Hydraulic control system and engineering machinery

Abstract

The utility model belongs to the technical field of hydraulic systems, and discloses a hydraulic control system and engineering machinery, the hydraulic control system comprises an oil tank, an oil pump, a reversing valve, a first hydraulic motor, a second hydraulic motor and an oil supplementing piece, the oil tank is communicated with an oil inlet of the reversing valve through the oil pump, and a working oil port A1 of the reversing valve is communicated with an oil port B1 of the first hydraulic motor; an oil port B2 of the first hydraulic motor communicates with an oil port C1 of the second hydraulic motor through a first communicating pipe, an oil port C2 of the second hydraulic motor communicates with a working oil port A2 of the reversing valve through a third communicating pipe, and the oil supplementing part is used for conveying hydraulic oil to the first communicating pipe or conveying the hydraulic oil of the first communicating pipe to the third communicating pipe; the engineering machinery comprises the hydraulic control system. The hydraulic control system provided by the utility model is used for engineering machinery and can avoid air suction or pressure building of an oil way caused by inconsistent rotating speeds of the two hydraulic motors during turning, so that the problem of differential speed is solved.

Description

Technical Field

[0001] The utility model relates to the technical field of hydraulic systems, in particular to a hydraulic control system and engineering machinery. Background Art

[0002] The hydraulic control system with dual hydraulic motors in the prior art refers to Figure 1 As shown, in the system, the first hydraulic motor 4' and the second hydraulic motor 5' are arranged in series. The first hydraulic motor 4' and the second hydraulic motor 5' respectively drive the left front wheel and the right front wheel of the engineering machinery to rotate. Specifically, when the engineering machinery is moving forward, the left position of the reversing valve 3' is in the working position, the oil pump 2' is working, and the hydraulic oil in the oil tank 1' is first delivered to the first hydraulic motor 4' through the reversing valve 3', and then delivered to the second hydraulic motor 5' through the series pipeline, and then the hydraulic oil is output through the reversing valve 3' and finally returns to the oil tank 1'; when the engineering machinery is moving backward, the right position of the reversing valve 3' is in the working position, the oil pump 2' is working, and the hydraulic oil in the oil tank 1' is first delivered to the second hydraulic motor 5' through the reversing valve 3', and then delivered to the first hydraulic motor 4' through the series pipeline, and then the hydraulic oil is output through the reversing valve 3' and finally returns to the oil tank 1'.

[0003] In the above-mentioned hydraulic control system, when the engineering machinery turns left and moves forward, the turning radius of the left front wheel is small, the speed of the first hydraulic motor 4' is slow, the turning radius of the right front wheel is large, and the speed of the second hydraulic motor 5' is fast. Because the two hydraulic motors are not equipped with a differential, the second hydraulic motor 5' sucks out the hydraulic oil in the series oil pipe between the two hydraulic motors; and when the engineering machinery turns left and moves backward, the turning radius of the left front wheel is small, the speed of the first hydraulic motor 4' is slow, the turning radius of the right front wheel is large, and the speed of the second hydraulic motor 5' is fast. The hydraulic oil entering from the second hydraulic motor 5' gathers in the series oil pipe between the two hydraulic motors, causing the pressure of the hydraulic oil in the series oil pipe to increase, that is, pressure build-up occurs, causing the pressure of the entire system to increase and energy consumption to increase. Utility Model Content

[0004] The purpose of the utility model is to provide a hydraulic control system and engineering machinery, which can add oil to the pipeline between the two hydraulic motors by arranging an oil replenishing part, thereby avoiding the problem of oil circuit suction or pressure holding caused by inconsistent rotation speeds of the two hydraulic motors when the engineering machinery turns, thereby solving the differential problem.

[0005] To achieve this purpose, the utility model adopts the following technical solutions:

[0006] A hydraulic control system includes an oil tank, an oil pump, a reversing valve, a first hydraulic motor, a second hydraulic motor and an oil replenishing member; wherein:

[0007] The oil inlet of the oil pump is connected to the oil tank, the oil outlet of the oil pump is connected to the oil inlet of the reversing valve, the oil outlet of the reversing valve is connected to the oil tank, the working oil port A1 of the reversing valve is connected to the oil port B1 of the first hydraulic motor, the oil port B2 of the first hydraulic motor is connected to the oil port C1 of the second hydraulic motor through a first connecting pipe, and the oil port C2 of the second hydraulic motor is connected to the working oil port A2 of the reversing valve through a third connecting pipe;

[0008] The oil replenishing member is connected to the first communicating pipe and the third communicating pipe, and is used to deliver hydraulic oil to the first communicating pipe, or to deliver the hydraulic oil in the first communicating pipe to the third communicating pipe.

[0009] Preferably, the oil replenishing component includes a shuttle valve, the oil port D1 of the shuttle valve is connected to the connecting pipeline between the working oil port A1 of the reversing valve and the oil port B1 of the first hydraulic motor, the oil port D2 of the shuttle valve is connected to the third connecting pipe, and the oil port D3 of the shuttle valve is connected to the first connecting pipe.

[0010] Preferably, the oil replenishing component further includes a throttling component, the oil port D3 of the shuttle valve is connected to the first connecting pipe through a second connecting pipe, and the throttling component is arranged on the second connecting pipe.

[0011] Preferably, the throttling element is configured as a throttle valve.

[0012] Preferably, a driving motor is also included, and the driving motor is connected to the oil pump and is used to drive the oil pump to work.

[0013] Preferably, an overflow valve is further included, wherein the oil inlet of the overflow valve is connected to the connecting pipeline between the oil pump and the oil inlet of the reversing valve, and the oil outlet of the overflow valve is connected to the oil tank.

[0014] Preferably, the oil outlet of the overflow valve and the oil outlet of the reversing valve converge into an oil return pipe, and the oil return pipe is connected to the oil tank.

[0015] Preferably, the reversing valve is configured as a three-position four-way electromagnetic reversing valve.

[0016] Preferably, a filtering device is further included, and the filtering device is arranged on the connecting pipeline between the oil tank and the oil inlet of the oil pump.

[0017] An engineering machine comprises a chassis and also comprises any one of the hydraulic control systems described above; wherein:

[0018] The chassis is provided with a left front wheel and a right front wheel;

[0019] The first hydraulic motor is connected to the left front wheel and is used to drive the left front wheel to rotate;

[0020] The second hydraulic motor is connected to the right front wheel and is used to drive the right front wheel to rotate.

[0021] Beneficial effects:

[0022] When the hydraulic control system provided by the utility model is applied to engineering machinery, when the engineering machinery turns left and moves forward, the turning radius of the left front wheel is small and the rotation speed of the first hydraulic motor is slow, while the turning radius of the right front wheel is large and the rotation speed of the second hydraulic motor is fast. There will be a tendency for the second hydraulic motor to suck out the hydraulic oil in the first connecting pipe. At this time, the oil replenishing component intervenes to transport the hydraulic oil to the first connecting pipe to replenish the second hydraulic motor, thereby preventing the hydraulic oil in the first connecting pipe from being sucked out.

[0023] When the construction machinery turns left and moves backward, the turning radius of the left front wheel is small, and the speed of the first hydraulic motor is slow. The turning radius of the right front wheel is large, and the speed of the second hydraulic motor is fast. The hydraulic oil entering from the second hydraulic motor gathers in the first connecting pipe, causing the pressure of the hydraulic oil in the first connecting pipe to increase and be significantly higher than the pressure on the side of the oil port C2 of the second hydraulic motor, resulting in a pressure holding trend. At this time, the oil replenishing part intervenes to transport part of the hydraulic oil in the first connecting pipe to the third connecting pipe to replenish the second hydraulic motor, avoiding pressure holding in the first connecting pipe and ensuring the reliable and effective operation of the two hydraulic motors. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 is a schematic diagram of a hydraulic control system provided in the prior art;

[0025] Figure 2 It is a schematic diagram of the hydraulic control system provided by the utility model;

[0026] Figure 3 It is a schematic diagram of the chassis of the engineering machinery provided by the utility model.

[0027] In the figure:

[0028] 1', oil tank; 2', oil pump; 3', reversing valve; 4', first hydraulic motor; 5', second hydraulic motor;

[0029] 1. Fuel tank;

[0030] 2. Oil pump;

[0031] 3. Directional valve;

[0032] 4. The first hydraulic motor;

[0033] 5. Second hydraulic motor;

[0034] 61. Shuttle valve; 62. Throttle element;

[0035] 7. Driving motor;

[0036] 8. Overflow valve;

[0037] 91. First connecting pipe; 92. Second connecting pipe; 93. Third connecting pipe; 94. Oil return pipe.

[0038] 10. Chassis; 101. Left front wheel; 102. Right front wheel. DETAILED DESCRIPTION

[0039] The present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are only used to explain the present invention, rather than to limit the present invention. It should also be noted that, for ease of description, only the parts related to the present invention, rather than all structures, are shown in the accompanying drawings.

[0040] In the description of the present invention, unless otherwise clearly specified and limited, the terms "connected", "connected", and "fixed" 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 or an electrical connection; 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. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0041] In the present utility model, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0042] In the description of this embodiment, the terms "upper", "lower", "right", etc., are based on the directions or positions shown in the drawings, and are only for the convenience of description and simplified operation, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as a limitation of the present invention. In addition, the terms "first" and "second" are only used to distinguish in the description and have no special meaning.

[0043] This embodiment provides an engineering machine. Figure 3As shown, the engineering machine includes a chassis 10, on which a left front wheel 101 and a right front wheel 102 are arranged. This embodiment also provides a hydraulic control system, referring to Figure 2 As shown, the hydraulic control system includes an oil tank 1, an oil pump 2, a reversing valve 3, a first hydraulic motor 4, a second hydraulic motor 5 and an oil replenishing member; wherein, the oil inlet of the oil pump 2 is connected to the oil tank 1, the oil outlet of the oil pump 2 is connected to the oil inlet of the reversing valve 3, the oil outlet of the reversing valve 3 is connected to the oil tank 1, the working oil port A1 of the reversing valve 3 is connected to the oil port B1 of the first hydraulic motor 4, the oil port B2 of the first hydraulic motor 4 is connected to the oil port C1 of the second hydraulic motor 5 through the first connecting pipe 91, and the oil port C2 of the second hydraulic motor 5 is connected to the working oil port A2 of the reversing valve 3 through the third connecting pipe 93. The oil replenishing member is connected to the first connecting pipe 91 and the third connecting pipe 93, and the oil replenishing member is used to deliver hydraulic oil to the first connecting pipe 91, or to deliver the hydraulic oil of the first connecting pipe 91 to the third connecting pipe 93. The first hydraulic motor 4 is connected to the left front wheel 101 and is used to drive the left front wheel 101 to rotate, and the second hydraulic motor 5 is connected to the right front wheel 102 and is used to drive the right front wheel 102 to rotate.

[0044] In this embodiment, the first hydraulic motor 4 and the second hydraulic motor 5 are arranged in series through the first connecting pipe 91. The first hydraulic motor 4 and the second hydraulic motor 5 respectively drive the left front wheel 101 and the right front wheel 102 of the engineering machinery to rotate. Specifically, when the engineering machinery is moving forward, the left position of the reversing valve 3 is in the working position, the oil pump 2 is working, and the hydraulic oil in the oil tank 1 is first delivered to the first hydraulic motor 4 through the oil inlet of the reversing valve 3, the working oil port A1 of the reversing valve 3, and the oil port B1 of the first hydraulic motor 4, and then flows through the oil port B2 of the first hydraulic motor 4, the first connecting pipe 91, and the oil port C1 of the second hydraulic motor 5 to the second hydraulic motor 5, and then the hydraulic oil is output through the oil port C2 of the second hydraulic motor 5, the third connecting pipe 93, the working oil port A2 of the reversing valve 3, and the oil outlet of the reversing valve 3, and finally returns to the oil tank 1. The right position of the reversing valve 3 is in the working position, the oil pump 2 is working, and the hydraulic oil in the oil tank 1 is first transported to the second hydraulic motor 5 through the oil inlet of the reversing valve 3, the working oil port A2 of the reversing valve 3, the third connecting pipe 93, and the oil port C2 of the second hydraulic motor 5, and then flows through the oil port C1 of the second hydraulic motor 5, the first connecting pipe 91, and the oil port B2 of the first hydraulic motor 4 to be transported to the first hydraulic motor 4, and then the hydraulic oil is output through the oil port B1 of the first hydraulic motor 4, the working oil port A1 of the reversing valve 3, and the oil outlet of the reversing valve 3, and finally returns to the oil tank 1.

[0045] In this embodiment, when the construction machinery turns left and moves forward, the turning radius of the left front wheel 101 is small, and the rotation speed of the first hydraulic motor 4 is slow. The turning radius of the right front wheel 102 is large, and the rotation speed of the second hydraulic motor 5 is fast. There will be a tendency for the second hydraulic motor 5 to suck out the hydraulic oil in the first connecting pipe 91. At this time, the oil replenishing component intervenes to transport the hydraulic oil to the first connecting pipe 91 to replenish the second hydraulic motor 5, thereby preventing the hydraulic oil in the first connecting pipe 91 from being sucked out.

[0046] When the construction machinery turns left and moves backward, the left front wheel 101 has a small turning radius and the first hydraulic motor 4 has a slow rotation speed, while the right front wheel 102 has a large turning radius and the second hydraulic motor 5 has a fast rotation speed. The hydraulic oil entering from the second hydraulic motor 5 gathers in the first connecting pipe 91, causing the pressure of the hydraulic oil in the first connecting pipe 91 to increase and be significantly higher than the pressure on the side of the oil port C2 of the second hydraulic motor 5, resulting in a pressure holding trend. At this time, the oil replenishing component intervenes to transport part of the hydraulic oil in the first connecting pipe 91 to the third connecting pipe 93 to replenish the second hydraulic motor 5, avoiding pressure holding in the first connecting pipe 91 and ensuring reliable and effective operation of the two hydraulic motors.

[0047] In this embodiment, the oil replenishing component includes a shuttle valve 61, the oil port D1 of the shuttle valve 61 is connected to the connecting pipeline between the working oil port A1 of the reversing valve 3 and the oil port B1 of the first hydraulic motor 4, the oil port D2 of the shuttle valve 61 is connected to the third connecting pipe 93, and the oil port D3 of the shuttle valve 61 is connected to the first connecting pipe 91. Specifically, when there is a tendency for the second hydraulic motor 5 to suck out the hydraulic oil in the first connecting pipe 91, the shuttle valve 61 automatically intervenes, specifically, the oil port D1 and the oil port D3 of the shuttle valve 61 are connected, and part of the hydraulic oil in the connecting pipeline between the working oil port A1 of the reversing valve 3 and the oil port B1 of the first hydraulic motor 4 is transported to the first connecting pipe 91 through the oil port D1 and the oil port D3 of the shuttle valve 61 to replenish the oil for the second hydraulic motor 5, thereby avoiding the hydraulic oil in the first connecting pipe 91 from being sucked out; when the pressure of the hydraulic oil in the first connecting pipe 91 increases and is significantly higher than the pressure on the side of the oil port C2 of the second hydraulic motor 5, resulting in a pressure build-up tendency, the shuttle valve 61 automatically intervenes, specifically, the oil port D2 and the oil port D3 of the shuttle valve 61 are connected, and part of the hydraulic oil in the first connecting pipe 91 is transported to the third connecting pipe 93 through the oil port D2 and the oil port D3 of the shuttle valve 61 to replenish the oil for the second hydraulic motor 5, thereby avoiding pressure build-up in the first connecting pipe 91.

[0048] In this embodiment, the reversing valve 3 is set as a three-position four-way electromagnetic reversing valve 3. The electromagnetic reversing valve 3 has fast control response, reliable and effective action, and convenient operation.

[0049] Furthermore, the oil replenishing member further includes a throttling member 62, the oil port D3 of the shuttle valve 61 is connected to the first connecting pipe 91 through the second connecting pipe 92, and the throttling member 62 is arranged on the second connecting pipe 92. By providing the throttling member 62, the flow rate of the hydraulic oil flowing through the second connecting pipe 92 can be reduced, and a certain throttling effect is played.

[0050] Specifically, the throttle member 62 is configured as a throttle valve. Preferably, the throttle opening of the throttle valve is configured to be adjustable.

[0051] The present embodiment is not limited thereto, and the throttling member 62 may also be configured as a throttling orifice plate or other throttling elements.

[0052] It is worth mentioning that in some other optional embodiments, the oil replenishing member can also be set as a combination of a first oil pipeline, a second oil pipeline, a first switch valve and a second switch valve (the first oil pipeline, the second oil pipeline, the first switch valve and the second switch valve are not shown in the figure). Specifically, the two ends of the first oil pipeline are connected to the oil tank 1 and the first connecting pipe 91 respectively, the first switch valve is arranged on the first oil pipeline, the two ends of the second oil pipeline are connected to the first connecting pipe 91 and the third connecting pipe 93 respectively, and the second switch valve is arranged on the second oil pipeline. Specifically, when there is a tendency for the second hydraulic motor 5 to suck out the hydraulic oil in the first connecting pipe 91, the oil replenishing component intervenes, specifically the first switch valve is opened, and the hydraulic oil is transported to the first connecting pipe 91 through the first oil pipe to replenish the oil for the second hydraulic motor 5, thereby preventing the hydraulic oil in the first connecting pipe 91 from being sucked out; when the pressure of the hydraulic oil in the first connecting pipe 91 increases and is significantly higher than the pressure on the side of the oil port C2 of the second hydraulic motor 5, resulting in a pressure build-up tendency, the oil replenishing component intervenes, specifically the second oil pipe is opened, and part of the hydraulic oil in the first connecting pipe 91 is transported to the third connecting pipe 93 through the second oil pipe to replenish the oil for the second hydraulic motor 5, thereby preventing pressure build-up in the first connecting pipe 91.

[0053] In this embodiment, continue to refer to Figure 2 As shown, the hydraulic control system further includes a drive motor 7, which is connected to the oil pump 2 and drives the oil pump 2 to work. In this embodiment, the speed of the drive motor 7 is adjustable, thereby driving the oil pump 2 to work under different pumping conditions.

[0054] In this embodiment, the hydraulic control system further includes a relief valve 8, the oil inlet of the relief valve 8 is connected to the connecting pipeline between the oil pump 2 and the oil inlet of the reversing valve 3, and the oil outlet of the relief valve 8 is connected to the oil tank 1. The setting of the relief valve 8 can protect the entire hydraulic control system pipeline from overpressure and play a role in ensuring safe overflow.

[0055] In this embodiment, the oil outlet of the relief valve 8 and the oil outlet of the reversing valve 3 converge into the oil return pipe 94, and the oil return pipe 94 is connected to the oil tank 1. Such an arrangement can further simplify the piping layout of the hydraulic control system.

[0056] As an optional embodiment, the hydraulic control system further includes a filtering device (not shown), which is disposed on the connecting pipeline between the oil tank 1 and the oil inlet of the oil pump 2. By providing the filtering device, impurities in the hydraulic oil recirculation process can be effectively removed to ensure the purity of the hydraulic oil.

[0057] Obviously, the above embodiments of the present invention are merely examples for the purpose of clearly illustrating the present invention, and are not intended to limit the implementation methods of the present invention. For those skilled in the art, various obvious changes, readjustments and substitutions can be made without departing from the scope of protection of the present invention. It is not necessary and impossible to list all implementation methods here. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention shall be included in the scope of protection of the claims of the present invention.

Claims

1. A hydraulic control system, characterized in that: It comprises an oil tank (1), an oil pump (2), a reversing valve (3), a first hydraulic motor (4), a second hydraulic motor (5) and an oil replenishing component; wherein: The oil inlet of the oil pump (2) is connected to the oil tank (1), the oil outlet of the oil pump (2) is connected to the oil inlet of the reversing valve (3), the oil outlet of the reversing valve (3) is connected to the oil tank (1), the working oil port A1 of the reversing valve (3) is connected to the oil port B1 of the first hydraulic motor (4), the oil port B2 of the first hydraulic motor (4) is connected to the oil port C1 of the second hydraulic motor (5) through the first connecting pipe (91), and the oil port C2 of the second hydraulic motor (5) is connected to the working oil port A2 of the reversing valve (3) through the third connecting pipe (93); The oil replenishing member is connected to the first connecting pipe (91) and the third connecting pipe (93), and is used to deliver hydraulic oil to the first connecting pipe (91), or to deliver the hydraulic oil in the first connecting pipe (91) to the third connecting pipe (93).

2. The hydraulic control system according to claim 1, characterized in that: The oil replenishing component comprises a shuttle valve (61), an oil port D1 of the shuttle valve (61) being connected to a connecting pipeline between a working oil port A1 of the reversing valve (3) and an oil port B1 of the first hydraulic motor (4), an oil port D2 of the shuttle valve (61) being connected to the third connecting pipe (93), and an oil port D3 of the shuttle valve (61) being connected to the first connecting pipe (91).

3. The hydraulic control system according to claim 2, characterized in that: The oil replenishing component further comprises a throttling component (62); the oil port D3 of the shuttle valve (61) is connected to the first connecting pipe (91) via a second connecting pipe (92); and the throttling component (62) is arranged on the second connecting pipe (92).

4. The hydraulic control system according to claim 3, characterized in that: The throttling element (62) is configured as a throttle valve.

5. The hydraulic control system according to claim 1, characterized in that: It also includes a driving motor (7), which is connected to the oil pump (2) and is used to drive the oil pump (2) to work.

6. The hydraulic control system according to claim 1, characterized in that: It also includes an overflow valve (8), the oil inlet of the overflow valve (8) is connected to the connecting pipeline between the oil pump (2) and the oil inlet of the reversing valve (3), and the oil outlet of the overflow valve (8) is connected to the oil tank (1).

7. The hydraulic control system according to claim 6, characterized in that: The oil outlet of the overflow valve (8) and the oil outlet of the reversing valve (3) converge into an oil return pipe (94), and the oil return pipe (94) is connected to the oil tank (1).

8. The hydraulic control system according to claim 1, characterized in that: The reversing valve (3) is configured as a three-position, four-way electromagnetic reversing valve.

9. The hydraulic control system according to claim 1, characterized in that: It also comprises a filtering device, which is arranged on the connecting pipeline between the oil tank (1) and the oil inlet of the oil pump (2).

10. An engineering machine, characterized in that: It comprises a chassis (10), and also comprises a hydraulic control system as claimed in any one of claims 1 to 9; wherein: The chassis (10) is provided with a left front wheel (101) and a right front wheel (102); The first hydraulic motor (4) is connected to the left front wheel (101) and is used to drive the left front wheel (101) to rotate; The second hydraulic motor (5) is connected to the right front wheel (102) and is used to drive the right front wheel (102) to rotate.

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