Buffer type overflow valve
By simplifying the structure of the buffer relief valve and adopting a combined design of valve sleeve, main valve core and spool valve core, the processing cost and difficulty caused by the large number of parts in the existing technology are solved, and the smooth operation and extended service life of the hydraulic motor are achieved.
Patent Information
- Application Number
- CN202422861293.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-11-22
- Publication Date
- 2025-11-07
- Estimated Expiration
- 2034-11-22
AI Technical Summary
Existing buffer overflow valves have complex structures and numerous components, which increases processing costs and difficulty.
The structure of the buffer relief valve has been simplified, reducing the number of parts. It adopts a combination design of valve sleeve, main valve core, slide valve core and bushing, and achieves the buffer function through the connection of throttling channel and oil chamber.
It plays a role in buffering pressure fluctuations in hydraulic motors, ensuring the stability of system pressure, extending the service life of hydraulic motors, and reducing processing costs and difficulties.
Smart Images
Figure CN223524164U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model relates to valve technical field especially relates to a buffer overflow valve. BACKGROUND
[0002] The buffer overflow valve is widely used in the hydraulic motor. The buffer overflow valve mainly plays the role of constant pressure overflow in the hydraulic motor, and can buffer the suddenly increased hydraulic pressure in the hydraulic equipment to prevent the hydraulic equipment from being damaged due to the sudden pressure change in the operation process.
[0003] The buffer overflow valve in the prior art has a complex structure, mainly includes a valve sleeve, a main valve core, two valve seats and a pressure regulating spring, the two valve seats are respectively installed in the two ends of the valve sleeve, the two valve seats are respectively a first valve seat and a second valve seat, one end of the first valve seat is plugged with a plug, an oil inlet is formed in the second valve seat, an oil return port is formed in the valve sleeve, the main valve core is slidably arranged in the valve sleeve to control the communication state of the oil inlet and the oil return port, a slide valve core is also slidably arranged in the valve sleeve, and a piston is fixedly arranged in the valve sleeve, one end of the slide valve core is sleeved with one end of the main valve core, the other end of the slide valve core can abut against the end face of the plug, the piston is sleeved with the slide valve core and abuts against the end face of the plug, one end of the pressure regulating spring abuts against the main valve core, and the other end abuts against the first valve seat. The buffer overflow valve has a complex structure, and has many parts, which increases the processing cost and the processing difficulty.
[0004] Therefore, it is urgent to provide a buffer overflow valve to solve the above problems. CONTENT OF THE UTILITY MODEL
[0005] The utility model aims at providing a buffer overflow valve, which simplifies the structure, reduces the processing cost and the processing difficulty.
[0006] To achieve the purpose, the utility model adopts the following technical scheme:
[0007] The buffer overflow valve comprises a valve sleeve and a main valve core, one end of the valve sleeve is provided with a valve seat, the other end is provided with a plug, an oil inlet P is formed in the valve seat, an oil return port T is formed in the valve sleeve, the main valve core is slidably arranged in the valve sleeve, a slide valve core is slidably arranged in the plug, and a bushing is fixedly arranged in the plug, one end of the slide valve core penetrates the bushing and is sleeved with one end of the main valve core, a pressure regulating spring is sleeved with the main valve core, one end of the pressure regulating spring abuts against the main valve core, and the other end abuts against the slide valve core, a first oil cavity is formed between the slide valve core and the main valve core, a third oil cavity is formed between the slide valve core and the plug, a second oil cavity is formed between the bushing and the slide valve core, the first oil cavity is communicated with the oil inlet P through a throttling channel on the main valve core, and is communicated with the second oil cavity and the third oil cavity through corresponding oil holes on the slide valve core.
[0008] As an optional solution, the spool valve core comprises a coaxially connected head and a barrel part, the outer diameter of the head is larger than the outer diameter of the barrel part, the outer side wall of the head is in sealing sliding fit with the inner side wall of the plug, the barrel part is sleeved on one end of the main valve core, and the bushing is sleeved outside the barrel part and can be limited by abutting against the head.
[0009] As an optional solution, the oil hole on the spool valve core comprises a second throttling hole and a second oil passing hole, the second throttling hole is radially arranged on the side wall of the barrel part, the first oil cavity is communicated with the second oil cavity through the second throttling hole, and the second oil passing hole is axially arranged on the head, and the first oil cavity is communicated with the third oil cavity through the second oil passing hole.
[0010] As an optional solution, the valve sleeve is internally provided with a sealing cavity for accommodating the pressure regulating spring, the sealing cavity is communicated with the second oil cavity, and a drain port B is arranged on the side wall of the valve sleeve and communicated with the sealing cavity.
[0011] As an optional solution, the throttling channel on the main valve core comprises a guide port, a first throttling hole and a first oil passing hole which are communicated in sequence in the axial direction, the guide port is communicated with the oil inlet port P, the first oil passing hole is communicated with the first oil cavity, and the first throttling hole has a smaller hole diameter than the hole diameters of the guide port and the first oil passing hole.
[0012] As an optional solution, the outer side wall of the bushing is provided with external threads, the inner side wall of the plug is provided with internal threads, and the bushing is threadedly connected with the plug through the external threads and the internal threads.
[0013] As an optional solution, a one-letter slot is arranged on the end face of the one end of the bushing towards the valve seat.
[0014] As an optional solution, the outer side wall of the plug is provided with external threads, the inner side wall of the valve sleeve is provided with internal threads, and the plug is threadedly connected with the valve sleeve through the external threads and the internal threads.
[0015] As an optional solution, the main valve core comprises a valve rod and a valve head connected to one end of the valve rod, one end of the valve rod is arranged in the spool valve core, the outer peripheral surface of the valve head is in sealing sliding fit with the inner peripheral surface of the valve sleeve, and a conical sealing head is arranged on the end of the valve head away from the valve rod, and the conical sealing head is used for closing the oil inlet port P.
[0016] As an optional scheme, a limiting step is formed between the valve stem and the valve head, the spool is abutted against a spring seat at one end close to the pressure regulating spring, the spring seat is sleeved outside the main spool, one end of the pressure regulating spring is abutted against the limiting step, and the other end of the pressure regulating spring is abutted against the spring seat.
[0017] The utility model discloses beneficial effect has:
[0018] The utility model provides a buffer type overflow valve, apply to hydraulic motor, can play the buffer function when the system pressure instantaneous produces fluctuation, guarantee the stability of system pressure, make host computer reach the purpose of starting stable, parking stable, and in the invisible, guarantee the hydraulic motor operating stability, prolong the service life of hydraulic motor. BRIEF DESCRIPTION OF DRAWINGS
[0019] Figure 1 It is the structural schematic diagram of buffer type overflow valve provided in the prior art,
[0020] Figure 2 It is the structural schematic diagram of buffer type overflow valve provided by the utility model,
[0021] Figure 3 It is the right view of bushing provided by the utility model.
[0022] In the drawing,
[0023] 10, valve sleeve;20, main spool;21, throttling channel;30, first valve seat;40, second valve seat;50, spool;60, piston;70, pressure regulating spring;80, plug;90, lock nut;X10, first oil cavity;X20, second oil cavity;X30, third oil cavity;A, first via hole;B, second via hole;C, third via hole;
[0024] 1, valve sleeve;11, sealing cavity;2, main spool;2a, right side annular face;2b, left side annular face;21, valve stem;22, valve head;23, conical sealing head;24, limiting step;3, valve seat;4, plug;5, spool;5a, right side acting surface;5b, left side acting surface;51, head;52, barrel portion;6, bushing;61, slot;7, pressure regulating spring;8, spring seat;X1, first oil cavity;X2, second oil cavity;X3, third oil cavity;a, guide port;B, first throttling hole;C, first oil passing hole;D, second oil passing hole;E, second throttling hole. DETAILED DESCRIPTION
[0025] The utility model will be described in further detail below in combination with the drawings and embodiments. It can be understood that the specific embodiments described herein are merely used to explain the utility model and not to limit the utility model. In addition, it should be noted that only the parts related to the utility model are shown in the drawings for ease of description, not all the structures.
[0026] In the description of the utility model, unless otherwise explicitly specified and limited, the terms "connected", "connected", "fixed" should be understood broadly, for example, it can be fixedly connected, or it can be detachably connected, or it can be integrated; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium; it can be the internal communication of two elements or the interaction relationship of two elements. For ordinary skilled in the art, the specific meaning of the above terms in the utility model can be understood according to the specific circumstances.
[0027] In the utility model, unless otherwise explicitly specified and limited, the first feature "on" or "below" the second feature can include that the first and second features are in direct contact, or the first and second features are not in direct contact but are in contact through another feature between them. Moreover, the first feature "on", "above" and "on" the second feature includes that the first feature is directly above and obliquely above the second feature, or only indicates that the horizontal height of the first feature is higher than that of the second feature. The first feature "below", "below" and "below" the second feature includes that the first feature is directly below and obliquely below the second feature, or only indicates that the horizontal height of the first feature is less than that of the second feature.
[0028] In the description of the embodiment, the terms "up", "down", "right", etc. orientation or position relationship is based on the orientation or position relationship shown in the drawings, only for the convenience of description and simplification of operation, and does not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, therefore cannot be understood as a limitation on the utility model. In addition, the terms "first", "second" are only used to distinguish in description and have no special meaning.
[0029] The buffer overflow valve is widely used in hydraulic motors. The buffer overflow valve mainly plays the role of constant pressure overflow in the hydraulic motor, which can buffer the sudden rise of hydraulic pressure in the hydraulic equipment to prevent the hydraulic equipment from being damaged due to sudden pressure change during operation.
[0030] As Figure 1As shown, in the related art, the buffer type overflow valve mainly comprises a valve sleeve 10 and a main valve core 20. One end of the valve sleeve 10 is provided with a first valve seat 30, and the other end is provided with a second valve seat 40. One end of the first valve seat 30 is blocked by a plug 80. An oil inlet P is formed on the second valve seat 40. An oil return port T is formed on the valve sleeve 10. The main valve core 20 is slidably arranged in the valve sleeve 10 to control the communication state of the oil inlet P and the oil return port T. A spool valve core 50 is also slidably arranged in the valve sleeve 10, and a piston 60 is fixedly arranged. One end of the spool valve core 50 is sleeved on one end of the main valve core 20. The other end of the spool valve core 50 can abut against the end face of the plug 80. The piston 60 is sleeved outside the spool valve core 50 and abuts against the end face of the plug 80. A pressure regulating spring 70 is sleeved outside the main valve core 20. One end of the pressure regulating spring 70 abuts against the main valve core 20, and the other end abuts against the first valve seat 30. The first oil cavity X10 is formed between the spool valve core 50 and the main valve core 20. The second oil cavity X20 is formed between the spool valve core 50 and the first valve seat 30. The third oil cavity X30 is formed between the spool valve core 50 and the piston 60. The first oil cavity X10 is communicated with the oil inlet P through the throttling channel 21 on the main valve core 20, communicated with the second oil cavity X20 through the first through hole A on the spool valve core 50, and communicated with the third oil cavity X30 through the second through hole B and the third through hole C on the valve core.
[0031] The hydraulic oil of the system enters from the oil inlet P, and the pressure acts on the right side of the main valve core 20, and the oil enters the first oil cavity X10 through the throttling channel 21, and then the pressure acts on the left side of the main valve core 20, and due to the pressure difference, the force acting on the main valve core 20 is to the left and acts on the pressure regulating spring 707; the hydraulic oil in the first oil cavity X10 enters the second oil cavity X20 through the first through hole A on the spool core 50, and acts on the right side of the spool core 50, and the hydraulic oil in the first oil cavity X10 enters the third oil cavity X30 through the second through hole B and the third through hole C on the spool core 50, and acts on the left side of the spool core 50, and under static pressure, the force acting on the spool core 50 is to the right and acts on the pressure regulating spring 70. When the oil pressure at the oil inlet P suddenly increases, the force acting on the left side of the spool core 50 suddenly increases, pushing the spool core 50 to move right relative to the piston 60. In the process of moving right of the spool core 50, the third oil cavity X30 on the left side of the spool core 50 gradually becomes larger than the oil cavity (the sum of the first oil cavity X10 and the second oil cavity X20) on the right side. Due to the throttling effect of the throttling channel 21, the oil at the oil inlet P cannot quickly reach the third oil cavity X30, and the oil pressure in the third oil cavity X30 has not yet been established. At this time, the hydraulic pressure acting on the right side of the main valve core 20 overcomes the force of the pressure regulating spring 70 to make the main valve core 20 move to the left, open the contact between the main valve core 20 and the oil inlet P, and make the oil inlet P communicate with the oil return port T. The oil flows from the oil inlet P into the oil return port T for a short time, and the pressure is released. When the oil in the third oil cavity X30 gradually increases, it gradually pushes the spool core 50 to move right and compresses the pressure regulating spring 70, so that the compression amount of the pressure regulating spring 70 gradually increases, until the spool core 50 moves right to the first valve seat 30, and the pressure at the oil inlet P reaches the preset pressure. At this time, the main valve core 20 moves right under the action of the pressure regulating spring 70, until the oil inlet P is closed.
[0032] In the whole process, the function of constant pressure overflow is played, which can buffer the sudden increase of hydraulic pressure in the hydraulic equipment to prevent damage to the hydraulic equipment due to sudden pressure change during operation. However, from the structure, the structure of the buffer overflow valve is relatively complex, and there are many parts, which increases the processing cost and processing difficulty. Therefore, the embodiment provides a buffer overflow valve with a relatively simple structure, which is mainly applied to a hydraulic motor. The buffer overflow valve is used for overload protection of the hydraulic motor to prevent damage to the hydraulic motor due to sudden change of hydraulic pressure.
[0033] Specifically, as Figure 2As shown, the buffer overflow valve includes a valve sleeve 1 and a main valve core 2, one end of the valve sleeve 1 is provided with a valve seat 3, the other end is provided with a plug 4, the valve seat 3 is provided with an oil inlet P, the valve sleeve 1 is provided with an oil return port T, the main valve core 2 is slidably arranged in the valve sleeve 1 to control the communication state between the oil inlet P and the oil return port T, the plug 4 is provided with an installation cavity with an opening at one end in the axial direction, the installation cavity is slidably provided with a spool valve core 5 and fixedly provided with a bushing 6, the bushing 6 is a cylindrical sleeve structure, one end of the spool valve core 5 penetrates the bushing 6 and is sleeved on one end of the main valve core 2, the main valve core 2 is sleeved with a pressure regulating spring 7, one end of the pressure regulating spring 7 abuts against the main valve core 2, the other end abuts against the spool valve core 5, the spool valve core 5 and the main valve core 2 form a first oil cavity X1, the spool valve core 5 and the plug 4 form a third oil cavity X3, the bushing 6 and the spool valve core 5 form a second oil cavity X2, the first oil cavity X1 is communicated with the oil inlet P through the throttle channel on the main valve core 2, and is communicated with the second oil cavity X2 and the third oil cavity X3 through the corresponding oil holes on the spool valve core 5 respectively.
[0034] The hydraulic oil of the system enters from the oil inlet P, the pressure acts on the right annular surface 2a of the main valve core 2 (assuming the hydraulic pressure is F1), at the same time, the oil enters the first oil cavity X1 through the throttle channel of the main valve core 2, then the pressure acts on the left annular surface 2b of the main valve core 2 (assuming the hydraulic pressure is F2), at this time, due to the pressure difference, that is, F1>F2, the force of the main valve core 2 is to the left, and acts on the pressure regulating spring 7, the hydraulic pressure acting on the main valve core 2 is approximately equal to F1-F2; the hydraulic oil in the first oil cavity X1 enters the second oil cavity X2 through one of the oil holes on the spool valve core 5 and acts on the right side of the spool valve core 5. The surface 5a, at the same time, the hydraulic oil in the first oil cavity X1 enters the third oil cavity X3 through the other oil hole on the spool valve core 5, and acts on the left side of the spool valve core 5. The surface 5b, under static pressure, the force of the spool valve core 5 is to the right, and acts on the pressure regulating spring 7.
[0035] When the oil pressure at the oil inlet P suddenly increases, the force acting on the left side of the spool valve core 5 suddenly increases, pushing the spool valve core 5 to move to the right. In the process of moving to the right, the third oil chamber X3 on the left side of the spool valve core 5 gradually becomes larger than the oil chamber on the right side (the sum of the first oil chamber X1 and the second oil chamber X2). At the same time, hydraulic oil reaches the third oil chamber X3 on the left side of the spool valve core 5 from the throttling channel of the main valve core 2 and the oil hole on the spool valve core 5. Due to the throttling effect of the throttling channel of the main valve core 2, the oil at the oil inlet P cannot quickly reach the third oil chamber X3, and the third oil chamber X3 has not yet established oil pressure. At this time, the hydraulic pressure acting on the right annular surface 2a of the main valve core 2 overcomes the force of the pressure relief spring 7, causing the main valve core 2 to move to the left, opening the contact between the main valve core 2 and the oil inlet P, and connecting the oil inlet P with the oil return port T. The oil flows from the oil inlet P to the oil return port T for a short time, achieving pressure relief. When the oil in the third oil chamber X3 on the left side of the spool valve core 5 slowly increases, it gradually pushes the spool valve core 5 to move to the right and compresses the pressure relief spring 7, gradually increasing the compression amount of the pressure relief spring 7, until the spool valve core 5 moves to the right and abuts against the bushing 6, and the pressure at the oil inlet P reaches the preset pressure. At this time, the main valve core 2 moves to the right under the action of the pressure relief spring 7, until the oil inlet P is closed.
[0036] The whole process is very short, and its main function is to absorb the pressure pulse of the oil inlet P. When the system pressure fluctuates instantaneously, it can play a buffering function, ensure the stability of the system pressure, and ensure the smooth start and stop of the main machine. In addition, it ensures the smooth operation of the hydraulic motor and prolongs the service life of the hydraulic motor. In terms of structure, compared with the prior art, the buffer overflow valve reduces the use of parts, only needs a valve seat 3, and does not need to use a complex piston 60, only needs a simple structure bushing 6, simplifies the structure, and reduces the processing cost and difficulty.
[0037] Optionally, the outer side wall of the plug 4 is provided with external threads, the inner side wall of the valve sleeve 1 is provided with internal threads, the plug 4 is threadedly connected with the valve sleeve 1 through the external threads and the internal threads, and a sealing rubber ring is sleeved on the plug 4. Through the threaded connection, the connection reliability and sealing performance between the plug 4 and the valve sleeve 1 are ensured, and the plug 4 is convenient and fast to disassemble and assemble.
[0038] Further, in the embodiment, the outer side wall of the bushing 6 is provided with external threads, the inner side wall of the plug 4 is provided with internal threads, and the bushing 6 is threadedly connected with the plug 4 through the external threads and the internal threads. Through the threaded connection, the connection reliability and sealing performance between the bushing 6 and the valve sleeve 1 are ensured, and the bushing 6 is convenient and fast to disassemble and assemble.
[0039] Further, as shown in FIG. 6, the outer side wall of the bushing 6 is provided with external threads, the inner side wall of the plug 4 is provided with internal threads, and the bushing 6 is threadedly connected with the plug 4 through the external threads and the internal threads. Figure 3As shown in the figure, the bushing 6 is provided with a T-shaped slot 61 on the end face of the one end thereof facing the valve seat 3. By providing the T-shaped slot 61, the installation of the bushing 6 can be facilitated. During installation, the spool 5 is first installed in the plug 4, then the bushing 6 is sleeved on the spool 5 and installed in the plug 4, and then a screwing tool is inserted into the T-shaped slot 61 and the bushing 6 is screwed, so that the bushing 6 is screwed into the plug 4, which is convenient and fast.
[0040] Specifically, as Figure 2 shown, the spool 5 includes a head portion 51 and a barrel portion 52 coaxially connected, the outer diameter of the head portion 51 is larger than that of the barrel portion 52, the outer side wall of the head portion 51 is in sealing sliding fit with the inner side wall of the plug 4, an oil cavity X3 is formed between the head portion 51 and the plug 4, the barrel portion 52 is sleeved on one end of the main spool 2, the bushing 6 is sleeved on the barrel portion 52 and can abut against and be limited by the head portion 51, and a second oil cavity X2 is formed between the head portion 51 and the bushing 6. The spool 5 provided in the embodiment has a T-shaped step structure, which is simple in structure and convenient for processing and manufacturing.
[0041] Specifically, as Figure 2 shown, the oil hole on the spool 5 includes a second throttling hole e and a second oil passing hole d, the second throttling hole e is radially formed on the side wall of the barrel portion 52, the first oil cavity X1 is communicated with the second oil cavity X2 through the second throttling hole e, and the second oil passing hole d is axially formed on the head portion 51, the first oil cavity X1 is communicated with the third oil cavity X3 through the second oil passing hole d. The hydraulic oil in the first oil cavity X1 can flow into the second oil cavity X2 through the second throttling hole e, and can also flow into the third oil cavity X3 through the second oil passing hole d.
[0042] Further, as Figure 2 shown, the throttling passage on the main spool 2 includes a guide port a, a first throttling hole b and a first oil passing hole c communicated in sequence in the axial direction, the guide port a is communicated with the oil inlet P, the first oil passing hole c is communicated with the first oil cavity X1, and the first throttling hole b has a smaller hole diameter than the guide port a and the first oil passing hole c. After the hydraulic oil of the system enters from the oil inlet P, it flows into the first oil cavity X1 through the guide port a, the first throttling hole b and the first oil passing hole c in sequence, and the first throttling hole b has a smaller hole diameter, which plays a role of delayed damping.
[0043] As Figure 2As shown, the main valve core 2 comprises a valve stem 21 and a valve head 22 coaxially connected to one end of the valve stem 21, the outer diameter of the valve head 22 is larger than that of the valve stem 21, one end of the valve stem 21 is arranged in the spool valve core 5, the outer circumferential surface of the valve head 22 is in sealing sliding cooperation with the inner circumferential surface of the valve sleeve 1 to avoid the hydraulic oil entering the cavity where the pressure relief spring 7 is located through the gap between them as much as possible, and the end of the valve head 22 away from the valve stem 21 is provided with a tapered sealing head 23 for closing the oil inlet port P. The sealing surface of the tapered sealing head 23 is in contact with the port of the oil inlet port P to form a seal, and the sealing surface is a line contact seal formed by an annular line and a tapered surface, which has good sealing effect.
[0044] Further, as shown in Figure 2 , a limiting step 24 is formed between the valve stem 21 and the valve head 22, and the end of the spool valve core 5 close to the pressure relief spring 7 abuts against a spring seat 8, the spring seat 8 is arranged outside the main valve core 2, one end of the pressure relief spring 7 abuts against the limiting step 24, and the other end of the pressure relief spring 7 abuts against the spring seat 8. When the main valve core 2 moves to the left, the main valve core 2 compresses the pressure relief spring 7 to the left through the limiting step 24, and when the spool valve core 5 moves to the right, the spool valve core 5 compresses the pressure relief spring 7 to the right through the spring seat 8.
[0045] As shown in Figure 2 , the valve sleeve 1 is provided with a sealing cavity 11 for accommodating the pressure relief spring 7, the sealing cavity 11 is in communication with the second oil cavity X2, and the sidewall of the valve sleeve 1 is provided with a drain port B in communication with the sealing cavity 11. The hydraulic oil in the second oil cavity X2 can leak into the sealing cavity 11 through the groove on the outer circumferential wall of the cylinder portion 52, and the main function of the drain port B is to discharge the hydraulic oil leaked into the sealing cavity 11 to ensure the reliability of the overflow valve operation.
[0046] In combination Figure 2 , the working principle of the buffer type overflow valve provided by the embodiment is as follows:
[0047] The hydraulic oil of the system enters from the oil inlet port P, and the pressure acts on the right annular surface 2a of the main valve core 2 (assuming that the hydraulic pressure is F1), at the same time, the hydraulic oil flows into the first oil cavity X1 through the guide port a, the throttle hole b and the oil passage c in sequence, and the pressure acts on the left annular surface 2b of the main valve core 2 (assuming that the hydraulic pressure is F2), at this time, due to the pressure difference, that is, F1>F2, the force acting on the main valve core 2 is to the left, and the pressure relief spring 7 is acted on, the hydraulic pressure acting on the main valve core 2 is approximately equal to F1-F2; the hydraulic oil in the first oil cavity X1 flows into the second oil cavity X2 through the second throttle hole e, and acts on the right acting surface 5a of the spool valve core 5, at the same time, the hydraulic oil in the first oil cavity X1 flows into the third oil cavity X3 through the second oil passage d, and acts on the left acting surface 5b of the spool valve core 5, under static pressure, the force acting on the spool valve core 5 is to the right, and acts on the pressure relief spring 7.
[0048] When the oil pressure at the oil inlet P suddenly increases, the force acting on the left side of the slide valve core 5 suddenly increases, pushing the slide valve core 5 to move to the right. In the process of moving to the right, the third oil chamber X3 on the left side of the slide valve core 5 is gradually larger than the oil chamber (the sum of the first oil chamber X1 and the second oil chamber X2) on the right side. At the same time, hydraulic oil reaches the third oil chamber X3 on the left side of the slide valve core 5 from the guide port a, the first throttling hole b and the first oil passage c of the main valve core 2 and the second oil passage d on the slide valve core 5. Due to the throttling effect of the first throttling hole b of the main valve core 2, the oil at the oil inlet P cannot quickly reach the third oil chamber X3, and the third oil chamber X3 has not yet established the oil pressure. At this time, the hydraulic pressure acting on the right side of the main valve core 2 overcomes the force of the pressure relief spring 7, so that the main valve core 2 moves to the left, opens the contact between the main valve core 2 and the oil inlet P, and makes the oil inlet P communicate with the oil return port T. The oil flows from the oil inlet P to the oil return port T for a short time, and the high-pressure oil is depressurized. When the oil in the third oil chamber X3 on the left side of the slide valve core 5 slowly increases, the third oil chamber X3 gradually pushes the slide valve core 5 to move to the right and compresses the pressure relief spring 7, so that the compression amount of the pressure relief spring 7 increases. Until the slide valve core 5 moves to the right and abuts against the bushing 6, the pressure at the oil inlet P reaches the preset pressure. At this time, the main valve core 2 moves to the right under the action of the pressure relief spring 7, until the oil inlet P is closed.
[0049] In this process, the pressure pulse of the oil inlet P is absorbed, and when the system pressure fluctuates instantaneously, the buffering function can be played, the system pressure is ensured to be stable, the main machine is started and stopped smoothly, and the hydraulic motor is operated smoothly, thereby prolonging the service life of the hydraulic motor.
[0050] Obviously, the above embodiments of the utility model are only examples for clearly illustrating the utility model, and are not a limitation on the embodiments of the utility model. For ordinary skilled in the art, various obvious changes, re-adjustment and replacement can be made without departing from the protection scope of the utility model. Here, it is not necessary and impossible to enumerate all the embodiments. Any modification, equivalent replacement and improvement made within the spirit and principle of the utility model should be included in the protection scope of the utility model claims.
Claims
1. A cushioned spill valve characterized in that, The valve sleeve (1) is provided with a valve seat (3) at one end and a plug (4) at the other end, the valve seat (3) is provided with an oil inlet P, the valve sleeve (1) is provided with an oil return port T, the main valve core (2) is slidably arranged in the valve sleeve (1), the plug (4) is slidably provided with a slide valve core (5) and fixedly provided with a bushing (6), one end of the slide valve core (5) penetrates the bushing (6) and is sleeved on one end of the main valve core (2), the main valve core (2) is sleeved with a pressure regulating spring (7), one end of the pressure regulating spring (7) abuts against the main valve core (2), the other end abuts against the slide valve core (5), the slide valve core (5) and the main valve core (2) form a first oil cavity (X1), and the slide valve core (5) and the plug (4) form a third oil cavity (X3), the bushing (6) and the slide valve core (5) form a second oil cavity (X2), the first oil cavity (X1) is communicated with the oil inlet P through a throttling channel on the main valve core (2), and is communicated with the second oil cavity (X2) and the third oil cavity (X3) through corresponding oil holes on the slide valve core (5) respectively.
2. The cushioned spill valve of claim 1, wherein, The slide valve core (5) comprises a head portion (51) and a barrel portion (52) connected coaxially, the outer diameter of the head portion (51) is greater than that of the barrel portion (52), the outer side wall of the head portion (51) is in sealing sliding fit with the inner side wall of the plug (4), the barrel portion (52) is sleeved on one end of the main valve core (2), and the bushing (6) is sleeved on the outer side wall of the barrel portion (52) and can abut against the head portion (51) to limit.
3. The cushioned spill valve of claim 2, wherein, The oil hole on the slide valve core (5) comprises a second throttling hole (e) and a second oil passing hole (d), the second throttling hole (e) is radially formed on the side wall of the barrel portion (52), the first oil cavity (X1) is communicated with the second oil cavity (X2) through the second throttling hole (e), and the second oil passing hole (d) is axially formed on the head portion (51), the first oil cavity (X1) is communicated with the third oil cavity (X3) through the second oil passing hole (d).
4. The cushioned spill valve of claim 3, wherein, The valve sleeve (1) is provided with a sealing cavity (11) for accommodating the pressure regulating spring (7), the sealing cavity (11) is communicated with the second oil cavity (X2), and the valve sleeve (1) is provided with a drain port B on the side wall, the drain port B is communicated with the sealing cavity (11).
5. The cushioned spill valve of claim 1, wherein, The throttling channel on the main valve core (2) comprises a guide port (a), a first throttling hole (b) and a first oil passing hole (c) communicated in sequence in the axial direction, the guide port (a) is communicated with the oil inlet P, the first oil passing hole (c) is communicated with the first oil cavity (X1), and the diameter of the first throttling hole (b) is smaller than that of the guide port (a) and the first oil passing hole (c).
6. The cushioned spill valve of claim 1, wherein, The outer side wall of the bushing (6) is provided with external threads, the inner side wall of the plug (4) is provided with internal threads, and the bushing (6) is threadedly connected with the plug (4) through the external threads.
7. The cushioned spill valve of claim 6, wherein, A T-shaped slot (61) is formed on the end face of the bushing (6) facing the valve seat (3).
8. The cushioned spill valve of claim 1, wherein, The outer side wall of the plug (4) is provided with external threads, the inner side wall of the valve sleeve (1) is provided with internal threads, and the plug (4) is threadedly connected to the valve sleeve (1) through the external threads and the internal threads.
9. The cushioned spill valve of claim 1, wherein, The main valve core (2) comprises a valve rod (21) and a valve head (22) connected to one end of the valve rod (21), one end of the valve rod (21) is arranged in the spool valve core (5), the outer circumferential surface of the valve head (22) is in sealing sliding cooperation with the inner circumferential surface of the valve sleeve (1), and the end of the valve head (22) away from the valve rod (21) is provided with a conical sealing head (23) for closing the oil inlet port P.
10. The cushioned spill valve of claim 9, wherein, A limiting step (24) is formed between the valve rod (21) and the valve head (22), one end of the spool valve core (5) close to the pressure regulating spring (7) abuts against a spring seat (8), the spring seat (8) is sleeved on the outer side of the main valve core (2), one end of the pressure regulating spring (7) abuts against the limiting step (24), and the other end of the pressure regulating spring (7) abuts against the spring seat (8).