Pre-braking system

Abstract

The utility model relates to the field of vehicle braking, and discloses a pre-braking system which comprises an air source device, a pre-braking device and a pre-braking device. The mixing control valve is connected with the air source device and used for being connected with the main vehicle oil brake system and the trailer air brake system, and the mixing control valve can be triggered when the main vehicle oil brake system supplies oil so as to drive the trailer air brake system to execute the braking action; the pre-brake control valve is connected between the air source device and the mixing control valve in a normally closed state and can be opened when being triggered, and the pre-brake control valve can introduce air of the air source device into the mixing control valve when being opened so as to trigger the mixing control valve to drive the trailer air brake system to execute the braking action; and the brake control mechanism is connected with the pre-brake control valve and is used for triggering the pre-brake control valve and the mixed control valve to act cooperatively when being controlled, so that the trailer air brake system and the main vehicle oil brake system can execute the brake action in sequence, the trailer can be prevented from impacting the main vehicle during braking, and the brake safety is effectively improved.

Description

Technical Field

[0001] This application belongs to the technical field of vehicle braking, and particularly relates to a pre-braking system. Background Art

[0002] For traditional vehicles (such as tractors) that are towed by a prime mover, their trailers generally use air brake systems to achieve the braking function. When braking, generally, a rod or wire is used to mechanically operate the air brake valve to drive the trailer air brake system. This trailer braking method has poor compatibility and consistency with the prime mover's hydraulic brake system. When the vehicle speed is relatively high, the trailer will have a large inertia due to its large weight (especially when carrying goods), and it is prone to the phenomenon of not being able to brake synchronously with the prime mover and impacting the prime mover, resulting in the inability to guarantee safety during braking. Utility Model Content

[0003] The purpose of this application is to provide a pre-braking system that can enable the prime mover's hydraulic brake system and the trailer's air brake system to operate in coordination, avoid the trailer impacting the prime mover during braking, and thus improve braking safety.

[0004] To achieve the above purpose, this application provides a pre-braking system, which includes:

[0005] An air source device;

[0006] A mixing control valve, connected to the air source device and used to connect the prime mover's hydraulic brake system and the trailer's air brake system. The mixing control valve can be triggered when supplied with oil by the prime mover's hydraulic brake system to drive the trailer's air brake system to perform a braking action;

[0007] A pre-brake control valve, connected between the air source device and the mixing control valve in a normally closed state and can be opened when triggered. The pre-brake control valve can introduce the gas from the air source device into the mixing control valve when opened to trigger the mixing control valve to drive the trailer's air brake system to perform a braking action; and

[0008] A brake operating mechanism, connected to the pre-brake control valve and used to trigger the pre-brake control valve and the mixing control valve to act in coordination when operated, so that the trailer's air brake system and the prime mover's hydraulic brake system can perform braking actions successively.

[0009] In some embodiments, the mixing control valve includes a valve housing, a valve core mechanism disposed in the housing cavity of the valve housing, and a main air inlet end, a main air exhaust end, an air inlet control end, an oil inlet control end, an air outlet energy supply end, and an air outlet control end disposed on the housing wall of the valve housing and respectively communicating with the housing cavity;

[0010] The air outlet energy supply end and the air outlet control end are both used to connect to the trailer air brake system. The main air inlet end is connected to the air source device. The air inlet control end is connected to the air source device through the pre-brake control valve. The oil inlet control end is used to connect to the main vehicle hydraulic brake system. The air inlet control end and the oil inlet control end can both be triggered when an input pressure is applied to control the valve core mechanism to move from the first valve core position to the second valve core position;

[0011] In the first valve core position, the air outlet control end is in communication with the main exhaust end, and the main air inlet end is cut off from communication with the air outlet control end; in the second valve core position, the air outlet control end is cut off from communication with the main exhaust end, and the main air inlet end is in communication with both the air outlet energy supply end and the air outlet control end.

[0012] In some embodiments, the pre-braking system further includes a pressure limiting valve, and the pre-brake control valve is connected to the air inlet control end through the pressure limiting valve; and / or, the pre-braking system further includes a gas storage device, and the air source device is connected to the pre-brake control valve and the main air inlet end through the gas storage device.

[0013] In some embodiments, the oil inlet control end includes a first oil inlet control end and a second oil inlet control end respectively used to connect to the left hydraulic brake system and the right hydraulic brake system in the main vehicle hydraulic brake system. The brake operating mechanism includes a left brake operating mechanism and a right brake operating mechanism. The left brake operating mechanism can trigger the opening of the pre-brake control valve when being operated and drive the left hydraulic brake system to operate so that the air inlet control end and the first oil inlet control end are sequentially triggered. The right brake operating mechanism can trigger the opening of the pre-brake control valve when being operated and drive the right hydraulic brake system to operate so that the air inlet control end and the second oil inlet control end are sequentially triggered.

[0014] In some embodiments, the pre-braking system further includes a drying device. The drying device includes a drying air inlet, a drying air outlet, a heater and a temperature sensor. The drying air inlet is connected to the air source device. The drying air outlet is connected to the pre-brake control valve and the mixing control valve. The temperature sensor is used to monitor the internal temperature of the drying device. The heater is set to be turned on when the internal temperature is less than a preset critical temperature and turned off when the internal temperature is not less than the preset critical temperature.

[0015] In some embodiments, the pre-braking system further includes a drying device and a regenerative gas storage device. The drying device includes a drying air inlet, a drying air outlet and a regenerative air outlet. The drying air inlet is connected to the air source device. The drying air outlet is connected to the pre-brake control valve and the mixing control valve. The regenerative gas storage device is connected to the regenerative air outlet and can blow gas back to the drying device.

[0016] In some embodiments, the pre-braking system further includes a drying device and a silencing device. The drying device includes a drying air inlet, a drying air outlet, and a relief valve. The relief valve is connected between the drying air inlet and the drying air outlet. The silencing device is connected to the outlet end of the relief valve.

[0017] In some embodiments, the pre-braking system further includes:

[0018] A parking control valve, which is used to be connected between the transmission hydraulic system and the hybrid control valve in a normally closed state and can be opened when triggered to conduct the transmission hydraulic system and the hybrid control valve;

[0019] A parking operating mechanism, which is used to stop triggering the parking control valve when operated to cut off the conduction between the transmission hydraulic system and the hybrid control valve. The hybrid control valve can be triggered to control both the trailer air brake system and the tractor oil brake system to perform braking actions when the parking control valve switches from the open state to the closed state.

[0020] In some embodiments, the pre-braking system further includes a first pressure sensor for monitoring the air pressure at the air supply end of the outlet and a second pressure sensor for monitoring the air pressure at the air control end of the outlet.

[0021] In some embodiments, the hybrid control valve further includes a throttling element disposed between the main air inlet end and the air supply end of the outlet; in a state where the spool mechanism is in the second spool position and the second pressure sensor monitors that the air pressure at the air control end of the outlet is less than a preset control air pressure, the main air inlet end communicates with the air supply end of the outlet through the throttling element; in a state where the spool mechanism is in the second spool position and the second pressure sensor monitors that the air pressure at the air control end of the outlet is not less than the preset control air pressure, the main air inlet end is directly connected to the air supply end of the outlet.

[0022] By adopting the pre-braking system of the present application, when braking is required, the pre-brake control valve can be first triggered to open by operating the brake operating mechanism, and the oil pump of the tractor oil brake system will also operate as the braking action progresses. In this way, the pre-brake control valve can introduce the gas from the gas source device into the hybrid control valve, and at the same time, the tractor oil brake system supplies oil to the hybrid control valve. On this basis, the hybrid control valve can preferentially output pre-brake control energy when the pre-brake control valve is first triggered and a relatively small air pressure is input, so as to drive the trailer air brake system to perform the braking action first. As the braking operation progresses, the tractor oil brake system will also perform the braking action after the trailer air brake system brakes. Therefore, as the action process of the braking operation progresses, the trailer air brake system will perform pre-emptively relative to the tractor oil brake system, thereby avoiding the trailer impacting the tractor during braking and effectively improving braking safety.

[0023] From the perspective of the entire braking process, the oil braking system of the tractor is linked to the air braking system of the trailer through a mixing control valve. The oil pressure of the tractor's oil braking system is proportional to the braking pressure of the trailer's air braking system, enabling the progressive output of this braking pressure, thereby achieving the coordinated operation of the tractor's oil braking system and the trailer's air braking system, and solving the problem of poor compatibility between the existing tractor's oil braking system and the trailer's air braking system.

[0024] Moreover, by adopting an integrated mixing control valve in this application, it is beneficial to reduce the number of valves in the system, thereby reducing potential failure points and effectively reducing the risk of brake failure. At the same time, this integrated mixing control valve also has the advantages of convenient installation, labor and time saving.

[0025] Other features and advantages of the embodiments of this application will be described in detail in the subsequent specific embodiment part. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The drawings are used to provide a further understanding of the embodiments of this application, and constitute a part of the specification. Together with the following specific embodiments, they are used to explain the embodiments of this application, but do not constitute a limitation to the embodiments of this application. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on the structures shown in these drawings. In the drawings:

[0027] Figure 1 is a schematic diagram of a pre-braking system in a specific embodiment of this application;

[0028] Figure 2 is Figure 1 a schematic diagram of the mixing control valve in

[0029] Figure 3 is a schematic structural diagram of a mixing control valve in a specific embodiment of this application.

[0030] DESCRIPTION OF THE REFERENCE NUMERALS

[0031] 1 Air source device 2 Drying device

[0032] 3 Regenerative air storage device 4 Sound silencing device

[0033] 5 Air storage device 6 Foot brake pedal

[0034] 7 Pre-brake control valve 8 Pressure limiting valve

[0035] 9 Mixing control valve 10 Handbrake lever

[0036] 11 Parking control valve 12 First air pressure sensor

[0037] 13 Second air pressure sensor

[0038] 91 Valve housing 92 Main air inlet end

[0039] 93 Main exhaust end 94 Air intake control end

[0040] 95 Oil inlet control end 96 Pressure relief control end

[0041] 97 Air outlet energy supply end 98 Air outlet control end

[0042] 99 First spring 910 Second spring

[0043] 911 Third spring 912 Pressure relief drive piston

[0044] 913 Core rod 914 Oil inlet drive piston

[0045] 915 Air intake drive piston 916 Differential piston

[0046] 917 Exhaust piston 918 Throttle element

[0047] 919 Exhaust clearance

[0048] 95a First oil inlet control end 95b Second oil inlet control end Detailed implementation manners

[0049] The following describes in detail the specific implementation manners of the present application with reference to the accompanying drawings. It should be understood that the specific implementation manners described herein are only for explaining and understanding the present application, and are not used to limit the present application.

[0050] Referring to Figures 1 to 3 , the first exemplary embodiment of the present application provides a pre-braking system, which includes an air supply unit and a brake control unit. The brake control unit is connected to the air supply unit, and the brake control unit is used to connect the trailer air brake system and the tractor oil brake system, and the brake control unit can also control the trailer air brake system and the tractor oil brake system to perform brake actions successively.

[0051] Through the above settings, during braking, the brake control unit can control the trailer air brake system and the tractor oil brake system to perform brake actions successively, so that the trailer with larger weight and inertia decelerates before the tractor, avoiding the trailer impacting the tractor during braking, thereby effectively improving the braking safety.

[0052] In some embodiments, the air supply unit includes an air source device 1. For example, the air source device 1 can be an air compressor, and the air compressor can supply compressed air to the brake control unit. The brake control unit includes a pre-brake control valve 7, a mixing control valve 9, and a brake operating mechanism.

[0053] Specifically, the hybrid control valve 9 is connected to the air source device 1, and the hybrid control valve 9 is used to connect the oil brake system of the tractor and the air brake system of the trailer. The hybrid control valve 9 can be triggered when supplied with oil by the oil brake system of the tractor to drive the air brake system of the trailer to perform a braking action.

[0054] The pre-brake control valve 7 is connected between the air source device 1 and the hybrid control valve 9 in a normally closed state, and the pre-brake control valve 7 can be opened when triggered. The pre-brake control valve 7 can introduce the gas of the air source device 1 into the hybrid control valve 9 when opened to trigger the hybrid control valve 9 to drive the air brake system of the trailer to perform a braking action.

[0055] The brake operating mechanism is connected to the pre-brake control valve 7, and the brake operating mechanism is used to first trigger the pre-brake control valve 7 when operated and cooperate with the hybrid control valve 9 to control the air brake system of the trailer and the oil brake system of the tractor to perform braking actions successively.

[0056] By adopting the setting of the embodiment, when braking is required, the pre-brake control valve 7 can be first triggered to open by operating the brake operating mechanism, and the oil pump of the oil brake system of the tractor will also operate as the braking action progresses. In this way, the pre-brake control valve 7 can introduce the gas of the air source device 1 into the hybrid control valve 9, and at the same time, the oil brake system of the tractor supplies oil to the hybrid control valve 9. On this basis, the hybrid control valve 9 can preferentially output pre-brake control energy when the pre-brake control valve 7 is first triggered and a relatively low air pressure is input, so as to drive the air brake system of the trailer to perform a braking action first. As the braking operation progresses, the oil brake system of the tractor will also perform a braking action after the air brake system of the trailer is braked. Therefore, as the action process of the braking operation progresses, the air brake system of the trailer will perform in advance relative to the oil brake system of the tractor, thus avoiding the trailer impacting the tractor during braking and effectively improving braking safety.

[0057] From the perspective of the entire braking process, the oil brake system of the tractor is linked with the air brake system of the trailer through the hybrid control valve 9. The oil pressure of the oil brake system of the tractor is in a proportional relationship with the braking pressure of the air brake system of the trailer, and the progressive output of the braking pressure can be realized, so as to realize the coordinated operation of the oil brake system of the tractor and the air brake system of the trailer and solve the problem of poor compatibility between the existing oil brake system of the tractor and the air brake system of the trailer.

[0058] Moreover, by adopting the integrated hybrid control valve 9 in this application, it is beneficial to reduce the number of valves in the system, thereby reducing potential failure points and effectively reducing the risk of brake failure. At the same time, the integrated hybrid control valve 9 also has the advantages of convenient installation, labor saving and time saving.

[0059] In some embodiments, the hybrid control valve 9 includes a valve housing 91, a valve core mechanism disposed in the housing cavity of the valve housing 91, and a main air inlet end 92, a main exhaust end 93, an air inlet control end 94, an oil inlet control end 95, an air outlet energy supply end 97, and an air outlet control end 98 that are disposed on the housing wall of the valve housing 91 and communicate with the housing cavity respectively.

[0060] Among them, both the air outlet energy supply end 97 and the air outlet control end 98 are used to connect to the trailer air brake system (usually the air outlet energy supply end 97 is connected to the air inlet end of the relay valve of the trailer air brake system, and the air outlet control end 98 is connected to the control end of the relay valve). The main air inlet end 92 is connected to the air source device 1, the air inlet control end 94 is connected to the air source device 1 through the pre-brake control valve 7, the oil inlet control end 95 is used to connect to the main vehicle oil brake system, and both the air inlet control end 94 and the oil inlet control end 95 can be triggered when an input pressure is applied to control the valve core mechanism to move from the first valve core position to the second valve core position.

[0061] When the valve core mechanism is in the first valve core position, the air outlet control end 98 is in communication with the main exhaust end 93, and the main air inlet end 92 is cut off from the air outlet control end 98. Therefore, the air outlet control end 98 cannot output gas to the trailer air brake system, and the trailer air brake system cannot be driven to operate. When the valve core mechanism is in the second valve core position, the air outlet control end 98 is cut off from the main exhaust end 93, and the main air inlet end 92 is in communication with both the air outlet energy supply end 97 and the air outlet control end 98. At this time, the trailer air brake system is driven to operate.

[0062] In addition, when the brake operating mechanism is manipulated by the user, it can move, thereby triggering the pre-brake control valve 7 to open and driving the oil pump of the main vehicle oil brake system to operate, so that the air inlet control end 94 and the oil inlet control end 95 are triggered in sequence.

[0063] Through the setting in this embodiment, when braking is required, the pre-brake control valve 7 can be triggered to open and the oil pump of the main vehicle oil brake system can be driven by manipulating the brake operating mechanism. Before the brake actuator of the main vehicle oil brake system obtains sufficient oil pressure to act and the oil inlet control end 95 of the hybrid control valve 9 is triggered by obtaining sufficient oil pressure from the main vehicle oil brake system, the air inlet control end 94 of the hybrid control valve 9 can be first triggered when a relatively small air pressure is input from the air source device 1 through the pre-brake control valve 7. Thus, before the main vehicle oil brake system executes the braking action, the air inlet control end 94 first controls the valve core mechanism of the hybrid control valve 9 to move from the first valve core position to the second valve core position, so that the main air inlet end 92 connecting the air source device 1 in the hybrid control valve 9 is in communication with the air outlet energy supply end 97 and the air outlet control end 98. In this way, the air outlet energy supply end 97 can supply air to the trailer air brake system, and the air outlet control end 98 can control the operation of the trailer air brake system, thereby driving the trailer air brake system to execute the braking action prior to the main vehicle oil brake system.

[0064] Subsequently, when the oil inlet control end 95 of the mixing control valve 9 is triggered, the oil inlet control end 95 can control the valve core mechanism, so that the main vehicle oil brake system is linked with the trailer air brake system through the mixing control valve 9. Thus, the oil pressure of the main vehicle oil brake system is in a proportional relationship with the braking pressure of the trailer air brake system, and the progressive output of the braking pressure can be realized.

[0065] In some embodiments, referring to Figure 3 , the oil inlet control end 95, the air inlet control end 94, the air outlet control end 98, the main air inlet end 92 and the main exhaust end 93 are arranged in sequence along the axial direction of the valve housing 91. The valve core mechanism includes a first spring 99, a second spring 910, an oil inlet driving piston 914, an air inlet driving piston 915, a differential piston 916 and an exhaust piston 917 provided with an exhaust passage.

[0066] Among them, the oil inlet driving piston 914, the air inlet driving piston 915, the differential piston 916 and the exhaust piston 917 are respectively aligned with the oil inlet control end 95, the air inlet control end 94, the air outlet control end 98 and the main air inlet end 92 along the radial direction of the valve housing 91. The first spring 99 and the second spring 910 are respectively used to drive the differential piston 916 and the exhaust piston 917 to reset. In addition, the air outlet energy supply end 97 is kept in communication with the main air inlet end 92.

[0067] When the valve core mechanism is in the first valve core position, neither the first spring 99 nor the second spring 910 is stressed, and the differential piston 916 and the exhaust piston 917 are axially spaced apart (an exhaust gap 919 is formed at the spaced part). At this time, the exhaust passage of the exhaust piston 917 conducts the air outlet control end 98 and the main exhaust end 93 (specifically, the air outlet control end 98, the exhaust gap 919, the exhaust passage of the exhaust piston 917 and the main exhaust end 93 are conducted in sequence). One end of the exhaust piston 917 facing the differential piston 916 abuts against the inner peripheral part of the valve housing 91 to cut off the conduction between the main air inlet end 92 and the air outlet control end 98. Therefore, at this time, the air outlet control end 98 cannot output gas to the trailer air brake system, and the trailer air brake system cannot be driven to operate.

[0068] When the pre-brake control valve 7 is opened to trigger the intake control end 94, air pressure is formed at the intake control end 94 to push the intake drive piston 915 and the differential piston 916 towards the exhaust piston 917 (during this process, the first spring 99 is compressed), until the differential piston 916 axially abuts against the exhaust piston 917, the communication between the air outlet control end 98 and the main exhaust end 93 can be cut off. Immediately afterwards, the air pressure at the intake control end 94 continues to push the intake drive piston 915, the differential piston 916 and the exhaust piston 917 towards the main exhaust end 93 (during this process, both the first spring 99 and the second spring 910 are compressed), so that the end of the exhaust piston 917 facing the differential piston 916 is disengaged from the inner peripheral part of the valve housing 91 to conduct the main intake end 92 and the air outlet control end 98 (that is, the valve core mechanism moves to the second valve core position). At this time, since the main intake end 92 is in communication with both the air outlet energy supply end 97 and the air outlet control end 98, the trailer air brake system is driven to operate. At the same time, the brake actuator of the tractor hydraulic brake system does not receive sufficient hydraulic pressure to act, and the oil inlet control end 95 is not triggered by receiving sufficient hydraulic pressure from the tractor hydraulic brake system. Therefore, the brake actuator of the trailer air brake system will act prior to the brake actuator of the tractor hydraulic brake system.

[0069] When the air pressure at the air outlet control end 98 is balanced with the air pressure at the intake control end 94, the compressed first spring 99 and second spring 910 can drive the intake drive piston 915, the differential piston 916 and the exhaust piston 917 to reset, thereby re-conducting the air outlet control end 98 and the main exhaust end 93, and re-cutting off the communication between the main intake end 92 and the air outlet control end 98.

[0070] But at the same time, the brake actuator of the main vehicle's oil brake system has obtained sufficient oil pressure to operate, and the oil inlet control end 95 has obtained sufficient oil pressure from the main vehicle's oil brake system and has been triggered. Therefore, the oil pressure at the oil inlet control end 95 can again push the intake drive piston 915 and the differential piston 916 to move toward the exhaust piston 917 (the first spring 99 is compressed during this process), until the differential piston 916 and the exhaust piston 917 are axially abutted, and the conduction between the outlet control end 98 and the main exhaust end 93 can be cut off again. Then, the oil pressure at the oil inlet control end 95 continues to push the intake drive piston 915, the differential piston 916 and the exhaust piston 917 to move toward the main exhaust end 93 (during this process, the first spring 99 and the second spring 910 are both compressed), so that the end of the exhaust piston 917 toward the differential piston 916 is out of contact with the inner periphery of the valve housing 91 to connect the main intake end 92 and the air outlet control end 98 again (that is, the valve core mechanism moves to the second valve core position). At this time, since the main intake end 92 is connected to the air outlet energy supply end 97 and the air outlet control end 98, the trailer air brake system continues to be driven and operated by the oil inlet control end 95. At this time, it is equivalent to the main vehicle oil brake system being linked with the trailer air brake system through the mixing control valve 9, and the oil pressure of the main vehicle oil brake system is used to continue to control the operation of the trailer air brake system. Not only that, the output oil pressure of the main vehicle oil brake system is proportional to the braking pressure of the trailer air brake system, so that the progressive output of the braking pressure can be achieved.

[0071] When the brake operating mechanism is reset, the pre-brake control valve 7 is closed and the oil pump of the main vehicle's oil brake system stops running, so that the air pressure at the intake control end 94 and the oil pressure at the oil intake control end 95 gradually decrease, and the valve core mechanism cannot continue to be maintained in the second valve core position. At this time, under the elastic force of the first spring 99 and the second spring 910, the valve core mechanism is reset to the first valve core position, and the exhaust channel of the exhaust piston 917 connects the air outlet control end 98 and the main exhaust end 93, and the main air intake end 92 and the air outlet control end 98 are cut off.

[0072] In some embodiments, the brake operating mechanism includes a foot brake plate 6 and a foot brake position sensor for detecting the position of the foot brake plate 6. The foot brake position sensor is electrically connected to the control end of the pre-brake control valve 7. The foot brake position sensor is usually arranged at the starting end of the pedal stroke of the foot brake plate 6 to first trigger the trailer air brake and then trigger the main vehicle oil brake. For example, the foot brake position sensor can use a travel switch. When the user steps on the foot brake plate 6, the foot brake plate 6 immediately triggers the travel switch. The travel switch sends a signal to the control end of the pre-brake control valve 7, thereby controlling the pre-brake control valve 7 to open. In addition, the pre-brake control valve 7 can use different types of control valves such as a normally closed two-position three-way solenoid valve.

[0073] In some embodiments, the pre-braking system further includes a pressure-limiting valve 8. At this time, the pre-brake control valve 7 is connected to the air intake control end 94 through the pressure-limiting valve 8. By setting the pressure-limiting valve 8, the air pressure range at the air intake control end 94 can be limited.

[0074] In some embodiments, the pre-braking system further includes an air storage device 5. At this time, the air source device 1 is connected to the pre-brake control valve 7 and the main air intake end 92 through the air storage device 5. The air storage device 5 can ensure sufficient gas output to the pre-brake control valve 7 and the main air intake end 92, which is beneficial to improving the stability and reliability of the system.

[0075] In some embodiments, referring to Figure 1 and Figure 3 , the brake operating mechanism includes a left brake operating mechanism and a right brake operating mechanism (such as the brake operating mechanism in a tractor). At this time, the oil inlet control end 95 may include a first oil inlet control end 95a and a second oil inlet control end 95b respectively used to connect the left oil brake system and the right oil brake system in the main vehicle oil brake system. Among them, the left brake operating mechanism can trigger the opening of the pre-brake control valve 7 when being operated and drive the left oil brake system to operate so that the air intake control end 94 and the first oil inlet control end 95a are triggered in sequence. The right brake operating mechanism can trigger the opening of the pre-brake control valve 7 when being operated and drive the right oil brake system to operate so that the air intake control end 94 and the second oil inlet control end 95b are triggered in sequence. Therefore, no matter whether the user operates the left brake operating mechanism or the right brake operating mechanism, the linkage control of the main vehicle oil brake system and the trailer air brake system can be realized.

[0076] In some embodiments, the pre-braking system further includes a parking control unit, which is used to control the brake control unit to drive the trailer air brake system to perform a braking action, and the parking control unit is also used to control the main vehicle oil brake system to perform a braking action.

[0077] Through the setting in this embodiment, during parking, the parking control unit can control both the main vehicle oil brake system and the trailer air brake system to perform braking actions, realizing the parking linkage control of the main vehicle and the trailer, thereby simplifying the user's parking operation.

[0078] In some embodiments, the parking control unit includes a parking control valve 11 and a parking operating mechanism. Specifically, the parking control valve 11 is used to connect the transmission hydraulic system and the hybrid control valve 9 in a normally closed state, and the parking control valve 11 can be triggered to open to conduct the transmission hydraulic system and the hybrid control valve 9. For example, in the state where the vehicle is started, when the parking operating mechanism is not operated, the parking control valve 11 will always be triggered and remain in the open state, thereby conducting the transmission hydraulic system and the hybrid control valve 9. The parking operating mechanism is used to stop triggering the parking control valve 11 to cut off the conduction between the transmission hydraulic system and the hybrid control valve 9 when it is operated (such as pulling the parking brake lever 10). The hybrid control valve 9 can be triggered to control both the trailer air brake system and the host vehicle oil brake system to perform braking actions when the parking control valve 11 switches from the open state to the closed state.

[0079] In some embodiments, the hybrid control valve 9 further includes a pressure relief control end 96 provided on the wall of the valve housing 91 and communicating with the housing cavity. The pressure relief control end 96 can be triggered during pressure relief to control the valve core mechanism to move from the first valve core position to the second valve core position. At this time, the parking control valve 11 is used to connect the transmission hydraulic system and the pressure relief control end 96. In addition, the parking operating mechanism is used to connect the host vehicle oil brake system and is used to stop triggering the parking control valve 11 to cut off the conduction between the transmission hydraulic system and the hybrid control valve 9 when it is operated (such as pulling the parking brake lever 10), so that the pressure relief control end 96 is triggered by pressure relief. At this time, the valve core mechanism is controlled by the pressure relief control end 96 to move from the first valve core position to the second valve core position, driving the trailer air brake system to perform braking actions. At the same time, the parking operating mechanism also drives the host vehicle oil brake system to perform braking actions, thereby realizing the parking linkage control of the host vehicle and the trailer.

[0080] In some embodiments, referring to Figure 3 , the pressure relief control end 96, the air outlet control end 98, the main air inlet end 92 and the main exhaust end 93 are arranged in sequence along the axial direction of the valve housing 91. The valve core mechanism includes a first spring 99, a second spring 910, a third spring 911 and a pressure relief driving piston 912, a core rod 913 (for example, the core rod 913 movably passes through the oil inlet driving piston 914 and the air inlet driving piston 915 in sequence), a differential piston 916 and an exhaust piston 917 (provided with an exhaust passage) arranged in sequence along the axial direction of the valve housing 91.

[0081] Among them, the pressure relief driving piston 912, the differential piston 916 and the exhaust piston 917 are respectively aligned with the pressure relief control end 96, the air outlet control end 98 and the main air inlet end 92 in the radial direction of the valve housing 91. The first spring 99, the second spring 910 and the third spring 911 are respectively used to drive the differential piston 916, the exhaust piston 917 and the pressure relief driving piston 912 to reset. The air outlet energy supply end 97 remains in communication with the main air inlet end 92.

[0082] When the spool mechanism is in the first spool position, neither the first spring 99 nor the second spring 910 is under force, and the parking control valve 11 is in the open state. Therefore, there is oil pressure at the pressure relief control end 96, and the pressure relief driving piston 912 compresses the third spring 911 under the action of the oil pressure at the pressure relief control end 96. In addition, the differential piston 916 and the exhaust piston 917 are axially spaced apart (an exhaust gap 919 is formed at the spaced part), and the exhaust passage conducts the air outlet control end 98 and the main exhaust end 93 (specifically, the air outlet control end 98, the exhaust gap 919, the exhaust passage of the exhaust piston 917, and the main exhaust end 93 are conducted in sequence). One end of the exhaust piston 917 facing the differential piston 916 abuts against the inner peripheral part of the valve housing 91 to cut off the conduction between the main air inlet end 92 and the air outlet control end 98. Therefore, at this time, the air outlet control end 98 cannot output gas to the trailer air brake system, and the trailer air brake system cannot be driven to operate.

[0083] When the user manipulates the parking operating mechanism (such as pulling the handbrake lever 10) to stop triggering the parking control valve 11, the parking control valve 11 switches from the open state to the closed state, and the transmission hydraulic system is cut off from the hybrid control valve 9. As a result, the pressure relief control end 96 is depressurized, and the pressure relief driving piston 912 pushes the core rod 913 and the differential piston 916 towards the exhaust piston 917 under the elastic force of the third spring 911 in the compressed state (the first spring 99 is compressed under force during this process). Until the differential piston 916 and the exhaust piston 917 are axially abutted, the conduction between the air outlet control end 98 and the main exhaust end 93 can be cut off. Immediately afterwards, the third spring 911 continues to push the pressure relief driving piston 912, the core rod 913, the differential piston 916, and the exhaust piston 917 towards the main exhaust end 93 (the first spring 99 and the second spring 910 are both compressed under force during this process), so that one end of the exhaust piston 917 facing the differential piston 916 is separated from the inner peripheral part of the valve housing 91 to conduct the main air inlet end 92 and the air outlet control end 98 (that is, the spool mechanism moves to the second spool position). At this time, since the main air inlet end 92 is conducted with both the air outlet energy supply end 97 and the air outlet control end 98, the trailer air brake system is driven to operate. At the same time, the parking operating mechanism drives the main vehicle oil brake system to operate, so as to realize the parking linkage control of the main vehicle and the trailer.

[0084] When the parking control mechanism is reset (for example, when the parking brake lever 10 is released), the parking control valve 11 is triggered again to switch from the closed state to the open state, so that the transmission hydraulic system supplies oil to the pressure relief control end 96 again. As a result, the pressure relief driving piston 912 compresses the third spring 911 under the oil pressure of the pressure relief control end 96. The differential piston 916 and the exhaust piston 917 lose the thrust from the third spring 911. Therefore, the differential piston 916 and the exhaust piston 917 will reset under the elastic force of the first spring 99 and the second spring 910 in the compressed state, and at the same time drive the core rod 913 to reset, so that the valve core mechanism resets to the first valve core position. The exhaust passage of the exhaust piston 917 re-conducts the air outlet control end 98 and the main exhaust end 93, and the main air inlet end 92 and the air outlet control end 98 are re-truncated and conducted.

[0085] In some embodiments, the parking control valve 11 can adopt different types of control valves such as normally closed two-position three-way solenoid valves.

[0086] In some embodiments, the pre-braking system further includes a gas drying unit, which is connected between the air supply unit and the brake control unit and can dry the gas output by the air supply unit. For example, the gas drying unit can be connected to the main air inlet end 92 and the pre-brake control valve 7, or connected to the main air inlet end 92 and the pre-brake control valve 7 through the gas storage device 5.

[0087] By using the gas drying unit to dry the gas output by the air supply unit, it is possible to prevent condensed water (such as the condensed water formed when the high-temperature gas discharged by the air compressor encounters cold) from flowing in the pre-braking system, avoid premature damage to various components in the pre-braking system and cause brake function failure, extend the service life of the components, and thus improve the driving safety factor.

[0088] In some embodiments, the gas drying unit includes a drying device 2, and the drying device 2 includes a drying air inlet, a drying air outlet, a heater, and a temperature sensor. Among them, the drying air inlet is connected to the air supply unit, the drying air outlet is connected to the brake control unit, the temperature sensor is used to monitor the internal temperature of the drying device 2, and the heater is set to be able to turn on when the internal temperature is less than the preset critical temperature and turn off when the internal temperature is not less than the preset critical temperature.

[0089] Through the above settings, the heater can reheat the condensed water into water vapor, making it easier for the desiccant in the drying device 2 to absorb. By determining the start and stop timing of the heater through the temperature sensor, the energy consumption of the heater can be saved and the cost can be reduced.

[0090] In some embodiments, the gas drying unit includes a drying device 2 and a regeneration gas storage device 3. The drying device 2 includes a drying air inlet, a drying air outlet, and a regeneration air outlet. Among them, the drying air inlet is connected to the air supply unit, the drying air outlet is connected to the brake control unit, and the regeneration gas storage device 3 is connected to the regeneration air outlet and can blow back gas to the drying device 2.

[0091] By blowing back gas from the regeneration gas storage device 3 to the drying device 2, the moisture in the desiccant can be blown into the atmosphere, thereby maintaining the activity of the desiccant for a long time and ensuring that the drying device 2 can work effectively for a long time.

[0092] In some embodiments, the gas drying unit includes a drying device 2 and a silencing device 4. The drying device 2 includes a drying air inlet, a drying air outlet, and a relief valve. Among them, the relief valve is connected between the drying air inlet and the drying air outlet, and the silencing device 4 is connected to the air outlet end of the relief valve.

[0093] When the air pressure in the air circuit exceeds the preset maximum value, the relief valve can relieve the pressure, so as to ensure that the air pressure in the air circuit is restored below the preset maximum value. When the relief valve continuously relieves the pressure, a large amount of noise will be generated. Therefore, a silencing device 4 is provided to reduce the noise and improve the human comfort and driving experience.

[0094] In some embodiments, the pre-braking system further includes a air pressure monitoring unit, which is connected to the brake control unit and can monitor the gas pressure output by the brake control unit to the trailer air brake system, and can monitor whether there is air leakage in the system in real time, which is convenient for fault judgment. For example, the air pressure monitoring unit can be connected to the display screen in the vehicle, so that the monitoring results of the air pressure monitoring unit can be displayed in real time on the display screen, which is convenient for users to know in time whether the current pre-braking system can operate normally. In addition, the air pressure monitoring unit can include a first air pressure sensor 12 for monitoring the air pressure of the air outlet energy supply end 97 and a second air pressure sensor 13 for monitoring the air pressure of the air outlet control end 98. Even further, a third air pressure sensor can be set to monitor the gas pressure of the gas storage device 5. Similarly, the third air pressure sensor can also be connected to the display screen in the vehicle.

[0095] In some embodiments, the mixing control valve 9 further includes a throttling element 918 disposed between the main air inlet end 92 and the air outlet energy supply end 97. In a state where the valve core mechanism is in the second valve core position and the second air pressure sensor 13 monitors that the air pressure of the air outlet control end 98 is less than the preset control air pressure, the main air inlet end 92 communicates with the air outlet energy supply end 97 through the throttling element 918. In a state where the valve core mechanism is in the second valve core position and the second air pressure sensor 13 monitors that the air pressure of the air outlet control end 98 is not less than the preset control air pressure, the main air inlet end 92 is directly connected to the air outlet energy supply end 97.

[0096] The above settings can be applicable to the case where the air outlet control end 98 leaks. Specifically, when the air outlet control end 98 leaks, if the user operates the brake operating mechanism (such as stepping on the foot brake pedal 6), the vehicle will determine that the current valve core mechanism is in the second valve core position and the second air pressure sensor 13 monitors that the air pressure at the air outlet control end 98 is less than the preset control air pressure. At this time, the throttle element 918 automatically opens and connects the main air inlet end 92 and the air outlet energy supply end 97, so that the amount of gas flowing from the main air inlet end 92 to the air outlet energy supply end 97 decreases sharply. At the same time, the gas in the air outlet energy supply end 97 quickly discharges to the atmosphere through the leakage point of the air outlet control end 98, resulting in a sharp drop in the air pressure in the air outlet energy supply end 97 (usually equivalent to the air pressure at the air inlet of the brake valve in the trailer air brake system), for example, dropping to 150 kPa within 2 seconds. In this way, the emergency braking function in the vehicle can be triggered to avoid the situation of vehicle slipping and ensure the safety during traveling braking or slope parking. When the brake or parking is released, the throttle element 918 can automatically close again, making the main air inlet end 92 directly connected to the air outlet energy supply end 97.

[0097] The second exemplary embodiment of the present application further provides a braking assembly, which includes a main vehicle oil brake system for being arranged on the main vehicle, a trailer air brake system for being arranged on the trailer towed by the main vehicle, and the above-mentioned pre-braking system connected between the main vehicle oil brake system and the trailer air brake system.

[0098] The third exemplary embodiment of the present application further provides a tractor, which includes a main vehicle, a trailer, and the above-mentioned braking assembly.

[0099] In the description of the present application, it should be understood that the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include at least one of such features. In the description of the present application, the meaning of "a plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0100] In the present application, unless otherwise clearly specified and defined, the terms "installed", "connected", "connected with", "fixed" and other terms should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or integrated; it can be a mechanical connection, an electrical connection or communication with each other; it can be directly connected, or indirectly connected through an intermediate medium, and can be the communication inside two elements or the interaction relationship between two elements, unless otherwise clearly defined. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to specific situations.

[0101] In the description of this specification, the descriptions referring to terms such as "one embodiment", "some embodiments", "examples", "specific examples", or "some examples", etc., mean that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of this application. 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 may be combined in any one or more embodiments or examples in a suitable manner. In addition, without contradiction, those skilled in the art can combine and combine the different embodiments or examples described in this specification and the features of different embodiments or examples.

[0102] Although the embodiments of this application have been shown and described above, it can be understood that the above embodiments are exemplary and should not be construed as limitations on this application. Those of ordinary skill in the art can make changes, modifications, substitutions, and variations to the above embodiments within the scope of this application.

Claims

1. A pre-braking system, characterized in that: include: Air source device (1); A mixing control valve (9) is connected to the air source device (1) and is used to connect the main vehicle oil brake system and the trailer air brake system. The mixing control valve (9) can be triggered when the main vehicle oil brake system supplies oil to drive the trailer air brake system to perform a braking action; A pre-brake control valve (7) is connected between the air source device (1) and the mixing control valve (9) in a normally closed state and can be opened when triggered. When the pre-brake control valve (7) is opened, the gas of the air source device (1) can be introduced into the mixing control valve (9) to trigger the mixing control valve (9) to drive the trailer air brake system to perform a braking action; and The brake operating mechanism is connected to the pre-brake control valve (7) and is used to trigger the pre-brake control valve (7) and the mixed control valve (9) to work together when being operated, so that the trailer air brake system and the main vehicle oil brake system can perform braking actions in sequence.

2. The pre-braking system according to claim 1, characterized in that: The mixing control valve (9) comprises a valve housing (91), a valve core mechanism arranged in a housing cavity of the valve housing (91), and a main air inlet end (92), a main air outlet end (93), an air inlet control end (94), an oil inlet control end (95), an air outlet energy supply end (97), and an air outlet control end (98) arranged on a housing wall of the valve housing (91) and respectively connected to the housing cavity; The air outlet energy supply end (97) and the air outlet control end (98) are both used to connect to the trailer air brake system, the main air inlet end (92) is connected to the air source device (1), the air inlet control end (94) is connected to the air source device (1) via the pre-brake control valve (7), and the oil inlet control end (95) is used to connect to the main vehicle oil brake system, and the air inlet control end (94) and the oil inlet control end (95) can be triggered when input pressure is applied to control the valve core mechanism to move from a first valve core position to a second valve core position; When the first valve core is in the position, the outlet control end (98) is connected to the main exhaust end (93), and the main intake end (92) is disconnected from the outlet control end (98); when the second valve core is in the position, the outlet control end (98) is disconnected from the main exhaust end (93), and the main intake end (92) is connected to both the outlet energy supply end (97) and the outlet control end (98).

3. The pre-braking system according to claim 2, characterized in that: The pre-brake system further comprises a pressure limiting valve (8), and the pre-brake control valve (7) is connected to the air intake control end (94) via the pressure limiting valve (8); and / or, the pre-brake system further comprises an air storage device (5), and the air source device (1) is connected to the pre-brake control valve (7) and the main air intake end (92) via the air storage device (5).

4. The pre-braking system according to claim 2, characterized in that: The oil inlet control end (95) comprises a first oil inlet control end (95a) and a second oil inlet control end (95b) respectively used to connect the left oil brake system and the right oil brake system in the main vehicle oil brake system; the brake operating mechanism comprises a left brake operating mechanism and a right brake operating mechanism; the left brake operating mechanism can trigger the pre-brake control valve (7) to open when being operated and drive the left oil brake system to operate so that the air inlet control end (94) and the first oil inlet control end (95a) are triggered in sequence; the right brake operating mechanism can trigger the pre-brake control valve (7) to open when being operated and drive the right oil brake system to operate so that the air inlet control end (94) and the second oil inlet control end (95b) are triggered in sequence.

5. The pre-braking system according to claim 1, characterized in that: The pre-brake system further comprises a drying device (2), the drying device (2) comprising a drying air inlet, a drying air outlet, a heater and a temperature sensor, the drying air inlet being connected to the air source device (1), the drying air outlet being connected to the pre-brake control valve (7) and the mixing control valve (9), the temperature sensor being used to monitor the internal temperature of the drying device (2), and the heater being configured to be turned on when the internal temperature is less than a preset critical temperature and turned off when the internal temperature is not less than the preset critical temperature.

6. The pre-braking system according to claim 1, characterized in that: The pre-brake system further comprises a drying device (2) and a regeneration air storage device (3), wherein the drying device (2) comprises a drying air inlet, a drying air outlet and a regeneration air outlet, wherein the drying air inlet is connected to the air source device (1), and the drying air outlet is connected to the pre-brake control valve (7) and the mixing control valve (9), and the regeneration air storage device (3) is connected to the regeneration air outlet and is capable of blowing gas back to the drying device (2).

7. The pre-braking system according to claim 1, characterized in that: The pre-braking system further comprises a drying device (2) and a silencer (4), wherein the drying device (2) comprises a drying air inlet, a drying air outlet and a relief valve, wherein the relief valve is connected between the drying air inlet and the drying air outlet, and the silencer (4) is connected to the air outlet end of the relief valve.

8. The pre-braking system according to claim 1, characterized in that: The pre-braking system further comprises: A parking control valve (11) is used to be connected between the transmission hydraulic system and the mixing control valve (9) in a normally closed state, and can be opened when triggered to conduct the transmission hydraulic system and the mixing control valve (9); The parking control mechanism is used to stop triggering the parking control valve (11) when being operated so as to cut off the conduction between the transmission hydraulic system and the mixing control valve (9), and the mixing control valve (9) can be triggered when the parking control valve (11) is switched from an open state to a closed state so as to control both the trailer air brake system and the main vehicle oil brake system to perform a braking action.

9. The pre-braking system according to claim 2, characterized in that: The pre-braking system further comprises a first air pressure sensor (12) for monitoring the air pressure of the air outlet power supply end (97) and a second air pressure sensor (13) for monitoring the air pressure of the air outlet control end (98).

10. The pre-braking system according to claim 9, characterized in that: The mixing control valve (9) further comprises a throttling element (918) arranged between the main air inlet end (92) and the air outlet power supply end (97); when the valve core mechanism is in the second valve core position and the second air pressure sensor (13) detects that the air pressure at the air outlet control end (98) is less than the preset control air pressure, the main air inlet end (92) is connected to the air outlet power supply end (97) through the throttling element (918); when the valve core mechanism is in the second valve core position and the second air pressure sensor (13) detects that the air pressure at the air outlet control end (98) is not less than the preset control air pressure, the main air inlet end (92) is directly connected to the air outlet power supply end (97).

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