JPH051681Y2 - - Google Patents

Description

[Detailed description of the invention] (1) Industrial application field The present invention relates to an operating device for an aerial work vehicle, etc.

(2) Conventional technology Conventionally, in an aerial work vehicle equipped with a work platform at the tip of the boom, an operation lever is provided on the work platform and a switching valve is installed at the bottom to control the movement of the boom from above the platform. In the case of an aerial work vehicle with an insulated boom, an optical cable was strung between the work platform and the lower part, and the operation of the boom was controlled by optical signals.

(3) Problems that the invention aims to solve However, in the conventional operating device, the operating signal is converted into a digital signal in order to operate each actuator using a single optical cable, so the signal that controls the switching valve is The problem is that the step-like signal is proportional to the amount of lever operation, and the shock is large during operation, making it difficult to operate smoothly, and increasing the number of steps in the operation signal for smooth operation requires a large amount of cost. It was hot.

(4) Means for solving the problem In order to solve the above problem, the present invention converts the signal emitted from the transmitting device that emits a signal proportional to the amount of operation of the operating lever into an A/D converter. The digital signal is converted into a digital signal by a parallel/serial converter, the digital signal is converted into a serial signal by a parallel/serial converter, and the signal is sent to a serial/parallel converter. In an operating device for a work vehicle that controls an electromagnetic proportional valve using a step signal converted by It is designed to control a valve.

(5) Effect With the above configuration, the step signal converted by the D/A converter becomes a substantially linear smooth signal by passing through the time constant circuit, thereby smoothly controlling the electromagnetic switching valve.

(6) Examples Examples of the present invention will be described below with reference to the drawings.

Fig. 1 shows an aerial work vehicle, in which a telescoping boom 3 is pivotally supported on a turntable 2 provided on the vehicle body 1, and the telescoping boom 3 is raised and lowered by the expansion and contraction of a luffing cylinder 4, and a built-in telescoping cylinder (Fig. (not shown).

A workbench 5 is held in equilibrium at the tip of the telescopic boom 3, and the workbench 5 is equipped with an operating lever 6 for operating operations such as raising and lowering the telescopic boom 3, extending and contracting it, and rotating the turntable 2.

Then, as shown in FIG. 2, a transmitting device 7 such as a potentiometer is operated by the operating lever 6.
The transmitting device 7 transmits a signal proportional to the amount of operation of the operating lever 6. The signal transmitted from the transmitting device 7 is sent to the A/D converter 8 and converted into a several-bit digital signal, and this digital signal is converted into a serial signal by the parallel/serial converter 9.
This serial signal is converted into an optical signal by an optical transmitter 10 and sent to an optical receiver 12 provided on the turntable 2 through an optical fiber cable 11 stretched along the telescopic boom 3. Optical receiver 1
The optical signal sent to 2 is converted into a serial signal,
This serial signal is sent to serial/parallel converter 1
3, it is returned to a parallel signal. Each parallel signal is converted from a digital signal to an analog signal by a D/A converter 14, and this analog signal is converted into a time constant circuit 1 that converts the analog signal into a smooth signal.
5 and is sent to the electromagnetic proportional valve 16.

With the above configuration, the operation signal converted by the D/A converter 14 is a stepped signal as shown in FIG. However, the time constant circuit 15 converts the stepped signal converted by the D/A converter 14 into a substantially linear triangular waveform. As shown in the figure, the step-like signal becomes a substantially linear smooth signal, and this signal allows the electromagnetic proportional valve 16 to be smoothly operated from start to stop.

(7) Effects of the invention As described above, the present invention provides a working vehicle operating device that has a simple structure, is low cost, and can be operated smoothly, and the present invention improves the operability of a working vehicle. It is effective for

[Brief explanation of drawings]

The drawings show an embodiment of the present invention, in which Fig. 1 is a side view of the aerial work vehicle, Fig. 2 is a block diagram of the operating device, Fig. 3 is a diagram of the input signal of the time constant circuit, and Fig. 4 is a diagram of the input signal of the time constant circuit.
The figure is a diagram of the output signal of the time constant circuit. 6... Operation lever, 7... Transmission device, 8...
A/D converter, 9... Parallel/serial converter, 10... Optical transmitter, 11... Optical fiber cable, 12... Optical receiver, 13... Serial/parallel converter, 14... D/ A converter, 15...
Time constant circuit, 16...Solenoid proportional valve.

Claims (1)

[Scope of utility model registration request] A signal transmitted from a transmitting device that transmits a signal proportional to the amount of operation of the operating lever is converted into a digital signal by an A/D converter, and this digital signal is converted into a serial signal by a parallel/serial converter. In an operation device for a work vehicle that controls an electromagnetic proportional valve using a step signal that is transmitted to a parallel converter and converted into a parallel signal by a serial/parallel converter and converted by a D/A converter, the step signal is converted into a parallel signal by a D/A converter. An operating device for a work vehicle, characterized in that a time constant circuit converts a step-like signal into a smooth signal to smooth the signal into a substantially linear signal to control an electromagnetic proportional valve.