Hydraulic system for controlling pressurization and decompression through pressure difference

Abstract

The utility model relates to the technical field of hydraulic rods, in particular to a hydraulic system utilizing pressure difference to control pressurization and decompression, which comprises an oil cylinder main body, a piston cavity is formed at one end of the oil cylinder main body, a plunger pump and a crusty pancake are fixed at the other end of the oil cylinder main body, and a decompression chamber and a pressure regulating chamber are arranged between the piston cavity and the crusty pancake. The plunger pump is fixed in the crusty pancake and communicated with the pressure relief chamber and the pressure regulating chamber in parallel through the oil inlet channel, and the crusty pancake is communicated with the pressure relief chamber through the oil passing channel. The plunger pump has the beneficial effects that the maximum pushing force pushed out by the piston rod can be adjusted through the pressure adjusting spring below the pressure adjusting cover, and the pressure relief channel is opened or closed by increasing the pressure relief chamber and utilizing pressure difference, so that the pressure relief channel can be quickly blocked after the plunger pump is restarted in the pressure relief process; and the piston rod can stop and extend again without waiting for complete retraction of the piston rod, so that the repeated extension time of the piston rod is shortened, and the working efficiency is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of hydraulic rods, in particular to a hydraulic system which utilizes pressure difference to control pressure increase and pressure relief. Background Art

[0002] A hydraulic cylinder is a device that uses hydraulic principles to achieve mechanical movement. It is widely used in engineering machinery, aerospace, marine engineering, port machinery, automotive industry, machine tool industry, metallurgy industry, and other fields.

[0003] In the prior art, when the piston rod in a hydraulic cylinder driven by hydraulic oil is depressurized and retracted after being extended, the piston rod relies on a return spring to push the piston rod to retract. In the automatic reset hydraulic system, since there is only one pressure relief channel, the pressure relief oil circuit will not be closed until the hydraulic oil in the piston chamber stops flowing during reset, and the pressure can be applied again to extend the cylinder. This method causes the piston rod of the hydraulic cylinder with a long telescopic range to wait for a long time during repeated extension operations, affecting the operation speed and efficiency. Utility Model Content

[0004] In order to solve the above problems, the utility model proposes a hydraulic system which utilizes pressure difference to control pressure increase and pressure release.

[0005] The technical solution of the present utility model is achieved as follows:

[0006] and a tube connecting the dischar e side of the pump with a plug in the forward end of the crank case, said tube having a check valve in it at the pump end, and said former tube which connects the pump to the oil drain plug, said former tube which connects the pump to the oil drain plug, and said former tube which connects the pump to the oil drain plug, said former tube which connects the pump to the oil drain plug, and said former tube which connects the pump to the oil drain plug.

[0007] A pressure differential valve needle is movably installed at the hole connecting the pressure relief chamber and the oil inlet channel, and a pressure differential valve seat is installed at one end of the pressure relief chamber away from the pressure differential valve needle through a threaded connection. A connecting channel connecting the inner cavity of the pressure relief chamber and the oil passage is formed in the pressure differential valve seat, and a conical plug that can block the connecting channel is formed at the end of the pressure differential valve needle, and the oil relief channel is connected to the cavity between the pressure differential valve needle and the pressure differential valve seat;

[0008] A pressure-regulating valve seat is installed at the hole where the pressure-regulating chamber is connected to the oil inlet channel through a threaded connection, and an oil through hole connecting the oil inlet channel and the pressure-regulating chamber is formed on the pressure-regulating valve seat, and a pressure-regulating cover is threadedly connected or inserted at one end of the pressure-regulating chamber away from the pressure-regulating valve seat, a pressure-regulating valve needle is slidably installed at the center of the pressure-regulating cover, and a damping plate is slidably installed on the outside of the end of the pressure-regulating valve needle close to the pressure-regulating valve seat, a pressure-regulating spring nested on the outer wall of the pressure-regulating valve needle is provided between the damping plate and the pressure-regulating cover, the elastic force of the pressure-regulating spring is greater than the elastic force of the second spring, and a conical plug that can block the oil through hole is formed on the end of the pressure-regulating valve needle facing the pressure-regulating valve seat, and the two first oil return holes are connected in the pressure-regulating chamber.

[0009] Furthermore, a sealing ring is fixed on the outer wall of the pressure differential valve needle and the pressure differential valve seat.

[0010] Furthermore, a sealing ring is fixed on the outer wall of the pressure regulating cover.

[0011] Furthermore, the blocking device is a steel ball or a valve needle.

[0012] Furthermore, a piston rod with a piston sealing groove is slidably installed in the piston cavity, a sealing ring is installed in the piston sealing groove, and a reset spring is nested on the piston rod to cause the piston rod to reset.

[0013] By adopting the above technical solution, the beneficial effects of the utility model are:

[0014] By adjusting the pressure regulating cover, the compression amount of the pressure regulating spring is changed, and the force of the pressure regulating valve needle sealing the pressure regulating valve seat is set, thereby the maximum pressure of the hydraulic system can be adjusted. By increasing the pressure relief chamber, the pressure difference is used to drive the action of the pressure differential valve needle, thereby realizing the opening or closing of the oil drain channel. In the process of pressure relief, the hydraulic oil does not need to continuously open the return oil channel through the pressure regulating valve needle, but returns the hydraulic oil to the oil well through the newly added oil drain channel. After restarting the plunger pump, the oil drain channel can be quickly blocked. During the retraction process of the piston rod, the retraction action can be stopped at any time and re-extended without waiting until the piston rod is fully retracted. This shortens the time for repeated extension of the piston rod and improves working efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0016] Figure 1 It is a main sectional view of the utility model;

[0017] Figure 2 This is a schematic diagram of the connection between the pressure relief chamber and the pressure regulating chamber of the utility model;

[0018] Figure 3 This is a schematic diagram of the connection between the oil-fried bread and the surge chamber of the utility model;

[0019] Figure 4 This is an independent design structure diagram of the elastic sealing mechanism of the utility model.

[0020] The following are the descriptions of the reference numerals:

[0021] 1. Cylinder body; 2. Piston chamber; 3. Plunger pump; 4. Oil inlet channel; 5. Pressure relief chamber; 51. Pressure differential valve needle; 52. Pressure differential valve seat; 53. Connecting channel; 54. Oil passage; 6. Pressure regulating chamber; 61. Pressure regulating valve seat; 62. Pressure regulating cover; 63. Pressure regulating valve needle; 64. Oil through hole; 65. Damping plate; 66. Pressure regulating spring; 67. First oil return hole; 7. Oil sump; 8. Oil filling channel; 81. Hollow screw; 82. Second spring; 83. Sealing device; 9. Oil relief channel. DETAILED DESCRIPTION

[0022] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0023] like Figure 1-Figure 3As shown, a hydraulic system that uses pressure difference to control pressure increase and pressure relief includes a cylinder body 1, a piston chamber 2 is formed at one end of the cylinder body 1, a piston with a piston rod fixed thereto is slidably installed in the piston chamber 2, a plunger pump 3 and an oil naan 7 are fixed at the other end of the cylinder body 1, the oil naan 7 is used to store hydraulic oil, a pressure relief chamber 5 and a pressure regulating chamber 6 are provided between the piston chamber 2 and the oil naan 7, a pressure regulating mechanism is fixed in the pressure regulating chamber 6, the plunger pump 3 is fixed in the oil naan 7, the plunger pump 3 is connected to the pressure relief chamber 5 and the pressure regulating chamber 6 through the oil inlet channel 4, and the plunger pump A one-way valve is installed between 3 and the oil inlet channel 4 to ensure one-way flow of hydraulic oil. The oil naan 7 is connected to the pressure relief chamber 5 through the oil passage 54. The oil naan 7 is connected to the pressure regulating chamber 6 through two first oil return holes 67. The oil inlet channel 4 is connected to the piston chamber 2 through the oil injection channel 8. The piston chamber 2 is connected to the pressure relief chamber 5 through the oil leakage channel 9. An elastic sealing mechanism is installed at the oil injection channel 8. The elastic sealing mechanism is built into the side of the oil injection channel 8 close to the piston chamber 2 or is a separate component and is installed at one end of the oil injection channel 8 close to the piston chamber 2 by threading (such as Figure 4 The elastic sealing mechanism includes a hollow screw 81, a second spring 82 and a steel ball 83. The hollow screw 81 is threadedly mounted on one end of the oil injection channel 8 close to the piston chamber 2. The steel ball 83 is rollingly or slidingly mounted on one end of the oil injection channel 8 close to the oil inlet channel 4. The second spring 82 is mounted between the hollow screw 81 and the steel ball 83. The steel ball 83 can enable the hydraulic oil to flow in one direction in the oil injection channel 8, that is, from the oil inlet channel 4 through the oil injection channel 8 to the piston chamber 2, and the reverse flow is cut off. When the pressure in the oil inlet channel 4 is greater than the pressure in the piston chamber 2, the hydraulic oil can push the steel ball 83 away, so that the oil in the oil inlet channel 4 enters the piston chamber 2 and pushes the piston rod to extend.

[0024] A pressure differential valve needle 51 is movably installed at the hole connecting the pressure relief chamber 5 and the oil inlet channel 4. A pressure differential valve seat 52 is installed at the end of the pressure relief chamber 5 away from the pressure differential valve needle 51 through a threaded connection. An oil passage 54 and a connecting channel 53 communicating with the inner cavity of the pressure relief chamber 5 are formed in the pressure differential valve seat 52. A conical plug that can block the connecting channel 53 is formed at the end of the pressure differential valve needle 51. The oil relief channel 9 is connected to the cavity between the pressure differential valve needle 51 and the pressure differential valve seat 52. When the pressure in the oil inlet channel 4 is high, the pressure differential valve needle 51 can be pushed to block the connecting channel 53 to prevent the oil in the piston chamber 2 from flowing into the pressure relief chamber 5 through the oil leakage channel 9 and then being discharged into the oil chamber 7 through the connecting channel 53;

[0025] The pressure regulating mechanism includes a pressure regulating valve seat 61 installed at the hole connecting the pressure regulating chamber 6 and the oil inlet channel 4 through a threaded connection, and an oil through hole 64 connecting the oil inlet channel 4 and the pressure regulating chamber 6 is formed on the pressure regulating valve seat 61. The end of the pressure regulating chamber 6 away from the pressure regulating valve seat 61 is connected or inserted with a pressure regulating cover 62 through a threaded connection, and a pressure regulating valve needle 63 is slidably installed in the center of the pressure regulating cover 62. A damping plate 65 is slidably installed on the outside of the end of the pressure regulating valve needle 63 close to the pressure regulating valve seat 61, and a pressure regulating spring 66 nested on the outer wall of the pressure regulating valve needle 63 is provided between the damping plate 65 and the pressure regulating cover 62. The pressure regulating spring 66 is in a compressed state, and the end of the pressure regulating valve needle 63 facing the pressure regulating valve seat 61 is formed with a spring that can block the oil through hole 64 Conical blockage, the pressure regulating valve needle 63 is pressed on the pressure regulating valve seat 61 by the pressure regulating spring 66 to block the oil hole 64. By adjusting the upper and lower positions of the pressure regulating cover 62, the compression amount of the pressure regulating spring 66 is determined, and then the force applied by the pressure regulating spring 66 to the pressure regulating valve needle 63 is determined, and the maximum pressure of the entire system is determined. The elastic force of the pressure regulating spring 66 is greater than the elastic force of the second spring 82. When the damping plate 65 moves, at least one of the two first oil return holes 67 is connected to the oil pan 7, so that the oil in the pressure regulating chamber 6 can return to the oil pan 7. The two first oil return holes 67 are staggered, so that the oil can be used to achieve a damping effect when the damping plate 65 moves, thereby avoiding the damping plate 65 moving too fast and affecting oil leakage.

[0026] When the plunger pump 3 is working, liquid pressure is generated in the oil inlet channel 4. Since the pressure regulating valve needle 63 blocks the channel connecting the oil nut 7 on the pressure regulating valve seat 61, the hydraulic oil can only push the pressure differential valve needle 51 forward and block the connecting channel 53 connecting the oil nut on the pressure differential valve seat 52. At this time, since the force of the pressure regulating spring 66 is much greater than the elastic force of the second spring 82, the hydraulic oil will push open the elastic sealing mechanism, discharge oil to the piston chamber 2, and push the piston rod forward. As the load in front of the piston rod increases, the system pressure increases accordingly. When the system pressure is greater than the set pressure, the oil pressure in the system will increase. When the pressure regulating valve needle 63 is opened, the hydraulic oil will overcome the force of the pressure regulating spring 66 and push the pressure regulating valve needle 63 upward. At this time, the sealing device 83 seals the hydraulic oil in the piston chamber under the action of the second spring 82. The pressure in the oil inlet channel 4 flows back to the oil container through the first oil return hole 67 as the pressure regulating valve needle 63 opens. After the force that pushes the pressure differential valve needle 51 to seal the pressure differential valve seat 52 is released, the pressure differential valve needle 51 can no longer seal the oil and opens. The hydraulic oil in the piston chamber 2 flows back to the oil container 7 through the oil drain channel 9 and the channel on the pressure differential valve seat 52.

[0027] In this embodiment, the diameter of the oil drain channel 9 is larger than the smallest diameter of the oil through hole 64 on the pressure regulating valve seat 61 , so as to facilitate rapid oil drain and retraction during pressure relief.

[0028] In this embodiment, in order to improve the sealing performance, sealing rings are fixed on the outer walls of the pressure differential valve needle 51 and the pressure differential valve seat 52 .

[0029] In this embodiment, in order to improve the sealing performance, a sealing ring is fixed on the outer wall of the pressure regulating cover 62.

[0030] In this embodiment, a piston rod with a piston sealing groove is slidably installed in the piston chamber 2, a sealing ring is installed in the piston sealing groove, and a return spring is nested on the piston rod to cause the piston rod to return to its original position, so that the piston rod can automatically return to the piston chamber 2 in the pressure relief state.

[0031] The working principle of the present invention is as follows: when in use, when the hydraulic rod needs to be extended, the plunger pump 3 is started, and the plunger pump 3 pumps the oil in the oil naan 7 into the oil inlet channel 4. When the high-pressure oil flows in the oil inlet channel 4, it pushes the pressure differential valve needle 51 to move toward the pressure differential valve seat 52 to block the connecting channel 53, so that the oil flowing back from the oil drain channel 9 will not flow back into the oil naan 7 through the connecting channel 53 and the oil passage 54. At the same time, since the elastic force of the pressure regulating spring 66 is greater than the elastic force of the second spring 82, the pressure regulating valve needle 63 blocks the oil through hole 64 under the action of the pressure regulating spring 66. The oil cannot enter the pressure regulating chamber 6. As the oil pressure increases, the hydraulic oil pushes the steel ball 83 to move toward the hollow screw 81, thereby opening the oil filling channel 8. The high-pressure oil enters the piston chamber 2, pushing the piston to move and driving the piston rod to extend. When the hydraulic rod is extended to a certain length and wants to pause, the plunger pump 3 can be stopped. After the plunger pump 3 stops, due to the elastic sealing mechanism and the unidirectional action of the plunger pump 3, the pressure in the oil inlet channel 4 is constant. The pressure differential valve needle 51 can always seal the connecting channel 53 on the pressure differential valve seat 52, the hydraulic rod stops extending, and the pressure is maintained. When When the hydraulic rod needs to be retracted, after stopping the plunger pump 3, the pressure regulating valve needle 63 is manually opened, and the hydraulic oil in the oil inlet channel 4 will return to the oil chamber 7 through the oil through hole 64 and the first oil return hole 67. At the same time, due to the one-way effect of the elastic sealing mechanism, the pressure in the piston chamber 2 cannot affect the oil inlet channel 4. Since the pressure in the oil inlet channel 4 becomes smaller, the pressure differential valve needle 51 can no longer seal the pressure differential valve seat 52 and the pressure relief channel is opened. The hydraulic oil in the piston chamber 2 flows into the pressure relief chamber 5 through the oil relief channel 9, and then flows into the oil chamber 7 through the connecting channel 53 and the oil passage 54 to relieve the pressure. The pressure rod gradually retracts under the action of the return spring. When the hydraulic rod is extended to the maximum stroke, or the internal pressure of the system reaches the set value of the pressure regulating spring 66, the pressure in the oil inlet channel 4 will rush open the pressure regulating valve needle 63 to release the pressure. Due to the action of the damping plate 65, the pressure regulating valve needle 63 cannot be closed instantaneously, ensuring that the pressure difference between the piston chamber 2 and the oil inlet channel 4 is large enough. After the pressure is released, the pressure differential valve needle 51 can no longer seal the connecting channel 53 on the pressure differential valve seat 52 and is opened. The hydraulic oil in the piston chamber 2 flows back to the oil chamber 7 under the action of the return spring.

[0032] The present application uses the pressure differential valve needle 51 to open or close the oil drain channel 9 without relying on the pressure regulating valve needle 63 to remain open. After the plunger pump 3 stops working, the pressure in the oil inlet channel 4 will pass through the pressure regulating valve needle 63 to open, and then pass through the 64 channel on the pressure regulating valve seat 61 to return to the pressure regulating chamber and then to the oil chamber. Since the pressure regulating valve needle 63 will reset quickly after the pressure is released, the damping plate 65 is set to delay the reset time of the pressure regulating valve needle 63, so that the pressure difference at both ends of the pressure differential valve needle 51 can be large enough to allow the pressure differential valve needle 51 to leave the pressure differential valve seat 52 and open the oil drain channel 9. Since the pressure regulating valve needle 63 is in a state of sealing the pressure regulating valve seat 61 when the piston rod is depressurized, the plunger pump can be restarted at any time to push the piston rod forward without waiting for the piston rod to fully retract. The piston rod can continue to extend at any position when retracting, realizing the function of continuous operation and improving work efficiency.

[0033] Components not described in detail herein are prior art.

[0034] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A hydraulic system that uses pressure difference to control pressure increase and pressure relief, characterized by: The invention comprises an oil cylinder body (1), wherein a piston cavity (2) is formed at one end of the oil cylinder body (1), and a plunger pump (3) and an oil naan (7) are fixed at the other end of the oil cylinder body (1), and a pressure relief chamber (5) and a pressure regulating chamber (6) are provided between the piston cavity (2) and the oil naan (7), wherein the plunger pump (3) is fixed in the oil naan (7), and the plunger pump (3) is connected to the pressure relief chamber (5) and the pressure regulating chamber (6) in parallel through an oil inlet channel (4), and the oil naan (7) is connected to the pressure relief chamber (5) through an oil passage (54), and the oil naan (7) is connected to the pressure regulating chamber (6) through two first oil return holes (67), and the oil inlet channel (4) is connected to the pressure relief chamber (5). The piston chamber (2) is connected to the oil injection channel (8), and the piston chamber (2) is connected to the pressure relief chamber (5) through the oil leakage channel (9). An elastic blocking mechanism is installed at the oil injection channel (8), and the elastic blocking mechanism includes a hollow screw (81), a second spring (82) and a blocking device (83). The hollow screw (81) is installed at one end of the oil injection channel (8) close to the piston chamber (2) through a thread. The blocking device (83) is installed in a rolling or sliding manner at one end of the oil injection channel (8) close to the oil inlet channel (4). The second spring (82) is installed between the hollow screw (81) and the blocking device (83). A pressure differential valve needle (51) is movably installed at the hole connecting the pressure relief chamber (5) and the oil inlet channel (4); a pressure differential valve seat (52) is installed at one end of the pressure relief chamber (5) away from the pressure differential valve needle (51) through a threaded connection; a connecting channel (53) is formed in the pressure differential valve seat (52) for connecting the inner cavity of the pressure relief chamber (5) and the oil passage (54); a conical plug is formed at the end of the pressure differential valve needle (51) for plugging the connecting channel (53); and the oil relief channel (9) is connected to the cavity between the pressure differential valve needle (51) and the pressure differential valve seat (52); A pressure regulating valve seat (61) is installed at the hole where the pressure regulating chamber (6) is connected to the oil inlet channel (4) through a threaded connection. An oil through hole (64) connecting the oil inlet channel (4) and the pressure regulating chamber (6) is formed on the pressure regulating valve seat (61). A pressure regulating cover (62) is connected or inserted at one end of the pressure regulating chamber (6) away from the pressure regulating valve seat (61) through a threaded connection. A pressure regulating valve needle (63) is slidably installed at the center of the pressure regulating cover (62). The pressure regulating valve needle (63) is close to the pressure regulating valve seat (6 1) is slidably mounted on the outside of one end of the pressure regulating valve needle (63), and a pressure regulating spring (66) is provided between the damping plate (65) and the pressure regulating cover (62) and is nested on the outer wall of the pressure regulating valve needle (63). The elastic force of the pressure regulating spring (66) is greater than the elastic force of the second spring (82). The end of the pressure regulating valve needle (63) facing the pressure regulating valve seat (61) is formed with a conical plug capable of blocking the oil through hole (64), and the two first oil return holes (67) are connected in the pressure regulating chamber (6).

2. A hydraulic system for controlling pressure increase and pressure relief using pressure difference according to claim 1, characterized in that: Sealing rings are fixed on the outer walls of the pressure differential valve needle (51) and the pressure differential valve seat (52).

3. The hydraulic system for controlling pressure increase and pressure relief using pressure difference according to claim 1, characterized in that: A sealing ring is fixed on the outer wall of the pressure regulating cover (62).

4. The hydraulic system for controlling pressure increase and pressure relief using pressure difference according to claim 1, characterized in that: The blocking device (83) is a steel ball or a valve needle.

5. The hydraulic system for controlling pressure increase and pressure relief using pressure difference according to claim 1, characterized in that: A piston rod with a piston sealing groove is slidably installed in the piston cavity (2), a sealing ring is installed in the piston sealing groove, and a reset spring for causing the piston rod to reset is nested on the piston rod.

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