WO2014063490A1

WO2014063490A1 - Hydraulic system for controlling boom to rotate and control method therefor and concrete pumping equipment

Info

Publication number: WO2014063490A1
Application number: PCT/CN2013/076467
Authority: WO
Inventors: 秦晓峰; 刘如意; 李剑
Original assignee: 中联重科股份有限公司; 湖南中联重科智能技术有限公司
Priority date: 2012-10-26
Filing date: 2013-05-30
Publication date: 2014-05-01
Also published as: CN103122894B; CN103122894A

Abstract

Disclosed are a hydraulic system for controlling a boom to rotate and a control method therefor and concrete pumping equipment using the hydraulic system, wherein the hydraulic system comprises a hydraulic motor (1), a primary valve (2), a hydraulic pump (3), an oil tank (4), a controller (5) and a detecting device (6); when the primary valve (2) controls the hydraulic motor (1) to rotate, an oil inlet circuit of the hydraulic motor (1) is in communication with the hydraulic pump (2), and an oil return circuit is in communication with the oil tank (4); and when the primary valve (2) controls the hydraulic motor (1) to come to a stop, both the oil inlet circuit and the oil return circuit are locked, so the detecting device (6) can detect the value of the pressure in the oil return circuit, and the controller (5) can control the opening degree of the primary valve (2) according to the value of the pressure, such that the oil return circuit can be in communication with the oil tank again, the pressure is not accumulating in the oil return circuit, and therefore the rebound phenomenon that occurs when the boom is stopped can be prevented.

Description

Hydraulic system for controlling boom rotation, control method thereof and concrete pumping device

Technical field

The present invention relates to the field of hydraulic control of boom reversal, and more particularly to a hydraulic system for controlling boom reversal, a control method, and a concrete pumping apparatus using the same. Background technique

In various construction machines, boom reversing conditions, such as concrete pump trucks in concrete pumping equipment, or tire cranes, etc., are often used. Among them, the concrete pump truck is a modern construction equipment used for continuous pouring of concrete. It has the advantages of flexibility, high construction efficiency, good construction quality and low environmental pollution. It is widely used in modern building construction. In concrete pump trucks, the point of the cloth can be easily changed by the luffing or turning of the boom, where the rotation of the boom is usually driven by a hydraulic motor. Since the concrete pump truck boom has a large weight and a long arm, its large moment of inertia makes it difficult to accurately control the boom return. Especially during the swinging action of the concrete pump truck boom, the stability of the return brake directly affects the positioning and operation safety of the cloth point.

Specifically, since the moment of inertia of the pump boom is large, even if the hydraulic system controls the hydraulic motor to stop, the boom is still rotating. This causes the pressure of the hydraulic swing motor to enter the oil passage to decrease and the return passage pressure to increase. This trend continues for a period of time after the boom stops clockwise. At this time, the oil return route of the hydraulic swing motor is compressed, so that the oil can not flow out and is compressed to accumulate a higher pressure. For example, the pressure causes the hydraulic motor to rotate counterclockwise in the opposite direction after the boom stops the pointer rotation. Therefore, the hydraulic motor will drive the boom to rotate counterclockwise. The counterclockwise rotation of the boom will also pass the "counterclockwise rotation - stop - clockwise rotation" process. This reciprocates until the return rotation of the concrete boom is consumed in the form of heat. The concrete pump truck boom is rotating counterclockwise. Therefore, this method in the prior art will cause the concrete pump truck boom to stop when it is stopped. The reversal phenomenon, that is, the rebound phenomenon, is accompanied by multiple reciprocating oscillations. This poses a major hidden danger to the positioning and operation safety of the concrete pump truck. Summary of the invention

SUMMARY OF THE INVENTION An object of the present invention is to provide a hydraulic system for controlling the swing of a boom which is capable of not rebounding after the boom starts to stop, so that the positioning accuracy and safety of the boom are high.

Another object of the present invention is to provide a concrete pumping apparatus that controls the rotation of the boom using the hydraulic system that controls the swing of the boom provided by the present invention.

It is still another object of the present invention to provide a control method for a hydraulic system for controlling the swing of a boom, which can prevent the boom from rebounding after starting to stop, thereby making the positioning accuracy and safety of the boom high.

In order to achieve the above object, the present invention provides a hydraulic system for controlling the swing of a boom, comprising a hydraulic motor that drives the boom to rotate, a main valve that controls the rotation and stop of the hydraulic motor, and a hydraulic pump and a fuel tank that communicate with the main valve. When the main valve controls the hydraulic motor to rotate, the oil inlet path of the hydraulic motor is in communication with the hydraulic pump, and the return oil passage is in communication with the oil tank, when the main valve controls the hydraulic motor to start to stop rotating The oil inlet circuit and the return oil circuit are both locked, wherein the hydraulic system includes a controller and a detecting device electrically connected to each other, and after the main valve controls the hydraulic motor to start to stop, the detecting device A pressure value of a return line of the hydraulic motor can be detected, and the controller controls an opening degree of the main valve according to the pressure value to communicate the return path with the oil tank.

Preferably, the hydraulic system includes a database electrically connected to the controller, wherein the database has a main valve opening value corresponding to the pressure value, and the controller is opened according to a main valve matching the pressure value. The degree of control controls the opening of the main valve.

Preferably, a balance valve is disposed between the hydraulic motor and the main valve, and the balance valve locks the oil inlet passage and the return oil passage after the hydraulic motor is stopped.

Preferably, the main valve is an electro-hydraulic proportional directional control valve Preferably, the hydraulic motor includes a first oil passage and a second oil passage that communicate with a working oil port of the main valve, and the main valve is a three-position electromagnetic reversing valve, and the three-position electromagnetic reversing valve In the middle position, the hydraulic motor stops, the first oil passage and the second oil passage are locked, and in the right position of the three-position electromagnetic reversing valve, the hydraulic motor rotates forward, the first The oil passage is the oil inlet passage, the second oil passage is the oil return passage, the hydraulic motor is reversed in a left position of the three-position electromagnetic reversing valve, and the first oil passage is the Returning to the oil passage, the second oil passage is the oil inlet passage.

Preferably, the balancing valve includes a first balancing module and a second balancing module, the first balancing module is serially connected to the first oil path, and includes a first sequential valve and a first one-way valve connected in parallel with each other. The second balancing module is serially connected to the second oil passage, and includes a second sequential valve and a second one-way valve connected in parallel with each other, the first one-way valve and the second one-way valve are only allowed to oil The liquid flows to the hydraulic motor, and a control port of the first sequence valve is in communication with the first oil passage, and a control port of the second sequence valve is in communication with the second port.

Preferably, the detecting device comprises a first pressure sensor for detecting a pressure value of the first oil passage, and a second pressure sensor for detecting the second pressure sensor The pressure value of the oil circuit.

Preferably, the main valve is a three-position six-electric liquid proportional directional control valve, and includes a first oil inlet port, a second oil inlet port, an oil outlet port, a first working oil port, a second working oil port and a third a working oil port, the first oil inlet port and the second oil inlet port are both connected to the hydraulic pump, the oil return port is in communication with the oil tank, and the first working oil port is connected to the oil tank, the first The working port is in communication with the first oil passage, the third working port is in communication with the second oil passage, in the middle of the main valve, the first oil inlet and the first The working oil port is connected, the second oil inlet port is closed, the oil return port is connected to the second working oil port and the third working oil port; in the right position of the main valve, the first oil inlet port And the first working oil port is cut off, the second oil inlet port is in communication with the second working oil port, the oil return port is connected to the third working oil port; on the left side of the main valve Positioned, the first oil inlet and the first working oil port are both closed, and the second oil inlet is connected to the third working oil port, the back Mouth and The second working oil port is connected.

According to another aspect of the present invention, there is also provided a concrete pumping apparatus comprising a boom controlled by a hydraulic system, the hydraulic system being the hydraulic system for controlling the swing of the boom provided by the present invention.

Preferably, the concrete pumping device is a concrete pump truck.

According to still another aspect of the present invention, a control method of a hydraulic system for controlling a swing of a boom is provided, wherein the hydraulic system is a hydraulic system provided by the present invention, wherein the control method includes a stop step, a detecting step, and a control step; in the stalling step, controlling the main valve to lock the oil inlet passage and the return oil passage, thereby controlling the hydraulic motor to start to stop; in the detecting step, in the detecting step After the hydraulic motor starts to stop, detecting the pressure value of the oil return passage by using the detecting device; in the controlling step, the controller controls the opening degree of the main valve according to the pressure value to open The oil return passage connects the oil return passage and the oil tank; repeating the detecting step and the controlling step until the hydraulic motor is completely stopped.

Preferably, the main valve is a three-position electromagnetic reversing valve, and in the middle position of the main valve, the oil inlet path and the return oil path are locked, and in the right position of the main valve, the hydraulic motor rotates forward. In the left position of the main valve, the hydraulic motor is reversed, and when the hydraulic motor is required to change from positive to stop, in the stalling step, the main valve is correspondingly switched from the right position to the right a middle position, in the controlling step, controlling the main valve to maintain a corresponding opening degree in the right position according to the pressure value of the return oil passage; when the hydraulic motor is required to change from reverse rotation to stop rotation, In the stalling step, the main valve is correspondingly switched from the left position to the neutral position, and in the controlling step, controlling the main valve to maintain a corresponding opening degree in the left position according to the pressure value of the return oil passage .

According to the above technical solution, in the hydraulic system and the control method thereof provided by the present invention, after the boom is required to start to stop, firstly, the oil inlet and the oil return can be locked, and then the main pressure is controlled according to the pressure change of the return passage. The opening degree of the valve, so that the return oil passage can be reconnected with the oil tank, so that the return oil passage does not accumulate the pressure, thereby avoiding the rebound phenomenon after the boom is stopped, and providing the positioning accuracy of the boom And security.

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

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

1 is a schematic structural view of a hydraulic system according to a preferred embodiment of the present invention, wherein a main valve is at a neutral position;

2 is a schematic structural view of a hydraulic system according to a preferred embodiment of the present invention, wherein the main valve is located in the right position;

3 is a schematic structural view of a hydraulic system provided by a preferred embodiment of the present invention, wherein the main valve is located at the left position.

Description of the reference numerals

1 hydraulic motor 2 main valve

3 hydraulic pump 4 fuel tank

5 controller 6 detection device

7 balancing valve 8 database

71 First Balance Module 72 Second Balance Module

71a first sequence valve 72a second sequence valve

71b first check valve 72b second check valve

a first oil circuit b second oil circuit

PI first inlet P2 second inlet

T return port A first working port

B second working port C third working port detailed description

In the present invention, the concrete pump truck in the concrete pumping device provided by the present invention is taken as an example to introduce the hydraulic system for controlling the swing of the boom provided by the present invention. It should be noted that the concrete pump truck is only one of the present invention. A preferred embodiment, other fields that can be used for boom slewing control, such as a crane, can also be applied to the hydraulic system provided by the present invention. The present invention is not limited to the deformation of such an application field, and should also fall within the scope of the present invention. In the scope of protection.

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.

As shown in FIGS. 1 to 3, the present invention provides a hydraulic system for controlling the swing of a boom, comprising a hydraulic motor that drives the swing of the boom, a main valve 2 that controls the rotation and stop of the hydraulic motor 1, and a main valve 2 with the main valve 2 The hydraulic pump 3 and the fuel tank 4 are connected. When the main valve 2 controls the hydraulic motor 1 to rotate, the oil inlet circuit of the hydraulic motor 1 communicates with the hydraulic pump 3, and the return oil passage communicates with the oil tank 4, when the main valve 2 controls the hydraulic motor to start 1 stop. After that, both the oil inlet and the return road are locked. Among them, there are various ways to lock the oil inlet and return oil passages, for example, can be locked by a type 0 M-type intermediate function reversing valve with a pressure maintaining function. In the oil passage, in order to prevent accidents when controlling a large object such as a boom, the oil passage is locked in the field by a balance valve. In the preferred mode of the invention, the balance valve 7 is also used to lock the oil passage. Dead, the locking principle of the balancing valve will be described below with reference to the drawings.

Since the return line is locked after the hydraulic motor 1 is stopped, as the background art says, because the inertia of the boom is large, the return flow of the hydraulic motor 1 will accumulate pressure, thereby causing the boom to rebound or even The vibration is reciprocated, so that the safety of the construction machine such as the concrete pump truck using the oil system and the accuracy of the boom positioning are disturbed. In order to solve this problem, the present invention provides a hydraulic system including a controller 5 and a detecting device 6 electrically connected to each other, wherein after the main valve 2 controls the hydraulic motor 1 to start to stop, that is, before the hydraulic motor 1 is completely stopped, The detecting device 6 is capable of detecting the pressure value of the oil return path b of the hydraulic motor 1, and the controller 5 controls the opening degree of the main valve 2 based on the pressure value. From According to the change of the pressure value of the oil return road b, the locked oil return passage is again connected with the oil tank, so that the return oil passage does not accumulate the pressure, gP, the inertia of the boom can be released, thereby effectively solving the arm. The problem of rebounding.

Furthermore, the present invention also provides a control method using the hydraulic system provided by the present invention, wherein the control method includes a stalling step, a detecting step, and a controlling step; in the stopping step, controlling the main valve to lock the inlet An oil passage and the returning oil passage, thereby controlling the hydraulic motor to start to stop, specifically, switching the main valve from the working position to the non-working position, thereby causing the oil inlet passage communicating with the hydraulic pump 3 and communicating with the oil tank 4 The return line is locked. At this time, the hydraulic motor starts to stop, but due to the inertia of the boom, pressure is accumulated on the returning oil path, and if it is not processed, the reciprocating motion of the boom is caused, that is, the problems in the prior art occur.

Therefore, in the detecting step in the control method provided by the present invention, after the hydraulic motor starts to stop, the pressure value of the return path can be detected using the detecting device; and in the controlling step, the controller can control the main valve according to the pressure value. The opening degree is opened to open the return line, so that the return line and the fuel tank 4 are again connected; at this time, during the stop of the hydraulic motor, the pressure is not accumulated in the return line, so the pressure of the return line becomes small. Then, the above detecting step and the controlling step are repeated, that is, the controller controls the opening degree of the main valve 2 with the opening value matched with the new reduced pressure value, and the pressure value of the returning oil path is completed with the stop of the hydraulic motor Gradually becoming small, the opening of the main valve is also gradually reduced, so that when the opening value of the main valve is zero, the hydraulic motor is completely stopped.

Therefore, in the above-described control method provided by the present invention, it is possible to ensure that the pressure does not accumulate during the process from the start of the hydraulic motor to the complete stop. Therefore, the positioning accuracy and safety of the boom can be made high.

It should be noted that there are various embodiments that can implement the above technical solutions, such as the structure of the main valve, and the specific manner of controlling the hydraulic motor, etc. For the convenience of description, only the preferred embodiments thereof will be described herein. The mode is only for illustrating the invention and is not intended to limit the invention.

As shown in Figures 1 to 3, in a preferred embodiment of the present invention, the hydraulic system includes and controls The database 5 is electrically connected to the database 8, in which the main valve opening value corresponding to the pressure value is described, and the controller 5 controls the opening degree of the main valve 2 based on the main valve opening value matching the pressure value. Gp, it is necessary to carry out multiple tests for different types of booms, and find the main valve opening value which can match the return line pressure value in the case where the technical problem of the present invention can be solved. Specifically, the detecting device 6 can detect the pressure value of the returning oil path in real time and feed back the returning oil pressure value to the controller 5, and the controller 5 can set different pressure value extraction frequencies, and the principle is that the higher the extraction frequency is, the set main The greater the valve opening value, the higher the control accuracy. This manner can be obtained by a person skilled in the art through numerous trials and operational experience, and the present invention will not be described in detail herein. In addition, in order to achieve precise control of the opening degree of the main valve 2, the main valve 2 is preferably an electro-hydraulic proportional valve reversing valve, that is, the controller 5 can control the current of the proportional electromagnet of the main valve 2 to realize the main valve 2 proportional control. Of course, in other embodiments not mentioned, it can also be implemented by a common solenoid valve, but it is necessary to frequently control the opening and closing of the common solenoid valve and precisely control the length of the opening and closing time to achieve the object of the present invention. It falls within the scope of protection of the present invention.

As described above, in the preferred embodiment of the present invention, the balance valve 7 is used to lock the intake and return lines, that is, preferably, the balance valve 7 is provided between the hydraulic motor 1 and the main valve 2, in the hydraulic pressure After the motor 1 stops, the balancing valve 7 locks the oil inlet and return lines. Wherein, the balancing valve can be any type of balancing valve in the field, and the structure and principle of the invention are not limited, and the use of various balancing valves should fall within the protection scope of the present invention.

In a preferred embodiment of the present invention, the hydraulic system provided by the present invention is capable of controlling the hydraulic motor to achieve forward rotation and reverse rotation. Referring to the direction in the drawings, the forward rotation refers to the hydraulic motor 1 rotating clockwise, but Turning refers to the hydraulic motor 1 rotating counterclockwise. Specifically, the function of switching the oil passage and the return oil passage by the main valve can be realized. Wherein, the hydraulic motor 1 includes a first oil passage a and a second oil passage b that communicate with the working oil port of the main valve 3, and the main valve 2 is a three-position electromagnetic reversing valve, and the middle position of the three-position electromagnetic reversing valve The hydraulic motor 1 stops, and the first oil passage a and the second oil passage b are locked. In the right position of the three-position electromagnetic reversing valve, the hydraulic motor 1 rotates forward, and the first oil passage a is an intake passage. The second oil circuit b is back The oil passage; in the left position of the three-position electromagnetic reversing valve, the hydraulic motor 1 is reversed, the first oil passage a is the return oil passage, and the second oil passage b is the intake oil passage. In this embodiment, the working process is: when the hydraulic motor is required to change from positive to stop, in the stalling step, the main valve is correspondingly switched from the right position to the neutral position, in the control step, according to the return path The pressure value controls the main valve to maintain a corresponding opening degree in the right position to communicate with the return line and the fuel tank; when the hydraulic motor is required to change from reverse to stop, in the stop step, the main valve is switched from the left position accordingly To the neutral position, in the control step, according to the pressure value of the return line, the control main valve maintains the corresponding opening degree in the left position to communicate with the oil return and the fuel tank.

Based on this, the balancing valve 7 can include two balancing modules respectively connected in series on the first oil passage a and the second oil passage b, and the two balancing modules can lock the corresponding oil passages, and it should be noted that the present invention The balancing valve used in the integration of two balancing modules in one valve member can also be independently provided as a valve member in other modes not mentioned. Such deformations can also fall within the scope of the invention. Specifically, the balance valve 7 provided by the present invention includes a first balance module 71 and a second balance module 72. The first balance module 71 is serially connected to the first oil passage a, and includes a first sequence valve 71a and a parallel connection with each other. The first check valve 71b, the second balance module 72 is serially connected to the second oil passage b, and includes a second sequence valve 72a and a second check valve 71b, which are connected in parallel with each other, the first check valve 71b and the second single The valve 72b allows only the oil to flow to the hydraulic motor, the control port of the first sequence valve 71a communicates with the first oil passage a, and the control port of the second sequence valve 72a communicates with the second port b.

Therefore, when the inlet passage has pressurized oil, the sequence valve capable of controlling the return passage is opened, so that the return passage can communicate with the tank 4, so that the hydraulic motor rotates, and when the main valve 2 is at the neutral position, That is, after the hydraulic motor stops, if there is no pressure oil in the oil inlet, the sequence valve of the return oil circuit does not open, and the oil return path is locked by the one-way valve. Since the balance module is provided in both the first oil passage a and the second oil passage b, the hydraulic motor 1 can be locked by the balancing valve 7 regardless of whether the hydraulic motor 1 returns from the forward rotation state or the reverse rotation state to the stall state. Further, in order to achieve the object of the present invention in both the forward rotation and the reverse rotation state, that is, when the first oil passage a and the second oil passage b are respectively used as the oil return passage, the pressure value can be detected, which is preferred in the present invention. In an embodiment, the detecting device 6 comprises a first pressure sensor 61 and a second pressure sensor 62, the first pressure sensor 61 is for detecting the pressure value of the first oil passage a, and the second pressure sensor 62 is for detecting the pressure value of the second oil passage b. The specific working process will be described below with reference to the drawings and the working state of the main valve.

Preferably, the main valve 2 is a three-position six-electrolyte proportional directional control valve, and includes a first oil inlet port P1, a second oil inlet port P2, an oil outlet port T, a first working oil port Α, a second working The oil port Β and the third working port C, the first oil inlet port P1 and the second oil inlet port Ρ2 are both connected to the hydraulic pump 3, the oil return port 连通 is in communication with the oil tank 4, and the first working oil port Α is connected to the oil tank 4 The second working port B is in communication with the first oil passage a, and the third working port C is in communication with the second oil passage b.

As shown in FIG. 1, in the middle position of the main valve 2, the first oil inlet port P1 is in communication with the first working oil port A, the second oil inlet port P2 is closed, the oil return port T and the second working port B and the first The three working ports C are all connected; that is, the hydraulic pump 3 and the oil tank 4 are in communication at this time, so that neither the first oil passage a and the second oil passage b flow into the pressure oil, and under the action of the balancing valve 7, Both the oil passage a and the second oil passage b are locked, that is, the hydraulic motor can be locked, and the hydraulic motor can be prevented from being free from slipping and the like.

As shown in FIG. 2, in the right position of the main valve 2, the first oil inlet P1 and the first working oil port are both closed, the second oil inlet port P2 is connected with the second working oil port B, and the oil return port T and The third working port C is connected; that is, the working oil of the hydraulic pump 3 can be supplied to the first oil passage a through the second oil inlet port P2 and the second working oil port B, and the working oil passes through the first of the balancing valve 7 at this time. The first check valve 71b of the balancing module 71 flows into the hydraulic motor 1, at which time the first oil passage a serves as an oil inlet passage and the second oil passage b serves as a return oil passage, and thus the second sequence valve of the second balancing module 72 72a can be opened, that is, the second oil passage b is communicated with the oil tank 4 through the third working oil port C and the oil return port T. At this time, the clockwise rotation of the hydraulic motor 1 can be realized, that is, forward rotation.

At this time, if the forward rotation of the hydraulic motor 1 is to be stopped, after the second oil passage b is locked, the pressure of the second oil passage, that is, the return passage, is detected by the second pressure sensor 62, thereby according to the second oil passage b. The pressure value controls the opening degree of the main valve 2 such that the second oil passage b is again in communication with the oil tank 4 until the hydraulic motor 1 is completely stopped. Therefore, no pressure is accumulated in the second oil passage b to prevent the hydraulic motor The boom rebounded after stopping.

Similarly, as shown in FIG. 3, in the left position of the main valve 2, the first oil inlet port P1 and the first working oil port A are both closed, and the second oil inlet port P2 is connected with the third working oil port C, and the oil return port is connected. T is in communication with the second working port B. That is, the working oil of the hydraulic pump 3 can be supplied to the second oil passage b through the second oil inlet port P2 and the third working oil port C, and the working oil passes through the first one-way of the second balancing module 72 of the balancing valve 7 at this time. The valve 72b flows into the hydraulic motor 1, at which time the second oil passage b serves as an oil inlet passage, and the first oil passage a serves as a return oil passage, so that the first sequence valve 71a of the first balancing module 71 can be opened, that is, the first The oil passage a communicates with the oil tank 4 through the second working port B and the oil return port T. At this time, the counterclockwise rotation of the hydraulic motor 1 can be realized, that is, reverse rotation. At this time, if the reverse rotation of the hydraulic motor 1 is to be stopped, after the first oil passage a is locked, the pressure of the first oil passage a, that is, the return passage, is detected by the first pressure sensor 61, thereby according to the first oil passage a The pressure value controls the opening degree of the main valve 2 such that the first oil passage a is again in communication with the oil tank 4 until the hydraulic motor 1 is completely stopped. Therefore, no pressure is accumulated in the first oil passage a to prevent the boom from rebounding after the hydraulic motor is stopped.

The above working process is only the working process in the preferred embodiment of the present invention as shown in the figure, wherein the main valve 3 can be of various other types, and the three positions of the M or Y type median function can also be used. A four-way reversing valve or the like which can be conceived by those skilled in the art, as long as the above-described object of the present invention and the above-described working processes can be achieved, are all within the scope of the present invention.

In summary, the hydraulic system provided by the present invention can control the opening degree of the main valve according to the pressure value of the returning oil path, so that the returning oil circuit can communicate with the oil tank again after being locked, and thus the hydraulic motor 1 starts to stop. After that, it will not accumulate pressure in the return road, overcoming the problem of bounce of the boom. Moreover, the concrete pumping equipment provided by the present invention, especially the boom of the concrete pump truck, has high precision and safety. Therefore, the hydraulic system and the control method for controlling the swing of the boom and the concrete pumping device using the hydraulic system provided by the invention have high practicability and popularization value.

The preferred embodiments of the present invention have been described in detail above with reference to the drawings, but the present invention is not limited to the specific details of the embodiments described above, and the present invention can be applied to the present invention within the scope of the technical idea of the present invention. The technical solution carries out a variety of simple variants, all of which 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 order to avoid unnecessary repetition, the present invention has various possibilities. The combination method will not be described separately.

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

1. A hydraulic system for controlling the swing of a boom, comprising a hydraulic motor (1) for driving the boom to rotate, a main valve (2) for controlling the rotation and stop of the hydraulic motor (1), and a main valve (2) communicating with the main valve (2) a hydraulic pump (3) and a fuel tank (4), when the main valve (2) controls the hydraulic motor (1) to rotate, the oil feed path of the hydraulic motor (1) is connected to the hydraulic pump (3) The oil return passage is connected to the oil tank (4), and when the main valve (2) controls the hydraulic motor (1) to start to stop, the oil inlet passage and the return oil passage are locked, and the characteristic is that ,

The hydraulic system includes a controller (5) and a detecting device (6) electrically connected to each other, and after the main valve (3) controls the hydraulic motor (4) to start to stop, the detecting device (6) can Detecting a pressure value of a return line of the hydraulic motor (4), the controller (5) controlling an opening degree of the main valve (3) according to the pressure value, so that the return line and the oil tank Connected.

2. The hydraulic system according to claim 1, wherein the hydraulic system comprises a database (8) electrically connected to the controller (5), wherein the database (8) is associated with the pressure value The main valve opening value, the controller (5) controls the opening degree of the main valve (3) according to a main valve opening value matching the pressure value.

3. Hydraulic system according to claim 1 or 2, characterized in that a balancing valve (7) is arranged between the hydraulic motor (1) and the main valve (2), in which the hydraulic motor (1) After the stall, the balancing valve (7) locks the oil inlet passage and the return oil passage.

4. The hydraulic system according to claim 1, wherein the main valve (2) is an electro-hydraulic proportional directional control valve.

The hydraulic system according to claim 3, characterized in that the hydraulic motor (1) comprises a first oil passage (a) and a second oil passage that communicate with a working oil port of the main valve (3) (b), The main valve (2) is a three-position electromagnetic reversing valve. In the middle of the three-position electromagnetic reversing valve, the hydraulic motor (1) stops, the first oil passage (a) and the first The two oil passages (b) are all locked. In the right position of the three-position electromagnetic reversing valve, the hydraulic motor (1) rotates forward, and the first oil passage (a) is the oil inlet passage, The second oil passage (b) is the return oil passage, and in the left position of the three-position electromagnetic reversing valve, the hydraulic motor (1) is reversed, and the first oil passage (a) is the return oil The second oil passage (b) is the oil inlet passage.

6. The hydraulic system according to claim 5, wherein the balancing valve (7) comprises a first balancing module (71) and a second balancing module (72), the first balancing module (71) being connected in series On the first oil passage (a), and including a first sequence valve (71a) and a first one-way valve (71b) connected in parallel with each other, the second balancing module (72) is serially connected to the second On the oil passage (b), and including a second sequence valve (72a) and a second check valve (71b) connected in parallel with each other, the first check valve (71b) and the second check valve (72b) Only the oil is allowed to flow to the hydraulic motor, the control port of the first sequence valve (71a) is in communication with the first oil passage (a), and the control port of the second sequence valve (72a) is The second port (b) is in communication.

7. The hydraulic system according to claim 5, wherein said detecting means (6) comprises a first pressure sensor (61) and a second pressure sensor (62), said first pressure sensor

(61) for detecting a pressure value of the first oil passage (a), and the second pressure sensor (62) for detecting a pressure value of the second oil passage (b).

8. The hydraulic system according to claim 3, wherein the main valve (2) is a three-position six-electric liquid proportional directional control valve, and includes a first oil inlet port (P1) and a second oil inlet port. (P2), oil outlet (T), first working port (Α), second working port (Β) and third working port (C), the first oil inlet (P1) and the first The two inlet ports (Ρ2) are connected to the hydraulic pump (3), the oil return port (Τ) is in communication with the oil tank (4), the first working oil port (Α) and the oil tank (4) Connected, the second working oil port (B) is in communication with the first oil passage (a), and the third working oil port (C) is in communication with the second oil passage (a);

In a middle position of the main valve (2), the first oil inlet (P1) is in communication with the first working port (A), and the second oil inlet (P2) is closed, the back The oil port (T) is connected to the second working port (B) and the third working port (C);

In the right position of the main valve (2), the first oil inlet (P1) and the first working oil port are both closed, the second oil inlet (P2) and the second working oil The port (B) is connected, and the oil return port (T) is in communication with the third working oil port (C);

In the left position of the main valve (2), the first oil inlet (P1) and the first working oil port are both closed, the second oil inlet (P2) and the third working oil The port (C) is connected, and the oil return port (T) is in communication with the second working oil port (B).

9. A concrete pumping apparatus comprising a boom controlled by a hydraulic system, wherein the hydraulic system is a hydraulic fluid for controlling the swing of the boom according to any one of claims 1-8. system.

10. The concrete pumping apparatus according to claim 9, wherein the concrete pumping device is a concrete pump truck. A control system for controlling a hydraulic system of a boom, wherein the hydraulic system is the hydraulic system according to any one of claims 1 to 4, wherein the control method comprises a stalling step, Detection steps and control steps;

In the stalling step, the main valve is controlled to lock the oil inlet passage and the return oil passage, thereby controlling the hydraulic motor to start to stop;

In the detecting step, after the hydraulic motor starts to stop, detecting the pressure value of the oil return path by using the detecting device; In the controlling step, the controller controls the opening degree of the main valve according to the pressure value to open the oil returning path to connect the oil returning passage and the oil tank;

The detecting step and the controlling step are repeated until the hydraulic motor is completely stopped. 12. The control method according to claim 11, wherein the main valve is a three-position electromagnetic reversing valve, and in the middle position of the main valve, the oil inlet passage and the return oil passage are locked. In the right position of the main valve, the hydraulic motor rotates forward, and in the left position of the main valve, the hydraulic motor reverses,

When the hydraulic motor is required to change from positive to stop,

In the stopping step, the main valve is correspondingly switched from the right position to the middle position, and in the controlling step, controlling the main valve to maintain the corresponding position in the right position according to the pressure value of the return oil path Opening degree; when the hydraulic motor is required to change from reverse to stop,

In the stalling step, the main valve is correspondingly switched from the left position to the neutral position, and in the controlling step, controlling the main valve to maintain the corresponding position in the left position according to the pressure value of the return line Opening degree.