CN205064458U - Loader fan drive hydraulic system - Google Patents

Abstract

The utility model discloses a fan-driven hydraulic system for a loader, which comprises a gear pump, a hydraulic oil tank, a radiator, a pressure compensation valve, an electric proportional reversing valve, a forward and reverse motor, an ECU control box, a temperature sensor, a one-way valve, Speed sensor and engine control box; the utility model uses the ECU control box to uniformly control the loader's independent heat dissipation system, and realizes the function of intelligent temperature control, that is, the fan speed is adjusted according to the temperature of each medium, and has no direct relationship with the engine speed. It has a good energy-saving effect; at the same time, it realizes the intelligent reverse function, which allows the radiator to dissipate heat better, prolongs the continuous working time of the loader, and improves work efficiency; adopts a unique three-position electric proportional reversing valve, which can realize The positive and negative switching of the fan has zero impact, which improves the service life of the components of the hydraulic system and the fan.

Description

Loader fan drive hydraulic system

technical field

The utility model relates to a loader fan drive system, in particular to a loader fan drive hydraulic system.

Background technique

Due to the very bad working conditions of the loader, the dust in the air will block the radiator after working for a period of time, so the fan needs to be reversed to blow off the dust blocked on the radiator, so that the radiator can dissipate heat better. Currently, high-end The loader has begun to use the fan drive system with fan reverse function, but the current fan drive system uses a two-position four-way electromagnetic reversing valve to realize the fan reverse function. During the process of reversing, the solenoid valve is directly reversing, and the fan cannot be completely stopped during the reversing process, which has a large impact on the fan, reducing the service life of the fan, and the impact of the hydraulic system is also large, reducing the service life of the hydraulic parts .

Moreover, the speed of the existing fan is usually controlled according to the speed of the engine, that is, the higher the speed of the engine, the higher the speed of the fan, and it is not adjusted according to the actual temperature of the medium, which often causes unnecessary waste of energy.

Contents of the invention

Aiming at the problems existing in the above-mentioned prior art, the utility model provides a loader fan-driven hydraulic system, the fan speed is adjusted according to the temperature of each medium, realizing the function of intelligent temperature control, and the energy-saving effect is good; The rotation function allows the radiator to dissipate heat better, prolongs the continuous working time of the loader, and improves work efficiency; realizes zero-impact switching of the forward and reverse rotation of the fan, and improves the service life of each component of the hydraulic system and the fan.

In order to achieve the above purpose, the utility model is a loader fan drive hydraulic system, including a gear pump, a hydraulic oil tank, a radiator, a pressure compensation valve, an electric proportional reversing valve, a forward and reverse motor, an ECU control box, a temperature sensor, a single Directional valve, speed sensor and engine control box; the oil inlet of the gear pump is connected to the hydraulic oil tank, and the oil outlet is connected to the P port of the pressure compensation valve and the electric proportional directional valve respectively; the pressure compensation valve is connected to the inlet of the radiator, The outlet of the radiator is connected with the hydraulic oil tank; the T port of the electric proportional directional valve is connected with the inlet of the radiator; Port D is connected to the inlet of the check valve, and the oil outlets of the two check valves are connected to port a of the pressure compensation valve; port b of the pressure compensation valve is connected to the oil outlet of the gear pump; the ECU control box is connected to the electric proportional The reversing valve is connected, the temperature sensor is connected with the ECU control box, and is installed at the inlet of the radiator; the speed sensor is integrated on the forward and reverse motor and connected with the ECU control box, and the speed signal of the forward and reverse motor is collected in real time ; The ECU control box is connected with the engine control box to collect the speed signal of the engine in real time; the ECU control box is connected with a command reversal button.

Further, the utility model is provided with four temperature sensors, which are respectively used to collect temperature signals of coolant, hydraulic oil, torque converter oil, and intercooler air. The radiator is provided with four, and the four temperature sensors are respectively Mounted at the inlets of the four radiators.

Further in the utility model, a safety valve and a one-way valve are integrated in the forward and reverse motor; when the system pressure is higher than the pressure set by the safety valve, the safety valve is opened, and the oil flows directly from the safety valve through the one-way valve Back to tank. It can ensure that the forward and reverse motors work under normal working pressure and prolong their service life.

The utility model uses the ECU control box to uniformly control the independent heat dissipation system of the loader, and realizes the function of intelligent temperature control, that is, the fan speed is adjusted according to the temperature of each medium, which has no direct relationship with the engine speed, and has a good energy-saving effect; At the same time, the intelligent reverse function is realized. Due to the very bad working conditions of the loader, the dust in the air will block the radiator after working for a period of time, so the fan needs to be reversed to blow off the dust blocked on the radiator and let the heat dissipate. The better heat dissipation of the loader prolongs the continuous working time of the loader and improves the work efficiency; the system adopts a unique three-position electric proportional reversing valve, which can realize the zero impact of the forward and reverse switching of the fan, and improve the components of the hydraulic system and the fan. service life.

1) The electronic proportional directional valve is controlled by the ECU control box to realize the intelligent temperature control function of the independent heat dissipation of the loader, which reduces the power loss of the heat dissipation system and achieves a good energy-saving effect.

2) The electric proportional directional valve is controlled by the ECU control box to realize the intelligent reverse function of the independent heat dissipation of the loader, and three reverse modes can be realized. The reverse rotation of the fan has a very good automatic cleaning effect, which prolongs the continuous working time of the loader and improves the work efficiency.

3) The intelligent temperature control and reverse function are realized through a three-position electric proportional reversing valve, which can realize the zero-impact switching of the forward and reverse of the fan, and improve the service life of each component of the hydraulic system and the fan.

4) The bus control system is adopted, and all the above functions are uniformly controlled through an ECU control box, and the system layout is compact and beautiful.

5) Adopt an open control mode to support the secondary development of the control system, and users can expand or strengthen certain functions according to their needs.

Description of drawings

Fig. 1 is the schematic diagram of electro-hydraulic structure principle of the present utility model;

Figure 2 is a control flow chart of the fan speed intelligent temperature control function;

Figure 3 is a flow chart of fan intelligent reverse control.

In the figure: 1. gear pump, 2. hydraulic oil tank, 3. radiator, 4. pressure compensation valve, 5. electric proportional directional valve, 6. safety valve, 7. one-way valve, 8. forward and reverse motor, 9. ECU control box, 10. Temperature sensor, 11. Check valve, 12. Speed sensor, 13. Engine control box, 14. Instruction reverse button.

detailed description

In order to enable those skilled in the art to better understand the solution of the utility model, the utility model will be further described in detail below in conjunction with the accompanying drawings and specific embodiments.

As shown in Figure 1, the fan-driven hydraulic system of the loader of the present invention includes a gear pump 1, a hydraulic oil tank 2, a radiator 3, a pressure compensation valve 4, an electric proportional reversing valve 5, a forward and reverse motor 8, and an ECU control box 9. Temperature sensor 10, one-way valve 11, speed sensor 12 and engine control box 13; the oil inlet of the gear pump 1 is connected to the hydraulic oil tank 2, and the oil outlet is connected to the pressure compensation valve 4 and the electric proportional reversing valve 5 respectively The P port of the pressure compensation valve 4 is connected with the inlet of the radiator 3, and the outlet of the radiator 3 is connected with the hydraulic oil tank 2; the 5T port of the electric proportional reversing valve is connected with the inlet of the radiator 3, and the proportional reversing valve 5A, B The ports are respectively connected to the oil inlet and outlet ports of the forward and reverse motor 8, the ports of the proportional reversing valve 5C and D are connected to the inlet of the one-way valve 11, and the oil outlets of the two one-way valves 11 are connected to the port of the pressure compensation valve 4a; Port b of the compensation valve 4 is connected to the oil outlet of the gear pump 1, and the ECU control box 9 is connected to the electric proportional reversing valve 5, and the four are respectively used for collecting coolant, hydraulic oil, torque converter oil, and intercooler air The temperature sensor 10 of the temperature signal is connected with the ECU control box 9, and is loaded on the entrance of four radiators 3 respectively; Reverse the rotation speed signal of the motor 8; the ECU control box 9 is connected with the engine control box 13 to collect the rotation speed signal of the engine in real time; the ECU control box 9 is provided with an instruction reverse button 14 connected thereto.

Ports a and b of the pressure compensating valve 4 are respectively connected to the oil outlet of the gear pump 1 and the oil outlet of the electric proportional reversing valve 5 . When the spool of electric proportional reversing valve 5 is at the leftmost end, the pressure at port 5P of electric proportional reversing valve is equal to the pressure at port 4b of pressure compensation valve, because port A of electric proportional reversing valve 5 communicates with port C, port B and port D , so the pressure at port B is equal to the pressure at port 4a of the pressure compensating valve. Since the pressure at port 4b of the pressure compensating valve is equal to the pressure at port a plus the spring setting pressure, the pressure difference between the inlet and outlet ports of the electric proportional reversing valve 5 is a fixed value, which is The set pressure of the spring in the pressure compensation valve 4. In this case, it can be ensured that the flow rate of the hydraulic oil entering the forward and reverse motor 8 is directly proportional to the valve port opening of the electric proportional reversing valve 5 . That is, the larger the opening of the valve port, the larger the flow entering the forward and reverse motor 8, and the faster the fan speed; otherwise, the slower the fan speed. When the driver steps on the accelerator and the engine speed changes, the hydraulic oil flow output by the gear pump 1 will change, but since the pressure difference between the inlet and outlet of the electric proportional reversing valve 5 is constant, as long as the valve opening does not change, the system will The flow rate flowing to the forward and reverse motor 8 is constant, the fan speed does not change, and the excess hydraulic oil will directly flow back to the hydraulic oil tank 2 through the pressure compensating valve 4 . That is to say, the speed of the fan is not directly related to the speed of the engine.

In Figure 2, the four media of coolant, hydraulic oil, torque converter oil and cold air are respectively set to a temperature range, and within this temperature range, the fan speed increases according to the temperature rise. When the temperature of all media is lower than the minimum set value when the loader is just started, the current output by the ECU control box 9 makes the spool of the electric proportional reversing valve 5 in the left position, and the opening of the valve port is the smallest. At this time, the fan rotates forward at the lowest speed, and the air volume of the fan is the smallest, which is conducive to the rapid rise of the temperature of various media, increasing the heating speed and reducing the wear of the system; as the working time of the loader increases, the temperature of each medium gradually increases. When the temperature of any medium is higher than its minimum set value, the ECU control box 9 will gradually reduce the current output, the valve opening of the electric proportional reversing valve 5 will gradually increase, and the fan speed will gradually increase; When the temperature of any medium is higher than its maximum set value, the output current of the ECU control box 9 becomes 0 at this time, and the electric proportional reversing valve 5 moves to the leftmost end under the action of the spring. At this time, the opening of the valve port is the largest. The fan rotates at the highest speed, which is beneficial to the heat dissipation of the medium. In summary, the utility model utilizes the ECU control box to uniformly control the independent heat dissipation system of the loader, and realizes the function of intelligent temperature control, that is, the fan speed is adjusted according to the temperature of each medium, and has no direct relationship with the engine speed, which is very good. to the energy-saving effect;

On the basis of the above structure, the forward and reverse motor 8 is integrated with a safety valve 6 and a one-way valve 7; when the forward and reverse motor 8 rotates forward, the hydraulic oil enters the oil inlet of the motor through the P port of the electric proportional reversing valve 5 At this time, the fan rotates normally. When the system pressure is higher than the pressure set by the safety valve 6, the safety valve 6 opens, and the oil does not flow through the forward and reverse motor 8 and directly flows from the safety valve 6 to the one-way valve 7. Fuel tank, the reverse is the same. It can ensure that the forward and reverse motor 8 works under normal working pressure. Extend its service life.

In addition, the utility model also provides a method of using the above-mentioned loader fan to drive the hydraulic system to control the forward and reverse switching of the loader fan, as shown in Figure 3, including the following steps:

A. When the inversion condition is met, the ECU control box 9 gradually increases the output current, at this time, the valve opening of the electric proportional reversing valve 5 gradually decreases, and the fan speed gradually decreases;

B. When the current output by the ECU control box 9 makes the spool of the electric proportional reversing valve 5 in the neutral position, the oil inlet and outlet ports of the forward and reverse motor 8 are connected to the hydraulic oil tank 2, and the oil of the gear pump 1 passes through the pressure The compensation valve 4 returns to the oil tank, and the fan reduces the speed under the action of air resistance;

C. When the ECU control box 9 detects the signal of the speed sensor 12 on the forward and reverse motor 8, and the speed drops to 0, the ECU control box 9 will continue to increase the current output to the maximum. At this time, the spool of the electric proportional reversing valve 5 On the far right, the fan reverses at maximum speed;

D. When the reverse time reaches the set value, the ECU control box 9 gradually reduces the output current, and the fan speed gradually decreases. When the current output by the ECU control box 9 makes the spool of the electric proportional reversing valve in the neutral position, it is positive The oil inlet and outlet of the reversing motor 8 are connected to the hydraulic oil tank 2, the oil of the gear pump 1 returns to the oil tank through the pressure compensation valve 4, and the fan slowly reduces the speed under the action of air resistance;

E. When the ECU control box 9 detects the signal of the speed sensor 12 on the forward and reverse motor 8 and the speed drops to 0, the ECU control box 9 will continue to reduce the output current until the spool of the electric proportional reversing valve 5 can return to the left position, the fan rotates forward.

Through the above method and the unique three-position electric proportional reversing valve 5 of the utility model, the fan can realize zero impact when switching forward and reverse, which can protect the fan well and increase the service life of the fan and the system.

There are three kinds of reversal conditions in the above-mentioned step A, that is, the following three kinds of fan reversal modes are arranged: 1. Start the reverse rotation. When the ECU control box 9 detects that the engine speed is greater than 500r/min after the startup, the ECU control box 9 executes the reversal procedure. When the reverse rotation time reaches the set value, it will automatically resume forward rotation. When the power is turned on but the engine speed is lower than 500r/min, the fan will not reverse.

2. Command reversal, the ECU control box 9 of the utility model is provided with a command reversal button 14 connected to it, press the command reversal button 14, the ECU control box 9 executes the reversal procedure, and automatically recovers when the reversal time reaches the set value Forward. If the temperature of any medium in the coolant, hydraulic oil torque converter oil and cold air is higher than its maximum set value or the engine speed exceeds 1200r/min, the ECU control box 9 does not execute the reverse program.

3. The reversal condition is time reversal. During the normal operation of the loader, the ECU control box 9 will automatically execute a fan reversal procedure when the set time period is reached. If the temperature of any medium in the coolant, hydraulic oil, torque converter oil, and cold air is higher than its maximum setting value or the engine speed exceeds 1200r/min, the ECU control box 9 will not execute the reverse program until the next cycle, if If the reversal condition is met, the reversal will be carried out.

Certainly, the above-mentioned embodiments are only preferred solutions of the present invention, and are not limited thereto. On this basis, targeted adjustments can be made according to actual needs, so as to obtain different implementation modes. Since there are many ways of possible realization, it is not necessary to give examples one by one here.

Claims (3)

1. a loader fans drive hydraulic system, it is characterized in that, comprise gear pump (1), hydraulic oil container (2), radiator (3), pressure-compensated valve (4), electric proportional reversing valve (5), clockwise and anticlockwise motor (8), ECU Direct box (9), temperature transducer (10), one-way valve (11), speed probe (12) and engine control box (13);

Described gear pump (1) filler opening is connected with hydraulic oil container (2), and oil outlet is connected with the P mouth of pressure-compensated valve (4) with electric proportional reversing valve (5) respectively; Pressure-compensated valve (4) is connected with radiator (3) import, and radiator (3) outlet is connected with hydraulic oil container (2);

Described electric proportional reversing valve (5) T mouth is connected with the import of radiator (3), proportional reversing valve (5) A, B mouth is connected with the oil inlet and outlet of clockwise and anticlockwise motor (8) respectively, proportional reversing valve (5) C, D mouth is connected with the import of one-way valve (11), and the oil outlet of two one-way valves (11) is connected with pressure-compensated valve (4) a mouth; The b mouth of pressure-compensated valve (4) is connected with the oil outlet of gear pump (1);

Described ECU Direct box (9) is connected with electric proportional reversing valve (5), and described temperature transducer (10) is connected with ECU Direct box (9), and loads the inlet of radiator (3); Described speed probe (12) is integrated in clockwise and anticlockwise motor (8) and is above connected with ECU Direct box (9), the tach signal of Real-time Collection clockwise and anticlockwise motor (8); ECU Direct box (9) is connected with engine control box (13), the tach signal of Real-time Collection motor; Described ECU Direct box (9) is connected with instruction invert button (14).

2. loader fans drive hydraulic system according to claim 1, it is characterized in that, described temperature transducer (10) is provided with four, be respectively used to the temperature signal gathering cooling liquid, hydraulic oil, torque-converters oil, middle cold air, described radiator (3) is provided with four, and four temperature transducers (10) are loaded into the inlet of four radiators (3) respectively.

3. loader fans drive hydraulic system according to claim 1, is characterized in that, is integrated with safety valve (6) and one-way valve (7) in described clockwise and anticlockwise motor (8); When the pressure that system pressure sets higher than safety valve (6), safety valve (6) is opened, and fluid directly flows through one-way valve (7) oil sump tank from safety valve (6).