JP2566345Y2 - Sub-boom for aerial work vehicles - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sub-boom of an aerial work vehicle, which is attached to a tip of a boom and used for lifting work.

[0002]

2. Description of the Related Art As shown in FIG. 4, an aerial work vehicle is provided with a boom 3 mounted on a revolving base 2 of a vehicle body 1 so as to be able to move up and down, expand and contract, and the like. 7 is attached. Conventionally, such an aerial work vehicle is used for wiring to a utility pole, mounting a transformer, and the like. When performing such work with an aerial work vehicle, it is often necessary to lift a wiring symmetric object, a transformer, or the like to a work position, that is, to a position near a work table. The sub boom 50 provided is also conventionally provided.

As shown in FIG. 4, a conventional sub-boom 50 is composed of an arm member 51 extending obliquely upward at the tip of the boom 3 and a winch 52 attached to the base of the arm member 51. Become. From the winch 52, the wire 53
Extend downward, and the hook 5 at the tip of the wire 53
4 and the object T to be lifted is hung. Note that the arm member 51 is detachable, and when the boom is stored, the arm member 51 is detached and stored so as not to be in the way.

[0004]

In the case of such a conventional sub-boom 50, the arm member must be removed each time the boom is stored, and the arm member must be reattached when the boom is to be used. There is a problem that the attaching / detaching work is troublesome. Further, since the arm member extends obliquely upward, its pocket space (a space located below the arm member; in FIG. 4, a triangular space below the arm member 51) is narrow. There are also problems. For this reason, there is a problem that if the object T to be lifted is lifted too much, the upper end may interfere with the lower surface of the arm member 51.

The present invention has been made in view of such a problem.
Provided is a sub-boom for aerial work vehicles that can be stored compactly with the sub-boom attached to the boom tip, does not require attachment or detachment of arm members when the boom is stored, and allows for a wider pocket. The purpose is to do.

[0006]

In order to achieve the above object, according to the present invention, a base member attached to the tip of a boom of an aerial work vehicle, a parallel link mechanism attached to the base member, An arm member supported by the base member via the parallel link mechanism and lifting means attached to the arm member constitute a sub-boom for aerial work vehicles. Then, among the first to fourth link members constituting the parallel link mechanism, a connection point between the first link member and the fourth link member is connected to the base member, and the parallel link mechanism is attached to the base member. A third link member located on the opposite side of the one link member is formed integrally with the arm member. Further, a first cylinder for swinging the first link member about the connection point and a second cylinder for swinging the fourth link member about the connection point are attached to the base member.

[0007]

In the sub-boom having such a structure, the first
When the first link member is swung by the cylinder, the third link member, that is, the arm member, located on the opposite side of the first link member, can be swung (up and down operation). Also,
When the fourth link member is swung by the second cylinder, the second and fourth link members are swung, and the third link member including the arm member can be moved in parallel between the working position and the storage position. . That is, the arm member can be translated from the storage position to the working position by the second cylinder via the parallel link mechanism.

[0008]

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 an aerial work vehicle having a sub-boom according to the present invention. This aerial work vehicle has a turntable 2 that can turn freely on a vehicle body 1, and a telescopic boom 3 is attached to the turntable 2 so as to be able to move up and down. The telescopic boom 3 comprises a telescopic (nested) telescopic base boom 3a, an intermediate boom 3b and a distal boom 3c.
It is pivoted through and is undulating. The telescopic boom 3 is telescopically operated by a telescopic cylinder (not shown) disposed therein, and is raised and lowered by a raising and lowering cylinder 4 disposed between the swivel base 2 and the base end boom 3a.

A support member 6 is attached to the distal end of the distal boom 3c so as to be pivotable up and down by a pin 3d. The support member 6 has a vertical post 6a, and a bracket 7a of a worktable 7 is rotatably attached to the vertical post 6a.
, So that it can be turned horizontally. Since the worker M rides on the work table 7, the work table 7 is always kept horizontal regardless of whether the boom 3 is up or down. For this reason, a leveling device including an upper leveling cylinder 5a and a lower leveling cylinder 5b is attached to this aerial work vehicle. As shown in FIG. 1, the upper leveling cylinder 5a is disposed between the distal end boom 3c and the support member 6, and the lower leveling cylinder 5b is disposed between the swivel base 2 and the proximal end boom 3a. I have. The oil chambers on the bottom side and the oil chambers on the rod side of these leveling cylinders 5a and 5b are communicated with each other. Is always kept horizontal. Outriggers 9 that extend at the time of work and support the vehicle body 1 are attached to four front, rear, left and right positions of the vehicle body 1.

On the other hand, a sub-boom 10 according to the present invention is also mounted on the vertical post 6a, and the structure of the sub-boom 10 will be described in detail with reference to FIGS. The sub-boom 10 has a base member 11 attached to the upper end surface of the vertical post 6a so as to be horizontally pivotable,
The parallel link mechanism 2 attached to the base member 11
0. The parallel link mechanism 20 includes first to fourth link members 21 to 24, and includes four connecting pins 20a.
As shown in the drawing, they are connected to each other so as to be freely rotatable by 20d to form a parallelogram. The first link member 21 and the third link member 23 are opposite sides, and the second link member 22 and the fourth link member 24 are opposite sides.

First link member 21 and fourth link member 24
Is connected to the base member 11, and the parallel link mechanism 20 is connected to the base member 11.
A first hydraulic cylinder 25 and a second hydraulic cylinder 27 are swingably attached to the base member 11. The piston 25a of the first hydraulic cylinder 25 is connected to the extension 21a of the first link member 21 by a pin 25b, and the piston 27a of the second hydraulic cylinder 27 is connected to the base of the fourth link member 24 by a pin 27b. ing.

The parallel link mechanism 20 constructed as described above
The third link member 23 is a member that protrudes largely outward from the connecting pins 20c and 20d, and thus forms an arm member. That is, in the present example, the third link member and the arm member are the same member, and therefore, the description will be given by giving the same number 23 to both. A winch 30 is attached to the rear end of the arm member 23, and a sheave 35 is rotatably attached to the front end. A wire 31 extending from the winch 30 is wrapped around the sheave 35, and the wire 31 hangs downward from the front end of the arm member 23,
A hook 32 is attached to the tip. For this reason, as shown in FIG.
, The lifting target T suspended on the hook 32 can be lifted.

The sub-boom 10 is retractable as described later, and FIGS. 1 and 2 show a state in which the sub-boom 10 is in a working position. At this time, the second and fourth link members 22 and 24 are substantially upright, and the arm member 23 extends substantially horizontally. For this reason, the space below the arm member 23, that is, the pocket space of the sub-boom 10 is wide, and even if the object T to be lifted is lifted as close as possible to the sheave 35, there is no fear that this will interfere with the arm member 23. Is easy to do. In addition, since the pocket space is large as described above, the lifting target T
Can be lifted.

When the piston 25a of the first hydraulic cylinder 25 is expanded and contracted in the state shown in FIG. 2, the first link member 21 is swung up and down around the connecting pin 20a, and the arm member is moved via the second link member 22. (Third link member) 23
Can be vertically swung (bent and stretched) around the connecting pin 20d. In the case of the sub boom 10 of the present example, the arm member 23 is operated by the expansion and contraction operation of the first hydraulic cylinder 25.
Can be swung up and down by 30 degrees each around the connecting pin 20d.

In the state shown in FIG. 2, the second hydraulic cylinder 27
When the piston 27a is extended, the fourth link member 24 is caused to fall rearward around the connection pin 20a.
At this time, the first link member 21 is connected to the first hydraulic cylinder 25
The second link member 22 is also laid down rearward around the connection pin 20b, and the arm member 23 constituting the third link member is oriented in the horizontal direction. 2nd and 4th as they are
The link members 22 and 24 are translated rearward and downward in accordance with the falling down. The piston 27 of the second hydraulic cylinder 27
a is fully extended, and the second and fourth link members 2
When the members 2 and 24 are turned down by about 90 degrees from the state shown in FIG. 2, the state shown in FIG. 3 is obtained, and the arm member 23 substantially overlaps with the second and fourth link members 22 and 24 and enters the retracted state. Note that the position of the arm member 23 at this time is referred to as a storage position. As can be seen from this, in the case of the sub-boom 10, the arm member 23 can be moved between the working position and the storage position by expanding and contracting the second hydraulic cylinder 27. That is, the sub-boom 10 can be stored while the sub-boom 10 is attached to the vertical post 6a.

Since the sub-boom 10 is used for wiring work or the like, the center portion 23a of the arm member 23, the second
Central portion 21a of link member 21 and fourth link member 2
The central portion 24a of the fourth member is made of an insulating material (for example, FRP) to achieve electrical insulation. Accordingly, even when the wire 31 or the object T to be lifted touches a live line during the lifting operation by the sub-boom 10, current is prevented from flowing to the work table 7 and the work table 7 It is possible to ensure the safety of the worker who has boarded.

[0017]

[Effects of the Invention] As described above, according to the present invention,
An arm member having lifting means is attached to the tip of the boom of the aerial work vehicle via a parallel link mechanism to form a sub-boom for the aerial work vehicle, and among the first to fourth link members constituting the parallel link mechanism A connection point between the first link member and the fourth link member is connected to the base member, and a third link member located on the opposite side of the first link member is formed integrally with the arm member. A first cylinder that swings the member about the connection point and a second cylinder that swings the fourth link member about the connection point are attached. Therefore, when the first link member is swung by the first cylinder, the third link member, that is, the arm member located on the opposite side of the first link member can be swung (up and down operation). Further, when the fourth link member is swung by the second cylinder, the third link member composed of the arm member is moved in parallel between the working position and the storage position, and the third link member is moved from the storage position without attaching / detaching the arm member. It can be easily translated to the working position. Further, in the state where the parallel link mechanism is located at the working position, the parallel link mechanism extends vertically, and the arm member extends substantially horizontally forward, so that the sub-boom has a large pocket space, and can lift a large object. Easy to do work.

[Brief description of the drawings]

FIG. 1 is a front view showing an aerial work vehicle equipped with a sub-boom according to the present invention.

FIG. 2 is a front view showing a state where the sub-boom is in a working position.

FIG. 3 is a front view showing a state where the sub-boom is in a storage position.

FIG. 4 is a front view showing a conventional aerial vehicle equipped with a sub-boom.

[Explanation of symbols]

 2 Swivel base 3 Telescopic boom 7 Workbench 10 Sub boom 11 Base member 20 Parallel link mechanism 23 Arm member 25, 27 Hydraulic cylinder 30 Winch 32 Hook 35 Sheave

Claims (1)

(57) [Scope of request for utility model registration] 1. An aerial work vehicle having a boom that can be raised and lowered freely on a vehicle body and a work table attached to the tip of the boom. A work vehicle sub-boom, a base member attached to a tip of the boom, a parallel link mechanism attached to the base member, an arm member supported by the base member via the parallel link mechanism, A lifting means attached to the arm member, wherein a connection point between the first link member and the fourth link member among the first to fourth link members constituting the parallel link mechanism is connected to the base member. A third link member located on the opposite side of the first link member is formed integrally with the arm member; and the base member has the first link member centered on the connection point. A sub-boom for an aerial work vehicle, wherein a first cylinder that swings the first link member and a second cylinder that swings the fourth link member around the connection point are attached.