Large truck parking braking system

Abstract

The parking braking system comprises an air compressor used for generating high-pressure air, the air compressor communicates with a parking air storage cylinder, a front axle air storage cylinder and a rear axle air storage cylinder through a four-loop protection valve, and an air outlet of the parking air storage cylinder is connected with an air inlet of an air chamber at a parking braking hand valve. An air outlet of the air chamber is communicated with an air inlet of a normally open three-way electromagnetic valve, an air outlet of the three-way electromagnetic valve is connected with an air inlet of a parking relay valve, an exhaust port of the three-way electromagnetic valve is emptied, an air outlet of the parking relay valve is communicated with the brake air chamber, and the three-way electromagnetic valve, an emergency button, a fuse and a power supply form a series circuit loop. The normally-open three-way electromagnetic valve is installed between the parking air cylinder and the parking relay valve of an original automobile, the three-way electromagnetic valve can be controlled to be disconnected through the emergency button in an emergency situation, so that air supply into the brake air chamber is cut off, and then the spring in the brake air chamber can return to conduct braking.

Description

Technical Field

[0001] This application relates to a braking system, and more particularly to a parking brake system for large trucks. Background Technology

[0002] Air-pressure braking systems utilize compressed air as a power source and are commonly used in trucks and large trucks. They offer greater braking force than hydraulic braking systems, but their structure is more complex with numerous components. The working principle is as follows: an air pump generates compressed air, which is stored in an air reservoir. When braking is needed, the driver operates the brake pedal, opening the control valve of the master cylinder. This allows compressed air from the reservoir to enter the brake calipers, pushing them outwards and actuating the wheel brakes to generate braking force, slowing the vehicle to a stop. Modern cars generally use dual-circuit braking systems with independent control for the front and rear wheels. If one circuit loses braking function, the other circuit can continue to operate normally, preventing the vehicle from completely losing braking power.

[0003] To ensure greater vehicle safety and reliability, the service braking system and parking braking system, while sharing the same set of wheel brakes, have completely separate control systems. If one system fails, the other can still reliably bring the car to a stop. However, on seemingly flat but actually sloping terrain, drivers may forget to engage the handbrake due to human error. This causes the vehicle to slowly transition from a stationary state to a coasting state. This process can be rapid or slow, and by the time the driver notices the vehicle moving, it's often too late to get into the driver's seat and brake. Despite this, drivers may still attempt to brake to protect property, leading to frequent incidents of injury or death.

[0004] In existing technologies, although there are various structures for braking vehicles, such as setting up emergency braking structures inside the wheel brakes to ensure automatic braking even without engaging the handbrake, these structures are relatively complex and installed at the wheels. With prolonged exposure to vibrations, there is a certain probability of failure, requiring periodic disassembly and maintenance.

[0005] Therefore, in order to ensure that the driver can brake from outside the vehicle, it is necessary to design a parking brake system for large trucks that can be set outside the vehicle body to control the vehicle's braking and facilitate the driver's quick emergency braking. Summary of the Invention

[0006] The purpose of this application is to propose a parking brake system for large trucks that can control vehicle braking from outside the vehicle body, facilitating quick emergency braking by the driver.

[0007] This application is implemented as follows: A parking brake system for large trucks includes an air compressor for generating high-pressure air. The air compressor is connected to the parking air reservoir, the front axle air reservoir, and the rear axle air reservoir respectively through a four-circuit protection valve. The air outlet of the parking air reservoir is connected to the air inlet of the air chamber at the parking brake hand valve. The air outlet of the air chamber is connected to the air inlet of a normally open three-way solenoid valve. The air outlet of the three-way solenoid valve is connected to the air inlet of the parking relay valve. The exhaust port of the three-way solenoid valve is vented. The air outlet of the parking relay valve is connected to the brake air chamber. The three-way solenoid valve forms a series circuit with the emergency stop button, fuse, and power supply.

[0008] The three-way solenoid valve forms a series circuit with at least one set of emergency buttons and fuses.

[0009] The three-way solenoid valve, along with two sets of emergency buttons and fuses, forms two series circuits. The two sets of emergency buttons and fuses are connected in parallel and then connected in series with the power supply.

[0010] Two emergency buttons are located on the left and right sides of the vehicle, respectively.

[0011] After the air tanks of the front axle and rear axle are connected to the air chamber at the parking brake hand valve, they are then connected to the brake control master valve. The aforementioned parking relay valve is also connected to the brake control master valve.

[0012] The parking relay valve includes an air inlet, an air outlet, an exhaust port, and a control air port. The air inlet is connected to the parking air reservoir, the air outlet is connected to the brake air chamber, the exhaust port is connected to the exhaust port of the three-way solenoid valve, and the control air port is connected to the brake control master valve.

[0013] By implementing the above technical solution, this application only requires the installation of a normally open three-way solenoid valve between the existing vehicle's parking air reservoir and parking relay valve. In an emergency, the three-way solenoid valve can be disconnected via an emergency stop button, thereby cutting off the air supply to the brake chamber and allowing the spring in the brake chamber to return to its original position for braking. The three-way solenoid valve has the advantages of fast response and precise action, thus enabling rapid braking via the emergency stop button. This application is installed on the air pressure braking system of traditional vehicles, therefore it is applicable to various large, medium, and small freight vehicles. Attached Figure Description

[0014] The specific structure of this application is given by the following figures and embodiments:

[0015] Figure 1 This is a schematic diagram of the structure of this application;

[0016] Figure 2 This is a schematic diagram of a structure with emergency buttons on both sides. Detailed Implementation

[0017] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0018] In the description of this application, it should be understood that the terms "center", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0019] Example: Figure 1-2 As shown, the parking brake system of a large truck includes an air compressor for generating high-pressure air. The air compressor is connected to the parking air reservoir, the front axle air reservoir, and the rear axle air reservoir via a four-circuit protection valve. The outlet of the parking air reservoir is connected to the air inlet of the air chamber at the parking brake hand valve. The outlet of the air chamber is connected to the air inlet of a normally open three-way solenoid valve. The outlet of this three-way solenoid valve is connected to the air inlet of the parking relay valve. The exhaust port of the three-way solenoid valve is vented. The outlet of the parking relay valve is connected to the brake air chamber. The three-way solenoid valve forms a series circuit with the emergency stop button, fuse, and power supply. The air compressor, four-circuit protection valve, parking air reservoir, front axle air reservoir, rear axle air reservoir, parking brake hand valve, and parking relay valve are all existing technologies, and their structures and working principles are not the focus of this application and will not be described in detail here. The three-way solenoid valve is an Airtac 3V3 08 no B two-position three-way normally open solenoid valve with an operating voltage of 24V.

[0020] Furthermore, the brake chamber can be either a front axle brake chamber or a rear axle brake chamber. Both front and rear axle brake chambers are existing technologies. By controlling the air supply to the front or rear axle brake chamber, the spring inside the brake chamber can be returned to its original position for braking.

[0021] The three-way solenoid valve forms a series circuit with at least one set of emergency stop buttons and fuses. The emergency stop buttons allow the three-way solenoid valve to be opened and closed from outside the vehicle, thereby controlling the venting action in the brake chamber and achieving the purpose of venting the brake chamber in an emergency to apply the brakes.

[0022] Furthermore, the three-way solenoid valve, the two sets of emergency buttons, and the fuses form two series circuits, and the two sets of emergency buttons and fuses are connected in parallel and then connected in series with the power supply.

[0023] Furthermore, the two emergency buttons are located on the left and right sides of the vehicle body, preferably on either side of the driver's cab. By providing at least two emergency buttons on both sides of the vehicle, personnel can quickly approach and press them regardless of their location within the vehicle.

[0024] Furthermore, the front and rear axle air reservoirs are connected to the air chambers at the brake pedal, and then to the master brake control valve. The aforementioned parking relay valve is also connected to the master brake control valve. The parking relay valve is essentially an amplifying valve; it only controls a large volume of air with a small volume, without altering the vehicle's braking performance. In addition, due to the long wheelbase of trucks and the considerable distance between the master and wheel calipers, and the large air capacity of the rear axle wheel calipers, directly controlling the wheel calipers with the master cylinder would result in an excessively long braking response time and excessive braking distance. Therefore, a parking relay valve is installed closest to the rear wheel calipers. Air is supplied directly from the parking air reservoir through a thicker air pipe, and the opening and closing of the parking relay valve is controlled by a thinner air pipe on the master cylinder. This significantly shortens the braking response time, achieving a "fast charging, fast discharging" effect.

[0025] In this application, the parking relay valve includes an air inlet, an air outlet, an exhaust outlet, and a control air port. The air inlet is connected to the parking air reservoir, the air outlet is connected to the brake chamber, the exhaust outlet is connected to the exhaust port of the three-way solenoid valve, and the control air port is connected to the brake control master valve. When the brake pedal is depressed, the output air pressure at the parking brake hand valve serves as the control pressure input to the parking relay valve. Under the action of the control pressure, the air inlet valve at the parking relay valve is opened, allowing compressed air to enter the brake chamber directly from the parking air reservoir through the air inlet, without flowing through the parking brake valve. This significantly shortens the air filling pipeline of the brake chamber and accelerates the filling process. The specific structure of the parking relay valve is not the focus of this invention and will not be described in detail here.

[0026] When the car is in normal driving, the parking brake hand valve is in the on state. Compressed air in the parking air reservoir is supplied to the parking relay valve, causing the parking relay valve to open. Compressed air enters the brake chamber (power spring brake), compressing the power spring and releasing the parking brake. When the car stops, the parking brake hand valve is disconnected, cutting off the pipeline between the parking air reservoir and the parking relay valve. The parking relay valve closes, the compressed air is discharged, and the spring of the power spring parking brake returns to its original position, causing the wheel brakes to engage and thus bringing the car to a reliable stop.

[0027] When the parking brake hand valve is forgotten and emergency braking is needed, pressing the emergency stop button disconnects the three-way solenoid valve, cutting off the air supply between the parking air reservoir and the brake chamber. At this time, the air outlet and exhaust port are connected, the parking relay valve's inlet is closed, and the exhaust port is opened. Compressed air in the brake chamber is discharged through the exhaust port of the parking relay valve into the three-way solenoid valve. The high-powered spring brake on the brake chamber side activates, and the spring of the high-powered parking brake returns to its original position, engaging the wheel brakes and reliably stopping the vehicle.

[0028] The above technical features constitute the embodiments of this application, which have strong adaptability and implementation effect. Non-essential technical features can be added or removed according to actual needs to meet the needs of different situations.

Claims

1. A parking brake system for a large truck, comprising an air compressor for generating high-pressure air, the air compressor being connected to a parking air reservoir, a front axle air reservoir, and a rear axle air reservoir respectively via a four-circuit protection valve, the air outlet of the parking air reservoir being connected to the air inlet of the air chamber at the parking brake hand valve, characterized in that: The air outlet of the air chamber is connected to the air inlet of a normally open three-way solenoid valve. The air outlet of the three-way solenoid valve is connected to the air inlet of the parking relay valve. The exhaust port of the three-way solenoid valve is vented. The air outlet of the parking relay valve is connected to the brake air chamber. The three-way solenoid valve, emergency stop button, fuse and power supply form a series circuit.

2. The parking brake system for large trucks according to claim 1, characterized in that: The three-way solenoid valve forms a series circuit with at least one set of emergency buttons and fuses.

3. The parking brake system for large trucks according to claim 2, characterized in that: The three-way solenoid valve, along with two sets of emergency buttons and fuses, forms two series circuits. The two sets of emergency buttons and fuses are connected in parallel and then connected in series with the power supply.

4. The parking brake system for large trucks according to claim 3, characterized in that: Two emergency buttons are located on the left and right sides of the vehicle, respectively.

5. The parking brake system for large trucks according to claim 1, 2, or 3, characterized in that: After the air tanks of the front axle and rear axle are connected to the air chamber at the parking brake hand valve, they are then connected to the brake control master valve. The aforementioned parking relay valve is also connected to the brake control master valve.

6. The parking brake system for large trucks according to claim 5, characterized in that: The parking relay valve includes an air inlet, an air outlet, an exhaust port, and a control air port. The air inlet is connected to the parking air reservoir, the air outlet is connected to the brake air chamber, the exhaust port is connected to the exhaust port of the three-way solenoid valve, and the control air port is connected to the brake control master valve.

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