A snow plow rolling brush rotating speed control hydraulic system

Abstract

The utility model discloses a snow removal vehicle roll brush rotation speed control hydraulic system, including oil tank (1) and roll brush motor (4), be equipped with gear pump (2) and oil return filter (5) between oil tank (1) and roll brush motor (4), gear pump (2) sets up on the oil inlet, oil return filter (5) sets up on the oil return, roll brush motor (4) is connected with gear pump (2) and oil return filter (5) link to each other and is used for controlling roll brush motor (4) start -stop's threaded cartridge valve group (3), roll brush motor (4) is connected with threaded cartridge valve group (3) in parallel, use threaded cartridge valve group (3) to realize roll brush motor (4) start -stop control, safe pressure protection, roll brush rotation speed regulation function, and use gear pump (2) to replace variable plunger pump and reduce cost, and gear pump (2) to oil cleanliness requirement is not plunger pump high, has reduced the maintenance cost of oil.

Description

Technical Field

[0001] This utility model belongs to the field of snowplow technology. Specifically, this utility model relates to a hydraulic system for controlling the rotation speed of a snowplow brush. Background Technology

[0002] There are two main schemes for the existing hydraulic system for controlling the speed of snowplow brushes: one is to use an open variable displacement piston pump and a cover plate cartridge valve for control; the other is to use a closed variable displacement piston pump for control.

[0003] A patent application with patent number 201922302056.3, published on July 17, 2020, discloses a hydraulic system for a snowplow, including a hydraulic tank, a driver, a hydraulic pump, a pressure reducing valve, a solenoid valve, a solenoid directional valve, and a cylinder. The hydraulic pump is connected to the hydraulic tank, and the hydraulic pump is connected to the pressure reducing valve via an inlet pipe. The pressure reducing valve is connected to the solenoid valve, and the solenoid valve is connected to the rodless chamber of the cylinder. The inlet pipe is connected to the pressure port P of the solenoid directional valve, the working port A of the solenoid directional valve is connected to the rod chamber of the cylinder, the working port B of the solenoid directional valve is connected to the rodless chamber of the cylinder, and the return port T of the solenoid directional valve is connected to the hydraulic tank via a return pipe. This invention equips the hydraulic cylinder with a pressure reducing valve that has a reverse overflow function. It automatically pumps in hydraulic oil when the oil pressure in the rodless chamber of the hydraulic cylinder decreases and releases hydraulic oil when the oil pressure in the rodless chamber of the hydraulic cylinder increases, thereby stabilizing the pressure in the rodless chamber of the hydraulic cylinder and ensuring that the snowplow's roller brush or auger can maintain synchronous following and stable adhesion even when facing undulating ground.

[0004] In existing technologies, whether using an open variable displacement piston pump, a cover plate cartridge valve, or a closed variable displacement piston pump, the installation cost and subsequent maintenance cost are too high. Utility Model Content

[0005] The present invention aims to provide a hydraulic system for controlling the rotational speed of snowplow brushes that can reduce costs.

[0006] To achieve the above objectives, the technical solution adopted by this utility model is as follows: a hydraulic system for controlling the rotation speed of a snowplow brush, comprising an oil tank and a brush motor, wherein a gear pump and a return oil filter are provided between the oil tank and the brush motor, the gear pump is provided on the oil inlet line, the return oil filter is provided on the oil return line, and the brush motor is connected to a threaded cartridge valve assembly connected to the gear pump and the return oil filter and used to control the start and stop of the brush motor, wherein the brush motor and the threaded cartridge valve assembly are connected in parallel.

[0007] The threaded cartridge valve assembly includes an unloading pilot valve connected to the gear pump, and a damping plug is provided between the unloading pilot valve and the gear pump.

[0008] The gear pump is connected to an unloading main valve in parallel with the unloading pilot valve.

[0009] A logic switching valve is provided between the gear pump and the roller brush motor, in parallel with the unloading main valve and the unloading pilot valve, and the logic switching valve is connected in series with the gear pump and the roller brush motor.

[0010] The unloading pilot valve and the unloading main valve are signal connected.

[0011] The threaded cartridge valve assembly also includes a bypass speed control valve connected in parallel with the roller brush motor.

[0012] The damping plug is connected to a safety valve in parallel with the unloading pilot valve.

[0013] The technical advantages of this utility model are as follows: the use of a threaded cartridge valve group realizes the functions of starting and stopping the roller brush motor, safety pressure protection, and roller brush speed adjustment, thereby replacing the cover plate cartridge valve, making the valve group structure more compact, saving installation costs, and using a gear pump instead of a variable piston pump reduces costs. In addition, the gear pump does not have as high requirements for oil cleanliness as the piston pump, thus reducing the maintenance costs of the oil. Attached Figure Description

[0014] This instruction manual includes the following figures. Appendix Figure 1 This is a structural diagram of a hydraulic system for controlling the rotational speed of a snowplow brush. The contents shown are as follows: The following are labeled in the diagram: 1. Oil tank; 2. Gear pump; 3. Threaded cartridge valve assembly; 4. Roller brush motor; 5. Return oil filter; 3.1. Check valve; 3.2. Unloading pilot valve; 3.3. Safety valve; 3.4. Unloading main valve; 3.5. Logic switch valve; 3.6. Bypass speed control valve; 3.7. Damping plug. Detailed Implementation

[0015] The specific embodiments of this utility model will be further described in detail below with reference to the accompanying drawings, in order to help those skilled in the art to have a more complete, accurate and in-depth understanding of the utility model concept and technical solution, and to facilitate its implementation.

[0016] Please see Figure 1A hydraulic system for controlling the speed of a snowplow brush includes an oil tank 1 and a brush motor 4. A gear pump 2 and a return oil filter 5 are provided between the oil tank 1 and the brush motor 4. The gear pump 2 is located on the oil inlet line, and the return oil filter 5 is located on the oil return line. The brush motor 4 is connected to a threaded cartridge valve assembly 3, which is connected to the gear pump 2 and the return oil filter 5 and is used to control the start and stop of the brush motor 4. The brush motor 4 and the threaded cartridge valve assembly 3 are connected in parallel. The threaded cartridge valve assembly 3 is used to realize the start and stop control of the brush motor 4, safety pressure protection, and brush speed adjustment functions. The gear pump 2 is used instead of a variable displacement piston pump to reduce costs. Furthermore, the gear pump 2 does not have as high requirements for oil cleanliness as the piston pump, thus reducing the maintenance costs of the oil.

[0017] The threaded cartridge valve assembly 3 includes an unloading pilot valve 3.2 connected to the gear pump 2. A damping plug 3.7 is provided between the unloading pilot valve 3.2 and the gear pump 2. When the unloading pilot valve 3.2 is energized, there is no pressure difference across the damping plug 3.7, and the hydraulic oil will not pass through the damping plug 3.7. The hydraulic oil enters the brush motor 4 normally and is used normally. However, when the unloading pilot valve 3.2 is de-energized, a pressure difference is established across the damping plug 3.7, which prevents the hydraulic oil from smoothly entering the brush motor 4. The hydraulic oil returns directly to the oil tank 1 through the threaded cartridge valve assembly 3 and the return oil filter 5, completing the empty circulation unloading function of the pressure oil of the gear pump 2, and the brush motor 4 stops working.

[0018] Gear pump 2 is connected to unloading main valve 3.4 in parallel with unloading pilot valve 3.2; when unloading pilot valve 3.2 is de-energized, unloading pilot valve 3.2 operates in the upper position, and a pressure difference is established before and after damping plug 3.7, causing unloading main valve 3.4 to operate in the upper position. The hydraulic oil passes through the upper position of unloading main valve 3.4 and finally returns to oil tank 1 through return oil filter 5.

[0019] A logic switch valve 3.5 is provided between the gear pump 2 and the roller brush motor 4, which is connected in parallel with the unloading main valve 3.4 and the unloading pilot valve 3.2. The logic switch valve 3.5 is connected in series with the gear pump 2 and the roller brush motor 4. When the hydraulic oil pressure is sufficient, the hydraulic oil can open the logic switch valve 3.5 and enter the roller brush motor 4. The logic switch valve 3.5 is used to control whether the hydraulic oil can enter the roller brush motor 4.

[0020] The unloading pilot valve 3.2 and the unloading main valve 3.4 are connected by signal.

[0021] The threaded cartridge valve assembly 3 also includes a bypass speed control valve 3.6 connected in parallel with the roller brush motor 4. The speed of the roller brush motor 4 is adjusted by the bypass speed control valve 3.6. The greater the current through the bypass speed control valve 3.6, the smaller the return oil flow through the bypass speed control valve 3.6, the greater the flow of pressurized oil into the roller brush motor 4, and the higher the speed of the roller brush motor 4. Conversely, the smaller the current through the bypass speed control valve 3.6, the larger the return oil flow through the bypass speed control valve 3.6, the smaller the flow into the roller brush motor 4, and the lower the speed of the roller brush motor 4.

[0022] The damping plug 3.7 is connected to a safety valve 3.3 in parallel with the unloading pilot valve 3.2. When the load on the roller brush increases abnormally, causing the working pressure to exceed the set pressure of the safety valve 3.3 in the threaded cartridge valve group 3, the safety valve 3.3 opens, and the pilot oil returns to the oil tank 1 through the safety valve 3.3. Therefore, a pressure difference is established before and after the damping plug 3.7, which enables the unloading main valve 3.4 to work in the upper position to achieve the overflow function, preventing the pressure from further increasing and damaging the hydraulic components and causing the pipe to burst.

[0023] 4-way start / stop control for the roller brush motor: After starting gear pump 2, when the electromagnet DT1 of unloading pilot valve 3.2 in threaded cartridge valve group 3 is energized, unloading pilot valve 3.2 operates in the lower position, preventing the pilot oil circuit from returning oil and thus preventing the establishment of a pressure difference before and after damping plug 3.7. This causes unloading main valve 3.4 to operate in the lower position, and gear pump 2's suction port draws oil from oil tank 1. Gear pump 2's pressure port is connected to the P port of threaded cartridge valve group 3. The pressure oil at the P port passes through the left position of logic switch valve 3.5 and then through the A port of threaded cartridge valve group 3 to enter the oil inlet C of roller brush motor 4, driving roller brush motor 4 to work. The oil at the return port D of roller brush motor 4 passes through the B port of threaded cartridge valve group 3 to the T port, passes through the return oil filter 5, and then returns to oil tank 1, completing the working cycle. After gear pump 2 is started, when the solenoid DT1 of the unloading pilot valve 3.2 in the threaded cartridge valve assembly 3 is de-energized, the unloading pilot valve 3.2 operates in its upper position. The pilot oil circuit passes through the damping plug 3.7, the upper position of the unloading pilot valve 3.2, the T port of the threaded cartridge valve assembly 3, and the return oil filter 5 back to the oil tank 1. A pressure difference is established before and after the damping plug 3.7, causing the unloading main valve 3.4 to operate in its upper position. The oil suction port of gear pump 2 draws oil from the oil tank 1, and the oil pressure port of gear pump 2 is connected to the P port of the threaded cartridge valve assembly 3. The pressurized oil at the P port passes through the unloading main valve. The upper part of 3.4 goes directly to the return oil filter 5 through the T port of the threaded cartridge valve group 3 and then back to the oil tank 1. At the same time, due to the function of the logic switch valve 3.5 in the threaded cartridge valve group 3, the pressure oil of the gear pump 2 cannot open the logic switch valve 3.5 to enter the oil inlet C of the roller brush motor 4, thus completing the empty circulation unloading function of the pressure oil of the gear pump 2. The roller brush motor 4 stops working. In order to prevent the roller brush motor 4 from sucking in the oil inlet C of the roller brush motor 4 due to rotational inertia at the moment of stopping, a one-way valve 3.1 for replenishing oil is set in the threaded cartridge valve group 3.

[0024] Safety pressure protection: During the operation of the roller brush motor 4, when the roller brush load increases abnormally, causing the working pressure to exceed the set pressure of the safety valve 3.3 in the threaded cartridge valve assembly 3, the safety valve 3.3 opens. The pilot oil circuit returns to the oil tank 1 through the damping plug 3.7, the safety valve 3.3, the T port of the threaded cartridge valve assembly 3, and the return oil filter 5. A pressure difference is established before and after the damping plug 3.7, causing the unloading main valve 3.4 to operate in the upper position. The oil suction port of the gear pump 2 draws oil from the oil tank 1. The oil pressure port of the gear pump 2 is connected to the P port of the threaded cartridge valve assembly 3. The pressurized oil at the P port passes through the upper position of the unloading main valve 3.4 and directly through the T port of the threaded cartridge valve assembly 3 to the return oil filter 5 and then back to the oil tank 1, preventing the pressure from further increasing and damaging the hydraulic components and the risk of pipe rupture.

[0025] Brush speed adjustment: After starting gear pump 2, the solenoid DT1 of unloading pilot valve 3.2 in threaded cartridge valve assembly 3 is energized, and unloading pilot valve 3.2 operates in the lower position, preventing the return of pilot oil and thus preventing the establishment of a pressure difference before and after damping plug 3.7. This causes unloading main valve 3.4 to operate in the lower position, and gear pump 2's suction port draws oil from oil tank 1. Gear pump 2's pressure port is connected to port P of threaded cartridge valve assembly 3. The pressure oil at port P is split into two paths after passing through the left position of logic switch valve 3.5. One path enters the oil inlet C of roller brush motor 4 through port A of threaded cartridge valve assembly 3, and the other path returns to port T through bypass speed control valve 3.6 in threaded cartridge valve assembly 3, then back to return oil filter 5 and then back to the original position. The speed of the roller brush motor 4 is adjusted by controlling the current of the proportional electromagnet DT2 in the bypass speed control valve 3.6. When the current of the proportional electromagnet DT2 in the bypass speed control valve 3.6 is large, the flow rate of the pressurized oil from the gear pump 2 into the inlet C of the roller brush motor 4 is large, and the flow rate back to the oil tank 1 through the bypass speed control valve 3.6 is small, resulting in a higher speed for the roller brush motor 4. Conversely, when the current of the proportional electromagnet DT2 in the bypass speed control valve 3.6 is small, the flow rate of the pressurized oil from the gear pump 2 into the inlet C of the roller brush motor 4 is small, and the flow rate back to the oil tank 1 through the bypass speed control valve 3.6 is large, resulting in a lower speed for the roller brush motor 4.

[0026] The technical advantages of this utility model are as follows: the use of threaded cartridge valve group 3 realizes the start and stop control of the roller brush motor 4, safety pressure protection, and roller brush speed adjustment functions, thereby replacing the cover plate cartridge valve, making the valve group structure more compact and saving installation costs. In addition, the use of gear pump 2 to replace variable plunger pump reduces costs, and gear pump 2 has lower requirements for oil cleanliness than plunger pump, thus reducing the maintenance costs of oil.

[0027] The present invention has been described above by way of example with reference to the accompanying drawings. Obviously, the specific implementation of the present invention is not limited to the above-described manner. Any non-substantial improvements made using the inventive concept and technical solution of the present invention; or the direct application of the inventive concept and technical solution to other situations without modification, are all within the protection scope of the present invention.

Claims

1. A hydraulic system for controlling the rotation speed of a snowplow brush, comprising an oil tank (1) and a brush motor (4), characterized in that: A gear pump (2) and a return oil filter (5) are provided between the oil tank (1) and the roller brush motor (4). The gear pump (2) is located on the oil inlet line, and the return oil filter (5) is located on the oil return line. The roller brush motor (4) is connected to a threaded cartridge valve assembly (3) which is connected to the gear pump (2) and the return oil filter (5) and is used to control the start and stop of the roller brush motor (4). The roller brush motor (4) and the threaded cartridge valve assembly (3) are connected in parallel.

2. The hydraulic system for controlling the rotation speed of a snowplow brush according to claim 1, characterized in that: The threaded cartridge valve assembly (3) includes an unloading pilot valve (3.2) connected to the gear pump (2), and a damping plug (3.7) is provided between the unloading pilot valve (3.2) and the gear pump (2).

3. The hydraulic system for controlling the rotation speed of a snowplow brush according to claim 2, characterized in that: The gear pump (2) is connected to an unloading main valve (3.4) in parallel with the unloading pilot valve (3.2).

4. The hydraulic system for controlling the rotation speed of a snowplow brush according to claim 3, characterized in that: A logic switching valve (3.5) is provided between the gear pump (2) and the roller brush motor (4) in parallel with the unloading main valve (3.4) and the unloading pilot valve (3.2). The logic switching valve (3.5) is connected in series with the gear pump (2) and the roller brush motor (4).

5. The hydraulic system for controlling the rotation speed of a snowplow brush according to claim 3, characterized in that: The unloading pilot valve (3.2) and the unloading main valve (3.4) are signal connected.

6. The hydraulic system for controlling the rotation speed of a snowplow brush according to claim 2, characterized in that: The threaded cartridge valve assembly (3) also includes a bypass speed control valve (3.6) connected in parallel with the brush motor (4).

7. The hydraulic system for controlling the rotation speed of a snowplow brush according to claim 2, characterized in that: The damping plug (3.7) is connected to a safety valve (3.3) in parallel with the unloading pilot valve (3.2).

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