JPS6132954Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a fall warning device for a vehicle having a boom, such as a truck with a crane.

Generally, in a crane vehicle, for example, a crane vehicle 1 with a loading platform as shown in FIG. 1, when performing crane work by raising and lowering the telescopic boom 2, the left and right stabilizing legs 3 are extended to prevent overturning. Not only when lifting a load above the limit, but also when the stabilizing legs cannot be fully extended on soft ground or in a narrow space, there is a risk of overturning even under a load below the limit. For this reason, as a means for detecting lifting of the stabilizing leg and issuing an alarm, for example, a limit switch is provided at the end of the stabilizing leg outer cylinder attached to the vehicle body, and the switch is slid inside the outer cylinder and has a jack at the tip. A method has also been attempted in which the limit switch is set opposite to the inner cylinder and activated by the change in the gap between the end of the outer cylinder and the inner cylinder due to lifting of the jack. It is switched on or off when the alarm is triggered, so by the time the alarm is triggered, the person is already floating, which can sometimes lead to a fall. For this reason, attempts have been made to quantitatively detect changes in hydraulic pressure within the stabilizing leg actuating cylinder as other fall warning means, but these have the drawback of being complicated and expensive circuits.

This invention was made in view of these points,
A strain detection member is installed between the piston and the piston rod of the jack cylinder, and the reaction force of the stabilizing leg is directly and quantitatively detected by the member. A conduit is inserted through the conduit, and using this conduit, the conductive wire connected to the detection member is pulled out to the outside without interfering with the expansion and contraction of the stabilizing leg and without damaging the airtightness inside the cylinder. It is an object of the present invention to provide a fall warning device that can be easily installed and removed, thereby solving the above-mentioned drawbacks.

EMBODIMENT OF THE INVENTION Hereinafter, the structure of this invention will be explained about an Example based on drawing.

In FIG. 2, reference numeral 5 denotes a jack cylinder of the stabilizing leg 3 of the vehicle 1 shown in FIG. This jack cylinder 5 consists of a cylinder tube 7 fixed to the tip of an inner tube 6 which is slidably fitted into an outer tube (not shown) of the stabilizing leg 3, and a rod cover 8 attached to the lower end of the cylinder tube. The piston rod 10 is mainly composed of a piston rod 10 that is slidably penetrated through the piston rod, and a piston 11 that is slidably inserted into the piston rod 10.
and a rod head 1 welded to the upper end of the main body 13.
It consists of 4. The rod head 14 has a large diameter base 15, an intermediate part 16, and a small diameter part 17 with different diameters.
The inner hole of the piston 11 has a stepped portion 20 as a stepped hole that fits into the intermediate portion 16 and the small diameter portion 17. A slight gap is provided between the lower surface and the base 15, and the nut 22 is attached to the small diameter portion 17.
An oil chamber 24 is formed between the upper surface of the piston 11 and the cylinder head 23.

25 is a strain detection member that detects the pressure between the piston 11 and the piston rod 10, that is, the reaction force of the piston rod 10, and is located between the stepped portion 20 provided in the piston inner hole and the upper stepped portion 18 of the rod head 14. It can be removably inserted into the. The strain detection member 25
is a load cell that converts applied pressure into electric resistance, for example, and the rod head 14 has a communication hole 28 connected to the inner hole 27 of the rod body 13 for drawing out a conductor 26 connected to the member 25. do.

30 is the cylinder head 23 and the rod head 1
A conduit that penetrates through the rod body 13 and protrudes for a required length into the inner hole 27 of the rod body 13, and is removably attached to the upper surface of the cylinder head 23 by sandwiching the packing 32 with a flange 31 attached to the upper end.
4 is provided with a gasket 33 for preventing oil leakage, and the conduit 30
is slidably inserted into the conduit 30, and the conductive wire 26 is drawn out through the inner hole of the conduit 30.

The conducting wire 26 is connected to an electric quantity converting device 35, and is connected to the piston rod 10 in the strain detecting member 25.
The change in electrical resistance corresponding to the reaction force generated at When the amount decreases and reaches the fall danger area, alarm buzzer 3 will sound.
6 is activated. In this case, a compressive load is applied to the strain detection member 25 by tightening the nut 22, but the amount of strain at that time is used as a reference point, and the fall danger area is defined as a point slightly before the reaction force of the stabilizing leg decreases to the reference point. As soon as the area is reached, the alarm buzzer 3
Adjust so that 6 is activated. It is preferable that the electric quantity converter 35 is linked with a hydraulic pump for operating the crane, so that a warning buzzer is activated until the stabilizing leg is installed, thereby preventing forgetting to install the stabilizing leg.

Further, in the figure, 40, 41, and 42 are gaskets for preventing pressure leakage.

As described above, according to the present invention, the reaction force generated on the stabilizing leg during crane work is directly detected using the strain detection member, so the reaction force can be quantitatively detected and the operator can avoid falling. It is possible to know how much margin there is until reaching the danger zone, and a warning is automatically issued when the danger zone is reached, thereby preventing a fall accident. However, in the case of the present invention, since the strain detection member is located between the piston rod and the piston and is not exposed to the outside (atmosphere), its damage or performance deterioration is reduced, and the reliability of the fall alarm system is improved. Improved durability, and
A conduit passing through the cylinder and piston rod is provided as a means for drawing out the conductor for the strain detection member 25, and the conduit is drawn out through the inner hole of the conduit, so that it does not interfere with the expansion and contraction of the stabilizing leg and is separated from the oil chamber. Therefore, the airtightness of the oil chamber is not impaired, and the strain detection member including the conductive wire can be easily removed, maintained, and inspected.

[Brief explanation of drawings]

The drawings show an embodiment of the present invention, and FIG. 1 is a side view of a crane tooth with a loading platform, and FIG. 2 is a longitudinal sectional view of the main part. 1... Crane truck with loading platform, 2... Telescopic boom,
3...Stabilizing leg, 5...Jet cylinder, 7...
Cylinder tube, 10...Piston rod, 1
1... Piston, 25... Strain detection member, 30...
conduit.

Claims (1)

[Scope of utility model registration request] In a vehicle having a boom having telescopic stabilizing legs mounted on the vehicle body with a jack cylinder, a strain detection member is removably disposed between a piston rod and a piston of the jack cylinder, and An overturning vehicle having a boom, characterized in that a conduit connecting the cylinder tube and the piston rod is inserted into the Tsuki cylinder, and the signal from the strain detection member can be conducted to the outside using the conduit. Alarm device.