KR100244098B1 - Engine rpm control method for hydraulic type construction machine - Google Patents

Abstract

The present invention relates to a prime mover rotation speed control method of a hydraulic construction machine, and more particularly, a prime mover, a variable displacement hydraulic pump driven by the prime mover, the prime mover rotational speed adjusting means and rotational speed detection means, A throttle drive motor position detecting means for detecting the position of the throttle drive motor for rotating the throttle lever of the prime mover, a flow control valve for controlling the start, stop and direction change of the actuator by adjusting the flow rate discharged from the hydraulic pump, A prime mover of a hydraulic construction machine comprising a controller for calculating pulses of the throttle drive motor in accordance with a signal input from a means, a throttle drive motor for driving a throttle lever in accordance with a signal from the controller, and an electromagnetic ratio valve for adjusting a pump swash plate. In the rotation speed control method, each stage of the prime mover rotation speed adjusting means A first step of storing the no-load target prime mover rotation speed in a storage location of the controller in advance, and receiving the current prime mover speed adjusting step from the prime mover speed adjusting means after starting the prime mover. A second step of determining whether or not it is selected, and when a signal input from the prime mover rotation speed adjusting means is first selected after starting the prime mover, the prime mover reference speed feedback control is performed; It provides a prime mover speed control method of a hydraulic construction machine comprising a third step of performing a reference control.

Description

Primer speed control method of hydraulic construction machine

The present invention relates to a prime mover speed control method of a hydraulic construction machine, and more particularly, to set the prime mover rotation speed to an arbitrary rotation speed according to the working environment and working characteristics of the hydraulic construction machine, The present invention relates to a prime mover rotation speed control method of a hydraulic construction machine that enables the output characteristics of a prime mover to be optimally set using an engine speed detecting means and a throttle drive motor position detecting means.

As shown in FIG. 1, the prime mover-pump system of a hydraulic construction machine according to the prior art is directly driven by a prime mover 1 of a diesel engine, and the prime mover 1 drives the mechanical energy of the prime mover 1. At least one variable displacement hydraulic pump 2 for converting into energy, an actuator 4 connected to and driven by the hydraulic pump 2, and the hydraulic pump 2 and the actuator 4 are installed between the hydraulic fluid And a flow rate control valve 3 for controlling the flow direction of the actuator 4 to control the start, stop and direction change of the actuator 4 described above.

In addition, the control method of the prime mover-pump system of the hydraulic construction machine configured as described above, two methods are generally used, that is, a feedback control method based on the prime mover rotation speed, as shown in FIG. As shown in the drawing, a method of feedback control of the position of the throttle drive motor is used.

In the method of controlling feedback based on the prime mover rotation speed, the controller 10 sets the no-load target prime mover rotation speed based on a signal from the prime mover rotation speed adjusting means 11, and the prime mover rotation speed detecting means 12 Comparing with the present prime mover rotation speed obtained from the above and the no-load target prime mover rotation speed described above, the throttle drive motor 13 is driven so that the present prime mover rotation speed falls within a certain tolerance range of the target rotation speed, and the throttle control mechanism 9 By rotating the throttle lever 8 through), the feedback control can be controlled based on the prime mover rotation speed to the desired output characteristic state of the prime mover 1.

However, the above control method has no problem when the target rotational speed is set from the input of the prime mover rotation speed adjusting means 11 under no load, but when the load is generated during operation, the controlled prime mover characteristics are to be set. There was a problem of being different from the prime mover.

On the other hand, the feedback control method based on the position of the throttle drive motor described above, the throttle drive motor position detection means 14 without using the prime mover rotation speed detection means shown in Figure 1, the prime mover rotation On the basis of the signal from the speed adjusting means 11, the controller 10 sets the target throttle position corresponding to the target rotational speed, and the current throttle driving motor 13 from the throttle drive motor position detecting means 14 is set. By rotating the throttle lever 8 through the drive and throttle control mechanism 9, it is possible to control the feedback based on the position of the throttle drive motor 13 to the desired output characteristic state of the prime mover 1.

However, the latter method also controls the prime mover characteristics by the tolerances of the throttle control mechanism 9 connecting the throttle drive motor 13 and the throttle lever 8 and the mechanical flow due to aging change due to long time operation. There is a problem that is different from the prime mover characteristic to be set.

Accordingly, an object of the present invention is to provide a simple initial adjustment operation and an engine speed detecting means and a throttle drive motor position detecting means in order to set the prime mover rotation speed to an arbitrary rotation speed according to the working environment and working characteristics of a hydraulic construction machine. It is to provide the prime mover speed control method of a hydraulic construction machine that can be used to set the output characteristics of the prime mover to an optimal state, and to control the prime mover stably and with high accuracy over a long period of time.

1 is a schematic diagram for explaining a method of controlling feedback based on the prime mover rotation speed of the prime mover-pump system of a hydraulic construction machine according to the prior art,

Figure 2 is a schematic diagram for explaining a method of feedback control based on the position of the throttle drive motor of the prime mover-pump system of the hydraulic construction machine according to the prior art,

3 is a schematic view for explaining a prime mover speed control method of a hydraulic construction machine according to an embodiment of the present invention,

Figure 4 is a flow chart for explaining a prime mover speed control method of a hydraulic construction machine according to an embodiment of the present invention.

* Explanation of symbols for the main parts of the drawings

1: prime mover

2: variable displacement hydraulic pump

3: flow control valve

4: actuator

8: throttle lever

9: throttle control mechanism

10: controller

11: Motor speed control means

12: prime mover speed detecting means

13: throttle drive motor

14: Throttle drive motor position detection means

15: Electronic proportional pressure reducing valve for pump swash plate adjustment

An object of the present invention described above is a position of a prime mover, a variable displacement hydraulic pump driven by the prime mover, the prime mover rotational speed adjusting means and the rotary speed detecting means, and a throttle drive motor for rotating the throttle lever of the prime mover. A throttle drive motor position detecting means for detecting a flow rate, a flow rate control valve controlling a start, stop, and direction change of the actuator by adjusting a flow rate discharged from the hydraulic pump, and the throttle drive motor according to a signal input from the means. A prime mover rotation speed control method for a hydraulic construction machine comprising a controller for calculating a pulse, a throttle drive motor for driving a throttle lever in accordance with a signal from the controller, and an electromagnetic ratio valve for adjusting a swash plate. The no-load target prime mover rotation speed for each stage of the means is stored in the controller. A second step of pre-storing the first step, and a step of determining whether the current step is first selected after starting the prime mover by receiving a current prime mover speed adjusting step from the prime mover speed adjusting means after starting the prime mover; When the signal input from the prime mover rotation speed control means is selected for the first time after starting the prime mover, and performs the prime mover speed reference feedback control, and if not selected for the first time includes a third step of performing the throttle drive motor position reference control It is achieved by providing a prime mover speed control method of a hydraulic construction machine characterized in that.

According to a preferred aspect of the present invention, the step of minimizing the discharge flow rate of the hydraulic pump by sending a maximum current to the electronic proportional pressure reducing valve for adjusting the pump swash plate before driving the throttle of the prime mover during the motor rotational speed reference feedback control It is characterized by including.

Another desirable feature of the present invention is to output the current value corresponding to the current stage of the prime mover rotational speed control means to the pump swash plate adjustment electronic proportional pressure reducing valve after the prime mover rotational speed reference feedback control is completed, the throttle drive motor And setting the current position value of the position detection means to the target position value of the current stage of the prime mover rotation speed adjusting means.

Hereinafter, a preferred embodiment of the present invention will be described in detail according to the accompanying drawings.

Figure 3 is a schematic diagram for explaining the prime mover speed control method of a hydraulic construction machine according to an embodiment of the present invention, Figure 4 is to explain the prime mover speed control method of a hydraulic construction machine according to an embodiment of the present invention It is a flow chart for.

As shown in detail in the drawings, the prime mover-pump system of the hydraulic construction machine to which the present invention is applied is driven directly by the prime mover 1 and the prime mover 1, and the mechanical energy of the prime mover 1 is transferred to the fluid energy. At least one variable displacement hydraulic pump 2 to be converted into an actuator, an actuator 4 connected to and driven by the hydraulic pump 2, and a hydraulic oil installed between the hydraulic pump 2 and the actuator 4 described above. A flow rate control valve 3 for controlling the start, stop, and direction change of the actuator 4 described above by controlling the flow direction of the actuator 4, the rotational speed adjusting means 11 and the rotational speed detecting means 12 of the prime mover, and the prime mover. A throttle drive motor position detecting means (14) for detecting the position of the throttle drive motor (13) for rotating the throttle lever (8) of the throttle lever (8), and the throttle drive motor (13) described above in accordance with signals input from the respective means described above. To calculate the pulse that drives Pump swash plate adjustment for adjusting the swash plate inclination angle of the controller 10, the throttle drive motor 13 for driving the throttle lever 8 described above according to the signal from the controller 10, and the hydraulic pump 2 described above. The electromagnetic pressure reducing valve 15 is provided.

Referring to the control method according to the present invention for the hydraulic construction machine configured as described above are as follows.

The no-load target prime mover rotational speed value of each stage of the prime mover rotational speed adjusting means 11 is stored in the storage of the controller 10 described above, and when the prime mover 1 is started, the controller 10 performs the aforementioned prime mover. Detects the current stage from the rotational speed adjusting means 11 to determine whether the current stage is first selected after starting the prime mover 1, and in the case of the first selection, the maximum current in the above-described solenoid pressure reducing valve 15 for adjusting the pump swash plate. Reduce the discharge flow rate of the hydraulic pump (2) to the minimum, and then control the prime mover speed reference to match the target prime mover speed, and then adjust the current position of the throttle drive motor (13) to the target position value of the current stage. If it is not selected for the first time, the throttle drive motor position-based feedback control is performed to the target position set at the time of initial selection. The throttle lever 8 is moved to the force characteristic state.

Hereinafter, the control method of the present invention will be described in more detail with reference to FIG. 4 in each step.

In step 1 (20), the no-load target prime mover rotational speed Nt of each stage of the prime mover rotational speed adjusting means 11 is stored in the storage of the controller 10, and the flow advances to step 2.

In step 2 (21), it is judged whether the prime mover 1 has been started, and if the prime mover 1 is not started, it waits continuously, and when the prime mover 1 starts, it progresses to step 3.

In step 3 (22), the value of the current step is input from the prime mover rotation speed adjusting means (11), and the flow advances to step 4.

In step 4 (23), it is determined whether the current step inputted from the prime mover rotation speed adjusting means is first selected after starting, and if it is selected for the first time, the process proceeds to step 5; otherwise, the process proceeds to step 13.

In step 5 (24), the no-load target prime mover rotation speed Nt corresponding to the current step of the prime mover rotation speed adjusting means 11 is set among the values stored in step 1 (20) described above, and the procedure proceeds to step 6.

In step 6 (25), the present prime mover rotational speed N is input from the prime mover rotational speed adjusting means 11, and the flow advances to step 7.

In step 7 (26), the calculation P1 = f (Nt, N, the throttle drive motor specification, the throttle total) which takes as parameters the Nt, N and throttle drive motor 13 specifications and the throttle total rotation angle specification set in the above-described steps. The number of pulses P1 to be output to the throttle drive motor 13 is calculated through the rotation angle specification) and the process proceeds to step 8.

In step 8 (27), the maximum current is supplied to the electromagnetic proportional pressure reducing valve 15 for adjusting the pump swash plate to minimize the discharge flow rate of the hydraulic pump 2 and proceed to step 9.

In step 9 (28), the pulse number P1 calculated in the above-mentioned step 7 (26) is output to the throttle drive motor 13, and it progresses to step 10. FIG.

In step 10 (29), if the above-mentioned | Nt-N | is calculated and the magnitude is larger than the constant tolerance range Э1, the process proceeds to step 6, and the motor rotational speed reference feedback control is continued, otherwise the process proceeds to step 11 do.

In step 11 (30), the electric current value corresponding to the current stage of the prime mover rotational speed adjusting means 11 is output to the pump swash plate adjustment electromagnetic proportional pressure reducing valve 15, and the flow proceeds to step 12.

In step 12 (31), the current position value θ of the throttle drive motor position detecting means 14 is set to the target position value θt of the current stage of the prime mover rotational speed adjusting means 11, and this value is set by the controller 10. After saving to the memory, go to Step 3 to form an infinite loop.

In step 13 (32), the target position value [theta] t of the throttle drive motor 13 corresponding to the present stage of the prime mover rotation speed adjusting means 11 is set, and the procedure proceeds to step 14.

In step 14 (33), the current position value θ of the throttle drive motor 13 is input from the throttle drive motor position detection means 14, and the flow advances to step 15.

In step 15 (34), the throttle drive motor 13 is operated via calculation P2 = f (Nt, N, throttle drive motor specification) parameterizing the θ t, θ and throttle drive motor 13 specifications in the above-described steps. Calculate the number of pulses P2 to be outputted and proceed to step 16.

In step 16 (35), the above-described pulse number P2 is outputted to the throttle drive motor 13, and the flow proceeds to step 17.

In step 17 (36), if the above-mentioned &thetas; t- & theta is calculated and the magnitude is larger than the constant tolerance range Э2, the process proceeds to step 14, and the throttle drive motor position reference feedback control is continued, otherwise, the process proceeds to step 3. do.

At this time, the constant tolerance range Э2 means the throttle drive motor position detection means 14 and mechanical errors allowed by the system.

As described above, the prime mover speed control method of the hydraulic construction machine according to the present invention is a combination of the load state of the machine and the prime mover speed control device through the mixed performance of the position reference control and the prime mover reference control of the throttle drive motor It is possible to optimally set the prime mover output characteristics regardless of the tolerance, which can solve the problem of different prime mover output characteristics, and improve the basic performance of construction machinery controlling the prime mover speed. That will have the advantage.

Claims (3)

Position detection of the throttle drive motor for detecting the position of the prime mover, the variable displacement hydraulic pump driven by the prime mover, the prime mover rotation speed adjusting means and the rotation speed detecting means, and the throttle drive motor for rotating the throttle lever of the prime mover. Means, a flow rate control valve for controlling the start, stop and direction change of the actuator by adjusting the flow rate discharged from the hydraulic pump, a controller for calculating pulses of the throttle drive motor in accordance with a signal input from the means, In the prime mover rotation speed control method of a hydraulic construction machine comprising a throttle drive motor for driving the throttle lever in response to a signal from the controller, and an electromagnetic ratio valve for adjusting the swash plate, A first step of previously storing the no-load target prime mover rotational speed of each stage of the prime mover rotational speed adjusting means in a storage location of the controller; A second step of determining whether a current step is first selected after starting the prime mover by receiving a current prime mover speed adjusting step from the prime mover speed adjusting means after starting the prime mover; When the signal input from the prime mover rotation speed control means is selected for the first time after starting the prime mover, and performs the prime mover speed reference feedback control, and if not selected for the first time includes a third step of performing the throttle drive motor position reference control A prime mover speed control method of a hydraulic construction machine characterized in that. The method of claim 1, further comprising: minimizing the discharge flow rate of the hydraulic pump by sending a maximum current to the electromagnetic proportional pressure reducing valve for adjusting the pump swash plate before driving the throttle of the prime mover when the prime mover rotation speed reference feedback is performed. A prime mover speed control method of a hydraulic construction machine, characterized in that. According to claim 1, After the motor rotational speed reference feedback control is completed, outputs a current value corresponding to the current stage of the motor rotational speed adjusting means to the electronic proportional pressure reducing valve for adjusting the pump swash plate, the throttle drive motor position detection means A method of controlling the prime mover speed of a hydraulic construction machine, characterized by further comprising the step of setting the current position value of the prime mover rotational speed adjusting means to the target position value of the current stage.

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