Oil pump system, hydraulic system, and working machine

Abstract

The utility model relates to the field of hydraulic pressure, and discloses an oil pump system, a hydraulic system and an operation machine. The main pump is driven by the rotating shaft and is provided with a main oil suction port and a main oil discharge port; the booster pump can be driven by the rotating shaft and is provided with a booster oil suction port and a booster oil discharge port; the oil path assembly comprises a main oil suction path connected with the main oil suction port and a pressurizing oil discharge path connected with the pressurizing oil discharge port and the main oil suction path; and the clutch is arranged between the rotating shaft and the booster pump and can connect or disconnect the rotating shaft and the booster pump. The overall energy efficiency of the oil pump system with the booster pump under the low-speed working condition can be greatly improved, heating of the oil pump system is reduced, the phenomenon that the oil pump system causes cavitation and noise abnormity under the high-speed working condition can be avoided, and therefore the oil pump system has excellent performance under the different rotating speed working conditions.

Description

Technical Field

[0001] The present application belongs to the field of hydraulic technology, and specifically relates to an oil pump system, a hydraulic system and an operating machine. Background Art

[0002] In hydraulic systems, by reducing the oil pump displacement and increasing the oil pump speed, the size of the oil pump can be effectively reduced, making it more suitable for various host systems with compact layouts. At the same time, the rapid development of electrification has promoted the application of high-speed motors, and high-speed oil pumps adapted to high-speed motors have gained broader application prospects.

[0003] Taking the hydraulic piston pump as an example, the main factor limiting its speed increase is its self-priming performance. Usually, the inlet pressure of the piston pump oil needs to be higher than the air separation pressure of the oil to avoid cavitation. When the speed of the self-priming piston pump is too high and the flow demand is large, the pressure difference between the oil pump inlet pressure and the atmospheric pressure increases, and it is easy to drop below the air separation pressure, causing cavitation. Therefore, ordinary piston pumps limit the maximum speed to avoid cavitation and ensure the life of the oil pump.

[0004] In order to increase the speed of the oil pump and avoid cavitation caused by the oil pressure entering the plunger pump being lower than the air separation pressure, a booster pump is currently used to increase the inlet pressure of the plunger pump to achieve the purpose of increasing the speed of the oil pump. However, when the existing oil pump system that increases the inlet pressure of the plunger pump through a booster pump is operated under low pressure and low speed conditions, the oil pump system not only has extremely low overall efficiency, but also has the problem of high heat generation, resulting in extremely low overall energy efficiency of the oil pump system and adversely affecting its service life. Utility Model Content

[0005] The purpose of the present application is to provide an oil pump system, a hydraulic system and an operating machine, which can greatly improve the overall energy efficiency of the oil pump system with a booster pump under low-speed conditions and reduce its heat generation, and can avoid cavitation and abnormal noise caused by the oil pump system under high-speed conditions.

[0006] In order to achieve the above objectives, the present application provides an oil pump system, which includes:

[0007] Rotating shaft;

[0008] A main pump, driven by the rotating shaft and provided with a main oil suction port and a main oil discharge port;

[0009] A booster pump, which can be driven by the rotating shaft and is provided with a booster oil suction port and a booster oil discharge port;

[0010] An oil circuit assembly, comprising a main oil suction circuit connected to the main oil suction port and a boost oil discharge circuit connected to the boost oil discharge port and the main oil suction circuit; and

[0011] The clutch is disposed between the rotating shaft and the boost pump and is capable of engaging or disengaging the rotating shaft and the boost pump.

[0012] In some embodiments, the oil circuit assembly further includes an anti-cavitation valve serially connected in the boost oil drain oil circuit and having a first opening pressure;

[0013] When the oil pressure in the boost and drain oil circuit is less than the first opening pressure, the anti-cavitation valve is in a cut-off state; when the oil pressure in the boost and drain oil circuit is not less than the first opening pressure, the anti-cavitation valve is in a conducting state.

[0014] In some embodiments, the oil circuit assembly further includes a check valve connected in series in the main oil suction circuit, and a cut-off end of the check valve is connected to the pressurized oil discharge circuit.

[0015] In some embodiments, the oil circuit assembly further includes a boost oil suction circuit connected to the boost oil suction port, and the boost oil suction circuit is connected to the conducting end of the check valve.

[0016] In some embodiments, the oil circuit assembly further includes a boost pressure control valve having an adjustable second opening pressure, and one end of the boost pressure control valve is respectively connected to the boost oil drain circuit and the main oil suction port.

[0017] In some embodiments, the clutch is disposed between the main pump and the boost pump.

[0018] In some embodiments, the clutch includes an input hub, an output hub and a plurality of elastic throw block mechanisms, the input hub is fixedly sleeved on the rotating shaft, and the plurality of elastic throw block mechanisms are arranged in sequence along the circumferential direction on the outer periphery of the input hub, the output hub is sleeved outside the input hub at intervals and is connected to the boost pump, and the inner circumferential wall of the output hub is provided with a plurality of clamping grooves arranged in sequence along the circumferential direction, each of the elastic throw block mechanisms includes a centrifugal throw block and an elastic bending part whose two ends are respectively connected to the centrifugal throw block and the input hub; under low-speed conditions, the centrifugal throw block is separated from the clamping groove; under high-speed conditions, the centrifugal throw block can overcome the elastic force of the elastic bending part under the action of centrifugal force and move to clamp into the clamping groove.

[0019] In some embodiments, the rotating shaft includes a power shaft and a transmission shaft, the main pump is further provided with a main oil distribution plate and a pump suction mechanism, the main oil suction port and the main oil discharge port are both arranged on the main oil distribution plate, the booster pump is further provided with a booster oil distribution plate and a rotor, the booster oil suction port and the booster oil discharge port are both arranged on the booster oil distribution plate;

[0020] Wherein, the transmission shaft and the pumping mechanism are both hinged to the power shaft, the booster oil distribution plate, the rotor, the main oil distribution plate and the pumping mechanism are arranged in sequence along the axial direction on the transmission shaft, and the clutch is arranged between the transmission shaft and the rotor.

[0021] In some embodiments, the main oil distribution plate is in end-face contact with the rotor, an oil distribution groove is formed on the end surface of the main oil distribution plate facing the rotor, and the oil distribution groove is communicated with an internal oil passage of the boost pump.

[0022] The second aspect of the present application also provides a hydraulic system, which includes:

[0023] tank;

[0024] powerplant; and

[0025] In the above-mentioned oil pump system, the boost oil suction port and the main oil suction port are both connected to the oil tank, and the rotating shaft is driven by the power device.

[0026] The third aspect of the present application also provides a working machine, which includes the above-mentioned hydraulic system.

[0027] Through the above technical scheme, the oil pump system of the present application can adjust the state of the clutch according to different speed conditions. For example, when the shaft drives the main pump to run at a low speed, the flow demand of the main pump is small, and the pressure difference between the inlet oil pressure of the main pump and the atmospheric pressure is small. Therefore, the inlet oil pressure will not be lower than the air separation pressure to cause cavitation and abnormal noise. Therefore, under low-speed conditions, the shaft can be separated from the boost pump by the clutch, and the boost pump does not need to be pressurized, so as to avoid the boost pump running all the time and causing drive energy waste and dragging down the overall efficiency of the oil pump system under low-speed conditions, and reduce the mechanical loss and hydraulic overflow loss of the boost pump, thereby improving the overall energy efficiency of the oil pump system under low-speed conditions, reducing its heat and extending its service life. For another example, when the shaft drives the main pump to run at high speed, the clutch can be used to connect the shaft to the booster pump, so that the shaft drives the main pump and the booster pump to run synchronously. At this time, the oil in the oil pump system is pressurized by the booster pump and then enters the main pump from the booster oil discharge oil circuit and the main suction port, effectively avoiding cavitation and abnormal noise caused by the inlet oil pressure of the main pump being lower than the air separation pressure. In general, the present application enables the oil pump system to have excellent performance under different speed conditions.

[0028] Other features and advantages of the embodiments of the present application will be described in detail in the subsequent detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] The accompanying drawings are used to provide a further understanding of the embodiments of the present application and constitute a part of the specification. Together with the following specific embodiments, they are used to explain the embodiments of the present application, but do not constitute a limitation on the embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without creative work. In the drawings:

[0030] Figure 1 A schematic diagram of a hydraulic system in a specific implementation manner of the present application;

[0031] Figure 2 A schematic diagram of an oil pump system in a specific implementation manner of the present application;

[0032] Figure 3 It is a schematic diagram of a clutch in a specific implementation manner of the present application.

[0033] Description of Reference Numerals

[0034] 10 Main pump 20 Clutch

[0035] 30 Booster pump 40 Anti-cavitation valve

[0036] 50 Check valve 60 Fuel tank

[0037] 70 Boost pressure control valve 80 Valve group

[0038] 90 Power shaft 100 Transmission shaft

[0039] 110 front pump housing 120 rear pump housing

[0040] 130 Oil seal 140 Bearing

[0041] 150 Power unit 160 Universal joint

[0042] 101 plunger 102 cylinder

[0043] 103 Main oil distribution plate 201 Input hub

[0044] 202 output hub 203 centrifugal throw

[0045] 204 elastic bending part 301 rotor

[0046] 302 booster oil distribution plate DETAILED DESCRIPTION

[0047] The specific implementation of the present application is described in detail below in conjunction with the accompanying drawings. It should be understood that the specific implementation described here is only used to illustrate and explain the present application, and is not used to limit the present application.

[0048] Reference Figures 1 to 3 The first exemplary embodiment of the present application provides an oil pump system capable of adaptive supercharging, more specifically, capable of adaptive supercharging based on speed, which includes a rotating shaft, a main pump 10, a boost pump 30, an oil circuit assembly and a clutch 20.

[0049] Specifically, when the rotating shaft inputs power from the outside of the oil pump system, the rotating shaft drives the main pump 10 to operate, and can drive the boost pump 30 to operate. When the main pump 10 is in operation, it can suck oil through its main oil suction port, pressurize the oil in the pump, and then pump the pressure oil outward through its main oil discharge port (such as pumping it to the hydraulic actuator to drive its operation). When the boost pump 30 is in operation, it can suck oil from the outside of the oil pump system through its boost oil suction port, pressurize the oil in the pump, and then pump the boost oil to the main oil suction port of the main pump 10 through its boost oil discharge port, so as to increase the inlet oil pressure of the main pump 10.

[0050] In addition, the main pump 10 of the present application has more than one oil suction path. In the oil circuit assembly, there are provided a main oil suction oil circuit connected to the main oil suction port and a boost oil discharge oil circuit connected to the boost oil discharge port and the main oil suction oil circuit, so that the main oil suction port can not only suck oil from the outside of the oil pump system through the oil inlet end of the main oil suction oil circuit, but also suck the boost oil after the boost oil is merged into the main oil suction oil circuit through the boost oil discharge oil circuit.

[0051] The clutch 20 provided in the present application can enable the main pump 10 to switch between the two oil suction paths. The clutch 20 is provided between the rotating shaft and the boost pump 30 and can engage or disengage the rotating shaft and the boost pump 30 .

[0052] When the clutch 20 engages the rotating shaft and the boost pump 30, the rotating shaft drives the main pump 10 and the boost pump 30 to operate synchronously. At this time, the boost pump 30 can collect the boost oil into the main suction oil circuit through the boost oil discharge circuit, and then the boost oil is passed into the main pump 10 through the main suction oil circuit.

[0053] When the clutch 20 separates the rotating shaft and the boost pump 30, the rotating shaft drives the main pump 10 to operate, and the boost pump 30 stops operating due to lack of power input. At this time, the main pump 10 sucks oil from the outside of the oil pump system through the oil inlet end of the main oil suction circuit, and the boost pump 30 does not perform a boosting function.

[0054] Based on the above settings, the oil pump system of the present application can adjust the state of the clutch 20 according to different speed conditions. For example, when the shaft drives the main pump 10 to run at a low speed, the flow demand of the main pump 10 is relatively small, and the pressure difference between the inlet oil pressure of the main pump 10 and the atmospheric pressure is relatively small. Therefore, the inlet oil pressure will not be lower than the air separation pressure to cause cavitation and abnormal noise. Therefore, under low-speed conditions, the shaft can be separated from the boost pump 30 through the clutch 20, and the boost pump 30 does not need to be pressurized, so as to avoid the boost pump 30 running all the time and causing drive energy waste and dragging down the overall efficiency of the oil pump system under low-speed conditions (the total efficiency of the existing oil pump system is the product of the efficiencies of the main pump and the boost pump in series, and the existing boost pump is extremely inefficient under low-speed conditions, resulting in the overall efficiency of the oil pump system under low-speed conditions. The mechanical loss and hydraulic overflow loss of the boost pump 30 are reduced, thereby improving the overall energy efficiency of the oil pump system under low-speed conditions, reducing its heat generation, and extending its service life.

[0055] For another example, when the shaft drives the main pump 10 to run at high speed, the clutch 20 can be used to engage the shaft with the boost pump 30, so that the shaft drives the main pump 10 and the boost pump 30 to run synchronously. At this time, the oil in the oil pump system is pressurized by the boost pump 30 and then enters the main pump from the boost oil discharge circuit and the main suction port, effectively preventing the inlet oil pressure of the main pump 10 from being lower than the air separation pressure, causing cavitation and abnormal noise.

[0056] In general, the present application enables the oil pump system to have excellent performance under different speed conditions.

[0057] It should be noted that the present application does not limit the oil pump system to engage the clutch 20 under high-speed conditions and disengage the clutch 20 under low-speed conditions, but the state of the clutch 20 can be switched timely based on actual working conditions.

[0058] In some embodiments, the critical points of high and low speed conditions (i.e., preset critical speeds) can be preset in advance, and the structural form, parameters, control timing, etc. of the clutch 20 can be designed based on this premise, so that under low speed conditions where the rotation speed of the shaft is less than the preset critical speed, the clutch 20 separates the shaft and the boost pump 30, so that the main pump 10 only absorbs oil through the main suction oil circuit, and under high speed conditions where the rotation speed of the shaft is not less than the preset critical speed, the clutch 20 engages the shaft and the boost pump 30, so that the main pump 10 absorbs oil through the boost pump 30.

[0059] In other words, by designing the structural form and parameters of the clutch 20, or adopting linkage control of the controller and the speed sensor, the clutch 20 can have the function of switching the engagement and disengagement states according to the speed, so that the oil pump system can accurately and flexibly switch the operating mode according to the speed.

[0060] More specifically, for example, when the clutch 20 needs to be controlled by linkage control of the controller and the speed sensor, the speed sensor can be used to detect the speed of the rotating shaft in real time and transmit the data to the controller. The controller has a preset critical speed value preset by humans and can compare the speed of the rotating shaft with the preset critical speed value. When the controller determines that the speed of the rotating shaft is less than the preset critical speed, the controller controls the clutch 20 to disengage; when the controller determines that the speed of the rotating shaft is not less than the preset critical speed, the controller controls the clutch 20 to engage.

[0061] The example of adjusting the preset critical speed by adjusting the structure and parameters of the clutch 20 will be described later in conjunction with Figure 3 The introduction will not be elaborated here.

[0062] In some embodiments, reference Figure 2 The oil circuit assembly further includes a valve group 80. The valve group 80 in the figure is for illustration only and does not mean that the valve structure shown is the specific structure of the anti-cavitation valve 40 or the check valve 50 and the boost pressure control valve 70 to be described later. In addition, the anti-cavitation valve 40 and the check valve 50 and the boost pressure control valve 70 to be described later do not have to be integrated into the form of the valve group 80, and can also be provided separately, and the present application does not limit this.

[0063] The valve group 80 may include an anti-cavitation valve 40 connected in series in the boost and discharge oil circuit and having a first opening pressure. In the case where the oil pressure in the boost and discharge oil circuit is less than the first opening pressure, the anti-cavitation valve 40 is in a cut-off state, and the boost pump 30 will not input the boost oil whose oil pressure does not meet the minimum requirement (i.e., the oil pressure value equal to the first opening pressure) into the main pump 10. In the case where the oil pressure in the boost and discharge oil circuit is not less than the first opening pressure, the anti-cavitation valve 40 is in a conducting state, and the boost pump 30 can input the boost oil whose oil pressure meets the minimum requirement into the main pump 10, thereby boosting the inlet oil pressure of the main pump 10.

[0064] By providing the anti-cavitation valve 40, it can be ensured that the boost pump 30 will not input the boost oil whose oil pressure does not meet the minimum requirement into the main pump 10, thereby more effectively avoiding the main pump 1 from sucking in air and causing cavitation and abnormal noise, and further improving the anti-cavitation capability of the oil pump system.

[0065] It should be noted that the present application does not limit the specific selection of the anti-cavitation valve 40. For example, Figure 1 The spring check valve shown, or the relief valve, sequence valve, etc., can be selected according to the actual working conditions.

[0066] In some embodiments, the valve group 80 may include a check valve 50 connected in series in the main oil suction circuit, and the cut-off end of the check valve 50 is connected to the boost oil discharge circuit. When the clutch 20 is engaged and the boost pump 30 collects the boost oil into the main oil suction circuit through the boost oil discharge circuit, the boost oil collected in the main oil suction circuit will apply a closing force to the cut-off end of the check valve 50, ensuring that the check valve 50 cannot be opened at this time, so that the check valve 50 can prevent the boost oil collected in the main oil suction circuit from flowing out from the oil inlet end of the main oil suction circuit in the reverse direction, avoiding the loss of the inlet oil pressure of the main pump 10, and then ensuring that the inlet oil pressure is not lower than the air separation pressure, further reducing the risk of cavitation and abnormal noise.

[0067] Furthermore, the oil circuit assembly also includes a boost oil suction circuit connected to the boost oil suction port, and the boost oil suction circuit is connected to the conducting end of the check valve 50. In this way, the oil pump system can only suck oil through the oil inlet end of the main oil suction circuit. When the boost pump 30 is not running, the oil sucked from the oil inlet end of the main oil suction circuit will enter the main pump 10 through the check valve 50. When the boost pump 30 is running, the oil sucked from the oil inlet end of the main oil suction circuit enters the boost pump 30 through the boost oil suction circuit. At this time, the oil supply structure outside the oil pump system (such as an oil tank) only needs to open an oil port connected to the oil inlet end of the main oil suction circuit, so that the main pump 10 and the boost pump 30 can be supplied with oil.

[0068] It should be noted that the present application does not limit the specific selection of the check valve 50. For example, Figure 1 The single check valve shown may also be a sequence valve or other valves that can be used as a check valve. Different types can be selected according to actual working conditions.

[0069] In some embodiments, the valve group 80 may include a boost pressure control valve 70 provided with an adjustable second opening pressure, one end of which is connected to the boost oil discharge circuit and the main oil suction port of the main pump 10. When the boost pump 30 is running, after the boost oil in the boost oil discharge circuit is merged into the main oil suction circuit, if the inlet pressure of the main pump 10 is less than the second opening pressure of the boost pressure control valve 70, the inlet pressure may continue to rise; if the inlet pressure of the main pump 10 is not less than the second opening pressure, the boost pressure control valve 70 opens to release the pressure, so that by setting the boost pressure control valve 70, the inlet pressure of the main pump 10 can be maintained equal to the second opening pressure, and since the second opening pressure is adjustable, it means that the inlet pressure of the main pump 10 can also be adjusted, so that the main pump 10 can timely and accurately adjust its inlet pressure according to the actual working conditions to adapt to more different working conditions.

[0070] In contrast, the oil discharge port of the booster pump in the prior art is directly connected to the oil suction port of the main pump. Since the booster pump mostly adopts an impeller centrifugal pump, when the oil discharge pressure of the impeller centrifugal pump reaches the upper limit, it cannot continue to rise. This oil pressure upper limit is determined by the impeller structure of the impeller centrifugal pump. During the use and matching process, it cannot be flexibly adjusted according to the boost pressure demand of the main pump, so it is easy to cause the boost pressure to be too high or too low, resulting in energy loss or insufficient boost pressure. The oil pump system of the present application can flexibly adjust the boost pressure by setting a boost pressure control valve 70 to adapt to different main pump characteristics and operating conditions, thereby improving the overall efficiency of the oil pump system.

[0071] It should be noted that the present application does not limit the specific selection of the boost pressure control valve 70. For example, Figure 1 The spring check valve with adjustable opening pressure shown, or the overflow valve, sequence valve, etc., can be selected according to the actual working conditions.

[0072] In addition, the valve group 80 of the present application is not limited to including at least one of the anti-cavitation valve 40, the check valve 50 and the boost pressure control valve 70 described above, and valves with other functions can also be integrated according to actual working conditions. By adopting the form of the valve group 80, the integration is high, it is easy to disassemble and assemble, and it is compact, which is conducive to reducing the overall volume of the oil pump system.

[0073] In some embodiments, reference Figure 2 The clutch 20 can be arranged between the main pump 10 and the boost pump 30, making the structural arrangement of the oil pump system more compact.

[0074] Further, refer to Figure 3 The clutch 20 may include an input hub 201, an output hub 202, and a plurality of elastic block mechanisms. Specifically, the input hub 201 is fixedly sleeved on the rotating shaft, and a plurality of elastic block mechanisms are arranged in sequence along the circumferential direction on the outer periphery of the input hub 201 at intervals, the output hub 202 is sleeved outside the input hub 201 at intervals and connected to the boost pump 30, and the inner peripheral wall of the output hub 202 is provided with a plurality of clamping grooves arranged in sequence along the circumferential direction, and each elastic block mechanism includes a centrifugal block 203 that can be clamped in the clamping groove and an elastic bending member 204 whose two ends respectively connect the centrifugal block 203 and the input hub 201.

[0075] When the rotating shaft is stationary, the input hub 201 is also stationary accordingly. At this time, the multiple elastic block mechanisms will not move, and the input hub 201 and the output hub 202 are not connected.

[0076] When the shaft rotates at a low speed, the input hub 201 also rotates at a low speed accordingly. At this time, the centrifugal block 203 is subjected to a smaller centrifugal force and is thrown outward a smaller distance. The expansion amount of the bending angle of the elastic bending part 204 is small, and the centrifugal block 203 cannot be clamped in the clamping groove of the inner wall of the output hub 202. Therefore, the input hub 201 and the output hub 202 still cannot form a connection, so that the clutch 20 cannot transmit the power of the shaft to the boost pump 30, so that the boost pump 30 does not operate under low-speed conditions.

[0077] When the shaft rotates at high speed, the input hub 201 also rotates at high speed accordingly. At this time, the centrifugal block 203 is subjected to a large centrifugal force and is thrown outward a large distance. The bending angle of the elastic bending part 204 is greatly expanded. The centrifugal block 203 can be clamped in the clamping groove of the inner wall of the output hub 202, so that the input hub 201 and the output hub 202 are relatively fixed, so that the output hub 202 rotates synchronously with the high-speed rotation of the shaft. Since the output hub 202 is connected to the boost pump 30, the clutch 20 can transmit the power of the shaft to the boost pump 30, so that the boost pump 30 can operate under high-speed conditions.

[0078] When the rotation speed of the rotating shaft slows down, the centrifugal force on the centrifugal block 203 becomes smaller. At this time, the elastic bending part 204 can drive the centrifugal block 203 to disengage from the clamping groove of the inner wall of the output hub 202 under the action of the elastic restoring force, thereby disconnecting the input hub 201 and the output hub 202, making it impossible for the clutch 20 to transmit the power of the rotating shaft to the boost pump 30, that is, the boost pump 30 stops running.

[0079] It should be noted that when it is necessary to adjust the value of the preset critical speed, the preset critical speed can be adjusted by using an elastic bending part 204 with a different elastic modulus, an elastic bending part 204 with a different shape, or a centrifugal throw block 203 with a different weight (i.e., adjusting the structural shape and parameters of the clutch 20).

[0080] In some embodiments, reference Figure 2 The rotating shaft includes a power shaft 90 and a transmission shaft 100, and the transmission shaft 100 is hinged to the power shaft 90 (for example, the transmission shaft 100 and the power shaft 90 can be hinged through a universal joint 160). The power shaft can input power from the outside of the oil pump system and drive the transmission shaft 100 to rotate.

[0081] The main pump 10 is also provided with a main oil distribution plate 103 and a pumping mechanism, which is hinged to the power shaft 90, and the main oil suction port and the main oil discharge port are both provided on the main oil distribution plate 103. After the oil enters the main oil suction port on the main oil distribution plate 103, the main oil distribution plate 103 can distribute the oil to the pumping mechanism, and the pumping mechanism can discharge the pressure oil inside through the main oil discharge port on the main oil distribution plate 103.

[0082] by Figure 2For example, the main pump 10 can adopt a self-priming plunger pump (and the figure adopts a bevel axis plunger pump), and the pumping mechanism includes a plunger 101 and a cylinder 102. Among them, one end of the plunger 101 is hinged to the inner end of the power shaft 90 through a ball joint, and the other end of the plunger 101 can slide into the cylinder 102. When the power shaft 90 rotates, it can drive the plunger 101 and the cylinder 102 to rotate synchronously. At the same time, the plunger 101 will slide back and forth in the cylinder 102, so that the oil can be continuously pumped.

[0083] The boost pump 30 is also provided with a boost oil distribution plate 302 and a rotor 301, and the boost oil suction port and the boost oil discharge port are both provided on the boost oil distribution plate 302. After the oil enters the boost oil suction port on the boost oil distribution plate 302, the boost oil distribution plate 302 can distribute the oil to the pump body of the boost pump 30 (the pump body includes the rotor 301), and the pump body of the boost pump 30 can discharge the boost oil inside it through the boost oil discharge port of the boost oil distribution plate 302, and then the boost oil is transported to the main suction port on the main oil distribution plate 103 through the boost oil discharge oil circuit and the main oil suction oil circuit, so as to boost the inlet oil pressure of the main pump 10.

[0084] In addition, the boost oil distribution plate 302, the rotor 301, the main oil distribution plate 103 and the pumping mechanism in this embodiment are arranged in sequence along the axial direction on the transmission shaft 100, so that the oil pump system has a compact structure, providing a structural basis for the integrated design of the oil pump system as an integrated and smaller-sized tandem oil pump.

[0085] Furthermore, the clutch 20 is disposed between the transmission shaft 100 and the rotor 301. When the clutch 20 is in an engaged state, the power of the transmission shaft 100 can be transmitted to the rotor 301, thereby driving the boost pump 30 to operate. When the clutch 20 is in a disengaged state, the power of the transmission shaft 100 cannot be transmitted to the rotor 301, and the boost pump 30 stops operating. It can be seen that the arrangement of the clutch 20 in this embodiment is also conducive to realizing a compact and integrated design of the oil pump system.

[0086] Furthermore, the main oil distribution plate 103 is in end face contact with the rotor 301, and an oil distribution groove is formed on the end face of the main oil distribution plate 103 facing the rotor 301, and the oil distribution groove is connected to the internal oil channel of the boosting pump 30, so that the main oil distribution plate 103 can be used to distribute the internal oil of the boosting pump 30 and the main pump 10 at the same time, making one plate for multiple uses, making the structure of the oil pump system more compact.

[0087] In some embodiments, continue to refer to Figure 2The oil pump system may further include a housing (for example, may include the front pump housing 110 and the rear pump housing 120 shown in the figure). By arranging the above-mentioned rotating shaft, main pump 10, boost pump 30, oil circuit assembly and clutch 20 in the housing, the oil pump system can be integrated into an integrated and smaller-sized tandem oil pump, which is convenient for quick installation and use in different hydraulic systems.

[0088] In addition, the above-mentioned tandem oil pump may also be provided with components such as an oil seal 130 and a bearing 140 to ensure the sealing performance of the oil pump and the rotational support for the power shaft 90 .

[0089] In some embodiments, the boost pump 30 may adopt a vane pump, for example, a double-acting vane pump, whose volumetric efficiency can be as high as over 95%. When the boost pump 30 is used in series with the main pump 10, since the total efficiency of the oil pump system is the product of the efficiencies of the boost pump 30 and the main pump 10, the present application adopts a vane pump. Compared with the existing impeller centrifugal pump with a maximum volumetric efficiency of only about 53%, the boosting efficiency of the boost pump 30 can be greatly improved, heat generation can be reduced, thereby greatly improving the overall efficiency of the oil pump system and reducing energy loss and waste.

[0090] It should be noted that the main pump 10 of the present application is not limited to the plunger pump exemplified above, and the booster pump 30 is not limited to the vane pump exemplified above, but the main pump 10 and the booster pump 30 can use any type of oil pump according to actual working conditions. In other words, the present application does not limit the specific selection of the main pump 10 and the booster pump 30.

[0091] Refer to Figure 1 The second exemplary embodiment of the present application also provides a hydraulic system, which includes an oil tank 60, a power device 150 (such as a high-speed motor, etc.) and the above-mentioned oil pump system. Among them, the boost oil suction port and the main oil suction port of the oil pump system are both connected to the oil tank 60, and the rotating shaft is driven by the power device 150. Obviously, the hydraulic system of the present application should have all the technical effects brought by the above-mentioned oil pump system, so it will not be repeated here.

[0092] In addition, the third exemplary embodiment of the present application further provides a working machine, which includes the above-mentioned hydraulic system. Obviously, the working machine of the present application should also have all the technical effects brought by the above-mentioned oil pump system, so it will not be repeated here.

[0093] The operating machinery of the present application includes but is not limited to engineering machinery, agricultural machinery or operating robots, etc. The power of the operating machinery can be new energy batteries, fuel engines, hybrid devices or mechanisms, etc.

[0094] In addition, the operating machinery of the present application can be a new energy vehicle, such as a new energy vehicle, a truck crane, a truck crane, a mixer truck, a pump truck, a fire truck, a road construction vehicle, a sanitation vehicle, etc., and can provide power to the hydraulic system through a power battery (such as a lithium battery, a hydrogen fuel cell), for example, providing power to the power device 150 in the aforementioned hydraulic system.

[0095] In the description of the present application, it should be understood that the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of the present application, "plurality" means at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0096] In this application, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, an electrical connection, or communication with each other; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0097] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0098] Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limitations on the present application. Ordinary technicians in this field can change, modify, replace and modify the above embodiments within the scope of the present application.

Claims

1. Oil pump system, characterized in that: include: Rotating shaft; A main pump (10), driven by the rotating shaft and provided with a main oil suction port and a main oil discharge port; A booster pump (30), which can be driven by the rotating shaft and is provided with a booster oil suction port and a booster oil discharge port; An oil circuit assembly, comprising a main oil suction circuit connected to the main oil suction port and a boost oil discharge circuit connected to the boost oil discharge port and the main oil suction circuit; and The clutch (20) is arranged between the rotating shaft and the boosting pump (30) and is capable of engaging or disengaging the rotating shaft and the boosting pump (30).

2. The oil pump system according to claim 1, characterized in that: The oil circuit assembly also includes an anti-cavitation valve (40) which is serially connected in the pressurized oil discharge circuit and is provided with a first opening pressure; Under the condition that the oil pressure of the boost oil discharge oil circuit is less than the first opening pressure, the anti-cavitation valve (40) is in a shutoff state; Under the operating condition that the oil pressure in the boost oil discharge circuit is not less than the first opening pressure, the anti-cavitation valve (40) is in a conducting state.

3. The oil pump system according to claim 1, characterized in that: The oil circuit assembly further comprises a check valve (50) connected in series in the main oil suction circuit, and a cut-off end of the check valve (50) is connected to the pressurized oil discharge circuit.

4. The oil pump system according to claim 3, characterized in that: The oil circuit assembly also includes a boost oil suction circuit connected to the boost oil suction port, and the boost oil suction circuit is connected to the conducting end of the check valve (50).

5. The oil pump system according to claim 1, characterized in that: The oil circuit assembly also includes a boost pressure control valve (70) provided with an adjustable second opening pressure, and one end of the boost pressure control valve (70) is respectively connected to the boost oil discharge circuit and the main oil suction port.

6. The oil pump system according to claim 1, characterized in that: The clutch (20) is arranged between the main pump (10) and the boost pump (30).

7. The oil pump system according to claim 6, characterized in that: The clutch (20) comprises an input hub (201), an output hub (202) and a plurality of elastic block mechanisms, wherein the input hub (201) is fixedly sleeved on the rotating shaft, and the plurality of elastic block mechanisms are arranged in sequence along the circumferential direction on the outer peripheral edge of the input hub (201), and the output hub (202) is sleeved outside the input hub (201) at intervals and connected to the boost pump (30), and the inner peripheral wall of the output hub (202) is provided with a plurality of clamping grooves arranged in sequence along the circumferential direction, and each of the elastic block mechanisms comprises a centrifugal block (203) and an elastic bending part (204) whose two ends are respectively connected to the centrifugal block (203) and the input hub (201); under low-speed working conditions, the centrifugal block (203) is separated from the clamping groove; Under high-speed working conditions, the centrifugal throw block (203) can overcome the elastic force of the elastic bending part (204) under the action of centrifugal force and move outward to be engaged with the engaging groove.

8. The oil pump system according to claim 1, characterized in that: The rotating shaft comprises a power shaft (90) and a transmission shaft (100); the main pump (10) is further provided with a main oil distribution plate (103) and a pump suction mechanism; the main oil suction port and the main oil discharge port are both arranged on the main oil distribution plate (103); the booster pump (30) is further provided with a booster oil distribution plate (302) and a rotor (301); the booster oil suction port and the booster oil discharge port are both arranged on the booster oil distribution plate (302); The transmission shaft (100) and the pumping mechanism are both hinged to the power shaft (90); the booster oil distribution plate (302), the rotor (301), the main oil distribution plate (103) and the pumping mechanism are sequentially arranged along the axial direction on the transmission shaft (100); and the clutch (20) is arranged between the transmission shaft (100) and the rotor (301).

9. The oil pump system according to claim 8, characterized in that: The main oil distribution plate (103) and the rotor (301) are in end-face contact, and an oil distribution groove is formed on the end face of the main oil distribution plate (103) facing the rotor (301), and the oil distribution groove is in communication with an internal oil passage of the boost pump (30).

10. Hydraulic system, characterized in that, include: Fuel tank (60); Power plant (150); and According to the oil pump system according to any one of claims 1 to 9, the boost oil suction port and the main oil suction port are both connected to the oil tank (60), and the rotating shaft is driven by the power device (150).

11. An operating machine, characterized in that: Comprising a hydraulic system according to claim 10.

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