KR950002125B1 - Best driving control method of excavator - Google Patents

Abstract

The method enables the vehicle to preheat the working hydraulic oil of the hydraulic pump for preparing normal operation. The system comprises a temperature detecting sensor (12) for receiving the current signal according to the oil temperature (Q) of primary / secondary / tertiary hydraulic pumps (2,3,4) and manipulating degree (θ1) of acutator lever / pedal (10); swash-plate angle adjusting valves (2b,3b) for outputting controlling current (Imax); solenoid valves (7,14) for outputting controlling currents (Ia,Ib); a logic valve (6) for passing the hydraulic oil discharged from the primary / secondary pumps (2,4). When the manipulating degree is zero and the oil temp. (θ1) is below minimum temp. (50≰C), the temp. is increased to the proper temp. (55≰C).

Description

Heavy Equipment Optimal Preheating Operation Control Method

1 is a schematic partial hydraulic circuit diagram of an excavator according to an embodiment of the present invention.

2 is a flow chart of the optimal preheating operation control method of the present invention.

* Explanation of symbols for main parts of the drawings

1: Engine 2, 3, 4: 1st, 2, 3 hydraulic pump

2a, 3a: swash plate angle adjusting mechanism 2b, 3b: swash plate angle adjusting valve

5: multiple control valve 6: logic valve

7: solenoid valve 8: relief valve

9: controller 10: operation lever / pedal

11: amplifier 12: temperature sensor

13 alarm 14 solenoid valve

15: tank

The present invention relates to a method for controlling heavy equipment optimal preheating operation, and in particular, the optimum preheating operation control of the heavy equipment which enables the smooth operation of the heavy equipment by automatically raising the hydraulic oil of the hydraulic pump to a predetermined temperature before the normal operation of the heavy equipment. It is about a method.

In general, all the equipment or vehicles driven by the engine have been preheated by sufficient preheating operation prior to normal operation. Especially in heavy equipment, not only the temperature of the engine but also the temperature of each actuator and hydraulic pump oil There is a need to raise to an appropriate temperature.

However, the conventional heavy equipment is not equipped with a means to detect the temperature of the hydraulic oil and increase the temperature to the appropriate temperature, so that the hydraulic oil temperature is judged by the driver's experience according to the ambient temperature condition, and the heavy equipment is preheated for a predetermined time to increase the temperature. However, there was a waste of energy due to excessive consumption of preheating operation time due to the lack of optimum preheating operation.

Therefore, the present invention was devised to solve the above problems, and during the preheating operation of heavy equipment, each actuator and hydraulic pump hydraulic oil temperature is automatically raised to the minimum temperature at a minimum time, and waste of time and energy due to excessive preheating operation. The purpose is to provide a method for controlling the optimal preheating operation of heavy equipment to eliminate the need for smooth normal operation.

The present invention for achieving the above object, receives a current signal according to the operating oil temperature of the first, second, third hydraulic pumps and the operating amount (θ ₁ ) of the operation lever / pedal of each actuator via a temperature sensor When the operating amount θ ₁ is zero and the operating oil temperature Q is lower than the allowable minimum temperature (50 ° C.), the control current value Imax is controlled by the swash plate angle control valve so that the flow rate discharged from the first and second hydraulic pumps is maximized. And outputs the control current values (Ia, Ib) to the solenoid valve and compensates the temperature according to the pressure loss generated by the resistance when the pressure oil discharged from the first and second hydraulic pumps passes through the relief valve. Raise the oil temperature (Q) to an appropriate temperature (55 ° C), and if you are working while the oil temperature (Q) is below the allowable minimum temperature (50 ° C), call the driver to alert you. At least By raising the working oil temperature is dropped to prevent a waste of time and energy due to the excessive pre-heating operation by giving.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 shows a schematic partial hydraulic circuit of an excavator applied as an embodiment of the present invention, in which first and second hydraulic pumps 2 and 3 are supplied to supply hydraulic pressure of each actuator to an output shaft of an engine 1. And a third hydraulic pump 4 for supplying internal pilot pressure oil are connected in series, and the first and second hydraulic pumps 2 and 3 discharge the pressure oil discharged to be supplied to each actuator. 5) is connected, and a logic valve 6 and a solenoid valve 7 are sequentially connected to the control valve 5 in series.

The third hydraulic pump 4 has a swash plate adjustment valve such that the discharged pressure oil is operated by the internal pilot pressure oil of each of the swash plate angle adjustment openings 2a and 3a of the first and second hydraulic pumps 2 and 3. (2b, 3b) is connected, and is installed between the multiple control valve (5) and each of the hydraulic pump (2,3) to selectively set the pressure of the relief valve (8) for preventing overload in the flow path Each sprue 8a of the relief valve 8 is connected to adjust it.

Further, on the input side of the controller 9 for applying a predetermined control current to the swash plate adjustment valves 2b and 3b, an operation lever / pedal 10 for operating each actuator and the operation lever / pedal 10 Amplifier 11 for amplifying the control current value calculated according to the operation amount of the) and the temperature sensor 12 for detecting the operating oil temperature of the first, second, third hydraulic pumps (2, 3, 4) is connected On the other hand, on the output side, the alarm 13, the solenoid valve 7 and the relief valve for alerting the driver when the operating oil temperature detected by the temperature sensor 12 is below the allowable minimum temperature Solenoid valves 14 for selectively adjusting the set pressure of 8) are respectively connected.

2 shows a flow chart in the control method of the present invention programmed in the controller 9. First, in steps 100 and 101, the first, second and third hydraulic pumps 2, 3 and 4 are shown. The operating oil temperature (Q) and the operating amount (θ ₁ ) of the operating lever / pedal 10 of each actuator are read. 50 ° C.), in which case the hydraulic oil temperature Q is returned to the beginning when the allowable minimum temperature (50 ° C.) is greater, whereas when it is less than 50 ° C., the procedure 101 is again performed in step 103. In this case, it is determined whether the manipulated variable θ ₁ is zero. In this case, when the manipulated variable θ ₁ is not zero, the driver outputs a current Ic to the alarm 13 in step 110 to alert the driver. Ventilate

When the manipulated value θ ₁ is zero in the procedure 103, the swash plate angle regulating valves 2b and 3b are connected to the procedure 104 to maximize the flow rate discharged from the first and second pumps 2 and 3. Output current Ia to the solenoid valve 7 in step 105 to prevent the pressure oil discharged from the first and second pumps 2 and 3 from being drained to the tank 15. In addition to the zoom, the relief valve 8 is output so that the set pressure is 80 kg / cm 2, and the pressure loss discharged from the first and second pumps 2 and 3 passes through the logic valve 6. This allows the oil temperature to rise.

In addition, after the procedure 105, the operating oil temperature Q is sensed again in the procedure 106, and the procedure 107 determines whether the detected temperature Q is equal to or higher than the appropriate temperature (55 ° C). If the temperature is lower than the appropriate temperature (55 ° C), the flow returns to the procedure 104, and the operating oil temperature Q is continuously increased by the procedures 104 and 105, while the proper temperature (55 ° C) or more is increased. If the control current value Imax, Ia, Ib outputted in the procedures 104 and 105 in steps 108 and 109 are blocked, the control process of the present invention is completed by returning to the normal state. .

As described above, the method for controlling the optimum preheating operation of the heavy equipment of the present invention automatically raises the operating oil temperature of each actuator and the hydraulic pump to the appropriate temperature at the minimum time during the preheating operation to eliminate waste of time and energy due to excessive preheating operation, and the operating oil temperature Working at temperatures below the permissible minimum temperature has the effect of alerting the operator to prevent overload on heavy equipment.

Claims (1)

The current according to the operating oil temperature (Q) of the first, second, third hydraulic pumps (2, 3, 4) and the operating amount (θ ₁ ) of the operating lever / pedal (10) of each actuator via the temperature sensor (12). The swash plate receives a signal so that the flow rate discharged from the first and second hydraulic pumps 2 and 3 becomes maximum when the operation amount θ ₁ is zero and the operating oil temperature Q is equal to or lower than the allowable minimum temperature (50 ° C.). The control current values Imax are output to the respective control valves 2b and 3b, and the control current values Ia and Ib are output to the solenoid valves 7 and 14, respectively. Optimal preheating operation control method for heavy equipment which is to raise the hydraulic oil temperature (Q) to an appropriate temperature (55 ℃) by the temperature compensation according to the pressure loss caused by the flow resistance when the discharged pressure oil passes through the logic valve (6).