Crane and its hydraulic control system

Abstract

The present disclosure provides a crane and a hydraulic control system thereof. The hydraulic control system includes: a hydraulic oil source; a slewing motor configured to drive the slewing of the crane's turntable; a counterweight cylinder configured to drive the crane's counterweight block to move up and down relative to the crane's turntable to hang the counterweight block on the turntable; a first control unit, including a flow regulating unit for regulating the flow of hydraulic oil at the first working port or the second working port, configured to regulate the flow direction of the hydraulic oil at the first working port A1 and the second working port B1 according to the control signal of the first control port to change the rotation direction of the slewing motor; and a second control unit, configured to regulate the flow direction of the hydraulic oil at the third working port A2 and the fourth working port B2 according to the control signal of the second control port to change the moving direction of the piston rod of the counterweight cylinder relative to the cylinder barrel. The present disclosure is conducive to improving the stability of the slewing speed of the turntable during the crane counterweight hanging process.

Description

Technical Field

[0001] The present disclosure relates to the field of engineering machinery, and in particular to a crane and a hydraulic control system thereof. Background Art

[0002] For jib cranes, such as truck cranes, the counterweight is set at the rear of the crane turntable. It is a counterweight device that enables the crane's upper structure to achieve torque balance when working. The crane's counterweight can be divided into fixed counterweights and mounted counterweights. The mounted counterweight consists of a counterweight cylinder and a counterweight block. When mounting the counterweight block, first place the counterweight block at the specified position of the frame; then operate the remote control device outside the crane's control room to control the turntable to rotate to a certain position, then control the piston rod of the counterweight cylinder to extend and allow the tray at the end of the piston rod of the counterweight cylinder to enter the counterweight block installation hole, and then control the piston rod of the counterweight cylinder to retract to complete the counterweight mounting.

[0003] In the control room of the crane, the slewing of the crane's turntable is usually controlled by an electric proportional handle. By adjusting the inclination angle of the electric proportional handle, the size of the control current can be changed, and then the size of the control valve opening and the flow input to the slewing motor can be changed, thereby changing the slewing speed of the turntable. However, for the above-mentioned counterweight attachment process, the control signal of the remote control device to control the slewing of the turntable is a constant current. Since the consistency of the electromagnet and valve stem of different slewing control valves is difficult to ensure, the output flow is different under the same control current, resulting in some cranes using remote control to attach the counterweight, the turntable has no slewing action or the slewing action is too fast, causing inconvenience to the commissioning or use of the crane. Summary of the invention

[0004] The purpose of the present disclosure is to provide a crane and a hydraulic control system thereof, so as to improve the stability of the rotation speed of a turntable during the crane counterweight attachment process.

[0005] A first aspect of the present disclosure provides a hydraulic control system for a crane, comprising:

[0006] Hydraulic oil source;

[0007] A slewing motor having a first working port and a second working port, and configured to drive the slewing table of the crane;

[0008] a counterweight cylinder having a first working port and a second working port, and configured to drive the counterweight of the crane to move up and down relative to the turntable of the crane so as to hang the counterweight on the turntable;

[0009] a first control unit having a first oil inlet port, a first oil return port, a first working port, a second working port and a first control port, wherein the first oil inlet port is connected to the hydraulic oil source, the first oil return port is connected to the oil return pipeline, the first working port is connected to the first working port of the swing motor, and the second working port is connected to the second working port of the swing motor, the first control unit comprises a flow regulating unit for regulating the flow of the hydraulic oil of the first working port or the second working port, and the first control unit is configured to regulate the flow direction of the hydraulic oil of the first working port and the second working port according to the control signal of the first control port so as to change the rotation direction of the swing motor; and

[0010] The second control unit has a second oil inlet port, a second oil return port, a third working port, a fourth working port and a second control port, the second oil inlet port is connected to the hydraulic oil source, the second oil return port is connected to the oil return pipeline, the third working port is connected to the first working port of the counterweight cylinder, and the fourth working port is connected to the second working port of the counterweight cylinder. The second control unit is configured to adjust the flow direction of the hydraulic oil in the third working port and the fourth working port according to the control signal of the second control port to change the moving direction of the piston rod of the counterweight cylinder relative to the cylinder barrel.

[0011] According to some embodiments of the present disclosure,

[0012] The first control unit comprises a first reversing valve, the first oil inlet port, the first oil return port, the first working port and the second working port of the first control unit are respectively connected to the oil inlet port, the oil return port, the first working port and the second working port of the first reversing valve, and the first control port is the control end of the first reversing valve; and / or

[0013] The second control unit includes a second reversing valve, and the second oil inlet port, the second oil return port, the third working port and the fourth working port of the second control unit are respectively connected to the oil inlet port, the oil return port, the first working port and the second working port of the second reversing valve, and the second working port is the control end of the second reversing valve.

[0014] According to some embodiments of the present disclosure, the flow regulating unit includes a speed regulating valve, an oil inlet of the speed regulating valve is connected to the first oil inlet port, and an oil outlet of the speed regulating valve is connected to the oil inlet of the first reversing valve.

[0015] According to some embodiments of the present disclosure, the first control unit also includes a first hydraulically controlled one-way valve and a second hydraulically controlled one-way valve, the oil inlet of the first hydraulically controlled one-way valve is connected to the first working port of the first reversing valve, the oil outlet of the first hydraulically controlled one-way valve is connected to the first working port, the hydraulic control port of the first hydraulically controlled one-way valve is connected to the second working port of the first reversing valve, the oil inlet of the second hydraulically controlled one-way valve is connected to the second working port of the first reversing valve, the oil outlet of the second hydraulically controlled one-way valve is connected to the second working port, and the hydraulic control port of the second hydraulically controlled one-way valve is connected to the first working port of the first reversing valve.

[0016] According to some embodiments of the present disclosure, the first control unit also includes a first double one-way valve arranged between the first working port and the first working port of the first reversing valve, and a second double one-way valve arranged between the second working port and the second working port of the first reversing valve, and the first double one-way valve and the second double one-way valve each include two parallel one-way valves with opposite conduction directions.

[0017] According to some embodiments of the present disclosure,

[0018] The first control unit further comprises a first one-way valve, an oil inlet of the first one-way valve is connected to an oil return port of the first reversing valve, and an oil outlet of the first one-way valve is connected to the first oil return port; and / or

[0019] The second control unit further includes a second one-way valve, an oil inlet of the second one-way valve is connected to an oil return port of the second reversing valve, and an oil outlet of the second one-way valve is connected to the second oil return port.

[0020] According to some embodiments of the present disclosure,

[0021] The hydraulic control system further includes a third control unit, the third control unit having a third oil inlet port, a third oil return port, a fifth working port, a sixth working port and a third control port, the third oil inlet port being connected to the hydraulic oil source, the third oil return port being connected to the oil return pipeline, the fifth working port being connected to the first working port of the swing motor, the sixth working port being connected to the second working port of the swing motor, the third control unit being configured to adjust the flow direction of the hydraulic oil of the fifth working port and the sixth working port according to the control signal of the third control port to change the rotation direction of the swing motor;

[0022] The hydraulic control system has a first control mode and a second control mode. In the first control mode, the hydraulic oil source is connected to the first oil inlet port and disconnected from the third oil inlet port, and the hydraulic oil source supplies oil to the swing motor through the first control unit. In the second control mode, the hydraulic oil source is connected to the third oil inlet port and disconnected from the first oil inlet port, and the hydraulic oil source supplies oil to the swing motor through the third control unit.

[0023] According to some embodiments of the present disclosure, the hydraulic control system further includes:

[0024] a remote control device connected to the first control port and the second control port by signals, the remote control device being configured to provide, in the first control mode, to the first control port a control signal for adjusting the working state of the first control unit to change the rotation direction of the swing motor, and to provide to the second control port a control signal for adjusting the working state of the second control unit to change the moving direction of the piston rod of the counterweight cylinder relative to the cylinder barrel; and

[0025] The control room control device is configured to provide a control signal for adjusting the working state of the third control unit to change the rotation direction of the swing motor to the third control port in the second control mode.

[0026] According to some embodiments of the present disclosure,

[0027] The third control unit comprises a third reversing valve and a pilot valve, the third oil inlet port, the third oil return port, the fifth working port and the sixth working port of the third control unit are respectively connected to the oil inlet port, the oil return port, the first working port and the second working port of the third reversing valve, the pilot valve has an oil inlet port, an oil return port, a working port and an electric control end, the oil inlet port of the pilot valve is connected to the hydraulic oil source, the oil return port of the pilot valve is connected to the oil return pipeline, the working port of the pilot valve is connected to the control end of the third reversing valve, and the third control port is the electric control end of the pilot valve;

[0028] The control room control device includes an electric control handle, which is signal-connected to the third control port to provide the third control port with an electric control signal for adjusting the working state of the third control unit.

[0029] According to some embodiments of the present disclosure,

[0030] The third control unit comprises a third reversing valve, the third oil inlet port, the third oil return port, the fifth working port and the sixth working port of the third control unit are respectively connected to the oil inlet port, the oil return port, the first working port and the second working port of the third reversing valve, and the third control port is the control end of the third reversing valve;

[0031] The control room control device includes a hydraulic handle, and the hydraulic handle is connected to the third control port through a hydraulic pipeline to provide a hydraulic control signal for adjusting the working state of the third control unit to the third control port.

[0032] According to some embodiments of the present disclosure, the hydraulic control system also includes a fourth control unit, the fourth control unit having a fourth oil inlet port, a fourth oil return port, a seventh working port, an eighth working port and a fourth control port, the fourth oil inlet port being connected to the hydraulic oil source, the fourth oil return port being connected to the oil return pipeline, the seventh working port being connected to the first oil inlet port and the second oil inlet port, the eighth working port being connected to the third oil inlet port, and the fourth control unit being configured to switch the control unit that supplies oil to the swing motor according to a control signal of the fourth control port to change the control mode of the hydraulic control system.

[0033] According to some embodiments of the present disclosure, the fourth control unit includes a fourth reversing valve, the fourth oil inlet port, the seventh working port and the eighth working port of the fourth control unit are respectively connected to the oil inlet port, the first working port and the second working port of the fourth reversing valve, and the fourth control port is the control end of the fourth reversing valve.

[0034] In the hydraulic control system of the crane provided in the embodiment of the present disclosure, the first control unit includes a flow regulating part. According to the requirement for the turntable rotation speed when the counterweight block is hung, the flow regulating part can be used to set the flow of the hydraulic oil of the first working port or the second working port, so that the flow of the hydraulic oil of the slewing motor can be kept stable, which is beneficial to improving the problem of no slewing action or too fast slewing action of the turntable caused by the difficulty in ensuring the consistency of the electromagnets and valve stems of different slewing control valves, and is beneficial to making the slewing speed of the turntable more stable. When the flow of the hydraulic oil of the slewing motor is small, the turntable can maintain good operational micro-motion.

[0035] The second aspect of the present disclosure provides a crane, comprising the hydraulic control system according to the first aspect of the present disclosure. The crane provided by the embodiment of the present disclosure has the advantages of the hydraulic control system provided by the embodiment of the present disclosure.

[0036] Other features and advantages of the present disclosure will become apparent from the following detailed description of exemplary embodiments of the present disclosure with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] The drawings described herein are used to provide a further understanding of the present disclosure and constitute a part of the present application. The illustrative embodiments of the present disclosure and their descriptions are used to explain the present disclosure and do not constitute an improper limitation on the present disclosure. In the drawings:

[0038] Figure 1 A schematic diagram of the hydraulic principles of a hydraulic control system of a crane according to some embodiments of the present disclosure.

[0039] Figure 2 Schematic diagram of the hydraulic principle of the hydraulic control system of a crane according to other embodiments of the present disclosure.

[0040] Figure 3 The present invention is a schematic diagram of the hydraulic principle of a hydraulic control system of a crane according to some other embodiments of the present invention. DETAILED DESCRIPTION

[0041] The following will be combined with the drawings in the embodiments of the present disclosure to clearly and completely describe the technical solutions in the embodiments of the present disclosure. Obviously, the described embodiments are only part of the embodiments of the present disclosure, rather than all of the embodiments. The following description of at least one exemplary embodiment is actually only illustrative and is by no means intended to limit the present disclosure and its application or use. Based on the embodiments in the present disclosure, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present disclosure.

[0042] Unless otherwise specifically stated, the relative arrangement of the parts and steps described in these embodiments, numerical expressions and numerical values ​​do not limit the scope of the present disclosure. At the same time, it should be understood that, for ease of description, the sizes of the various parts shown in the accompanying drawings are not drawn according to the actual proportional relationship. The technology, methods and equipment known to ordinary technicians in the relevant field may not be discussed in detail, but in appropriate cases, these technologies, methods and equipment should be regarded as a part of the authorization specification. In all examples shown and discussed here, any specific value should be interpreted as being merely exemplary, rather than as a limitation. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters represent similar items in the following drawings, so once a certain item is defined in an accompanying drawing, it does not need to be further discussed in subsequent drawings.

[0043] In the description of the present disclosure, it should be understood that the use of terms such as "first" and "second" to limit components is only for the convenience of distinguishing the corresponding components. Unless otherwise stated, the above terms have no special meaning and therefore cannot be understood as limiting the scope of protection of the present disclosure.

[0044] In the description of the present disclosure, it is necessary to understand that the orientation or positional relationship indicated by directional words such as "front, back, up, down, left, right", "lateral, vertical, perpendicular, horizontal" and "top, bottom" are usually based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present disclosure and simplifying the description. Unless otherwise specified, these directional words do not indicate or imply that the device or element referred to must have a specific orientation or be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the scope of protection of the present disclosure; the directional words "inside and outside" refer to the inside and outside relative to the outline of each component itself.

[0045] like Figures 1 to 3 As shown, some embodiments of the present disclosure provide a hydraulic control system for a crane, including a hydraulic oil source, a slewing motor 1 , a counterweight cylinder, a first control unit 5 and a second control unit 4 .

[0046] The hydraulic oil source may be a gear pump or the like.

[0047] The slewing motor 1 has a first working port M1 and a second working port M2 and is configured to drive the slewing table of the crane.

[0048] The counterweight oil cylinder has a first working port and a second working port, and is configured to drive the counterweight block of the crane to move up and down relative to the turntable of the crane so as to hang the counterweight block on the turntable.

[0049] The first control unit 5 has a first oil inlet port P1, a first oil return port T1, a first working port A1, a second working port B1 and a first control port. The first oil inlet port P1 is connected to the hydraulic oil source, the first oil return port T1 is connected to the oil return pipeline, the first working port A1 is connected to the first working port M1 of the rotary motor 1, and the second working port B1 is connected to the second working port M2 of the rotary motor 1. The first control unit 5 includes a flow regulating unit for regulating the flow of the hydraulic oil of the first working port A1 or the second working port B1. The first control unit 5 is configured to adjust the flow direction of the hydraulic oil of the first working port A1 and the second working port B1 according to the control signal of the first control port to change the rotation direction of the rotary motor 1.

[0050] exist Figures 1 to 3In the illustrated embodiment, the first control unit 5 has a first working state and a second working state. In the first working state of the first control unit 5, the first working port A1 is inlet and the second working port B1 is outlet. At this time, the flow regulating unit is used to regulate the flow of the hydraulic oil of the second working port B1. In the second working state of the first control unit 5, the first working port A1 is outlet and the second working port B1 is inlet. At this time, the flow regulating unit is used to regulate the flow of the hydraulic oil of the first working port A1. The first control port regulates the working state of the first control unit 5 according to the control signal to change the rotation direction of the slewing motor 1 by changing the flow direction of the hydraulic oil of the first working port A1 and the second working port B1. The first control port of the first control unit 5 can be an electronic control port, and a control signal is sent to the first control port by a remote control device of the crane.

[0051] The second control unit 4 has a second oil inlet port P2, a second oil return port T2, a third working port A2, a fourth working port B2 and a second control port. The second oil inlet port P2 is connected to the hydraulic oil source, the second oil return port T2 is connected to the oil return pipeline, the third working port A2 is connected to the first working port of the counterweight cylinder, and the fourth working port B2 is connected to the second working port of the counterweight cylinder. The second control unit 4 is configured to adjust the flow direction of the hydraulic oil in the third working port A2 and the fourth working port B2 according to the control signal of the second control port to change the moving direction of the piston rod of the counterweight cylinder relative to the cylinder barrel.

[0052] exist Figures 1 to 3 In the illustrated embodiment, the second control unit 4 has a first working state and a second working state. In the first working state of the second control unit 4, oil enters the third working port A2 and oil exits the fourth working port B2. In the second working state of the second control unit 4, oil exits the third working port A2 and oil enters the fourth working port B2. The second control port adjusts the working state of the second control unit 4 according to the control signal to change the moving direction of the piston rod of the counterweight cylinder relative to the cylinder barrel by changing the flow direction of the hydraulic oil in the third working port A2 and the fourth working port B2.

[0053] In the hydraulic control system of the crane provided in the embodiment of the present disclosure, the first control unit includes a flow regulating part. According to the requirement for the turntable rotation speed when the counterweight block is hung, the flow regulating part can be used to set the flow of the hydraulic oil of the first working port or the second working port, so that the flow of the hydraulic oil of the slewing motor can be kept stable, which is beneficial to improving the problem of no slewing action or too fast slewing action of the turntable caused by the difficulty in ensuring the consistency of the electromagnets and valve stems of different slewing control valves, and is beneficial to making the slewing speed of the turntable more stable. When the flow of the hydraulic oil of the slewing motor is small, the turntable can maintain good operational micro-motion.

[0054] In some embodiments, Figures 1 to 3 As shown, the first control unit 5 includes a first reversing valve 51, and the first oil inlet port P1, the first oil return port T1, the first working port A1 and the second working port B1 of the first control unit 5 are respectively connected to the oil inlet port, the oil return port, the first working port and the second working port of the first reversing valve 51, and the first control port is the control end of the first reversing valve 51.

[0055] In some embodiments, Figures 1 to 3 As shown, the second control unit 4 includes a second reversing valve 41, and the second oil inlet port P2, the second oil return port T2, the third working port A2 and the fourth working port B2 of the second control unit 4 are respectively connected to the oil inlet port, the oil return port, the first working port and the second working port of the second reversing valve 41, and the second working port is the control end of the second reversing valve 41.

[0056] In the above embodiment, the first reversing valve 51 and the second reversing valve 41 can be three-position four-way electromagnetic reversing valves, and the first control port and the second control port are electrical control ports. The valve position of the three-position four-way reversing valve is switched by an electrical control signal to change the working state of the first control unit 5 and the second control unit 4.

[0057] In some embodiments, Figures 1 to 3 As shown, the flow regulating unit includes a speed regulating valve 52, the oil inlet of the speed regulating valve 52 is connected to the first oil inlet port P1, and the oil outlet of the speed regulating valve 52 is connected to the oil inlet of the first reversing valve 51. The first control unit 5 adjusts the flow of the hydraulic oil of the first working port A1 or the second working port B1 by adjusting the size of the throttle port of the speed regulating valve 52, and the output flow of the speed regulating valve 52 can be determined according to different working conditions of the hooked counterweight.

[0058] In some embodiments, Figure 1 and Figure 3 As shown, the first control unit 5 also includes a first hydraulically controlled one-way valve 53a and a second hydraulically controlled one-way valve 53b, the oil inlet of the first hydraulically controlled one-way valve 53a is connected to the first working port of the first reversing valve 51, the oil outlet of the first hydraulically controlled one-way valve 53a is connected to the first working port A1, the hydraulically controlled port of the first hydraulically controlled one-way valve 53a is connected to the second working port of the first reversing valve 51, the oil inlet of the second hydraulically controlled one-way valve 53b is connected to the second working port of the first reversing valve 51, the oil outlet of the second hydraulically controlled one-way valve 53b is connected to the second working port B1, and the hydraulically controlled port of the second hydraulically controlled one-way valve 53b is connected to the first working port of the first reversing valve 51.

[0059] In other embodiments, Figure 2As shown, the first control unit 5 further includes a first double check valve 55a disposed between the first working port A1 and the first working port of the first reversing valve 51 and a second double check valve 55b disposed between the second working port B1 and the second working port of the first reversing valve 51, and the first double check valve 55a and the second double check valve 55b each include two parallel check valves with opposite conduction directions. By providing the first hydraulically controlled check valve 53a and the second hydraulically controlled check valve 53b, or providing the first double check valve 55a and the second double check valve 55b, the rotary motor can be prevented from rotating in the reverse direction due to a negative load that generates a torque opposite to its rotation direction during micro-motion, thereby making the turntable more stable when rotating at a low speed.

[0060] Figure 2 In the embodiment shown, in order to better prevent the rotary motor from rotating in the reverse direction due to negative load, the one-way valve in the first double one-way valve 55a that is connected from the first reversing valve 51 to the rotary motor 1 is Figure 2 The opening pressure of the left check valve in the first double check valve 55a is P1, and the check valve in the first double check valve 55a that is connected from the rotary motor 1 to the first reversing valve 51, that is, Figure 2 The opening pressure of the one-way valve on the right side of the first double one-way valve 55a is P2, then P1 and P2 need to satisfy the relationship of P1<P2; similarly, the one-way valve in the first double one-way valve 55b that is connected from the first reversing valve 51 to the rotary motor 1, that is, Figure 2 The opening pressure of the one-way valve on the right side of the first double one-way valve 55b is P3. The one-way valve in the first double one-way valve 55b that is connected from the rotary motor 1 to the first reversing valve 51 is Figure 2 The opening pressure of the left one-way valve in the first double one-way valve 55b is P4, and P3 and P4 need to satisfy the magnitude relationship P3<P4.

[0061] In some embodiments, the first control unit 5 further includes a first one-way valve 54, the oil inlet of the first one-way valve 54 is connected to the oil return port of the first reversing valve 51, and the oil outlet of the first one-way valve 54 is connected to the first oil return port T1. The first one-way valve 54 can establish a certain back pressure between the oil return port of the first reversing valve 51 and the first oil return port T1, so that the action of the rotary motor is more stable.

[0062] In some embodiments, the second control unit 4 further includes a second one-way valve 42, the oil inlet of the second one-way valve 42 is connected to the oil return port of the second reversing valve 41, and the oil outlet of the second one-way valve 42 is connected to the second oil return port T2. The second one-way valve 42 is set to establish a certain back pressure between the oil return port of the second reversing valve 41 and the second oil return port T2, so that the movement of the counterweight cylinder is more stable.

[0063] In some embodiments, the hydraulic control system further includes a third control unit 2. The third control unit 2 has a third oil inlet port P, a third oil return port T, a fifth working port A, a sixth working port B and a third control port. The third oil inlet port P is connected to the hydraulic oil source, the third oil return port T is connected to the oil return line, the fifth working port A is connected to the first working port M1 of the swing motor 1, and the sixth working port B is connected to the second working port M2 of the swing motor 1. The third control unit 2 is configured to adjust the flow direction of the hydraulic oil of the fifth working port A and the sixth working port B according to the control signal of the third control port to change the rotation direction of the swing motor 1. The hydraulic control system has a first control mode and a second control mode. In the first control mode, the hydraulic oil source is connected to the first oil inlet port P1 and disconnected from the third oil inlet port P, and the hydraulic oil source supplies oil to the swing motor 1 through the first control unit 5. In the second control mode, the hydraulic oil source is connected to the third oil inlet port P and disconnected from the first oil inlet port P1, and the hydraulic oil source supplies oil to the swing motor 1 through the third control unit 2.

[0064] exist Figures 1 to 3 In the illustrated embodiment, the third control unit 2 has a first working state and a second working state. In the first working state of the third control unit 2, oil is taken in by the fifth working port A and oil is discharged from the sixth working port B. In the second working state of the third control unit 2, oil is discharged from the fifth working port A and oil is taken in by the sixth working port B. The third control port is configured to adjust the working state of the first control unit 5 according to the control signal so as to change the rotation direction of the rotary motor 1 by changing the flow direction of the hydraulic oil of the fifth working port A and the sixth working port B.

[0065] The first control mode mentioned above may correspond to the situation of controlling the rotation of the turntable in the crane control room, and the second control mode may correspond to the situation of using a remote control device to control the rotation motor and the counterweight cylinder when the counterweight is attached.

[0066] In some embodiments, on the basis of setting the third control unit 2, the hydraulic control system further includes a remote control device and a control room control device. The remote control device is signal-connected to the first control port and the second control port. The remote control device is configured to provide a control signal for adjusting the working state of the first control unit 5 to change the rotation direction of the swing motor 1 to the first control port in the first control mode, and to provide a control signal for adjusting the working state of the second control unit 4 to change the moving direction of the piston rod of the counterweight cylinder relative to the cylinder barrel to the second control port. The control room control device is configured to provide a control signal for adjusting the working state of the third control unit 2 to change the rotation direction of the swing motor 1 to the third control port in the second control mode.

[0067] In some embodiments, Figure 1 and Figure 2As shown, the third control unit 2 includes a third reversing valve 21 and a pilot valve. The third oil inlet port P, the third oil return port T, the fifth working port A and the sixth working port B of the third control unit are respectively connected to the oil inlet, the oil return port, the first working port and the second working port of the third reversing valve 21. The pilot valve has an oil inlet, an oil return port, a working port and an electric control end. The oil inlet of the pilot valve is connected to the hydraulic oil source, the oil return port of the pilot valve is connected to the oil return pipeline, the working port of the pilot valve is connected to the control end of the third reversing valve 21, and the third control port is the electric control end of the pilot valve. The control room control device includes an electric control handle, which is connected to the third control port signal to provide the third control port with an electric control signal for adjusting the working state of the third control unit 2.

[0068] like Figure 1 and Figure 2 In the illustrated embodiment, the third control unit also includes a rotary buffer valve 22 arranged between the two working ports of the third reversing valve 21 and the two working ports of the rotary motor 1, the pilot valve includes a first pilot valve 23a and a second pilot valve 23b, the third reversing valve 21 is a three-position four-way hydraulically controlled reversing valve, and the two hydraulically controlled ends of the third reversing valve 21 are respectively connected to the working port of the first pilot valve 23a and the working port of the second pilot valve 23b.

[0069] In the related art known to the inventor, when the turntable is operated to rotate in the control room of the crane, the first pilot valve 23a and the second pilot valve 23b are controlled by the electric control handle set in the control room, and when the turntable is operated to rotate in the process of hanging the counterweight, the first pilot valve 23a and the second pilot valve 23b are controlled by the button switch on the remote control device. Although the control signal output by the button switch on the remote control device is a constant current, it is difficult to ensure the consistency of components such as valve stems and electromagnets between the first pilot valve 23a and the second pilot valve 23b of the same crane, between the first pilot valves 23a of different cranes, and between the second pilot valves 23b of different cranes. The flow rate of hydraulic oil output by different pilot valves under the same control signal is often different, and the hydraulic control signal acting on the third reversing valve 21 is also different, resulting in different cranes using remote control to hang the counterweight. When the rotation speed of the slewing motor is consistent, it is also difficult to ensure that the slewing motor of some cranes does not move or rotates too fast.

[0070] In the embodiment of the present disclosure, the remote control device controls the first control port of the first control unit 5. Under the control signal of the remote control device, the two oil inlets of the first reversing valve 51 are connected to one of the two working ports of the first reversing valve 51, and thus connected to one of the two working ports of the slewing motor 1. Under the action of the speed regulating valve 52, for different cranes, the flow rate of the hydraulic oil flowing through the slewing motor 1 can always remain stable, so that the rotation speed of the slewing motor 1 and the turntable remains stable, which is beneficial to improve the problem of no slewing action or too fast slewing action of the turntable when the counterweight is attached by remote control.

[0071] In other embodiments, Figure 3 As shown, the third control unit 2 includes a third reversing valve 21, and the third oil inlet port P, the third oil return port T, the fifth working port A and the sixth working port B of the third control unit are respectively connected to the oil inlet port, the oil return port, the first working port and the second working port of the third reversing valve 21, and the third control port is the control end of the third reversing valve 51. The control room control device includes a hydraulic handle, which is connected to the third control port through a hydraulic pipeline to provide a hydraulic control signal for adjusting the working state of the third control unit 2 to the third control port.

[0072] In some embodiments, on the basis of setting up the third control unit 2, the hydraulic control system also includes a fourth control unit 3, the fourth control unit 3 has a fourth oil inlet port P0, a fourth oil return port T0, a seventh working port C1, an eighth working port C2 and a fourth control port, the fourth oil inlet port P0 is connected to the hydraulic oil source, the fourth oil return port T0 is connected to the return oil pipeline, the seventh working port C1 is connected to the first oil inlet port P1 and the second oil inlet port P2, the eighth working port C2 is connected to the third oil inlet port P, and the fourth control unit 3 is configured to switch the control unit that supplies oil to the rotary motor 1 according to the control signal of the fourth control port to change the control mode of the hydraulic control system.

[0073] exist Figures 1 to 3 In the illustrated embodiment, the fourth control unit 3 has a first working state and a second working state. In the first working state of the fourth control unit 3, the fourth oil inlet port P0 is connected to the seventh working port C1 and disconnected from the eighth working port C2. In the second working state of the fourth control unit 3, the fourth oil inlet port P0 is connected to the eighth working port C2 and disconnected from the seventh working port C1. The fourth control port is configured to adjust the working state of the fourth control unit according to the control signal to change the control mode of the hydraulic control system by switching the control unit that supplies oil to the swing motor 1.

[0074] In some embodiments, the fourth control unit 3 includes a fourth reversing valve 31, and the fourth oil inlet port P0, the seventh working port C1 and the eighth working port C2 of the fourth control unit 3 are respectively connected to the oil inlet, the first working port and the second working port of the fourth reversing valve 31, and the fourth control port is the control end of the fourth reversing valve 31.

[0075] In some embodiments not shown in the figures, the hydraulic control system of the crane may also not include the fourth control unit 3, and the first oil inlet port P1, the second oil inlet port P2 and the third oil inlet port P3 are directly connected to the hydraulic oil source instead of being connected to the hydraulic oil source through the fourth control unit 3.

[0076] The first control unit 5, the second control unit 4, the third control unit 3 and the fourth control unit 2 can all be modularly connected to the hydraulic control system of the crane, which can avoid occupying additional space of the crane, help reduce the manufacturing cost of the crane and maintain the aesthetic appearance of the crane.

[0077] Combine the following Figures 1 to 3 The working process of the hydraulic control system of the crane according to the embodiment of the present disclosure is further explained.

[0078] When the rotation of the turntable is controlled by the electric control handle or the hydraulic control handle in the crane control room, the fourth reversing valve 31 is in the left position, and the high-pressure hydraulic oil output by the hydraulic oil source flows into the slewing motor 1 through the fourth reversing valve 31, the third reversing valve 21 and the slewing buffer valve 22, driving the slewing motor 1 to rotate, thereby driving the turntable to rotate.

[0079] When the rotation of the turntable is controlled by the remote control device, the fourth reversing valve 31 is in the right position, the second reversing valve 41 is in the middle position, and the high-pressure hydraulic oil output by the hydraulic oil source flows into the speed regulating valve 52 through the fourth reversing valve 31. The speed regulating valve 52 outputs hydraulic oil with a constant flow rate, and then flows into the first working port M1 or the second working port M2 of the rotary motor 1 through the first reversing valve 51, through the first working port A1 or the second working port B1, to drive the rotary motor 1 to rotate, thereby driving the turntable to rotate.

[0080] When the telescopic movement of the piston rod of the counterweight cylinder is controlled by the remote control device, the fourth reversing valve 31 is in the right position, and the high-pressure hydraulic oil output by the hydraulic oil source passes through the fourth reversing valve 31 and the second reversing valve 41, and then flows into the rodless chamber or the rod chamber of the counterweight cylinder through the third working port A2 or the fourth working port B2, thereby controlling the telescopic movement of the piston rod of the counterweight cylinder.

[0081] When the first reversing valve 51 is in the left position or the right position, the first hydraulically controlled one-way valve 53a and the second hydraulically controlled one-way valve 53b are in an open state under the action of the hydraulic oil pressure, and the hydraulic oil can pass through normally in both directions; when the first reversing valve 51 is in the middle position, the first hydraulically controlled one-way valve 53a and the second hydraulically controlled one-way valve 53b are in a closed state, and the hydraulic oil cannot flow from the first working port A1 and the second working port B1 to the first reversing valve 51, thereby preventing the rotary motor 1 from being subjected to negative load and rotating in the opposite direction during micro-motion.

[0082] Some embodiments of the present disclosure also provide a crane, comprising the above-mentioned hydraulic control system. The crane provided by the embodiments of the present disclosure has the advantages of the hydraulic control system provided by the embodiments of the present disclosure.

[0083] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present disclosure rather than to limit it. Although the present disclosure has been described in detail with reference to the preferred embodiments, ordinary technicians in the relevant field should understand that the specific implementation methods of the present disclosure can still be modified or some technical features can be replaced by equivalents, which should all be included in the scope of the technical solution for protection requested by the present disclosure.

Claims

1. A hydraulic control system for a crane, characterized in that: include: Hydraulic oil source; A slewing motor (1) having a first working port (M1) and a second working port (M2), configured to drive the slewing table of the crane; a counterweight cylinder having a first working port and a second working port, and configured to drive the counterweight of the crane to move up and down relative to the turntable of the crane so as to hang the counterweight on the turntable; a first control unit (5), comprising a first oil inlet port (P1), a first oil return port (T1), a first working port (A1), a second working port (B1) and a first control port, wherein the first oil inlet port (P1) is connected to the hydraulic oil source, the first oil return port (T1) is connected to the oil return pipeline, the first working port (A1) is connected to the first working port (M1) of the rotary motor (1), and the second working port (B1) is connected to the second working port (M2) of the rotary motor (1), the first control unit (5) comprises a flow regulating unit for regulating the flow of the hydraulic oil of the first working port (A1) or the second working port (B1), and the first control unit (5) is configured to regulate the flow direction of the hydraulic oil of the first working port (A1) and the second working port (B1) according to a control signal of the first control port, so as to change the rotation direction of the rotary motor (1); and The second control unit (4) has a second oil inlet port (P2), a second oil return port (T2), a third working port (A2), a fourth working port (B2) and a second control port, wherein the second oil inlet port (P2) is connected to the hydraulic oil source, the second oil return port (T2) is connected to the oil return pipeline, the third working port (A2) is connected to the first working port of the counterweight cylinder, and the fourth working port (B2) is connected to the second working port of the counterweight cylinder. The second control unit (4) is configured to adjust the flow direction of the hydraulic oil of the third working port (A2) and the fourth working port (B2) according to the control signal of the second control port to change the moving direction of the piston rod of the counterweight cylinder relative to the cylinder barrel.

2. The hydraulic control system of a crane according to claim 1, characterized in that: The first control unit (5) comprises a first reversing valve (51), the first oil inlet port (P1), the first oil return port (T1), the first working port (A1) and the second working port (B1) of the first control unit (5) are respectively connected to the oil inlet port, the oil return port, the first working port and the second working port of the first reversing valve (51), and the first control port is the control end of the first reversing valve (51); and / or The second control unit (4) comprises a second reversing valve (41); the second oil inlet port (P2), the second oil return port (T2), the third working port (A2) and the fourth working port (B2) of the second control unit (4) are respectively connected to the oil inlet port, the oil return port, the first working port and the second working port of the second reversing valve (41); the second working port is the control end of the second reversing valve (41).

3. The hydraulic control system of a crane according to claim 2, characterized in that: The flow regulating unit comprises a speed regulating valve (52), the oil inlet of the speed regulating valve (52) is connected to the first oil inlet port (P1), and the oil outlet of the speed regulating valve (52) is connected to the oil inlet of the first reversing valve (51).

4. The hydraulic control system of a crane according to claim 2, characterized in that: The first control unit (5) further comprises a first hydraulically controlled one-way valve (53a) and a second hydraulically controlled one-way valve (53b), wherein the oil inlet of the first hydraulically controlled one-way valve (53a) is connected to the first working port of the first reversing valve (51), the oil outlet of the first hydraulically controlled one-way valve (53a) is connected to the first working port (A1), the hydraulically controlled port of the first hydraulically controlled one-way valve (53a) is connected to the second working port of the first reversing valve (51), the oil inlet of the second hydraulically controlled one-way valve (53b) is connected to the second working port of the first reversing valve (51), the oil outlet of the second hydraulically controlled one-way valve (53b) is connected to the second working port (B1), and the hydraulically controlled port of the second hydraulically controlled one-way valve (53b) is connected to the first working port of the first reversing valve (51).

5. The hydraulic control system of a crane according to claim 2, characterized in that: The first control unit (5) further comprises a first double check valve (55a) arranged between the first working port (A1) and the first working port of the first reversing valve (51), and a second double check valve (55b) arranged between the second working port (B1) and the second working port of the first reversing valve (51), wherein the first double check valve (55a) and the second double check valve (55b) each comprise two parallel check valves with opposite conduction directions.

6. The hydraulic control system of a crane according to claim 2, characterized in that: The first control unit (5) further comprises a first one-way valve (54), an oil inlet of the first one-way valve (54) being connected to an oil return port of the first reversing valve (51), and an oil outlet of the first one-way valve (54) being connected to the first oil return port (T1); and / or The second control unit (4) further comprises a second one-way valve (42), the oil inlet of the second one-way valve (42) being connected to the oil return port of the second reversing valve (41), and the oil outlet of the second one-way valve (42) being connected to the second oil return port (T2).

7. The hydraulic control system of a crane according to any one of claims 1 to 6, characterized in that: The hydraulic control system further comprises a third control unit (2), the third control unit (2) having a third oil inlet port (P), a third oil return port (T), a fifth working port (A), a sixth working port (B) and a third control port, the third oil inlet port (P) being connected to the hydraulic oil source, the third oil return port (T) being connected to the oil return pipeline, the fifth working port (A) being connected to the first working port (M1) of the swing motor (1), the sixth working port (B) being connected to the second working port (M2) of the swing motor (1), the third control unit (2) being configured to adjust the flow direction of the hydraulic oil of the fifth working port (A) and the sixth working port (B) according to the control signal of the third control port, so as to change the rotation direction of the swing motor (1); The hydraulic control system has a first control mode and a second control mode. In the first control mode, the hydraulic oil source is connected to the first oil inlet port (P1) and disconnected from the third oil inlet port (P), and the hydraulic oil source supplies oil to the swing motor (1) through the first control unit (5). In the second control mode, the hydraulic oil source is connected to the third oil inlet port (P) and disconnected from the first oil inlet port (P1), and the hydraulic oil source supplies oil to the swing motor (1) through the third control unit (2).

8. The hydraulic control system of a crane according to claim 7, characterized in that: The hydraulic control system further comprises: a remote control device connected to the first control port and the second control port by signals, the remote control device being configured to provide, in the first control mode, to the first control port a control signal for adjusting the working state of the first control unit (5) to change the rotation direction of the rotary motor (1), and to provide to the second control port a control signal for adjusting the working state of the second control unit (4) to change the moving direction of the piston rod of the counterweight cylinder relative to the cylinder barrel; and The control room control device is configured to provide the third control port with a control signal for adjusting the working state of the third control unit (2) to change the rotation direction of the rotary motor (1) in the second control mode.

9. The hydraulic control system of a crane according to claim 8, characterized in that: The third control unit (2) comprises a third reversing valve (21) and a pilot valve; the third oil inlet port (P), the third oil return port (T), the fifth working port (A) and the sixth working port (B) of the third control unit are respectively connected to the oil inlet port, the oil return port, the first working port and the second working port of the third reversing valve (21); the pilot valve has an oil inlet port, an oil return port, a working port and an electric control end; the oil inlet port of the pilot valve is connected to the hydraulic oil source; the oil return port of the pilot valve is connected to the oil return pipeline; the working port of the pilot valve is connected to the control end of the third reversing valve (21); and the third control port is the electric control end of the pilot valve; The control room control device comprises an electric control handle, which is signal-connected to the third control port to provide the third control port with an electric control signal for adjusting the working state of the third control unit (2).

10. The hydraulic control system of a crane according to claim 8, characterized in that: The third control unit (2) comprises a third reversing valve (21), the third oil inlet port (P), the third oil return port (T), the fifth working port (A) and the sixth working port (B) of the third control unit are respectively connected to the oil inlet port, the oil return port, the first working port and the second working port of the third reversing valve (21), and the third control port is the control end of the third reversing valve (21); The control room control device comprises a hydraulic handle, which is connected to the third control port through a hydraulic pipeline to provide a hydraulic control signal for adjusting the working state of the third control unit (2) to the third control port.

11. The hydraulic control system of a crane according to claim 7, characterized in that: The hydraulic control system further comprises a fourth control unit (3), the fourth control unit (3) having a fourth oil inlet port (P0), a fourth oil return port (T0), a seventh working port (C1), an eighth working port (C2) and a fourth control port, the fourth oil inlet port (P0) being connected to the hydraulic oil source, the fourth oil return port (T0) being connected to the oil return line, the seventh working port (C1) being connected to the first oil inlet port (P1) and the second oil inlet port (P2), the eighth working port (C2) being connected to the third oil inlet port (P), the fourth control unit (3) being configured to switch the control unit for supplying oil to the rotary motor (1) according to the control signal of the fourth control port, so as to change the control mode of the hydraulic control system.

12. The hydraulic control system of a crane according to claim 11, characterized in that: The fourth control unit (3) comprises a fourth reversing valve (31); the fourth oil inlet port (P0), the seventh working port (C1) and the eighth working port (C2) of the fourth control unit (3) are respectively connected to the oil inlet port, the first working port and the second working port of the fourth reversing valve (31); the fourth control port is the control end of the fourth reversing valve (31).

13. A crane, characterized in that: Comprising a hydraulic control system according to any one of claims 1 to 12.

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