JP2548983Y2 - Work range control device for bending and aerial work platforms - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bending and stretching type aerial work vehicle having a bending and stretching boom which can be freely bent and stretched via a bending portion on a vehicle body, and a worktable attached to the tip of the bending and boom.

[0002]

2. Description of the Related Art There is a problem in an aerial work vehicle having a work table attached to the tip of a boom that the moment applied to the vehicle body increases in accordance with the boom undulation, expansion and contraction operation, etc., and the support of the vehicle body becomes unstable. . For this reason, a worktable movement allowable range is set in advance so as to suppress this moment within a predetermined value, and the worktable restricts the operation of the boom beyond this range, and the body support during the work. It is well known in the art to prevent from becoming unstable. Here, in the case of an aerial work vehicle in which one boom member that can be raised and contracted is mounted on the vehicle body, and a work table is mounted on the tip of the boom member, the vehicle body corresponds to the position of the work table. Since the moment applied to the work table is determined, there is no problem even if the work range is restricted based on the movement allowable range of the work table as described above.

[0003]

However, a bending / extending boom composed of a plurality of boom members which are flexibly connected to each other via a bending portion is mounted on a vehicle body, and a work table is mounted at a tip of the bending / extending boom. In the case of a bending and stretching type aerial work vehicle composed of
Since it does not correspond only to the position of the worktable, there is a problem that accurate regulation cannot be performed only by controlling the work range based on the position of the worktable.

[0004] As an aerial work vehicle, for example, as shown in FIG. 4, a bending / extending boom composed of a base end boom member 53 and a distal end boom member 54 flexibly connected at a bending portion 55 is mounted on a vehicle body 51, and a distal end boom is provided. A bending and stretching type aerial work vehicle having a worktable 56 provided at the tip of a member 54 is shown. Conventionally, the moment in the direction indicated by arrow B due to the load or the like acting on the worktable 56 has been a problem.
The movement allowable range M3 of the work table 56 is set so that this moment does not become excessive, and the movement range of the work table 56 is regulated based on this range M3. Therefore, the worktable 5
The limit line M3 of the movement allowable range of No. 6 is set on the left side of the vehicle body in FIG. 4, and the operation of the bending and stretching boom that moves the work table 56 to the left side beyond this limit is restricted. .

However, in the case of a bending and stretching type aerial work vehicle,
As shown in FIG. 4, when the proximal boom 53 is extended and the distal boom 54 is reduced, these booms 53, 54
As shown by arrow A, the moment acting on the vehicle body due to its own weight is in the opposite direction to the moment acting by the load on the worktable 56, and the moment indicated by arrow A becomes excessively large and the vehicle body support becomes unstable. There is a problem that there is. That is, in the case of the bending and stretching type aerial work vehicle, even when the work table 56 is within the movement permission range M3, the vehicle body support may be unstable, and only by regulating the movement range of the work table, an accurate moment can be obtained. There is a problem that regulation cannot be performed.

The present invention has been made in view of such a problem.
Exact work range regulation for bending and stretching aerial work vehicles,
It is an object of the present invention to provide a work range control device that does not have a possibility that the vehicle body support becomes unstable during work.

[0007]

In order to achieve the above object, in the present invention, the elevation angle, flexion / extension angle and extension / retraction length of the flexion / extension boom are detected, and the position of the distal bending portion of the proximal end boom member and the flexion / extension boom are detected. Position detecting means for detecting the position of the workbench attached to the distal end, and comparing both positions detected by the position detecting means with a preset base boom tip movement permission range and a worktable movement permission range, respectively; Boom operation restricting means for restricting the operation of the bending / extension boom such that the distal bending portion of the end boom exceeds the permissible range of movement of the base boom tip and the operation of the bending / extending boom such that the worktable exceeds the permissible range of movement of the workbench. To form a work range control device.

[0008]

In the case where the working range restricting device having such a configuration is used, a moment (moment indicated by an arrow B in FIG. 4) acting by the load of the worktable in accordance with the operation of the bending / extending boom.
Regarding the above, the operation of the bending / extension boom is restricted so that the worktable does not move beyond the worktable movement allowable range, thereby preventing the worktable from becoming excessively large. On the other hand, the moment in the opposite direction (moment indicated by arrow A in FIG. 4)
With regard to (2), by restricting the operation of the bending / extending boom so that the distal bending portion of the proximal end boom does not move beyond the allowable range of the distal end movement, the excessive bending can be suppressed.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows an example of a bending and stretching type aerial work vehicle equipped with a work range control device according to the present invention. This aerial work vehicle has a swivel 3 on a vehicle body 1 so as to be freely rotatable. A base boom 4 is attached to the swivel 3 so as to be able to move up and down. The end boom 5 is freely attached, and a work table 7 is attached to the end of the end boom 5. The bending / extension boom 10 is constituted by the base end boom 4 and the distal end boom 5 connected by the bending pin 6 in this manner. Outrigger jacks 2 are provided at four front, rear, left and right sides of the vehicle body 1 to extend downward during operation and support the vehicle body 1.

The base end boom 4 can be raised and lowered by a raising / lowering cylinder 4a, and the angle between the base end boom 4 and the horizontal plane is referred to as a raising / lowering angle α. The distal boom 5 is freely bendable and extendable with respect to the base end boom 4 by a bending and stretching cylinder 5a, and an angle formed by the two booms 4 and 5 is referred to as a bending and stretching angle β (or a scissor angle). Each of the booms 4 and 5 is nested, and can be extended and contracted by a built-in telescopic cylinder (not shown). The work table 7 is designed to be loaded with an operator, and is attached to the end of the tip boom 5 via a leveling mechanism (not shown). It is always kept horizontal.

When performing work at a high place, after the worker gets on the work table 7, the worker operates the operation lever and the like provided on the work table 7 to control the turning of the turn table 3 and the base end boom. The operation of the bending / extension boom 10 is controlled by controlling the undulation and extension / contraction of the boom 4 and the bending / extension and extension / contraction of the tip boom 5 to move the work table 7 to a predetermined height. At this time, the swing control of the swivel base 3 is performed by controlling the operation of a swing motor (not shown), and the up / down and extension / retraction control of the base end boom 4 and the bending / extension and extension / retraction control of the distal end boom 5 control the operation of each hydraulic cylinder. Controlled and done. The operation of the hydraulic actuators such as the hydraulic motor and the hydraulic cylinder is controlled by an operation control valve, and the operation of the operation control valve is controlled based on the operation of an operation lever and the like.

FIG. 2 schematically shows an operation control device of the bending / extension boom 10 by controlling the operation of each actuator. The operation signal of the operation lever 21 is transmitted to the controller 22.
And is converted into a valve control signal, and this valve control signal is sent to the operation control valve 26. The operation control valve 26 is a valve for controlling the supply of the hydraulic oil from the hydraulic pump 25 to the hydraulic actuator 27. The operation control valve 26 performs the hydraulic supply control based on a valve control signal, and controls each hydraulic actuator 27 to operate the operation lever 21. Actuated accordingly
The operation of the bending / extension boom 10 is controlled.

However, a control signal from the moment limiter ML is also input to the controller 22. When the control signal is input, the controller 22 operates the hydraulic actuator regardless of the operation signal from the operation lever 21. , And a predetermined operation of the bending / extension boom 10 (operation in a direction to destabilize the vehicle body support) is restricted. The aerial work vehicle includes an elevation angle sensor 11 and a proximal end boom length sensor 12 for detecting an elevation angle and an extension / retraction amount of the proximal end boom 4, a flexion / extension angle sensor 13 for detecting a flexion / extension angle and an extension / contraction amount of the distal end boom 5, and A tip boom length sensor 14 and a turning angle sensor 15 for detecting the turning angle of the turntable 3 are attached, and detection signals from these sensors are input to a moment limiter ML.

The moment limiter ML receives the detection signals from the five sensors, and obtains the position of the tip bending pin 6 of the base boom 4 and the position of the front lower end point 7a of the worktable 7 by position detecting means 16; A memory 17 in which a base boom tip movement permission range and a worktable movement permission range are preset and stored;
The two positions detected by the position detecting means 16 are compared with the two movement permitted ranges, and the controller 2
2 for controlling the boom operation.

In the memory 17, a plurality of base boom tip movement permission ranges and a work table movement permission range are set and stored corresponding to the turning position of the bending / extension boom 10. This is because the allowable value of the moment applied to the vehicle body is outrigger jack 2.
This is because the allowable value of this moment differs depending on the turning position of the bending / extension boom 10. For this reason, the detection signal of the swivel angle sensor 15 is input to the memory 17, and the swivel angle of the swivel 3 at that time, that is, the base boom tip movement allowable range and the workbench move corresponding to the swivel position of the bending and extending boom 10 The permitted range is sent to the boom operation restricting means 18.

The base boom tip movement permission range and the worktable movement permission range are the ranges indicated by lines M1 and M2 in FIG. The boom operation restricting means 18 determines whether or not the position of the distal bending pin 6 of the distal boom 4 detected by the position detecting means 16 is within the allowable range of the proximal boom distal end movement indicated by the line M1 (the left side of the line M1). And the position of the front lower end point 7a of the worktable 7 is indicated by a line M2.
It is determined whether or not it is within the workbench movement permitted range (whether or not it is on the right side of the line M2). Then, when it is determined that the tip bending pin 6 has reached the line M1 or that the front lower end point 7a of the worktable 7 has reached the line M2, a regulation signal is output to the controller 22.

This regulation signal is obtained when the tip bending pin 6 is connected to the line M1.
Is determined, the bending of the bending / extending boom 10 such that the tip bending pin 6 moves to the right beyond the line M1 (moves beyond the allowable range of movement of the base boom tip). This signal is a signal for restricting the operation, and when it is determined that the front lower end point 7a of the worktable 7 has reached the line M2,
This is a signal that regulates the operation of the bending / extending boom 10 such that the front lower end point 7a moves to the left beyond the line M2 (moves beyond the worktable movement allowable range). In this manner, if the regulation ranges indicated by the lines M1 and M2 are provided and regulated, the instability of the vehicle body support due to the moment in the direction indicated by the arrow A in FIG. Both can be avoided.

In the above example, the bending / extension boom 10 connected by one bending pin 6 has been described, but the device of the present invention is not limited to this. For example, FIG.
As shown in the figure, a proximal end boom 34, an intermediate boom 35, which is sequentially connected to bend and extend by two bending pins 36, 38,
A bending / extension boom is constituted by the distal end boom 37, and the base end boom 34 is attached to the swivel 3 so as to be able to move up and down, and a working table 39 is attached to the distal end of the distal end boom 37 to form a bending / extension type work vehicle. Can be. Also in this case, similarly to the above, the bending pin 36 at the distal end of the proximal boom 34 is used.
Is positioned within the allowable range of movement of the distal end of the base boom indicated by the line M1 and the lower end point 39a of the workbench 39 is positioned within the allowable range of movement of the workbench indicated by the line M2. You.

In the above example, the worktable movement allowable range is set on the basis of the front lower end point of the worktable. However, this range may be set on the basis of any part of the worktable. That is. Similarly, the base boom tip movement permission range may be set based on any part of the tip of the base boom.

[0020]

[Effects of the Invention] As described above, according to the present invention,
Position detecting means for detecting the angle of undulation of the bending / extension boom, bending / extension angle, and extension / contraction length, and detecting the position of the distal bending portion of the base boom member and the position of the work table attached to the tip of the bending / boom, The detected positions are compared to the preset allowable range of the base boom tip movement and the allowable range of the platform movement, respectively, and the bending / extension boom is operated so that the tip bending portion of the base boom exceeds the range allowed for the base boom tip movement. And a boom operation restricting means for restricting the operation of the bending / extending boom such that the work table exceeds the work table movement allowable range, and constitutes a work range restricting device. For this reason, if this work range restricting device is used, the moment (moment indicated by arrow B in FIG. 1) acting on the work table due to the operation of the bending / extending boom is such that the work table exceeds the work table movement allowable range. By restricting the operation of the bending and stretching boom so that it does not move, this is suppressed from becoming excessive,
On the other hand, the moment in the opposite direction (arrow A in FIG. 1)
(Moment indicated by), by restricting the operation of the bending and extension boom so that the distal bending portion of the base boom does not move beyond the allowable movement range of the distal end, it is possible to prevent the bending of the bending boom from becoming excessive. Regardless, the vehicle body can always be stably supported.

[Brief description of the drawings]

FIG. 1 is a front view showing a bending and stretching type aerial work vehicle having a working range control device according to the present invention and a movement allowable range of a bending and stretching boom.

FIG. 2 is a block diagram showing the work range restricting device and an operation control device of a bending / extending boom.

FIG. 3 is a front view showing another example of the bending and stretching type aerial work vehicle having the work range restricting device according to the present invention;

FIG. 4 is a front view showing a bending and stretching type aerial work vehicle having a conventional work range control device.

[Explanation of symbols]

 2 Outrigger jack 3 Swivel base 4 Base end boom 5 Tip boom 6 Refraction pin 7 Workbench 21 Operating lever

 ──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A 2-129398 (JP, U) JP-A 63-154600 (JP, U) JP-A 63-157097 (JP, U)

Claims (1)

(57) [Scope of request for utility model registration] 1. A bending / extending boom having at least one bending portion is mounted on a vehicle body, and a work table is provided at a tip of the bending / extending boom, and the bending / extending boom is freely bent and extended via the bending portion. A bending and stretching type high-altitude work comprising a plurality of connected boom members, at least a base end boom member of these boom members is extendable and retractable, and the base end boom member is attached to the vehicle body so as to be able to move up and down. A work range control device for a vehicle, comprising: detecting an undulation angle, a bending / extension angle, and an extension / contraction length of the bending / extension boom,
Position detecting means for detecting the position of the bending portion of the distal end of the base end boom member and the position of the work table; and The operation of the bending / extending boom such that the distal bending portion of the base boom exceeds the base boom tip movement permission range and the work table exceeds the work table movement permission range, as compared with the table movement permission range. And a boom operation restricting means for restricting operation of the bending / extension boom.