Brake interlock for fuel self-unloading vehicle

Abstract

The utility model provides a kind of fuel self-unloading vehicle brake interlocking device, it is related to the safety control technical field of self-unloading vehicle, and it is used in cooperation with fuel self-unloading vehicle, including carriage hoisting hydraulic device, air pressure parking brake device, travel switch, safety device and time limit button switch, pressure switch is equipped in the pipeline of carriage hoisting hydraulic device, power takeoff solenoid valve is equipped in the circuit of air pressure parking brake device, the pressure switch is electrically connected with power takeoff solenoid valve, the travel switch is electrically connected with pressure switch, the time limit button switch is shunt in the both ends of travel switch, the power takeoff solenoid valve is electrically connected with travel switch, when carriage hoisting, vehicle cannot travel, avoid the scratch and bump accident after carriage hoisting to occur;When needing vehicle to move temporarily, driver can operate time limit button switch, so that vehicle can move within 10~15 seconds, meet the demand of temporary movement, improve the security and convenience of operation.

Description

Technical Field

[0001] This utility model relates to the field of safety control technology for dump trucks, specifically a braking interlock device for a fuel-powered dump truck, used to interlock and control the vehicle's braking while the truck bed is raised, preventing the vehicle from moving. Background Technology

[0002] Currently, during the use of fuel-powered dump trucks, the frequent lifting of the truck bed makes it easy to scrape against height restrictions when unloading materials, causing serious damage to the vehicle and its contents, and severely delaying vehicle operation. Existing dump trucks can still drive with the truck bed raised, which leads to vehicle movement during this process, increasing the risk of scraping and collisions, and posing safety hazards. Especially when the truck bed is not fully lowered, driving the vehicle greatly increases the risk of accidents, seriously affecting the normal operation and safety of the vehicle.

[0003] In the existing technology, there is a lack of an effective interlocking safety device that can automatically force the vehicle to remain in a braking state when the carriage is lifted, and can temporarily and briefly release the brake when the vehicle position needs to be finely adjusted.

[0004] Therefore, there is an urgent need to develop a braking interlock device for fuel dump trucks. Utility Model Content

[0005] This utility model relates to a braking interlock device for fuel dump trucks. When the vehicle body is detected to be in a raised state, the device automatically and forcibly applies the parking brake, preventing the vehicle from moving. This fundamentally eliminates collision accidents caused by misoperation during vehicle body lifting and driving. At the same time, the device also has a time-limited unlocking function that allows the vehicle to make short-distance adjustments while in a raised state, taking into account both operational flexibility and safety, and effectively solving the aforementioned technical problems.

[0006] To achieve the above objectives, this utility model is implemented through the following technical solution: a braking interlock device for a fuel dump truck, used in conjunction with a fuel dump truck, including a cargo box lifting hydraulic device, a pneumatic parking brake device, a limit switch, a safety device, and a time-limiting button switch. The pipeline of the cargo box lifting hydraulic device is equipped with a pressure switch, the circuit of the pneumatic parking brake device is equipped with a power take-off solenoid valve, the pressure switch is electrically connected to the power take-off solenoid valve, the limit switch is electrically connected to the pressure switch, the time-limiting button switch is connected in parallel across the two ends of the limit switch, and the power take-off solenoid valve is electrically connected to the limit switch.

[0007] When the cargo box is lifted, the pressure switch detects the change in hydraulic pressure in the hydraulic line, controls the solenoid valve of the power take-off unit to be energized, and puts the pneumatic parking brake device in a braking state, so that the vehicle cannot move.

[0008] When the vehicle needs to be moved briefly, the driver operates the time-limited button switch in the cab to control the power take-off solenoid valve to be de-energized within the delay time, so that the air pressure parking brake is temporarily released and the vehicle can be moved. After the delay ends, the braking state is restored.

[0009] Preferably, the hydraulic lifting device for the cargo compartment includes a hydraulic oil tank, a lifting oil pump, a one-way valve, a lifting cylinder, and a limit valve, and the components of the hydraulic lifting device for the cargo compartment are connected by pipelines.

[0010] Preferably, the pneumatic parking brake device includes an air reservoir, a manual brake valve, a relay valve, and a brake caliper, and the components of the pneumatic parking brake device are connected by pipelines.

[0011] Preferably, the limit switch is installed on the dump truck frame. The limit switch is pressed into the open state when the truck bed is lowered. The limit switch is triggered to form a circuit when the truck bed is raised. A fuse is provided between the limit switch and the vehicle power supply. The limit switch is also electrically connected to the main power line of the fuse.

[0012] Preferably, when the power take-off solenoid valve is energized, it cuts off the control air source, causing the brake cylinder to vent, and the parking brake is locked; when the power take-off solenoid valve is de-energized, it connects the control air source and releases the brake.

[0013] Preferably, the delay time of the time-limited button switch is 10 to 15 seconds.

[0014] Beneficial effects

[0015] This utility model provides a braking interlock device for fuel dump trucks, which has the following advantages compared with the existing technology:

[0016] This invention achieves a rigid interlock between the lifting state of the cargo box and the driving state of the vehicle through the linkage of mechanical, hydraulic, electrical, and pneumatic systems, fundamentally avoiding lifting-driving accidents caused by misoperation and significantly improving safety. A time-limited movement function is also included, allowing the vehicle to be safely moved when short-distance adjustments are needed, such as during unloading, by pressing a time-limited button in the driver's cab. This caters to practical operational needs and is highly practical.

[0017] This invention features a simple structure, primarily utilizing existing vehicle systems for modification and retrofitting. The modification cost is low, reliability is high, and it is easy to promote and apply. Dual signal detection via limit switches and pressure switches ensures accurate status judgment and prevents malfunctions.

[0018] When the dump truck bed is raised, the vehicle cannot move forward, thus preventing accidents caused by the bed being raised. The vehicle cannot move while the bed is raised, preventing collisions. When a brief movement of the vehicle is required, the driver can operate the timed button switch to allow the vehicle to move within 10-15 seconds, meeting the needs of short-term movement and improving operational safety and convenience. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0020] Figure 1 This is a schematic diagram of the circuit connection of this utility model;

[0021] Figure 2 This is a schematic diagram showing the installation position of the device of this utility model;

[0022] In the picture:

[0023] 1. Hydraulic lifting device for the cargo box; 2. Pneumatic parking brake device; 3. Limit switch; 4. Time-limit button switch; 5. On-board power supply. Detailed Implementation

[0024] To make the technical problems, technical solutions and beneficial effects of this utility model clearer, this utility model will be further described in detail with reference to the embodiments and accompanying drawings. It should be understood that the specific embodiments described herein are only used to explain this utility model and are not intended to limit this utility model. The technical solutions of this utility model will be described in detail below with reference to the embodiments and accompanying drawings, but the scope of protection is not limited thereto.

[0025] Please see Figure 1 , 2 This utility model provides a technical solution:

[0026] A braking interlock device for a fuel dump truck, used in conjunction with the fuel dump truck, includes a cargo box lifting hydraulic device, a pneumatic parking brake device, a limit switch, a safety device, and a time-limiting button switch. The pipeline of the cargo box lifting hydraulic device is equipped with a pressure switch, the circuit of the pneumatic parking brake device is equipped with a power take-off solenoid valve, the pressure switch is electrically connected to the power take-off solenoid valve, the limit switch is electrically connected to the pressure switch, the time-limiting button switch is connected in parallel across the two ends of the limit switch, and the power take-off solenoid valve is electrically connected to the limit switch.

[0027] When the cargo box is lifted, the pressure switch detects the change in hydraulic pressure in the hydraulic line, and energizes the solenoid valve of the power take-off unit, which puts the pneumatic parking brake in the braking state and prevents the vehicle from moving.

[0028] When the vehicle needs to be moved briefly, the driver operates the time-limited button switch in the cab to control the power take-off solenoid valve to cut off the power within the delay time, so that the air pressure parking brake is temporarily released and the vehicle can be moved. After the delay ends, the braking state is restored.

[0029] In some embodiments, this device is added to the original system of the dump truck. The cargo box lifting hydraulic device 1 includes a hydraulic oil tank, a lifting oil pump, a one-way valve, a lifting cylinder, and a limit valve. The cargo box lifting hydraulic device 1 is connected via pipelines in the same way as the original fuel dump truck. The pneumatic parking brake device 2 includes an air reservoir, a manual brake valve, a relay valve, and a brake caliper. The pneumatic parking brake device 2 is connected via pipelines in the same way as the original fuel dump truck. A pressure switch is installed on the lifting hydraulic pipeline. A power take-off solenoid valve is installed in the circuit of the pneumatic parking brake device 2. The set pressure value of the pressure switch is slightly higher than the no-load standby pressure of the lifting system to ensure that it is triggered only when the lifting action occurs.

[0030] In some embodiments, a self-resetting time-limited button switch 4 is installed in an easily accessible location on the dashboard in the driver's cab. The delay time is adjustable and preferably set to 10-15 seconds.

[0031] In some embodiments, a normally open limit switch 3 is installed on the side of the vehicle subframe at a location where it can be pressed by the bottom pressure plate of the vehicle body when it is fully lowered. The installation of the limit switch 3 should ensure that it is only pressed in when the vehicle body is fully lowered (first state) and can quickly spring back to open (second state) as soon as the vehicle body is slightly raised.

[0032] In some embodiments, the pressure switch, limit switch 3, PTO solenoid valve, and time-limited push-button switch 4 are connected to the vehicle power supply 5 according to the following logic: the pressure switch is connected to one end of the PTO solenoid valve. The limit switch 3 is connected in series in the line between the vehicle power supply 5 and the PTO solenoid valve, and the time-limited push-button switch 4 is connected in parallel across the two ends of the limit switch 3. The other end of the PTO solenoid valve is connected to the time-limited push-button switch 4. In the entire circuit, a fuse is connected in series near the positive input terminal of the power supply.

[0033] In some embodiments, the power take-off solenoid valve is connected in series in the air circuit that controls the on / off state of the handbrake relay valve in the pneumatic parking brake device 2.

[0034] Working principle of this utility model:

[0035] When the vehicle is in the lowered position, limit switch 3 is pressed and is in the normally open state (first state). The lifting system has no pressure, the pressure switch is open, the power take-off solenoid valve is not energized, the parking brake is released, and the vehicle can drive normally.

[0036] When the truck bed is in the lifting state, the oil pressure in the lifting hydraulic line increases. After the pressure switch detects this pressure change, it closes the circuit. At the same time, the lifting of the truck bed triggers the limit switch 3 to close and send an electrical signal to the power take-off solenoid valve. After the power take-off solenoid valve is energized, the valve core moves down, controlling the parking brake switch circuit and cutting off the control air supply to the handbrake relay valve. The relay valve prevents high-pressure gas from reaching the brake cylinder, thereby causing the air pressure parking brake device 2 to be in a brake lock-up state, and the vehicle cannot move.

[0037] If the vehicle needs to be moved slightly while the cargo box is raised, the driver can press the timer switch 4. When pressed, the timer switch 4 closes, providing a parallel power supply path to the PTO solenoid valve. Even if the circuits of the pressure switch and limit switch 3 are in the conducting state, their normally closed contacts immediately open (cutting off the main power supply circuit), while the normally open contacts close, short-circuiting the PTO solenoid valve input terminal to the negative terminal of the power supply, forcing the PTO solenoid valve to de-energize and reset, temporarily releasing the pneumatic parking brake, and allowing the vehicle to move. After a preset delay time (10-15 seconds), the timer switch 4 automatically opens, the PTO solenoid valve is re-energized, and the brakes re-activate, preventing long-distance vehicle movement.

[0038] After unloading is completed, the truck bed is lowered and fully reset. The truck bed pressure limit switch 3 is then disconnected, cutting off the power take-off solenoid valve circuit. The power take-off solenoid valve is de-energized and resets, and the pneumatic parking brake device 2 resumes normal manual control function, allowing the vehicle to drive normally.

[0039] The above description is a further detailed explanation of the present invention in conjunction with specific preferred embodiments. For those skilled in the art to which the present invention pertains, several simple deductions or substitutions can be made without departing from the present invention, and all such deductions or substitutions should be considered as falling within the scope of patent protection determined by the submitted claims.

Claims

1. A braking interlock device for a fuel dump truck, used in conjunction with a fuel dump truck, characterized in that, The device includes a hydraulic lifting device for the cargo compartment, a pneumatic parking brake device, a limit switch, a safety device, and a time-limiting push button switch. The hydraulic lifting device for the cargo compartment is equipped with a pressure switch in its pipeline. The pneumatic parking brake device is equipped with a power take-off solenoid valve in its circuit. The pressure switch is electrically connected to the power take-off solenoid valve. The limit switch is electrically connected to the pressure switch. The time-limiting push button switch is connected in parallel across the two ends of the limit switch. The power take-off solenoid valve is electrically connected to the limit switch. When the cargo box is lifted, the pressure switch detects the change in hydraulic pressure in the hydraulic line, controls the solenoid valve of the power take-off unit to be energized, and puts the pneumatic parking brake device in a braking state, so that the vehicle cannot move. When the vehicle needs to be moved briefly, the driver operates the time-limited button switch in the cab to control the power take-off solenoid valve to be de-energized within the delay time, so that the air pressure parking brake is temporarily released and the vehicle can be moved. After the delay ends, the braking state is restored.

2. The braking interlock device according to claim 1, wherein the hydraulic lifting device for the cargo compartment includes a hydraulic oil tank, a lifting oil pump, a one-way valve, a lifting cylinder, and a limit valve, and the components of the hydraulic lifting device for the cargo compartment are connected by pipelines.

3. The braking interlock device according to claim 1, wherein the pneumatic parking brake device includes an air reservoir, a manual brake valve, a relay valve and a brake caliper, and the components of the pneumatic parking brake device are connected by pipelines.

4. The braking interlock device according to claim 1, wherein the limit switch is installed on the dump truck frame, the limit switch is pressed into an open state when the truck bed is lowered, the limit switch is triggered to restore the circuit when the truck bed is raised, a fuse is provided between the limit switch and the vehicle power supply, and the limit switch is electrically connected to the main power line of the fuse.

5. The braking interlocking device according to claim 1, characterized in that: When the power take-off solenoid valve is energized, it cuts off the control air source, causing the brake cylinder to vent air and the parking brake to be locked; when the power take-off solenoid valve is de-energized, the pneumatic parking brake is temporarily released.

6. The braking interlocking device according to claim 1, characterized in that: The delay time of the time-limited button switch is 10 to 15 seconds.

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