HYDRAULIC SWITCHING ASSEMBLY FOR A MOTOR VEHICLE

Abstract

A hydraulic switching assembly for a motor vehicle, having a hydraulic pump (1) which guides a hydraulic medium from a reservoir (2) via hydraulic lines (3) and at least one magnetic valve assembly (4) including a magnetically actuatable switching valve (5), to a switching element (6) in order to hydraulically actuate the switching element (6) between two switching positions. A pressure accumulator (7) and a first check valve (8a) are mounted in a supply line (3a) upstream of the switching valve (5) in order to realize a reliable temporary supply of oil pressure to the switching element (6).

Claims

1. A hydraulic switching assembly for a motor vehicle, the hydraulic switching assembly comprising: a hydraulic pump that is adapted to feed a hydraulic medium from a sump via hydraulic lines; a magnetic valve assembly with a magnetically actuatable switching valve by which the hydraulic medium is adapted to be fed via the hydraulic lines to a switching element in order to hydraulically actuate the switching element between two switching positions; and, a pressure accumulator and a first check valve arranged in a feed line upstream of the switching valve that are adapted to provide a, temporary supply of oil pressure to the switching element.

2. The switching assembly according to claim 1, wherein the pressure accumulator and the first check valve are integrated in the magnetic valve assembly.

3. The switching assembly according to claim 1, wherein the pressure accumulator is constructed as a membrane accumulator, gas accumulator, or piston accumulator.

4. The switching assembly according to claim 1, further comprising a throttle valve arranged in a bypass line upstream of the first check valve that allows a flushing of the hydraulic lines via a run-back line of the switching valve that leads to the sump.

5. The switching assembly according to claim 4, further comprising a second check valve arranged in the bypass line downstream of the throttle valve.

6. The switching assembly according to claim 5, wherein the bypass line is integrated in the magnetic valve assembly.

7. The switching assembly according to claim 4, further comprising a first pressure limiting valve arranged in the run-back line of the switching valve that sets a pressure for the flushing of the hydraulic lines.

8. The switching assembly according to claim 1, further comprising a second pressure limiting valve arranged in a pressure-relief line that leads to the sump downstream of the hydraulic pump.

9. The switching assembly according to claim 1, further comprising a filter device that cleans the hydraulic medium located downstream of the hydraulic pump.

10. The switching assembly according to claim 1, further comprising a cooling device that cools the hydraulic medium located downstream of the hydraulic pump.

11. A hydraulic switching assembly, comprising: a magnetic valve assembly with a magnetically actuatable switching valve; a hydraulic pump that is adapted to feed a hydraulic medium from a sump via hydraulic lines and the magnetic valve assembly to a switching element in order to hydraulically actuate the switching element between two switching positions; a first check valve arranged in a feed line upstream of the switching valve; and a pressure accumulator arranged in the feed line downstream of the check valve and upstream of the switching valve that supplies a temporary supply of oil pressure to the switching element.

12. The switching assembly according to claim 11, wherein the pressure accumulator and the first check valve are integrated in the magnetic valve assembly.

13. The switching assembly according to claim 1, wherein the pressure accumulator is constructed as a membrane accumulator, gas accumulator, or piston accumulator.

14. The switching assembly according to claim 11, further comprising a throttle valve arranged in a bypass line upstream of the first check valve that allows a flushing of the hydraulic lines via a run-back line of the switching valve that leads to the sump.

15. The switching assembly according to claim 14, further comprising a second check valve arranged in the bypass line downstream of the throttle valve.

16. The switching assembly according to claim 15, wherein the bypass line is integrated in the magnetic valve assembly.

17. The switching assembly according to claim 14, further comprising a first pressure limiting valve arranged in the run-back line of the switching valve that sets a pressure for the flushing of the hydraulic lines.

18. The switching assembly according to claim 11, further comprising a second pressure limiting valve arranged in a pressure-relief line that leads to the sump downstream of the hydraulic pump.

19. The switching assembly according to claim 11, further comprising a filter that cleans the hydraulic medium located downstream of the hydraulic pump.

20. The switching assembly according to claim 11, further comprising a cooling device that cools the hydraulic medium located downstream of the hydraulic pump.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Additional measures relating to the invention are described in more detail below together with the description of three preferred embodiments of the invention with reference to the figures. Shown are:

[0015] FIG. 1 a schematic view for illustrating the setup of the hydraulic switching assembly according to the invention according to a first embodiment,

[0016] FIG. 2 a schematic view for illustrating the setup of the hydraulic switching assembly according to the invention according to a second embodiment,

[0017] FIG. 3 a schematic view for illustrating the setup of the hydraulic switching assembly according to the invention according to a third embodiment.

DETAILED DESCRIPTION

[0018] According to FIGS. 1, 2, and 3, a hydraulic switching assembly according to the invention for a motor vehiclenot shown herehas a hydraulic pump 1 that feeds a hydraulic medium from a sump 2 via hydraulic lines 3. In particular, the hydraulic medium is motor oil of the motor vehicle. The motor oil is fed via the hydraulic pump 1 through a filter device 11 for cleaning the motor oil and through a cooling device 12 for cooling the motor oil to a magnetic valve assembly 4. A pressuring limiting valve 10b is arranged in a pressure-relief line 3d leading to the sump 2 downstream of the hydraulic pump 1 and upstream of the filter device 11. When a preset oil pressure in the line section between the pump 1 and the filter device 11 is exceeded, the pressure limiting valve 10b opens and enables the return of motor oil into the sump 2 via the pressure-relief line 3d.

[0019] The magnetic valve assembly 4 has a magnetically actuatable switching valve 5 that is constructed as a 3/2-way directional control switching valve. A first check valve 8a is arranged in a feed line 3a of the switching valve 5. A pressure accumulator 7 is arranged between the first check valve 8a and the switching valve 5. The pressure accumulator 7 is connected with a fluid connection to the switching valve 5 via the feed line 3a of the switching valve 5. Furthermore, the pressure accumulator 7 and the first check valve 8a are integrated in the magnetic valve assembly 4. The switching valve 5 is connected to the switching element 6 via a work line 3e, in order to hydraulically actuate the switching element 6 between two switching positions.

[0020] The switching valve 5 has a first and second switching position 13a, 13b, wherein, in the first switching position 13a of the switching valve 5, a flow of the motor oil to the switching element 6 is blocked and thus the switching element 6 is not hydraulically actuated. For a magnetic actuation of the switching valve 5, a fluid connection between the pressure accumulator 7 and the switching element 6 is established by the switching valve 5, in order to realize a reliable temporary supply of oil pressure to the switching element 6 and to hydraulically actuate the switching element 6.

[0021] According to FIG. 1, the pressure accumulator 7 is constructed as a membrane accumulator 7a. A throttle valve 9 is arranged in a bypass line 3b upstream of the first check valve 8a, in order to realize a flushing of the hydraulic lines 3 by the use of a run-back line 3c of the switching valve 5 leading to the sump 2. A pressure limiting valve 10a is arranged in the run-back line 3c of the switching valve 5, in order to set a pressure during flushing of the hydraulic lines 3. The flushing of the hydraulic lines 3 and especially also the flushing of the switching gallery are performed in the illustrated first switching position 13a of the switching valve 5. Furthermore, a second check valve 8b is arranged in the bypass line 3b downstream of the throttle valve 9. The second check valve 8b is provided to prevent leakage via the throttle valve 9 during the actuation of the switching element 6 by the switching valve 5 located in the second switching position 13b.

[0022] According to FIG. 2, the pressure accumulator 7 is constructed as a gas accumulator 7b. In contrast to the embodiment from FIG. 1, the bypass line 3b is integrated in the magnetic valve assembly 4 in the embodiment according to FIG. 2. Thus, the throttle valve 9 and the second check valve 8b are also located in the magnetic valve assembly 4. The pressure limiting valve 10a arranged in the run-back line 3c sets the hydraulic pressure for flushing of the hydraulic lines 3.

[0023] According to FIG. 3, the pressure accumulator 7 is constructed as a piston accumulator 7c. The bypass line 3b is connected directly to the run-back line 3c leading to the sump 2 in contrast to the respective bypass line 3b according to the first and second embodiment. A throttle valve 9 for flushing the hydraulic lines 3 is arranged in the bypass line 3b. The pressure for flushing the hydraulic lines 3 is set by the first pressure limiting valve 10a in the run-back line 3c.

List of Reference Symbols

[0024] 1 Pump

[0025] 2 Sump

[0026] 3 Lines

[0027] 3a Feed line

[0028] 3b Bypass line

[0029] 3c Run-back line

[0030] 3d Pressure-relief line

[0031] 3e Work line

[0032] 4 Magnetic valve assembly

[0033] 5 Switching valve

[0034] 6 Switching element

[0035] 7 Pressure accumulator

[0036] 7a Membrane accumulator

[0037] 7b Gas accumulator

[0038] 7c Piston accumulator

[0039] 8a, 8b Check valve

[0040] 9 Throttle valve

[0041] 10a, 10b Pressure limiting valve

[0042] 11 Filter device

[0043] 12 Cooling device

[0044] 13a, 13b Switching position