A hoist braking control system, method and crane

Abstract

This invention relates to the field of hoist control technology, disclosing a hoist braking control system and method. The system includes: a hoist brake connected to a hydraulically controlled directional valve via a pipeline; the hydraulically controlled directional valve connected to an oil pump via a supply branch pipeline, and the hydraulically controlled directional valve connected to an oil tank via a return branch pipeline; the oil pump is also connected to the oil tank via a pipeline; the hydraulically controlled directional valve controls the on / off state of the supply and return oil paths; the hydraulically controlled pilot end of the hydraulically controlled directional valve is connected to a lifting control device; a torque compensation unit is connected to the spring end of the hydraulically controlled directional valve, the torque compensation unit is communicatively connected to a controller, and the controller is communicatively connected to a tension sensor, which is used to detect the tension of the load acting on the wire rope. This invention delays brake unlocking under heavy loads, solving the problem of hook slippage under heavy loads.

Description

Technical Field

[0001] This invention relates to the field of hoist control technology, specifically to a hoist braking control system, method, and crane. Background Technology

[0002] Winches are essential equipment in cranes. They are small, lightweight lifting devices that use a drum to wind wire rope or chain to lift or pull heavy objects. Winches can lift vertically and pull horizontally or at an angle. They are widely used due to their simple operation, large rope capacity, and ease of relocation. After a heavy object is attached to the crane hook, the winch brake needs to be locked when no lifting or lowering operation is being performed. When lifting or lowering a heavy object, the winch brake needs to be released. However, if the weight of the object being lifted is very large, the lifting force of the lifting system may not accurately compensate for the weight of the object, which can easily lead to hook slippage under heavy load when the winch brake is released. Therefore, how to prevent hook slippage under heavy load when the winch brake is released is a problem that needs to be solved. Summary of the Invention

[0003] In view of this, the present invention provides a winch braking control system, method and crane to solve the problem of hook slippage under heavy load when the winch brake is unlocked.

[0004] In a first aspect, the present invention provides a winch braking control system, comprising: a hydraulic motor, a winch brake, a hydraulically controlled directional valve, an oil tank, an oil pump, a lifting control device, a controller, a tension sensor, and a torque compensation unit; the hydraulic motor is used to drive the winch; the piston rod of the winch brake can abut against the output shaft of the hydraulic motor to control the rotation of the hydraulic motor; the winch brake is connected to the hydraulically controlled directional valve via a pipeline; the hydraulically controlled directional valve is connected to the oil pump via a supply branch pipeline, and the hydraulically controlled directional valve is connected to the oil tank via a return branch pipeline; the oil pump is also connected to the oil tank via a pipeline; the hydraulically controlled directional valve is used to control the on / off state of the supply and return oil paths; the hydraulically controlled pilot end of the hydraulically controlled directional valve is connected to the lifting control device; the torque compensation unit is connected to the spring end of the hydraulically controlled directional valve, the torque compensation unit is communicatively connected to the controller, the controller is communicatively connected to the tension sensor, and the tension sensor is used to detect the tension of the load acting on the wire rope.

[0005] In some alternative embodiments, the torque compensation unit includes a motor and a rack, the motor being communicatively connected to the controller, the rack being connected to the motor shaft via gears, one end of the rack facing the spring end of the hydraulic directional valve, the motor being used to control the rack to move toward the spring end of the hydraulic directional valve by rotation, and one end of the rack being used to provide compensation force by abutting against the spring end of the hydraulic directional valve.

[0006] In some optional embodiments, the torque compensation unit is disposed in the return oil branch; wherein the torque compensation unit includes a first solenoid directional valve and a relief valve, the control terminal of the first solenoid directional valve is communicatively connected to the controller, the input terminal of the first solenoid directional valve is connected to the return oil end pipeline of the hydraulic directional valve, the first output terminal of the first solenoid directional valve is connected to the oil tank pipeline, the second output terminal of the first solenoid directional valve is connected to the input terminal pipeline of the relief valve, the output terminal of the relief valve is connected to the oil tank pipeline, and the return oil end of the hydraulic directional valve is also connected to the spring end pipeline of the hydraulic directional valve; the first solenoid directional valve includes a third working position and a fourth working position, the third working position is used to connect the input terminal and the first output terminal of the first solenoid directional valve, and the fourth working position is used to connect the input terminal and the second output terminal of the first solenoid directional valve.

[0007] In some alternative embodiments, a solenoid valve is also included, which is disposed between the lifting control device and the hydraulic pilot end of the hydraulic directional valve, the solenoid valve being communicatively connected to the controller, and the controller being communicatively connected to the tension sensor.

[0008] In some optional embodiments, the solenoid valve is a second solenoid directional valve. The output end of the second solenoid directional valve is connected to the hydraulic pilot end pipeline of the hydraulic directional valve. The first input end of the second solenoid directional valve is connected to the return oil branch. The second input end of the second solenoid directional valve is connected to the output end pipeline of the lifting control device. The spring end of the hydraulic directional valve is connected to the return oil branch. The control end of the second solenoid directional valve is communicatively connected to the controller. The second solenoid directional valve includes a fifth working position and a sixth working position. The fifth working position is used to connect the first input end and the output end of the second solenoid directional valve, and the sixth working position is used to connect the second input end and the output end of the second solenoid directional valve.

[0009] Secondly, the present invention provides a hoist braking control method for a controller, comprising: when the hydraulic control handle is operated, detecting a tension value by a tension sensor; when the tension value is greater than a preset force threshold, performing torque compensation on the spring end of the hydraulic control directional valve by a torque compensation unit.

[0010] In some alternative embodiments, the torque compensation of the spring end of the hydraulic directional valve by the torque compensation unit includes: controlling the first electromagnetic directional valve to switch from the third working position to the fourth working position.

[0011] In some optional embodiments, the method further includes: when the tension value is less than or equal to the preset force threshold, opening the solenoid valve after a first preset time to connect the output end of the lifting control device with the hydraulic pilot end of the hydraulic directional valve; when the tension value is greater than the preset force threshold, opening the solenoid valve after a second preset time to connect the output end of the lifting control device with the hydraulic pilot end of the hydraulic directional valve, wherein the second preset time is greater than the first preset time.

[0012] In some optional embodiments, the step of opening the solenoid valve after a first preset time when the tension value is less than or equal to the preset force threshold includes: switching the second solenoid directional valve from the fifth working position to the sixth working position after a first preset time when the tension value is less than or equal to the preset force threshold.

[0013] In some optional embodiments, the step of opening the solenoid valve after a second preset time when the tension value is greater than the preset force threshold includes: switching the second solenoid directional valve from the fifth working position to the sixth working position after a second preset time when the tension value is greater than the preset force threshold.

[0014] Thirdly, the present invention provides a crane, comprising a vehicle body, a hook, a winch, and a winch braking control system provided in any one of the first aspects; the winch is mounted on the vehicle body, the wire rope of the winch is connected to the hook, the hook is suspended from the far end of the boom of the vehicle body via the wire rope, the winch braking control system is disposed within the vehicle body, and the hydraulic motor in the winch braking control system is connected to the drive shaft of the winch.

[0015] The technical solution provided by this invention has the following advantages:

[0016] The winch braking control system provided by this invention can detect the weight of the load to be lifted by the crane through a tension sensor, thereby determining whether it is a large load. If it is a large load, the controller can control the torque compensation unit to apply a compensating force to the spring end of the hydraulic directional valve. This causes the hydraulic directional valve to take longer to open when the hydraulic control handle is actuated, preparing the lifting system to adjust the lifting force according to the load. When the hydraulic directional valve opens, the winch brake is released, and the lifting system has been adjusted. The lifting system can stably lift the load, thus avoiding the problem of hook slippage under heavy load caused by directly releasing the winch brake. Attached Figure Description

[0017] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0018] Figure 1 This is a side view schematic diagram of a crane based on related technologies;

[0019] Figure 2 This is a schematic diagram of the structure of the hoist braking control system of the relevant technology;

[0020] Figure 3 This is a schematic diagram of the structure of the hoist braking control system according to an embodiment of the present invention;

[0021] Figure 4 This is another structural schematic diagram of the hoist braking control system according to an embodiment of the present invention;

[0022] Figure 5 This is another structural schematic diagram of the hoist braking control system according to an embodiment of the present invention;

[0023] Figure 6 This is another structural schematic diagram of the hoist braking control system according to an embodiment of the present invention;

[0024] Figure 7 This is a schematic flowchart of a hoist braking control method according to an embodiment of the present invention.

[0025] Figure label:

[0026] Hydraulic motor 0, winch brake 1, hydraulic directional valve 2, torque compensation unit 3, tension sensor 4, oil pump 5, oil tank 6, shuttle valve 7, hydraulic handle 8, controller 9, solenoid valve 10, second solenoid directional valve 11, lifting control device 12. Detailed Implementation

[0027] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0028] like Figure 1As shown, this is a side view of a crane. The crane has a pivotally connected truss boom and a vehicle body equipped with a cab. A winch (not shown) is a device used in the crane to lift heavy objects. The wire rope in the winch passes through the top of the truss boom and is connected to the hook. The hook is raised and lowered by winding or releasing the wire rope by the winch, thereby lifting and lowering the heavy object attached to the hook.

[0029] like Figure 2 This is a commonly used winch braking control system in related technologies. The system includes: a hydraulic motor 0, a winch brake 1, a hydraulically controlled directional valve 2, an oil tank 6, an oil pump 5, a hydraulically controlled handle 8, and a shuttle valve 7. The connection between the components is that the oil cylinder of the winch brake 1 is connected to the oil outlet pipe of the hydraulically controlled directional valve 2, and the piston rod of the winch brake 1 can abut against the output shaft of the hydraulic motor 0. The extension and retraction of the piston rod is controlled by controlling the pressure difference on both sides of the piston in the oil cylinder. A friction plate is installed at the end of the piston rod. The rotation of the hydraulic motor 0 is controlled by adjusting the distance between the friction plate and the output shaft of the hydraulic motor 0. The inlet of the hydraulic directional valve 2 is connected to the output of the oil pump 5 via a pipeline. The return of the hydraulic directional valve 2 is connected to the oil tank 6 via a return branch pipeline. The input of the oil pump 5 is connected to the oil tank 6 via a pipeline. The hydraulic directional valve 2 includes a first working position and a second working position. The first working position is used to connect the outlet and inlet of the hydraulic directional valve 2, and the second working position is used to connect the outlet and return of the hydraulic directional valve 2. The output of the shuttle valve 7 is connected to the pilot end of the hydraulic directional valve 2 via a pipeline, and the input of the shuttle valve 7 is connected to the control end of the hydraulic handle 8 via a pipeline. The inlet of the hydraulic handle 8 is connected to the output of the oil pump 5 via a pipeline, and the return of the hydraulic handle 8 is connected to the oil tank 6 via a pipeline. In some scenarios, a separate oil pump can also be used to supply hydraulic oil to the hydraulic handle 8.

[0030] In some specific scenarios, the hydraulic control handle 8 is installed in the cab. The hydraulic control handle has an upward side 8a and a downward side 8b. Moving the hydraulic control handle in the upward direction winds the wire rope in the winch, while moving it in the downward direction releases the wire rope. However, regardless of whether it is moving upward or downward, the hydraulic control handle 8 should trigger the hydraulic directional valve 2 to release the winch brake 1. Each of the upward and downward sides 8a and 8b includes an oil inlet connected to the output of the oil pump 5, and each includes a return oil end connected to the oil tank 6. The control ends of both handles are connected to the input of the shuttle valve 7.

[0031] Through the aforementioned winch braking control system, during operation, the operating handle is moved to the lifting side 8a or the lowering side 8b, causing hydraulic oil from the oil pump 5 to flow in from the inlet end of the lifting side 8a or the lowering side 8b, and then to the shuttle valve 7 from the corresponding control end. The shuttle valve 7 transmits the hydraulic oil to the hydraulic pilot end of the hydraulic directional valve 2, which pushes against the spring end of the hydraulic directional valve 2, thus switching the hydraulic directional valve 2 from the second working position to the first working position. The first working position connects the outlet and inlet ends of the hydraulic directional valve 2, allowing the oil output from the oil pump 5 to be transmitted to the cylinder of the winch brake 1. The oil inside the cylinder of the winch brake 1 applies pressure to the spring of the winch brake 1, causing the piston rod of the winch brake 1 to contract and release the lock on the winch.

[0032] However, in practical applications, the lifting system needs a certain amount of time to provide the appropriate lifting force based on the weight of the load. In other words, the hydraulic motor 0 needs a certain preparation time to keep the lifted load stable, meaning that the corresponding lifting port of the hydraulic motor 0 needs to build up pressure. If the weight of the lifted load is very large, the winch brake control system may directly release the lock before the lifting force output by the hydraulic motor 0 of the lifting system accurately compensates for the weight of the load. This can easily lead to the problem of hook slippage under heavy load at the moment the winch lock is released. Therefore, how to prevent hook slippage under heavy load when the winch brake 1 is released is a problem that needs to be solved.

[0033] To address the aforementioned problems, according to an embodiment of the present invention, a hoist braking control system is provided, such as... Figure 3 As shown, it includes: a hydraulic motor 0, a winch brake 1, a hydraulic directional valve 2, an oil tank 6, an oil pump 5, a lifting control device 12, a controller 9, a tension sensor 4, and a torque compensation unit 3.

[0034] The specific connection method is as follows: the cylinder of the winch brake 1 is connected to the outlet pipe of the hydraulic directional valve 2; the inlet pipe of the hydraulic directional valve 2 is connected to the output pipe of the oil pump 5; the input pipe of the oil pump 5 is connected to the oil tank 6 through a pipe; the cylinder of the winch brake 1, the outlet pipe of the hydraulic directional valve 2, the inlet pipe of the hydraulic directional valve 2, and the oil pump 5 form an oil delivery branch; the return pipe of the hydraulic directional valve 2 is connected to the oil tank 6 through a pipe, forming a return branch. The hydraulic directional valve 2 includes a first working position and a second working position, which are used to control the opening and closing of the oil delivery and return paths through the first and second working positions. Specifically, the first working position is used to connect the outlet and inlet pipes of the hydraulic directional valve 2, thereby connecting the oil delivery branch and the winch brake 1; the second working position is used to connect the outlet and return pipes of the hydraulic directional valve 2, thereby connecting the return branch and the winch brake 1. The hydraulic pilot end of the hydraulic directional valve 2 is connected to the lifting control device 12, which is an operating platform for controlling the lifting or releasing of the crane. When the lifting control device 12 is activated, it transmits a corresponding control pilot force to the hydraulic directional valve 2, thereby switching the hydraulic directional valve 2 between the first working position and the second working position.

[0035] exist Figure 3 In this paper, the lifting control device 12 is still described using the structure of shuttle valve 7 and hydraulic control handle 8 as an example to facilitate understanding of the scheme. However, in some other embodiments, the lifting control device 12 can also be replaced with an electronic control structure according to actual needs, as long as the lifting control device 12 can transmit pilot force to the hydraulic pilot end of the hydraulic control directional valve 2 when it is working. Therefore, the present invention does not specifically limit the structure of the lifting control device 12.

[0036] exist Figure 3 In this configuration, the output end of shuttle valve 7 is connected to the pilot end of hydraulic directional valve 2, and the input end of shuttle valve 7 is connected to the control end of hydraulic handle 8. The inlet end of hydraulic handle 8 is connected to the output end of oil pump 5, and the return end of hydraulic handle 8 is connected to oil tank 6. In some scenarios, other oil pumps can also be used separately to supply hydraulic oil to hydraulic handle 8.

[0037] In addition, the torque compensation unit 3 provided in this embodiment of the invention is set at the spring end of the hydraulic control directional valve 2. The torque compensation unit 3 is communicatively connected to the controller 9. The controller 9 is communicatively connected to the tension sensor 4. The tension sensor 4 is connected to the wire rope. The tension sensor 4 is used to detect the tension of the weight acting on the wire rope and to feed back the detected tension to the controller 9.

[0038] Specifically, based on the above connection relationship, the structure and operating principle of the hydraulic motor 0, winch brake 1, hydraulic control directional valve 2, oil tank 6, oil pump 5, hydraulic control handle 8, and shuttle valve 7 in the embodiments of the present invention are the same as those of related technologies, and can be referred to the foregoing description, so they will not be repeated here.

[0039] Specifically, this embodiment of the invention adds a controller 9, a tension sensor 4, and a torque compensation unit 3 to the hoist braking control system, thereby solving the aforementioned problem of heavy-load hook slippage. The controller 9 is communicatively connected to the tension sensor 4. The tension sensor 4 detects the mass or gravity of the load lifted by the crane. The lifted load is indirectly applied to the wire rope through components such as the hook. The tension sensor 4 measures the tension in the wire rope, and the mass and gravity of the lifted load can be calculated (this method is known technology and will not be elaborated here). After receiving the data from the tension sensor 4, the controller 9 determines whether the load is overloaded. For example, it compares the detected tension with a preset force threshold. If the detected tension is greater than the preset force threshold, the load is considered overloaded; if the detected tension is not greater than the preset force threshold, the load is considered not overloaded. The controller 9 can be a central processing unit, a network processor, or a combination thereof. The controller 9 may further include a hardware chip, which can be an application-specific integrated circuit (ASIC), a programmable logic device (PLD), or a combination thereof. The PLD can be a complex programmable logic device (CPL), a field-programmable gate array (FPGA), a general-purpose array logic (GPRS), or any combination thereof.

[0040] When the controller 9 determines that the load is not overloaded, the problem of hook slippage under heavy load will not occur. The hydraulic control directional valve 2 can be controlled according to the conventional control process. The specific control process can be referred to the description of the relevant technologies mentioned above, and will not be repeated here. When the load is overloaded, in order to prevent the hook from slipping under heavy load, the controller 9 provided in this embodiment of the invention controls the torque compensation unit 3 to apply a compensation force to the spring end of the hydraulic directional valve 2, increasing the resistance of the hydraulic pilot end of the hydraulic directional valve 2, thereby causing the shuttle valve 7 to output more oil, so that the hydraulic pilot end of the hydraulic directional valve 2 can build up greater pressure, which can drive the hydraulic directional valve 2 to change its working position, and prolong the time for the hydraulic directional valve 2 to switch from the second working position to the first working position. During this extended time t, the pressure build-up time of the lifting port of the hydraulic motor 0 is also extended by t, thereby increasing the lifting force. When the hydraulic directional valve 2 is opened, the locking of the winch brake 1 is released. After the hydraulic motor 0 has built up pressure for time t, it will not fall instantly due to insufficient pressure at the lifting port of the hydraulic motor 0 under heavy load (excessive gravity). Thus, the hydraulic motor 0 of the lifting system can stably output lifting force to hold the load, avoiding the problem of hook slippage under heavy load caused by directly releasing the winch brake 1.

[0041] In some alternative embodiments, the torque compensation unit 3 may include a motor (not shown) and a rack (not shown). The motor is communicatively connected to the controller 9, and the rack is connected to the motor shaft via gears. The motor controls the movement of the rack by rotation. Thus, the rotational torque can be converted into a horizontal torque by rotating the motor, thereby controlling the extension and retraction of the gear. Furthermore, one end of the rack faces the spring end of the hydraulic directional valve 2.

[0042] Specifically, through the torque compensation unit 3 provided in this embodiment of the invention, when the controller 9 determines that a compensation force needs to be applied to the spring end of the hydraulic directional valve 2, the gear extends through the rotation of the motor and contacts the spring end of the hydraulic directional valve 2, thereby providing a compensation force to the spring end of the hydraulic directional valve 2, increasing the resistance when the hydraulic directional valve 2 switches working positions, and achieving the effect of delayed start.

[0043] In other alternative implementations, such as Figure 4 As shown, the torque compensation unit 3 is installed in the return oil branch; wherein the torque compensation unit 3 includes a first electromagnetic directional valve 3a and an overflow valve 3b. The control end of the first electromagnetic directional valve 3a is communicatively connected to the controller 9. The input end of the first electromagnetic directional valve 3a is connected to the return oil end pipeline of the hydraulic directional valve 2. The first output end of the first electromagnetic directional valve 3a is connected to the oil tank 6 pipeline. The second output end of the first electromagnetic directional valve 3a is connected to the input end pipeline of the overflow valve 3b. The output end of the overflow valve 3b is connected to the oil tank 6 pipeline. The return oil end of the hydraulic directional valve 2 is also connected to the spring end pipeline of the hydraulic directional valve 2. The first electromagnetic directional valve 3a includes a third working position and a fourth working position. The third working position is used to connect the input end and the first output end of the first electromagnetic directional valve 3a. The fourth working position is used to connect the input end and the second output end of the first electromagnetic directional valve 3a.

[0044] The technical solution provided by this invention provides another method for torque compensation using hydraulic fluid. The controller 9 is communicatively connected to the tension sensor 4. The tension sensor 4 detects the tension value of the load lifted by the crane. After acquiring the data, the controller 9 determines whether the load is overloaded. For example, it compares the detected tension with a preset force threshold. If the detected tension is greater than the preset force threshold, the load is determined to be overloaded; if the detected tension is not greater than the preset force threshold, the load is determined to be within the acceptable range.

[0045] When the load is not excessive, the problem of hook slippage under heavy load will not occur. At this time, the controller 9 keeps the first solenoid directional valve 3a in the third working position, so that the input end and the first output end of the first solenoid directional valve 3a are connected, so that the return oil of the winch brake 1 flows directly into the oil tank 6 through the hydraulic directional valve 2. Then, the hydraulic directional valve 2 can be controlled according to the conventional control process.

[0046] When the load is overloaded, to prevent the hook from slipping under heavy load, the controller 9 switches the first solenoid directional valve 3a from the third working position to the fourth working position. This connects the input and output terminals of the first solenoid directional valve 3a, so the return oil from the winch brake 1 must first flow to the relief valve 3b through the hydraulic directional valve 2. Only after overcoming the spring back pressure of the relief valve 3b can the relief valve 3b open, allowing the return oil to be further output to the oil tank 6. Because the return oil terminal of the hydraulic directional valve 2 is also connected to the spring terminal of the hydraulic directional valve 2, the back pressure of the relief valve 3b can act on the spring terminal of the hydraulic directional valve 2, thereby applying a compensating force to the spring terminal of the hydraulic directional valve 2. This increases the resistance of the hydraulic pilot terminal of the hydraulic directional valve 2, causing the shuttle valve 7 to output more oil to drive the hydraulic directional valve 2 to change its working position, thus extending the time for the hydraulic directional valve 2 to switch from the second working position to the first working position.

[0047] In some alternative implementations, such as Figure 5 As shown, the hoist braking control system provided by the present invention also includes a solenoid valve 10, which is disposed between the lifting control device 12 and the hydraulic pilot end of the hydraulic directional valve 2, specifically... Figure 5 For example, solenoid valve 10 is located between the output end of shuttle valve 7 and the hydraulic pilot end of hydraulic directional valve 2. Solenoid valve 10 is communicatively connected to controller 9, and controller 9 is communicatively connected to tension sensor 4. Tension sensor 4 is used to detect the force exerted by the weight on the wire rope.

[0048] Specifically, this embodiment of the invention also provides another method for delayed activation of the hydraulic directional valve 2. This is achieved by installing a solenoid valve 10 between the lifting control device 12 and the hydraulic pilot end of the hydraulic directional valve 2, and then communicating the solenoid valve 10 with the controller 9. The solenoid valve 10 acts as a switch. If the tension sensor 4 detects that the current load is relatively light, the controller 9 can wait a short time (a first preset time) before opening the solenoid valve 10. If the tension sensor 4 detects that the current load is heavy, the controller 9 can wait for a longer period of time (the second preset time) before opening the solenoid valve 10, thereby connecting the lifting control device 12 with the hydraulic pilot end of the hydraulic directional valve 2. If the waiting time is not longer, the solenoid valve 10 will not be opened, and the oil output by the lifting control device 12 (in this embodiment, the oil output by the shuttle valve 7 is taken as an example) cannot enter the hydraulic pilot end of the hydraulic directional valve 2, thus preventing control of the hydraulic directional valve 2. The second preset time is longer than the first preset time, which also achieves the effect of delayed start of the hydraulic directional valve 2, ensuring that the lifting system has been adjusted when the hydraulic directional valve 2 is opened. Even if the locking of the winch brake 1 is released, the lifting system can stably hold the load, thereby avoiding the problem of heavy-load hook slippage caused by directly releasing the winch brake 1.

[0049] In some alternative implementations, such as Figure 6 As shown, solenoid valve 10 is a second solenoid directional valve 11. The output end of the second solenoid directional valve 11 is connected to the hydraulic pilot end pipeline of the hydraulic directional valve 2. The first input end of the second solenoid directional valve 11 is connected to the return oil branch. The second input end of the second solenoid directional valve 11 is connected to the lifting control device 12 pipeline. The spring end of the hydraulic directional valve 2 is connected to the return oil branch. The control end of the second solenoid directional valve 11 is communicatively connected to the controller 9. The second solenoid directional valve 11 includes a fifth working position and a sixth working position. The fifth working position is used to connect the first input end and the output end of the second solenoid directional valve 11, and the sixth working position is used to connect the second input end and the output end of the second solenoid directional valve 11.

[0050] Specifically, the present invention uses a second electromagnetic reversing valve 11 as an electromagnetic valve 10, which acts as a switch between the lifting control device 12 and the hydraulic pilot end of the hydraulic reversing valve 2. Figure 6 Taking the lifting control device 12, composed of shuttle valve 7 and hydraulic control handle 8, as an example, when it is not necessary for the output end of shuttle valve 7 to be connected to the hydraulic control pilot end of hydraulic control directional valve 2, the second electromagnetic directional valve 11 is controlled to be in the fifth working position. When it is necessary for the output end of shuttle valve 7 to be connected to the hydraulic control pilot end of hydraulic control directional valve 2, the second electromagnetic directional valve 11 is switched to the sixth working position. Based on this, if the tension sensor 4 detects that the current load is a heavy load, the controller 9 can wait for a relatively long time to switch the second electromagnetic directional valve 11 from the fifth working position to the sixth working position, thereby connecting the output end of shuttle valve 7 to the hydraulic control pilot end of hydraulic control directional valve 2. If no relatively long waiting time is observed, the fifth working position remains unchanged, and the oil output by shuttle valve 7 cannot enter the hydraulic control pilot end of hydraulic control directional valve 2, thus preventing control of hydraulic control directional valve 2, achieving the same effect of delayed start of hydraulic control directional valve 2.

[0051] It should be noted that in this embodiment, the first input end of the second electromagnetic directional valve 11 is connected to the return oil branch, and the spring end of the hydraulic directional valve 2 is also connected to the return oil branch. The purpose is to ensure that when the winch brake 1 returns oil to the oil tank 6, the oil pressure at both ends of the hydraulic directional valve 2 remains balanced, and the hydraulic directional valve 2 can be stably in the current working position to prevent the hydraulic directional valve 2 from shaking.

[0052] According to an embodiment of the present invention, a hoist braking control method embodiment is provided. It should be noted that the steps shown in the flowchart in the accompanying drawings can be executed in a computer system such as a set of computer-executable instructions. Furthermore, although a logical order is shown in the flowchart, in some cases, the steps shown or described may be executed in a different order than that shown here.

[0053] This embodiment provides a hoist braking control method, which can be used in the aforementioned controller. Figure 7 This is a flowchart of a hoist braking control method according to an embodiment of the present invention, the flowchart including the following steps:

[0054] Step S601: When the hydraulic handle is operated, the tension value is detected by the tension sensor;

[0055] Step S602: When the tension value is greater than the preset force threshold, the spring end of the hydraulic control directional valve is compensated by the torque compensation unit.

[0056] The control principle of the above steps has been described in the foregoing system embodiments, and can be referred to the foregoing system embodiments, and will not be repeated here.

[0057] In some alternative implementations, step S602 includes:

[0058] Step a1: Control the motor to rotate so as to push the rack toward the spring end of the hydraulic directional valve, so that the rack applies a thrust to the spring end of the hydraulic directional valve.

[0059] In some alternative implementations, step S602 includes:

[0060] Step b1: Control the first solenoid directional valve to switch from the third working position to the fourth working position.

[0061] In some optional embodiments, the hoist braking control method provided by the present invention further includes:

[0062] Step c1: When the tension value is less than or equal to the preset force threshold, the solenoid valve is opened after the first preset time so that the output end of the lifting control device is connected to the hydraulic pilot end of the hydraulic directional valve.

[0063] Step c2: When the tension value is greater than the preset force threshold, the solenoid valve is opened after a second preset time so that the output end of the lifting control device is connected to the hydraulic pilot end of the hydraulic directional valve. The second preset time is greater than the first preset time.

[0064] In some alternative implementations, step c1 includes:

[0065] Step c11: When the tension value is less than or equal to the preset force threshold, the second electromagnetic reversing valve is switched from the fifth working position to the sixth working position after the first preset time.

[0066] In some alternative implementations, step c2 includes:

[0067] Step c21: When the tension value is greater than the preset force threshold, the second electromagnetic directional valve is switched from the fifth working position to the sixth working position after the second preset time.

[0068] The control principle of the above steps has been described in the foregoing system embodiments, and can be referred to the foregoing system embodiments, and will not be repeated here.

[0069] This invention also provides a crane, including a vehicle body, a hook, a winch, and a winch braking control system provided in the aforementioned system embodiments. The winch is mounted on the vehicle body, and the winch's wire rope is connected to the hook. The hook is suspended from the far end of the lifting boom of the vehicle body via the wire rope. The winch braking control system is located within the vehicle body, and the hydraulic motor in the winch braking control system is connected to the winch's drive shaft.

[0070] This invention also provides a computer-readable storage medium. The methods described above according to embodiments of the invention can be implemented in hardware or firmware, or implemented as computer code that can be recorded on a storage medium, or implemented as computer code downloaded via a network and originally stored on a remote storage medium or a non-transitory machine-readable storage medium and then stored on a local storage medium. Thus, the methods described herein can be processed by software stored on a storage medium using a general-purpose computer, a dedicated processor, or programmable or dedicated hardware. The storage medium can be a magnetic disk, optical disk, read-only memory, random access memory, flash memory, hard disk, or solid-state drive, etc.; further, the storage medium can also include combinations of the above types of memory. It is understood that computers, processors, microprocessor controllers, or programmable hardware include storage components capable of storing or receiving software or computer code, which, when accessed and executed by the computer, processor, or hardware, implements the methods shown in the above embodiments.

[0071] A portion of this invention can be applied as a computer program product, such as computer program instructions, which, when executed by a computer, can invoke or provide the methods and / or technical solutions according to the invention through the operation of the computer. Those skilled in the art will understand that the forms in which computer program instructions exist in a computer-readable medium include, but are not limited to, source files, executable files, installation package files, etc. Correspondingly, the ways in which computer program instructions are executed by a computer include, but are not limited to: the computer directly executing the instructions, or the computer compiling the instructions and then executing the corresponding compiled program, or the computer reading and executing the instructions, or the computer reading and installing the instructions and then executing the corresponding installed program. Here, the computer-readable medium can be any available computer-readable storage medium or communication medium accessible to a computer.

[0072] Although embodiments of the invention have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the invention, and such modifications and variations all fall within the scope defined by the appended claims.

Claims

1. A hoist braking control system, characterized in that, include: The system comprises a hydraulic motor, a winch brake, a hydraulically controlled directional valve, an oil tank, an oil pump, a lifting control device, a controller, a tension sensor, and a torque compensation unit. The hydraulic motor drives the winch. The piston rod of the winch brake abuts against the output shaft of the hydraulic motor to control its rotation. The winch brake is connected to the hydraulically controlled directional valve via a pipeline. The hydraulically controlled directional valve is connected to the oil pump via a supply branch pipeline, and to the oil tank via a return branch pipeline. The oil pump is also connected to the oil tank via a pipeline. The hydraulically controlled directional valve controls the opening and closing of the supply and return oil paths. The hydraulically controlled pilot end of the hydraulically controlled directional valve is connected to the lifting control device. The torque compensation unit is connected to the spring end of the hydraulically controlled directional valve, and is communicatively connected to the controller. The controller is communicatively connected to the tension sensor, which detects the tension of the load acting on the wire rope. The torque compensation unit includes a motor and a rack. The motor is communicatively connected to the controller. The rack is connected to the motor shaft via gears. One end of the rack faces the spring end of the hydraulic directional valve. The motor is used to control the rack to move toward the spring end of the hydraulic directional valve by rotation. One end of the rack is used to provide compensation force by abutting against the spring end of the hydraulic directional valve.

2. The hoist braking control system according to claim 1, characterized in that, The torque compensation unit is disposed in the return oil branch; wherein the torque compensation unit includes a first electromagnetic directional valve and a relief valve, the control terminal of the first electromagnetic directional valve is communicatively connected to the controller, the input terminal of the first electromagnetic directional valve is connected to the return oil end pipeline of the hydraulic directional valve, the first output terminal of the first electromagnetic directional valve is connected to the oil tank pipeline, the second output terminal of the first electromagnetic directional valve is connected to the input terminal pipeline of the relief valve, the output terminal of the relief valve is connected to the oil tank pipeline, and the return oil end of the hydraulic directional valve is also connected to the spring end pipeline of the hydraulic directional valve; the first electromagnetic directional valve includes a third working position and a fourth working position, the third working position is used to connect the input terminal and the first output terminal of the first electromagnetic directional valve, and the fourth working position is used to connect the input terminal and the second output terminal of the first electromagnetic directional valve.

3. The hoist braking control system according to claim 1, characterized in that, It also includes a solenoid valve, which is disposed between the lifting control device and the hydraulic pilot end of the hydraulic directional valve. The solenoid valve is communicatively connected to the controller, and the controller is communicatively connected to the tension sensor.

4. The hoist braking control system according to claim 3, characterized in that, The solenoid valve is a second solenoid directional valve. The output end of the second solenoid directional valve is connected to the hydraulic pilot end pipeline of the hydraulic directional valve. The first input end of the second solenoid directional valve is connected to the return oil branch. The second input end of the second solenoid directional valve is connected to the output end pipeline of the lifting control device. The spring end of the hydraulic directional valve is connected to the return oil branch. The control end of the second solenoid directional valve is communicatively connected to the controller. The second solenoid directional valve includes a fifth working position and a sixth working position. The fifth working position is used to connect the first input end and the output end of the second solenoid directional valve, and the sixth working position is used to connect the second input end and the output end of the second solenoid directional valve.

5. A hoist braking control method, characterized in that, Applied to a controller, said controller being the controller in the hoist braking control system provided in any one of claims 1-4, comprising: When the hydraulic handle is operated, the tension value is detected by the tension sensor; When the tension value is greater than the preset force threshold, the torque compensation unit compensates the spring end of the hydraulic directional valve.

6. The method according to claim 5, characterized in that, The torque compensation of the spring end of the hydraulic directional valve via the torque compensation unit includes: Control the first solenoid directional valve to switch from the third working position to the fourth working position.

7. The method according to claim 5, characterized in that, Also includes: When the tension value is less than or equal to the preset force threshold, the solenoid valve is opened after a first preset time so that the output end of the lifting control device is connected to the hydraulic pilot end of the hydraulic directional valve. When the tension value is greater than the preset force threshold, the solenoid valve is opened after a second preset time so that the output end of the lifting control device is connected to the hydraulic pilot end of the hydraulic directional valve, and the second preset time is greater than the first preset time.

8. The method according to claim 7, characterized in that, The step of opening the solenoid valve after a first preset time when the tension value is less than or equal to the preset force threshold includes: When the tension value is less than or equal to the preset force threshold, the second electromagnetic reversing valve is switched from the fifth working position to the sixth working position after a first preset time.

9. The method according to claim 7, characterized in that, The step of opening the solenoid valve after a second preset time when the tension value is greater than the preset force threshold includes: When the tension value is greater than the preset force threshold, the second electromagnetic reversing valve is switched from the fifth working position to the sixth working position after a second preset time.

10. A crane, characterized in that, The system includes a vehicle body, a hook, a winch, and a winch braking control system as provided in any one of claims 1-4. The winch is mounted on the vehicle body, and the wire rope of the winch is connected to the hook. The hook is suspended from the far end of the boom of the vehicle body via the wire rope. The winch braking control system is located within the vehicle body, and the hydraulic motor in the winch braking control system is connected to the drive shaft of the winch.

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