CN111943099A - An energy-saving hydraulic system - Google Patents

Abstract

The invention discloses an energy-saving hydraulic system for high-altitude work vehicles, comprising a power unit, an execution unit, a main hydraulic system, a sensing unit and a control unit. The hydraulic lifting control system for adjusting the lifting and lowering of the working platform and the hydraulic rotation control system for controlling the rotation of the turntable, the main hydraulic system includes a stop valve, an electric proportional relief valve and a reversing valve connecting the hydraulic systems of the execution unit, and a sensing unit. It includes a long-angle sensor for measuring the position of the work platform and a load cell for measuring the load capacity of the work platform, and the control unit is used to control the power unit and the main hydraulic system. Through the cooperation of various components, the invention can control the motor speed and the overflow pressure value according to the working requirements of the aerial work vehicle, so as to control the energy consumption of the whole equipment and the loss of hydraulic energy, and improve the energy saving effect.

Description

An energy-saving hydraulic system

technical field

The invention relates to the field of hydraulic technology, in particular to an energy-saving hydraulic system.

Background technique

Aerial work vehicle is an advanced aerial work machine, which can improve the work efficiency, safety and comfort of aerial construction personnel, and reduce labor intensity. It is widely used in engineering construction, industrial installation, equipment maintenance, plant maintenance, shipbuilding, electric power, Municipal, airport, communication, garden and other fields. The existing aerial work platforms mainly include scissor-type aerial work vehicles, straight-arm aerial work vehicles, and articulated-arm aerial work vehicles, most of which are driven by hydraulic energy. How to improve the utilization efficiency and effective control of hydraulic energy Energy loss, but also to ensure its functionality has become an urgent problem to be solved.

SUMMARY OF THE INVENTION

In order to solve the above technical problems, the purpose of the present invention is to provide an energy-saving hydraulic system, which can reduce the loss of hydraulic energy, and at the same time can effectively control the overall energy loss of the equipment, and has a good energy-saving effect.

The invention provides an energy-saving hydraulic system, which is applied to an aerial work vehicle. The aerial work vehicle includes a chassis, a turntable, a boom and a work platform, and is characterized in that the energy-saving hydraulic system includes:

a power unit, which has a hydraulic pump and a motor, an oil suction port of the hydraulic pump is connected to an oil tank, and the motor is connected to the hydraulic pump;

an execution unit, which includes a hydraulic lift control system and a hydraulic rotation control system, the hydraulic lift control system is connected to the boom for controlling the boom to extend and retract to adjust the lifting and lowering of the work platform, and the hydraulic rotation control system is connected to the turntable for controlling the rotation of the turntable;

The main hydraulic system has a shut-off valve, an electric proportional relief valve and a reversing valve connected in sequence, the shut-off valve is arranged between the hydraulic pump and the electric proportional relief valve, and the reversing valve is arranged in the Between the electric proportional relief valve and the execution unit, the reversing valve is provided with two or more hydraulic systems respectively connected to the execution unit;

The sensing unit includes a long-angle sensor and a load cell, the long-angle sensor is provided on the boom for measuring the position of the work platform, and the load cell is provided on the work platform for measuring the load on the work platform. weight;

A control unit is connected with the power unit, the main hydraulic system and the sensing unit, and the control unit is configured to receive the data measured by the sensing unit and perform calculation to control the power unit and the main hydraulic system to work.

Preferably, the hydraulic lift control system includes:

A main boom hydraulic control system, which includes a main boom oil cylinder;

Leveling hydraulic control system, which includes main leveling oil cylinder and auxiliary leveling oil cylinder;

A jib hydraulic control system includes a jib oil cylinder.

Preferably, the reversing valve includes:

The first reversing valve is arranged between the electric proportional relief valve and the main arm oil cylinder;

The second reversing valve is arranged between the electric proportional relief valve and the leveling hydraulic control system;

The third reversing valve is arranged between the electric proportional relief valve and the hydraulic rotation control system;

The fourth reversing valve is arranged between the electric proportional relief valve and the auxiliary arm oil cylinder.

Preferably, a double balance valve is provided between the rod cavity and the cavityless rod of the auxiliary leveling oil cylinder.

Preferably, the hydraulic rotation control system includes a hydraulic motor with a brake and a shuttle valve, and the shuttle valve is connected in parallel with the reversing valve in three parallel.

Preferably, a second double balance valve is provided between the hydraulic motor and the third reversing valve.

Preferably, the execution unit further includes a hydraulic float control system, the hydraulic float control system is connected with the hydraulic pump through the reversing valve 5, and the hydraulic float control system is used to adjust the swing of the front axle of the chassis.

Preferably, the main hydraulic system further includes a pressure reducing valve, and the pressure reducing valve is arranged between the hydraulic pump and the reversing valve 5 .

Preferably, the main hydraulic system further includes a relief valve, and the relief valve is arranged between the leveling hydraulic control system and the oil return port of the oil tank.

Preferably, the main hydraulic system further includes an adjustable flow valve, and the adjustable flow valve is arranged between the second reversing valve and the electric proportional relief valve.

The energy-saving hydraulic system provided by the present invention, through the cooperation of the power unit, the execution unit, the main hydraulic system, the sensing unit and the control unit, can match the corresponding overflow pressure value when performing different actions according to the operation requirements, In order to reduce the loss of hydraulic energy due to the high overflow pressure of the system, at the same time, the speed of the motor is jointly controlled by the control unit to realize the control of the overall energy loss and achieve the effect of energy saving.

Description of drawings

In order to explain the embodiments of the present invention or the technical solutions in the prior art more clearly, the following briefly introduces the accompanying drawings that need to be used in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description are only These are some embodiments described in the present invention. For those of ordinary skill in the art, other drawings can also be obtained based on these drawings without any creative effort.

1 is a schematic diagram of an energy-saving hydraulic system according to an embodiment of the present invention;

FIG. 2 is a structural diagram of the application of the energy-saving hydraulic system of an embodiment of the present invention to an aerial work vehicle;

FIG. 3 is an enlarged view of part A in FIG. 2 .

Among them, 1, power unit, 2, execution unit, 3, main hydraulic system, 4, fuel tank, 5, long angle sensor, 6, load cell, 7, first filter, 8, second filter, 11, Hydraulic pump, 12, motor, 21, hydraulic lift control system, 22, hydraulic rotation control system, 23, hydraulic float control system, 31, globe valve, 32, electric proportional relief valve, 33, relief valve, 34, joint Flow valve, 35, reversing valve, 5, 36, pressure reducing valve, 91, chassis, 92, turntable, 93, boom, 94, work platform, 211, main boom cylinder, 212, main leveling cylinder, 213, auxiliary Leveling Cylinder, 214, Jib Cylinder, 215, Double Balance Valve One, 221, Brake, 222, Hydraulic Motor, 223, Shuttle Valve, 224, Double Balance Valve Two, 231, Front Axle Left Cylinder, 232, Front Axle Right Cylinder, 361, reversing valve one, 362, reversing valve two, 363, reversing valve three, 364, reversing valve four, S, oil suction port, T, oil return port.

Detailed ways

In order to make those skilled in the art better understand the technical solutions of the present invention, the present invention will be described in detail below with reference to the accompanying drawings. The description in this part is only exemplary and explanatory, and should not have any limiting effect on the protection scope of the present invention. .

It should be noted that like numerals refer to like items in the following figures, so once an item is defined in one figure, it does not require further definition and explanation in subsequent figures.

It should be noted that the orientation or positional relationship indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. Based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship that the product of the invention is usually placed in use, it is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the indicated device or element must be It has a specific orientation, is constructed and operates in a specific orientation, and therefore should not be construed as a limitation of the present invention. Furthermore, the terms "first", "second", etc. are only used to differentiate the description and should not be construed to indicate or imply relative importance.

Furthermore, the terms "horizontal", "vertical", "overhanging" etc. do not imply that a component is required to be absolutely horizontal or overhang, but rather may be slightly inclined. For example, "horizontal" only means that its direction is more horizontal than "vertical", it does not mean that the structure must be completely horizontal, but can be slightly inclined.

In the description of the present invention, it should also be noted that, unless otherwise expressly specified and limited, the terms "arranged", "installed", "connected" and "connected" should be understood in a broad sense, for example, it may be a fixed connection, It can also be 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, or the internal communication between the two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood in specific situations.

Referring to FIGS. 1 to 2, an energy-saving hydraulic system is applied to an aerial work vehicle. The aerial work vehicle includes a chassis 91, a turntable 92, a boom 93 and a working platform 94. The energy-saving hydraulic system includes:

The power unit 1 has a hydraulic pump 11 and a motor 12, the oil suction port S of the hydraulic pump 11 is connected to the oil tank 4, and the motor 12 is connected to the hydraulic pump 11;

The execution unit 2 includes a hydraulic lift control system 21 and a hydraulic rotation control system 22. The hydraulic lift control system 21 is connected to the boom 93 for controlling the boom 93 to extend and retract to adjust the lifting and lowering of the work platform 94. The hydraulic rotation control system 22 is connected to the turntable 92 for use Rotate on the control turntable 92;

The main hydraulic system 3 has a shut-off valve 31 connected in sequence, an electric proportional relief valve 32 and a reversing valve, the shut-off valve 31 is arranged between the hydraulic pump 11 and the electric proportional relief valve 32, and the reversing valve is arranged in the Between the electric proportional relief valve 32 and the execution unit 2, the reversing valve is provided with two or more hydraulic systems respectively connected to the execution unit 2;

The sensing unit includes a long-angle sensor 5 and a load cell 6, the long-angle sensor 5 is arranged on the boom 93 for measuring the position of the work platform 94, and the load cell 6 is set on the work platform 94 for measuring the work platform load on 94;

The control unit is connected with the power unit 1 , the main hydraulic system 3 and the sensing unit. The control unit is used for receiving the data measured by the sensing unit and performing calculations to control the power unit 1 and the main hydraulic system 3 to work.

Among them, the power unit 1 mainly sucks pressure oil from the oil tank 4 to the main hydraulic system 3 through the hydraulic pump 11, and the motor 12 is used to drive the hydraulic pump 11 to work. In order to facilitate the control of the work and steering of the aerial work vehicle, the hydraulic pump 11 can Set to double hydraulic pump.

Wherein, the execution unit 2 is used to control the rotation of the turntable 92 of the aerial work platform and control the lifting and retraction of the boom 93 to adjust the height and working range of the work platform 94 .

Among them, the main hydraulic system 3 is set between the power unit 1 and the execution unit 2, and there can be two cut-off valves 31, which are respectively connected to the two pumps of the hydraulic pump 11; the electric proportional relief valve 32 is connected to the cut-off valve 31 and the execution unit. Between units 2, different voltages can be input to the electromagnet of the electric proportional relief valve 32, so that the generated thrust changes, thereby obtaining different hydraulic pressures; there are more than two reversing valves, which are connected to the electric proportional Between the relief valve 32 and each hydraulic system of the execution unit 2 , it is used to connect the hydraulic pump 11 with the oil circuit of each hydraulic system to realize the communication, cutoff or reversal of hydraulic oil.

Specifically, the hydraulic lift control system 21 may include:

The main boom hydraulic control system, which includes the main boom oil cylinder 211 for driving the boom lift and retraction on the boom frame 93;

A leveling hydraulic control system, which includes a main leveling oil cylinder 212 and an auxiliary leveling oil cylinder 213 for leveling the working platform 94;

The jib hydraulic control system includes a jib oil cylinder 214 for driving the jib on the jib frame 93 to work.

Diverter valves can include:

The reversing valve one 361 is set between the electric proportional relief valve 32 and the main arm oil cylinder 211;

The second reversing valve 362 is located between the electric proportional relief valve 32 and the leveling hydraulic control system;

The reversing valve three 363 is arranged between the electric proportional relief valve 32 and the hydraulic rotation control system 22;

The reversing valve four 364 is arranged between the electric proportional relief valve 32 and the jib oil cylinder 214 .

Among them, the reversing valve 1 361 and the reversing valve 4 364 can both be set as three-position four-way electro-hydraulic valves, and the reversing valve 2 362 and the reversing valve 3 363 can be set as three-position four-way solenoid valves.

The hydraulic rotation control system 22 may include a hydraulic motor 222 with a brake 221 and a shuttle valve 223. The shuttle valve 223 is connected in parallel with the reversing valve 3 363. In order to control the flow of hydraulic oil on the hydraulic rotation control system 22, the shuttle valve 223 can A throttle valve is provided between the valve 223 and the brake 221 .

The long-angle sensor 5 in the sensing unit is used to measure the specific position and size of the work platform 94, and the load cell 6 is used to measure the load on the work platform 94, and sense the measured data to the control unit.

Among them, the control unit is used for receiving the data transmitted by the sensing unit, and transmits the matched characteristic curve to the controller of the motor 12 and the electric proportional relief valve 32 of the main hydraulic system after the program operation.

The working principle of this embodiment is as follows:

When the aerial work vehicle needs to perform steering action, it is assumed that the set steering pressure is 10MPa, and the flow required by the system is small at this time, and the motor characteristic curve with low power and high energy efficiency is transmitted to the controller of the motor 12 through the control unit, and the Acting on the motor 12, at the same time, the control unit sends a 10MPa command to the electric proportional relief valve 32, and controls one of the hydraulic pumps 11 to open through the control unit, and the other one does not work. At this time, the hydraulic rotation control in the execution unit 2 The oil circuit of the system 22 is communicated and can drive the turntable 92 to rotate.

When the aerial work vehicle needs to perform a lifting action, the control unit transmits high power to the controller of the motor 12 through the control unit according to the data transmitted by the long angle sensor 5 and the weighing sensor 6 in the sensing unit and after the program calculation. , the motor characteristic curve with high torque, and acts on the motor 12, at the same time the control unit sends pressure to the electric proportional relief valve 32 (the pressure value can be set to 14Mpa at no load, and the pressure value can be set to 16MPa at full load), and Both pumps of the hydraulic pump 11 are controlled by the control unit to be turned on. At this time, the oil circuit of the hydraulic lifting control system 21 in the execution unit 2 is connected, and the boom 93 can be driven to extend and retract to adjust the lifting and lowering of the working platform 94 .

It can be seen that the energy-saving hydraulic system provided by the present invention, through the cooperation of the power unit, the execution unit, the main hydraulic system, the sensing unit and the control unit, can match the corresponding overflow when performing different actions according to different operation requirements. The flow pressure value is adjusted to reduce the loss of hydraulic energy due to the high overflow pressure of the system. At the same time, the speed of the motor is jointly controlled by the control unit to control the overall energy loss and achieve the effect of energy saving.

Further, in order to adjust the working platform 94 to keep it level, a double balance valve 1 215 can be arranged between the rod cavity and the cavityless rod of the auxiliary leveling oil cylinder 213 .

Further, in order to adjust the rotation of the turntable 92 easily, a second double balance valve 224 can be provided between the hydraulic motor 222 and the fourth reversing valve 364 .

As a preferred embodiment, in order to improve the balance of the aerial work vehicle during driving, the execution unit 2 may further include a hydraulic float control system 23. The hydraulic float control system 23 is connected with the hydraulic pump 11 through the reversing valve 35, and the hydraulic float The control system 23 is used to adjust the swing of the front axle of the chassis 91 .

The hydraulic floating control system 23 may include a left front axle oil cylinder 231 and a front axle right oil cylinder 232. Both the front axle left oil cylinder 231 and the front axle right oil cylinder 232 are connected with a balance valve, and the pressure oil is supplied to the front axle through the balance valve. left and right cylinders.

Wherein, the reversing valve five 35 can be set as a two-position three-way solenoid valve.

Wherein, in order to adjust the pressure of the hydraulic float control system 23 , the main hydraulic system 3 may further include a pressure reducing valve 36 , and the pressure reducing valve 36 is arranged between the hydraulic pump 11 and the reversing valve 5 35 .

Further, the main hydraulic system 3 may further include a relief valve 33 , and the relief valve 33 is provided between the leveling hydraulic control system and the oil return port T of the oil tank 4 .

Further, the main hydraulic system 3 further includes an adjustable flow valve 34 , and the adjustable flow valve 34 is arranged between the reversing valve 363 and the electric proportional relief valve 32 .

Further, in order to improve the cleaning of the pressure oil and ensure the normal operation of the main hydraulic system 3 , a first filter 7 may be provided on the pipeline connecting the shut-off valve 31 and the electric proportional relief valve 32 .

Similarly, a second filter 8 can be provided on the oil return pipeline of the hydraulic lift control system 21 and the hydraulic rotation control system 22 and the oil tank 4 .

It should be noted that, herein, the terms "comprising", "comprising" or any other variation thereof are intended to encompass non-exclusive inclusion, such that a process, method, article or device comprising a series of elements includes not only those elements, It also includes other elements not expressly listed or inherent to such a process, method, article or apparatus.

The principles and implementations of the present invention are described herein by using specific examples, and the descriptions of the above examples are only used to help understand the method and the core idea of the present invention. The above are only the preferred embodiments of the present invention. It should be pointed out that due to the limitedness of written expressions, there are objectively unlimited specific structures. For those of ordinary skill in the art, without departing from the principles of the present invention, Several improvements, modifications or changes can also be made, and the above-mentioned technical features can also be combined in an appropriate manner; these improvements, modifications, changes or combinations, or the idea and technical solution of the invention are directly applied to other occasions without improvement, All should be regarded as the protection scope of the present invention.

Claims (10)

1. An energy-saving hydraulic system, applied to an aerial work vehicle, comprising a chassis (91), a turntable (92), a boom (93) and a working platform (94), wherein the energy-saving hydraulic system includes : A power unit (1) has a hydraulic pump (11) and a motor (12), an oil suction port (S) of the hydraulic pump (11) is connected to an oil tank (4), and the motor (12) is connected to the hydraulic pump ( 11) Connection; An execution unit (2), comprising a hydraulic lift control system (21) and a hydraulic rotation control system (22), the hydraulic lift control system (21) being connected to the boom (93) for controlling the boom (93) to extend and retract to adjust The working platform (94) is lifted and lowered, and the hydraulic rotation control system (22) is connected to the turntable (92) for controlling the rotation of the turntable (92); A main hydraulic system (3), which has a shut-off valve (31), an electric proportional relief valve (32) and a reversing valve connected in sequence, the shut-off valve (31) is provided between the hydraulic pump (11) and the Between the electric proportional relief valve (32), the reversing valve is arranged between the electric proportional relief valve (32) and the execution unit (2), and the reversing valve is provided with two or more connecting the hydraulic systems of the execution unit (2); A sensing unit, comprising a long-angle sensor (5) and a load cell (6), the long-angle sensor (5) being provided on the boom (93) for measuring the position of the working platform (94), the weighing The load cell (6) is arranged on the working platform (94) for measuring the load on the working platform (94); A control unit, which is connected with the power unit (1), the main hydraulic system (3) and the sensing unit, the control unit is configured to receive data measured by the sensing unit and perform calculations to control the power unit (1) ) and the main hydraulic system (3) works. 2. The energy-saving hydraulic system according to claim 1, wherein the hydraulic lift control system (21) comprises: A main boom hydraulic control system, which includes a main boom oil cylinder (211); A leveling hydraulic control system, which includes a main leveling oil cylinder (212) and an auxiliary leveling oil cylinder (213); A jib hydraulic control system includes a jib cylinder (214). 3. The energy-saving hydraulic system according to claim 2, wherein the reversing valve comprises: The first reversing valve (361) is arranged between the electric proportional relief valve (32) and the main arm oil cylinder (211); The second reversing valve (362) is arranged between the electric proportional relief valve (32) and the leveling hydraulic control system; A reversing valve three (363), located between the electric proportional relief valve (32) and the hydraulic rotation control system (22); The fourth reversing valve (364) is arranged between the electric proportional relief valve (32) and the auxiliary arm oil cylinder (214). 4. The energy-saving hydraulic system according to claim 2, wherein a double balance valve one (215) is provided between the rod cavity and the cavityless rod of the auxiliary leveling oil cylinder (213). 5. The energy-saving hydraulic system according to claim 3, wherein the hydraulic rotation control system (22) comprises a hydraulic motor (222) with a brake (221) and a shuttle valve (223), the shuttle valve (223) is connected in parallel with the reversing valve three (363). 6. The energy-saving hydraulic system according to claim 3, characterized in that a second double balance valve (224) is provided between the hydraulic motor (222) and the third reversing valve (363). 7. The energy-saving hydraulic system according to claim 1, wherein the execution unit (2) further comprises a hydraulic float control system (23), the hydraulic float control system (23) and the hydraulic pump (11) ) is connected through the reversing valve five (35), and the hydraulic float control system (23) is used to adjust the swing of the front axle of the chassis (91). 8 . The energy-saving hydraulic system according to claim 7 , wherein the main hydraulic system ( 3 ) further comprises a pressure reducing valve ( 36 ), and the pressure reducing valve ( 36 ) is provided in the hydraulic pump ( 11 ). ) and the reversing valve five (35). 9. The energy-saving hydraulic system according to claim 2, characterized in that, the main hydraulic system (3) further comprises a relief valve (33), and the relief valve (33) is provided in the leveling hydraulic control Between the system and the oil return port (T) of the oil tank (4). 10 . The energy-saving hydraulic system according to claim 3 , wherein the main hydraulic system ( 3 ) further comprises an adjustable flow valve ( 34 ), and the adjustable flow valve ( 34 ) is provided in the reversing direction. 11 . Between valve two (362) and the electric proportional relief valve (32).

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