A rotary buffer valve

Abstract

The present invention discloses a rotary buffer valve, belonging to the technical field of construction machinery. It includes: a valve body, which is provided with an A port, a B port, a P port and a T port, and both the P port and the T port are communicated with the A port or the B port. The valve body integrates multiple functions, including: a buffering function and an oil replenishing function, which includes a first dynamic buffer overflow valve, a second dynamic buffer overflow valve and a static buffer overflow valve. The A port, the first dynamic buffer overflow valve, the second dynamic buffer overflow valve and the B port are communicated, and the static buffer overflow valve is communicated with the A port and the P port; a commutation function, which includes a commutation valve, and the P port is communicated with the A port or the B port through the commutation valve; a free rotation function, which includes a first commutation solenoid valve and a second commutation solenoid valve. When both are opened and the P port, the a port and the b port are closed, the A port is communicated with the B port; a brake function, which includes a Y port, a P1 port and a hydraulic control commutation valve, and the P1 port can be communicated with the Y port through the hydraulic control commutation valve. The rotary buffer valve integrates five functions, which is more convenient for installation and use.

Description

Technical Field

[0001] The present invention belongs to the technical field of construction machinery, and particularly relates to a swing buffer valve. Background Art

[0002] Generally speaking, the moment of inertia of the swing mechanism of construction machinery is relatively large, and swing impact is likely to occur during startup and shutdown, seriously affecting the control performance of the swing operation.

[0003] The swing buffer valve is a hydraulic component used to control the swing action, and its main function is to reduce swing impact. However, the current swing buffer valve generally only has a buffering function. However, the swing mechanism of construction machinery also requires functions such as commutation, oil replenishment, brake, and free rotation during operation. However, at present, there is no swing buffer valve integrated with the above functions, but a split structure is used, which has problems of low integration and low space utilization rate. Summary of the Invention

[0004] The present invention aims at the above problems existing in the prior art and proposes a swing buffer valve that is convenient to integrate with functions such as buffering, commutation, braking, oil replenishment, and free rotation.

[0005] The present invention can be realized by the following technical solutions:

[0006] A swing buffer valve, comprising a valve body provided with an A port, a B port, a P port, and a T port. The A port and the B port are respectively used to connect to both ends of an external motor. The P port is communicated with the A port or the B port, and the T port is communicated with the A port or the B port. It is characterized in that the valve body is integrated with multiple functions, including:

[0007] Buffering function, which includes a first dynamic buffer relief valve, a second dynamic buffer relief valve, and a static buffer relief valve. The A port, the first dynamic buffer relief valve, the second dynamic buffer relief valve, and the B port are communicated. When the motor starts and generates a startup impact, pressure is released between the A port and the B port through the first dynamic buffer relief valve and the second dynamic buffer relief valve. One end of the static buffer relief valve is communicated with the A port and the other end is communicated with the P port. When the motor stops and generates a shutdown impact, the oil in the A port or the B port flows back to the T port through the static buffer relief valve.

[0008] Oil replenishment function. When the motor stops, pressure is released and oil is replenished between the A port and the B port through the first dynamic buffer relief valve and the second dynamic buffer relief valve, and at the same time, the T port replenishes oil to the A port or the B port.

[0009] A commutation function, which includes a commutation valve. The P port is communicated with the A port or the B port through the commutation valve. Two ends of the commutation valve are respectively an a port and a b port. Oil enters through the a port or the b port to control the communication between the P port and the A port or the B port.

[0010] A free rotation function, which includes a first commutation solenoid valve and a second commutation solenoid valve. When the first commutation solenoid valve and the second commutation solenoid valve are both opened and the P port, the a port and the b port are all closed, the A port and the B port are communicated with each other through the first commutation solenoid valve and the second commutation solenoid valve.

[0011] A brake function, which includes a Y port, a P1 port and a hydraulically controlled commutation valve. When oil enters through the a port or the b port, it pushes the hydraulically controlled commutation valve to move and makes the P1 port communicate with the Y port.

[0012] As a further improvement of the present invention, an oil inlet cavity, a first oil passage and a second oil passage are provided in the valve body. The P port is communicated with the oil inlet cavity. The oil inlet cavity is communicated with the commutation valve and the static buffer overflow valve. The A port is communicated with the first dynamic buffer overflow valve through the first oil passage. The B port is communicated with the second dynamic buffer overflow valve through the second oil passage. A connecting oil passage is provided between the first dynamic buffer overflow valve and the second dynamic buffer overflow valve.

[0013] As a further improvement of the present invention, the commutation valve includes a left control cylinder block and a right control cylinder block. One end of the left control cylinder block is connected to the valve body and the other end is connected with a left one-way throttle valve. The oil port of the left one-way throttle valve is the b port. The left one-way throttle valve is communicated with the inner cavity of the left control cylinder block. One end of the right control cylinder block is connected to the valve body and the other end is connected with a right one-way throttle valve. The oil port of the right one-way throttle valve is the a port. The right one-way throttle valve is communicated with the inner cavity of the right control cylinder block.

[0014] As a further improvement of the present invention, the left one-way throttle valve and the right one-way throttle valve have the same structure. A one-way damping valve is provided inside both of them. The a port and the b port are opened or closed by the movement of the one-way damping valve. A damping is also provided inside the one-way damping valve.

[0015] As a further improvement of the present invention, a commutation valve cavity is provided in the valve body. The commutation valve further includes a commutation valve sleeve. The commutation valve sleeve is movably arranged in the commutation valve cavity, and two ends of the commutation valve sleeve respectively extend into the left control cylinder block and the right control cylinder block.

[0016] As a further improvement of the present invention, cavities are provided at both ends of the reversing valve sleeve. A plug, a return spring, a check ball, a connecting through hole, and an oil passage chamber are arranged in the cavity. The plug is connected to the reversing valve sleeve. The two ends of the return spring are respectively abutted against the plug and the check ball. The oil passage chamber is communicated with the oil inlet chamber. The two connecting through holes are respectively communicated with the first oil passage and the second oil passage. The communication or disconnection between the oil passage chamber and the connecting through hole is achieved by the movement of the check ball.

[0017] As a further improvement of the present invention, a reversing valve rod, a guide sleeve, a reversing spring, and a reversing spring seat are arranged in the left control cylinder body. The reversing valve rod is inserted into the plug and the two are connected through the guide sleeve. The number of the reversing spring seats is two and they are respectively connected to the reversing valve rod and the plug. The two ends of the reversing spring are connected to the two reversing spring seats. The oil entering from port b pushes the reversing valve rod to move. The reversing valve rod pushes the reversing valve sleeve to move towards the direction of the right control cylinder body through the plug, so that the oil inlet chamber is communicated with the second oil passage.

[0018] As a further improvement of the present invention, the right control cylinder body is provided as a cavity. The oil entering from port a pushes the reversing valve sleeve to move towards the direction of the left control cylinder body through the plug, so that the oil inlet chamber is communicated with the first oil passage.

[0019] As a further improvement of the present invention, the valve body is further provided with a T port and an oil return passage. The oil return passage has three passage openings and is communicated with the T port. Among them, one passage opening is communicated with the oil inlet chamber, and the other two passage openings are respectively communicated with the reversing valve chamber. And the movement of the reversing valve sleeve makes the two passage openings be respectively communicated with the first oil passage and the second oil passage. In addition, two oil replenishing check valves are further arranged in the oil return passage. The oil return passage is directly communicated with port A and port B through the two oil replenishing check valves.

[0020] As a further improvement of the present invention, the valve body is further provided with an L port, and the L port is communicated with the second reversing solenoid valve and the hydraulic control reversing valve.

[0021] Compared with the prior art, the present invention has the following beneficial effects:

[0022] 1. The swing buffer valve of the present application integrates functions of buffering, oil replenishing, reversing, braking, and free rotation at the same time, with high integration degree. Only one swing buffer valve can provide various functions required by a crane, which is more conducive to production and installation. At the same time, the space utilization rate is improved during installation.

[0023] 2. When the motor starts, high pressure is generated at the oil inlet ports of Port A and Port B. At this time, the oil at the high-pressure port can flow into Port T through the first dynamic buffer overflow valve and the second dynamic buffer overflow valve for pressure relief, reducing the rotational impact during motor startup and preventing the cab from shaking.

[0024] 3. When the motor stops, one of Port A and Port B generates negative pressure and the other generates high pressure. At this time, the oil at the high-pressure port can flow into Port A through the first dynamic buffer overflow valve and the second dynamic buffer overflow valve for pressure relief and oil replenishment, thereby reducing the startup impact and stop impact of the motor and preventing the cab from shaking.

[0025] 4. When the motor stops, if the pressure relief and oil replenishment from the high-pressure port to the negative-pressure port still cannot make up for the pressure at the negative-pressure port, at this time, Port T will replenish oil to the negative-pressure port through the oil return passage to ensure that the pressures at both Port A and Port B are equal, further reducing the startup impact and stop impact of the motor.

[0026] 5. It also includes a static buffer overflow valve. During the operation of the motor, the static buffer overflow valve cannot be opened and remains in the closed state. Once the motor stops running and Port P closes the oil inlet, due to inertia, the high pressure generated at Port A or Port B will flow back to Port T through the static buffer overflow valve. At the same time, the oil will pass through a damper before entering the static buffer overflow valve, thereby filtering the pressure shock at the peak and further reducing the rotational impact when the motor stops. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 is a schematic structural diagram of the rotary buffer valve of the present invention;

[0028] Figure 2 is a schematic structural diagram of the rotary buffer valve from another perspective of the present invention;

[0029] Figure 3 is a cross-sectional view of the rotary buffer valve of the present invention;

[0030] Figure 4 is a cross-sectional view of the reversing valve and the oil return passage of the present invention;

[0031] Figure 5 is a cross-sectional view of the first dynamic buffer overflow valve, the second dynamic buffer overflow valve, the connecting oil passage, the first oil passage, and the second oil passage of the present invention;

[0032] Figure 6 is a hydraulic schematic diagram of the present invention.

[0033] In the figure, 100 is the valve body; 101 is the motor; 102 is the oil inlet chamber; 103 is the first oil passage; 104 is the second oil passage; 110 is the first dynamic buffer overflow valve; 111 is the connecting oil passage; 112 is the oil replenishing check valve; 120 is the second dynamic buffer overflow valve; 130 is the static buffer overflow valve; 140 is the first reversing solenoid valve; 150 is the second reversing solenoid valve; 160 is the hydraulically controlled reversing valve; 170 is the shuttle valve; 180 is the oil return passage; 181 is the A-port oil return chamber; 182 is the B-port oil return chamber; 183 is the first reversing solenoid valve oil return chamber; 200 is the reversing valve; 201 is the one-way damping valve; 210 is the left control cylinder block; 211 is the reversing valve rod; 212 is the guide sleeve; 213 is the reversing spring; 214 is the reversing spring seat; 220 is the left one-way throttle valve; 230 is the right control cylinder block; 240 is the right one-way throttle valve; 250 is the reversing valve sleeve; 251 is the plug; 252 is the return spring; 253 is the one-way steel ball; 254 is the connecting through hole; 255 is the oil passage hole. Specific embodiments

[0034] The following are specific embodiments of the present invention and, in conjunction with the accompanying drawings, further describe the technical methods of the present invention, but the present invention is not limited to these embodiments.

[0035] In this embodiment, the A port and the B port are used to connect to the external motor 101, the P port is the oil inlet port, the T port is the oil return port and is connected to the fuel tank, the a port and the b port are the control oil ports, the P1 port is the externally controlled pressure oil port, the Y port is the brake interface, the L port is the oil drain port and is connected to the fuel tank, and the K port is the pressure measurement port.

[0036] As Figures 1-6 shown, the present invention provides a rotary buffer valve, which includes a valve body 100 provided with an A port, a B port, a P port and a T port. The A port and the B port are respectively used to connect to both ends of the external motor 101, the P port is communicated with the A port or the B port, and the T port is communicated with the A port or the B port.

[0037] Among them, the valve body 100 in this embodiment integrates multiple functions, including:

[0038] A buffer function, which includes a first dynamic buffer overflow valve 110 and a second dynamic buffer overflow valve 120. The A port is connected to the first dynamic buffer overflow valve 110, and the B port is connected to the second dynamic buffer overflow valve 120. The first dynamic buffer overflow valve 110 and the second dynamic buffer overflow valve 120 are connected to each other. Among them, the external motor 101 has two rotation directions. Corresponding to when the oil enters from the P port and flows into the A port, the oil returns from the B port to the T port. When the oil enters from the P port and flows into the B port, the oil returns from the A port to the T port. During actual operation, once the pressure at the A port exceeds the set value of the first dynamic buffer overflow valve 110, the first dynamic buffer overflow valve 110 starts to overflow and flows into the connecting oil passage 111 between the first dynamic buffer overflow valve 110 and the second dynamic buffer overflow valve 120. The opening pressure of the oil replenishing check valve integrated inside the second dynamic buffer overflow valve 120 is extremely low. Therefore, the hydraulic oil in the connecting oil passage 111 opens the oil replenishing check valve integrated inside the second dynamic buffer overflow valve 120 under the action of pressure, so that the pressure at the A port can be relieved. Vice versa.

[0039] An oil replenishing function. In the above buffer function, during the process of relieving pressure between the A port and the B port through the first dynamic buffer overflow valve 110 and the second dynamic buffer overflow valve 120 to play a buffering role, it is achieved through oil replenishment. At the same time, if the pressure relief and oil replenishment between the A port and the B port cannot completely make up for the negative pressure generated at one of the ports, at this time, the oil at the T port will automatically enter the above negative pressure port for oil replenishment under the action of back pressure or atmospheric pressure to prevent the hydraulic motor from sucking air and causing cavitation damage to the hydraulic motor.

[0040] Among them, during actual operation, when the motor 101 starts and stops, due to the inertia of the large inertia system, there are starting shocks and stopping shocks, which cause the cab to shake. In the cab, it is manifested as a sense of being pushed back. The above buffer function and oil replenishing function are aimed at eliminating the starting shock, stopping shock and shock during operation generated when the motor 101 starts and stops;

[0041] Specifically, when the motor 101 starts, if the oil enters from the P port and flows into the A port, at this time, due to the starting inertia and friction of the motor 101, it cannot start rotating instantly, resulting in an increase in the internal cavity pressure on the A port side. At this time, part of the oil in the A port will pass through the first dynamic buffer overflow valve 110 and flow into the second dynamic buffer overflow valve 120. Finally, the oil pushes open the check valve core of the second dynamic buffer overflow valve 120 and then flows back to the T port, thereby achieving the purpose of relieving pressure at the A port, and thus reducing the starting shock. Vice versa. After the oil enters from the P port and flows into the B port, part of the oil in the B port will also push open the check valve core of the first dynamic buffer overflow valve 110 and then flow back to the T port to achieve the purpose of relieving pressure;

[0042] When the motor 101 stops, if the oil entering from the P port flows into the A port, under the action of inertia, the motor 101 will continue to rotate forward, causing a vacuum and negative pressure at the A port. At the same time, the internal cavity volume at the B port is compressed and a high pressure is generated. At this time, the oil in the B port will flow through the second dynamic buffer overflow valve 120, the first dynamic buffer overflow valve 110 and into the A port to make up for the negative pressure at the A port, and at the same time, the B port is also depressurized. Vice versa;

[0043] In addition, the buffer function also includes a static buffer overflow valve 130, one end of which is connected to the A port and the other end is connected to the P port. Specifically, during the operation of the motor 101, the end of the static buffer overflow valve 130 connected to the A port is for oil inlet, and the end connected to the P port is for oil return. At this time, the static buffer overflow valve 130 cannot be opened and is in a closed state. Once the motor 101 stops running and the P port closes the oil inlet, under the action of inertia, the high pressure generated at the A port or B port will flow back to the T port through the static buffer overflow valve 130. At the same time, the oil will pass through a damper before entering the static buffer overflow valve 130, thereby filtering the pressure shock at the peak and further reducing the rotational shock when the motor 101 stops.

[0044] The commutation function includes a commutation valve 200. The P port is connected to the A port or B port through the commutation valve 200. The two ends of the commutation valve 200 are respectively the a port and the b port. By introducing oil through the a port or b port, the connection between the P port and the A port or B port is controlled. Specifically, when the control oil enters from the a port, the control oil will push the commutation valve 200 to make the P port communicate with the A port, and at the same time, the B port communicates with the T port. Vice versa, when the control oil enters from the b port, the control oil will push the commutation valve 200 in the reverse direction to make the P port communicate with the B port, and at the same time, the A port communicates with the T port. Thus, the commutation function is realized, and the working oil entering from the P port can enter the A port or the B port according to the rotation direction requirement of the motor 101;

[0045] Among them, one-way damping valves 201 are provided at both the a port and the b port. When oil enters, the oil pushes open the one-way valve and flows to the commutation valve 200. Its response speed is fast. When the oil flows back to the a port and the b port, the speed of the oil entering is reduced through the damper, thereby achieving the purpose of fast opening and slow closing and playing a role in making the commutation process stable.

[0046] The brake function includes the Y port, the P1 port and the hydraulic control commutation valve 160. When the motor 101 is running, pressure oil is always injected into the P1 port. At this time, since a shuttle valve 170 is provided between the a port and the b port, whether the oil enters from the a port or the b port, it can push open the shuttle valve 170 and enter the hydraulic control commutation valve 160 to make the P1 port communicate with the Y port. At this time, the pressure oil entering from the P1 port can smoothly flow into the Y port. At the same time, a one-way damping valve 201 is also provided at the Y port, and the pressure oil from the P1 port pushes open the one-way valve and enters the Y port;

[0047] Once the oil stops flowing into ports A and B, the brake will automatically reset. At this time, the oil in port Y will flow back to port L after passing through the damping of the one-way damping valve 201. And on the way back to port L, the oil will be divided into two parts. A small amount of oil will enter port L through multiple bypass dampings, and most of the oil will enter port L after passing through the hydraulic control reversing valve 160. In this way, the brake closes slowly to match the final system, and finally there is no impact when the slewing stops.

[0048] The free rotation function includes a first reversing solenoid valve 140 and a second reversing solenoid valve 150. In this embodiment, the first reversing solenoid valve 140 is preferably a two-position two-way reversing solenoid valve, and the second reversing solenoid valve 150 is preferably a two-position three-way reversing solenoid valve. When the first reversing solenoid valve 140 and the second reversing solenoid valve 150 are both opened and ports P, A, and B are all closed, port A is connected to port B, and the entire slewing buffer valve forms a free rotation state. That is to say, the slewing buffer valve stops rotating, but the slewing buffer valve can be manually pushed to make it rotate, which is convenient for manual operation to adjust the position of the slewing buffer valve.

[0049] In summary, the slewing buffer valve in this embodiment integrates buffer function, oil replenishment function, reversing function, brake function, and free rotation function. It has a high integration degree. Only one slewing buffer valve can provide various functions required by the crane, which is more conducive to production and installation. At the same time, the space utilization rate is also improved during installation.

[0050] Preferably, an oil inlet cavity 102, a first oil passage 103, and a second oil passage 104 are provided in the valve body 100. Port P is communicated with the oil inlet cavity 102, and the oil inlet cavity 102 is communicated with the inner cavity of the reversing valve 200 and the static buffer overflow valve 130. Thus, the oil entering from port P can pass through the reversing valve 200 and flow into port A or port B, and it is ensured that the static buffer overflow valve 130 is always in a closed state during the process of oil inlet at port P. In addition, port A is communicated with the first dynamic buffer overflow valve 110 through the first oil passage 103, and port B is communicated with the second dynamic buffer overflow valve 120 through the second oil passage 104. And a connecting oil passage 111 is formed between the first dynamic buffer overflow valve 110 and the second dynamic buffer overflow valve 120. Thus, the purpose of pressure relief and oil replenishment between port A and port B is achieved through the first dynamic buffer overflow valve 110 and the second dynamic buffer overflow valve 120.

[0051] Preferably, the reversing valve 200 includes a left control cylinder block 210 and a right control cylinder block 230. One end of the left control cylinder block 210 is connected to the valve body 100, and a left one-way throttle valve 220 is connected to the other end. The oil port of the left one-way throttle valve 220 is port b, and the left one-way throttle valve 220 communicates with the inner cavity of the left control cylinder block 210. One end of the right control cylinder block 230 is connected to the valve body 100, and a right one-way throttle valve 240 is connected to the other end. The oil port of the right one-way throttle valve 240 is port a, and the right one-way throttle valve 240 communicates with the inner cavity of the right control cylinder block 230.

[0052] Further preferably, the left one-way throttle valve 220 and the right one-way throttle valve 240 have the same structure, and both are provided with a one-way damping valve 201 inside. The one-way damping valve 201 moves to open or close port a and port b, and also plays a role of quick opening and slow closing.

[0053] Preferably, a reversing valve cavity is provided in the valve body 100. The reversing valve 200 further includes a reversing valve sleeve 250. The reversing valve sleeve 250 is movably arranged in the reversing valve cavity, and both ends of the reversing valve sleeve 250 extend into the left control cylinder block 210 and the right control cylinder block 230 respectively. When oil enters from port a or port b, by pushing the reversing valve sleeve 250, the oil inlet cavity 102 is communicated with the first oil passage 103 or the second oil passage 104, and then the P port is communicated with the A port or the B port.

[0054] Further preferably, cavities are provided at both ends of the reversing valve sleeve 250. A plug 251, a return spring 252, a one-way steel ball 253, a connecting through hole 254 and an oil passing hole 255 are arranged in the cavities. The plug 251 is connected to the reversing valve sleeve 250. Both ends of the return spring 252 abut against the plug 251 and the one-way steel ball 253 respectively. The oil passing cavity is communicated with the oil inlet cavity 102. The two connecting through holes 254 are respectively communicated with the first oil passage 103 and the second oil passage 104. The oil passing hole 255 is communicated or cut off from the connecting through hole 254 by the movement of the one-way steel ball 253. Specifically, after oil enters from port a or port b, the oil will push the entire reversing valve sleeve 250 to move until the oil in the oil inlet cavity 102 enters a cavity from the connecting through hole 254. At this time, the oil can push the one-way steel ball 253 to move and make the oil passing hole 255 communicate with the connecting through hole 254. At this time, the oil in the oil inlet cavity 102 can enter the first oil passage 103 or the second oil passage 104 through the connecting through hole 254 and the oil passing hole 255, realizing the communication between the P port and the A port or the B port. Once oil no longer enters from port a or port b, then the one-way steel ball 253 will reset under the action of the return spring 252 and cut off the communication relationship between the oil passing hole 255 and the connecting through hole 254. At this time, the oil entering from the P port cannot enter the A port or the B port.

[0055] Preferably, a reversing valve rod 211, a guide sleeve 212, a reversing spring 213 and a reversing spring seat 214 are arranged in the left control cylinder block 210. The reversing valve rod 211 is inserted into the plug 251 and the two are connected through the guide sleeve 212. The number of reversing spring seats 214 is two and they are respectively connected to the reversing valve rod 211 and the plug 251. The two ends of the reversing spring 213 are connected to the two reversing spring seats 214. When oil enters from port b and enters the left control cylinder block 210, the oil pushes the reversing valve rod 211 to move forward. Then, the reversing valve rod 211 pushes the entire reversing valve sleeve 250 to move towards the right control cylinder block 230 through the plug 251 until the connecting through hole 254 on the left is communicated with the oil inlet cavity 102. The oil entering from port P passes through the connecting through hole 254 and then pushes the one-way steel ball 253 on the left to make the connecting through hole 254 communicate with the oil inlet cavity 102. Then, the oil inlet cavity 102 is communicated with the second oil passage 104, and port P is communicated with port B.

[0056] Preferably, the right control cylinder block 230 is provided with a cavity inside. Similarly, when oil enters from port a, the oil enters the cavity of the right control cylinder block 230 and directly pushes the plug 251 and the reversing valve sleeve 250 to move towards the left control cylinder block 210 until the oil inlet cavity 102 is communicated with the first oil passage 103, and port P is communicated with port A.

[0057] Preferably, the valve body 100 is further provided with a port T and an oil return passage 180. The oil return passage 180 has three passage openings and all are communicated with port T. At the same time, an oil return cavity 181 for port A and an oil return cavity 182 for port B are further arranged in the reversing valve cavity. Two of the passage openings of the oil return passage 180 are respectively communicated with the oil return cavity 181 for port A and the oil return cavity 182 for port B. By moving the reversing valve sleeve 250, the oil return cavity 181 for port A is communicated with the first oil passage 103 or the oil return cavity 182 for port B is communicated with the second oil passage 104;

[0058] Specifically, when port a or port b is the oil inlet, the reversing valve sleeve 250 is in the initial position, and port P is communicated with both port A and port B. When oil enters from port a, it pushes the reversing valve sleeve 250 to move towards the left control cylinder block 210. At this time, port P is communicated with port A, and at the same time, the oil return cavity 182 for port B is conducted with the second oil passage 104. Thus, the oil at port B can enter the oil return passage 180 through the second oil passage 104 and the oil return cavity 182 for port B and finally flow into port T. Vice versa;

[0059] In addition, a first reversing solenoid valve oil return cavity 183 is further arranged at the middle position of the reversing valve cavity. When the first reversing solenoid valve 140 is energized, the oil inside it can flow into the first reversing solenoid valve oil return cavity 183 and then flow into port T through the oil return passage 180.

[0060] Furthermore, the oil return passage 180 is directly communicated with the first oil passage 103 and the second oil passage 104, and two oil replenishing one-way valves 112 are arranged in the connecting oil passage 111. When a negative pressure is generated at port A or port B and the pressure of the negative pressure port still cannot be compensated after pressure relief and oil replenishment at the other high-pressure port, the oil return passage 180 directly replenishes oil to the negative pressure port through the oil replenishing one-way valves 112.

[0061] The technical means disclosed in the solution of the present invention are not limited to the technical means disclosed by the above technical means, but also include technical solutions composed of any combination of the above technical features. The above is the specific implementation manner of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the principle of the present invention, several improvements and retouches can be made, and these improvements and retouches are also regarded as the protection scope of the present invention.

[0062] It should be noted that all directional indications (such as up, down, left, right, front, back...) in the embodiments of the present invention are only used to explain the relative position relationship and movement conditions between components in a specific posture (as shown in the drawings). If the specific posture changes, the directional indications will also change accordingly.

[0063] In addition, in the present invention, descriptions such as "first", "second", "one" are only for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the quantity of the indicated technical features. Thus, features defined with "first" and "second" may explicitly or implicitly include at least one such feature. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise specifically defined.

[0064] In the present invention, unless otherwise clearly specified and limited, terms such as "connection" and "fixation" should be understood in a broad sense. For example, "fixation" can be a fixed connection, a detachable connection, or integrated; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and can be the internal communication of two components or the interaction relationship between two components, unless otherwise clearly limited. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific situations.

[0065] In addition, the technical solutions between the various embodiments of the present invention can be combined with each other, but it must be based on the fact that those of ordinary skill in the art can implement them. When the combination of technical solutions results in contradictions or cannot be implemented, it should be considered that such a combination of technical solutions does not exist and is not within the protection scope required by the present invention.

Claims

1. A rotary buffer valve, comprising a valve body, which is provided with a port A, a port B, a port P and a port T. The port A and the port B are respectively used for connecting to both ends of an external motor. The port P is communicated with the port A or the port B, and the port T is communicated with the port A or the port B. It is characterized in that, The valve body integrates multiple functions, including: A buffering function, which includes a first dynamic buffering overflow valve, a second dynamic buffering overflow valve, and a static buffering overflow valve. The A port, the first dynamic buffering overflow valve, the second dynamic buffering overflow valve, and the B port are connected and communicated. When the motor starts and generates a starting impact, the pressure between the A port and the B port is released through the first dynamic buffering overflow valve and the second dynamic buffering overflow valve. One end of the static buffering overflow valve is connected to the A port and the other end is connected to the P port. When the motor stops and generates a stopping impact, the oil in the A port or the B port flows back to the T port through the static buffering overflow valve. An oil replenishing function. When the motor stops, the pressure between the A port and the B port is released and replenished with oil through the first dynamic buffering overflow valve and the second dynamic buffering overflow valve. At the same time, the T port replenishes oil to the A port or the B port. A commutation function, which includes a commutation valve. The P port is connected to the A port or the B port through the commutation valve. The two ends of the commutation valve are respectively an a port and a b port. By introducing oil through the a port or the b port, the connection between the P port and the A port or the B port is controlled. A free rotation function, which includes a first commutation solenoid valve and a second commutation solenoid valve. When the first commutation solenoid valve and the second commutation solenoid valve are both opened and the P port, the a port, and the b port are all closed, the A port and the B port are connected through the first commutation solenoid valve and the second commutation solenoid valve. A brake function, which includes a Y port, a P1 port, and a hydraulically controlled commutation valve. When oil enters through the a port or the b port, the hydraulically controlled commutation valve is pushed to move and the P1 port is connected to the Y port.

2. The swing buffer valve according to claim 1, characterized in that, An oil inlet chamber, a first oil passage, and a second oil passage are provided in the valve body. The P port is connected to the oil inlet chamber. The oil inlet chamber is connected to the commutation valve and the static buffering overflow valve. The A port is connected to the first dynamic buffering overflow valve through the first oil passage. The B port is connected to the second dynamic buffering overflow valve through the second oil passage. A connecting oil passage is provided between the first dynamic buffering overflow valve and the second dynamic buffering overflow valve.

3. The swing buffer valve according to claim 2, characterized in that, The commutation valve includes a left control cylinder block and a right control cylinder block. One end of the left control cylinder block is connected to the valve body and the other end is connected with a left one-way throttle valve. The oil port of the left one-way throttle valve is the b port, and the left one-way throttle valve is communicated with the inner cavity of the left control cylinder block. One end of the right control cylinder block is connected to the valve body and the other end is connected with a right one-way throttle valve. The oil port of the right one-way throttle valve is the a port, and the right one-way throttle valve is communicated with the inner cavity of the right control cylinder block.

4. A rotary buffer valve according to claim 3, characterized in that, The left one-way throttle valve and the right one-way throttle valve have the same structure, and both are provided with a one-way damping valve inside. The a port and the b port are opened or closed by the movement of the one-way damping valve, and a damping is also provided inside the one-way damping valve.

5. The swing buffer valve according to claim 4, characterized in that, A reversing valve cavity is provided inside the valve body. The reversing valve further includes a reversing valve sleeve which is movably arranged inside the reversing valve cavity, and both ends of the reversing valve sleeve extend into the left control cylinder body and the right control cylinder body respectively.

6. The rotary buffer valve according to claim 5, wherein, Cavities are provided at both ends of the reversing valve sleeve. A plug, a return spring, a one-way steel ball, a connecting through hole and an oil passage are provided inside the cavities. The plug is connected to the reversing valve sleeve. Both ends of the return spring abut against the plug and the one-way steel ball respectively. The oil passage communicates with the oil inlet chamber. The two connecting through holes communicate with the first oil passage and the second oil passage respectively. The communication or cut-off between the oil passage and the connecting through hole is realized by the movement of the one-way steel ball.

7. A rotary buffer valve according to claim 6, characterized in that, A reversing valve rod, a guide sleeve, a reversing spring and a reversing spring seat are provided inside the left control cylinder body. The reversing valve rod is inserted into the plug and the two are connected through the guide sleeve. Two reversing spring seats are provided and are respectively connected to the reversing valve rod and the plug. Both ends of the reversing spring are connected to the two reversing spring seats. The oil entering from port b pushes the reversing valve rod to move. The reversing valve rod pushes the reversing valve sleeve to move towards the direction of the right control cylinder body through the plug and makes the oil inlet chamber communicate with the second oil passage.

8. A rotary buffer valve according to claim 6, characterized in that, The inside of the right control cylinder body is arranged as a cavity. The oil entering from port a pushes the reversing valve sleeve to move towards the direction of the left control cylinder body through the plug and makes the oil inlet chamber communicate with the first oil passage.

9. A rotary buffer valve according to claim 5, characterized in that, The valve body is further provided with an oil return passage which communicates with port T and the reversing valve cavity. At the same time, an oil return chamber for port A and an oil return chamber for port B are further provided inside the reversing valve cavity. The communication between the oil return chamber for port A and the first oil passage or the communication between the oil return chamber for port B and the second oil passage is realized by the movement of the reversing valve sleeve.

10. A rotary buffer valve according to claim 1, characterized in that, The valve body is further provided with port L which communicates with the second reversing solenoid valve and the hydraulic control reversing valve.

Images