Hydraulic double-loop trailer control valve with preloading function and tractor

Abstract

The utility model relates to a hydraulic double-loop trailer control valve with a preloading function and a tractor. The control valve comprises a valve body, a three-position two-way valve and a control valve body are arranged in the valve body, a non-spring side cavity and a spring side cavity are formed in the two ends of a valve element of the three-position two-way valve respectively, the valve body is provided with a first air port communicated with the non-spring side cavity, the control valve body is provided with a first connector, a second connector and a third connector, and the valve body is provided with an air inlet connected with an inlet. An outlet of the three-position two-way valve is connected with the first connector, the valve body is provided with a control port connected with the third connector, a first pressing cavity and a second pressing cavity are formed in the two ends of a valve element of the control valve respectively, a first hydraulic cavity and a preloading cavity are formed in the first pressing cavity, and the valve body is provided with a brake oil port communicated with the first hydraulic cavity. The valve body is provided with an internal gas cut-off port communicated with the preloading cavity, the control port is communicated with the second pressure cavity, and the valve body is provided with a gas supply port communicated with the first connector. The double-loop trailer preloading device has the advantages that double-loop trailer preloading can be achieved, the consistency of a main brake and a hanging brake is ensured, and the brake safety performance is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of hydraulic valves, in particular to a hydraulic double-circuit trailer control valve with a preloading function and a tractor. Background Art

[0002] Most tractor trailer control systems utilize a single-loop system. This system is primarily used for low-horsepower tractors. Furthermore, because single-loop systems typically lack a preload system, they cannot achieve consistent braking between the main and trailer. This can result in a jerking or dragging sensation, resulting in a low safety factor and a poor driving experience. Furthermore, a single-loop system with an air circuit failure can affect the trailer's braking, further reducing its safety factor.

[0003] Based on this, it is necessary to develop a hydraulic dual-circuit trailer control valve and tractor with a preloading function. Utility Model Content

[0004] The technical problem to be solved by the utility model is to provide a hydraulic double-circuit trailer control valve with a preloading function and a tractor, which effectively overcomes the defects of the prior art.

[0005] The technical solution of the utility model to solve the above technical problems is as follows:

[0006] A hydraulic dual-circuit trailer control valve with a preload function, comprising a valve body, a three-position two-way valve and a control valve are arranged in the valve body, a non-spring side cavity and a spring side cavity with a spring are formed at both ends of the valve core movement direction of the three-position two-way valve, the valve body is provided with a first air port connected to the non-spring side cavity of the three-position two-way valve, the control valve is provided with a first interface, a second interface and a third interface, and when the valve core in the control valve moves, the third interface is selectively connected to the first interface or the second interface, the valve body is provided with a first air port connected to the three-position two-way valve The inlet of the valve is connected to the air inlet, the outlet of the above-mentioned three-position two-way valve is connected to the above-mentioned first interface, the above-mentioned valve body is provided with a control port connected to the above-mentioned third interface, and the two ends of the valve core movement direction of the above-mentioned control valve respectively form a first pressure chamber and a second pressure chamber, and the above-mentioned first pressure chamber is provided with a first hydraulic chamber and a preload chamber that are independent of each other, the above-mentioned valve body is provided with a brake oil port connected to the above-mentioned first hydraulic chamber, the above-mentioned valve body is provided with an internal air cut-off port connected to the above-mentioned preload chamber, the above-mentioned control port is connected to the above-mentioned second pressure chamber, and the above-mentioned valve body is provided with an air supply port connected to the above-mentioned first interface.

[0007] On the basis of the above technical solution, the present invention can also be improved as follows.

[0008] Furthermore, the first air port is connected and communicated with the internal air cut-off port through a flow channel.

[0009] Furthermore, a second hydraulic chamber and an air chamber independent of each other are provided in the second pressure chamber, the control port is communicated with the air chamber, and the valve body is provided with a hydraulic handbrake oil port communicated with the second hydraulic chamber.

[0010] Furthermore, two of the above-mentioned first hydraulic chambers are provided in parallel, and two of the above-mentioned brake oil ports are provided, which are respectively set as the left brake oil port and the right brake oil port. The above-mentioned left brake oil port and the right brake oil port are respectively connected to the two above-mentioned first hydraulic chambers in a one-to-one correspondence.

[0011] Furthermore, the spring side cavity of the three-position two-way valve is communicated with the air inlet of the valve body.

[0012] Furthermore, the third interface is communicated with the non-spring side cavity of the three-position two-way valve.

[0013] Furthermore, the valve body is provided with an exhaust port, and the exhaust port is communicated with the second interface.

[0014] Furthermore, the air supply port is connected to a pressure sensor.

[0015] Furthermore, the control port is connected to a pressure sensor.

[0016] The beneficial effects of the utility model are: simple and reasonable structural design, capable of realizing preloading of dual-circuit trailers, ensuring consistency of main and trailer brakes, and greatly improving brake safety performance.

[0017] A tractor is also provided that includes a hydraulic dual-circuit trailer control valve with a preload function. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 This is a structural schematic diagram of an embodiment of a hydraulic dual-circuit trailer control valve with a preloading function of the present utility model;

[0019] Figure 2 This is a structural schematic diagram of another embodiment of the hydraulic dual-circuit trailer control valve with a preloading function of the present utility model.

[0020] In the accompanying drawings, the components represented by the reference numerals are as follows:

[0021] 1. Three-position two-way valve; 2. Control valve; 21. Air supply port; 22. Control port. DETAILED DESCRIPTION

[0022] The principles and features of the present invention are described below in conjunction with the accompanying drawings. The examples given are only used to explain the present invention and are not used to limit the scope of the present invention.

[0023] Example 1

[0024] like Figure 1 and2 As shown, the hydraulic dual-circuit trailer control valve with preloading function of this embodiment includes a valve body, a three-position two-way valve 1 and a control valve 2 are arranged in the valve body, and the two ends of the valve core movement direction of the three-position two-way valve 1 respectively form a non-spring side cavity and a spring side cavity equipped with a spring, and the valve body is provided with a first air port a connected to the non-spring side cavity of the three-position two-way valve 1, and the control valve 2 is provided with a first interface b, a second interface c and a third interface d, and when the valve core in the control valve 2 moves, the third interface is selectively connected to the first interface or the second interface, and the valve body is provided with a first air port a connected to the non-spring side cavity of the three-position two-way valve 1, and the second interface is connected to the third interface. The inlet of the two-way valve 1 is connected to the air inlet e, the outlet f of the above-mentioned three-position two-way valve 1 is connected to the above-mentioned first interface, the above-mentioned valve body is provided with a control port 22 connected to the above-mentioned third interface, and the two ends of the valve core movement direction of the above-mentioned control valve 2 respectively form a first pressure chamber and a second pressure chamber, and the above-mentioned first pressure chamber is provided with a first hydraulic chamber and a preload chamber that are independent of each other, the above-mentioned valve body is provided with a brake oil port g connected to the above-mentioned first hydraulic chamber, the above-mentioned valve body is provided with an internal air cut-off port h connected to the above-mentioned preload chamber, the above-mentioned control port 22 is connected to the above-mentioned second pressure chamber, and the above-mentioned valve body is provided with an air supply port 21 connected to the above-mentioned first interface.

[0025] In the hydraulic dual-circuit trailer control valve with preload function of this embodiment, the brake oil port is connected to the oil circuit of the tractor's brake pedal, the air inlet of the valve body is connected to the internal air supply pipeline of the tractor, the internal air shut-off port is connected to the internal air supply pipeline of the tractor, the first air port is also connected to the internal air supply pipeline of the tractor, and the control port 22 and the air supply port 21 are respectively connected to the air circuit of the trailer. The specific working principle is as follows:

[0026] When driving, the spool of the three-position, two-way valve 1 is at the end away from the spring-side chamber (in this embodiment, it is assumed that the spool of the three-position, two-way valve 1 is in the left position), and the air inlet e is always connected to the air supply port 21. When the foot pedal is pressed, oil flows into the brake oil port g into the first hydraulic chamber, pushing the spool of the control valve 2 to move (to the right). Simultaneously, the internal air shut-off port h is connected, and air enters the preload chamber for preloading. At this time, the air path flows from the air inlet e to the control port 22. The control port 22 is connected to the air source, and the trailer brakes. Simultaneously, the air flow from the control port 22 is diverted to the second pressure chamber. Simultaneously, the air inlet of the first air port pushes the spool of the three-position, two-way valve 1 to move (to the right), reducing the amount of air entering the three-position, two-way valve 1. When the foot pedal is released, the air in the second pressure chamber pushes the spool of the control valve 2 to move (to the left) and reset, and exhaust is exhausted through the second port c. When parking, apply the parking brake, disconnecting brake oil port g. The air flow is from air inlet e to control port 22. Control port 22 is connected to the air source, and the trailer brakes are applied. The overall structural design is simple and rational, enabling dual-circuit trailer preloading, ensuring consistency between the main and trailer brakes, and significantly improving braking safety.

[0027] It should be noted that: since the hydraulic dual-circuit trailer control valve with preloading function in this embodiment is provided with a control port 22 and an air supply port 21, both of which supply air to the trailer, if any of these two ports fails, a signal can be fed back to the control system, thereby greatly improving the safety factor.

[0028] As a preferred embodiment, Figure 2 As shown, the first air port is connected to the internal shut-off port through a flow channel. The air source of the first air port comes from the internal shut-off port h, and the air is divided into the preload chamber and the non-spring side chamber of the three-position two-way valve 1, respectively, making the air path layout more concise.

[0029] As a preferred embodiment, the second pressure chamber is provided with a second hydraulic chamber and an air chamber which are independent of each other, the control port 22 is connected with the air chamber, and the valve body is provided with a hydraulic handbrake oil port m which is connected with the second hydraulic chamber.

[0030] In the above embodiment, when no braking is performed, the valve core of the control valve 2 is in the left position, the air supply port 21 supplies air normally, and the brake hydraulic oil of the parking brake will enter the second hydraulic chamber, acting on the valve core of the control valve 2 to force it to the left position, and the valve core always remains in the left position. When the brake pedal is stepped on, the valve core of the control valve 2 moves to the right position and overcomes the force of the brake hydraulic oil of the parking brake on the valve core. The air supply port 21 and the control port 22 are both connected. When the handbrake is pulled up, the hydraulic handbrake oil port m disconnects the oil supply.

[0031] In this embodiment, two first hydraulic chambers are provided in parallel, and two brake oil ports are provided, one for the left brake oil port and one for the right brake oil port. The left brake oil port and the right brake oil port are connected to the two first hydraulic chambers in a one-to-one correspondence. The two brake oil ports correspond to the left and right brake pedals, respectively, enabling flexible control.

[0032] In this embodiment, the spring-side chamber of the three-position, two-way valve 1 communicates with the air inlet of the valve body. The third port communicates with the non-spring-side chamber of the three-position, two-way valve 1. These two pressures maintain equilibrium when the air inlet e, the control port 22, remains open, ensuring that the valve core of the three-position, two-way valve 1 is in the left position.

[0033] In this embodiment, the valve body is provided with an exhaust port n, which is communicated with the second interface. When the valve core of the control valve 2 is in the left position, air is exhausted smoothly through the exhaust port.

[0034] In this embodiment, a pressure sensor is connected to the air supply port 21. The pressure sensor monitors the pressure information at the air supply port 21 in real time and feeds it back to the control system.

[0035] In this embodiment, a pressure sensor is connected to the control port 22. The pressure sensor monitors the pressure information at the control port 22 in real time and feeds back to the control system.

[0036] Example 2

[0037] The tractor of this embodiment includes the hydraulic dual-circuit trailer control valve with preload function in Embodiment 1.

[0038] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like to indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and 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, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation to the present invention.

[0039] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features being referred to. Thus, a feature specified as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of this utility model, "plurality" means at least two, such as two, three, etc., unless otherwise specifically defined.

[0040] In this utility model, unless otherwise specified or limited, the terms "installed," "connected," "connect," "fixed," etc. should be understood in a broad sense. For example, they can refer to fixed connection, detachable connection, or integration; mechanical connection, electrical connection; direct connection, or indirect connection through an intermediate medium; internal communication between two components, or interaction between two components, unless otherwise specified. Those skilled in the art will understand the specific meanings of the above terms in this utility model based on specific circumstances.

[0041] In the present invention, unless otherwise expressly specified or limited, when a first feature is "above" or "below" a second feature, it may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediary. Furthermore, when a first feature is "above," "above," or "above" a second feature, it may mean that the first feature is directly above or diagonally above the second feature, or simply means that the first feature is at a higher level than the second feature. When a first feature is "below," "below," or "below" a second feature, it may mean that the first feature is directly below or diagonally below the second feature, or simply means that the first feature is at a lower level than the second feature.

[0042] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art can combine and combine different embodiments or examples described in this specification and features of different embodiments or examples without contradiction.

[0043] Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are illustrative and cannot be understood as limitations on the present invention. Ordinary technicians in this field can change, modify, replace and modify the above embodiments within the scope of the present invention.

Claims

1. A hydraulic dual-circuit trailer control valve with preload function, characterized by: The invention comprises a valve body, wherein a three-position two-way valve (1) and a control valve (2) are arranged in the valve body, and a non-spring side cavity and a spring side cavity equipped with a spring are formed at both ends of the valve core moving direction of the three-position two-way valve (1), respectively. The valve body is provided with a first air port connected to the non-spring side cavity of the three-position two-way valve (1), and the control valve (2) is provided with a first interface, a second interface and a third interface. When the valve core in the control valve (2) moves, the third interface is selectively connected to the first interface or the second interface. The valve body is provided with an air inlet connected to the inlet of the three-position two-way valve (1). The outlet of the three-position two-way valve (1) is connected to the first interface, the valve body is provided with a control port (22) connected to the third interface, the two ends of the valve core movement direction of the control valve (2) respectively form a first pressure chamber and a second pressure chamber, the first pressure chamber is provided with a first hydraulic chamber and a preload chamber that are independent of each other, the valve body is provided with a brake oil port connected to the first hydraulic chamber, the valve body is provided with an internal air cut-off port connected to the preload chamber, the control port (22) is connected to the second pressure chamber, and the valve body is provided with an air supply port (21) connected to the first interface.

2. A hydraulic dual-circuit trailer control valve with preload function according to claim 1, characterized in that: The first gas port is connected and communicated with the internal gas cut-off port through a flow channel.

3. The hydraulic dual-circuit trailer control valve with preload function according to claim 1, characterized in that: A second hydraulic chamber and an air chamber that are independent of each other are provided in the second pressure chamber, the control port (22) is communicated with the air chamber, and the valve body is provided with a hydraulic handbrake oil port that is communicated with the second hydraulic chamber.

4. The hydraulic dual-circuit trailer control valve with preload function according to claim 1, characterized in that: There are two first hydraulic chambers arranged in parallel, and there are two brake oil ports, which are respectively a left brake oil port and a right brake oil port. The left brake oil port and the right brake oil port are respectively connected to the two first hydraulic chambers in a one-to-one correspondence.

5. The hydraulic dual-circuit trailer control valve with preload function according to claim 1, characterized in that: The spring side cavity of the three-position two-way valve (1) is communicated with the air inlet of the valve body.

6. The hydraulic dual-circuit trailer control valve with preload function according to claim 5, characterized in that: The third interface is in communication with the non-spring side cavity of the three-position two-way valve (1).

7. The hydraulic dual-circuit trailer control valve with preload function according to claim 1, characterized in that: The valve body is provided with an exhaust port, and the exhaust port is communicated with the second interface.

8. The hydraulic dual-circuit trailer control valve with preload function according to claim 1, characterized in that: The air supply port (21) is connected to a pressure sensor.

9. A hydraulic dual-circuit trailer control valve with a preload function according to any one of claims 1 to 8, characterized in that: The control port (22) is connected to a pressure sensor.

10. A tractor, characterized in that: The invention comprises a hydraulic dual-circuit trailer control valve with a preloading function as claimed in any one of claims 1 to 9.

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