A double-acting ultra-high-pressure hydraulic pump suitable for double-acting hydraulic tensioners

Abstract

The present invention discloses a double-acting ultra-high-pressure hydraulic pump suitable for a double-acting hydraulic tensioner. The pump comprises an oil tank and a handle frame, the handle frame being fixed to the top of the oil tank. A motor is disposed within the inner cavity of the handle frame. The lower end of the motor output shaft is connected to a pump valve assembly within the inner cavity of the oil tank. The pump valve assembly is provided with a high-pressure oil circuit and a low-pressure oil circuit, each of which is connected to an output valve block and an oil inlet of a hydraulic control valve block via oil pipes. The output valve block is provided with a two-position, two-way solenoid valve, a hydraulically controlled one-way valve, a throttle valve, a hydraulically controlled stop valve, a pressure gauge, and a pressure regulating valve. The hydraulic control valve block is provided with a two-position, four-way solenoid valve. An electrical control box is disposed on one side of the rear of the motor and is fixed to the handle frame. A heat sink is fixedly disposed on one side of the motor, and a cooling fan is fixedly disposed on one side of the outer wall of the heat sink. The present invention controls the switching action of the two solenoid valves by the electrical control box, thereby achieving two operating states: high-pressure output and low-pressure oil return; and low-pressure output and high-pressure oil return.

Description

Technical Field

[0001] The invention belongs to the field of hydraulic technology and relates to a driving device of a double-acting hydraulic stretcher, in particular to a double-acting hydraulic pump. Background Art

[0002] Hydraulic tensioners are divided into single-acting hydraulic tensioners and double-acting hydraulic tensioners according to the different piston reset methods. The single-acting hydraulic tensioner has only one oil inlet and outlet interface on the oil cylinder to push the piston forward, and the reverse reset of the piston is achieved by spring drive. The disadvantage of this structure is that when the spring force is large, on the one hand, it causes a large resistance to the forward movement of the piston, and the hydraulic pump does a lot of useless work. On the other hand, the excessive spring force has a non-negligible effect on the output tension of the hydraulic tensioner, affecting the output accuracy of the tensioner. Therefore, single-acting hydraulic tensioners generally choose a reset spring with a relatively small force, which can reduce useless work and effectively reduce the influence of the spring force on the output accuracy of the hydraulic tensioner. However, the small spring force causes the piston to reset slowly, which affects the work efficiency of the bolt tightening operation.

[0003] The oil cylinder of the double-acting hydraulic tensioner is provided with oil inlet and outlet ports on both sides of the piston. The oil inlet of the first port pushes the piston to move forward, while the oil is returned to the second port. When the piston needs to be reset in the reverse direction, the oil inlet of the second port pushes the piston to move in the reverse direction, and the oil is returned to the first port. Compared with the single-acting hydraulic tensioner, the double-acting hydraulic tensioner uses a hydraulic pump instead of a reset spring, and only feeds oil when resetting. That is, there is no wasted work and it does not affect the output accuracy of the hydraulic tensioner. The piston can be quickly reset by controlling the reset pressure.

[0004] Although double-acting hydraulic tensioners have many advantages in terms of use, they require two hydraulic pumps when used, which is very expensive. In order to solve the high cost problem of double-acting hydraulic tensioners, the existing solution is to design a double-acting high-pressure hydraulic pump. On the basis of the original single-output high-pressure hydraulic pump, a low-pressure working oil port is added to the low-pressure section of the output oil circuit. A two-position four-way solenoid valve is used to switch between the two states of high-pressure working oil port output and low-pressure working oil port return oil and low-pressure working oil port output and high-pressure working oil port return oil.

[0005] The disadvantage of this existing solution is that when applied to ultra-high-pressure hydraulic pumps exceeding 100 MPa, at the moment when the high-pressure working oil port begins to return oil, the high-pressure oil will impact the two-position four-way solenoid valve through the return oil line, which can easily damage the two-position four-way solenoid valve. Therefore, there is currently no double-acting ultra-high-pressure hydraulic pump suitable for double-acting hydraulic tensioners with working pressures exceeding 100 MPa. Summary of the Invention

[0006] The purpose of the present invention is to address the problem in the prior art that there is no double-acting ultra-high-pressure hydraulic pump suitable for double-acting hydraulic tensioners with a working pressure of more than 100 MPa, and to provide a double-acting ultra-high-pressure hydraulic pump that can be used for double-acting hydraulic tensioners with a working pressure of more than 100 MPa.

[0007] To achieve the above object, the present invention adopts the following technical solutions:

[0008] A double-acting ultra-high-pressure hydraulic pump suitable for a double-acting hydraulic stretcher, comprising an oil tank, an ultra-high-pressure plunger pair, a low-pressure plunger pair, a high-pressure working oil port, a low-pressure working oil port, and a two-position four-way solenoid valve.

[0009] The oil outlet of the ultra-high pressure plunger pair is unidirectionally connected to the high pressure working oil port through a high pressure output pipeline, and the high pressure working oil port is unidirectionally connected to the oil tank through an oil return pipeline;

[0010] The oil outlet of the low-pressure plunger pair is connected to the oil inlet of the two-position four-way solenoid valve, the first working oil port of the two-position four-way solenoid valve is unidirectionally connected to the high-pressure output pipeline, the second working oil port of the two-position four-way solenoid valve is connected to the low-pressure working oil port, and the oil return port of the two-position four-way solenoid valve is connected to the oil return pipeline;

[0011] It is characterized in that it also includes a two-position two-way solenoid valve, and a throttle valve, a hydraulically controlled stop valve, and a hydraulically controlled one-way valve are provided at the inlet end of the return oil pipeline. The throttle valve and the hydraulically controlled stop valve are connected in series and in parallel with the hydraulically controlled one-way valve. The hydraulic control port of the hydraulically controlled stop valve is connected to the first working oil port of the two-position four-way solenoid valve, the hydraulic control port of the hydraulically controlled one-way valve is connected to the second working oil port of the two-position four-way solenoid valve, the oil inlet of the two-position two-way solenoid valve is connected to the first working oil port of the two-position four-way solenoid valve, and the oil outlet of the two-position two-way solenoid valve is connected to the oil return pipeline.

[0012] The above technical solution adopts a throttle valve, a hydraulically controlled stop valve, a hydraulically controlled check valve, and a two-position two-way solenoid valve to form a structure that can prevent high-pressure shock. On the one hand, the throttle valve and the hydraulically controlled stop valve are used to unload the ultra-high pressure in the high-pressure working oil port. On the other hand, the hydraulically controlled check valve is used to complete the rapid oil return of the high-pressure working oil port, which effectively avoids the problem of high-pressure oil instantly rushing into the return oil pipeline and causing impact on the return oil pipeline and the low-pressure devices connected to it, while ensuring the return oil speed of the high-pressure oil.

[0013] In addition, connecting the hydraulic control port of the hydraulically controlled one-way valve with the second working oil port of the two-position four-way solenoid valve effectively ensures the absolute synchronization of low-pressure output and high-pressure return oil, avoiding the risk of electronic control time difference.

[0014] Furthermore, a handle frame is provided on the top of the oil tank, and a pump body valve group is provided in the oil tank, and the pump body valve group includes the low-pressure plunger pair, the ultra-high-pressure plunger pair, a low-pressure oil outlet, a high-pressure oil outlet, a low-pressure unloading valve, and a low-pressure oil return port;

[0015] The oil outlet of the low-pressure plunger pair is communicated with the low-pressure oil outlet of the pump body valve group, and the oil outlet of the ultra-high-pressure plunger pair is communicated with the high-pressure oil outlet of the pump body valve group. The low-pressure unloading valve is arranged between the low-pressure oil outlet and the low-pressure oil return port of the pump body valve group, and the low-pressure oil return port of the pump body valve group is connected to the inner cavity of the oil tank.

[0016] The above structure integrates the low-pressure plunger pair and the ultra-high-pressure plunger pair into the pump body valve group, effectively reducing the use of oil pipes and joints, making the structure more compact and reducing the risk of interface leakage.

[0017] An output valve group, an electric control box, a motor, a heat sink and a heat dissipation fan are arranged inside the handle frame.

[0018] The motor is fixedly arranged on the top of the oil tank, and the lower end of the motor output shaft extends through the oil tank top cover to the inner cavity of the oil tank. The lower end of the motor output shaft is equipped with a cam for driving the low-pressure plunger pair and the ultra-high-pressure plunger pair.

[0019] The output valve group includes a hydraulically controlled valve block, the two-position four-way solenoid valve, an output valve block, and the two-position two-way solenoid valve.

[0020] The hydraulic control valve block is fixedly arranged on the top of the oil tank, and the two-position four-way solenoid valve is arranged on the hydraulic control valve block. The hydraulic control valve block is provided with a low-pressure oil inlet, a low-pressure oil outlet, the low-pressure working oil port, an oil return outlet, and a hydraulic control oil outlet; the oil inlet, oil return port, and first working oil port of the two-position four-way solenoid valve are respectively communicated with the low-pressure oil inlet, oil return outlet, and low-pressure oil outlet on the hydraulic control valve block through the inside of the valve block; the second working oil port of the two-position four-way solenoid valve is simultaneously communicated with the low-pressure working oil port and the hydraulic control oil outlet on the hydraulic control valve block through the inside of the valve block; the low-pressure oil inlet of the hydraulic control valve block is connected to the low-pressure oil outlet of the pump body valve group through an oil pipe.

[0021] The output valve block is fixedly arranged on the top of the oil tank, the two-position two-way solenoid valve is arranged on the output valve block, the output valve block is provided with a low-pressure oil inlet, a high-pressure oil inlet, a hydraulically controlled oil inlet, a return oil inlet, a return oil outlet, and the high-pressure working oil port, and the throttle valve, the hydraulically controlled stop valve, and the hydraulically controlled one-way valve are arranged in the output valve block.

[0022] The high-pressure oil inlet of the output valve block is connected to the high-pressure oil outlet of the pump body valve group through an oil pipe.

[0023] The high-pressure oil inlet of the output valve block is unidirectionally connected to the high-pressure working oil port through a one-way valve inside the valve block, and the low-pressure oil inlet of the output valve block is unidirectionally connected to the high-pressure oil inlet of the output valve block through a one-way valve inside the valve block.

[0024] The inlet of the throttle valve and the inlet of the hydraulically controlled one-way valve are respectively communicated with the high-pressure working oil port inside the valve block, the outlet of the throttle valve is connected to the inlet of the hydraulically controlled stop valve, and the outlet of the hydraulically controlled one-way valve and the outlet of the hydraulically controlled stop valve are respectively communicated with the return oil outlet of the output valve block inside the valve block.

[0025] The hydraulic control port of the hydraulically controlled stop valve is communicated with the low-pressure oil inlet of the output valve block inside the valve block, the oil inlet of the two-position two-way solenoid valve is communicated with the low-pressure oil inlet of the output valve block through the inside of the valve block, the hydraulic control port of the hydraulically controlled one-way valve is communicated with the hydraulic control oil inlet of the output valve block inside the valve block, and the oil outlet of the two-position two-way solenoid valve is communicated with the return oil outlet of the output valve block through the inside of the valve block.

[0026] The low-pressure oil inlet of the output valve block is connected to the low-pressure oil outlet of the hydraulic control valve block through an oil pipe, the hydraulic control oil inlet of the output valve block is connected to the hydraulic control oil outlet of the hydraulic control valve block, the return oil inlet of the output valve block is connected to the return oil outlet of the hydraulic control valve block, the return oil inlet of the output valve block is connected to the return oil outlet of the hydraulic control valve block, the return oil inlet of the output valve block is connected to the return oil outlet of the output valve block inside the valve block, and the return oil outlet of the output valve block is connected to the inner cavity of the oil tank.

[0027] This structure integrates the connecting channels between the 2 / 4-way solenoid valve, 2 / 2-way solenoid valve, throttle valve, hydraulically controlled shut-off valve, hydraulically controlled check valve, as well as a portion of the high-pressure output pipeline and the oil return pipeline within the hydraulically controlled valve block and the output valve block. This reduces the need for extensive oil piping, resulting in a more compact structure and lowering the risk of interface leakage.

[0028] Furthermore, the heat sink is fixedly arranged on one side of the motor, the heat dissipation fan is fixedly arranged on one side of the outer wall of the heat sink, and the heat dissipation fan is fixedly connected to one side of the handle frame through a connecting rod.

[0029] The electric control box is arranged on one side behind the motor, and is fixedly arranged on the handle frame.

[0030] By adopting the above scheme, the device controls the reversing action of the two solenoid valves through the electronic control box, thereby realizing the switching between the two states of high-pressure output and low-pressure return oil and low-pressure output and high-pressure return oil of the device, and the performance is stable. When the high-pressure output is performed, the low-pressure plunger pair and the ultra-high-pressure plunger pair work to output pressure oil at the same time. When the oil pressure of the oil circuit reaches the set value, the hydraulic oil supplied by the low-pressure plunger pair is unloaded through the low-pressure unloading valve in the hydraulic oil circuit, and the hydraulic oil is output by the ultra-high-pressure plunger pair alone, so that the system is in a high-pressure working state, driving the hydraulic tensioner cylinder piston to move forward. When the hydraulic tensioner is reset, the ultra-high-pressure plunger pair stops working, the two-position four-way solenoid valve performs the switch, the low-pressure working oil port outputs low-pressure oil, and drives the hydraulic tensioner cylinder piston to move in the opposite direction.

[0031] During the operation of the system, a cooling fan is arranged on one side of the motor so that the cooling fan absorbs the heat generated by the operation of the motor during operation, thereby avoiding the device being in a high temperature environment for a long time and thus improving the working time of the device.

[0032] Furthermore, a pressure gauge is fixedly installed on the top of the output valve block, and the oil inlet of the pressure gauge is connected to the high-pressure working oil port of the output valve block. A pressure regulating valve is provided on the right side of the output valve block, and the inlet of the pressure regulating valve is connected to the high-pressure oil inlet of the output valve block.

[0033] By adopting the above technical solution, the setting of the pressure gauge is conducive to detecting the pressure adjusted by the output valve block and is convenient for workers to observe. At the same time, the setting of the pressure regulating valve is conducive to manual pressure adjustment.

[0034] Furthermore, an oil plug cover is provided at the bottom end of the front side of the oil tank, and one end of the oil plug cover passes through a side wall of the oil tank and extends to the inner cavity of the oil tank.

[0035] By adopting the above technical solution, it is beneficial to inject hydraulic oil into the oil tank through the oil plug cover, thereby ensuring that the oil stored in the oil tank can be used for the normal operation of the device.

[0036] Furthermore, a filter is provided around the connection between the bottom end of the motor and the pump body valve group, and the filter is provided in the inner cavity of the oil tank.

[0037] By adopting the above technical solution, the motor can filter the hydraulic oil when working, preventing impurities and particles in the hydraulic oil from entering the pump valve group, thereby affecting the normal operation of the pump or greatly shortening the service life of the pump.

[0038] Furthermore, the motor, solenoid valve and cooling fan are all connected to the connecting end of the electric control box.

[0039] By adopting the above technical solution, it is beneficial to realize dual-action high and low pressure switching, thereby reducing the manual operation process and greatly improving work efficiency.

[0040] The beneficial effects of the present invention are as follows: the device realizes the switching of the ultra-high pressure pump between the two states of high-pressure output and low-pressure oil return and low-pressure output and high-pressure oil return through a two-position four-way solenoid valve; at the same time, through the anti-high-pressure impact structure composed of a throttle valve, a hydraulically controlled stop valve, a hydraulically controlled one-way valve, and a two-position two-way solenoid valve, it ensures that when the high-pressure oil is returned, under the premise of not affecting the return oil speed, the high-pressure oil is prevented from instantaneously rushing into the return oil pipeline to cause impact damage to the return oil pipeline and the low-pressure components connected thereto.

[0041] The above description is only an overview of the technical solution of the present invention. In order to more clearly understand the technical means of the present invention, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present invention more obvious and easy to understand, the following preferred embodiments are specifically cited and described in detail with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] Figure 1 This is a schematic diagram of the overall structure of the double-acting ultra-high-pressure hydraulic pump of the present invention.

[0043] Figure 2 This is a schematic diagram of the top view of the double-acting ultra-high pressure hydraulic pump of the present invention.

[0044] Figure 3 This is a front view structural diagram of the double-acting ultra-high pressure hydraulic pump of the present invention.

[0045] Figure 4 This is a side structural schematic diagram of the double-acting ultra-high pressure hydraulic pump of the present invention.

[0046] Figure 5 This is a schematic diagram of the hydraulic principle structure of the double-acting ultra-high pressure hydraulic pump of the present invention.

[0047] In the figure: 1. Oil tank; 2. Handle frame; 3. Motor; 4. Output valve block; 5. Electric control box; 6. Heat sink; 7. Cooling fan; 8. Oil plug cover; 9. Pressure gauge; 10. Pressure regulating valve; 11. Two-position two-way solenoid valve; 12. Hydraulic control valve block; 13. Two-position four-way solenoid valve; 14. Filter; 15. First low-pressure plunger pair; 16. Second low-pressure plunger pair; 17. Ultra-high-pressure plunger pair; 18. 6MPa unloading valve; 19. 12MPa unloading valve; 20. Hydraulic control one-way valve; 21. Throttle valve; 22. Hydraulic control stop valve; 23. Low-pressure working oil ports (two); 24. High-pressure working oil ports (two). DETAILED DESCRIPTION

[0048] The present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0049] Figure 1-5 Shown is a multi-angle structural schematic diagram and a pipeline structure principle diagram of a specific example of the double-acting ultra-high-pressure hydraulic pump described in the present invention. In this example, the double-acting ultra-high-pressure hydraulic pump includes an oil tank 1, a handle frame 2 and a motor 3, wherein the oil tank 1 is a container for storing hydraulic oil; the handle frame 2 is fixedly installed on the top of the oil tank 1 by screws, and can directly or indirectly connect the parts on the hydraulic pump, thereby forming a whole; the motor 3 is arranged in the inner cavity of the handle frame 2, and the lower end of the output shaft of the motor 3 extends to the inner cavity of the oil tank 1 and is connected to the pump body valve group.

[0050] An output valve block 4 and a hydraulic control valve block 12 are provided on the top of the oil tank 1 in front of the motor 3 .

[0051] Two high-pressure working oil ports are arranged side by side on the side of the output valve block 4 (sealed by bolts in the figure); a pressure gauge 9 is provided on the top of the output valve block 4 for detecting the pressure of the oil output from the high-pressure working oil port of the output valve block 4 and for the convenience of observation by workers. A two-position two-way solenoid valve 11 is provided on the right side of the pressure gauge 9, and a pressure regulating valve 10 is provided behind the two-position two-way solenoid valve 11 for manually adjusting the pressure; a high-pressure oil inlet, a low-pressure oil inlet, a hydraulically controlled oil inlet, an oil return inlet, and an oil return outlet are provided at the bottom of the output valve block 4; a hydraulically controlled one-way valve 20, a throttle valve 21, and a hydraulically controlled stop valve 22 are provided inside the output valve block 4.

[0052] The interior of the output valve block 4 is provided with a first channel connecting the high-pressure oil inlet and the high-pressure working oil port, a first one-way valve is provided in the first channel, and a second channel connecting the low-pressure oil inlet and the first channel is provided, and the connection point between the second channel and the first channel is located between the first one-way valve and the high-pressure oil inlet, and a second one-way valve is provided in the second channel; a third channel connecting the high-pressure working oil port and the return oil outlet is provided, and a hydraulically controlled one-way valve 20, a throttle valve 21, and a hydraulically controlled stop valve 22 are arranged in the third channel, wherein the throttle valve 21 and the hydraulically controlled stop valve 22 are connected in series and in parallel with the hydraulically controlled one-way valve 20.

[0053] There are also channels connecting the low-pressure oil inlet and the oil inlet of the two-position two-way solenoid valve and the hydraulic control port of the hydraulic stop valve, a channel connecting the return oil outlet and the oil outlet of the two-position two-way solenoid valve and the return oil inlet, a channel connecting the hydraulic control oil inlet and the hydraulic control port of the hydraulic control one-way valve, and a channel connecting the first channel and the measuring port of the pressure gauge 9.

[0054] The inlet of the throttle valve and the inlet of the hydraulically controlled one-way valve are respectively communicated with the high-pressure working oil port inside the valve block, the outlet of the throttle valve is connected to the inlet of the hydraulically controlled stop valve, and the outlet of the hydraulically controlled one-way valve and the outlet of the hydraulically controlled stop valve are respectively communicated with the return oil outlet of the output valve block inside the valve block.

[0055] Two low-pressure working oil ports are provided on the side of the hydraulic control valve block 12 (the quick connector shown in the figure is installed on the low-pressure working oil port); a two-position four-way solenoid valve 13 is provided on the top of the hydraulic control valve block 12; and a low-pressure oil inlet, a low-pressure oil outlet, an oil return outlet, and a hydraulic control oil outlet are provided at the bottom of the hydraulic control valve block 12.

[0056] The interior of the hydraulic control valve block 12 is respectively provided with a channel connecting the low-pressure oil inlet and the oil inlet of the two-position four-way solenoid valve 13, a channel connecting the first working oil port of the two-position four-way solenoid valve 13 and the low-pressure oil outlet, a channel connecting the oil return port and the oil return outlet of the two-position four-way solenoid valve 13, and a channel connecting the second working oil port of the two-position four-way solenoid valve 13 and the two low-pressure working oil ports and the hydraulic control oil outlet.

[0057] The low-pressure oil inlet of the output valve block is connected to the low-pressure oil outlet of the hydraulic control valve block through an oil pipe. The hydraulic control oil inlet of the output valve block is connected to the hydraulic control oil outlet of the hydraulic control valve block through an oil pipe. The oil return inlet of the output valve block is connected to the oil return outlet of the hydraulic control valve block through an oil pipe. The oil return outlet of the output valve block is connected to the inner cavity of the oil tank.

[0058] The pump body valve group is provided with a high-pressure oil circuit and a low-pressure oil circuit, and a one-way valve and an unloading valve are provided on one side of the low-pressure oil circuit. The high-pressure oil circuit and the low-pressure oil circuit are connected to the high-pressure oil inlet of the output valve block 4 and the low-pressure oil inlet of the hydraulic control valve block 12 respectively through oil pipes.

[0059] A filter is arranged around the connection between the bottom end of the motor 3 and the pump body valve group, and the filter is arranged in the inner cavity of the oil tank 1, which is beneficial to the motor 3 to filter the hydraulic oil when working, and prevents impurities and particles entrained in the hydraulic oil from entering the pump body valve group, thereby affecting the normal operation of the pump body valve group or greatly shortening the service life of the pump body valve group.

[0060] An electric control box 5 is provided behind the motor 3 and is fixedly connected to one side of the handle frame 2. The electric control box 5 digitally controls the switching action of the two-position two-way solenoid valve 12 and the two-position four-way solenoid valve 13, so that the hydraulic pump switches between high-pressure output and low-pressure output, realizing a double-acting function with stable performance.

[0061] A heat sink 6 is fixedly provided on one side of the motor 3, and a heat dissipation fan 7 is fixedly provided on one side of the outer wall of the heat sink 6, and the heat dissipation fan 7 is fixedly connected to one side of the handle frame 2 through a connecting rod, so that the heat dissipation fan 7 absorbs the heat generated by the operation of the motor 3 during operation, thereby avoiding the device from being in a high temperature environment for a long time, thereby improving the working time of the device.

[0062] In addition, an oil plug cover 8 is provided at the bottom end of the front side of the fuel tank 1, and one end of the oil plug cover 8 passes through a side wall of the fuel tank 1 and extends to the inner cavity of the fuel tank 1, which is conducive to injecting gasoline into the fuel tank 1 through the oil plug cover 8, thereby ensuring that the oil stored in the fuel tank 1 can be used for the normal operation of the device.

[0063] When using the double-acting hydraulic pump of the present invention to drive the double-acting hydraulic tensioner, connect the high-pressure working oil port of the hydraulic pump to the positive working oil port of the tensioner, and connect the low-pressure working oil port of the hydraulic pump to the reset working oil port of the tensioner. Figure 5 , the working process of the hydraulic pump is as follows:

[0064] When the hydraulic tensioner needs to work in the forward direction, the double-acting ultra-high pressure hydraulic pump two-position four-way solenoid valve 13 and the two-position two-way solenoid valve 11 are operated in the right position, and the system realizes the high-pressure output working state in which the pressure oil is output from the high-pressure working oil port 24 and the oil is returned from the low-pressure working oil port 23. When the system pressure is lower than the set pressure of the unloading valve 18, the first low-pressure plunger pair 15, the second low-pressure plunger pair 16 and the ultra-high pressure plunger pair 17 work at the same time to output pressure oil. When the system pressure is higher than the unloading valve 18 and lower than the set pressure of the unloading valve 19, the pressure of the first low-pressure plunger pair 15, the second low-pressure plunger pair 16 and the ultra-high pressure plunger pair 17 work at the same time to output pressure oil. When the pressure is applied, the oil output by the first low-pressure plunger pair 15 is unloaded and returned through the unloading valve 18, and then the second low-pressure plunger 16 and the ultra-high-pressure plunger 17 work together to output the pressure oil. When the system pressure is higher than the set pressure of the unloading valve 19, the oil output by the second low-pressure plunger pair is unloaded and returned through the unloading valve 19, and then the ultra-high-pressure plunger pair 17 outputs the pressure oil alone, thereby realizing the conversion of the system output from low pressure and high flow to high pressure and small flow, and then reaching an ultra-high pressure of more than 100MP at the fastest speed;

[0065] When the hydraulic tensioner needs to be reset, first switch the two-position two-way solenoid valve 11 to the left position, and the two-position two-way solenoid valve 11 cuts off the connection between the first working oil port A of the two-position four-way solenoid valve 13 and the return oil pipeline. The oil pressure output from the first working oil port A of the two-position four-way solenoid valve 13 controls the hydraulic control stop valve 22 to be connected, and the oil with ultra-high pressure in the high-pressure working oil port is unloaded under the throttle state through the throttle valve 21 and the hydraulic control stop valve 22, and the pressure in the high-pressure working oil port drops rapidly. Then, the two-position four-way solenoid valve 13 switches to the left position and is output from the second working oil port B. The low-pressure oil output from the second working oil port B of the two-position four-way solenoid valve 13 is output through the low-pressure working oil port, enters the hydraulic tensioner cylinder and starts to drive the hydraulic tensioner to reset. At the same time, the hydraulically controlled one-way valve is connected and the hydraulically controlled stop valve is closed (at the same time, because the first working oil port of the two-position four-way solenoid valve is connected to the return oil port of the two-position four-way solenoid valve, the hydraulic end pressure of the hydraulically controlled stop valve disappears), and the oil in the high-pressure working oil port that has been unloaded returns quickly through the hydraulically controlled one-way valve with a large flow rate.

[0066] In the above process, when the ultra-high-pressure oil starts to return, it is first throttled and unloaded through the throttle valve and the hydraulically controlled stop valve. After the ultra-high pressure is released, the oil is quickly returned through the hydraulically controlled one-way valve with a large flow rate, which effectively avoids the ultra-high-pressure oil instantly rushing into the return oil pipeline and causing impact on the return oil pipeline and the low-pressure components connected to it.

Claims

1. A double-acting ultra-high-pressure hydraulic pump suitable for a double-acting hydraulic tensioner, comprising a fuel tank, an ultra-high-pressure plunger pair, a low-pressure plunger pair, a high-pressure working oil port, a low-pressure working oil port, and a two-position four-way solenoid valve; The oil outlet of the ultra-high-pressure plunger pair is unidirectionally connected to the high-pressure working oil port through the high-pressure output pipeline, and the high-pressure working oil port is unidirectionally connected to the oil tank through the return oil pipeline; the oil outlet of the low-pressure plunger pair is connected to the oil inlet of the two-position four-way solenoid valve, the first working oil port of the two-position four-way solenoid valve is unidirectionally connected to the high-pressure output pipeline, the second working oil port of the two-position four-way solenoid valve is connected to the low-pressure working oil port, and the return oil port of the two-position four-way solenoid valve is connected to the return oil pipeline located downstream of the hydraulic control stop valve; It is characterized in that It also includes a two-position two-way solenoid valve, and a throttle valve, the hydraulically controlled stop valve, and a hydraulically controlled one-way valve are provided at the inlet end of the return oil pipeline. The throttle valve and the hydraulically controlled stop valve are connected in series and in parallel with the hydraulically controlled one-way valve. The hydraulic control port of the hydraulically controlled stop valve is connected to the first working oil port of the two-position four-way solenoid valve, the hydraulic control port of the hydraulically controlled one-way valve is connected to the second working oil port of the two-position four-way solenoid valve, the oil inlet of the two-position two-way solenoid valve is connected to the first working oil port of the two-position four-way solenoid valve, and the oil outlet of the two-position two-way solenoid valve is connected to the return oil pipeline downstream of the hydraulically controlled stop valve. The oil pressure output by the first working oil port of the two-position four-way solenoid valve can control the conduction of the hydraulically controlled stop valve.

2. The double-acting ultra-high pressure hydraulic pump according to claim 1, characterized in that: A handle frame is provided on the top of the oil tank, and a pump body valve group is provided in the oil tank, and the pump body valve group includes the low-pressure plunger pair, the ultra-high-pressure plunger pair, a low-pressure oil outlet, a high-pressure oil outlet, a low-pressure unloading valve, and a low-pressure oil return port; The oil outlet of the low-pressure plunger pair is communicated with the low-pressure oil outlet of the pump body valve group, and the oil outlet of the ultra-high-pressure plunger pair is communicated with the high-pressure oil outlet of the pump body valve group. The low-pressure unloading valve is arranged between the low-pressure oil outlet and the low-pressure oil return port of the pump body valve group, and the low-pressure oil return port of the pump body valve group is connected to the inner cavity of the oil tank; An output valve group, an electric control box, a motor, a heat sink and a cooling fan are arranged inside the handle frame. The motor is fixedly arranged on the top of the fuel tank. The lower end of the motor output shaft passes through the fuel tank top cover and extends to the inner cavity of the fuel tank. A cam for driving the low-pressure plunger pair and the ultra-high-pressure plunger pair is installed at the lower end of the motor output shaft.

3. The double-acting ultra-high pressure hydraulic pump according to claim 2, characterized in that: The output valve group includes a hydraulic control valve block, the two-position four-way solenoid valve, an output valve block, and the two-position two-way solenoid valve; The hydraulic control valve block is fixedly arranged on the top of the oil tank, and the two-position four-way solenoid valve is arranged on the hydraulic control valve block. The hydraulic control valve block is provided with a low-pressure oil inlet, a low-pressure oil outlet, the low-pressure working oil port, an oil return outlet, and a hydraulic control oil outlet; the oil inlet, oil return port, and first working oil port of the two-position four-way solenoid valve are respectively communicated with the low-pressure oil inlet, oil return outlet, and low-pressure oil outlet on the hydraulic control valve block through the inside of the valve block; the second working oil port of the two-position four-way solenoid valve is simultaneously communicated with the low-pressure working oil port and the hydraulic control oil outlet on the hydraulic control valve block through the inside of the valve block; the low-pressure oil inlet of the hydraulic control valve block is connected to the low-pressure oil outlet of the pump body valve group through an oil pipe.

4. The double-acting ultra-high pressure hydraulic pump according to claim 3, characterized in that: The output valve block is fixedly arranged on the top of the oil tank, the two-position two-way solenoid valve is arranged on the output valve block, the output valve block is provided with a low-pressure oil inlet, a high-pressure oil inlet, a hydraulically controlled oil inlet, a return oil inlet, a return oil outlet, and the high-pressure working oil port, and the output valve block is provided with the throttle valve, the hydraulically controlled stop valve, and the hydraulically controlled one-way valve; The high-pressure oil inlet of the output valve block is connected to the high-pressure oil outlet of the pump body valve group through an oil pipe; The high-pressure oil inlet of the output valve block is in one-way communication with the high-pressure working oil port through a one-way valve inside the valve block, and the low-pressure oil inlet of the output valve block is in one-way communication with the high-pressure oil inlet of the output valve block through a one-way valve inside the valve block; The inlet of the throttle valve and the inlet of the hydraulically controlled one-way valve are respectively connected to the high-pressure working oil port inside the valve block, the outlet of the throttle valve is connected to the inlet of the hydraulically controlled stop valve, and the outlet of the hydraulically controlled one-way valve and the outlet of the hydraulically controlled stop valve are respectively connected to the return oil outlet of the output valve block inside the valve block; The hydraulic control port of the hydraulically controlled stop valve is communicated with the low-pressure oil inlet of the output valve block inside the valve block, the oil inlet of the two-position two-way solenoid valve is communicated with the low-pressure oil inlet of the output valve block through the inside of the valve block, the hydraulic control port of the hydraulically controlled check valve is communicated with the hydraulic control oil inlet of the output valve block inside the valve block, and the oil outlet of the two-position two-way solenoid valve is communicated with the return oil outlet of the output valve block through the inside of the valve block; The low-pressure oil inlet of the output valve block is connected to the low-pressure oil outlet of the hydraulic control valve block through an oil pipe, the hydraulic control oil inlet of the output valve block is connected to the hydraulic control oil outlet of the hydraulic control valve block, the return oil inlet of the output valve block is connected to the return oil outlet of the hydraulic control valve block, the return oil inlet of the output valve block is connected to the return oil outlet of the hydraulic control valve block, the return oil inlet of the output valve block is connected to the return oil outlet of the output valve block inside the valve block, and the return oil outlet of the output valve block is connected to the inner cavity of the oil tank.

5. The double-acting ultra-high pressure hydraulic pump according to claim 2, characterized in that: The heat sink is fixedly arranged on one side of the motor, the cooling fan is fixedly arranged on one side of the outer wall of the heat sink, and the cooling fan is fixedly connected to one side of the handle frame through a connecting rod; the electric control box is arranged on the rear side of the motor, and the electric control box is fixedly arranged on the handle frame.

6. The double-acting ultra-high pressure hydraulic pump according to claim 4, characterized in that: A pressure gauge is fixedly installed on the top of the output valve block, and the oil inlet of the pressure gauge is connected to the high-pressure working oil port of the output valve block. A pressure regulating valve is provided on the right side of the output valve block, and the inlet of the pressure regulating valve is connected to the high-pressure oil inlet of the output valve block.

7. The double-acting ultra-high pressure hydraulic pump according to claim 1, characterized in that: An oil plug cover is provided at the bottom end of the front face of the oil tank, and one end of the oil plug cover penetrates a side wall of the oil tank and extends to the inner cavity of the oil tank.

8. The double-acting ultra-high pressure hydraulic pump according to claim 2, characterized in that: A filter is arranged around the connection between the bottom end of the motor and the pump body valve group, and the filter is arranged in the inner cavity of the oil tank.

Images