection, and with a valve unit comprising a movably mounted valve element with which a thermally activatable spring element is associated, and which opens a connection between the third connection and the fourth connection in a first end position and cuts off the connection in a second end position, wherein the thermally activatable spring element is arranged in a chamber located between the first connection and the second connection, which is permanently cut off from the third and the fourth connection and which preloads the valve element in the direction of the second end position, and in that the valve unit is designed as a plug-in module which can be plugged into the housing and comprises a cylindrical module housing comprising at one end a bottom with an opening, which delimits the chamber, wherein the valve element is slidably mounted in the module housing and led radially by means of a free end in a sealing/tight manner through the opening.

2. The valve device according to claim 1, wherein the return spring on the valve element opposes the thermally activatable spring element.

3. The valve device according to claim 1, wherein the free end of the valve element supports a sealing body, which is designed to cooperate in the second end position with a valve seat of the housing, so that the connection is cut off.

4. The valve device according to claim 1, wherein the valve element comprises at least one radial projection in the area of the chamber, and that the spring elements are axially supported on the radial projection.

5. The valve device according to claim 1, wherein at least two openings formed in a shell wall of the module housing are associated with the chamber, wherein one of the openings is/can be associated with the first connection and the other of the openings is/can be associated with the second connection.

6. The valve device according to claim 1, wherein the module housing and the housing comprise at least one positive locking anti-rotation means.

7. The valve device according to claim 1, wherein the radial projection is formed by a support sleeve which is pushed onto the valve element and which is held axially by positive and/or frictional locking on the valve element.

8. The valve device according to claim 1, wherein the support sleeve (36) comprises at least one radially inward protruding support projection which engages in a radial recess of the valve element.

9. The valve device according to claim 1, wherein the shell wall of the module housing comprises at least one slit-shaped recess, and that a holding element having an opening is plugged laterally through the slit-shaped recess into the module housing.

10. The valve device according to claim 1, wherein the return spring is axially supported on the holding element.

11. The valve device according to claim 1, wherein between the holding element and the bottom, a resiliently deformable sealing element, in particular a sealing ring, is arranged, which is in contact radially with the valve element in a sealing/tight manner and in particular is held preloaded.

12. The valve device according to claim 1, wherein the housing, the third connection lies in the movement direction of the valve element and the fourth connection lies perpendicularly thereto.

13. A cooling water system for a motor vehicle, with a first liquid circuit and a second liquid circuit, and with a valve device which is associated both with the first liquid circuit and also with the second liquid circuit, wherein the design of the valve device is according to claim 1.

Description

[0020] Below, the invention will be explained in further detail in reference to an embodiment example.

[0021] FIG. 1 shows an advantageous valve device in a cross-sectional representation,

[0022] FIG. 2 shows a detail view of the valve device in a cross-sectional representation,

[0023] FIGS. 3A and 3B show a detail of the valve device in different views,

[0024] FIGS. 4A to 4C show an additional detail of the valve device in different views, and

[0025] FIG. 5 shows an additional detail view of the valve device.

[0026] FIG. 1 shows, in a longitudinal cross-sectional representation, a valve device 1 for a cooling water system of a motor vehicle which is not represented in further detail. The valve device 1 comprises a housing 2 which is designed so that it conveys liquid and which, for that purpose, comprises a first connection 3, a second connection 4, a third connection 5, and a fourth connection 6. The connections 3, 4, 5, 6 can each be connected to a liquid line of the cooling water system. Here, the cooling water system or the valve device is preferably designed in such a manner that the connections 3 and 4 are part of a first cooling water circuit, in particular a high-temperature circuit, of the cooling water system, and the connections 5 and 6 are part of a second cooling water circuit, in particular a low-temperature circuit, of the cooling water system.

[0027] The connections 3, 4 lie in the present case on the housing 2 on opposite sides in alignment with one another, and the connections 5 and 6 are arranged at right angles to one another in such a way that the connection 6 extends parallel to and spaced apart from the connections 3, 4, while the connection 5 is oriented perpendicularly thereto.

[0028] The housing 2 comprises a recess 7 which is of cylindrical design, wherein each of the connections 3, 4, 5, 6 leads into the recess 7, so that, by means of the recess 7, all the connections 3 to 6 are fluidically connected to one another. The recess 7 is designed here to be axially marginally open between the connections 3 and 4 in the housing 2.

[0029] In the recess 7, a valve unit 8 is inserted, which is designed as plug-in module and can accordingly be plugged axially into the recess 7. The valve unit 8 comprises a beaker-shaped module housing 9 which comprises a bottom 10 as well as a shell wall 11 starting from the bottom 10. The bottom 10 and the shell wall 11 here have an outer contour which corresponds at least substantially to the inner contour of the recess 7, so that the valve unit 8 is held at least substantially by positive locking in the recess 7 or in the housing 2. In the bottom 10, an opening 12 is formed in the center, and, in the shell wall 11, two mutually opposite openings 13 and 14 are formed. The openings 13, 14 are here each associated with one of the connections 3 and 4, in order to fluidically connect the chamber 15 located in the module housing 9 to the first hydraulic circuit or to the connections 3 and 4. For example, liquid flowing from the connection 3 to the connection 4 thus also flows through the chamber 15 or the inner space of the module housing 9.

[0030] In the module housing 9, a valve element 16 which is of rod-shaped design is mounted axially shiftably. Here, the valve element 16 is passed by means of a free end 17 through the opening 12 of the bottom 10, so that it protrudes on the side of the bottom 10 which is opposite the chamber 15. On the other end thereof, the valve element 16 is held axially in a guide recess 18 of a cover 19, which closes the module housing 9 on the side facing away from the bottom 10, and which moreover fastens the valve unit 8 to the housing 2. For this purpose, the cover 19 in the present case is welded at an outer margin thereof to the housing 2 with which it is in contact axially.

[0031] FIG. 5 shows, in a simplified perspective representation, a detail view of the guide recess 18. Said guide recess is designed as guide sleeve 20 which is designed as slit in longitudinal direction, or interrupted when viewed in the circumferential direction. The valve element 16 is held axially shiftably in the recess 18.

[0032] FIG. 2 shows an enlarged partial view of the valve device 1 in the area of the bottom 10. In the area of the bottom 10, the module housing 9 has a diameter narrowing in the form of a step 21. On this step 21, a sealing ring 22 is held in a radial recess 23 of the module housing 9, so that it is preloaded radially between the module housing 9 and the inner side of the housing 2 of the recess 7.

[0033] On the side of the bottom 10 facing the chamber 15, the bottom 10 moreover has an axial recess 24 which is formed coaxially relative to the opening 12. In this axial recess 24 lies a sealing element 25 in the form of a sealing ring having an X-shaped cross section. The sealing ring lies radially preloaded between one of the sides of the shell wall of the recess 24 and the outer shell wall of the valve element 16, so that the liquid of the first liquid circuit cannot flow past the module housing 9 or through the opening 12 to reach the second liquid circuit.

[0034] As can be seen in FIG. 2, on its free end 17, the valve element 16 supports, in addition, a sealing body 26 which is designed to be resiliently deformable. Since the sealing body 26 is arranged on the free end 17, it is located outside of the module housing 9 in the recess 7, namely in the present case in the area in which the connections 5 and 6 meet one another. Here, the sealing seat 27 is associated with the connection 5. The sealing element 26 and the sealing seat 27 are designed in such a manner that, when the valve element 16 has been moved or shifted in the direction of the connection 5, the sealing element 26 is pressed tightly on the sealing seat 27, in order to cut off the fluidic connection between the connection 5 and the connection 6. In order to hold the sealing element 26 axially on the valve element 16, it lies between two retaining rings or lock rings 28 which are held axially by positive locking on the valve element 16, in that they engage in annular grooves 29 provided there.

[0035] In order to prevent loosening of the seal between the valve element 16 and the module housing 9, which is formed by the sealing element 25, a holding element 30 is present, which will be explained in further detail in reference to FIGS. 3A and 3B.

[0036] FIGS. 3A and 3B show a perspective top view onto the module housing (FIG. 3A) and a perspective cross-sectional representation of same (FIG. 3B). The holding element 30 is designed as a holding plate which has an outer contour on two opposite ends, which matches the outer contour of the module housing 9, so that the holding element 30 ends radially flush with the module housing 9. The module housing 9 comprises two mutually aligned slit-shaped recesses 31 for receiving the holding element, into which recesses the holding element 30 can be inserted, as shown in FIG. 3B. In the center, the holding element 30 has an opening 32, which has an inner diameter which is greater than the outer diameter of the valve element 16, so that said valve element can be led through the opening 32 by means of the free end 17, as shown in FIG. 2. The slit-shaped recesses 31 are here arranged in the vicinity of the bottom 10 in such a manner that the sealing element 25 is held axially between the bottom 10, on the one hand, and the holding element 30, on the other hand. Thereby, the loosening of seal between the valve element 16 and the module housing 9 can thus be prevented reliably.

[0037] FIGS. 4A to 4C show an additional detail of the advantageous valve device 1, in several representations. FIG. 4A here shows a perspective top view onto the recess 7, FIG. 4B shows a perspective top view onto the module housing 9, and FIG. 4C shows a perspective top view onto the module housing 9 inserted in the recess 7.

[0038] According to FIG. 4A, the recess 7 comprises at least one inward pointing radial projection 33 which is designed to be complementary to a radial recess 34 of the module housing 9, as shown in FIG. 4B. In the present case, the radial recess 34 is formed by a flattening of the outer shell wall of the module housing 9. The recess 7 of the housing 2 has a projection 33 corresponding thereto. In the present case, in particular, two of the recesses 34 and projections 33 are arranged opposite one another, as can be seen in particular from FIGS. 4B and 4C. As can be seen in particular from FIG. 4C, the effect of the projection 33 and the respective recess 34 is that the module housing 9 comprises the recess 7 with in each case a contour deviating from a circle, which forms an anti-rotation means 35 between module housing 9 and housing 2. Due to this anti-rotation means 35, it is ensured that the openings 13, 14 are always associated in each case with the connections 3, 4, and thus a reliable operation of the valve device 1 or of the cooling water circuit/cooling water system comprising the valve device 1 is always maintained.

[0039] As can be seen moreover from FIG. 1, a valve sleeve 36 is pushed onto the valve element 16. When viewed axially, the valve sleeve 36 has in the center a radial projection 37 which protrudes radially inward, as well as a radial projection 38 which protrudes radially outward. The valve element 16 has an annular groove 39 which forms a radial recess 42, in which the radial projection 37 engages, so that the valve sleeve 36 is held axially by positive locking on the valve element 16.

[0040] The radial projection 38 is used as supporting projection which forms axial support surfaces for two spring elements 40 and 41. The two spring elements 40, 41 are designed as coil springs and are arranged coaxially relative to the valve element 16. The spring element 40 is supported here at one end on the cover 19 and at the other end on the radial projection 37, and the spring element 41 is supported at one end on the holding element 30 and at the other end on the radial projection 37. While the spring element 41 is a simple coil spring, the spring element 40 is designed as a thermally activatable spring element which is manufactured from a shape memory alloy. This results in the operation described below:

[0041] As long as the liquid conveyed by the connections 3 and 4 does not exceed a critical temperature or activation temperature, the spring element 41 pushes the valve element 16 in the direction of the cover 19, so that the sealing element 26 is removed from the valve seat 27 of the connection 5. However, if the temperature rises above the critical limit value, then the thermally activatable spring element 40 is activated, so that the spring force provided by the said spring element exceeds the spring force of the spring element 41. Thereby, the valve element 16 is shifted in the direction of the bottom 10, so that the sealing element 26 is pressed against the valve seat 27 and thereby closes or cuts off the connection between the connection 5 and the connection 6, so that the second liquid circuit is interrupted or stopped. Due to the advantageous seal by the sealing elements 25 and 22, it is ensured here that the liquid flowing between the connections 3 and 4 also moreover is supplied only to the first liquid circuit and does not reach the second liquid circuit. If the temperature of the liquid in the first liquid circuit drops below the or an additional limit value, then the shape memory alloy is deactivated again, so that the spring element 40 can be compressed by the spring force of the spring element 41, whereby the compressing of the valve element 16 is shifted in the direction of the cover 19 and thereby the sealing element 26 is removed from the seal seat 27, so that the second cooling circuit is opened again.