Filter element with bypass valve

Abstract

The utility model discloses a filter element with a bypass valve, and aims to overcome the defects that an existing filter element applied to a railway vehicle braking system unit is insufficient in reliability and poor in compactness. The upper end cover and the lower end cover are fixedly connected to the two ends of the filter screen, the elastic piece, the bypass valve structure and the framework are arranged in the filter screen, the elastic piece comprises a fixed spring seat, a compression spring and a free spring seat, and oil passing holes are formed in the upper end cover and the lower end cover. The bypass valve structure comprises an inner hole shoulder arranged at the opening of the oil passing hole of the lower end cover and a valve bead arranged between the inner hole shoulder and the free spring seat; when the medium pressure of the valve bead at the oil passing hole of the lower end cover is larger than the sum of the medium pressure in the filter screen and the pre-pressure of the elastic piece on the valve bead, the valve bead is separated from the inner hole shoulder, so that the oil passing hole of the lower end cover and the oil passing hole of the upper end cover are in a communicated state, and normal work of the hydraulic brake control unit can be guaranteed. And the structure compactness requirement of the hydraulic brake control unit is met.

Description

Technical Field

[0001] The utility model relates to the field of valve bodies, and more specifically, to a filter element with a bypass valve. Background Art

[0002] The rail vehicle is braked by a hydraulic brake caliper, which controls the brake caliper to brake or release by adjusting the oil pressure.

[0003] The filter element in the hydraulic brake control unit cleans the oil in the hydraulic system and removes dirt, preventing impurities in the hydraulic brake control unit from being transferred with the liquid oil to other components of the hydraulic brake control unit and causing damage to the components.

[0004] Some existing filter elements used in hydraulic brake control units do not have bypass valves, while others have bypass valves but use face-to-face sealing, which cannot guarantee the normal operation of the hydraulic brake control unit. Once the filter element of the former is clogged, the motor pump of the hydraulic brake control unit will be overloaded or there will be no pressure oil output, and the parts will dry burn. The sealing part of the latter is easily affected by the processing technology and oil cleanliness, and the bypass valve is prone to failure.

[0005] In order to reduce the failure of the hydraulic brake control unit, ensure the normal operation of the hydraulic brake control unit, and meet the structural compactness requirements of the hydraulic brake control unit, a small and reliable filter element with a bypass valve is urgently needed. Summary of the invention

[0006] The utility model overcomes the shortcomings of insufficient reliability and poor compactness of existing filter elements used in rail vehicle brake system units, and provides a filter element with a bypass valve, which can ensure the normal operation of the hydraulic brake control unit and meet the structural compactness requirements of the hydraulic brake control unit.

[0007] In order to solve the above technical problems, the utility model adopts the following technical solutions:

[0008] A filter element with a bypass valve comprises a hollow filter screen, an upper end cover and a lower end cover fixedly connected to both ends of the filter screen, an elastic member arranged in the filter screen, a bypass valve structure and a frame, the elastic member comprises a fixed spring seat, a compression spring and a free spring seat, the upper end cover and the lower end cover are provided with oil holes, the bypass valve structure comprises an inner hole shoulder arranged at the orifice of the oil hole of the lower end cover and a valve ball between the inner hole shoulder and the free spring seat, the valve ball is separated from the inner hole shoulder when the medium pressure at the oil hole of the lower end cover is greater than the sum of the medium pressure inside the filter screen and the pre-pressure of the elastic member on the valve ball, so that the oil hole of the lower end cover and the oil hole of the upper end cover are in a connected state.

[0009] The filter element of the present application takes into account both compactness and reliability. Compactness means that the overall volume of the device only has the necessary upper end cover and lower end cover in the length direction compared to the functional filter screen, and the remaining components are all built into the filter screen. Reliability means that the present application adopts the line-surface matching method of the inner hole step and the valve ball, which can fully ensure the sealing of the valve ball to the oil hole corresponding to the lower end cover. When the oil pressure inside the filter screen is normal, the valve ball cannot be pushed open to enable the two ends of the filter element (the oil hole of the lower end cover and the oil hole of the upper end cover) to achieve passage. Specifically, the skeleton serves as a rigid structure to support the filter screen; the elastic member fixedly connected to the skeleton at one end exerts an elastic force on the valve ball in the bypass valve structure, so that it is pressed onto the inner hole shoulder of the oil hole opening of the lower end cover. The diameter of the valve ball is larger than the inner diameter of the inner hole shoulder, realizing line-surface sealing. One side of the valve ball will be subject to the pressure generated by the oil pressure at the oil hole of the lower end cover, and the other side will be subject to the sum of the oil pressure inside the filter and the elastic force generated by the elastic part. When the filter works normally, the latter will be greater than the former, thus pressing the valve ball on the inner hole shoulder to achieve sealing. However, when the filter is blocked and fails, the internal oil pressure drops to a preset level, making the sum of the latter force less than the former, then the seal will fail, and the pressure oil connected to the lower end cover will enter the inside of the filter, ensuring the normal operation of the hydraulic brake control unit. The movement of the oil in the auxiliary oil tank transmits signals to the whole machine control system through the sensor, notifying the machine section for maintenance.

[0010] Preferably, the skeleton is a cylinder with open ends and a plurality of openings on the surface, and the two ends of the skeleton are respectively abutted between the upper end cover and the lower end cover. The skeleton is open at both ends to allow oil to pass through. The openings arranged on the surface allow oil to enter the skeleton. The skeleton is directly connected to the upper end cover and the lower end cover to bear the axial pressure on the filter element and prevent the filter from being crushed by force.

[0011] Preferably, the fixed spring seat has a positioning shoulder and a fixing frame for positioning the compression spring, and the fixing frame extends in a radial direction and is inserted into the opening of the frame. The fixed spring seat reuses the opening of the frame as a positioning structure to achieve relative fixation with the frame.

[0012] Preferably, the top of the free spring seat has a positioning shoulder for positioning the compression spring, and the bottom of the free spring seat is provided with an arc-shaped groove for positioning the valve ball. The arc-shaped groove of the free spring seat plays a guiding role in positioning the valve ball, thereby preventing the valve ball from separating from the free spring seat.

[0013] As a preferred method, the filter screen is produced by sintering felt process, which can not only produce different filtering precisions according to needs, but also avoid the shedding of copper powder particles produced by sintering copper process. In addition, in terms of pollution holding capacity, sintering felt is superior to stainless steel wire mesh and sintering copper.

[0014] Preferably, the oil hole of the lower end cover is provided with an internal thread away from the hole of the upper end cover. The internal thread of the oil hole can be conveniently used for disassembly of the filter element.

[0015] Preferably, the upper end cover and the lower end cover are provided with an annular mounting groove, and the filter screen and the frame are inserted into the mounting groove. The embodiment provides positioning for the filter screen and facilitates simplified assembly.

[0016] Preferably, the side wall of the filter screen is in contact with the outer side wall of the mounting groove.

[0017] Preferably, the upper end cover and the lower end cover are fixedly connected to the filter screen by bonding.

[0018] Preferably, the side wall of the upper end cover is provided with a mounting ring groove, and a sealing ring is provided in the mounting ring groove. The structure improves the sealing performance between the upper end cover and other components.

[0019] Compared with the prior art, the beneficial effects of the utility model are:

[0020] The device only has upper and lower end covers in the axial direction outside the filter screen, and the bypass valve structure is completely built into the filter screen, which has good compactness;

[0021] The device adopts the line-surface matching method for sealing, and has high reliability. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a schematic diagram of the utility model;

[0023] In the figure:

[0024] Filter 1, upper end cover 2, lower end cover 3, frame 4, fixed spring seat 5, free spring seat 6, compression spring 7, oil hole 8, valve ball 9, inner hole shoulder 10, positioning shoulder 11, fixing frame 12, arc groove 13, internal thread 14, installation groove 15, installation ring groove 16, sealing ring 17. DETAILED DESCRIPTION

[0025] The present disclosure is further described below in conjunction with the accompanying drawings and embodiments.

[0026] It should be noted that the following detailed descriptions are illustrative and are intended to provide further explanation of the present application. Unless otherwise specified, all technical and scientific terms used herein have the same meanings as those commonly understood by those skilled in the art to which the present application belongs.

[0027] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0028] In the present disclosure, terms such as "upper", "lower", "left", "right", "front", "back", "vertical", "horizontal", "side", "bottom" and the like indicating directions or positional relationships are based on the directions or positional relationships shown in the accompanying drawings. They are relational words determined only for the convenience of describing the structural relationships of the various parts or elements of the present disclosure, and do not specifically refer to any part or element in the present disclosure and should not be understood as limitations on the present disclosure.

[0029] In the present disclosure, terms such as "fixed connection", "connected", "connection", etc. should be understood in a broad sense, indicating that it can be fixedly connected, integrally connected or detachably connected; it can be directly connected or indirectly connected through an intermediate medium. For relevant scientific research or technical personnel in this field, the specific meanings of the above terms in the present disclosure can be determined according to specific circumstances, and they cannot be understood as limitations on the present disclosure.

[0030] Example:

[0031] Ginseng Figure 1 The cross-sectional schematic diagram shown is a filter element with a bypass valve, comprising a hollow filter screen 1, an upper end cover 2 and a lower end cover 3 fixedly connected to both ends of the filter screen 1, an elastic member arranged in the filter screen 1, a bypass valve structure and a skeleton 4, the elastic member comprising a fixed spring seat 5, a compression spring 7 and a free spring seat 6, an oil hole 8 is provided on the upper end cover 2 and the lower end cover 3, the bypass valve structure comprises an inner hole shoulder 10 arranged at the orifice of the oil hole 8 of the lower end cover 3 and a valve ball 9 between the inner hole shoulder 10 and the free spring seat 6, the valve ball 9 is separated from the inner hole shoulder 10 when the medium pressure at the oil hole 8 of the lower end cover 3 is greater than the sum of the medium pressure inside the filter screen 1 and the pre-pressure of the elastic member on the valve ball 9, so that the oil hole 8 of the lower end cover 3 and the oil hole 8 of the upper end cover 2 are in a connected state.

[0032] The production process of the filter screen 1 is the sintered felt process. The sintered felt process can not only be made into different filtering accuracies according to needs, but also avoids the shedding of copper powder particles produced by the sintered copper process. In addition, in terms of pollution holding capacity, sintered felt is superior to stainless steel wire mesh and sintered copper.

[0033] The skeleton 4 is a cylinder with open ends and a plurality of openings on the surface. The two ends of the skeleton 4 are respectively abutted between the upper end cover 2 and the lower end cover 3. The skeleton 4 is open at both ends to allow oil to pass through. The openings set on the surface allow oil to enter the inside of the skeleton 4. The skeleton 4 is directly connected to the upper end cover 2 and the lower end cover 3, and bears the axial pressure on the filter element to prevent the filter 1 from being crushed by force. The openings are evenly distributed on the surface of the skeleton 4.

[0034] The fixed spring seat 5 has a positioning shoulder 11 and a fixing frame 12 for positioning the compression spring 7. The fixing frame 12 extends in the radial direction and is inserted into the opening of the frame 4. The fixed spring seat 5 reuses the opening of the frame 4 as a positioning structure to achieve relative fixation with the frame 4.

[0035] The top of the free spring seat 6 is provided with a positioning shoulder 11 for positioning the compression spring 7, and the bottom of the free spring seat 6 is provided with an arcuate groove 13 for positioning the valve ball 9. The arcuate groove 13 of the free spring seat 6 plays a guiding role in positioning the valve ball 9, thereby preventing the valve ball 9 from separating from the free spring seat 6.

[0036] In some embodiments, both the fixed spring seat 5 and the free spring seat 6 have through holes for passing oil. The arc-shaped groove 13 of the free spring seat 6 is in a spherical crown shape and the center of the sphere coincides with the axis of the through hole.

[0037] The oil hole 8 of the lower end cover 3 is provided with an internal thread 14 away from the hole of the upper end cover 2. The internal thread 14 of the oil hole 8 is used for disassembly of the filter element. The side wall of the upper end cover 2 is provided with a mounting ring groove 16, and a sealing ring 17 is provided in the mounting ring groove 16. The structure improves the sealing between the upper end cover 2 and other components. Through the structure, the filter element is connected to other components of the hydraulic brake control unit.

[0038] An annular mounting groove 15 is provided on the upper end cover 2 and the lower end cover 3, and the filter screen 1 and the frame 4 are inserted into the mounting groove 15. The embodiment provides positioning for the filter screen 1 and is also conducive to simplifying assembly. The side wall of the filter screen 1 fits with the outer side wall of the mounting groove 15. The inner side wall of the frame 4 fits with the inner side wall of the mounting groove. In some embodiments, the groove width of the mounting groove 15 is adapted to the width of the filter screen 1 and the thickness of the frame 4, so that the outer wall surface of the filter screen 1 fits with the mounting groove 15. The upper end cover 2 and the lower end cover 3 are fixedly connected to the filter screen 1 by bonding.

[0039] The filter element of the present application takes into account both compactness and reliability. Compactness means that the overall volume of the device only has the necessary upper end cover 2 and lower end cover 3 in the length direction compared with the filter screen 1 that plays a functional role, and the remaining components are all built into the filter screen 1. Reliability means that the present application adopts the line-surface matching method of the inner hole step and the valve ball 9, which can fully ensure the sealing of the valve ball to the oil hole 8 corresponding to the lower end cover 3. When the oil pressure inside the filter screen 1 is normal, the valve ball cannot be pushed open so that the two ends of the filter element (the oil hole 8 of the lower end cover 3 and the oil hole 8 of the upper end cover 2) can achieve passage. Specifically, the skeleton 4 plays the role of supporting the filter screen 1 as a rigid structure; the elastic member fixedly connected to the skeleton 4 at one end exerts an elastic force on the valve ball 9 in the bypass valve structure, so that it is pressed on the inner hole shoulder 10 of the oil hole 8 of the lower end cover 3. The diameter of the valve ball 9 is larger than the inner diameter of the inner hole shoulder 10, so as to achieve line-surface sealing. One side of the valve ball will be subject to the pressure generated by the oil pressure at the oil hole 8 of the lower end cover 3, and the other side will be subject to the sum of the oil pressure inside the filter 1 and the elastic force generated by the elastic member. When the filter 1 works normally, the latter will be greater than the former, thereby pressing the valve ball on the inner hole shoulder 10 to achieve sealing. However, when the filter 1 is blocked and fails, the internal oil pressure drops to a preset level, making the sum of the latter force less than the former, then the seal will fail, and the pressure oil connected to the lower end cover 3 will enter the inside of the filter 1, ensuring the normal operation of the hydraulic brake control unit. The movement of the oil in the auxiliary oil tank transmits signals to the whole machine control system through the sensor, notifying the machine section for maintenance.

[0040] The above-described embodiments are only preferred solutions of the present invention and are not intended to limit the present invention in any form. Other variations and modifications are possible without exceeding the technical solutions described in the claims.

Claims

1. A filter element with a bypass valve, characterized in that: It includes a hollow filter screen, an upper end cover and a lower end cover fixedly connected to both ends of the filter screen, an elastic member arranged in the filter screen, a bypass valve structure and a frame, the elastic member includes a fixed spring seat, a compression spring and a free spring seat, the upper end cover and the lower end cover are provided with oil holes, the bypass valve structure includes an inner hole shoulder arranged at the opening of the oil hole of the lower end cover and a valve ball between the inner hole shoulder and the free spring seat, the valve ball is separated from the inner hole shoulder when the medium pressure at the oil hole of the lower end cover is greater than the sum of the medium pressure inside the filter screen and the pre-pressure of the elastic member on the valve ball, so that the oil hole of the lower end cover and the oil hole of the upper end cover are in a connected state.

2. A filter element with a bypass valve according to claim 1, characterized in that: The frame is a cylinder with two open ends and a plurality of openings on the surface, and the two ends of the frame are respectively abutted between the upper end cover and the lower end cover.

3. A filter element with a bypass valve according to claim 2, characterized in that: The fixed spring seat has a positioning shoulder and a fixing frame for positioning the compression spring. The fixing frame extends in a radial direction and is inserted into the opening of the frame.

4. A filter element with a bypass valve according to claim 1 or 3, characterized in that: The top of the free spring seat is provided with a positioning shoulder for positioning the compression spring, and the bottom of the free spring seat is provided with an arc-shaped groove for positioning the valve ball.

5. The filter element with a bypass valve according to claim 1, characterized in that: The production process of the filter screen is the sintered felt process.

6. The filter element with a bypass valve according to claim 1, characterized in that: The oil hole of the lower end cover is provided with an internal thread at a hole away from the upper end cover.

7. The filter element with a bypass valve according to claim 1, characterized in that: The upper end cover and the lower end cover are provided with an annular mounting groove, and the filter screen and the frame are inserted into the mounting groove.

8. The filter element with a bypass valve according to claim 7, characterized in that: The side wall of the filter screen is fitted with the outer side wall of the installation groove.

9. A filter element with a bypass valve according to claim 7 or 8, characterized in that: The upper end cover and the lower end cover are fixedly connected to the filter screen by bonding.

10. The filter element with a bypass valve according to claim 6, characterized in that: The side wall of the upper end cover is provided with a mounting ring groove, and a sealing ring is arranged in the mounting ring groove.

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