JPH0133599Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to an operation regulating device for an aerial work vehicle equipped with a work platform and a lifting device at the tip of a boom.

For aerial work vehicles equipped with lifting equipment,
In order to prevent the work vehicle from tipping over or being damaged, a work range regulating device or moment limiter is installed to restrict its operation when the work vehicle reaches a certain position or a certain load state. ing. However, conventional operation regulating devices simply restrict the operation of the boom in the direction that increases the overturning moment, that is, the extension of the boom and the operation of raising and lowering the boom, resulting in excessive loads acting on the work vehicle when lifting a load. It was not possible to prevent the work vehicle from falling or being damaged due to the accident.

The present invention has been developed in view of the above circumstances, and includes a moment limiter that outputs when the overturning moment acting on the aerial work vehicle approaches the overturning limit moment, and detects the lifting state of the load by the lifting device. A lifting detector, a boom extension regulating device, a boom raising/lowering regulating device,
When the boom hoisting regulation device, the hoisting regulation device of the hoisting device, and the moment limiter are output alone or after the output of the hoisting detector, the boom extension regulating device and the boom hoisting lowering regulation device are activated to detect the moment limiter and hoisting. Equipped with an operation regulation circuit that activates the boom extension regulation device, boom raising/lowering regulation device, boom raising/lowering regulation device, and hoisting device hoisting regulation device when the equipment outputs simultaneously, the work vehicle will never be overloaded. The object of the present invention is to provide an operation regulating device for an aerial work vehicle equipped with a lifting device, which has never been found before.

Embodiments of the present invention will be described below with reference to the drawings. As shown in Figure 1, the aerial work vehicle has a body 1
A telescopic boom 3 is pivotally supported on a rotating base 2 provided in do. A work platform 4 and a lifting device 5 are held in equilibrium at the tip of the telescopic boom 3, and the lifting device 5 has a lifting hook 1 at the tip by a winch driven by a hydraulic motor 8.
0 is wound up and let out.

Fig. 2 shows the hydraulic circuit of the aerial work vehicle, and the discharge pipe of the hydraulic pump 13 is connected to the lower switching valves 15, 16, 1 provided at the base of the swing base or the telescopic boom.
7 and the upper switching valve 25, 2 provided on the workbench.
6, 27, and 18, the swing motor 11 that rotates the swing base is operated by the switching valve 15 and the switching valve 25, the undulating cylinder 6 is operated by the switching valve 16 and the switching valve 26, and the switching valve 17 and The telescopic cylinder 7 is operated by the switching valve 27, and the switching valve 1
8 operates the hydraulic motor 8 of the lifting device. A boom hoisting-up regulating device, a boom hoisting-lowering regulating device, and a boom extension regulating device are provided in the extension-side conduit and contraction-side conduit of the hoisting cylinder 6, the extension-side conduit of the telescopic cylinder 7, and the hoisting-side conduit of the hydraulic motor 8, respectively. and a one-way shut-off valve 19, 2 which is switched by a solenoid and is a hoisting regulating device.
0, 21, 22 are inserted, and the solenoids 19S, 20S, 21S, 22 of each shutoff valve
By cutting off the power to S, oil supply to each actuator from each conduit into which the shutoff valve is inserted is cut off.

Figure 3 shows an operation regulation circuit, and 23 is a moment limiter, which compares the overturning moment acting on the work vehicle with the overturning limit moment, and detects when the overturning moment acting on the work vehicle approaches the overturning limit moment. The current flowing through relays R1 and 28 is cut off. A lifting detector 24 that detects lifting of a load by the lifting device based on the tension acting on the rope of the lifting device is connected to a self-holding circuit of relays R3 and 30 operated by the A contacts 31 of relays R2 and 29 and relays R1 and 28. energized when the load is lifted. Relay R1,2
The A contact 33 of No. 8 is the one-way shut-off valve 20, 2
The B contact 34 of the relay R2, 29 is connected to the solenoid 19S of the one-way shut-off valve 19, and the A contact 35 of the relay R3, 30 connected in parallel is connected to the solenoid 20S, 21S of the relay R1, 29. The A contact 36 is connected to the solenoid 22S of the one-way shutoff valve 22, and the contact 34 and the solenoid 19S are connected via a diode 37, and the contacts 35, 36, and the solenoid 22S are connected via a diode 37.

With the above configuration, when the lifting device 5 is not in use, the relays R2, 29 and relays R3, 30 are not energized, so the B contact 34 is held in the connected state, the M contact 35 is held in the disconnected state, and the moment limiter In the state where 23 is not operating, A
Since the contact 33 and the A contact 36 are in contact, all solenoids 19S, 20S, 21S, 22S
is energized, the operation of the aerial work vehicle is not regulated, and when the moment limiter 23 is activated, the A contact 33 and the A contact 36 are disconnected, and the solenoid 21
S, solenoid 20S and solenoid 22S are de-energized and the one-way shaft-off valves 21, 20,
22 is switched, and the extension of the boom, the raising and lowering of the boom, and the hoisting of the lifting device are regulated. When the moment limiter is activated after lifting a load, the lifting detector 24 is activated by lifting the load, relays R2, 29 and relays R3, 30 are energized, and the B contact 34 is disconnected. , the A contact 35 is in a closed state, but when the moment limiter 23 is not operating, all the solenoids 19S, 20S, 21S, and 22S are energized, so the operation is not restricted, and when the moment limiter 23 is operating, The A contact point 33 is turned off, the one-way shut-off valves 21 and 20 are switched, and the extension of the boom and the raising and lowering of the boom are restricted. When the moment limiter is activated by lifting a load, the lifting detector 24 is activated at the same time as the moment limiter 23 is activated, relays R1 and 28 are de-energized, and relays R2 and 29 are energized. Relays R3 and 30 are not energized because the A contact 32 of the self-holding circuit is an on-delay contact, and the A contact 33 is disconnected, and the B
Contact 34 is closed, A contact 35 and A contact 36 are also closed, and all solenoids 19 are closed.
The power to S, 20S, 21S, and 22S is cut off, and the one-way shaft-off valves 19, 20, 21, and 22 are switched to raise and lower the boom.
Extension of the boom and hoisting of the lifting device will be regulated, and lifting of loads by any operation of an aerial work vehicle equipped with a lifting device will be stopped.

As described above, according to the present invention, by regulating the operation according to the condition of the aerial work vehicle, the performance of the aerial work vehicle can be fully utilized, and the excessive overturning moment will not be applied to the work vehicle under any condition. Thus, there is provided an operation regulating device for an aerial work vehicle equipped with a lifting device that does not operate.

[Brief explanation of drawings]

The drawings show an embodiment of the present invention, and Fig. 1 is a side view of an aerial work vehicle equipped with a lifting device, Fig. 2 is a hydraulic circuit diagram of the aerial work vehicle, and Fig. 3 is an electric circuit of an operation regulation circuit. It is a diagram. 1...Vehicle body, 2...Swivel base, 3...Telescopic boom, 4...Work platform, 5...Lifting device, 6...
Lifting cylinder, 7... Telescopic cylinder, 8... Hydraulic motor, 19, 20, 21, 22... One-way shaft off valve, 19S, 20S, 21S, 22S...
... Solenoid, 23 ... Moment limiter, 2
4... Lifting detector, 28, 29, 30... Relay, 31, 33, 35, 36... A contact, 32
...On-delay A contact, 34...B contact, 37...
…diode.

Claims (1)

[Scope of utility model registration request] In an operation regulation device that regulates the operation of an aerial work vehicle when the aerial work vehicle equipped with a work platform and a lifting device at the tip of the boom reaches a certain load state,
A moment limiter that outputs when the overturning moment acting on the aerial work vehicle approaches the overturning limit moment, a lifting detector that detects the lifting state of the load by the lifting device, a boom extension regulation device, and a boom elevation/lowering regulation. The device, the boom hoisting regulation device, the hoisting regulation device of the lifting device, and the moment limiter actuate the boom extension regulation device and the boom hoisting regulation device when the moment limiter outputs alone or after the output of the lifting detector. and an operation regulating circuit that activates a boom extension regulating device, a boom hoisting/lowering regulating device, a boom hoisting/raising regulating device, and a hoisting regulating device of the lifting device when the lifting detector simultaneously outputs an output. Operation regulation device for aerial work vehicles equipped with