Overflow valve

Abstract

The utility model relates to the technical field of hydraulic pressure, in particular to an overflow valve. An overflow valve comprises a valve body, an oil inlet, an oil outlet, a valve core, a valve core, a valve core and a valve core, wherein the valve body is provided with an oil inlet and an oil outlet; the valve element is assembled on the valve body in a sliding mode, and an inner cavity is formed in the valve element; the valve element abuts against the valve body under the action of the first elastic piece, and communication between the oil inlet and the oil outlet is blocked. A channel communicated with the oil outlet and the inner cavity is formed in the valve core; a one-way valve is formed on the valve element, and fluid in the inner cavity can flow to the cavity where the first elastic piece is located through the one-way valve in a one-way mode. The overflow valve solves the technical problem that in the prior art, when an overflow valve is in a non-pressurization state, a piston can be affected by the pressure of an oil outlet, and then the pressure of pressure oil fluctuates.

Description

Technical Field

[0001] The utility model relates to the technical field of hydraulics, and particularly relates to a relief valve. Background Art

[0002] A relief valve is a pressure control valve, which mainly plays safety protection roles such as constant pressure overflow, voltage stabilization, and system unloading in hydraulic equipment. In the hydraulic system of construction machinery, the relief valve is crucial for system pressure limitation and safety protection. At present, a fixed pressure is set when engineering machinery equipment leaves the factory, which can meet the use requirements of general working conditions.

[0003] In the prior art, in order to improve the applicability of the relief valve, the relief valve often has an adjustment structure. For example, the document with the application number CN202121055854.1 discloses an adjustable relief valve, which includes a valve body and a valve core. An oil inlet and an oil outlet are formed on the valve body, and the valve core is slidably assembled in the valve body. In the initial state, under the action of an elastic member, the valve core abuts against the inner wall of the valve body, blocking the oil inlet and the oil outlet; when the acting force of the pressure oil entering the oil inlet on the valve core is greater than the acting force of the elastic member on the valve core, the valve core slides along the valve body, and the oil inlet and the oil outlet are communicated, and the pressure oil entering from the oil inlet exits through the oil outlet. A pressure regulating member is assembled at the open end of the valve body. The pressure regulating member is slidably assembled on the valve body, one end of the pressure regulating member extends into the valve cavity of the valve body, the other end of the pressure regulating member is located outside the valve body, a control cavity is formed between the inner end of the pressure regulating member and the valve core, and a control oil port is also opened on the outer end of the pressure regulating member, and the control oil port is communicated with the control cavity. Specifically, an external thread is formed on the outer surface of the middle part of the pressure regulating member, an internal thread is formed at the opening of the valve body, and the pressure regulating member is threadedly connected with the valve body; a cavity with two open ends is formed inside the pressure regulating member, a partition extends from the inner wall of the pressure regulating member, and the partition divides the inner cavity of the pressure regulating member into a control cavity and a control oil port. One end of the piston of the valve core away from the core head extends into the control cavity and is slidably matched with the pressure regulating member. The control oil port is connected with control oil, and an oil hole is formed on the partition to communicate the control oil port and the control cavity.

[0004] The above-mentioned relief valve can achieve adjustable pressure, but in the non-boost state, the piston will be affected by the pressure of the oil outlet, resulting in pressure fluctuations of the pressure oil. Summary of the Utility Model

[0005] In order to solve the technical problem that in the prior art, in the non-boost state, the piston of the relief valve is affected by the pressure of the oil outlet, resulting in pressure fluctuations of the pressure oil, the utility model provides a relief valve, which solves the above technical problem.

[0006] In order to solve the above technical problem, the utility model provides a relief valve, including:

[0007] A valve body, on which an oil inlet and an oil outlet are formed;

[0008] A spool valve core, which is slidably assembled on the valve body, and an inner cavity is formed in the spool valve core;

[0009] A first elastic member, under the action of the first elastic member, the spool valve core is closely abutted against the valve body to block the communication between the oil inlet and the oil outlet;

[0010] A channel communicating the oil outlet and the inner cavity is formed on the spool valve core; a check valve is formed on the spool valve core, and the fluid in the inner cavity can flow unidirectionally through the check valve to the cavity where the first elastic member is located.

[0011] According to an embodiment of the present invention, the spool valve core includes a spool valve core body and a piston that are slidably matched. The end of the spool valve core body is inserted into the piston, and the inner cavity is formed between the spool valve core and the piston.

[0012] According to an embodiment of the present invention, under the action of the first elastic member, a seal is formed between the outer peripheral surface of the spool valve core body and the inner surface of the valve body.

[0013] According to an embodiment of the present invention, an insertion portion is formed at the end of the spool valve core body, a limiting surface is formed on the spool valve core body near the insertion portion, and the piston can abut against the limiting surface to limit the relative position between the spool valve core body and the piston.

[0014] According to an embodiment of the present invention, the channel is arranged on the circumferential wall of the piston, and the check valve is arranged on the bottom surface of the piston.

[0015] According to an embodiment of the present invention, a flow-through hole with a changing inner diameter is formed on the bottom surface of the piston. The check valve includes a valve ball and a second elastic member. The valve ball is assembled in the flow-through hole, and the second elastic member acts on the valve ball.

[0016] According to an embodiment of the present invention, it further includes an adjusting member, which is adjustably assembled on the valve body. A cavity is formed between the adjusting member and the spool valve core, and both ends of the first elastic member act on the adjusting member and the spool valve core respectively.

[0017] According to an embodiment of the present invention, the adjusting member is threadedly assembled on the valve body and is locked by a locking member.

[0018] According to an embodiment of the present invention, a control oil port is arranged on the adjusting member, and control oil enters the cavity through the control oil port.

[0019] Based on the above technical solutions, the technical effects that the present invention can achieve are:

[0020] For the overflow valve of the present utility model, by providing a check valve on the valve core, when in a non-pressurized state, the oil fluid at the oil outlet enters the inner cavity through the channel and then can enter the cavity where the first elastic member is located through the check valve, so that the valve core is in a balanced state and will not be affected by the oil pressure at the oil outlet, thereby reducing pressure fluctuations.

[0021] For the overflow valve of the present utility model, the valve core is provided in a split manner and includes a valve core body and a piston that are slidably mated, which facilitates the assembly of the valve core. The sliding insertion between the valve core body and the piston facilitates the coaxial assembly between the two, and the limiting surface can limit the relative position between the two.

[0022] For the overflow valve of the present utility model, an adjusting member and a cavity are provided. The pressure regulation can be achieved by adjusting the position of the adjusting member on the valve body; the pressure regulation can also be achieved by introducing control oil into the cavity from the control oil port. The two pressure regulation methods can increase the pressure regulation range. When using control oil for pressure regulation, the control oil can enter the cavity. Due to the check valve, the control oil will not enter the inner cavity, and thus will not affect the operation of the overflow valve. Description of the Drawings

[0023] Figure 1 is the front view of the overflow valve of the present utility model;

[0024] Figure 2 is the left view of the overflow valve;

[0025] Figure 3 is the right view of the overflow valve;

[0026] Figure 4 is the sectional view of the overflow valve;

[0027] Figure 5 is the partial structural schematic diagram of the check valve assembled on the valve core;

[0028] In the figure: 1-valve body; 11-inlet oil port; 12-outlet oil port; 2-valve core; 21-valve core body; 22-piston; 221-inner cavity; 222-channel; 223-overflow hole; 3-first elastic member; 4-check valve; 41-valve ball; 42-second elastic member; 5-adjusting member; 51-cavity; 52-control oil port; 6-locking member. Detailed Description of the Invention

[0029] The following will clearly and completely describe the technical solutions in the embodiments of the present utility model in conjunction with the accompanying drawings in the embodiments of the present utility model. Obviously, the described embodiments are only a part of the embodiments of the present utility model, rather than all of the embodiments. The description of at least one exemplary embodiment below is actually only illustrative and in no way restricts the present utility model and its application or use. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present utility model without creative efforts belong to the scope protected by the present utility model.

[0030] 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 "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or their combinations.

[0031] Unless otherwise specifically stated, the relative arrangements, numerical expressions, and numerical values of the components and steps described in these embodiments do not limit the scope of the present utility model. At the same time, it should be understood that, for the sake of convenience of description, the sizes of the various parts shown in the drawings are not drawn in actual proportional relationships. Technologies, methods, and devices known to those of ordinary skill in the relevant fields may not be discussed in detail, but where appropriate, the said technologies, methods, and devices should be regarded as part of the specification. In all the examples shown and discussed here, any specific value should be construed as merely exemplary and not as a limitation. Therefore, other examples of the exemplary embodiments may have different values. It should be noted that: like reference numerals and letters denote like items in the following drawings, and thus, once an item is defined in one drawing, it does not need to be further discussed in subsequent drawings.

[0032] In the description of the present utility model, it should be understood that the orientation or positional relationships indicated by orientation words such as "front, rear, upper, lower, left, right", "lateral, vertical, perpendicular, horizontal", and "top, bottom" are generally based on the orientation or positional relationships shown in the drawings, and are only for the convenience of describing the present utility model and simplifying the description. Without contrary description, these orientation words do not indicate and imply that the device or element referred to must have a specific orientation or be constructed and operated in a specific orientation, and thus should not be construed as limiting the scope of protection of the present utility model; the orientation words "inside, outside" refer to the inside and outside relative to the contour of each component itself.

[0033] For ease of description, spatial relative terms such as "above", "over", "on the upper surface", "upper" etc. can be used here to describe the spatial positional relationship of a device or feature shown in the figure with other devices or features. It should be understood that the spatial relative terms are intended to encompass different orientations in use or operation in addition to the orientation depicted in the figure for the device. For example, if the device in the attached drawing is inverted, a device described as "above" or "over" other devices or structures will then be positioned "below" or "beneath" the other devices or structures. Thus, the exemplary term "above" can include both the orientations of "above" and "below". The device can also be positioned in other different ways (rotated 90 degrees or in other orientations), and corresponding interpretations should be made for the spatial relative descriptions used here.

[0034] In addition, it should be noted that using terms such as "first", "second" etc. to define components is only for the convenience of differentiating the corresponding components. Without additional statements, the above terms have no special meanings, and thus should not be construed as limiting the protection scope of the present utility model.

[0035] As Figures 1-5 shown, this embodiment provides a relief valve, which includes a valve body 1 and a valve core 2. An oil inlet 11 and an oil outlet 12 are provided on the valve body 1. In the initial state, the valve core 2 is pressed against the inner circumferential surface of the valve body 1 under the action of a first elastic member 3, blocking the communication between the oil inlet 11 and the oil outlet 12. When the acting force of the pressure oil at the oil inlet 11 on the valve core 2 is greater than the acting force of the first elastic member 3 on the valve core 2, the valve core 2 can be pushed to slide open, and the oil inlet 11 and the oil outlet 12 are communicated. The pressure oil entering from the oil inlet 11 can flow out through the oil outlet 12, avoiding excessive system pressure.

[0036] The valve body 1 has a hollow structure. An installation hole with one end open is formed inside the valve body 1. The oil inlet 11 and the oil outlet 12 are provided at one end of the valve body 1 far away from the opening. The oil inlet 11 can be provided as multiple ones, and the multiple oil inlets 11 are evenly distributed along the circumferential direction. The oil outlet 12 can also be provided as multiple ones, and the multiple oil outlets 12 are evenly distributed along the circumferential direction. Preferably, the oil inlet 11 can be provided as an inclined port, and a tapered wall is formed on the inner wall of the valve body 1 between the oil inlet 11 and the oil outlet 12. The valve core 2 can be pressed against the tapered wall under the action of the first elastic member 3 to form a seal, blocking the communication between the oil inlet 11 and the oil outlet 12.

[0037] The spool 2 is a split structure. The spool 2 includes a spool body 21 and a piston 22. The spool body 21 and the piston 22 are slidably assembled. The piston 22 has an open-ended structure at one end. An insertion portion is formed at the end of the spool body 21 and can be slidably inserted into the opening of the piston 22. A limiting surface is formed on the spool body 21 near the insertion portion, and the piston 22 can abut against the limiting surface to limit the relative position between the spool body 21 and the piston 22.

[0038] As a preferred technical solution of this embodiment, the piston 22 is located between the spool body 21 and the first elastic member 3. The spool body 21 is disposed near the oil inlet 11 and the oil outlet 12. Under the action of the first elastic member 3, the spool body 21 abuts against the inner wall of the valve body 1 to block the oil inlet 11 and the oil outlet 12.

[0039] As a preferred technical solution of this embodiment, an inner cavity 221 is formed between the spool body 21 and the piston 22. A channel 222 is formed on the circumferential wall of the spool body 21. The channel 222 communicates with the inner cavity 221. The oil outlet 12 can communicate with the channel 222 through the gap between the piston 22 and the valve body 1.

[0040] A check valve 4 is provided on the bottom surface of the piston 22. The oil in the inner cavity 221 can flow unidirectionally through the check valve 4 into the cavity 51 where the first elastic member 3 is located. In a non-pressurized state, the oil at the oil outlet 12 can enter the inner cavity 221 through the channel 222, and then enter the cavity 51 where the first elastic member 3 is located through the check valve 4. The hydraulic pressure acting on the piston 22 is in a balanced state and no pressure fluctuation will occur.

[0041] Specifically, a flow hole 223 is provided on the bottom surface of the piston 22. The flow hole 223 is a through hole with a variable inner diameter. The check valve 4 includes a valve ball 41 and a second elastic member 42. The valve ball 41 is installed in the flow hole 223, and the second elastic member 42 acts on the valve ball 41.

[0042] As a preferred technical solution of this embodiment, the second elastic member 42 can be a circlip.

[0043] To achieve pressure regulation, the relief valve of this embodiment further includes an adjusting member 5. The adjusting member 5 is assembled on the valve body 1 with an adjustable position. The two ends of the first elastic member 3 act on the piston 22 and the adjusting member 5 respectively, and the pressure regulation can be achieved by adjusting the position of the adjusting member 5 on the valve body 1.

[0044] As a preferred technical solution of this embodiment, the adjusting member 5 is a hollow structure. One end of the piston 22 away from the spool body 21 can extend into the adjusting member 5 and slide. A cavity 51 is formed between the piston 22 and the adjusting member 5, and the first elastic member 3 is accommodated in the cavity 51.

[0045] As a preferred technical solution of this embodiment, the adjusting member 5 can be threadedly assembled on the valve body 1. The opening of the valve body 1 is provided with internal threads, and external threads are distributed on the adjusting member 5, enabling threaded assembly. After the adjusting member 5 is screwed into the valve body 1, it can be locked by the locking member 6. The locking member 6 can be, but is not limited to, a lock nut.

[0046] As a preferred technical solution of this embodiment, in order to achieve diversity in pressure regulation, a control oil port 52 is formed at the outer end of the adjusting member 5 extending out of the valve body 1, through which control oil can be introduced. The control oil enters the cavity 51 through the control oil port 52 and acts on the piston 22, thereby achieving the pressure regulation function.

[0047] For the overflow valve of this embodiment, when there is no pressure increase, the force exerted by the oil pressure at the oil outlet 12 on the piston 22 is balanced, and thus no pressure fluctuation will be caused, enabling accurate overflow.

[0048] The above has described in detail the embodiments of the present invention in conjunction with the accompanying drawings. However, the present invention is not limited to the above embodiments. Within the scope of knowledge possessed by those of ordinary skill in the art, various changes can be made without departing from the purpose of the present invention.

Claims

1. An overflow valve, characterized in that, Comprising: A valve body (1) with an oil inlet (11) and an oil outlet (12) formed thereon; A valve core (2) slidably assembled on the valve body (1), and an inner cavity (221) is formed inside the valve core (2); A first elastic member (3), under the action of which the valve core (2) abuts against the valve body (1) to block the communication between the oil inlet (11) and the oil outlet (12); A channel (222) communicating the oil outlet (12) with the inner cavity (221) is formed on the valve core (2); a check valve (4) is formed on the valve core (2), and the fluid in the inner cavity (221) can flow unidirectionally through the check valve (4) to the cavity (51) where the first elastic member (3) is located.

2. The overflow valve according to claim 1, characterized in that, The valve core (2) includes a valve core body (21) and a piston (22) in sliding fit, the end of the valve core body (21) is inserted into the piston (22), and the inner cavity (221) is formed between the valve core (2) and the piston (22).

3. The overflow valve according to claim 2, wherein, Under the action of the first elastic member (3), the outer peripheral surface of the valve core body (21) forms a seal with the inner surface of the valve body (1).

4. An overflow valve according to claim 2, characterized in that, An insertion portion is formed at the end of the valve core body (21), a limiting surface is formed on the valve core body (2) near the insertion portion, and the piston (22) can abut against the limiting surface to limit the relative position between the valve core body (2) and the piston (22).

5. An overflow valve according to claim 2, characterized in that, The channel (222) is arranged on the circumferential wall of the piston (22), and the check valve (4) is arranged on the bottom surface of the piston (22).

6. An overflow valve according to claim 5, characterized in that, An over-flow hole (223) with a variable inner diameter is formed on the bottom surface of the piston (22), the check valve (4) includes a valve ball (41) and a second elastic member (42), the valve ball (41) is assembled in the over-flow hole (223), and the second elastic member (42) acts on the valve ball (41).

7. An overflow valve according to claim 1, characterized in that, It further includes an adjusting member (5) adjustably assembled on the valve body (1), a cavity (51) is formed between the adjusting member (5) and the valve core (2), and both ends of the first elastic member (3) act on the adjusting member (5) and the valve core (2) respectively.

8. An overflow valve according to claim 7, characterized in that, The adjusting member (5) is threadedly assembled on the valve body (1) and locked by a locking member (6).

9. An overflow valve according to claim 7, characterized in that, A control oil port (52) is arranged on the adjusting member (5), and control oil enters the cavity (51) through the control oil port (52).

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