Spring-loaded check valve for hydraulic assisted vehicle brake equipment and assisted vehicle brake equipment with check valve

Abstract

The invention proposes a check valve (1) for a hydraulic assisted vehicle brake system with a hole disc-shaped valve seat part (9), to which a valve housing (12) is pressed, in which a valve ball as a shut-off body (10) and a helical compression spring as a valve spring (11) are arranged. A bowl-shaped filter (14) is fastened in a recess (16) of the valve seat part (8) relative to the valve housing (12).

Description

Technical Field

[0001] The present invention relates to a spring-loaded check valve for a hydraulic power-assisted vehicle braking system having the features of the preamble of claim 1, and a hydraulic block for a hydraulic unit of a hydraulic power-assisted vehicle braking system with a check valve having the features of the preamble of claim 8. Background Technology

[0002] Patent DE 42 36 481 C2 discloses a check valve comprising a ball serving as a stop body; a rotationally symmetrical valve seat having an axially through-hole with a hollow frustoconical valve seat at the opening of the through-hole; a valve spring loading the stop body toward the valve seat; and a valve housing in which the stop body and the valve spring are arranged and supported. A known check valve has a valve housing that is a plate piece with a disc-shaped bottom and three axially parallel arms, the valve spring being supported at the bottom. The arms extend from the bottom of the valve housing to the valve seat outside the valve spring and outside the stop body at their periphery. The arms of the valve housing are T-shaped at their free ends and elastically fit into an circumferential groove on the outer periphery of the valve seat. A cylindrical receiving portion in a hydraulic block retains the T-shaped ends of the arms of the valve housing within the circumferential groove of the valve seat. Summary of the Invention

[0003] The check valve according to the invention is provided for hydraulic power-assisted vehicle braking equipment, where the check valve is arranged, for example, between the brake fluid reservoir and the piston cylinder unit of the power-assisted braking pressure generator, or between the brake fluid reservoir and the hydraulic pump / return pump of the sliding adjustment unit.

[0004] The check valve according to the invention includes a valve seat component with a valve seat, a stop body, a valve spring that loads the stop body toward the valve seat, and a valve housing. The valve housing is disposed at the valve seat component, and the stop body and the valve spring are disposed within the valve housing. The valve seat is a sealing surface surrounding the fluid penetration portion of the check valve, and the stop body abuts against the sealing surface when the valve is closed to prevent fluid penetration in the flow direction within the check valve. When the check valve is open, the stop body disengages from the valve seat, allowing fluid to flow through the fluid penetration portion of the check valve. The valve housing is hollow and can also have a large-area opening, and the valve housing fixes the stop body in the open state such that the stop body returns to the valve seat when the check valve is closed. Furthermore, the valve housing retains the valve spring.

[0005] The check valve according to the invention has a valve seat component with a protrusion and a valve body with an annular shoulder that transitions into a tubular flange at its outer periphery. The annular shoulder of the valve body abuts against the end face of the protrusion of the valve seat component, and the flange is press-fitted with the circumferential surface of the protrusion of the valve seat component, thereby connecting the valve body and the valve seat component.

[0006] The check valve according to the present invention constitutes a structural component that can be pre-assembled and whose function can be tested before installation.

[0007] The dependent claims concern improvements and advantageous designs of the invention as described in the independent claims.

[0008] All the features disclosed in the specification and drawings can be implemented individually or in virtually any combination in embodiments of the invention. Embodiments of the invention that do not possess all of the features of the claims, but only one or more of the features, are generally feasible. Attached Figure Description

[0009] The present invention will be described in more detail below with reference to embodiments shown in the accompanying drawings. Wherein: Figure 1 An axial section of the check valve according to the invention is shown; and Figure 2 Showing with from Figure 1 A partial diagram of the hydraulic circuit of the hydraulic power-assisted vehicle braking system with the aforementioned check valve. Detailed Implementation

[0010] exist Figure 1 The spring-loaded check valve 1 shown according to the invention is provided for a hydraulically powered vehicle braking device 2, and is arranged therein, particularly between the unpressurized brake fluid reservoir 3 and the cylinder 4 of the piston cylinder unit 5 of the power-assisted brake pressure generator 6, or between the unpressurized brake fluid reservoir 3 and the suction side of the hydraulic pump 7 of the sliding adjustment part of the vehicle braking device 2.

[0011] The check valve 1 includes a valve seat part 8 with a valve seat 9, a stop body 10, a valve spring 11, a valve housing 12, and a filter 14. The valve seat part 8 has an axial through-hole 13 serving as a fluid penetration portion, the through-hole leading to an end side of the valve seat part 8 with a hollow frustoconical sealing surface, the sealing surface constituting the valve seat 9. In an embodiment, the valve seat part 8 is relatively short axially, its axial height being approximately one-third of its diameter. The valve seat part has a stepped diameter at its outer periphery, its outer diameter decreasing towards the end side where the valve seat 9 is located. A smaller diameter axial section on the side of the valve seat 9 constitutes a protrusion 15 of the valve seat part 8. For cost reasons, the valve seat part is a molded part, particularly a solid molded part, manufactured, for example by forging or stamping. Other manufacturing methods are not excluded by this invention.

[0012] On the end opposite to the valve seat 9, the valve seat part 8 has a columnar recess 16 with a stepped diameter, and the through hole 13 leads to the bottom of the recess.

[0013] In this embodiment, the filter 14 is a bowl-shaped hollow body made of silk fabric, with its bottom arched into the filter 14. The surrounding edge of the filter 14 is formed into a ring-shaped fastening flange 17, and a plastic ring serving as a support 46 is injection-molded from the hollow side of the filter 14 onto the fastening flange. Using the support, the filter 14 is placed on the bottom of the recess 16 of the valve seat part 8. The surrounding stamped portion 45, which overlaps the support 46 of the filter 14, holds the filter in the recess 16 of the valve seat part 8. The hollow side of the filter 14 faces the bottom of the recess 16.

[0014] The stop body 10 in this embodiment is a sphere made of steel, other metals, or plastic. Other forms of stop bodies and, if necessary, a valve seat 9 (not shown) may also be used.

[0015] In this embodiment, the valve spring 11 is a helical compression spring, which is arranged coaxially with the valve seat part 8, the valve seat 9, and the stop body 10, and the helical compression spring loads the stop body 10 toward the valve seat 9. The valve seat 9 is, as described, a sealing surface against which the stop body 10 abuts when the check valve 1 is closed, thereby blocking the axial through hole 13 forming the fluid penetration portion in the valve seat part 8 and thus blocking the check valve 1 to prevent fluid penetration. The check valve 1 is opened by a pressure difference that is much greater on the side of the filter 14 than on the opposite side, such that the pressure difference overcomes the spring force of the valve spring 11 and disengages the stop body from the valve seat 9.

[0016] The valve housing 12 is a tubular part having diameters varying along its axial length. In one embodiment, the valve housing 12 is deep-drawn from sheet metal; however, other materials and / or manufacturing types are feasible. At the end facing the valve seat part 8, the valve housing 12 has an annular shoulder 18, which transitions at its outer periphery into a shorter, cylindrical flange 19 along the axial direction. The flange 19 has an inner diameter slightly smaller than the outer diameter of the protrusion 15 of the valve seat part 8, and the flange 19 of the valve housing 12 surrounds the protrusion 15 of the valve seat part 8 by press fit, thereby retaining the valve housing 12 at the valve seat part 8. The annular shoulder 18 of the valve housing 12 abuts against the end face of the protrusion 15 of the valve seat part 8.

[0017] The annular shoulder 18 of the valve housing 12 transitions into a first cylindrical section 20 at its inner circumference. The inner diameter of this section is larger than the diameter of the stop body 10, allowing fluid to flow through the stop body 10 via an axial through-hole 13 in the valve seat component 8 when the check valve 1 is open. At a short axial distance from the annular shoulder 18, the first cylindrical section 20 of the valve housing 12 has a large through-opening 21 for the fluid to flow through the check valve 1. This through-opening 21 occupies more than half, and preferably at least 2 / 3 or 3 / 4, of the circumference of the first cylindrical section 20. The axial distance of the through-opening 21 from the annular shoulder 18 is less than 1 / 10 of the diameter of the first cylindrical section 20 and less than the maximum stroke of the stop body 10, referring to the maximum distance between the stop body 10 and the valve seat 9 when the check valve 1 is open. Thus, with the check valve 1 open, the fluid does not need to flow around the stop body 10, but can flow out through the stop body and through the penetration opening 21 with little flow resistance.

[0018] The valve housing 12 has axially parallel tabs 22 between the penetration openings 21, and axially parallel sickes 23 are formed inward at the tabs, the sickes guiding the stop body 10 axially.

[0019] At the end of the first cylindrical section 20, away from the annular shoulder 18, the valve housing 12 tapers in an embodiment into a smaller diameter second cylindrical section 24, which forms a perforated cage bottom 25 at its end away from the flange 19, on which the valve spring 11 is supported. The smaller diameter second cylindrical section 24 of the valve housing 12 guides the valve spring 11 and supports it to prevent lateral bending. The contraction 42 of the valve housing 12 constitutes a stroke limiting portion, which limits the stroke, that is, the distance from the valve seat 9 to the stop body 10. The contraction 42 need not be tapered, but can also be implemented, for example, as a radial annular shoulder (not shown).

[0020] According to the invention, the check valve 1 is implemented as a pre-assembled structural assembly. Before the check valve 1 is inserted into the check valve receiving portion 26 of the hydraulic block 27, the individual parts of the check valve, the valve seat part 8, can be assembled on one side with the filter 14 and on the other side with the valve housing 12—the stop body 10 and the valve spring 11 are arranged in the valve housing—and can be functionally tested. The filter 14 prevents chips, abrasives, dirt, etc., that occur during subsequent processing steps and / or assembly from falling through the through hole 13 of the valve seat part 8 onto the stop body 10 and reaching the valve seat 9.

[0021] The check valve 1 is arranged in the check valve receiving portion 26 of the hydraulic block 27 according to the invention, wherein, in Figure 1 The area surrounding the check valve 1 is shown. The hydraulic block 27 is a square metal block with a receiving portion for hydraulic components of the vehicle braking device 2 and its sliding adjustment portion, such as the power assist brake pressure generator 6, the hydraulic pump 7, and the solenoid valve. These components are arranged in the receiving portion of the hydraulic block 27 and connected to each other via holes in the hydraulic block 27 according to the hydraulic wiring diagram of the vehicle braking device 2. The hydraulic block 27 constitutes the hydraulic assembly of the power assist vehicle braking device 2 or its sliding adjustment portion, equipped with hydraulic components. Such hydraulic blocks 27 and hydraulic assemblies for hydraulic power assist vehicle braking devices and their sliding adjustment portions are known and will not be further described here.

[0022] The hydraulic block 27, referred to herein as the upper side 28, has a stepped-diameter hole in its side portion into which a connection joint 29 of a pressureless brake fluid reservoir 3 extends. The brake fluid reservoir 3 is arranged on the upper side 28 of the hydraulic block 27, and wherein... Figure 1Only the section at the bottom of the container is shown. The connection joint 29 is sealed using an O-ring 30 in a hole in the hydraulic block 27.

[0023] Below the connecting joint 29, the check valve 1 is arranged in the hole, wherein the annular shoulder of the valve seat part 8 surrounding the protrusion 15 of the valve seat part 8 is axially positioned on the annular step surrounding the hole in the hydraulic block 27. A guide hole 31 is guided from the bottom of the hole in the hydraulic block 27 to, for example, the cylinder 4 of the piston cylinder unit 5 of the power-assisted brake pressure generator 6. The hole in which the check valve 1 is arranged, or a portion thereof, constitutes a check valve receiving portion 26 in the hydraulic block 27.

[0024] The diameter of the check valve 1 or the valve seat part 8—at which the check valve 1 has its largest outer diameter—is smaller than the diameter of the connecting joint 29 of the brake fluid reservoir 3, which has a diameter of 17 mm. The check valve 1 and the connecting joint 29 are coaxially arranged in a stepped-diameter bore in the hydraulic block 27 and are pressure-sealed within the bore using a tubular punch (not shown). During punching, the punch is centered within the hydraulic block 27 in the bore or at the opening of the bore.

[0025] Figure 2 A simplified partial view of the hydraulic circuit diagram of a hydraulic power-assisted vehicle braking system 2 is shown, in which a check valve 1 according to the invention is applied. The vehicle braking system 2 has a master brake cylinder 32 and a power-assisted braking pressure generator 6 that can be operated by muscle force via a foot brake pedal 41 or by a handbrake lever (not shown). One or more braking circuits (denoted as a single braking circuit) of the vehicle braking system 2 are hydraulically connected in parallel to them.

[0026] The assisted braking pressure generator 6, as described above, has a piston-cylinder unit 5. The piston 33 of this unit can move within the cylinder 4 of the piston-cylinder unit 5 via a threaded drive 35 with the assistance of an electric motor 34 to generate braking pressure. A mechanical reduction gear mechanism, such as a planetary gear mechanism, can be arranged between the electric motor 34 and the threaded drive 35. Other assisted braking pressure generators 6, such as those with a hydraulic pump (not shown), are also feasible.

[0027] One or more braking circuits of the vehicle braking device 2 are hydraulically connected in parallel to the master brake cylinder 32 through the respective separation valves 36 of each braking circuit, and are connected to the cylinder 4 of the piston cylinder unit 5 of the power assist brake pressure generator 6 through the respective assist valves 37 of each braking circuit, or are generally connected to the power assist brake pressure generator 6.

[0028] One or more hydraulic wheel brakes 38 are connected to various brake circuits of the vehicle braking system 2, wherein each wheel brake 38 is connected to a corresponding brake circuit via an inlet valve and an outlet valve for individualized braking pressure adjustment of the wheel. Figure 2 In this process, the inlet valve and the outlet valve are combined to form a wheel brake pressure regulating valve device 39.

[0029] The cylinder 4 of the piston cylinder unit 5 of the power-assisted brake pressure generator 6 is connected to the brake fluid reservoir 3 via a brake line 40 and, additionally, hydraulically in parallel via a check valve 1 according to the invention. The brake line 40 is connected to the cylinder 4 such that the piston 33 passes over and thereby blocks the brake line at the beginning of its stroke. The check valve 1 allows flow from the brake fluid reservoir 3 toward the cylinder 4 of the piston cylinder unit 5 of the power-assisted brake pressure generator 6. The connection between the cylinder 4 of the piston cylinder unit 5 of the power-assisted brake pressure generator 6 and the brake fluid reservoir 3 via the check valve 1 according to the invention is always present, so that when a negative pressure exists in the cylinder 4 relative to the unpressurized brake fluid reservoir 3, the power-assisted brake pressure generator 6 draws brake fluid into the cylinder 4 during the return stroke of the piston 33.

[0030] The braking pressure used for operational braking is generated by the booster brake pressure generator 6 and regulated by the reciprocating motion of the piston 33 and / or by the wheel brake pressure regulating valve device 39. Here, one or more booster valves 37 are opened, thereby hydraulically connecting one or more brake circuits of the vehicle braking system 2 to the booster brake pressure generator 6. One or more release valves 36 are closed during operational braking, thereby hydraulically disengaging the master brake cylinder 32 from the brake circuit. The master brake cylinder functions as a target value transmitter during operational braking, used to generate the desired braking pressure using the booster brake pressure generator 6.

[0031] In the event of a malfunction in the power assist braking pressure generator 6, auxiliary braking can be achieved by using muscle force through the main brake cylinder 32.

[0032] Slip adjustment can be achieved using the inlet and outlet valves of the wheel brake pressure regulating valve device 39 and the power assist brake pressure generator 6. Such slip adjustment can be anti-lock braking system (ABS), drive slip adjustment, and / or ride dynamics adjustment, or electronic stability program (ESP), commonly referred to as ABS, ASR, and / or FDR or ESP. Such slip adjustment is known and will not be elaborated upon here.

[0033] For sliding adjustment, the vehicle braking system may additionally include hydraulic pumps 7 in each braking circuit, which can be driven together with electric motors 42. One or more hydraulic pumps 7 deliver brake fluid to the wheel brakes 38 and / or back to the master brake cylinder 32 during sliding adjustment. This is also known and will not be further elaborated here.

[0034] One or more hydraulic pumps 7 can be used to assist in pressure build-up in the event of a failure of the power-assisted brake pressure generator 6. With one or more hydraulic pumps 7 present, the check valve 1 between the brake fluid storage container 3 and the cylinder 4 of the power-assisted brake pressure generator 6 can be omitted.

[0035] In addition to the foot brake pedal 41 and the wheel brakes 38, the hydraulic components of the power-assisted vehicle braking system 2 are housed in and at the hydraulic block 27 according to the invention. Specifically, the check valve 1, the piston cylinder unit 5 of the power-assisted brake pressure generator 6, the one or more hydraulic pumps 7, the one or more disconnect valves 36, the one or more power-assisted valves 37, and the inlet and outlet valves of the wheel brake pressure regulating valve device 39 are arranged in the receiving portion of the hydraulic block 27. The electric motor 34 of the power-assisted brake pressure generator 6, the electric motor 42 for the one or more hydraulic pumps 7, and the foot brake pedal 41 are externally arranged at the hydraulic block 27, and the brake fluid storage container 3 is placed on the upper side 28 of the hydraulic block 27.

Claims

1. A spring-loaded check valve for use in hydraulically powered vehicle braking systems, wherein, The check valve (1) has a valve seat part (8) with a valve seat (9), a stop body (10), a valve spring (11) loading the stop body (10) toward the valve seat (9), and a valve housing (12) arranged at the valve seat part (8), wherein the stop body (10) and the valve spring (11) are arranged in the valve housing (12) and the valve housing (12) supports the valve spring (11). The valve seat part (8) has a protrusion (15) and the valve housing (12) has an annular shape. Shoulder (18), the annular shoulder (18) abuts against the end face of the protrusion (15) and the annular shoulder (18) transforms into a tubular flange (19) at its outer periphery, the flange (19) having a press fit with the circumferential surface of the protrusion (15), wherein the first columnar tubular section (20) of the valve housing (12) has a through opening (21) for fluid to flow through the check valve (1), the through opening extending along the travel direction of the stop body (10) until approaching its annular shoulder (18).

2. The check valve according to claim 1, characterized in that, The valve housing (12) has a contraction portion (44) on the side of the stop body (10) opposite to the valve seat (9), the contraction portion (44) serving as a stroke limit for the stop body (10).

3. The check valve according to claim 1 or 2, characterized in that, The valve housing (12) has a rolled edge (23) extending along the travel direction of the stop body (10), the rolled edge (23) guiding the stop body (10) along the travel direction.

4. The check valve according to claim 1 or 2, characterized in that, The valve body (12) is a deep-drawn part.

5. The check valve according to claim 1 or 2, characterized in that, The valve seat part (8) is a molded part.

6. The check valve according to claim 1 or 2, characterized in that, The check valve (1) has a filter (14) on the side of the valve seat part (8) away from the valve body (12).

7. The check valve according to claim 6, characterized in that, The filter (14) is bowl-shaped and / or has a fastening flange (17) arranged in the recess (16) of the valve seat part (8).

8. The check valve according to claim 1 or 2, characterized in that, The check valve (1) is constructed as a pre-assembled structural component.

9. A hydraulic block for a hydraulic unit of a hydraulically powered vehicle braking system, said hydraulic block having a check valve according to any one of claims 1 to 8, characterized in that, The hydraulic block (27) has a recess that serves as a check valve receiving portion (26), the recess having an annular step, and the valve seat part (8) abuts against the annular step outside its protrusion (15).

10. The hydraulic block according to claim 9, characterized in that, The check valve (1) is concentrically arranged in the check valve housing (26).

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