Single-shot sweeper hydraulic braking auxiliary system and control method thereof

Abstract

The application discloses a single-shot cleaning vehicle hydraulic braking auxiliary system and a control method thereof, and the system comprises a walking pump, an auxiliary braking valve, a walking hydraulic motor and a vehicle-mounted controller. The walking pump comprises a first oil inlet, a second oil inlet, a third oil inlet for oil supplement and a fourth oil outlet for oil discharge. The walking hydraulic motor comprises a first oil inlet / outlet connected with the first oil inlet and a second oil inlet / outlet connected with the second oil inlet. The auxiliary braking valve comprises a first working oil inlet connected with the first oil inlet, a second working oil inlet connected with the second oil inlet, an oil inlet connected with the third oil inlet and an oil outlet connected with the fourth oil outlet. The vehicle-mounted controller is connected with the walking pump and the auxiliary braking valve. The application solves the problem that the engine is shut down due to emergency braking during static hydraulic walking, reduces the braking impact, shortens the braking distance and the braking time and improves the reliability.

Description

Technical Field

[0001] This invention relates to a hydraulic braking auxiliary system and control method for a single-engine sweeper, belonging to the technical field of road sweeper technology. Background Technology

[0002] Currently, single-engine sweepers use a hydrostatic system to drive the entire vehicle, and the brakes generally use automatic chassis brakes. When braking in hydraulic mode, the system needs time to unload, which may cause the engine to stall during emergency braking. If the vehicle is on a slope, this may cause a safety hazard of rolling away. Summary of the Invention

[0003] The purpose of this invention is to overcome the shortcomings of the prior art and provide a hydraulic braking auxiliary system and control method for a single-engine sweeper, which solves the problem of engine stalling during emergency braking when traveling on hydrostatic pumps, while reducing braking impact, shortening braking distance, reducing braking time, and improving reliability.

[0004] To achieve the above objectives, the present invention is implemented using the following technical solution:

[0005] In a first aspect, the present invention provides a hydraulic braking auxiliary system for a single-engine sweeper, comprising: a travel pump, an auxiliary brake valve, a travel hydraulic motor, and an on-board controller;

[0006] The traveling pump includes a first oil port for inlet / outlet, a second oil port, a third oil port for replenishing oil, and a fourth oil port for draining oil.

[0007] The walking hydraulic motor includes a first inlet / outlet oil port connected to a first oil port and a second inlet / outlet oil port connected to a second oil port;

[0008] The auxiliary brake valve includes a first working port connected to a first oil port, a second working port connected to a second oil port, an oil inlet connected to a third oil port, and an oil drain port connected to a fourth oil port.

[0009] The vehicle controller is connected to the travel pump and the auxiliary brake valve.

[0010] Furthermore, the auxiliary braking valve includes an electromagnetic directional valve, which is connected to the vehicle controller.

[0011] Furthermore, the system also includes a transfer case, on which the travel pump and travel hydraulic motor are mounted, and power is output or input to each component through the transfer case.

[0012] Furthermore, the travel pump is a variable displacement pump, including a replenishing pump, a replenishing check valve, an overflow valve, a safety valve, a filter, and a variable displacement control valve. The replenishing pump, replenishing check valve, overflow valve, safety valve, filter, and variable displacement control valve are integrated, and the displacement of the travel pump is indirectly controlled by the vehicle controller signal.

[0013] Furthermore, the replenishing pump is integrated in series with the traveling pump, and the replenishing pump includes a fifth oil port for oil inlet and a sixth oil port for oil outlet.

[0014] Furthermore, the auxiliary braking valve also includes a hydraulically controlled directional valve, which is connected to the replenishing pump.

[0015] Furthermore, the walking hydraulic motor also includes: a control port connected to the sixth port of the replenishing pump, a seventh port connected to the oil tank, and an eighth port connected to the auxiliary brake valve.

[0016] Furthermore, the oil inlet of the auxiliary brake valve is connected to the sixth oil port of the replenishing pump, the first working oil port of the auxiliary brake valve is also connected to the second inlet / outlet oil port of the travel hydraulic motor, and the second working oil port of the auxiliary brake valve is also connected to the first inlet / outlet oil port of the travel hydraulic motor.

[0017] Furthermore, the auxiliary brake valve is also connected to the parking signal.

[0018] In a second aspect, the present invention provides a control method for a hydraulic braking assist system of a single-engine sweeper according to any one of the foregoing claims, comprising:

[0019] During hydraulic driving, the on-board controller reads different tilt angles of the brake pedal, outputs corresponding current values, and controls the displacement of the walking pump to decrease by a fixed value 'a', thereby reducing the vehicle's driving speed.

[0020] When the vehicle controller reads that the monitored braking signal is greater than the set value, it outputs the corresponding current value to control the displacement of the travel pump to decrease by a fixed value b.

[0021] At the same time, the vehicle controller outputs another signal to the solenoid reversing valve on the auxiliary brake valve, so that the first oil port and the second oil port on the travel pump are switched to connect with the first inlet / outlet oil port of the travel hydraulic motor.

[0022] At this point, the load in the travel pump decreases rapidly, and the power transmission between the travel pump and the travel hydraulic motor is interrupted. The reaction force generated by braking cannot be transmitted to the engine through the travel pump, causing the engine to shut down.

[0023] Compared with the prior art, the beneficial effects achieved by the present invention are as follows:

[0024] This invention provides a hydraulic braking auxiliary system and control method for a single-engine sweeper, which effectively solves the problems of impact and stalling during braking of hydrostatically driven sweepers, and improves reliability. Attached Figure Description

[0025] Figure 1 This is a hydraulic circuit diagram of a hydraulic braking auxiliary system for a single-engine sweeper provided in an embodiment of the present invention;

[0026] Figure 2 This is a schematic diagram of the oil circuit of the auxiliary braking valve provided in an embodiment of the present invention.

[0027] In the diagram: 1. Transfer case; 2. Travel pump; 3. Auxiliary brake valve; 4. Make-up pump; 5. Travel hydraulic motor; 6. Hydraulic directional valve; 7. Solenoid directional valve. Detailed Implementation

[0028] The present invention will be further described below with reference to the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present invention, and should not be used to limit the scope of protection of the present invention.

[0029] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined with "first," "second," etc., may explicitly or implicitly include one or more of that feature. In the description of this invention, unless otherwise stated, "a plurality of" means two or more.

[0030] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art will understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0031] Example 1

[0032] See attached document Figure 1This embodiment describes a hydraulic braking auxiliary system for a single-engine sweeper, including: a transfer case 1, a travel pump 2, an auxiliary brake valve 3, a replenishing pump 4, and a travel hydraulic motor 5. The travel pump 2 and the travel hydraulic motor 5 are mounted on the transfer case 1, and the transfer case 1 provides power to each component.

[0033] See attached document Figure 1 The travel pump 2 includes a first oil port for oil inlet / outlet, a second oil port, a third oil port for oil replenishment, and a fourth oil port connected to the oil tank. The replenishing oil pump 4 is integrated in series with the travel pump 2, and includes a fifth oil port for oil inlet and a sixth oil port for oil outlet. The travel hydraulic motor 5 includes a first oil inlet / outlet connected to the first oil port of the travel pump 2, a second oil inlet / outlet connected to the second oil port of the travel pump 2, a control oil port connected to the sixth oil port of the replenishing oil pump 4, a seventh oil port connected to the oil tank, and an eighth oil port connected to the auxiliary brake valve 3. The travel pump 2 is a variable displacement pump, including the replenishing oil pump 4, a replenishing check valve, an overflow valve, a safety valve, a filter, and a variable displacement control valve. The variable displacement pump is integrated in series with the replenishing oil pump 4, and the replenishing oil pump 4, the replenishing check valve, the overflow valve, the safety valve, the filter, and the variable displacement control valve are integrated. The displacement of the variable displacement pump is indirectly controlled by the vehicle controller signal.

[0034] See attached document Figure 2 The auxiliary brake valve 3 includes an electromagnetic directional valve 7, a hydraulic directional valve 6, a drain port, an inlet port, a first working port, and a second working port. The drain port of the auxiliary brake valve 3 is connected to the fourth port of the travel pump 2, the inlet port of the auxiliary brake valve 3 is connected to the sixth port of the replenishing pump 4, the first working port of the auxiliary brake valve 3 is connected to the first port of the travel pump 2 and the second inlet / outlet port of the travel hydraulic motor 5, and the second working port of the auxiliary brake valve 3 is connected to the second port of the travel pump 2 and the first inlet / outlet port of the travel hydraulic motor 5. The auxiliary brake valve 3 can be arranged independently or integrated into the travel pump 2, but is not limited to these two forms.

[0035] In this embodiment, the electromagnetic reversing valve 7 in the travel pump 2 and the auxiliary brake valve 3 is connected to the vehicle controller, which is connected to the brake signal line of the chassis. During braking, the vehicle controller reads the brake pedal tilt angle of the chassis. During hydraulic travel, the vehicle controller reads different brake pedal tilt angles and outputs corresponding current values ​​to control the displacement of the travel pump 2 to decrease by a fixed value a, thereby reducing the vehicle speed. When the vehicle controller reads that the monitored braking signal is greater than the set value, it outputs the corresponding current value to control the displacement of the travel pump 2 to decrease by a fixed value b. At the same time, the vehicle controller outputs another signal to the electromagnetic reversing valve 7 on the auxiliary brake valve 3, causing the first oil port and the second oil port on the travel pump 2 to switch to connect with the first inlet / outlet oil port of the travel hydraulic motor 5. At this time, the load in the travel pump 2 will be rapidly reduced, and the power transmission between the travel pump 2 and the travel hydraulic motor 5 will be interrupted. The reaction force generated by braking cannot be transmitted to the engine through the travel pump 2, causing the engine to shut down.

[0036] In this embodiment, two variable methods are simultaneously performed: changing the engine speed by altering the accelerator pedal to control the variable pump to change the vehicle speed, and changing the vehicle speed by reading the brake pedal signal from the vehicle controller. These methods do not affect each other.

[0037] In this embodiment, the switching time of the hydraulic directional valve 6 in the auxiliary brake valve 3 can be controlled by controlling the pressure of the replenishing pump 4, thereby adjusting the impact during braking and improving comfort.

[0038] In this embodiment, the auxiliary brake valve 3 is also connected to the parking signal, and it also functions during parking operations or temporary stops to prevent misoperation.

[0039] Example 2

[0040] This embodiment provides a control method for the hydraulic braking assist system of a single-engine sweeper according to any one of Embodiment 1, including:

[0041] During hydraulic driving, the vehicle controller reads different tilt angles of the brake pedal, outputs corresponding current values, and controls the displacement of the walking pump 2 to decrease by a fixed value a, thereby reducing the vehicle's driving speed.

[0042] When the vehicle controller reads that the monitored braking signal is greater than the set value, it outputs the corresponding current value to control the displacement of the travel pump 2 to decrease by a fixed value b.

[0043] At the same time, the vehicle controller outputs another signal to the electromagnetic reversing valve 7 on the auxiliary brake valve 3, so that the first oil port and the second oil port on the travel pump 2 are switched to connect with the first inlet / outlet oil port of the travel hydraulic motor 5.

[0044] At this time, the load in the travel pump 2 decreases rapidly, and the power transmission between the travel pump 2 and the travel hydraulic motor 5 is interrupted. The reaction force generated by braking cannot be transmitted to the engine through the travel pump 2, causing the engine to shut down.

[0045] The above specific embodiments have provided a detailed description of the principles and implementation methods of the present invention. These embodiments are provided to aid in understanding the method and core ideas of the present invention. Inventions that achieve equivalent effects by changing the pump control method or the hydraulic motor control method all fall within the protection scope of the claims of the present invention. Furthermore, it should be noted that those skilled in the art can make various improvements and modifications to the present invention without departing from its principles, and these improvements and modifications also fall within the scope of the claims of the present invention.

[0046] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A hydraulic braking auxiliary system for a single-engine sweeper, characterized in that, include: Walking pump (2), auxiliary brake valve (3), walking hydraulic motor (5), vehicle controller; The traveling pump (2) includes a first oil port for inlet / outlet, a second oil port, a third oil port for replenishing oil, and a fourth oil port for draining oil; The walking hydraulic motor (5) includes a first inlet / outlet oil port connected to the first oil port and a second inlet / outlet oil port connected to the second oil port; The auxiliary brake valve (3) includes a first working port connected to the first oil port, a second working port connected to the second oil port, an oil inlet connected to the third oil port, and an oil outlet connected to the fourth oil port. The vehicle controller is connected to the walking pump (2) and the auxiliary brake valve (3); The auxiliary braking valve (3) includes an electromagnetic reversing valve (7), which is connected to the vehicle controller; The auxiliary braking valve (3) also includes a hydraulically controlled directional valve (6), which is connected to the oil replenishment pump (4); The oil inlet of the auxiliary brake valve (3) is connected to the sixth oil port of the oil replenishment pump (4). The first working oil port of the auxiliary brake valve (3) is also connected to the second inlet / outlet oil port of the walking hydraulic motor (5). The second working oil port of the auxiliary brake valve (3) is also connected to the first inlet / outlet oil port of the walking hydraulic motor (5).

2. The hydraulic braking assist system for a single-engine sweeper according to claim 1, characterized in that, The system also includes a transfer case (1), on which the travel pump (2) and travel hydraulic motor (5) are mounted, and power is output or input to each component through the transfer case (1).

3. The hydraulic braking assist system for a single-engine sweeper according to claim 1, characterized in that, The travel pump (2) is a variable pump, including a replenishment pump (4), a replenishment check valve, an overflow valve, a safety valve, a filter, and a variable control valve. The replenishment pump (4), the replenishment check valve, the overflow valve, the safety valve, the filter, and the variable control valve are integrated, and the displacement of the travel pump (2) is indirectly controlled by the vehicle controller signal.

4. The hydraulic braking assist system for a single-engine sweeper according to claim 3, characterized in that, The replenishing pump (4) is integrated in series with the traveling pump (2). The replenishing pump (4) includes a fifth oil port for oil inlet and a sixth oil port for oil outlet.

5. The hydraulic braking assist system for a single-engine sweeper according to claim 4, characterized in that, The walking hydraulic motor (5) also includes: a control port connected to the sixth port of the oil replenishment pump (4), a seventh port connected to the oil tank, and an eighth port connected to the auxiliary brake valve (3).

6. The hydraulic braking assist system for a single-engine sweeper according to claim 1, characterized in that, The auxiliary brake valve (3) is also connected to the parking signal.

7. A control method for the hydraulic braking auxiliary system of a single-engine sweeper according to claim 1, characterized in that, include: During hydraulic driving, the vehicle controller reads different tilt angles of the brake pedal, outputs corresponding current values, and controls the displacement of the walking pump (2) to decrease by a fixed value a, thereby reducing the vehicle's driving speed. When the vehicle controller reads that the monitored braking signal is greater than the set value, it outputs the corresponding current value to control the displacement of the walking pump (2) to decrease by a fixed value b. At the same time, the vehicle controller outputs another signal to the electromagnetic reversing valve (7) on the auxiliary brake valve (3), so that the first oil port and the second oil port on the travel pump (2) are switched to connect with the first inlet / outlet oil port of the travel hydraulic motor (5); At this time, the load in the travel pump (2) decreases rapidly, and the power transmission between the travel pump (2) and the travel hydraulic motor (5) is interrupted. The reaction force generated by braking cannot be transmitted to the engine through the travel pump (2), causing the engine to shut down.

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