Hydraulic braking system and engineering vehicle

Abstract

The application relates to a brake device and discloses a hydraulic brake system and an engineering vehicle, wherein the hydraulic brake system comprises an oil inlet oil circuit and two brake oil circuits; a liquid filling valve and an energy storage device are sequentially arranged on the oil inlet oil circuit; the brake oil circuit comprises a manual brake oil circuit provided with a mechanical brake valve and an electric brake oil circuit provided with a driving electric brake valve; one end of the manual brake oil circuit and one end of the electric brake oil circuit are connected with the oil inlet oil circuit; the other end of the manual brake oil circuit is connected with a brake through a shuttle valve; the other end of the electric brake oil circuit is connected with the brake through the shuttle valve; and the manual brake oil circuit or the electric brake oil circuit is selectively communicated with the brake through the shuttle valve. The brake system can realize the brake function in manual operation and the automatic brake function in unmanned driving, can guarantee the synchronization of the two brake circuits, and can avoid the rollover and other dangers caused by the failure of one side when the left and right brakes are independently operated.

Description

TECHNICAL FIELD

[0001] The present application relates to a braking device, in particular to a hydraulic braking system. Furthermore, it also relates to an engineering vehicle with the hydraulic braking system. BACKGROUND

[0002] With the development of economy, the construction and maintenance of infrastructure is becoming more and more important, and the market needs off-highway vehicles to undertake these work with better performance in braking, higher reliability, and smaller installation space.

[0003] The traditional braking configuration is air over hydraulic braking system, which has the advantages of low cost, and the disadvantages of low reliability. Since the air over hydraulic braking system needs to continuously suck air from the atmosphere for compression, store the compressed gas, and release the energy stored in the compressed gas through a control valve for braking when the vehicle needs to brake, other substances in the atmosphere that are not conducive to the braking system, such as moisture and dust, will inevitably enter the braking system, and dust can easily block the pipeline and cause the braking system to fail. At the same time, moisture in the atmosphere can easily freeze at low temperatures, causing the dryer and air valve of the air over hydraulic braking system to freeze, resulting in failure of the braking system. Secondly, the air over hydraulic braking system has poor performance, since the air braking system uses about 10 bar of compressed air to achieve braking, and due to the strong compressibility of the gas, the process of establishing pressure in the pipeline is relatively slow, which leads to a slow process of establishing the braking torque of the brake, and a long braking distance. Thirdly, the air over hydraulic braking system has a large installation space. Since the compressed gas needs to be stored, and the pressure of the compressed gas is not high, the space of the gas tank for storing the gas is large, which leads to the whole braking system not being suitable for compact vehicle layout.

[0004] At present, the above technical problems are solved by a full hydraulic braking system, which is a fully closed system and does not need to suck air from the atmosphere during operation, thus avoiding the entry of impurities from the atmosphere into the system, greatly improving the reliability of the system. Secondly, due to the strong rigidity and low compressibility of hydraulic oil, the time for establishing pressure in the braking system is shorter, making the braking system more responsive. Thirdly, the energy storage system of the full hydraulic braking system is high pressure, usually 100-200 bar, which is much higher than the energy storage pressure of about 10 bar of the air over hydraulic braking system, and the energy density of the energy storage is large, greatly reducing the volume of the accumulator for energy storage.

[0005] Specifically, the full hydraulic brake system comprises a liquid filling valve, a brake valve and a caliper disc service brake. The liquid filling valve is connected with two accumulators through pipelines, and the oil outlets of the accumulators are connected to the oil inlets of the double brake valve through pipelines. The service brake is realized by the action of the brake valve to control the caliper disc service brake. However, if an accident occurs and one accumulator fails, the two brakes will not work synchronously during high-speed braking, and there is a risk of rollover. SUMMARY

[0006] The technical problem to be solved by the present application is to provide a hydraulic brake system which can realize the brake function when manually operated and the automatic brake function when unmanned, can ensure the synchronization of two brake paths, and can avoid rollover and other dangers caused by the failure of one side when the brakes on the left and right sides are independent.

[0007] The technical problem to be solved by the present application is to provide a hydraulic brake system which can realize the brake function when manually operated and the automatic brake function when unmanned, can ensure the synchronization of two brake paths, and can avoid rollover and other dangers caused by the failure of one side when the brakes on the left and right sides are independent.

[0008] To solve the above technical problems, the present application provides a hydraulic brake system, comprising an oil inlet oil path and two brake oil paths, wherein the oil inlet oil path is sequentially provided with a liquid filling valve and an energy storage device, the brake oil path comprises a manual brake oil path provided with a mechanical brake valve and an electric control brake oil path provided with a service electric control brake valve, one end of the manual brake oil path and one end of the electric control brake oil path are connected with the oil inlet oil path, the other end of the manual brake oil path is connected with a brake through a shuttle valve, and the other end of the electric control brake oil path is connected with the brake through the shuttle valve, so as to selectively make the manual brake oil path or the electric control brake oil path communicate with the brake through the shuttle valve.

[0009] Optionally, the brake oil path further comprises a parking automatic switching brake oil path provided with a parking electric control brake valve, one end of the parking automatic switching brake oil path is connected with the oil inlet oil path, and the other end of the parking automatic switching brake oil path is connected with the brake.

[0010] Optionally, a low-pressure alarm device is arranged between the liquid filling valve and the energy storage device.

[0011] Optionally, the liquid filling valve comprises a liquid filling directional valve, an oil supply oil path and a pilot valve, one end of the oil supply oil path is connected with the energy storage device, the other end is connected with a working oil port of the liquid filling directional valve, one end control cavity of the liquid filling directional valve is connected with a working oil port of the pilot valve, the other end control cavity of the liquid filling directional valve is connected with an oil inlet of the liquid filling directional valve, the oil inlet of the pilot valve is connected with the oil supply oil path, and the oil return port of the pilot valve and the oil drain port of the liquid filling directional valve are connected with an oil return oil path.

[0012] Further, a one-way valve is arranged on the oil supply oil path.

[0013] Optionally, a pressure detection device is arranged on the oil path between the brake oil path and the brake.

[0014] Optionally, a tail light switch is arranged on the oil path between the brake oil path and the brake.

[0015] Optionally, the oil inlet of the liquid filling valve is connected with a hydraulic pump through a filter.

[0016] Optionally, the manual control ends of the two mechanical brake valves are fixedly connected to realize synchronous braking.

[0017] In another aspect, the application provides an engineering vehicle provided with the hydraulic brake system.

[0018] Through the above technical solution, the application has the following advantages:

[0019] The application comprises two brake oil paths, which are respectively used for braking wheels on the left side and the right side of the vehicle, and the brake oil path comprises a manual brake oil path and an electric brake oil path, the manual brake oil path and the electric brake oil path are connected with the brake through a shuttle valve, when manual operation is performed, the manual brake function can be realized by controlling the mechanical brake valve on the manual brake oil path, and when no one drives, the automatic brake function can be realized by controlling the electric brake valve. Moreover, the left and right brakes are independent of each other, and unilateral braking can be realized, when unilateral manual braking or automatic braking fails, the shuttle valve is selectively connected with the brake, so that the synchronization of the two brake paths is ensured, and the risk of rollover caused by unilateral failure when the left and right brakes are independent is avoided.

[0020] Other features and advantages of the application will be described in detail in the following specific embodiments. BRIEF DESCRIPTION OF DRAWINGS

[0021] The accompanying drawings are included to provide a further understanding of the application, and constitute a part of the specification, and are used together with the following specific embodiments to explain the application, but do not constitute a limitation on the application. In the drawings:

[0022] Figure 1 is the hydraulic principle diagram of the hydraulic brake system in the embodiment of the present application.

[0023] Explanation of reference signs

[0024] 1 oil tank 2 hydraulic pump

[0025] 3 filter 4 liquid filling valve

[0026] 41 liquid filling reversing valve 42 pilot valve

[0027] 5 low pressure alarm device 6 energy storage device

[0028] 7 mechanical brake valve 8 shuttle valve

[0029] 9 parking electric control brake valve 10 driving electric control brake valve

[0030] 11 pressure detection device 12 tail light switch

[0031] 13 brake EMBODIMENT

[0032] The embodiment of the present application will be described in detail below with reference to the accompanying drawings. It should be understood that the embodiment described herein is only used to illustrate and explain the present application, and is not used to limit the present application.

[0033] In the description of the present application, it should be noted that unless otherwise explicitly specified and limited, the terms "arranged", "connected" should be understood broadly, for example, it can be fixedly connected, or detachably connected, or integrally connected; it can be directly connected, or indirectly connected through an intermediate medium, or the internal communication of two elements or the interaction relationship between two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0034] First of all, it should be noted that the hydraulic brake system of the present application belongs to the field of hydraulic pressure, and for those skilled in the art, the essential technical concept lies in the hydraulic connection relationship. Related hydraulic elements, such as reversing valve, shuttle valve, filter, brake, etc. are well known to those skilled in the art, and are also common components in existing hydraulic systems, so the following description of these hydraulic elements will be brief. After knowing the technical concept of the present application, those skilled in the art can also simply replace the oil circuit or valve, etc. to realize the function of the hydraulic brake system of the present application, which also belongs to the protection scope of the present application.

[0035] Reference Figure 1The hydraulic brake system of the basic technical scheme of the application comprises an oil inlet oil path and two brake oil paths, the oil inlet oil path is sequentially provided with a liquid filling valve 4 and an energy storage device 6, the energy storage device 6 is supplied with hydraulic oil through the liquid filling valve 4, and the energy storage device 6 provides the brake oil path with hydraulic oil required for braking, the brake oil path comprises a manual brake oil path and an electric brake oil path, the manual brake oil path is provided with a mechanical brake valve 7, the electric brake oil path is provided with a travel electric brake valve 10, one end of the manual brake oil path is connected with the oil inlet oil path, the other end of the manual brake oil path is connected with a brake 13 through a shuttle valve 8, one end of the electric brake oil path is also connected with the oil inlet oil path, the other end of the electric brake oil path is connected with the brake 13 through the shuttle valve 8, so as to selectively make the manual brake oil path or the electric brake oil path communicate with the brake 13 through the shuttle valve 8. When manual operation is performed, the electric brake oil path can be cut off through the travel electric brake valve 10, the hydraulic oil in the energy storage device 6 flows to the brake 13 through the mechanical brake valve 7 and the shuttle valve 8 by manual control of the mechanical brake valve 7 by an operator, so as to realize braking of the wheels on the left side or the right side of the vehicle or synchronous braking of the wheels on the left and right sides. When the vehicle is in an unmanned state, the hydraulic oil in the energy storage device 6 flows to the brake 13 through the travel electric brake valve 10 and the shuttle valve 8 by control of the corresponding electric brake oil path by the travel electric brake valve 10 by the operator, so as to realize braking of the wheels on the left side or the right side of the vehicle or synchronous braking of the wheels on the left and right sides. By arranging the shuttle valve 8, manual braking and automatic braking can be conveniently switched. Moreover, if manual braking on one side fails during vehicle driving, the corresponding automatic braking can be directly switched to, the synchronism of braking on the two sides is ensured, and the risk of rollover due to failure of one side when braking on the left and right sides is independent is avoided. The energy storage device 6 is preferably an accumulator.

[0036] Generally, the hydraulic pump 2 is arranged to suck hydraulic oil from the oil tank 1 and discharge the hydraulic oil to the liquid filling valve 4. Specifically, a filter 3 can be arranged between the hydraulic pump 2 and the liquid filling valve 4 to filter the hydraulic oil, so as to meet the cleanliness requirement of the hydraulic oil. The hydraulic pump 2 is preferably a gear pump.

[0037] Further, the long-time parking automatic switching parking brake mode can also be set, specifically, the brake oil circuit further comprises a parking automatic switching brake oil circuit, the parking automatic switching brake oil circuit is provided with a parking electric control brake valve 9, one end of the parking automatic switching brake oil circuit is connected with the oil inlet oil circuit, and the other end of the parking automatic switching brake oil circuit is connected with the brake 13. The parking electric control brake valve 9 is connected with a control unit in a control system of the vehicle, when the control unit receives information that the vehicle is in a stationary state, the parking electric control brake valve 9 is controlled to be de-energized, at this time, the parking automatic switching brake oil circuit is conducted, so that the hydraulic oil in the energy storage device 6 flows to the brake 13 through the parking electric control brake valve 9 and the shuttle valve 8, thereby realizing automatic parking of the whole vehicle when the vehicle is stationary for a long time, when the control unit receives information that the vehicle is started or in a driving state, the parking electric control brake valve 9 is controlled to be energized, at this time, the parking automatic switching brake oil circuit is cut off, thereby releasing the brake of the vehicle.

[0038] It should be noted that for the engineering vehicle, the control unit in the engineering vehicle is generally a conventional component, on this basis, various electric control elements in the hydraulic brake system of the present application are electrically connected to the control unit, and the control unit is controlled based on the detection signal, under the inspiration of the technical concept of the present application, which is relatively mature in the realization of control technology.

[0039] In specific embodiments, the hydraulic oil is timely supplemented to the accumulator 6 by the liquid filling valve 4 according to the storage amount of the hydraulic oil in the accumulator 6. Specifically, the liquid filling valve 4 comprises a liquid filling directional valve 41, an oil supply oil path, and a pilot valve 42, one end of the oil supply oil path is connected with the accumulator 6, the other end of the oil supply oil path is connected with a working oil port of the liquid filling directional valve 41, one end control chamber of the liquid filling directional valve 41 is connected with a working oil port of the pilot valve 42, the other end control chamber of the liquid filling directional valve 41 is connected with an oil inlet port of the liquid filling directional valve 41, the oil inlet port of the pilot valve 42 is connected with the oil supply oil path, the oil return port of the pilot valve 42 and the oil drain port of the liquid filling directional valve 41 are both connected with an oil return oil path. In the process of supplementing the hydraulic oil to the accumulator 6 by the liquid filling valve 4, the liquid filling valve 4 starts to supplement the hydraulic oil to the accumulator 6, the pressure in the accumulator 6 gradually reaches the liquid filling upper limit pressure setting of the liquid filling valve 4, the pressure acts on the control chamber of the pilot valve 42, pushes the pilot valve 42 to change direction, so that part of the hydraulic oil flows to the right control chamber of the liquid filling directional valve 41 through the oil inlet port and the working oil port of the pilot valve 42, and pushes the liquid filling directional valve 41 to change direction, so that the oil inlet port of the liquid filling directional valve 41 is communicated with the oil drain port, and the hydraulic oil flowing from the oil inlet port P of the liquid filling valve 4 to the liquid filling directional valve 41 is returned to the tank through the oil drain port O of the liquid filling valve 4; when the pressure in the accumulator 6 gradually decreases to the liquid filling lower limit pressure setting of the liquid filling valve 4 after multiple braking, at this time, the pressure acting on the control chamber of the pilot valve 42 decreases, the pilot valve 42 changes direction, so that the working oil port of the pilot valve 42 is communicated with the oil return port, so that the right control chamber of the liquid filling directional valve 41 is communicated with the oil return oil path through the pilot valve 42 and the oil return port T of the liquid filling valve 4, and the liquid filling directional valve 41 changes to the right position to start supplementing the hydraulic oil to the accumulator 6 through the liquid filling directional valve 41. Such a cycle is repeated to realize the timely supplement of the hydraulic oil to the accumulator 6.

[0040] In the oil supply oil path, a one-way valve is arranged to control the one-way flow of the hydraulic oil from the liquid filling directional valve 41 to the accumulator 6, and further, a throttle valve and a filter and other hydraulic elements are arranged in the oil supply oil path. An overflow valve can be arranged between the oil inlet port of the liquid filling directional valve 41 and the oil return port of the liquid filling valve 4 to prevent the system pressure from being too high and protect the system safety.

[0041] Further, in order to ensure that the brake system can be stably supplied with oil, a low pressure alarm device 5 can be arranged between the liquid filling valve 4 and the accumulator 6 to monitor the pressure in the accumulator 6, and a pressure value or a pressure range can be set as a comparison reference for affecting the stable supply of the brake system when a fault occurs, and when the pressure in the accumulator 6 is lower than the set value, the low pressure alarm device 5 issues an alarm to remind the maintenance personnel to timely maintain. The low pressure alarm device 5 is a low pressure alarm switch, which can be a hydraulic alarm to monitor the pressure in the accumulator 6.

[0042] In specific embodiments, a pressure detection device 11 can be arranged on the oil line between the brake oil line and the brake 13 to monitor the pressure in the oil line. For example, during manual braking, if the pressure in the oil line is very low, it indicates that the manual brake oil line corresponding to the oil line has a fault, and the pressure detection device 11 feeds back the pressure information to the control unit in time, and the control unit makes a judgment to control the driving electric control brake valve 10 on the corresponding side to start, and controls the brake 13 on the side to brake in time, to ensure the synchronization of the two brake lines, and avoid the risk of rollover due to the failure of one side when the left and right brakes are independent. Or, during automatic braking, if the pressure in the oil line is very low, it indicates that the electric control brake oil line corresponding to the oil line has a fault, and the pressure detection device 11 feeds back the pressure information to the control unit in time, and the control unit makes a judgment to start the parking electric control brake valve 9 in an emergency, and controls the brake 13 on the side to brake in time, to ensure the synchronization of the two brake lines, and avoid the risk of rollover due to the failure of one side when the left and right brakes are independent. The pressure detection device 11 is a hydraulic detection instrument, such as a pressure sensor.

[0043] In specific embodiments, the working state of the brake 13 can be indicated by light effects. Specifically, a tail light switch 12 can be arranged on the oil line between the brake oil line and the brake 13, when hydraulic oil flows to the brake 13, the hydraulic oil also flows through the tail light switch 12, the tail light switch 12 is controlled to turn on the tail light, and other road participants on the road are warned.

[0044] During manual braking, the mechanical brake valve 7 is generally a manually controlled hydraulic valve, such as being controlled by an operating handle or a foot pedal, and the operator controls the corresponding side mechanical brake valve 7 through the operating handle or the foot pedal to brake the wheels on the left or right side of the vehicle, to realize unilateral braking, and the left and right brakes are independent of each other. Alternatively, the two mechanical brake valves 7 can be mechanically connected, such as being fixedly connected by bolts, sleeves or other connecting members, and during manual braking control, the two-way synchronous braking can be realized.

[0045] In order to better understand the technical solutions and advantages of the present application, the following will be described in conjunction with relatively comprehensive technical features.

[0046] Reference Figure 1The preferred embodiment of the present application comprises an oil tank 1, a hydraulic pump 2, a filter 3, an oil inlet oil path and two brake oil paths, the oil inlet oil path is sequentially provided with a liquid filling valve 4 and an energy storage device 6, the oil tank 1, the hydraulic pump 2, the filter 3, the liquid filling valve 4 and the energy storage device 6 are sequentially connected, the energy storage device 6 is supplemented with hydraulic oil through the liquid filling valve 4, and the energy storage device 6 provides hydraulic oil required for braking to the brake oil path, a low-pressure alarm device 5 is installed on the oil path between the liquid filling valve 4 and the energy storage device 6, which is used to monitor the pressure in the energy storage device 6, the brake oil path comprises a manual brake oil path, an electric brake oil path and a parking automatic switching brake oil path, the manual brake oil path is provided with a mechanical brake valve 7, the parking automatic switching brake oil path is provided with a parking electric brake valve 9, the electric brake oil path is provided with a driving electric brake valve 10, one end of the manual brake oil path is connected with the oil inlet oil path, the other end of the manual brake oil path is connected with a brake 13 through a shuttle valve 8, one end of the parking automatic switching brake oil path is connected with the oil inlet oil path, the other end of the parking automatic switching brake oil path is connected with the brake 13, one end of the electric brake oil path is also connected with the oil inlet oil path, the other end of the electric brake oil path is connected with the brake 13 through the shuttle valve 8, a pressure detection device 11 can be arranged on the oil path between the brake oil path and the brake 13 to monitor the pressure in the oil path, a tail lamp switch 12 is arranged on the oil path between the brake oil path and the brake 13, and the working state of the brake 13 is indicated through the light effect. Wherein, the low-pressure alarm device 5 can be a low-pressure alarm switch, the energy storage device 6 is preferably an energy accumulator, and the pressure detection device 11 can be a pressure sensor.

[0047] By the technical scheme, when manual operation is performed, the electric control brake valve 10 can control the electric control brake oil path to be cut off, the operator controls the corresponding manual brake oil path to be conducted by the manual control brake valve 7, the hydraulic oil in the energy storage device 6 flows to the brake 13 through the manual control brake valve 7 and the shuttle valve 8, and thus the left or right wheel brake or the synchronous brake of the left and right wheels of the vehicle is realized. When the vehicle is unmanned, the operator controls the corresponding electric control brake oil path to be conducted by the electric control brake valve 10, the hydraulic oil in the energy storage device 6 flows to the brake 13 through the electric control brake valve 10 and the shuttle valve 8, and thus the left or right wheel brake or the synchronous brake of the left and right wheels of the vehicle is realized. By arranging the shuttle valve 8, the manual brake and the automatic brake can be conveniently switched. Moreover, during the vehicle running, if the manual brake of one side fails, the corresponding automatic brake can be directly switched to ensure the synchronization of the brakes of the two sides and avoid the risk of rollover due to the failure of one side when the brakes of the left and right sides are independent. When the control unit receives the information that the vehicle is in a stationary state, the parking electric control brake valve 9 is controlled to be not electrically connected, the hydraulic oil in the energy storage device 6 flows to the brake 13 through the parking electric control brake valve 9 and the shuttle valve 8, and thus the automatic parking of the whole vehicle during long-time stationary is realized. The hydraulic brake system of the present application is a manual + intelligent composite brake system, which is simple and reliable and can be applied to unmanned off-road vehicle systems.

[0048] On the basis of the technical scheme of the hydraulic brake system of the present application, the present application further provides an engineering vehicle, wherein the engineering vehicle comprises the hydraulic brake system according to any one of the technical schemes.

[0049] The preferred embodiments of the present application are described in detail above in combination with the drawings, but the present application is not limited to the specific details in the above embodiments, and various simple modifications can be made to the technical scheme of the present application within the technical concept of the present application, and these simple modifications all belong to the protection scope of the present application.

[0050] In addition, it should be noted that each specific technical feature described in the above specific embodiments can be combined in any appropriate manner without contradiction. In order to avoid unnecessary repetition, the present application will not further describe various possible combinations.

[0051] In addition, various different embodiments of the present application can also be combined in any appropriate manner, as long as they do not deviate from the idea of the present application, and they should also be considered as disclosed by the present application.

Claims

1. A hydraulic brake system characterized by, The hydraulic brake system comprises an oil inlet oil path and two brake oil paths, the oil inlet oil path is sequentially provided with a filling valve (4) and an energy storage device (6), any brake oil path comprises a manual brake oil path provided with a mechanical brake valve (7) and an electric brake oil path provided with a driving electric brake valve (10), one end of the manual brake oil path and one end of the electric brake oil path are connected with the oil inlet oil path, the other end of the manual brake oil path is connected with a brake (13) through a shuttle valve (8), the other end of the electric brake oil path is connected with the brake (13) through the shuttle valve (8), the manual brake oil path or the electric brake oil path is selectively communicated with the brake (13) through the shuttle valve (8), when manual operation is performed, the driving electric brake valve (10) is used for controlling the electric brake oil path to be cut off; when the vehicle is in a self-driving state, the driving electric brake valve (10) is used for controlling the electric brake oil path to be turned on. The brake oil path further comprises a parking automatic switching brake oil path provided with a parking electric brake valve (9), one end of the parking automatic switching brake oil path is connected with the oil inlet oil path, and the other end thereof is connected with the brake (13). A pressure detection device (11) is arranged on an oil path between the brake oil path and the brake (13), the pressure detection device (11) is located between the shuttle valve (8) and the brake (13), and the pressure detection device (11) is adapted to feed back pressure information to a control unit, so that the control unit can control the parking electric brake valve (9) according to the oil pressure signal.

2. The hydraulic brake system of claim 1, wherein, A low-pressure alarm device (5) is arranged between the filling valve (4) and the energy storage device (6).

3. The hydraulic brake system of claim 1, wherein, The filling valve (4) comprises a filling reversing valve (41), an oil supply oil path and a pilot valve (42), one end of the oil supply oil path is connected with the energy storage device (6), the other end thereof is connected with a working oil port of the filling reversing valve (41), one end of a control cavity of the filling reversing valve (41) is connected with a working oil port of the pilot valve (42), the other end of the control cavity of the filling reversing valve (41) is connected with an oil inlet port of the filling reversing valve (41), an oil inlet port of the pilot valve (42) is connected with the oil supply oil path, and a return oil port of the pilot valve (42) and a drain port of the filling reversing valve (41) are connected with a return oil path.

4. The hydraulic brake system of claim 3, wherein, A check valve is arranged on the oil supply oil path.

5. The hydraulic brake system according to any one of claims 1 to 4, characterized in that, A tail lamp switch (12) is arranged on an oil path between the brake oil path and the brake (13).

6. The hydraulic brake system according to any one of claims 1 to 4, characterized in that An oil inlet port of the filling valve (4) is connected with a hydraulic pump (2) through a filter (3).

7. The hydraulic brake system according to any one of claims 1 to 4, characterized in that Manual control ends of the two mechanical brake valves (7) are fixedly connected to perform synchronous braking.

8. An engineering vehicle characterized by, The hydraulic brake system is provided in any one of claims 1 to 7.

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