Hydraulic oil replenishment system and engineering machine

Abstract

This invention discloses a hydraulic oil replenishment system and engineering machinery, relating to the field of hydraulic technology. The hydraulic oil replenishment system includes: a power module, the outlet of which is connected to the system to be replenished; a flow regulation module, the inlet of which is connected to the outlet of the power module; a accumulator delay device, the inlet of which is connected to the outlet of the flow regulation module, and the outlet of which is connected to a return oil tank; a differential pressure relief valve, the main pressure inlet of which is connected to the outlet of the power module, and the overflow port of which is connected to the return oil tank; and the control terminal of which is connected to the inlet of the accumulator delay device. The hydraulic oil replenishment system provided by this invention can provide low-pressure hydraulic oil to the system to be replenished during the power start-up phase, avoiding full-load starting of the starter motor and effectively solving the problem of difficult starting of power equipment in special environments.

Description

Technical Field

[0001] This invention relates to the field of hydraulic technology, and more specifically, to a hydraulic oil replenishment system. Furthermore, this invention also relates to engineering machinery incorporating the aforementioned hydraulic oil replenishment system. Background Technology

[0002] In the prior art, the principle of a hydraulic closed system is as follows: Figure 1 As shown, the system consists of a closed-loop pump 01, an oil replenishment unit 02, a closed-loop motor 03, and a flushing valve 04. The oil replenishment unit 02 is used to fill the working chambers of the closed-loop pump 01 and the closed-loop motor 03 with external cooling oil, replenishing leaked working oil and replacing hot oil inside the system to prevent high temperatures inside the closed-loop system. The oil replenishment unit 02 includes a power module and an oil replenishment pressure valve. The power module and the oil replenishment pressure regulating valve can be integrated into the closed-loop pump 01. Considering cost and structural layout, the power module is often a fixed-displacement pump with a displacement of about 18% to 25% of the maximum displacement of the closed-loop pump 01. The oil replenishment pressure valve is used to limit the maximum pressure of the oil replenishment system, with a pressure value of about 2.5 MPa. However, since the oil replenishment unit 02 uses a fixed-displacement pump and a fixed-displacement pressure valve, the load power caused by the oil replenishment unit 02 during power start-up cannot be avoided, often causing the starter motor to start at near full load. When the battery is slightly depleted, power starting difficulties often occur.

[0003] In summary, how to solve the problem of starting power equipment in special environments is a problem that urgently needs to be solved by those skilled in the art. Summary of the Invention

[0004] In view of this, the purpose of the present invention is to provide a hydraulic oil replenishment system that can replenish low-pressure hydraulic oil to the system to be replenished during the startup phase of power equipment, thereby facilitating the startup of power equipment.

[0005] Another object of the present invention is to provide an engineering machine including the above-described hydraulic oil replenishment system.

[0006] To achieve the above objectives, the present invention provides the following technical solution:

[0007] A hydraulic oil replenishment system, comprising:

[0008] The power module is used to draw hydraulic oil from the oil tank, and its outlet is connected to the system to be replenished with oil.

[0009] A flow regulation module, wherein the oil inlet of the flow regulation module is connected to the oil outlet of the power module;

[0010] A liquid storage delay device, wherein the oil inlet of the liquid storage delay device is connected to the oil outlet of the flow regulation module, and the oil outlet of the liquid storage delay device is connected to the return oil tank;

[0011] A differential pressure relief valve is provided, wherein the main pressure inlet of the differential pressure relief valve is connected to the oil outlet of the power module, and the overflow port of the differential pressure relief valve is connected to the return oil tank; the control end of the differential pressure relief valve is connected to the oil inlet of the accumulator delay device.

[0012] Optionally, the flow regulation module includes a throttle valve and a check valve. The oil inlet of the throttle valve is connected to the oil outlet of the power module, the oil outlet of the throttle valve is connected to the oil inlet of the check valve, and the oil outlet of the check valve is connected to the oil inlet of the liquid storage delay device.

[0013] Optionally, the power module includes a replenishing pump, the outlet of which is connected to the inlet of the throttle valve and the main pressure inlet of the differential pressure relief valve.

[0014] Optionally, the control end of the differential pressure relief valve is provided with a pressure spring. When the liquid storage delay device has not completed liquid storage, the pressure at the main pressure inlet of the differential pressure relief valve is the ratio of the elastic force F of the pressure spring to the second working area A2 of the main pressure inlet.

[0015] Optionally, the first working area A1 of the control end of the differential pressure relief valve is smaller than the second working area A2 of the main pressure inlet of the differential pressure relief valve.

[0016] Optionally, it also includes a hydraulically controlled check valve, the oil inlet of which is connected to the oil inlet of the liquid storage delay device, the oil outlet of which is connected to the return oil tank, and the control end of which is connected to the oil outlet of the power module.

[0017] When the pressure at the control end of the hydraulic check valve is greater than or equal to the preset pressure, the hydraulic check valve is in the closed state. When the pressure at the control end of the hydraulic check valve is less than the preset pressure, the hydraulic check valve is in the open state, so that the oil in the reservoir flows out to the return oil tank.

[0018] An engineering machine, comprising the hydraulic oil replenishment system described in any one of the above claims.

[0019] When using the hydraulic oil replenishment system provided by this invention, when the equipment is in the power start-up stage, the hydraulic oil output by the power module enters the accumulator delay unit through the flow regulation module. During this process, the oil inlet of the accumulator delay unit is basically pressureless and the differential pressure relief valve is not subjected to pressure. Part of the hydraulic oil flowing out of the power module flows back to the return oil tank through the differential pressure relief valve, and the other part of the hydraulic oil flowing out of the power module replenishes the oil to be replenished at a low pressure P1 = F / A2.

[0020] After the accumulator has finished accumulating fluid, no hydraulic oil flows through the flow regulation module. The pressure at the control end of the differential pressure relief valve is the pressure at the inlet end of the accumulator, and the pressure at the inlet end of the accumulator is the pressure at the outlet of the power module. The oil pressure at the main pressure inlet 44 of the differential pressure relief valve is the oil pressure at the inlet end of the on / off control module, P2 = F / (A2-A1), which is higher than the oil pressure during the power start-up phase. In addition, the hydraulic oil flowing out from the power module replenishes the oil to the system that needs to be replenished at high pressure P2.

[0021] Compared with existing technologies, the hydraulic oil replenishment system provided by this invention can provide low-pressure hydraulic oil to the system to be replenished during the power start-up phase, avoiding full-load start-up of the starter motor and effectively solving the problem of difficult start-up of power equipment in special environments; after start-up is completed, it can provide high-pressure hydraulic oil to the system to be replenished so that the equipment can work normally.

[0022] In addition, the present invention also provides an engineering machine including the above-mentioned hydraulic oil replenishment system. Attached Figure Description

[0023] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0024] Figure 1 This is a schematic diagram of the principle of a hydraulic closed system in the prior art;

[0025] Figure 2 A schematic diagram of a specific embodiment of the hydraulic oil replenishment system provided by the present invention;

[0026] Figure 3 This is a schematic diagram of a differential pressure relief valve.

[0027] Figure 1 middle:

[0028] 01 is a closed-loop pump, 02 is an oil replenishment unit, 03 is a closed-loop motor, and 04 is a flushing valve;

[0029] Figure 2 , 3 middle:

[0030] 1 is the oil replenishment pump, 2 is the hydraulic check valve, 3 is the liquid storage delay device, 4 is the differential pressure relief valve, 41 is the pressure spring, 42 is the control terminal, 43 is the overflow port, 44 is the main pressure inlet, 5 is the throttle valve, and 6 is the check valve. Detailed Implementation

[0031] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0032] The core of this invention is to provide a hydraulic oil replenishment system that can replenish low-pressure hydraulic oil to the system requiring oil replenishment during the startup phase of power equipment, thereby facilitating the startup of the power equipment.

[0033] Another core aspect of this invention is to provide an engineering machine that includes the aforementioned hydraulic oil replenishment system.

[0034] Please refer to Figure 2 or Figure 3 .

[0035] This specific embodiment discloses a hydraulic oil replenishment system, including: a power module for drawing hydraulic oil from an oil tank, the outlet of which is connected to the system to be replenished; a flow regulation module, the inlet of which is connected to the outlet of the power module; a accumulator delay unit 3, the inlet of which is connected to the outlet of the flow regulation module, and the outlet of which is connected to the return oil tank; a differential pressure relief valve 4, the main pressure inlet 44 of which is connected to the outlet of the power module, and the overflow port 43 of which is connected to the return oil tank; and a control terminal 42 of which is connected to the inlet of the accumulator delay unit 3.

[0036] In this specific embodiment, the flow regulation module is used to regulate the flow rate of hydraulic oil flowing into the on / off control module. After adjustment, its flow rate is constant and is not affected by the pressure changes at both ends of the flow regulation module. Part of the hydraulic oil flowing out of the replenishing pump 1 flows through the flow regulation module, thus preventing all the hydraulic oil flowing out of the replenishing pump 1 from flowing through the flow regulation module.

[0037] In this specific embodiment, the power module may include a replenishing pump 1, the outlet of which is connected to the inlet of the throttle valve 5 and the main pressure inlet 44 of the differential pressure relief valve 4.

[0038] When using the hydraulic oil replenishment system provided in this specific embodiment, when the equipment is in the power start-up stage, the hydraulic oil output by the power module enters the accumulator delay 3 through the flow regulation module. During this process, the oil inlet of the accumulator delay 3 is basically pressureless on the differential pressure relief valve 4. Part of the hydraulic oil flowing out of the power module flows back to the return oil tank through the differential pressure relief valve 4. The other part of the hydraulic oil flowing out of the power module replenishes the oil to be replenished at a low pressure P1 = F / A2. Here, F is the elastic force F of the pressure spring 41 in the differential pressure relief valve 4.

[0039] After the accumulator delay 3 has finished accumulating fluid, no hydraulic oil flows through the flow regulation module. The pressure at the control end 42 of the differential pressure relief valve 4 is the pressure at the oil inlet of the accumulator delay 3, and the pressure at the oil inlet of the accumulator delay 3 is the pressure at the oil outlet of the power module. The oil pressure at the main pressure inlet 44 of the differential pressure relief valve 4 is the oil pressure at the oil inlet of the on / off control module, P2 = F / (A2-A1), which is higher than the oil pressure during the power start-up phase. In addition, the hydraulic oil flowing out from the power module replenishes the oil to the system that needs to be replenished at high pressure P2.

[0040] Compared to existing technologies, the hydraulic oil replenishment system provided in this specific embodiment can provide low-pressure hydraulic oil to the system to be replenished during the power start-up phase, avoiding full-load start-up of the starter motor and effectively solving the problem of difficult start-up of power equipment in special environments; after start-up is completed, it can provide high-pressure hydraulic oil to the system to be replenished so that the equipment can work normally.

[0041] In one specific embodiment, such as Figure 2 As shown, the flow regulation module includes a throttle valve 5 and a check valve 6. The oil inlet of the throttle valve 5 is connected to the oil outlet of the power module, the oil outlet of the throttle valve 5 is connected to the oil inlet of the check valve 6, and the oil outlet of the check valve 6 is connected to the oil inlet of the accumulator delay unit 3.

[0042] In practical use, when the power module stops working, the hydraulic oil in the accumulator delay 3 flows out from the inlet end, and the check valve 6 can prevent the hydraulic oil in the accumulator delay 3 from flowing back to the replenishing pump 1; at the same time, during normal oil replenishment, the hydraulic oil at the outlet of the replenishing pump 1 can flow into the accumulator delay 3 through the throttle valve 5 and the check valve 6.

[0043] In one specific embodiment, the control end 42 of the differential pressure relief valve 4 is equipped with a pressure spring 41. When the liquid storage delay device 3 has not completed liquid storage, the pressure at the main pressure inlet 44 of the differential pressure relief valve 4 is the ratio of the elastic force F of the pressure spring 41 to the second working area A2 of the main pressure inlet 44. The first working area A1 of the control end 42 of the differential pressure relief valve 4 is smaller than the second working area A2 of the main pressure inlet 44 of the differential pressure relief valve 4.

[0044] like Figure 3As shown, the control end 42 of the differential pressure relief valve 4 is equipped with a pressure spring 41. The first working area A1 of the control end 42 of the differential pressure relief valve 4 is smaller than the second working area A2 of the main pressure inlet 44 of the differential pressure relief valve 4. An overflow port 43 is provided in the middle of the differential pressure relief valve 4. The force of the pressure spring 41 is F. The first working area of ​​the control end 42 of the differential pressure relief valve 4 is A1. The second working area of ​​the main pressure inlet 44 of the differential pressure relief valve 4 is A2, and A2 is greater than A1. The pressure area difference is ΔA, and ΔA = A2 - A1. The compensation differential pressure is ΔP. ​​The oil replenishment lubrication pressure during the power start-up stage, which is the hydraulic oil pressure replenished by the power module to the system to be replenished, is P1. P1 is approximately equal to ΔP. After the equipment starts up, the power module replenishes high-pressure hydraulic oil to the system to be replenished. The pressure of the high-pressure hydraulic oil is P2, and P2 = F / ΔA.

[0045] Based on the above embodiments, such as Figure 2 As shown, the hydraulic oil replenishment system also includes a hydraulically controlled check valve 2. The inlet end of the hydraulically controlled check valve 2 is connected to the inlet end of the accumulator delay unit 3, the outlet end of the hydraulically controlled check valve 2 is connected to the return oil tank, and the control end of the hydraulically controlled check valve 2 is connected to the outlet of the power module. When the pressure at the control end of the hydraulically controlled check valve 2 is greater than or equal to the preset pressure, the hydraulically controlled check valve 2 is in the closed state. When the pressure at the control end of the hydraulically controlled check valve 2 is less than the preset pressure, the hydraulically controlled check valve 2 is in the open state, so that the oil in the accumulator delay unit 3 flows out to the return oil tank.

[0046] During actual use, in the power start-up phase, the pressure at the outlet of the replenishing pump 1 acts on the hydraulic control check valve 2. At this time, the pressure at the outlet of the replenishing pump 1 is greater than or equal to the preset pressure, causing the hydraulic control check valve 2 to be in the closed state. The hydraulic oil output by the replenishing pump 1 flows into the accumulator delay unit 3 through the throttle valve 5 and the check valve 6. The inlet of the accumulator delay unit 3 has virtually no pressure acting on the control end 42 of the differential pressure relief valve 4. The hydraulic oil pressure at the main pressure inlet 44 of the differential pressure relief valve 4 is similar to that at the first... The product of the two working areas A2 is approximately equal to the force F of the pressure spring 41, i.e., P1 = ΔP = F / A2. Here, P1 is the pressure at which the power module replenishes low-pressure hydraulic oil to the system to be replenished. During the power start-up phase, the flow rate after the throttle valve 5 and the differential pressure relief valve 4 form a speed control valve is Q, the filling volume in the accumulator delay 3 is V, and the filling time is V / Q. In order to ensure that the system to be replenished is continuously replenished with low-pressure P1 during the power start-up phase, V / Q can be made greater than the power start-up time.

[0047] When the accumulator delay unit 3 has finished accumulating fluid, the pressure at the outlet of the replenishing pump 1 acts on the hydraulic control check valve 2. At this time, the pressure at the outlet of the replenishing pump 1 is greater than or equal to the preset pressure, so that the hydraulic control check valve 2 is in the closed state, and no hydraulic oil flows through the throttle valve 5. The pressure at the inlet of the accumulator delay unit 3 is the same as the pressure at the outlet of the replenishing pump 1, which is P2. Combined with the specific structure of the differential pressure relief valve 4, when the valve core inside the differential pressure relief valve 4 is in a balanced state, P2*A1+F=P2*A2. Therefore, P2=F / ΔA. Here, P2 is the pressure of the power module replenishing high-pressure hydraulic oil to the system to be replenished.

[0048] When the power module stops working, the oil replenishment pump 1 stops rotating, and the oil outlet of the oil replenishment pump 1 is depressurized. The pressure at the oil outlet of the oil replenishment pump 1 acts on the hydraulic control check valve 2. At this time, the pressure at the oil outlet of the oil replenishment pump 1 is less than the preset pressure, so that the hydraulic control check valve 2 is in the conducting state. The accumulator delay unit 3 is equipped with a soft spring. Under the elastic force of the soft spring, the hydraulic oil in the accumulator delay unit 3 is discharged to the return oil tank through the hydraulic control check valve 2 until the hydraulic oil in the accumulator delay unit 3 is emptied, in preparation for the next pressure reduction start-up of the equipment.

[0049] In this specific embodiment, the preset pressure can be zero pressure or other values ​​that meet the requirements. The specific value will be determined according to the actual situation and will not be elaborated here.

[0050] In addition to the hydraulic oil replenishment system described above, the present invention also provides an engineering machine that includes the hydraulic oil replenishment system disclosed in the above embodiments. For the structure of other parts of the engineering machine, please refer to the prior art, which will not be repeated here.

[0051] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on its differences from other embodiments. Similar or identical parts between embodiments can be referred to interchangeably. Any combination of all embodiments provided by this invention is within the scope of protection of this invention and will not be elaborated upon here.

[0052] The hydraulic oil replenishment system and engineering machinery provided by this invention have been described in detail above. Specific examples have been used to illustrate the principles and implementation methods of this invention. The descriptions of the embodiments above are only for the purpose of helping to understand the method and core ideas of this invention. It should be noted that those skilled in the art can make several improvements and modifications to this invention without departing from the principles of this invention, and these improvements and modifications also fall within the protection scope of the claims of this invention.

Claims

1. A hydraulic oil replenishment system, characterized in that, include: The power module is used to draw hydraulic oil from the oil tank, and its outlet is connected to the system to be replenished with oil. A flow regulation module, wherein the oil inlet of the flow regulation module is connected to the oil outlet of the power module; The oil storage delay device (3) has its inlet end connected to the outlet end of the flow regulation module, and its outlet end connected to the return oil tank. Differential pressure relief valve (4), the main pressure inlet (44) of the differential pressure relief valve (4) is connected to the oil outlet of the power module, and the overflow port (43) of the differential pressure relief valve (4) is connected to the return oil tank; the control end (42) of the differential pressure relief valve (4) is connected to the oil inlet of the liquid storage delay device (3).

2. The hydraulic oil replenishment system according to claim 1, characterized in that, The flow regulation module includes a throttle valve (5) and a check valve (6). The oil inlet of the throttle valve (5) is connected to the oil outlet of the power module, the oil outlet of the throttle valve (5) is connected to the oil inlet of the check valve (6), and the oil outlet of the check valve (6) is connected to the oil inlet of the liquid storage delay device (3).

3. The hydraulic oil replenishment system according to claim 2, characterized in that, The power module includes a replenishing pump (1), the outlet of which is connected to the inlet of the throttle valve (5) and the main pressure inlet (44) of the differential pressure relief valve (4).

4. The hydraulic oil replenishment system according to claim 1, characterized in that, The control end (42) of the differential pressure relief valve (4) is equipped with a pressure spring (41). When the liquid storage delay device (3) has not completed liquid storage, the pressure of the main pressure inlet (44) of the differential pressure relief valve (4) is the ratio of the elastic force of the pressure spring (41) to the second working area A2 of the main pressure inlet (44).

5. The hydraulic oil replenishment system according to claim 4, characterized in that, The first working area A1 of the control end (42) of the differential pressure relief valve (4) is smaller than the second working area A2 of the main pressure inlet (44) of the differential pressure relief valve (4).

6. The hydraulic oil replenishment system according to any one of claims 1-5, characterized in that, It also includes a hydraulic control check valve (2), the oil inlet of which is connected to the oil inlet of the liquid storage delay device (3), the oil outlet of which is connected to the return oil tank, and the control end of which is connected to the oil outlet of the power module. When the pressure at the control end of the hydraulic check valve (2) is greater than or equal to the preset pressure, the hydraulic check valve (2) is in the closed state. When the pressure at the control end of the hydraulic check valve (2) is less than the preset pressure, the hydraulic check valve (2) is in the open state, so that the oil in the liquid storage delay device (3) flows out to the return oil tank.

7. An engineering machinery, characterized in that, Includes the hydraulic oil replenishment system as described in any one of claims 1-6.

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