Unmanned emergency hydraulic braking system for mine car

Abstract

The invention relates to an unmanned emergency hydraulic braking system for a mine car, which comprises a hydraulic oil tank, a hydraulic pump, an emergency braking valve, a pedal valve, two electro-hydraulic proportional braking valves and a brake, and the two oil inlet ends of the pedal valve are respectively connected with the oil inlet ends of the two electro-hydraulic proportional braking valves; the two oil outlet ends are connected with the oil outlet ends of the two electro-hydraulic proportional brake valves through the two shuttle valves respectively, and the emergency brake valve is connected with the hydraulic control end of the pedal valve. The input ends of the brakes are connected with the pedal valve and the electro-hydraulic proportional brake valve through the shuttle valve, the shuttle valve respectively compares the output pressure of the pedal valve and the output pressure of the electro-hydraulic proportional brake valve and outputs the larger pressure to the two brakes, and emergency braking under the working conditions that the pressure of the braking system is smaller than a set value and the unmanned driving system is powered off is achieved; meanwhile, the emergency brake valve is arranged, pilot control oil of the pedal valve is output according to different working conditions, and the service life of hydraulic elements of the system is prolonged under the condition that effective operation of the system is guaranteed.

Description

Technical Field

[0001] The invention relates to the technical field of mining machinery, in particular to an unmanned emergency hydraulic braking system for a mining vehicle. Background Art

[0002] Mining dump trucks are used for mining and transportation of ore in mines, and are widely used in large open-pit mining and earthwork construction projects. Mining dump trucks have a large load capacity and are often used in downhill conditions in mining areas. The hydraulic brake system composed of brake valves, pedal valves, brakes and other components is one of the core systems of mining dump trucks. With the promotion and application of intelligent mining and unmanned driving technology, more and more mining equipment has unmanned driving functions. The parking brake and service brake functions of the mine car are realized by the wire-controlled hydraulic brake system, while the manual operation of the pedal valve is retained. In order to improve the safety and reliability of the mine car, the mine car adopts an emergency hydraulic brake system. Summary of the invention

[0003] The technical problem to be solved by the present invention is to overcome the deficiencies of the above-mentioned prior art and provide an unmanned emergency hydraulic braking system for a mine car, which can realize automatic emergency braking under abnormal conditions of low voltage and power failure when the mine car is unmanned.

[0004] The present invention is implemented by the following technical scheme: an unmanned mine car emergency hydraulic brake system includes a hydraulic oil tank and a hydraulic pump, the oil outlet of the hydraulic pump is divided into two paths, one is a front brake oil path for providing brake oil for the front wheel brake, and the other is a rear brake oil path for providing brake oil for the rear wheel brake; The front brake oil circuit includes a one-way valve I, a front brake accumulator and an electro-hydraulic proportional brake valve I connected in series, and the rear brake oil circuit includes a one-way valve II, a rear brake accumulator and an electro-hydraulic proportional brake valve II connected in series; It also includes a pedal valve, the two oil inlet ends of the pedal valve are respectively connected to the oil inlet ends of the electro-hydraulic proportional brake valve I and the electro-hydraulic proportional brake valve II, the two oil outlet ends of the pedal valve are respectively connected to the oil outlet ends of the electro-hydraulic proportional brake valve I and the electro-hydraulic proportional brake valve II through the shuttle valve II and the shuttle valve III, the oil outlet end of the shuttle valve II is connected to the front wheel brake, and the oil outlet end of the shuttle valve III is connected to the rear wheel brake; The hydraulic control end of the pedal valve is connected to a hydraulic control pilot valve, and the oil inlet end of the hydraulic control pilot valve is connected to the front brake accumulator and the rear brake accumulator through a shuttle valve I. The hydraulic control end of the hydraulic control pilot valve is connected to an electromagnetic reversing valve, and the oil inlet end of the electromagnetic reversing valve is connected to a hydraulic control reversing valve. The hydraulic control reversing valve is provided with two oil inlet ends, and the two oil inlet ends of the hydraulic control reversing valve are respectively connected to the oil outlet ends of the check valve I and the check valve II, and the hydraulic control end of the hydraulic control reversing valve is connected to the oil inlet end on the same side.

[0005] Furthermore, two groups of linked valve bodies are arranged in the pedal valve, the working position structures of the two groups of valve bodies are the same, the two oil inlet ends of the pedal valve are respectively connected to the oil inlet ends of the two groups of valve bodies, and the two oil outlet ends of the pedal valve are respectively the oil outlet ends of the two groups of valve bodies.

[0006] When there is no hydraulic oil at the hydraulic control end of the pedal valve, the oil inlet end and the oil outlet end of the pedal valve are not connected. When there is hydraulic oil at the hydraulic control end of the pedal valve, the oil inlet end and the oil outlet end of the pedal valve are connected.

[0007] The hydraulically controlled pilot valve is a two-position three-way hydraulically controlled valve. When the hydraulically controlled pilot valve is in the non-hydraulic control position, the oil inlet end of the hydraulically controlled pilot valve is connected to the hydraulic control end of the pedal valve. When the hydraulically controlled pilot valve is in the hydraulic control position, the hydraulic control end of the pedal valve is connected to the oil tank.

[0008] The preset pressure of the hydraulically controlled pilot valve is the same as the system setting value.

[0009] The electromagnetic reversing valve is a two-position three-way electromagnetic reversing valve. When the electromagnetic reversing valve is in an electric potential, the hydraulic control end of the hydraulic control pilot valve is connected to the oil outlet end of the hydraulic control reversing valve. When the electromagnetic reversing valve is in an electric potential-free state, the hydraulic control end of the hydraulic control pilot valve is connected to the oil tank.

[0010] The hydraulically controlled reversing valve is a three-position, three-way, double hydraulically controlled reversing valve. The middle position of the hydraulically controlled reversing valve is a two-way position. When the pressure at the left oil inlet end of the hydraulically controlled reversing valve is higher and the hydraulically controlled reversing valve works in the left position, the output end of the hydraulically controlled reversing valve is connected to the right oil inlet end.

[0011] The present invention has the following advantages: in the unmanned emergency hydraulic brake system of the mine car of the present invention, the input end of the brake is connected to the pedal valve and the electro-hydraulic proportional brake valve through a shuttle valve, the shuttle valve compares the output pressures of the pedal valve and the electro-hydraulic proportional brake valve respectively and outputs the larger pressure to the front wheel brake and the rear wheel brake respectively, so as to realize emergency braking under the condition that the brake system pressure is less than the set value and the unmanned driving system is powered off; at the same time, an emergency brake valve is provided to output the pilot control oil of the pedal valve according to different working conditions, so as to avoid unnecessary components from being added to the work while ensuring the effective operation of the system, thereby improving the service life of the hydraulic components of the system. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] The accompanying drawings are part of the present invention and are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention, but do not constitute an improper limitation of the present invention. Obviously, the accompanying drawings described below are only some embodiments. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without creative work.

[0013] In the attached picture: Figure 1 It is the hydraulic principle diagram of the present invention.

[0014] In the figure: 1. oil tank, 2. hydraulic pump, 3. non-return valve I, 4. non-return valve II, 5. hydraulically controlled reversing valve, 6. solenoid reversing valve, 7. shuttle valve I, 8. hydraulically controlled pilot valve, 9. pedal valve, 10. electro-hydraulic proportional brake valve I, 11. shuttle valve II, 12. front wheel brake, 13. rear wheel brake, 14. shuttle valve III, 15. electro-hydraulic proportional brake valve II, 16. rear brake accumulator, 17. front brake accumulator, 18. emergency brake valve.

[0015] It should be noted that these drawings and textual descriptions are not intended to limit the conceptual scope of the present invention in any way, but are intended to illustrate the concept of the present invention for those skilled in the art by referring to specific embodiments. DETAILED DESCRIPTION

[0016] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. The following embodiments are used to illustrate the present invention but are not used to limit the scope of the present invention.

[0017] In the description of the present invention, it should be noted that the directions or positional relationships indicated by terms such as “upper”, “lower”, “front”, “back”, “left”, “right”, “vertical”, “inside” and “outside” are based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as a limitation on the present invention.

[0018] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0019] like Figure 1The unmanned emergency hydraulic brake system of the mining vehicle shown in the figure comprises a hydraulic oil tank 1 and a hydraulic pump 2. The oil outlet of the hydraulic pump 2 is divided into two paths, one is a front brake oil path for providing brake oil for the front wheel brake 12, and the other is a rear brake oil path for providing brake oil for the rear wheel brake 13. The front brake oil path comprises a one-way valve I3, a front brake accumulator 17 and an electro-hydraulic proportional brake valve I10 connected in series, and the rear brake oil path comprises a one-way valve II4, a rear brake accumulator 16 and an electro-hydraulic proportional brake valve II 15; also includes a pedal valve 9, the two oil inlet ends of the pedal valve 9 are respectively connected to the oil inlet ends of the electro-hydraulic proportional brake valve I10 and the electro-hydraulic proportional brake valve II15, the two oil outlet ends of the pedal valve 9 are respectively connected to the oil outlet ends of the electro-hydraulic proportional brake valve I10 and the electro-hydraulic proportional brake valve II15 through a shuttle valve II11 and a shuttle valve III14, the oil outlet end of the shuttle valve II11 is connected to the front wheel brake 12, and the oil outlet end of the shuttle valve III14 is connected to the rear wheel brake 13. The unmanned emergency hydraulic braking system of the mining car of the present invention has the same brake oil circuit settings for the front wheel brake and the rear wheel brake. Taking the front brake oil circuit of the front wheel brake as an example, the output end of the hydraulic pump is connected to the emergency brake valve 18, and the brake oil and the pilot control oil of the pedal valve are output through the emergency brake valve. The brake oil enters the input end of the pedal valve and the electro-hydraulic proportional brake valve I respectively. The pilot control oil controls whether the pedal valve is opened. The output ends of the electro-hydraulic proportional brake valve I and the pedal valve are connected to the shuttle valve II, and the output end of the shuttle valve II is connected to the front wheel brake. The emergency brake valve determines whether to output the pilot control oil of the pedal valve according to the system pressure and whether it is powered on. When the system is powered and the system pressure is higher than the set value, the emergency brake valve does not output the pilot control oil, and the brake oil of the front wheel brake is provided by the electro-hydraulic proportional brake valve I to achieve the control. movement; when the system has electricity and the system pressure is lower than the set value, the emergency brake valve outputs the rear brake accumulator and the front brake accumulator with the larger pressure as the pilot control oil, the pedal valve opens, and the brake oil of the front wheel brake is provided by the shuttle valve II after judgment, so as to achieve braking; when the system is powered off, the emergency brake valve outputs the pilot control oil, the pedal valve opens, and the brake oil of the front wheel brake is provided by the shuttle valve II after judgment, so as to achieve braking; in the unmanned driving state of the mine car of the present invention, an electromagnetic reversing valve is added, and its control program and valve body structure are simple and reliable; the emergency brake valve is used to control the pedal valve, and the pedal valve is connected in parallel with the electro-hydraulic proportional brake valve and combined with the shuttle valve to provide dual-circuit braking, thereby improving safety; at the same time, hydraulic automatic emergency braking is achieved by monitoring the hydraulic brake pressure state and power-off abnormal conditions, which is safe and effective.

[0020] like Figure 1In the unmanned emergency hydraulic braking system of the mining vehicle shown in the figure, the hydraulic control end of the pedal valve 9 is connected to the hydraulic control pilot valve 8, and the oil inlet end of the hydraulic control pilot valve 8 is connected to the front brake accumulator 17 and the rear brake accumulator 16 through the shuttle valve Ⅰ7, and the hydraulic control end of the hydraulic control pilot valve 8 is connected to the electromagnetic reversing valve 6, and the oil inlet end of the electromagnetic reversing valve 6 is connected to the hydraulic control reversing valve 5, and the hydraulic control reversing valve 5 is provided with two oil inlet ends, and the two oil inlet ends of the hydraulic control reversing valve 5 are respectively connected to the oil outlet ends of the one-way valve Ⅰ3 and the one-way valve Ⅱ4, and the hydraulic control end of the hydraulic control reversing valve 5 is connected to the oil inlet end on the same side. The hydraulic oil at the hydraulic control end of the pedal valve of the present invention is controlled by a hydraulic control pilot valve, and at the same time, the hydraulic oil at the hydraulic control end of the hydraulic control pilot valve is controlled by an electromagnetic reversing valve. When the mine car is unmanned and has electricity normally, the electromagnetic reversing valve is energized, and oil enters the hydraulic control end of the hydraulic control pilot valve. If the brake system pressure is greater than the set value, the hydraulic control pilot valve does not output hydraulic oil to the hydraulic control end of the pedal valve, and the hydraulic oil output by the hydraulic pump enters the two input ports of the pedal valve through the emergency brake valve and is cut off. The pressure oil reaches the inlets of the two electro-hydraulic proportional brake valves and is controlled by wire to perform normal braking functions. If the brake system pressure is lower than the set value, the hydraulic The hydraulic pilot valve outputs hydraulic oil to the hydraulic control end of the pedal valve, and the hydraulic pump outputs hydraulic oil through the emergency brake valve to enter the pedal valve control port to open the pedal valve, and the pedal valve pressure oil enters the front and rear wheel brakes through the front and rear shuttle valves for automatic emergency braking; when the mine car is unmanned and the power is cut off, the solenoid reversing valve is powered off, and there is no hydraulic oil at the hydraulic control end of the hydraulic pilot valve. The hydraulic pilot valve outputs hydraulic oil to the hydraulic control end of the pedal valve, and the hydraulic pump outputs hydraulic oil through the emergency brake valve to enter the pedal valve control port to open the pedal valve, and the pedal valve pressure oil enters the front and rear wheel brakes through the front and rear shuttle valves for automatic emergency braking.

[0021] like Figure 1 In the unmanned emergency hydraulic brake system of the mine car shown, the pedal valve 9 is provided with two groups of valve bodies in linkage, and the working position structures of the two groups of valve bodies are the same. The two oil inlet ends of the pedal valve 9 are respectively connected to the oil inlet ends of the two groups of valve bodies, and the two oil outlet ends of the pedal valve 9 are respectively the oil outlet ends of the two groups of valve bodies. The pedal valve of the present invention is provided with two valve bodies of the same structure and can be linked, and the oil inlet end of each valve body is connected to the two oil outlet ends of the emergency brake valve, and the oil outlet end of each valve body is connected to the shuttle valve II and the shuttle valve III. When the pedal valve is controlled by the hydraulic control end, the two groups of valve bodies act synchronously, and the two oil inlet ends and the two oil outlet ends of the pedal valve are connected and disconnected synchronously, so that the pedal valve can participate in the braking action of the front wheel brake and the rear wheel brake at the same time.

[0022] like Figure 1 In the unmanned emergency hydraulic brake system of the mining vehicle shown in the figure, when there is no hydraulic oil at the hydraulic control end of the pedal valve 9, the oil inlet end and the oil outlet end of the pedal valve 9 are not connected, and when there is hydraulic oil at the hydraulic control end of the pedal valve 9, the oil inlet end and the oil outlet end of the pedal valve 9 are connected. The pedal valve of the present invention is controlled by the hydraulic control end, and the opening and closing of the pedal valve is determined by whether there is pressure oil at the hydraulic control end.

[0023] like Figure 1 In the unmanned emergency hydraulic brake system of the mine car shown in the figure, the hydraulic pilot valve 8 is a two-position three-way hydraulic control valve. When the hydraulic pilot valve 8 is in the non-hydraulic control position, the oil inlet end of the hydraulic pilot valve 8 is connected to the hydraulic control end of the pedal valve 9. When the hydraulic pilot valve 8 is in the hydraulic control position, the hydraulic control end of the pedal valve 9 is connected to the oil tank 1. The oil outlet end of the hydraulic pilot valve of the present invention is connected to the hydraulic control end of the pedal valve, and the oil inlet end of the hydraulic pilot valve is connected to the shuttle valve I. The hydraulic pilot valve is controlled by the pressure of the hydraulic control end. When the pressure of the hydraulic control end is greater than the pressure of the spring end, the hydraulic pilot valve is in the left working position, the oil inlet end of the hydraulic pilot valve is cut off, and the hydraulic control end of the pedal valve is connected to the oil tank to return oil; when there is no pressure at the hydraulic control end of the hydraulic pilot valve or the pressure is less than the pressure at the spring end, the hydraulic pilot valve is in the right working position, the hydraulic pilot valve is connected to the hydraulic control end of the pedal valve and the shuttle valve I, and the hydraulic control end of the pedal valve flows into the pressure oil to control the pedal valve to start.

[0024] like Figure 1 In the unmanned emergency hydraulic brake system of the mine car shown in the figure, the preset pressure of the hydraulic pilot valve 8 is the same as the system setting value. The spring end pressure of the hydraulic pilot valve of the present invention is the same as the system setting value, and the hydraulic end pressure at the left end of the hydraulic pilot valve and the spring pressure at the right end are judged to realize the effect of automatic emergency braking according to the system pressure.

[0025] like Figure 1 In the unmanned emergency hydraulic brake system of the mining vehicle shown, the electromagnetic reversing valve 6 is a two-position three-way electromagnetic reversing valve. When the electromagnetic reversing valve 6 is in the state of being electrically conductive, the hydraulic control end of the hydraulic pilot valve 8 is connected to the oil outlet end of the hydraulic control reversing valve 5. When the electromagnetic reversing valve 6 is in the state of being non-electrically conductive, the hydraulic control end of the hydraulic pilot valve 8 is connected to the oil tank 1. The electromagnetic reversing valve of the present invention has two working positions. When the electromagnetic reversing valve is energized, it is in the right working position. The output end of the hydraulic control reversing valve is connected to the hydraulic control end of the hydraulic control pilot valve through the electromagnetic reversing valve. When the electromagnetic reversing valve is de-energized, it is in the left working position. The output end of the hydraulic control reversing valve is cut off at the electromagnetic reversing valve. The hydraulic control end of the hydraulic control pilot valve is connected to the oil return of the hydraulic oil tank.

[0026] like Figure 1In the unmanned emergency hydraulic braking system of the mining car shown in the figure, the hydraulically controlled reversing valve 5 is a three-position, three-way, double hydraulically controlled reversing valve, the middle position of the hydraulically controlled reversing valve 5 is a two-way position, and when the pressure at the left oil inlet end of the hydraulically controlled reversing valve 5 is higher and it works in the left position, the output end of the hydraulically controlled reversing valve 5 is connected to the right oil inlet end. The hydraulically controlled reversing valve of the present invention is provided with three working positions and two oil inlet ends, the middle position is a double-pass position, the left working position and the right working position are symmetrically arranged, the left oil inlet end is connected with the left hydraulic control end, and the right oil inlet end is connected with the right hydraulic control end. The working position of the hydraulically controlled reversing valve is determined according to the pressure of the left oil inlet end and the right oil inlet end. Among them, when in the left working position, the right oil inlet end is connected with the output end of the valve body, that is, when the pressure of the left oil inlet end is greater than the pressure of the right oil inlet end, the hydraulically controlled reversing valve is in the left working position, and the pressure oil of the right oil inlet end is output at the same time, so that the pressure oil with a lower pressure value is input into the hydraulically controlled pilot valve, ensuring that the system can effectively realize automatic emergency braking under low-pressure conditions, thereby improving the safety of the use of the unmanned driving system of the mine car.

[0027] like Figure 1 The unmanned emergency hydraulic brake system of the mine car shown in the figure is provided with brake hydraulic oil for the front wheel brake and the rear wheel brake by the hydraulic pump. The hydraulic oil is divided into two paths through the hydraulic pump. One path is divided into five paths after passing through the one-way valve I, and is respectively connected to the hydraulic control reversing valve, shuttle valve I, front brake accumulator 1, pedal valve and electro-hydraulic proportional brake valve I; the other path is divided into five paths after passing through the one-way valve II, and is respectively connected to the hydraulic control reversing valve, shuttle valve I, rear brake accumulator, pedal valve and electro-hydraulic proportional brake valve II. Automatic emergency braking is realized in the case of low voltage and power failure abnormal working conditions when there is no driver. The specific working process is as follows: When the minecart is unmanned and has power: 1. If the brake system pressure is greater than the set value, the hydraulic pump 2 outputs the pressure oil through the one-way valve Ⅰ3 and the one-way valve Ⅱ4 to the hydraulic control reversing valve 5. Since the system is powered at this time, the electromagnetic reversing valve 6 is powered and is in the right position. The pressure oil output by the hydraulic control reversing valve 5 reaches the hydraulic control end of the hydraulic control pilot valve 8 through the right position of the electromagnetic reversing valve 6. The pressure at the hydraulic control end of the hydraulic control pilot valve 8 is greater than the right spring pressure, that is, greater than the system set value. The hydraulic control pilot valve 8 is in the left position, and the pressure oil output through the one-way valve Ⅰ3 and the one-way valve Ⅱ4 flows from the shuttle valve 7 to the left position of the hydraulic control pilot valve 8 and is cut off; after passing through the one-way valve Ⅰ3 and the one-way valve Ⅱ The pressure oil outputted by the hydraulic control valve 4 also flows to the pedal valve 9, the electro-hydraulic proportional brake valve I 10, the electro-hydraulic proportional brake valve II 15, the rear brake accumulator 16 and the front brake accumulator 17 respectively. Among them, since there is no pressure oil at the hydraulic control end of the pedal valve 9, the pedal valve 9 is not moved and is in the non-conducting working position, and the pressure oil to the pedal valve 9 is cut off; the pressure oil to the electro-hydraulic proportional brake valve I 10 and the electro-hydraulic proportional brake valve II 15 is controlled by wire control, and the front and rear brake pressure oils are outputted to the front wheel brake 12 and the rear wheel brake 13 respectively through the shuttle valve II 11 and the shuttle valve III 14 to meet the normal braking function of unmanned driving.

[0028] 2. If the brake system pressure is less than the set value, the pressure oil output by the hydraulic pump 2 reaches the hydraulically controlled reversing valve 5, the solenoid reversing valve 6, the shuttle valve I7, the hydraulically controlled pilot valve 8, the pedal valve 9, the electro-hydraulic proportional brake valve I10, the electro-hydraulic proportional brake valve II15, the rear brake accumulator 16 and the front brake accumulator 17 through the one-way valve I3 and the one-way valve II4 respectively. If the pressure of the front brake accumulator 17 connected to the left pilot of the hydraulically controlled reversing valve 5 is lower than the pressure of the rear brake accumulator 16 connected to the right pilot of the hydraulically controlled reversing valve 5, the right pilot pressure of the hydraulically controlled reversing valve 5 is greater than the left pilot pressure and is in the right position. The pressure oil output by the front brake accumulator 17 reaches the electromagnetic reversing valve 6 through the right position of the hydraulically controlled reversing valve 5. At this time, the electromagnetic reversing valve 6 is energized and is in the right position. The pressure oil output by the hydraulically controlled reversing valve 5 reaches the pilot control port of the hydraulically controlled pilot valve 8 through the right position of the electromagnetic reversing valve 6. The pressure of the pilot control port of the hydraulically controlled pilot valve 8 is that the pressure of the front brake accumulator 17 is lower than the set value, and the hydraulically controlled pilot valve 8 is in the right position. At this time, the pressure oil output by the front brake accumulator 17 and the rear brake accumulator 16 passes through the shuttle valve I7, and the shuttle valve I7 outputs the pressure oil of the rear brake accumulator 16, and outputs the pressure oil to the pilot control port of the pedal valve 9 through the right position of the hydraulically controlled pilot valve 8 and opens the pedal valve 9. At this time, the pressure oil output by the front brake accumulator 17 and the rear brake accumulator 16 is respectively sent to the shuttle valve II 11 and the shuttle valve III 14 through the pedal valve 9. At this time, the pressure output by the electro-hydraulic proportional brake valve 10 and the electro-hydraulic proportional brake valve 15 is less than or equal to the pressure output by the pedal valve 9 and is respectively sent to the shuttle valve II 11 and the shuttle valve III 14. The shuttle valve II 11 and the shuttle valve III 14 respectively output the pressure of the pedal valve 9 to the front wheel brake 12 and the rear wheel brake 13 to complete the automatic emergency braking. If the pressure of the front brake accumulator 17 connected to the left pilot of the hydraulic control reversing valve 5 is higher than the pressure of the rear brake accumulator 16 connected to the right pilot of the hydraulic control reversing valve 5, the right pilot pressure of the hydraulic control reversing valve 5 is less than the left pilot pressure and is in the left position. The pressure oil output by the rear brake accumulator 16 is transferred to the electromagnetic reversing valve 6 through the left position of the hydraulically controlled reversing valve 5. The pilot control port pressure of the hydraulically controlled pilot valve 8 is lower than the set value when the pressure of the rear brake accumulator 16 is in the right position. The pressure oil output by the front brake accumulator 17 and the rear brake accumulator 16 is transferred to the front brake accumulator 17 through the shuttle valve I7. The rest is the same as above to complete the automatic emergency braking.

[0029] When the minecart is unmanned and loses power: The hydraulic pump 2 outputs pressure oil through the one-way valve Ⅰ3 and the one-way valve Ⅱ4 to the hydraulic control reversing valve 5, the electromagnetic reversing valve 6, the shuttle valve Ⅰ7, the hydraulic control pilot valve 8, the pedal valve 9, the electro-hydraulic proportional brake valve Ⅰ10, the electro-hydraulic proportional brake valve Ⅱ15, the rear brake accumulator 16 and the front brake accumulator 17. At this time, the electromagnetic reversing valve 6 is powered off and is in the left position, and the pressure oil of the pilot control port of the hydraulic control pilot valve 8 flows back to the oil tank through the left position of the electromagnetic reversing valve 6. The pilot pressure of the hydraulic control pilot valve 8 is lower than the set value and is in the right position. The pressure oil output by the shuttle valve Ⅰ7 flows through the right position of the hydraulic control pilot valve 8 to the pilot control port of the pedal valve 9 and opens the pedal valve 9. The pedal valve 9 outputs pressure to the shuttle valve II 11 and the shuttle valve III 14 respectively. At this time, the pressure output by the electro-hydraulic proportional brake valve I 10 and the electro-hydraulic proportional brake valve II 15 when the power is cut off is less than or equal to the pressure output by the pedal valve 9 and goes to the shuttle valve II 11 and the shuttle valve III 14 respectively. The shuttle valve II 11 and the shuttle valve III 14 respectively output the pressure of the pedal valve 9 to the front wheel brake 12 and the rear wheel brake 13 to complete automatic emergency braking.

[0030] In the description provided herein, a large number of specific details are described. However, it is understood that embodiments of the present invention can be practiced without these specific details. In some instances, well-known methods, structures and techniques are not shown in detail so as not to obscure the understanding of this description.

[0031] In addition, those skilled in the art will understand that, although some embodiments described herein include certain features included in other embodiments but not other features, the combination of features of different embodiments also means being within the scope of protection of the present invention and forming different embodiments. For example, in the above embodiments, those skilled in the art can use them in combination according to the known technical solutions and the technical problems to be solved by this application.

[0032] The above is only a preferred embodiment of the present invention, and does not limit the present invention in any form. Although the present invention has been disclosed as a preferred embodiment as above, it is not used to limit the present invention. Any technician familiar with this patent can make some changes or modify the technical contents suggested above into equivalent embodiments without departing from the scope of the technical solution of the present invention. However, any simple modification, equivalent change and modification made to the above embodiments according to the technical essence of the present invention without departing from the content of the technical solution of the present invention still fall within the scope of the solution of the present invention.

Claims

1. The unmanned emergency hydraulic brake system of the mine car is characterized by: It includes a hydraulic oil tank 1 and a hydraulic pump 2. The oil outlet of the hydraulic pump 2 is divided into two paths, one is a front brake oil path for providing brake oil for the front wheel brake 12, and the other is a rear brake oil path for providing brake oil for the rear wheel brake 13; The front brake oil circuit includes a one-way valve I3, a front brake accumulator 17 and an electro-hydraulic proportional brake valve I10 connected in series, and the rear brake oil circuit includes a one-way valve II4, a rear brake accumulator 16 and an electro-hydraulic proportional brake valve II15 connected in series; It also includes a pedal valve 9, the two oil inlet ends of the pedal valve 9 are respectively connected to the oil inlet ends of the electro-hydraulic proportional brake valve I10 and the electro-hydraulic proportional brake valve II15, the two oil outlet ends of the pedal valve 9 are respectively connected to the oil outlet ends of the electro-hydraulic proportional brake valve I10 and the electro-hydraulic proportional brake valve II15 through a shuttle valve II11 and a shuttle valve III14, the oil outlet end of the shuttle valve II11 is connected to the front wheel brake 12, and the oil outlet end of the shuttle valve III14 is connected to the rear wheel brake 13; The hydraulically controlled end of the pedal valve 9 is connected to a hydraulically controlled pilot valve 8, and the oil inlet end of the hydraulically controlled pilot valve 8 is connected to the front brake accumulator 17 and the rear brake accumulator 16 through a shuttle valve Ⅰ7. The hydraulically controlled end of the hydraulically controlled pilot valve 8 is connected to an electromagnetic reversing valve 6, and the oil inlet end of the electromagnetic reversing valve 6 is connected to a hydraulically controlled reversing valve 5. The hydraulically controlled reversing valve 5 is provided with two oil inlet ends, and the two oil inlet ends of the hydraulically controlled reversing valve 5 are respectively connected to the oil outlet ends of the one-way valve Ⅰ3 and the one-way valve Ⅱ4, and the hydraulically controlled end of the hydraulically controlled reversing valve 5 is connected to the oil inlet end on the same side.

2. The unmanned emergency hydraulic brake system for a mine car as claimed in claim 1, characterized in that: The pedal valve 9 is provided with two groups of linked valve bodies, and the working position structures of the two groups of valve bodies are the same. The two oil inlet ends of the pedal valve 9 are respectively connected to the oil inlet ends of the two groups of valve bodies, and the two oil outlet ends of the pedal valve 9 are respectively the oil outlet ends of the two groups of valve bodies.

3. The unmanned emergency hydraulic brake system for a mine car as claimed in claim 1, characterized in that: When there is no hydraulic oil at the hydraulic control end of the pedal valve 9, the oil inlet and oil outlet of the pedal valve 9 are not connected. When there is hydraulic oil at the hydraulic control end of the pedal valve 9, the oil inlet and oil outlet of the pedal valve 9 are connected.

4. The unmanned emergency hydraulic brake system for a mine car as claimed in claim 1, characterized in that: The hydraulically controlled pilot valve 8 is a two-position three-way hydraulically controlled valve. When the hydraulically controlled pilot valve 8 is in the non-hydraulic controlled position, the oil inlet end of the hydraulically controlled pilot valve 8 is connected to the hydraulically controlled end of the pedal valve 9. When the hydraulically controlled pilot valve 8 is in the hydraulically controlled position, the hydraulically controlled end of the pedal valve 9 is connected to the oil tank 1.

5. The unmanned emergency hydraulic brake system for a mine car as claimed in claim 1, characterized in that: The preset pressure of the hydraulically controlled pilot valve 8 is the same as the system setting value.

6. The unmanned emergency hydraulic brake system for a mine car as claimed in claim 4, characterized in that: The electromagnetic reversing valve 6 is a two-position three-way electromagnetic reversing valve. When the electromagnetic reversing valve 6 is in an electric potential-passing state, the hydraulic control end of the hydraulic control pilot valve 8 is connected to the oil outlet end of the hydraulic control reversing valve 5. When the electromagnetic reversing valve 6 is in an electric potential-free state, the hydraulic control end of the hydraulic control pilot valve 8 is connected to the oil tank 1.

7. The unmanned emergency hydraulic brake system for a mine car as claimed in claim 1, characterized in that: The hydraulically controlled reversing valve 5 is a three-position, three-way, double hydraulically controlled reversing valve. The middle position of the hydraulically controlled reversing valve 5 is a two-way position. When the pressure at the left oil inlet end of the hydraulically controlled reversing valve 5 is higher and the hydraulically controlled reversing valve 5 works in the left position, the output end of the hydraulically controlled reversing valve 5 is connected to the right oil inlet end.

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