WO2012094900A1

WO2012094900A1 - Apparatus and method for controlling sealed, crane hydraulic winch circuit

Info

Publication number: WO2012094900A1
Application number: PCT/CN2011/079205
Authority: WO
Inventors: 詹纯新; 刘权; 杨勇; 刘琴; 刘永赞; 郭纪梅; 李英智; 胡廷江
Original assignee: 长沙中联重工科技发展股份有限公司; 湖南中联重科专用车有限责任公司
Priority date: 2011-01-14
Filing date: 2011-08-31
Publication date: 2012-07-19
Also published as: CN102583157A; CN102583157B

Abstract

An apparatus for controlling a sealed, crane hydraulic winch circuit and a method for controlling same. The sealed, crane hydraulic winch circuit comprises a hydraulic pump and a brake. After completion of each winch action, the pressure within the hydraulic pump and the direction of the winch action at the time when the brake shuts off are stored by the controlling apparatus; and when running the current winch action, the brake is turned-on on the basis of the pressure stored and the direction of the previous winch action. Prevention of load slipping is ensured by the apparatus for controlling the sealed, crane hydraulic winch circuit, wearing on the hydraulic pump is reduced, and stability and speed of winch action run by the sealed, crane hydraulic winch circuit are improved.

Description

Control device and method for closed hydraulic hoisting circuit of crane

Technical field

The present invention relates to a control device, and in particular to a control device and method for a closed hydraulic winch circuit of a crane. Background technique

The hydraulic hoisting circuit used in the current construction machinery is generally an open circuit. The open circuit is provided with a balancing valve. When the hydraulic pump provides sufficient lifting pressure, the balancing valve will open, and generally does not occur due to the brake. The uncontrollable load slip phenomenon caused by premature opening, but the open circuit has the following three disadvantages: (1) Composite operation control is difficult; (2) The pipeline is complicated, the installation space is large, and the required hydraulic tank volume is larger. , the realization cost is higher; and (3) cavitation is easier to form due to the absence of the oil filling system in the open circuit.

In order to solve the defects of the above open circuit, a closed hydraulic hoisting circuit of the crane is proposed, and Chinese patent CN. 200946070Y discloses a secondary lifting control device for the closed hydraulic hoisting circuit of the crane. The control device stores the pressure of the hydraulic pump when the brake is last closed, and obtains the pressure in the hydraulic pump on the circuit before performing the next hoisting operation, and when the pressure reaches or exceeds the pressure stored by the control device, the brake is opened, thereby opening the brake Perform the next hoisting action.

In fact, as long as the hydraulic pump can establish the pressure, there is no uncontrollable slippage, because the pressure in the hydraulic pump will increase rapidly as the load increases. However, if the pressure established when the brake is opened is not appropriate, an instantaneous slip or lift may occur after the brake is opened, which is not conducive to the stability of the load lifting or lowering.

In the secondary lifting control device disclosed in the above Chinese patent CN. 200946070Y, the brake is opened when the lifting operation is performed according to the pressure of the hydraulic pump when the brake is last closed. It is not reasonable, for example, when the last hoisting action is lifting, the pressure stored in the control device is the sum of the gravity of the load, the frictional force during lifting, and the force for lifting the acceleration, if this value is used. The pressure threshold of the brake opening will cause the following problems due to the high pressure threshold: (1) The phenomenon that the load will jump instantaneously when the brake is opened, which is not conducive to the stable lifting or lowering of the load; (2) The hydraulic pump before the brake is opened The pressure built in is too high, resulting in excessive consumption of the hydraulic pump, and the time required to establish pressure in the hydraulic pump is too long, which also affects the rapidity of the control device. Summary of the invention

The object of the present invention is to provide a control device and method for a closed hydraulic hoisting circuit of a crane, which can improve the hoisting operation of a closed hydraulic hoisting circuit of a crane without ensuring a load drop phenomenon. Stability and rapidity, and reduced wear on the hydraulic pump.

In order to achieve the above object, the present invention provides a control device for a closed hydraulic hoisting circuit of a crane, the closed hydraulic hoisting circuit of the crane comprising a hydraulic pump and a brake, wherein the control device is executed every time a hoisting operation is performed And storing a pressure in the hydraulic pump when the brake is closed and a direction of the hoisting action, and controlling the brake according to the stored pressure and the direction of the last hoisting action when performing the hoisting operation turn on.

Wherein, when the last hoisting action is lifting, the control device controls the brake to be opened when the pressure in the hydraulic pump reaches a first ratio of the stored pressure; and when the last hoisting action is decentralized The control device controls the brake to open when the pressure in the hydraulic pump reaches a second ratio of the stored pressure, and the first ratio may be greater than or equal to 30% and less than 100%, the first The second ratio can be greater than or equal to 50% and less than 100%.

Wherein, the first ratio may be 60-80%, and the second ratio may be greater than or equal to 80% and less than 100%

Wherein, the first ratio may be 70%, and the second ratio may be 90%. Wherein, when the control device controls the brake to be opened, the brake can be controlled to be opened according to the direction of the current winding operation.

Wherein, the control device can control the brake to be opened according to the following strategy: when the last hoisting action is lifting and the hoisting action is lifting, when the pressure in the hydraulic pump reaches the third of the stored pressure When the ratio is proportional, the brake is controlled to be opened; when the last hoisting action is lifting and the hoisting action is lowering, when the pressure in the hydraulic pump reaches the fourth ratio of the stored pressure, the brake is controlled Opening; when the last hoisting action is lowering and the hoisting action is lowering, when the pressure in the hydraulic pump reaches the fifth ratio of the stored pressure, the brake is controlled to be opened; and the previous volume When the lifting action is the lowering and the hoisting action is the lifting, when the pressure in the hydraulic pump reaches the sixth ratio of the stored pressure, the brake is controlled to be opened, and the third ratio and the fifth ratio may be 50-90%, the fourth ratio may be 30-70%, and the sixth ratio may be greater than or equal to 70% and less than 100%.

Wherein, the third ratio and the fifth ratio may be 60-80%, the fourth ratio may be 40-60%, and the sixth ratio may be greater than or equal to 80% and less than 100%.

Wherein, the third ratio and the fifth ratio may be 70%, the fourth ratio may be 50%, and the sixth ratio may be 90%.

The present invention also provides a control method for a closed hydraulic hoisting circuit of a crane, the closed hydraulic hoisting circuit of the crane comprising a hydraulic pump and a brake, the method comprising: storing the brake when each hoisting operation is performed The pressure in the hydraulic pump and the direction of the winding operation, and when the present winding operation is performed, the brake is controlled to be opened according to the stored pressure and the direction of the previous winding operation.

Wherein, when the last hoisting action is lifting, when the pressure in the hydraulic pump reaches a first ratio of the stored pressure, the brake is controlled to open; and when the last hoisting action is lowering, When the pressure in the hydraulic pump reaches a second ratio of the stored pressure, the control controls the brake to open, the first ratio may be greater than or equal to 30% and less than 100%, and the second ratio may be greater than or equal to 50 % and less than 100%. The first ratio may be 60-80%, and the second ratio may be greater than or equal to 80% and less than 100%.

Wherein, the first ratio may be 70%, and the second ratio may be 90%.

Wherein, when the brake is controlled to open, the brake can be controlled to be opened according to the direction of the winding operation.

Wherein, when the last hoisting action is lifting and the hoisting action is lifting, when the pressure in the hydraulic pump reaches a third ratio of the stored pressure, the brake is controlled to open; When the lifting is performed and the hoisting action is lowering, when the pressure in the hydraulic pump reaches the fourth ratio of the stored pressure, the brake is controlled to be opened; the last hoisting action is decentralized and the volume is When the lifting action is the lowering, when the pressure in the hydraulic pump reaches the fifth ratio of the stored pressure, the brake is controlled to be opened; and when the last hoisting action is lowering and the hoisting action is lifting, Then, when the pressure in the hydraulic pump reaches a sixth ratio of the stored pressure, the brake is controlled to be opened, the third ratio and the fifth ratio may be 50-90%, and the fourth ratio may be 30- 70%, the sixth ratio may be greater than or equal to 70% and less than 100%.

The third ratio and the fifth ratio may be 60-80%, and the fourth ratio may be

40-60%, the sixth ratio may be greater than or equal to 80% and less than 100%.

The above solution can appropriately reduce the pressure threshold for opening the brake by considering the direction of the last hoisting action (that is, the threshold value can be lower than the pressure in the hydraulic pump when the brake is closed after the last hoisting operation stored by the control device). This not only saves the time for the hydraulic pump to establish pressure before opening the brake, but also improves the speed of the control device, and also avoids the loss of the hydraulic pump due to the excessive pressure established in the hydraulic pump. In addition, because the pressure in the hydraulic pump changes very rapidly with the load, even if the pressure threshold for opening the brake is appropriately reduced, the load can be lifted or lowered.

Other features and advantages of the present invention will be described in detail in the detailed description that follows. DRAWINGS

The drawings are intended to provide a further understanding of the invention, and are in the In the drawing:

1 is a schematic structural view of a control device for a closed hydraulic hoisting circuit of a crane;

Figure 2 is a graph showing the relationship between the pressure established by the hydraulic pump and the time required to establish the pressure;

Figure 3 is a flow chart of the control method of the closed hydraulic hoisting circuit of the crane. Description of the reference numerals

100 controller 200 pressure sensor

300 proportional solenoid valve 400 switch solenoid valve

500 joysticks

The specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. It is to be understood that the specific embodiments described herein are intended to be illustrative and not restrictive.

The present invention provides a control device for a closed hydraulic hoisting circuit of a crane, the closed hydraulic hoisting circuit of the crane comprising a hydraulic pump and a brake, wherein the control device stores the brake closed every time a hoisting operation is performed When the pressure in the hydraulic pump and the direction of the hoisting operation are performed, and when the hoisting operation is performed, the brake is controlled to be opened according to the stored pressure and the direction of the previous hoisting operation. By considering the direction of the last hoisting action, when the hoisting action is performed, the pressure in the hydraulic pump reaches a certain ratio of the stored pressure. In the case (the ratio is less than 1), the brake is controlled to open. At this time, it is possible to avoid excessive pressure build-up in the hydraulic pump and cause the hydraulic pump to wear out, and the time for establishing the pressure can be saved. In addition, the pressure of the hydraulic pump can be stabilized by the rapid response of the load and the setting of the ratio to ensure the load is lifted or lowered.

Figure 1 is a schematic view showing the structure of a control device for a closed hydraulic hoisting circuit of a crane. As shown in FIG. 1 , the control device of the closed hydraulic hoisting circuit of the crane includes a controller 100 and a pressure sensor 200 electrically connected to the controller 100 , a proportional solenoid valve 300 , a switch solenoid valve 400 , and a joystick 500 . The pressure sensor 200 is located in the hydraulic pump for detecting the pressure in the hydraulic pump; the proportional solenoid valve 300 is located on the hydraulic pump for controlling the flow rate of the hydraulic pump; 400 is located on the brake for controlling opening and closing of the brake; the joystick 500 is used to input a direction of the hoisting action. An embodiment of the control device is given here, but the invention of the present invention lies in the specific control strategy of the control device, so the control device of the present invention is not limited to the specific form shown in FIG. The control device is also feasible. For example, the direction of the hoisting motion may be input without the manipulation of the joystick 500, and input by means of a key input; as for the control of the brake, it may be performed without the switch solenoid valve 400.

Fig. 2 is a graph showing the relationship between the pressure established by the hydraulic pump and the time required to establish the pressure. As shown in Fig. 2, when the pressure P1 is established, the time required to enter the steady state is T1; when the pressure P2 is established, the time required to enter the steady state is T2. Wherein, the pressure P1 is less than the pressure Ρ2, and the time T1 is less than the time Τ2. Therefore, the higher the established pressure, the longer the time required to establish the pressure, and the present invention improves the speed of the control device by reducing the pressure required to build the hydraulic pump.

Specifically, when the last hoisting action is lifting, the control device controls the brake to be opened when the pressure in the hydraulic pump reaches a first ratio of the stored pressure; and when the last hoisting action For lowering, the control device controls the brake to open when the pressure in the hydraulic pump reaches a second ratio of the stored pressure. When the last hoisting action is lifting, the pressure stored by the control device is the gravity of the load, the friction of the lifting, and the lifting. The sum of the forces corresponding to the acceleration; when the last hoisting action is the lowering, the pressure stored by the control device is the difference between the gravity of the load and the force corresponding to the downward acceleration and the friction of the lowering, in view of the previous volume When the lifting action is for lifting and lowering, the magnitude of the pressure stored by the control device is different, so the first ratio may be less than or equal to the second ratio.

Wherein, the first ratio may be greater than or equal to 30% and less than 100%, and the second ratio may be greater than or equal to 50% and less than 100%; experiments show that when the first ratio is 60-80%, the first When the second ratio can be greater than or equal to 80% and less than 100%, the load lifting or lowering stability can be better balanced, the speed of the control device can be avoided, and the hydraulic pump can be prevented from being damaged due to excessive hydraulic pressure. More preferably, the first ratio is 70% and the second ratio is 90%.

Preferably, the control device may also consider the direction of the hoisting action when controlling the opening of the brake. If the direction of the hoisting action is lower, the pressure threshold for opening the brake can be relatively reduced, and the load can be stabilized when the brake is opened; if the direction of the hoisting action is increased, it can be relatively increased. The pressure threshold of the large opening brake can also satisfy the stability of the load when the brake is opened. In this way, the ratio of the direction of the previous and the hoisting action can be further refined to further reduce the pressure threshold for opening the brake, shorten the time for establishing the pressure of the hydraulic pump, and reduce the time when the stability is satisfied. Loss of the hydraulic pump.

Specifically, the control device may control the brake to be opened according to the following strategy: when the last hoisting action is lifting and the hoisting action is lifting, when the pressure in the hydraulic pump reaches the stored pressure In the third ratio, the brake is controlled to be opened; when the last hoisting action is lifting and the hoisting action is lowering, when the pressure in the hydraulic pump reaches the fourth ratio of the stored pressure, the control center The brake is opened; when the last hoisting action is lowering and the hoisting action is lowering, when the pressure in the hydraulic pump reaches the fifth ratio of the stored pressure, the brake is controlled to be opened; When the hoisting action is the lowering and the hoisting action is the lifting, when the pressure in the hydraulic pump reaches the sixth ratio of the stored pressure, the brake is controlled to be opened, and the fourth ratio is smaller than the first The third ratio and the fifth ratio, the third ratio and the fifth ratio are smaller than the sixth ratio. Wherein, the third ratio and the fifth ratio may be 50-90%, the fourth ratio may be 30-70%, and the sixth ratio may be greater than or equal to 70% and less than 100%. Experiments have shown that when the third ratio and the fifth ratio are 60-80%, the fourth ratio is 40-60%, and the sixth ratio is greater than or equal to 80% and less than 100%, it is better Take into account the stability of the load lifting or lowering, the speed of the control device and the loss of the hydraulic pump due to excessive hydraulic pressure. More preferably, the third ratio and the fifth ratio are 70%, the fourth ratio is 50%, and the sixth ratio is 90%.

Correspondingly, the present invention also provides a control method for a closed hydraulic hoisting circuit of a crane, the closed hydraulic hoisting circuit of the crane comprising a hydraulic pump and a brake, the method comprising: performing a hoisting operation every time, storing the storage When the brake is closed, the pressure in the hydraulic pump and the direction of the winding operation are performed, and when the winding operation is performed, the brake is controlled to be opened according to the stored pressure and the direction of the previous winding operation.

Wherein, when the last hoisting action is lifting, when the pressure in the hydraulic pump reaches a first ratio of the stored pressure, the brake is controlled to open; and when the last hoisting action is lowering, When the pressure in the hydraulic pump reaches a second ratio of the stored pressure, the control controls the brake to open, and the first ratio is less than or equal to the second ratio.

Wherein, when controlling the opening of the brake, the direction of the hoisting action can also be considered. Wherein, when the last hoisting action is lifting and the hoisting action is lifting, when the pressure in the hydraulic pump reaches a third ratio of the stored pressure, the brake is controlled to open; When the lifting is performed and the hoisting action is lowering, when the pressure in the hydraulic pump reaches the fourth ratio of the stored pressure, the brake is controlled to be opened; the last hoisting action is decentralized and the volume is When the lifting action is lowered, when the pressure in the hydraulic pump reaches the stored Controlling the brake to open when the fifth ratio of pressure is; and when the last hoisting action is lowering and the hoisting action is lifting, when the pressure in the hydraulic pump reaches the sixth ratio of the stored pressure And controlling the brake to be opened, the fourth ratio is smaller than the third ratio and the fifth ratio, and the third ratio fifth ratio is smaller than the sixth ratio.

Wherein, the third ratio and the fifth ratio may be 50-90%, the fourth ratio may be 30-70%, and the sixth ratio may be greater than or equal to 70% and less than 100%. Experiments have shown that when the third ratio and the fifth ratio are 60-80%, the fourth ratio is 40-60%, and the sixth ratio is greater than or equal to 80% and less than 100%, it is better Take into account the stability of the load lifting or lowering, the speed of the control device and the loss of the hydraulic pump due to excessive hydraulic pressure. More preferably, the third ratio and the fifth ratio are 70%, the fourth ratio is 50%, and the sixth ratio is 90%.

Figure 3 is a flow chart of the control method of the closed hydraulic hoisting circuit of the crane. The control method of the closed hydraulic hoisting circuit of the crane of the present invention will be described in detail below with reference to FIG.

First, the user can operate the joystick 500 to give a request to perform the hoisting action and the direction of the hoisting action. Thereafter, the controller 100 inputs a small current that can increase the pressure in the hydraulic pump to the proportional solenoid valve 300 located on the hydraulic pump, so that the proportional solenoid valve 300 is partially opened, and the pressure in the hydraulic pump is rapidly increased. At the same time, the real-time pressure in the hydraulic pump is detected by the pressure sensor 200, and when the real-time pressure reaches a ratio of the pressure stored in the controller 100 (the ratio can be determined by the direction of the previous and the hoisting action), the switch The solenoid valve 400 outputs a switching amount signal to open the switch solenoid valve 400 located on the brake, thereby opening the brake. Thereafter, the controller 100 outputs a corresponding current to the proportional solenoid valve 300 in accordance with the direction of the hoisting action given by the joystick 500 to perform the hoisting action. After the completion of the hoisting operation, the controller 100 stores the pressure in the hydraulic pump detected by the pressure sensor 200 at this time, and closes the switch solenoid valve 400, thereby closing the brake. When performing the next hoisting action, the controller 100 can control the opening of the brake according to the re-stored pressure and the direction of the next hoisting action. It should be noted that the crane lifts or depresses a load for the first time. Time, need to be given An initial pressure (i.e., "pressure signal input" step in Figure 3) because the pressure stored in controller 100 at this time does not apply to the load.

The present invention aims to reduce the pressure threshold for opening the brake by reducing the direction of the last hoisting action, reducing the time for establishing the pressure in the hydraulic pump, reducing the wear on the hydraulic pump, and ensuring the stability of the load lifting or lowering. In addition, since the brake is opened only when the pressure in the hydraulic pump reaches a certain proportion of the stored pressure, the hydraulic pump can ensure that the pressure can be established, thereby ensuring that the weight does not fall uncontrollably.

The preferred embodiments of the present invention have been described in detail above with reference to the accompanying drawings. However, the present invention is not limited to the specific details of the above embodiments, and various simple modifications of the technical solutions of the present invention may be made within the scope of the technical idea of the present invention. These simple variations are within the scope of the invention.

It should be further noted that the specific technical features described in the above specific embodiments may be combined in any suitable manner without contradiction.

In addition, any combination of various embodiments of the invention may be made, as long as it does not deviate from the idea of the invention, and should also be regarded as the disclosure of the invention.

Claims

Rights request

A control device for a closed hydraulic hoisting circuit of a crane, the closed hydraulic hoisting circuit of the crane comprising a hydraulic pump and a brake, wherein the control device stores the brake closed every time a hoisting operation is performed When the pressure in the hydraulic pump and the direction of the hoisting operation are performed, and when the hoisting operation is performed, the brake is controlled to be opened according to the stored pressure and the direction of the previous hoisting operation.

2. The control device according to claim 1, wherein

When the last hoisting action is lifting, the control device controls the brake to be opened when the pressure in the hydraulic pump reaches a first ratio of the stored pressure;

When the last hoisting action is a lowering, the control device controls the brake to open when the pressure in the hydraulic pump reaches a second ratio of the stored pressure.

The first ratio is greater than or equal to 30% and less than 100%, and the second ratio is greater than or equal to 50% and less than 100%.

The control device according to claim 2, wherein the first ratio is 60-80%, and the second ratio is greater than or equal to 80% and less than 100%.

The control device according to claim 3, wherein the first ratio is 70% and the second ratio is 90%.

The control device according to claim 1, wherein the control device controls the brake to be opened according to the direction of the hoisting operation when the brake is controlled to be opened.

6. The control device according to claim 5, wherein the control device is based on the following Slightly control the brake to open:

When the last hoisting action is lifting and the hoisting action is lifting, when the pressure in the hydraulic pump reaches a third ratio of the stored pressure, the brake is controlled to open;

When the last hoisting action is lifting and the hoisting action is lowering, when the pressure in the hydraulic pump reaches the fourth ratio of the stored pressure, the brake is controlled to be opened;

When the last hoisting action is lowering and the hoisting action is lowering, the brake is controlled to open when the pressure in the hydraulic pump reaches a fifth ratio of the stored pressure;

When the last hoisting action is lowering and the hoisting action is lifting, when the pressure in the hydraulic pump reaches the sixth ratio of the stored pressure, the brake is controlled to open.

The third and fifth ratios are 50-90%, the fourth ratio is 30-70%, and the sixth ratio is greater than or equal to 70% and less than 100%.

7. The control device according to claim 6, wherein the third ratio and the fifth ratio are 60-80%, the fourth ratio is 40-60%, and the sixth ratio is greater than or equal to 80% And less than 100%

The control device according to claim 7, wherein the third ratio and the fifth ratio are 70%, the fourth ratio is 50%, and the sixth ratio is 90%.

9. A method of controlling a closed hydraulic hoisting circuit of a crane, the closed hydraulic winding circuit of the crane comprising a hydraulic pump and a brake, the method comprising:

Each time the hoisting operation is performed, the pressure in the hydraulic pump when the brake is closed and the direction of the hoisting action are stored, and when the hoisting action is performed, according to the stored pressure and the last hoisting action The direction of the brake is controlled to open.

10. The control method according to claim 9, wherein When the last hoisting action is lifting, controlling the brake to open when the pressure in the hydraulic pump reaches a first ratio of the stored pressure;

When the last hoisting action is lowering, when the pressure in the hydraulic pump reaches a second ratio of the stored pressure, the control controls the brake to open,

11. The method according to claim 10, wherein the first ratio is 60-80%, and the second ratio is greater than or equal to 80% and less than 100%.

The control method according to claim 11, wherein the first ratio is 70% and the second ratio is 90%.

13. The control method according to claim 9, wherein the brake is controlled to be turned on according to the direction of the hoisting action when the brake is controlled to be opened.

14. The control method according to claim 13, wherein

The third ratio and the fifth ratio are 50-90%, and the fourth ratio is 30-70%, the first The six ratio is greater than or equal to 70% and less than 100%.

The control method according to claim 14, wherein the third ratio and the fifth ratio are 60-80%, the fourth ratio is 40-60%, and the sixth ratio is greater than or equal to 80% And less than 100%

The control method according to claim 15, wherein the third ratio and the fifth ratio are 70%, the fourth ratio is 50%, and the sixth ratio is 90%.