Check valve and use thereof in a fluid system

Description

[0001] The present invention relates to a check valve intended for use in a fluid system, and to a use of the check valve in the fluid system, in particular in a fluid system of a motor vehicle. Check valves known from the prior art generally have a biasing element, for example in the form of a return spring, which is designed to press a valve member with a sealing element towards a sealing seat of a valve element with such a force when the inlet pressure applied to an inlet opening of the check valve falls below a predetermined value that is such that the sealing element rests against the sealing seat in a closed position of the check valve and closes a through-opening of the valve element.When the predetermined inlet pressure, which is generated, for example, by means of a pump, is exceeded, the check element is brought into an open position by the force of the inlet pressure moving the valve member in the direction away from the sealing seat against the force generated by the preload element, thereby opening the through opening.

[0002] The document JP S63 225773 A relates to a check valve according to the preamble of claim 1.

[0003] An object of an embodiment of the present invention is to provide an improved check valve.

[0004] This object is achieved by a check valve having the features of claim 1. Claims 11 and 12 protect the use of the check valve.

[0005] According to one embodiment of the present invention, a check valve comprises: a housing with a base body having an inlet opening, a valve body having a passage having an outlet opening, wherein the valve body is arranged at least partially in the base body and is axially displaceable relative to the base body, a valve element having a through-opening arranged at least partially in the valve body and axially displaceable relative to the valve body, a valve member arranged in the valve body between the outlet opening and the valve element having a sealing element and a valve stem which is axially displaceable relative to the valve body, a prestressing element which is configured to prestress the valve member with a prestressing force in the direction of the valve element, wherein the check valve further comprises: a further prestressing element which is configured toto prestress the valve element with a prestressing force of the further prestressing element in the direction of the valve member, and / or another prestressing element which is designed to prestress the valve body with a prestressing force of the other prestressing element in the direction of the inlet opening, wherein the valve element has a sealing seat surrounding the through-opening, which sealing seat faces the sealing element, and in a closed position of the check valve, the sealing element rests against the sealing seat and closes the through-opening.

[0006] In this case, the prestressing element and / or the further prestressing element and / or the other prestressing element can be designed, for example, as a respective return spring, in particular a return coil spring. In this case, the prestressing force and the prestressing force of the further prestressing element or the prestressing force and the prestressing force of the other prestressing element or the prestressing force and the prestressing force of the further prestressing element and the prestressing force of the other prestressing element can be coordinated with one another in such a way that, in a stationary closed position of the check valve, at an inlet pressure of a fluid present at the inlet opening that is below a predetermined inlet pressure, which fluid is supplied, for example, from a fluid reservoir to the inlet opening via a supply line to the inlet opening by means of a pump, of a fluid system in which the check valve is used, the sealing element rests against the sealing seat and closes the through-opening.In this case, the pre-tensioning force of the further pre-tensioning element and / or the pre-tensioning force of the other pre-tensioning element are selected in particular such that they are greater, in particular significantly greater, than the pre-tensioning force.

[0007] In a design in which the check valve includes the additional preload element, in the event of a fluid contained in an outlet line connected to the outlet opening freezing, the expansion of the fluid caused by the freezing can be compensated for by the additional preload element being compressed toward the inlet opening by contact with the valve element, which has been displaced toward the inlet opening due to the freezing, counter to the preload force of the additional preload element. This can prevent damage to the check valve in the event of freezing.

[0008] Furthermore, in an embodiment in which the check valve contains the other prestressing element, in the event of freezing and corresponding expansion of a fluid contained in the fluid reservoir and / or a corresponding supply line to the inlet opening of the check valve, the expanding frozen / freezing fluid can press the valve element and the valve member together with the valve body, for example in the event that the axial displacement of the valve stem relative to the valve body in the direction of the outlet opening is limited by a corresponding holding device, in the direction of the outlet opening against the prestressing force of the other prestressing element applied by the other prestressing element, wherein the contact of the sealing seat with the sealing element can cause the latter, together with the valve disk and the valve stem, to also be displaced in the direction of the outlet opening.This can also prevent damage to the check valve in the event of freezing.

[0009] After the fluid has thawed again, the check valve can return to its original position.

[0010] According to one embodiment, the valve body is radially sealed with respect to the base body and / or the valve element is radially sealed with respect to the valve body.

[0011] In one embodiment, this can prevent the fluid from flowing towards the outlet opening if the inlet pressure is lower than the specified inlet pressure.

[0012] According to one embodiment, the housing has a, in particular pot-like, retaining cap with a base having an opening.

[0013] According to one embodiment, the other prestressing element has a first end which is supported on a region of the base of the retaining cap surrounding the opening, and a second end which is supported on an axial end face of the valve body, in particular a radially outwardly projecting portion of the valve body; and / or the retaining cap has a wall which radially surrounds and / or is attached to a portion of the base body; and / or a portion of the valve body extends through the opening.

[0014] According to one embodiment, the base body has a, in particular pot-like, section with a base body base in which the inlet opening is provided and / or with a wall section which radially surrounds a further section of the valve body.

[0015] According to one embodiment, the further prestressing element has a first end which is supported on a region of the base body base surrounding the inlet opening, and a second end which is supported on a region of the valve element surrounding the through-opening of the valve element and facing the base body base.

[0016] According to one embodiment, the biasing element has a first end supported on a valve plate of the valve member and a second end supported on a radially inwardly extending portion of an inner wall of the valve body.

[0017] According to one embodiment, the valve element is at least partially accommodated in a receiving space of the valve body.

[0018] According to one embodiment, an inner wall of the receiving space has a radially inwardly extending portion which is designed to limit the axial displacement of the valve element in the direction of the outlet opening relative to the valve body.

[0019] In one embodiment, this can further contribute to preventing damage to the check valve.

[0020] According to one embodiment, the check valve is designed so that, when used as intended, in an open position of the check valve, a fluid flows sequentially through the inlet opening, the through opening, the passage and the outlet opening.

[0021] According to one embodiment of the invention, a check valve as described above is used in a fluid system, in particular of a motor vehicle.

[0022] The check valve can be used in a fluid system to clean a sensor using a fluid.

[0023] Further advantages and features emerge from the subclaims and the exemplary embodiments. The following shows, partly schematically: Fig. 1 a cross-sectional view of a check valve according to an embodiment in a closed position, Fig. 2 an exploded view of the Fig. 1 shown cross-sectional view of the check valve, Fig. 3 a cross-sectional view of the Fig. 1 shown check valve in a state in which a valve body together with a valve element and a valve member accommodated in the valve body, compared to the one shown in Fig. 1 shown state is shifted to the right, and Fig. 4 is a cross-sectional view of the Fig. 1 shown check valve in a state in which the valve element is in comparison to the one shown in Fig. 1 shown state is shifted to the left.

[0024] Fig. 1 shows a cross-sectional view of a check valve according to an embodiment in a closed position, and Fig. 2 shows an exploded view of the Fig. 1 shown cross-sectional view of the check valve.

[0025] The check valve 100 can be used, for example, in a fluid system (not shown), in particular in a motor vehicle, for cleaning a sensor using a fluid. Furthermore, the check valve 100 can be used in a fluid system in which the fluid is or at least contains urea.

[0026] The check valve 100 comprises a housing with a base body 10 having an inlet opening 11 intended to be connected to a fluid reservoir (not shown), for example, via a supply line. A pump (not shown) is preferably arranged between the inlet opening 11 and the fluid reservoir. This pump pumps the fluid from the fluid reservoir to the inlet opening 11 as needed to create an inlet pressure of the fluid at the inlet opening 11 that depends, among other things, on the pump's power.

[0027] The check valve 100 further comprises a valve body 20 which has a passage 21 with an outlet opening 22, is arranged in sections in the base body 10 and is arranged to be axially displaceable relative to the base body 10.

[0028] In this case, the base body 10 has in particular a pot-like section with a base body base 12 in which the inlet opening 11 is provided, and a wall section 13 which radially surrounds at least one further section of the valve body 20.

[0029] The housing further comprises a pot-shaped retaining cap 15 with a wall 16 which radially surrounds a section of the base body 10 and is fastened thereto, and with a base 17 with an opening 18 through which a section of the valve body 20 extends. The fastening of the retaining cap 15 to the section of the base body 10 can be effected, for example, by means of a snap connection, in which the retaining cap 15 has at least one latching device 19, for example in the form of one or more holes, and the base body 10 has a corresponding number of latching devices 14, for example in the form of radial projections, which latch into the corresponding latching devices 19 when the retaining flap 15 is slipped over the base body 10.

[0030] In the valve body 20, at least in sections, a valve element 30 is arranged which is axially displaceable relative to the valve body 20 and has a through opening 31.

[0031] Between the outlet opening 22 and the valve element 30, a valve member 40 with a sealing element 41, which for example comprises or is formed from a rubber, a valve plate 43 on which the sealing element 41 is arranged, and a valve stem 42 is arranged, which is axially displaceable relative to the valve body 20, in particular guided by a guide section of an inner wall of the valve body 20.

[0032] The check valve 100 further comprises a biasing element 50 having a first end 51 supported on a side of the valve plate 43 of the valve member 40 facing the outlet opening 22, and a second end 52 supported, for example, on a radially inwardly extending portion of the inner wall of the valve body 20 in order to bias the valve member 40 with a biasing force in the direction of the valve element 30.

[0033] The check valve 100 also has a further prestressing element 60, which has a first end 61, which is supported on a region of the base body base 12 surrounding the inlet opening 11, and a second end 62, which is supported on a region of the valve element 30 surrounding the through-opening 31 of the valve element 30 and facing the base body base 12, in order to prestress the valve element 30 with a prestressing force of the further prestressing element 60 in the direction of the valve member 40.

[0034] In addition or alternatively to the further prestressing element 60, the check valve 100 has another prestressing element 70, which has a first end 71 supported on a region of the base 17 of the retaining cap 15 surrounding the opening 18, and a second end 72 supported on an axial end face of a radially projecting portion 23 of the valve body 20 in order to prestress the valve body 20 with a prestressing force of the other prestressing element 70 in the direction of the inlet opening 11.

[0035] The valve element 30 has a sealing seat 32 surrounding the through-opening 31, which faces the sealing element 41. In the Fig. 1 In the illustrated closed position of the check valve 100, the sealing element 41 rests against the sealing seat 32 and closes the through opening 31 when the inlet pressure generated by the pump and thus a force acting on the sealing element 41 in the direction of the outlet opening 22 is below a predetermined inlet pressure value determined by the prestressing force acting in the opposite direction.

[0036] In order to prevent the fluid from flowing from the inlet opening 11 to the outlet opening 22 in the closed position of the check valve 100, the valve body 20 is sealed radially with respect to the base body 10 and the valve element 30 is sealed radially with respect to the valve body 20, for example by further sealing elements not illustrated in the figures.

[0037] If the input pressure generated by the pump is above the predetermined input pressure value, the valve member 40 together with the sealing element 41 is displaced in the direction of the outlet opening 22 into an open position of the check valve 100 by the corresponding applied force, so that the through opening 31 is opened and the fluid flows from the inlet opening 11 via the through opening 31 and the passage 21 to the outlet opening 22.

[0038] The valve element 30 is in particular at least partially received in a receiving space of the valve body 20, wherein an inner wall of the receiving space has a radially inwardly extending portion 24 which is designed to limit the axial displacement of the valve element 30 in the direction of the outlet opening 22 relative to the valve body 20.

[0039] Fig. 3 shows a cross-sectional view of the Fig. 1 shown check valve 100 in a state in which the valve body 20 together with the valve element 30 and the valve member 40 accommodated in the valve body 20, compared to the state shown in Fig. 1 shown state is shifted to the right.

[0040] This displacement can be caused, for example, by the fluid entering through the inlet opening 11 expanding as a result of the fluid freezing in the fluid reservoir and / or the corresponding supply line to the check valve 100, and the expanding frozen / freezing fluid pushing or displacing the valve element 30 to the right in the direction of the outlet opening 22, and, as soon as a section of the valve element 30 bears against the radially inwardly extending section 24, also pushing or displacing the valve body 20 to the right in the direction of the outlet opening 22 against the prestressing force applied by the other prestressing element 70. In this case, due to the contact of the sealing seat 32 with the sealing element 41, the latter, together with the valve plate 43 and the valve stem 42, is also pushed to the right in the direction of the outlet opening 22.

[0041] Fig. 4 shows a cross-sectional view of the Fig. 1 shown check valve 100 in a state in which the valve element 30 is in comparison with the one shown in Fig. 1 shown state is shifted to the left.

[0042] This displacement can be caused, for example, by a fluid entering through the outlet opening 22 from an outlet line (not shown) of the check valve 100 expanding in the direction of the check valve 100 as a result of the fluid in the outlet line freezing, and the expanding frozen / freezing fluid pressing the valve element 30 to the left in the direction of the inlet opening 11 against the further prestressing force applied by the further prestressing element 60. Bezugszeichenliste

[0043] 10 Base body 11 Inlet opening 12 Base body base 13 Wall section 14 Latching device 15 Retaining cap 16 Wall 17 Base 18 Opening 19 Latching device 20 Valve body 21 Passage 22 Outlet opening 23 Radially outwardly projecting section 24 Radially inwardly extending section 30 Valve element 31 Passage opening 32 Sealing seat 40 Valve member 41 Sealing element 42 Valve stem 43 Valve plate 50 Preload element 51 First end of preload element 52 Second end of preload element 60 Further preload element 61 First end of further preload element 62 Second end of further preload element 70 Other preload element 71 First end of other preload element 72 Second end of other preload element 100 Check valve

Claims

1. Check valve (100), comprising: a housing having a main body (10), which has an inlet opening (11), a valve body (20), which has a passage (21) having an outlet opening (22) and which is at least partly arranged in the main body (10), a valve element (30), which is at least partly arranged in the valve body (20) for axial movement relative to the valve body (20) and which has a through-opening (31), a valve member (40), which is arranged in the valve body (20) between the outlet opening (22) and the valve element (30) and has a sealing element (41) and a valve stem (42), which is axially movable relative to the valve body (20), a preloading element (50), which is designed to preload the valve member (40) toward the valve element (30) with a preload force, wherein the check valve (100) also comprises: a further preloading element (60), which is designed to preload the valve element (30) toward the valve member (40) with a further preload force, and / or another preloading element (70), which is designed to preload the valve body (20) toward the inlet opening (11) with another preload force, wherein the valve element (30) comprises a sealing seat (32), which surrounds the through-opening (31) and faces the sealing element (41), and in a closed position of the check valve (100) the sealing element (41) abuts the sealing seat (32) and closes the through-opening (31), characterized in that the valve body (20) is axially movable relative to the main body (10).

2. Check valve (100) according to Claim 1, in which the valve body (20) is radially sealed to the main body (10) and / or the valve element (30) is radially sealed to the valve body (20).

3. Check valve (100) according to one of the preceding claims, in which the housing has a retaining cap (15), in particular a pot-like retaining cap, which has a bottom (17) with an opening (18).

4. Check valve (100) according to Claim 3, in which the other preloading element (70) has a first end (71), which is supported on a region of the bottom (17) of the retaining cap (15) surrounding the opening (18), and a second end (72), which is supported on an axial front face of the valve body (20), in particular of a radially outwardly protruding portion (23) of the valve body (20); and / or in which the retaining cap (15) has a wall (16), which radially surrounds a portion of the main body (10) and / or is fastened thereto; and / or in which a portion of the valve body (20) extends through the opening (18).

5. Check valve (100) according to one of the preceding claims, in which the main body (10) comprises a portion, in particular a pot-like portion, having a main body bottom (12), in which the inlet opening (11) is provided, and / or having a wall portion (13), which radially surrounds a further portion of the valve body (20).

6. Check valve (100) according to Claim 5, in which the further preloading element (60) has a first end (61), which is supported on a region of the main body bottom (12) surrounding the inlet opening (11), and a second end (62), which is supported on a region of the valve element (30) surrounding the through-opening (31) of the valve element (30) and facing the main body bottom (12).

7. Check valve (100) according to one of the preceding claims, in which the preloading element (50) has a first end (51), which is supported on a valve disk (43) of the valve member (40), and a second end (52), which is supported on a radially inwardly extending portion of an inner wall of the valve body (20).

8. Check valve (100) according to one of the preceding claims, in which the valve element (30) is at least partly received in a receiving space of the valve body (20).

9. Check valve (100) according to the preceding claim, in which an inner wall of the receiving space has a radially inwardly extending portion (24), which is designed to limit the axial movement of the valve element (30) toward the outlet opening (22) relative to the valve body (20).

10. Check valve (100) according to one of the preceding claims, which is designed such that, during normal use, with the check valve (100) in an open position a fluid flows sequentially through the inlet opening (11), the through-opening (31), the passage (21) and the outlet opening (22).

11. Use of a check valve (100) according to one of the preceding claims in a fluid system, in particular of a motor vehicle.

12. Use of a check valve (100) according to Claim 11, wherein the check valve (100) is used in a fluid system for cleaning a sensor by means of a fluid.