JPS59119401A - Control device of load having delay element - Google Patents

Abstract

PURPOSE:To make a load conform to a command signal which rises in the shape of a ramp by converting the command signal which rises in the shape of a ramp to a signal having a rise end like a step. CONSTITUTION:A titled device is provided with a trigger circuit 8 for inputting a command signal S1 which rises in the shape of a ramp, and outputting a trigger signal S4 at the initial time point of a rise of this signal. Also, this device is provided with a function generator 9 which is triggered by the trigger signal S4 and generates a signal S5 which rises steeply. Also, an adder 10 for applying the signal S5 to the command signal S1 is provided, and an output signal S1' of this adder 10 is applied to an adder 4. By forming in this way, the signal S1' becomes a signal having a rise end like a step. Accordingly, a load having a delay element can be made to conform to the command signal which rises in the shape of a ramp.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a load having a delay element. It relates to a device to be controlled.

A so-called hydraulic transmission is equipped with a hydraulic pump operated by an engine and a hydraulic motor operated by pressure oil discharged from the pump, and travels with the output of the motor by changing the swash plate angle of the pump and motor. This is to change the speed of the vehicle.

FIG. 1 shows a device for controlling the swash plate of the hydraulic pump or hydraulic motor, and this device includes a potentiometer 2 that outputs a command signal S1 corresponding to the operating angle of the manual operation lever l, the signal SL and a position sensor. A signal S indicating the deviation from the output signal S of No. 3.

A servo valve 6 inputs the signal S through an amplifier 5, and an actuator 7 (hydraulic servo cylinder) controlled by the servo valve 6.

The actuator 7 is connected to the swash plate of the hydraulic pump (or hydraulic motor), and therefore, when the actuator 7 is displaced, the angle of the swash plate changes. Further, the position sensor 3 outputs a signal S2 corresponding to the displacement position of the actuator 7 in conjunction with the actuator 7.

Now, when the lever 1 is operated, the output voltage of the potentiometer 2 changes in the manner shown in FIGS. 2a and 2b, depending on the amount of displacement. That is, it takes a certain amount of time 1. to displace the lever iy by a predetermined amount. (
0.2 to 0.3 seconds), the signal S1 rises in a curved line at the rise time t1.

By the way, the armature of the servo valve 6 (not shown)
For example, in response to the change a in the signal S□ shown in FIG. 2, the valve mechanism of the servo valve 6 ( (not shown) and the actuator 7 have a delay element, so that the displacement operation of the armature is delayed by a time t2, as shown in characteristic d in FIG. 3, with respect to the displacement of the armature.

When the operation of the actuator 7 is delayed, the operation of the swash plate of the hydraulic pump (hydraulic motor) driven by the actuator is also delayed, which significantly impairs the operator's sense of operation. That is, since the swash plate does not respond promptly to the operation of the lever 1, the timing of the gear shift operation intended by the operator is different from the timing of the gear shift operation of the vehicle, and as a result, the coordination between man and machine is improved. It will no longer be carried out.

In view of the above-mentioned situation, the present invention aims to provide a control device capable of causing a load to immediately respond to a command signal that rises in a ramp-like manner.

Therefore, in the present invention, a signal generator that generates a signal with a predetermined time width with a steep rise h''-, and means for adding an output signal of this signal generator to a command signal are provided, and the signal generator is The trigger is set at the rising edge of the command signal.

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

FIG. 4 is a block diagram showing an embodiment of the control device according to the present invention. In this figure, the same elements as those shown in FIG. 1 are given the same reference numerals.

The device according to this WM example includes a trigger circuit 8 which inputs a command signal S output from the potentiometer 2 and outputs a trigger signal s4 shown in FIG. Signal S.

The signal sllll as shown in the same figure (C) is triggered by
A force output function generator (signal generator) 9 and an adder 10 which adds the signal S to the command signal S1 are included, and the output signal S'I of the adder 1O is added to the adder 4. is configured to allow input.

The output signal S of the 15El number generator 9 has a waveform that rises steeply by θ and then falls exponentially, and its time width is approximately the rise time of the command signal S1 t+(0,
2 to 0.3 seconds).

When the lever 1 is operated and the command signal S, which rises in the ramp shape shown in FIG. As shown in the same figure (@) in which the output signal S and are incremented, a signal S is output. This signal S has a step-like rising edge, so that from the input point of the command signal S, A large current flows through the drive coil of the servo valve 6, thereby improving the responsiveness of the actuator 7 to the command signal S1. In other words, the actuator 7 changes in the manner shown by curve e in FIG. As a result, the response delay time of the actuator 7 is reduced compared to the delay time t of the conventional device, as shown by t3 in the figure. Therefore, according to the device of this embodiment, Swash plate control, that is, speed change, can be carried out in immediate response to the operator's lever operation.

Note that the time width and waveform of the output signal S of the function generator 9 can be changed as appropriate depending on the characteristics of the load. For example, a rectangular or right triangular signal S may be output from the function generator 9, and the time width of the signal S may be set to the rise time t1 of the command signal S1.
You may also set it to be slightly shorter or more broiled.

It goes without saying that the invention can be applied to things other than swash plate control of hydraulic transmissions.

According to Misfire 1, the load with the □ delay element should immediately respond to the command signal rising in a ramp-like manner around b''-C.

Therefore, if applied to the swash plate side leg of the hydraulic transmission shown in the example, it is possible to match the operator's gear shift timing with the actual gear shift timing of the heavy object, thereby providing a good operating feel. It will be done.

[Brief explanation of the drawing]

Fig. 1 is a block diagram showing an example of a conventional device for controlling the swash plate of a hydraulic transmission, Fig. 2 is a diagram illustrating one example of a change in a command signal corresponding to a lever operation,
3 is a diagram illustrating aspects of armature displacement and actuator displacement of a servo valve, FIG. 4 is a block diagram illustrating an embodiment of the control device according to the present invention, and FIG. 5 is the device shown in FIG. 4. Al with a time chart to explain the action of. 1... Lever, 2... Potentiometer, 4.10
...Adder, 5...Amplifier, 6...Servo valve, 7
... Actuator, 8... Trigger circuit, 9... Function generator.

Claims (1)

[Claims] A device for controlling a load having a delay element using a command signal that rises in a ramp-like manner includes a signal generator that generates a signal that rises steeply for a predetermined period of time, and means for adding an output signal of this signal generator to the command signal. A control device for a load having a delay element, characterized in that the signal generator is triggered at a rising edge of the command signal.