Safety brake system for bulk cargo loader and control method thereof

Abstract

The present invention relates to the field of vehicle safety control technology, in particular to a safety brake system for a bulk cargo loader and a control method thereof. The structural components of the present invention include an auxiliary safety device, a proportional pressure reducing valve, a hydraulic power system, an auxiliary brake cylinder, a shuttle valve, a foot brake pump, a front axle brake of an automobile and a rear axle brake of an automobile, and the auxiliary safety device includes an auxiliary safety device switch, a first distance signal acquisition device, a second distance signal acquisition device, a vehicle speed sensor and a controller. In the present invention, an auxiliary safety device is provided, and a shuttle valve is added between the foot brake pump and the front and rear axle brakes of the original braking system, the foot brake of the equipment is connected in parallel with the auxiliary brake, and the opening of the proportional pressure reducing valve is controlled by the output signal of the controller in the auxiliary safety device to adjust the brake pressure of the auxiliary brake cylinder, thereby controlling the braking force of the equipment, and realizing automatic deceleration and automatic braking of the equipment.

Description

Technical Field

[0001] The invention relates to the technical field of vehicle safety control, in particular to a safety braking system for a bulk cargo loader and a control method thereof. Background Art

[0002] Bulk cargo loaders are aircraft ground service equipment mainly used for loading and unloading bulk items such as luggage, parcels and mail. The equipment consists of a chassis assembly, an engine assembly, a belt rack assembly, a hydraulic system and an electrical system. According to the latest standards of the International Air Transport Association, bulk cargo loaders need to add an auxiliary anti-collision system, requiring that at any time when the minimum distance between the equipment and the aircraft docking point is less than 0.5 meters, the ground support equipment is automatically forced to enter a low-speed mode; when any part of the ground support equipment contacts the aircraft, the automatic stop function is activated. Since bulk cargo loaders generally use self-made chassis, the principle of their conventional braking system is to drive the front and rear axle brakes through the foot brake pump to achieve deceleration and braking of the equipment, so the braking system of existing equipment cannot achieve automatic deceleration and automatic braking of the equipment. Summary of the invention

[0003] The object of the present invention is to provide a safety braking system and a control method for a bulk cargo loader, so as to overcome the deficiencies of the aforementioned prior art and realize automatic deceleration and automatic braking of the bulk cargo loader, thereby improving the intelligence of the bulk cargo loader and the safety of its docking with an aircraft.

[0004] The technical solution adopted by the present invention to solve the technical problem is:

[0005] A safety brake system for a bulk cargo loader, characterized in that it includes an auxiliary safety device, a proportional pressure reducing valve, a hydraulic power system, an auxiliary brake cylinder, a shuttle valve, a foot brake pump, a front axle brake of a vehicle and a rear axle brake of a vehicle, wherein the auxiliary safety device includes an auxiliary safety device switch, a first distance signal acquisition device, a second distance signal acquisition device, a vehicle speed sensor and a controller, wherein the auxiliary safety device switch, the first distance signal acquisition device, the second distance signal acquisition device and the vehicle speed sensor are all electrically connected to the controller, the controller is electrically connected to the proportional pressure reducing valve, the hydraulic oil inlet end of the proportional pressure reducing valve is connected to the hydraulic power system, the hydraulic oil outlet end of the proportional pressure reducing valve is connected to the auxiliary brake cylinder, and the auxiliary brake cylinder is connected to the first oil inlet of the shuttle valve. The second oil inlet of the shuttle valve is connected to the foot brake pump, the oil outlet of the shuttle valve is connected to the front axle brake and the rear axle brake of the automobile, and the foot brake pump is also connected to the front axle brake and the rear axle brake of the automobile; the auxiliary safety device switch controls the opening and closing of the entire auxiliary safety device, the first distance signal acquisition device, the second distance signal acquisition device and the vehicle speed sensor constitute a signal acquisition system, which collects signals such as the distance between the device and the aircraft and the speed of the device. The controller processes and calculates the collected signals, and then outputs the processed signals to the proportional pressure reducing valve, controls the opening of the proportional pressure reducing valve to adjust the brake pressure of the auxiliary brake cylinder, and then allows the brake oil to enter the front and rear axle brakes through the shuttle valve to achieve braking of the equipment.

[0006] Furthermore, the first distance signal acquisition device is a radar sensor or a 3D camera, which acquires the distance signal between the bulk cargo loader and the aircraft in real time.

[0007] Furthermore, the second distance signal acquisition device is an ultrasonic sensor, which cooperates with a radar sensor or a 3D camera to accurately acquire the distance signal between the bulk cargo loader and the aircraft.

[0008] Furthermore, the auxiliary brake cylinder includes a hydraulic cylinder and an auxiliary brake pump connected to the hydraulic cylinder, the hydraulic oil outlet end of the proportional pressure reducing valve is connected to the hydraulic cylinder, the auxiliary brake pump is connected to the first oil inlet port of the shuttle valve, the hydraulic oil of the hydraulic power system enters the hydraulic cylinder after passing through the proportional pressure reducing valve, and drives the hydraulic cylinder to control the action of the auxiliary brake pump through the hydraulic oil, after the auxiliary brake pump is actuated, the brake oil enters the shuttle valve through the first oil inlet port, and enters the front axle brake and the rear axle brake of the vehicle from the shuttle valve to control the deceleration and / or braking of the vehicle.

[0009] A control method for a safety brake system for a bulk cargo loader, characterized in that: turning on an auxiliary safety device switch to start the auxiliary safety device, collecting a distance signal between the bulk cargo loader and an aircraft through the cooperation of a first distance signal acquisition device and a second distance signal acquisition device, collecting a vehicle speed signal of the bulk cargo loader through a vehicle speed sensor, and transmitting the collected distance signal and vehicle speed signal to a controller, the controller processes and calculates the received distance signal and vehicle speed signal, and then outputs the processed and calculated signal to a proportional pressure reducing valve, controls the opening of the proportional pressure reducing valve to adjust the size of the brake pressure of the auxiliary brake cylinder, thereby controlling the size of the driving force of the bulk cargo loader, and realizing automatic deceleration and automatic braking of the bulk cargo loader.

[0010] Furthermore, the control method of the safety brake system for the bulk cargo loader specifically includes the following control modes:

[0011] (1) Automatic braking deceleration control in medium speed mode

[0012] The area within the distance L1 to L2 from the aircraft is set as the medium-speed mode area, L1>L2, and the maximum speed of the bulk cargo loader in the medium-speed mode area is set to V1. Before the bulk cargo loader enters the medium-speed mode area, the auxiliary safety switch is turned on, and the auxiliary safety device is in the starting state. When it is detected that the bulk cargo loader enters the medium-speed mode area, if the actual speed of the bulk cargo loader V>V1, according to the "medium-speed mode automatic brake deceleration control" formula in the controller, the controller outputs a proportional pressure reducing valve control current signal to the proportional pressure reducing valve, and the auxiliary brake pump in the auxiliary brake cylinder is activated, and the bulk cargo loader automatically decelerates. Before the actual distance between the bulk cargo loader and the aircraft L=L2, the actual speed of the bulk cargo loader drops to V<V1, and then the system enters the medium-speed mode automatic brake deceleration control stage;

[0013] (2) Automatic braking and deceleration control in low speed mode

[0014] The area within the distance L2 to L3 from the aircraft is set as the low-speed mode area, L2>L3, and the maximum driving speed of the bulk cargo loader in the medium-speed mode is limited to V2. After the bulk cargo loader enters the low-speed mode area, if the actual speed of the bulk cargo loader V>V2, according to the "low-speed mode automatic brake deceleration control" formula in the controller, the controller outputs a proportional pressure reducing valve control current signal to the proportional pressure reducing valve, and the auxiliary brake pump in the auxiliary brake cylinder is actuated, and the bulk cargo loader automatically decelerates. Before the actual distance L between the bulk cargo loader and the aircraft is L=L3, the actual speed of the bulk cargo loader drops to V<V2, and the speed V2 is maintained to continue driving, and then the system enters the automatic brake control stage;

[0015] (3) Automatic brake control

[0016] When the actual distance between the bulk cargo loader and the aircraft is L=L3, the automatic brake control stage is immediately entered, the controller outputs the maximum proportional pressure reducing valve control current signal to the proportional pressure reducing valve, the braking force of the auxiliary brake pump in the auxiliary brake cylinder is the maximum power, and the vehicle brakes automatically.

[0017] Furthermore, the formula for "automatic braking deceleration control in medium-speed mode" is: I1=(V-V1) / (VH-V1)*(braking force M2-braking force M1), wherein: I1 is the control current of the proportional pressure reducing valve in medium-speed mode, VH is the maximum vehicle speed that the bulk cargo loader can reach, braking force M1 is the braking force setting value 1 in medium-speed mode, braking force M2 is the braking force setting value 2 in medium-speed mode, and braking force M2>braking force M1.

[0018] Furthermore, the "low-speed mode automatic braking deceleration control" formula is: I2 = (V-V2) / (V1-V2)*(braking force L2-braking force L1), wherein: I2 is the low-speed mode proportional pressure reducing valve control current, braking force L1 is the low-speed mode braking force setting value 1, braking force L2 is the low-speed mode braking force setting value 2, and braking force H2>braking force H1.

[0019] Furthermore, L1 is set to 9m, L2 is set to 3m, L3 is set to 150mm; V1 is set to 6km / h, and V2 is set to 0.8km / h.

[0020] The beneficial effect of the present invention is that compared with the prior art, the safety brake system for bulk cargo loaders of the present invention and the control method thereof have the following advantages: in order to realize automatic deceleration and braking of the equipment, an auxiliary safety device is added, and a shuttle valve is added between the foot brake pump and the front and rear axle brakes of the original braking system, the oil inlets on both sides of the shuttle valve are respectively connected to the foot brake pump and the auxiliary brake pump, and the oil outlet of the shuttle valve is connected to the front and rear axle brakes to realize the parallel connection of the equipment foot brake and the auxiliary brake, the hydraulic power system drives the hydraulic cylinder through the hydraulic oil to realize the action of the auxiliary brake pump, and after the auxiliary brake pump is actuated, the brake oil enters the front and rear axle brakes through the shuttle valve to realize the braking of the equipment, and the opening of the proportional pressure reducing valve is controlled by the output signal of the controller in the auxiliary safety device to adjust the brake pressure of the auxiliary brake cylinder, thereby controlling the braking force of the equipment and realizing automatic deceleration and automatic braking of the equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 This is a schematic diagram of the structure of Embodiment 1 of the present invention;

[0022] Figure 2 This is a logic block diagram of Embodiment 2 of the present invention;

[0023] Among them, 1 auxiliary safety device, 101 auxiliary safety device switch, 102 first distance signal acquisition equipment, 103 second distance signal acquisition equipment, 104 vehicle speed sensor, 105 controller, 2 proportional pressure reducing valve, 3 hydraulic power system, 4 auxiliary brake cylinder, 401 hydraulic cylinder, 402 auxiliary brake pump, 5 shuttle valve, 6 foot brake pump, 7 car front axle brake, 8 car rear axle brake. DETAILED DESCRIPTION

[0024] To make the purpose, technical solution and advantages of the embodiments of the present invention more clear, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention.

[0025] Example 1 Safety brake system for bulk cargo loader

[0026] like Figure 1 In the illustrated embodiment, the safety brake system for a bulk cargo loader comprises an auxiliary safety device 1, a proportional pressure reducing valve 2, a hydraulic power system 3, an auxiliary brake cylinder 4, a shuttle valve 5, a foot brake pump 6, a front axle brake 7 and a rear axle brake 8 of a vehicle, wherein the auxiliary safety device 1 comprises an auxiliary safety device switch 101, a first distance signal acquisition device 102, a second distance signal acquisition device 103, a vehicle speed sensor 104 and a controller 105, and the auxiliary safety device switch 101, the first distance signal acquisition device 102, the second distance signal acquisition device 103, a vehicle speed sensor 104 and a controller 105. The device 103 and the vehicle speed sensor 104 are both electrically connected to the controller 105, the controller 105 is electrically connected to the proportional pressure reducing valve 2, the hydraulic oil inlet end of the proportional pressure reducing valve 2 is connected to the hydraulic power system 3, the hydraulic oil outlet end of the proportional pressure reducing valve 2 is connected to the auxiliary brake cylinder 4, the auxiliary brake cylinder 4 is connected to the first oil inlet of the shuttle valve 5, the second oil inlet of the shuttle valve 5 is connected to the foot brake pump 6, the oil outlet of the shuttle valve 5 is connected to the front axle brake 7 and the rear axle brake 8 of the vehicle, and the foot brake pump 6 is also connected to the front axle brake 7 and the rear axle brake 8 of the vehicle.

[0027] In this embodiment, the first distance signal acquisition device 102 is a radar sensor or a 3D camera.

[0028] In this embodiment, the second distance signal acquisition device 103 is an ultrasonic sensor.

[0029] In this embodiment, the auxiliary brake cylinder 4 includes a hydraulic cylinder 401 and an auxiliary brake pump 402 connected to the hydraulic cylinder 401. The hydraulic oil outlet end of the proportional pressure reducing valve 2 is connected to the hydraulic cylinder 401. The auxiliary brake pump 402 is connected to the first oil inlet of the shuttle valve 5. The hydraulic oil of the hydraulic power system 3 enters the hydraulic cylinder 401 after passing through the proportional pressure reducing valve 2, and drives the hydraulic cylinder 401 through the hydraulic oil to control the action of the auxiliary brake pump 402. After the auxiliary brake pump 402 is actuated, the brake oil enters the shuttle valve 5 through the first oil inlet, and enters the front axle brake 7 and the rear axle brake 8 of the vehicle from the shuttle valve 5 to control the deceleration and / or braking of the vehicle.

[0030] The auxiliary safety device switch 101 controls the opening and closing of the entire auxiliary safety device 1. The first distance signal acquisition device 102, the second distance signal acquisition device 103 and the vehicle speed sensor 104 constitute a signal acquisition system to collect signals such as the distance between the device and the aircraft and the speed of the device. The controller 105 processes and calculates the collected signals, and then outputs the processed signals to the proportional pressure reducing valve 2, controls the opening of the proportional pressure reducing valve 2 to adjust the braking pressure of the auxiliary brake cylinder 4, and then allows the brake oil to enter the front axle brake 7 and the rear axle brake 8 of the vehicle through the shuttle valve 5 to achieve the braking of the equipment.

[0031] Embodiment 2 Control method of safety brake system for bulk cargo loader

[0032] like Figure 2 As shown, a control method for a safety brake system for a bulk cargo loader is provided, wherein the auxiliary safety device switch is turned on to start the auxiliary safety device, the distance signal between the bulk cargo loader and the aircraft is collected by the cooperation of the first distance signal collection device and the second distance signal collection device, the vehicle speed signal of the bulk cargo loader is collected by the vehicle speed sensor, and the collected distance signal and vehicle speed signal are transmitted to the controller, the controller processes and calculates the received distance signal and vehicle speed signal, and then outputs the processed and calculated signal to the proportional pressure reducing valve, controls the opening of the proportional pressure reducing valve to adjust the size of the brake pressure of the auxiliary brake cylinder, thereby controlling the size of the driving force of the bulk cargo loader, and realizing automatic deceleration and automatic braking of the bulk cargo loader.

[0033] In this embodiment, the control method specifically includes the following control modes:

[0034] (1) Automatic braking deceleration control in medium speed mode

[0035] The area within 3-9m from the aircraft is set as the medium-speed mode area. The maximum speed of the bulk cargo loader in the medium-speed mode area is set to 6km / h. Before the bulk cargo loader enters the medium-speed mode area, the auxiliary safety switch is turned on and the auxiliary safety device is in the starting state. When it is detected that the bulk cargo loader enters the medium-speed mode area, if the actual speed V of the bulk cargo loader is greater than 6km / h, according to the "medium-speed mode automatic brake deceleration control" formula in the controller, the controller outputs a proportional pressure reducing valve control current signal to the proportional pressure reducing valve, the auxiliary brake pump in the auxiliary brake cylinder is actuated, and the bulk cargo loader automatically decelerates. Before the actual distance between the bulk cargo loader and the aircraft is 3 meters, the actual speed of the bulk cargo loader drops below 6km / h, and then the system enters the medium-speed mode automatic brake deceleration control stage;

[0036] Among them, the formula for "mid-speed mode automatic braking deceleration control" is:

[0037] I1=(V-6) / (VH-6)*(braking force M2-braking force M1),

[0038] Wherein: I1 is the control current of the proportional pressure reducing valve in the medium speed mode; VH is the maximum vehicle speed that the bulk cargo loader can reach, which is 25 km / h in this embodiment; the braking force M1 is the braking force setting value 1 in the medium speed mode, the braking force M2 is the braking force setting value 2 in the medium speed mode, and the braking force M2> the braking force M1;

[0039] (2) Automatic braking and deceleration control in low speed mode

[0040] The area within 150mm to 3m from the aircraft is set as the low-speed mode area. The maximum driving speed of the bulk cargo loader in the medium-speed mode is limited to 0.8km / h. After the bulk cargo loader enters the low-speed mode area, if the actual speed V of the bulk cargo loader is greater than 0.8km / h, according to the "low-speed mode automatic brake deceleration control" formula in the controller, the controller outputs a proportional pressure reducing valve control current signal to the proportional pressure reducing valve, the auxiliary brake pump in the auxiliary brake cylinder is activated, and the bulk cargo loader automatically decelerates. Before the actual distance L between the bulk cargo loader and the aircraft is 150mm, the actual speed of the bulk cargo loader drops to V<0.8km / h, and the speed is maintained at 0.8km / h to continue driving, and then the system enters the automatic brake control stage;

[0041] Among them, the formula for "automatic braking deceleration control in low-speed mode" is:

[0042] I2=(V-0.8) / (6-0.8)*(braking force L2-braking force L1),

[0043] Wherein: I2 is the control current of the proportional pressure reducing valve in low speed mode, the braking force L1 is the braking force setting value 1 in low speed mode, the braking force L2 is the braking force setting value 2 in low speed mode, and the braking force H2>the braking force H1.

[0044] (3) Automatic brake control

[0045] When the actual distance between the bulk cargo loader and the aircraft is L = 150mm, the automatic brake control stage is immediately entered, and the controller outputs the maximum proportional pressure reducing valve control current signal to the proportional pressure reducing valve: I3 = 1000. The braking force of the auxiliary brake pump in the auxiliary brake cylinder is the maximum power, and the vehicle brakes automatically.

[0046] The above-mentioned specific implementations are only specific cases of the present invention. The patent protection scope of the present invention includes but is not limited to the product form and style of the above-mentioned specific implementations. Any appropriate changes or modifications made to them by ordinary technicians in the technical field that conform to the claims of the present invention shall fall within the patent protection scope of the present invention.

Claims

1. A control method for a safety brake system for a bulk cargo loader, characterized in that: It includes an auxiliary safety device, a proportional pressure reducing valve, a hydraulic power system, an auxiliary brake cylinder, a shuttle valve, a foot brake pump, a front axle brake of an automobile and a rear axle brake of an automobile. The auxiliary safety device includes an auxiliary safety device switch, a first distance signal acquisition device, a second distance signal acquisition device, a vehicle speed sensor and a controller. The auxiliary safety device switch, the first distance signal acquisition device, the second distance signal acquisition device and the vehicle speed sensor are all electrically connected to the controller. The controller is electrically connected to the proportional pressure reducing valve. The hydraulic oil inlet end of the proportional pressure reducing valve is connected to the hydraulic power system. The hydraulic oil outlet end of the proportional pressure reducing valve is connected to the auxiliary brake cylinder. The auxiliary brake cylinder is connected to the first oil inlet of the shuttle valve. The second oil inlet of the shuttle valve is connected to the foot brake pump. The oil outlet of the shuttle valve is connected to the front axle brake of the automobile and the rear axle brake of the automobile. The foot brake pump is also connected to the front axle brake of the automobile and the rear axle brake of the automobile. The auxiliary brake cylinder includes a hydraulic cylinder and an auxiliary brake pump connected to the hydraulic cylinder. The hydraulic oil outlet end of the proportional pressure reducing valve is connected to the hydraulic cylinder. The auxiliary brake pump is connected to the first oil inlet of the shuttle valve. The control method of the safety brake system for the bulk cargo loader is as follows: turn on the auxiliary safety device switch to start the auxiliary safety device, collect the distance signal between the bulk cargo loader and the aircraft through the cooperation of the first distance signal acquisition device and the second distance signal acquisition device, collect the vehicle speed signal of the bulk cargo loader through the vehicle speed sensor, and transmit the collected distance signal and vehicle speed signal to the controller, the controller processes and calculates the received distance signal and vehicle speed signal, and then outputs the processed and calculated signals to the proportional pressure reducing valve, controls the opening of the proportional pressure reducing valve to adjust the size of the brake pressure of the auxiliary brake cylinder, thereby controlling the size of the bulk cargo loader's driving force, and realizing automatic deceleration and automatic braking of the bulk cargo loader. The control method specifically includes the following control modes: (1) Automatic braking deceleration control in medium speed mode: The area within the distance L1 to L2 from the aircraft is set as the medium-speed mode area, L1>L2, and the maximum speed of the bulk cargo loader in the medium-speed mode area is set to V1. Before the bulk cargo loader enters the medium-speed mode area, the auxiliary safety switch is turned on, and the auxiliary safety device is in the starting state. When it is detected that the bulk cargo loader enters the medium-speed mode area, if the actual speed of the bulk cargo loader V>V1, according to the "medium-speed mode automatic brake deceleration control" formula I1=(V-V1) / (VH-V1)*(braking force M2-braking force M1) in the controller, where the braking force M2>braking force M1, the controller outputs a proportional pressure reducing valve control current signal to the proportional pressure reducing valve, and the auxiliary brake pump in the auxiliary brake cylinder is activated, and the bulk cargo loader automatically decelerates. Before the actual distance L between the bulk cargo loader and the aircraft is L=L2, the actual speed of the bulk cargo loader drops to V<V1, and then the system enters the low-speed mode automatic brake deceleration control stage; (2) Automatic braking deceleration control in low speed mode: The area within the distance from L2 to L3 to the aircraft is set as the low-speed mode area, L2>L3. The maximum driving speed of the bulk cargo loader in the low-speed mode is limited to V2. After the bulk cargo loader enters the low-speed mode area, if the actual speed V of the bulk cargo loader is greater than V2, according to the "low-speed mode automatic brake deceleration control" formula I2=(V-V2) / (V1-V2)*(braking force L2-braking force L1) in the controller, where the braking force L2>braking force L1, the controller outputs a proportional pressure reducing valve control current signal to the proportional pressure reducing valve, the auxiliary brake pump in the auxiliary brake cylinder is activated, and the bulk cargo loader automatically decelerates. Before the actual distance between the bulk cargo loader and the aircraft is L=L3, the actual speed of the bulk cargo loader drops to V<V2, and the speed V is maintained to continue driving, and then the system enters the automatic brake control stage; (3) Automatic brake control: When the actual distance between the bulk cargo loader and the aircraft is L=L3, the automatic brake control stage is immediately entered, the controller outputs the maximum proportional pressure reducing valve control current signal to the proportional pressure reducing valve, the braking force of the auxiliary brake pump in the auxiliary brake cylinder is the maximum braking force, and the vehicle brakes automatically.

2. The control method of the safety brake system for a bulk cargo loader according to claim 1, characterized in that: The first distance signal acquisition device is a radar sensor or a 3D camera.

3. The control method of the safety brake system for a bulk cargo loader according to claim 1, characterized in that: The second distance signal acquisition device is an ultrasonic sensor.

4. The control method of the safety brake system for a bulk cargo loader according to claim 1, characterized in that: The hydraulic oil of the hydraulic power system enters the hydraulic cylinder through the proportional pressure reducing valve, and drives the hydraulic cylinder to control the action of the auxiliary brake pump through the hydraulic oil. After the auxiliary brake pump is actuated, the brake oil enters the shuttle valve through the first oil inlet, and enters the front axle brake and the rear axle brake of the vehicle from the shuttle valve to control the deceleration and / or braking of the vehicle.

5. The control method of the safety brake system for a bulk cargo loader according to claim 1, 2, 3 or 4, characterized in that: The L1 is set to 9m, the L2 is set to 3m, and the L3 is set to 150mm; the V1 is set to 6km / h, and the V2 is set to 0.8km / h.

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