JPH0627464U - Fall prevention device for aerial work vehicles - Google Patents

Abstract

(57) [Summary] [Purpose] Automatically detects sudden bumps and bumps on the road surface to prevent rolling of aerial work vehicles. [Structure] The workbench 16 is moved to the chassis 1 by the lift mechanism 14.
In an aerial work vehicle that can be moved up and down on the work table 1,
An unevenness detection sensor 22 is provided which includes a sensor wheel 24 that is grounded and separated in conjunction with the lifting and lowering of 6 and can be vertically moved by being repulsed to the ground side, and a switch 26 that detects a constant vertical movement of the sensor wheel 24. A fall prevention device for aerial work vehicles.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a fall prevention device for an aerial work vehicle.

[0002]

[Prior art]

 There is an aerial work vehicle in which work can be performed at a high place by providing a work platform so that the work platform can be moved up and down on the chassis (for example, Japanese Patent Laid-Open No. 58-63697). In such an aerial platform vehicle, the higher the platform, the less stable it becomes. Therefore, the method is to detect the height of the worktable and limit the traveling speed according to the height.

[0003]

[Problems to be solved by the device]

 However, this is fine if the road surface is relatively flat, but it is extremely dangerous if there are steps. In particular, the pilot rides on a relatively high work platform and may not notice this. In such a case, the work platform may fall even if the work platform is low. The present invention solves such a problem and makes it possible to automatically detect sudden irregularities on the road surface.

[0004]

[Means for Solving the Problems]

 Under the above problems, the present invention is an aerial work vehicle in which a workbench is lifted on a chassis by a lift mechanism so that the workbench is grounded and separated in conjunction with the lifting and lowering of the workbench, and is repelled to the ground side. The present invention provides a fall prevention device for an aerial work vehicle, which is provided with an unevenness detection sensor including a sensor wheel that can move up and down and a switch that detects a constant up and down movement of the sensor wheel.

[0005]

[Action]

 By taking the above-mentioned means, the sensor detects that the sensor wheel goes down (or goes up) if there is unevenness on the road surface during work traveling with the work platform raised, and the switch detects this. When the vehicle is traveling at high speed with the workbench lowered, the sensor wheels are separated from the ground and do not interfere with traveling.

[0006]

【Example】

 1 and 2 are side views of an aerial work vehicle according to the present invention. The aerial work vehicle includes a crawler type traveling device 10 driven by a battery-powered motor or the like, and a crawler type work device. It comprises a chassis 12 supported by the traveling device 10 and a work platform 16 which is lifted up and down with respect to the chassis 12. Although the lift mechanism 14 has various structures, this embodiment shows a scissor link in which the X-shaped links 18 are stacked in several stages and expanded and contracted by the hydraulic cylinder 20.

The unevenness detection sensor 22 according to the present invention is provided in the above aerial work vehicle. Concavo-convex detection sensor 22 is composed of a sensor wheel 24 that comes into contact with and separates from the work table 16 as it moves up and down, and a switch 26 that detects a constant vertical movement of the sensor wheel 24. That is, an arm 30 that rotates up and down around the support shaft 28 is provided at the front (or rear) of the crawler type traveling device 10, the sensor wheel 24 is attached to the tip of this arm 30, and the arm 30 is formed. The switch 26 is kept in contact with the cam portion 32.

The above-mentioned sensor wheels 24 are designed to come into contact with and separate from each other in association with the lifting and lowering of the workbench 16. Although various structures can be considered for this structure, the structure using the hydraulic cylinder 36 is shown in this embodiment. That is, when the pull-up piece 38 is attached to the hydraulic cylinder 36, the hydraulic cylinder 36 is shortened and the arm 30 is pulled up by the pull-up piece 38, the sensor wheel 24 separates from the ground, and when extended, the arm 30 is grounded. I did so. Then, the switching of the direction switching valve that controls the hydraulic cylinder 36 and the switching of the direction switching valve that controls the hydraulic cylinder 20 of the lift mechanism 14 are linked. This system has the advantage that the height of the workbench 16 and the relationship when the sensor wheel 24 contacts the ground can be arbitrarily changed.

In addition, the arm 30 is biased by a spring 40 so as to rotate downward, and the sensor wheel 24 is elastically urged to the ground side. The sensor wheel 24 may be fixed to the arm 30 and its direction does not change, but it is more preferable that the sensor wheel 24 can rotate 360 ° with respect to the axis of the arm 30 (in the horizontal plane) ( Its structure is well known, so a detailed description is omitted here.)

As described above, during work traveling with the workbench 16 raised (the sensor wheels 24 are in contact with the ground), if there are unevenness 42 such as a step in front of the road, the sensor wheels 24 will fall into this (or (Riding up), the arm 30 rotates up and down to operate the switch 26. When the switch 26 is activated, appropriate measures such as stopping traveling are taken. Further, if the sensor wheel 24 can be turned 360 ° in the horizontal plane, this aerial work vehicle can change its direction minutely in the work place, so that it can roll smoothly even in such a case.

FIG. 3 is a side view of a main portion of another embodiment of the present invention. In this embodiment, the open spread of the X-shaped link 18 is detected by the potentiometer 44 and the height of the workbench 16 is increased. I try to determine the degree. Then, the traveling speed of the work vehicle (the rotational speed of the drive motor) is limited according to the output of the potentiometer 44. FIG. 4 is a graph showing the relationship between the traveling speed and the height of the workbench 16 (openness of the X-shaped link 18). In this way, the traveling speed is linearly increased as the workbench 16 is raised. It will also be possible to lower it. In this respect, conventionally, the speed was changed stepwise (mostly, two steps of high speed and low speed) according to the height of the workbench 16, but this is not efficient.

[0012]

[Effect of device]

 As described above, the present invention can automatically detect the unevenness associated with a fall simply by providing the unevenness detection sensor having a simple structure including the sensor wheel and the switch. Therefore, the safety of work can be secured. The sensor wheels that make up the unevenness sensor are separated from the ground when the vehicle is traveling at high speed with the workbench lowered, so they do not interfere with traveling.

[Brief description of drawings]

FIG. 1 is a side view of an aerial work vehicle showing an embodiment of the present invention.

FIG. 2 is a side view of an aerial work vehicle showing an embodiment of the present invention.

FIG. 3 is a side view of a main part of an aerial work vehicle showing another embodiment of the present invention.

FIG. 4 is a diagram showing a relationship between a traveling speed and a workbench height showing an effect of another embodiment of the present invention.

[Explanation of symbols]

 12 chassis 14 lift mechanism 16 workbench 22 unevenness detection sensor 24 sensor wheel 26 switch

Claims (2)

[Scope of utility model registration request] 1. In an aerial work vehicle in which a workbench is liftably mounted on a chassis, the workbench can be grounded and separated in conjunction with the lifting and lowering of the workbench, and can be vertically lifted by being repulsed to the ground side. An overturn prevention device for an aerial work vehicle, comprising an unevenness detection sensor comprising a sensor wheel and a switch for detecting a constant vertical movement of the sensor wheel. 2. The sensor wheel according to claim 1, wherein the sensor wheel is 36 in a horizontal plane.
A fall prevention device for aerial work vehicles that can turn 0 °.