Crane steering system based on driving, control method thereof and crane

Abstract

The present invention provides a crane steering system and a control method thereof based on driving. The crane steering system and the control method thereof can be used for new energy architecture and fuel architecture. The crane steering system includes an oil supply mechanism, a steering machine, a first circuit, a second circuit, at least two steering mechanisms, at least two steering axles, at least two first detection devices and a control device. The steering machine is connected to the oil supply mechanism, one end of the first circuit and one end of the second circuit are respectively connected to the steering machine, and the other end thereof is respectively connected to each steering mechanism. Each first detection device is respectively arranged on each steering mechanism or each steering axle. When the steering axle is in a suspended state, the first detection device detects a first signal and transmits it to the control device. The control device controls the oil supply of the oil supply mechanism to reduce the circuit pressure of the crane steering system. The crane steering system of the present invention can determine whether the steering axle is in a suspended state. The present invention also relates to a crane.

Description

Technical Field

[0001] The present invention relates to the technical field of engineering machinery, and in particular to a steering system of a crane during driving, a control method thereof, and a crane. Background Art

[0002] As truck cranes develop towards larger sizes and multiple working conditions, not only are their driving states increasing, but also due to intensified product competition, road driving conditions and construction sites are becoming increasingly severe. Users are constantly improving their requirements for product driving capabilities and adaptability to all road surfaces. Therefore, it is becoming increasingly important to ensure the driving safety of products on various extreme roads.

[0003] According to the current development trend of engineering vehicles, the development of vehicles with new energy architecture has reached a certain scale. Existing crane products basically use hydraulic and electronically controlled power steering systems. The steering system includes a steering oil pump, a steering gear, a steering valve, a steering power cylinder, a steering mechanism and connecting oil pipes. The steering power cylinder is installed on the steering axle and connected to the steering gear through structural parts such as a ball head. When the vehicle is driving, the high-pressure oil generated by the steering oil pump controls the pressure, flow rate and flow rate entering the steering power cylinder through the valve to promote the movement of the steering mechanism, thereby driving the tires on the steering axle to rotate and realize the steering of the vehicle. However, in this system, the oil pressure in the steering power cylinders connected to the same circuit through pipelines is the same, and the oil pressure is determined by the actual load of the steering axle (the actual load is fed back in real time through the pressure of the suspension cylinder connected to the steering axle). When the vehicle is driving, if the tires on some steering axles are suspended due to road or suspension system failure, the axle load that should be borne on the steering axle will be transferred to the remaining steering axles, thereby increasing the pressure in the suspension cylinders on the remaining steering axles, causing the oil pressure of all steering power cylinders entering the same circuit to increase to push the steering cylinder to move, and simultaneously drive the steering mechanism to push the steering wheel to move. However, since the tires of the suspended steering axle are not under force, the huge thrust generated by the steering power cylinder can only act on the steering mechanism, thereby causing damage to the steering mechanism. Summary of the invention

[0004] In view of this, an object of the present invention is to provide a crane steering system based on driving, which can solve the problems existing in the prior art, determine whether the steering bridge is in a suspended state, and avoid damage to the steering mechanism.

[0005] The present invention provides a steering system for a crane during driving, comprising an oil supply mechanism, a steering gear, a first circuit, a second circuit, at least two steering mechanisms, at least two steering axles, at least two first detection devices and a control device, wherein the steering gear is connected to the oil supply mechanism, one end of the first circuit and one end of the second circuit are respectively connected to the steering gear, the other end of the first circuit and the other end of the second circuit are respectively connected to each of the steering mechanisms, each of the first detection devices is respectively arranged on each of the steering mechanisms or each of the steering axles, the first detection device is used to detect the extreme position of the steering mechanism, each of the first detection devices is respectively electrically connected to the control device, and a signal of the steering mechanism being located at the extreme turning angle position detected by the first detection device is defined as a first signal, if the first signal is transmitted to the control device, the steering axle is in a suspended state, and the control device controls the oil supply of the oil supply mechanism to reduce the circuit pressure of the crane steering system.

[0006] In one embodiment, the crane steering system further includes a first pressure sensor and a second pressure sensor, wherein the first pressure sensor is disposed on the first circuit and is used to detect the oil pressure of the first circuit, and the second pressure sensor is disposed on the second circuit and is used to detect the oil pressure of the second circuit, and the circuit pressure is the oil pressure of the first circuit or the oil pressure of the second circuit.

[0007] In one embodiment, when the steering mechanism detected by the first detection device is not in the extreme turning angle position, the control device compares the circuit pressure with the maximum pressure that the crane steering system can withstand. When the circuit pressure is less than or equal to the maximum pressure that the crane steering system can withstand, the vehicle drives normally.

[0008] In one embodiment, the crane steering system further includes a suspension cylinder and a second detection device, wherein the suspension cylinder is communicated with the oil supply mechanism, the suspension cylinder is connected between the vehicle frame and the steering axle, and the second detection device is arranged on the suspension cylinder, and the second detection device is used to detect the stroke of the suspension cylinder. When the circuit pressure is greater than the maximum pressure that the crane steering system can withstand, and the second detection device detects a signal indicating the maximum stroke position of the suspension cylinder, the steering axle is in a suspended state, and the control device controls the oil supply of the oil supply mechanism to reduce the circuit pressure; or when the circuit pressure is greater than the maximum pressure that the crane steering system can withstand, and the second detection device does not detect a signal indicating that the suspension cylinder is in the maximum stroke position, the vehicle travels normally.

[0009] In one embodiment, the crane steering system further comprises an alarm device, wherein the alarm device is electrically connected to the control device, and when the steering bridge is in a suspended state, the alarm device is activated.

[0010] In one embodiment, the oil supply mechanism includes a hydraulic oil tank, a steering oil pump and an electric control valve, and the electric control valve is connected to the steering oil pump and the hydraulic oil tank through a pipeline.

[0011] The present invention also relates to a control method for the above-mentioned crane steering system based on driving, the control method comprising:

[0012] The signal of the steering mechanism is obtained through the first detection device. When the first signal is obtained, the control device determines that the steering axle is in a suspended state, the alarm device sounds an alarm, and the control device controls the electric control valve to unload to reduce the circuit pressure so that the circuit pressure is less than the system back pressure.

[0013] In one embodiment, a signal of the steering mechanism is obtained by a first detection device. When the first signal is not obtained, the circuit pressure is compared with the maximum pressure that the crane steering system can withstand. If the circuit pressure is less than or equal to the maximum pressure that the crane steering system can withstand, the control device determines that the vehicle is driving normally; if the circuit pressure is greater than the maximum pressure that the crane steering system can withstand, the control device determines the posture of the steering axle based on the signal of the second detection device.

[0014] In one embodiment, when the second detection device detects a signal that the suspension cylinder is in the maximum stroke position, the control device determines that the steering axle is in a suspended state, the alarm device alarms, and the control device controls the electronically controlled valve to unload to reduce the circuit pressure so that the circuit pressure is less than or equal to the circuit pressure required for normal steering at the maximum driving weight.

[0015] The present invention also relates to a crane, comprising the above-mentioned crane steering system based on driving.

[0016] The crane steering system of the present invention is provided with a first detection device on each steering mechanism or each steering axle. The first detection device is used to detect the extreme position of the steering mechanism. The first signal of the first detection device can be used to determine whether the steering axle is in a suspended state. The control device controls the supply of the oil supply mechanism to reduce the circuit pressure of the crane steering system, thereby protecting the steering mechanism and the steering axle and avoiding damage to the steering mechanism due to excessive thrust. The crane steering system is not only suitable for new energy power drive, but also for fuel power drive. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments are briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without creative work.

[0018] Figure 1 It is a structural schematic diagram of a crane steering system according to a first embodiment of the present invention.

[0019] Figure 2 Schematic diagram of a control device according to a first embodiment of the present invention.

[0020] Figure 3 Schematic diagram of control of a crane steering system according to a first embodiment of the present invention.

[0021] Description of the drawings: oil supply mechanism-11; hydraulic oil tank-111; steering oil pump-112; electric control valve-113; steering gear-12; first circuit-13; second circuit-14; steering mechanism-15; connecting rod structure-151; first rocker arm-152; steering power cylinder-153; steering axle-16; axle body-161; first roller-162; second roller-163; first detection device-17; first pressure sensor-181; second pressure sensor-182.

[0022] The realization of the purpose, functional features and advantages of the present invention will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0023] The specific embodiments of the present invention will be described in detail below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments. Based on the description of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0024] In the description of the present invention, unless otherwise clearly specified and limited, the terms "set", "install", "connect" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms can be understood according to specific circumstances.

[0025] The directions or positional relationships indicated by terms such as “upper”, “lower”, “left”, “right”, “front”, “back”, “top”, “bottom”, “inside” and “outside” are based on the directions or positional relationships shown in the accompanying drawings, or are the directions or positional relationships in which the inventive product is usually placed when used. They are only for the convenience of description and simplified description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore should not be understood as a limitation on the present invention.

[0026] The terms "first", "second", "third" and the like are merely used to distinguish elements of similar nature, and do not indicate or imply relative importance or a particular order.

[0027] The terms "comprises," "comprising," or any other variations thereof, are intended to cover a non-exclusive inclusion of the elements listed and may also include additional elements not expressly listed.

[0028] First embodiment

[0029] like Figures 1 to 3As shown, the crane steering system based on driving in this embodiment is applicable to new energy vehicles and fuel vehicles, wherein the new energy vehicles include but are not limited to pure electric, extended-range electric, hybrid, fuel battery electric or hydrogen engines, etc. The crane steering system based on driving includes an oil supply mechanism 11, a steering gear 12, a first circuit 13, a second circuit 14, at least two steering mechanisms 15, at least two steering axles 16, at least two first detection devices 17 and a control device, the steering gear 12 is connected to the oil supply mechanism 11, one end of the first circuit 13 and one end of the second circuit 14 are respectively connected to the steering gear 12, the other end of the first circuit 13 and the other end of the second circuit 14 are respectively connected to each steering mechanism 15, the steering mechanism 15 includes a connecting rod structure 151, two rocker arms and a steering The steering power cylinder 153 and the two ends of the connecting rod structure 151 are respectively connected to the rocker arm, the rocker arm is connected to the steering axle 16, the steering power cylinder 153 is connected between the rocker arm and the bridge body 161 of the steering axle 16, and the steering power cylinder 153 can drive the rocker arm to drive the steering axle 16 to change direction. Each first detection device 17 is respectively arranged on each steering mechanism 15 or each steering axle 16. The first detection device 17 is used to detect the extreme position of the steering mechanism 15. Each first detection device 17 is electrically connected to the control device respectively. The signal of the steering mechanism 15 detected by the first detection device 17 at the extreme turning angle position is defined as the first signal. If the first signal is transmitted to the control device, the steering axle 16 is in a suspended state, and the control device controls the oil supply of the oil supply mechanism 11 to reduce the circuit pressure of the crane steering system.In this embodiment, the first detection device 17 is preferably a position sensor or a proximity switch. Taking the position sensor as an example, when the position sensor detects that the steering mechanism 15 is at the extreme turning angle position relative to the steering bridge 16, the position sensor is in the on state and sends a first signal. After the control device (PLC) receives the first signal, the control device controls the electronically controlled unloading valve to reduce the circuit pressure so that the circuit pressure P is less than the system back pressure P0 of the crane steering system, that is, P<P0; wherein the steering bridge 16 includes a bridge body 161, a first roller 162 and a second roller 163, the bridge body 161 is connected between the first roller 162 and the second roller 163, the first roller 162 and the second roller 163 are respectively connected to the bridge body 161 through a steering knot, and the two rocker arms of the steering mechanism 15 They are the first rocker arm 152 and the second rocker arm respectively. The first rocker arm 152 is used as an example for description. The steering knot between the first roller 162 and the bridge body 161 is defined as the first steering knot. The first steering knot, the first rocker arm 152 and the bridge body 161 are connected by a kingpin. The bridge body 161 and the first steering knot are movable, and the first steering knot and the first rocker arm 152 are fixed. Therefore, the steering angle is obtained by testing the angle of the first steering knot, and the steering angle is the steering angle of the steering mechanism 15. Therefore, the first detection device 17 can be set at the first rocker arm 152, the first steering knot or the steering bridge 16. The end of the steering bridge 16 close to the second roller 163 is also designed as described above. The structural design of other steering bridges 16 is also as described above, and no further details are given here. It can be understood that in this embodiment, the first circuit 13, the second circuit 14 and the pipelines connected to the first circuit 13 and the second circuit 14 are all oil pipelines. Among them, when there is a pit on the ground or the steering angle is too large, the steering bridge 16 will appear in a suspended state.

[0030] The crane steering system of the present invention is provided with a first detection device 17 on each steering mechanism 15 or each steering axle 16. The first detection device 17 is used to detect the extreme position of the steering mechanism 15. The first signal of the first detection device 17 can be used to determine whether the steering axle 16 is in a suspended state. The control device controls the supply of the oil supply mechanism 11 to reduce the circuit pressure of the crane steering system, thereby protecting the steering mechanism 15 and the steering axle 16 and preventing the steering mechanism 15 from being damaged due to excessive thrust. The crane steering system is not only suitable for new energy power drive, but also for fuel power drive.

[0031] Preferably, the oil supply mechanism 11 includes a hydraulic oil tank 111, a steering oil pump 112 and an electric control valve 113. The electric control valve 113 is connected to the steering oil pump 112 and the hydraulic oil tank 111 through a pipeline. The steering oil pump 112 is used to pump the oil in the hydraulic oil tank 111 to transport the oil to the first circuit 13 and the second circuit 14.

[0032] Preferably, the crane steering system further includes an alarm device, which is electrically connected to the control device, and is activated when the steering bridge 16 is in a suspended state. The alarm device is arranged in the cab, and the alarm device is, for example, a voice alarm, a signal indicator light or a fault code, and when the steering bridge 16 is in a suspended state, the alarm device sounds an alarm to prompt the operator to perform corresponding processing.

[0033] Preferably, the crane steering system further comprises a first pressure sensor 181 and a second pressure sensor 182. The first pressure sensor 181 is arranged on the first circuit 13 and is used to detect the oil pressure of the first circuit 13. The second pressure sensor 182 is arranged on the second circuit 14 and is used to detect the oil pressure of the second circuit 14. The circuit pressure is the oil pressure of the first circuit 13 or the oil pressure of the second circuit 14. The first pressure sensor 181 is preferably arranged at one end of the first circuit 13 close to the steering gear 12, and the second pressure sensor 182 is preferably arranged at one end of the second circuit 14 close to the steering gear 12. When the steering mechanism 15 detected by the first detection device 17 is not at the extreme turning angle position, that is, the first detection device 17 is in the disconnected state, and the first detection device 17 does not output the first signal, the control device compares the circuit pressure with the maximum pressure that the crane steering system can withstand. When the circuit pressure P is less than or equal to the maximum pressure PM that the crane steering system can withstand, that is, P≤PM, the control device issues a command for the vehicle to travel normally.

[0034] Preferably, the crane steering system also includes a suspension cylinder and a second detection device, the suspension cylinder is connected to the oil supply mechanism 11, the suspension cylinder is connected between the frame and the steering axle 16, the second detection device is arranged on the suspension cylinder, and the second detection device is used to detect the stroke of the suspension cylinder, wherein the second detection device is preferably a position sensor or a proximity switch, when the circuit pressure is greater than the maximum pressure that the crane steering system can withstand, that is, P>PM, and the second detection device detects the signal of the maximum stroke position of the suspension cylinder, that is, the second detection device is in the on state, then the control device determines that the steering axle 16 is in a suspended state, and the control device controls the oil supply of the oil supply mechanism 11 through electronic unloading to reduce the circuit pressure to P≤P1, and at the same time, an alarm is issued in the cab to prompt the operator to take corresponding measures; wherein, P1 refers to the circuit pressure required for normal steering of the vehicle at the maximum driving weight.

[0035] Preferably, when the circuit pressure is greater than the maximum pressure that the crane steering system can withstand and the second detection device does not detect a signal that the suspension cylinder is in the maximum stroke position, that is, the second detection device is in a disconnected state, the controller issues an instruction for the vehicle to travel normally.

[0036] Second embodiment

[0037] like Figures 1 to 3 As shown, this embodiment relates to a control method, which is used for the above-mentioned crane steering system based on driving, and the control method includes:

[0038] The signal of the steering mechanism 15 is obtained by the first detection device 17. When the first signal is obtained, that is, when the first detection device 17 detects that the steering mechanism 15 is located at the extreme turning angle position, the first detection device 17 is in the on state and sends a first signal to the control device. The control device determines that the steering axle 16 is in a suspended state, and the alarm device sounds an alarm. The control device controls the electric control valve 113 to unload to reduce the circuit pressure so that the circuit pressure is less than the system back pressure, that is, P<P0.

[0039] Preferably, the signal of the steering mechanism 15 is obtained by the first detection device 17. When the steering mechanism 15 detected by the first detection device 17 is not at the extreme turning angle position, that is, the first detection device 17 is in the disconnected state, the first detection device 17 does not output the first signal, and the control device does not obtain the first signal, the control device compares the circuit pressure with the maximum pressure that the crane steering system can withstand. If the circuit pressure is less than or equal to the maximum pressure that the crane steering system can withstand, the control device issues a command for the vehicle to travel normally.

[0040] If the circuit pressure is greater than the maximum pressure that the crane steering system can withstand, the control device determines the posture of the steering axle 16 based on the signal of the second detection device; when the second detection device detects the signal that the suspension cylinder is in the maximum stroke position, that is, the second detection device is in the on state, the control device determines that the steering axle 16 is in a suspended state, and the alarm device alarms. The control device controls the electric control valve 113 to unload to reduce the circuit pressure, so that the circuit pressure is less than or equal to the circuit pressure required for normal steering of the maximum driving weight, that is, P≤P1, and at the same time, an alarm is sounded in the cab to prompt the operator to take corresponding measures; wherein, P1 refers to the circuit pressure required for normal steering of the vehicle's maximum driving weight.

[0041] The present invention also relates to a crane, including the above-mentioned crane steering system based on driving. The crane of the present invention can be driven by fuel as power, and can also be adapted to be driven by power of new energy.

[0042] The above are only specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed by the present invention should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the attached claims.

Claims

1. A crane steering system based on driving, characterized in that: The invention comprises an oil supply mechanism (11), a steering gear (12), a first circuit (13), a second circuit (14), at least two steering mechanisms (15), at least two steering axles (16), at least two first detection devices (17) and a control device, wherein the steering gear (12) is connected to the oil supply mechanism (11), one end of the first circuit (13) and one end of the second circuit (14) are respectively connected to the steering gear (12), the other end of the first circuit (13) and the other end of the second circuit (14) are respectively connected to each of the steering mechanisms (15), and each of the first detection devices (17) is connected to the steering gear (15). The first detection device (17) is respectively arranged on each of the steering mechanisms (15) or each of the steering axles (16), and is used to detect the extreme position of the steering mechanism (15). Each of the first detection devices (17) is electrically connected to the control device. A signal indicating that the steering mechanism (15) is at the extreme turning angle position detected by the first detection device (17) is defined as a first signal. If the first signal is transmitted to the control device, the steering axle (16) is in a suspended state, and the control device controls the oil supply of the oil supply mechanism (11) to reduce the circuit pressure of the crane steering system. The crane steering system further comprises a first pressure sensor (181) and a second pressure sensor (182), wherein the first pressure sensor (181) is arranged on the first circuit (13), and the first pressure sensor (181) is used to detect the oil pressure of the first circuit (13); the second pressure sensor (182) is arranged on the second circuit (14), and the second pressure sensor (182) is used to detect the oil pressure of the second circuit (14), and the circuit pressure is the oil pressure of the first circuit (13) or the oil pressure of the second circuit (14); When the steering mechanism (15) detected by the first detection device (17) is not at the limit turning angle position, the control device compares the circuit pressure with the maximum pressure that the crane steering system can withstand, and when the circuit pressure is less than or equal to the maximum pressure that the crane steering system can withstand, the vehicle travels normally; The crane steering system further comprises a suspension cylinder and a second detection device, wherein the suspension cylinder is in communication with the oil supply mechanism (11), the suspension cylinder is connected between the vehicle frame and the steering axle (16), the second detection device is arranged on the suspension cylinder, and the second detection device is used to detect the stroke of the suspension cylinder. When the circuit pressure is greater than the maximum pressure that the crane steering system can withstand, and the second detection device detects a signal indicating the maximum stroke position of the suspension cylinder, the steering axle (16) is in a suspended state, and the control device controls the oil supply of the oil supply mechanism (11) to reduce the circuit pressure; or when the circuit pressure is greater than the maximum pressure that the crane steering system can withstand, and the second detection device does not detect a signal indicating that the suspension cylinder is in the maximum stroke position, the vehicle travels normally.

2. The crane steering system based on driving according to claim 1, characterized in that: The crane steering system also includes an alarm device, which is electrically connected to the control device and is activated when the steering bridge (16) is in a suspended state.

3. The crane steering system based on driving according to claim 2, characterized in that: The oil supply mechanism (11) comprises a hydraulic oil tank (111), a steering oil pump (112) and an electric control valve (113); the electric control valve (113) is connected to the steering oil pump (112) and the hydraulic oil tank (111) via a pipeline.

4. A control method for a crane steering system based on driving according to any one of claims 1 to 3, characterized in that: The control method comprises: A signal of the steering mechanism (15) is obtained through a first detection device (17); when the first signal is obtained, the control device determines that the steering axle (16) is in a suspended state, an alarm device sounds an alarm, and the control device controls the electric control valve (113) to unload to reduce the circuit pressure, so that the circuit pressure is less than the system back pressure.

5. The control method of the crane steering system during driving according to claim 4, characterized in that: A signal of the steering mechanism (15) is obtained by a first detection device (17); when the first signal is not obtained, the circuit pressure is compared with the maximum pressure borne by the crane steering system; if the circuit pressure is less than or equal to the maximum pressure borne by the crane steering system, the control device issues a command for the vehicle to travel normally; If the circuit pressure is greater than the maximum pressure that the crane steering system can withstand, the control device determines the posture of the steering bridge (16) based on the signal of the second detection device.

6. The control method of the crane steering system during driving according to claim 5, characterized in that: When the second detection device detects a signal that the suspension cylinder is at the maximum stroke position, the control device determines that the steering axle (16) is in a suspended state, the alarm device sounds an alarm, and the control device controls the electric control valve (113) to unload to reduce the circuit pressure, so that the circuit pressure is less than or equal to the circuit pressure required for normal steering at the maximum driving weight.

7. A crane, characterized in that: The invention comprises a crane steering system based on driving as described in any one of claims 1 to 3.

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