JPH08151196A - Flexible-tip-type expansion boom - Google Patents

Abstract

PURPOSE: To obtain such a function as the tip of a boom can extend or contract and to use a working platform, which is attached to the tip of the boom, at once even from the stored position. CONSTITUTION: An expansion boom consists of a first boom member 42 and a second boom member 43, which is attached to the first boom member 42 in the longitudinal direction and in a freely expandable manner. The second boom member 43 is constituted of a base-end side part 44, which is connected to the first boom member 42 in the longitudinal direction and in a freely expandable manner, and a tip-end side part 45, which is connected to the tip end of the base-end side part 44 in a freely bendable manner. In addition, it is constituted that not only the base-end side part 44 but at least one part of the tip-end side part 45 can be stored within the first boom member 42, as the tip-end side part 45 is extended straight with respect to the base-end side part 44.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tip bending type telescopic boom which is capable of freely extending and contracting and bending and stretching the tip portion.

[0002]

2. Description of the Related Art A conventional tip bending type telescopic boom is attached to the vehicle body of an aerial work vehicle 100, for example, as shown in FIG. The telescopic boom includes a base end boom member 141 pivotably supported on a vehicle body, and the base end boom member 1
A telescopic portion configured in a telescope shape from an intermediate boom member 142 that is inserted into the intermediate boom 142 so as to be telescopically movable in the longitudinal direction, and a tip boom member 143 that is inserted into the intermediate boom 142 so as to be telescopically moved in the longitudinal direction. 104 and a bending boom (bending / extending portion) 105 pivotally connected to the tip of the tip boom member 143 so as to bend and extend in the vertical direction. At the tip of the bending boom 105, there is a work table 109 for a worker to board.
Are attached so that they are always horizontal via a leveling mechanism.

According to the aerial work vehicle 100 having such a telescopic boom, in addition to the movement of the workbench 109 in an arbitrary direction due to the ups and downs of the telescopic portion 104, the flexion and extension portion 10 is moved.
The workbench 109 can be moved up and down by the bending and stretching operation of 5, and the work can be performed efficiently. And
After the work is completed, the stretchable portion 104 and the bending / extending portion 105 cause the stretchable portion 104 to fully contract and lie down substantially horizontally as shown by an arrow A in FIG. It is stored with respect to the vehicle body so as to be folded downward.

[0004]

However, when the work is carried out by the aerial work vehicle having such a structure, first, the bending portion 105 is extended from the storage state to the outside as shown by the chain line in the drawing. There is a need. However, in order to extend the bending portion 105 with respect to the telescopic portion 104 and to extend the workbench 109 to the outside of the telescopic portion 104, as shown by an arrow B in FIG. First, the stretchable portion 104 needs to be raised to some extent so as not to interfere with.

As can be seen from this, in the aerial work vehicle configured as shown in FIG.
It is necessary to perform the raising operation (and the extension operation) of 04 and the bending operation of the outer side of the workbench 109, and there is a problem that the operations at the start of the work and the storage at the end are time-consuming. Furthermore, there is a restriction in the height direction, and the stretchable portion 1
In a place where 04 cannot be sufficiently raised, it is difficult to perform the bending and stretching operation of the telescopic portion 104 of the workbench 109 to the outside, and it may not be possible to perform work using this aerial work vehicle. There was a problem.

The present invention has been made in view of the above problems, and has a tip bending type expansion / contraction type having a tip bending / extending function, and a work table or the like attached to the tip can be used immediately even in a stored state. Aim to provide a boom.

[0007]

In order to achieve the above object, according to the present invention, a first boom member and a second boom member attached to the first boom member so as to be capable of extending and contracting in the longitudinal direction are expanded and contracted. A boom is constituted by a base end side portion that is connected to the first boom member in a longitudinal direction so that the second boom member can be expanded and contracted in a longitudinal direction, and a tip end side portion that is flexibly connected to a tip end of the base end side portion. Configure. Then, in a state where the distal end portion extends linearly with respect to the proximal end portion, not only the proximal end portion but also at least a part of the distal end portion can be stored in the first boom member. are doing.

The tip side portion can be constituted by a parallelogram link mechanism composed of a pair of link members, preferably upper and lower link members which are vertically spaced apart from each other. In this case, one of the link members is composed of a hollow member having a space extending in the longitudinal direction,
It is preferable that the other is composed of a rod member extending through this space, and a bending and stretching cylinder that bends and extends the tip end side portion with respect to the base end side portion is also arranged in this space.

It is to be noted that the above-mentioned telescopic boom with a tip bending type is provided on the vehicle body so that it can be raised and lowered, and a workbench is attached to the tip of the tip side portion of this telescopic boom via a leveling mechanism to construct an aerial work apparatus. can do. Here, in the case where the tip side portion is constituted by the parallelogram link mechanism as described above, the workbench can be attached to the tip end of the tip side portion via the leveling mechanism. Furthermore, if one of the link members is made of a hollow member, the cables and hoses that connect between the vehicle body side and the workbench should be placed through the space of the hollow member that constitutes this link mechanism. You can

[0010]

With such a tip bending / extending type telescopic boom and an aerial work apparatus, even when the second boom member is stored in the first boom member, the work attached to the tip of the second boom member is performed. The table etc. are ready for immediate use.
Therefore, it is possible to immediately start the work without elevating the elastic portion in advance, unlike the type in which the workbench or the like is attached to the tip of the elastic portion via the bending portion. Then, the first boom member is exposed until the tip side portion of the second boom member is exposed.
Only by extending the second boom with respect to the boom member, the tip end side portion can be flexed and extended freely, and efficient work in high places using this tip bending and extension function can be performed.

Further, when the tip side portion is constituted by a parallelogram link mechanism, one link member is constituted by a hollow member having a space extending in the longitudinal direction as described above, and the other link member is arranged in this space. If the rod member extends through the hollow member, the strength of the tip side portion can be increased by the hollow member. Further, it is possible to dispose a bending / stretching cylinder that bends / stretches the tip side portion in the space of the hollow member, and to dispose cables and hoses that connect between the vehicle body side and the workbench. Not only is it easy to arrange them, but the appearance is also good.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT A preferred embodiment of the present invention will be described below with reference to the drawings. FIG. 1 shows an aerial work vehicle equipped with a tip bending type telescopic boom according to the present invention. This aerial work vehicle 1 is configured with a truck as a base, and outrigger jacks 2 for supporting the vehicle body 1a by projecting to the side of the vehicle body 1a and supporting the vehicle body 1a at four locations on the front, rear, left, and right of the vehicle body 1a. Is attached (however, in the figure, only the left and right rear trigger jacks 2 are shown). At the rear part of the vehicle body 1a, a swivel base 3 that is capable of horizontally swiveling with respect to the vehicle body 1a is attached. The telescopic boom 4 is attached to the upper part of the swivel base 3.

The telescopic boom 4 includes a base end boom member 41 pivotably supported on the swivel base 3 and a base end boom 4 which is provided.
1. An intermediate boom member (“first boom member” in the claims) 42 that is inserted in the first boom 1 so as to be extendable and retractable in the longitudinal direction, and a tip boom member that is inserted in the intermediate boom 42 so as to be telescopically movable in the longitudinal direction. (“Second boom member” in the claims) 43 and a telescope. The hydraulic hoisting cylinder 5 is mounted between the base end boom member 41 and the swivel base 3, and the telescopic boom 4 is entirely hoisted and driven by the telescopic operation of the hoisting cylinder 5. Further, although not shown, in the telescopic boom 4, a first hydraulic telescopic cylinder that drives the intermediate boom member 42 to extend and retract with respect to the base boom member 41, and a tip boom member 43 extend and retract with respect to the intermediate boom member 42. A second hydraulic telescopic cylinder to be driven is incorporated. Therefore, the working oil can be supplied to both the telescopic cylinders to simultaneously expand and contract the intermediate boom member 42 and the tip boom member 43, while the working oil is supplied only to the second telescopic cylinder to supply the tip boom member 43.
It is also possible to make only the telescopic operation.

A portion (hereinafter, referred to as a base end side member) 44 from the middle portion in the longitudinal direction of the tip boom member 43 (hereinafter referred to as a base end side member) has a tubular shape having a rectangular cross section like the base end boom member 41 and the intermediate boom member 42. Is formed in. A portion 45 of the tip boom member 43 from the middle portion in the longitudinal direction to the tip side (hereinafter, referred to as a tip side member) 45 is composed of two sets of parallel links attached to the left and right of the base end side member 44. Only the left parallel link is shown in FIG.

This parallel link (that is, the tip side member 45)
As shown in detail in FIG. 2, the first link 4 has a base end portion pivotally supported on an upper portion of the base end side member 44 so as to be vertically swingable.
5a, a second link 45b whose base end is pivotally supported in the lower part of the base end side member 44 so as to be swingable in the vertical direction, and in the state where these are extended in parallel, the tip ends of these are vertically rocked. The boom head 46 is rotatably supported.
In addition, between the pin 47 that pivotally supports the second link 45b with respect to the base end side member 44 and the longitudinal intermediate portion of the first link 45a, the entire tip end side member 45 swings vertically (that is, bends and extends). A hydraulic bending cylinder 48 is attached.

At the tip of the boom head 46, a vertical post 6 is provided in the left-right direction in the figure (that is, the axial direction of the telescopic boom 4).
It is pivotally supported on. An upper leveling cylinder 7 a is attached between the upper portion of the vertical post 6 and the boom head 46. A closed hydraulic circuit is formed between the upper leveling cylinder 7a and a lower leveling cylinder 7b mounted between the proximal end of the proximal boom member 41 and the rear of the swivel base 3 as shown in FIG. ing. This hydraulic closed circuit extends the upper leveling cylinder 7a when the telescopic boom 4 is raised and the lower leveling cylinder 7b is contracted (which causes the vertical post 6 to swing to the left in the drawing), and the telescopic boom 4 When the lower leveling cylinder 7b is extended and the lower leveling cylinder 7b is extended, the upper leveling cylinder 7a is contracted (so that the vertical post 6 swings to the right in the figure).
a and 7b are connected. Therefore, the vertical post 6
Regardless of the undulating state of the telescopic boom 4, it is always maintained almost vertically.

Even if the tip side member 45 bends and extends due to the parallel linking action of the tip side member 45, the posture of the boom head 46 with respect to the telescopic boom 4 does not change (FIG. 2).
reference). Therefore, it can be said that the vertical post 6 is always maintained substantially vertically regardless of the undulating state and the bending state of the tip side member 45.

On the upper part of the vertical post 6, a work table bracket 8 is mounted which can swing horizontally around the vertical post 6. A workbench 9 is attached to the side surface of the workbench bracket 8. This workbench 9
An operator (not shown) can board the vehicle. Furthermore, on the upper part of the work table 9, the swivel operation of the swivel base 3 and the undulating operation / extension of the telescopic boom 4 (the intermediate / tip boom member 4) are performed.
Expansion and contraction of 2, 43 and expansion and contraction of the tip boom member 43 only)
An operation device 10 for controlling the operation, the bending operation of the tip boom 43, and the swing operation of the workbench 9 is attached. An operator who has boarded the workbench 9 can move the workbench 9 to an arbitrary height through the operation of the operation device 10 to perform a desired work at a high altitude. At this time, as shown by the arrow A in FIG. 1, the distal side member 45 may be projected from the intermediate boom member 42 while the telescopic boom 4 is being extended as a whole, and the bending function of the distal boom member 43 may be used. Even if there is not such a space, it is possible to extend only the tip boom member 43 to cause the tip side member 45 to project from the intermediate boom member 42 and use the bending and stretching function.

After the work is completed, the distal end side member 45 is made to extend in a straight line with respect to the proximal end side member 44,
Fully retract the telescopic boom 4. In this way, when it is extended straight, not only the base end side member 44 but also the front end side member 4
5 can also be stored in the intermediate boom member 42, as indicated by arrow B in the figure. After that, the telescopic boom 4 is horizontally laid down, and the swivel base 3 is further directed toward the front of the vehicle body 1a, whereby the telescopic boom 4 can be stored in the vehicle body 1a. The tip boom member 43 having a bending / extending function is housed in the intermediate boom member 42 except the boom head 46, and the retractable boom 4 is stored while the workbench 9 is positioned ahead of the retractable boom 4. Next, even if the place where the aerial work vehicle 1 is used does not have much room in height, there is no problem (for example, as in the conventional aerial work vehicle shown in FIG. The worker can board the work table 9 to perform the work (without the problem that the work cannot be sent to the other side).

In the above aerial work vehicle, the tip side member 4
Although 5 is composed of two rods extending vertically in parallel at a predetermined interval, the tip side member can be configured as shown in FIG. Note that, in FIG. 3, the same parts as those in the above embodiment will be described with the same reference numerals. The tip end side member 50 is composed of two vertical link members 51 and 55 that are pivotally connected to the base end side member 44 and extend in parallel with each other, and the boom head 46 is provided at the tip ends of the link members 51 and 55. Are linked together. As shown, the pivot points 51a, 51b, 55a at both ends of the link members 51, 55,
55b is located at the apex of the parallelogram, and the base end side member 44 (the tip end thereof), the upper and lower link members 51 and 55, and the boom head 46 constitute a parallelogram link mechanism.

The upper link member 51 is composed of a hollow member having a hollow rectangular cross section as shown in FIG.
A hollow space 52 extending in the longitudinal direction is formed therein. The lower link member 55 is composed of a solid rod member, and is disposed through the hollow space 52 of the upper link member 51. Both ends of the bending / extending cylinder 48 are pivotally connected at a pivot point 55b of the lower link member 55 and an intermediate point 51c of the upper link member, which is also disposed in the hollow space 52.

With such a structure, since the strength of the upper link member 51 having a rectangular hollow cross section is high, the strength of the distal end side member 50 can be increased and the appearance thereof can be improved. Furthermore, in this hollow space 52,
The hydraulic hoses 53 that connect the vehicle body side to the workbench side and the cables 54 (optical cables, electric cables, etc.) also have a hollow space 5
Since they can be arranged through two, they can be arranged easily.

Although the tip bending type telescopic boom of the above-mentioned embodiment is a three-stage telescopic boom composed of three boom members, the telescopic boom of the present invention is not limited to this, and two-stage or four-stage telescopic booms.
It may be a telescopic boom such as a step. Further, although the tip side portion in the above embodiment has a parallel link structure that can swing up and down, the structure and bending direction of the tip side portion in the telescopic boom of the present invention are not limited to this.
The bending and stretching driving method is not limited to the hydraulic cylinder as in the above embodiment.

[0024]

As described above, in the tip bending / extending type telescopic boom of the present invention, even when the second boom member is stored in the first boom member, the second boom member is attached to the tip end of the second boom member. The workbench etc. are ready for immediate use. Therefore, it is possible to immediately start the work without elevating the elastic portion in advance, unlike the type in which the workbench or the like is attached to the tip of the elastic portion via the bending portion. Then, only by extending the second boom with respect to the first boom member until the tip side portion of the second boom member is exposed, the tip side portion can be flexed and extended freely. It is possible to carry out work in high places, etc.

Further, when the tip side portion is constituted by a parallelogram link mechanism, one link member is constituted by a hollow member having a space extending in the longitudinal direction as described above, and the other link member is in this space. If the rod member extends through the hollow member, the strength of the tip side portion can be increased by the hollow member. Further, it is possible to dispose a bending / stretching cylinder that bends / stretches the tip side portion in the space of the hollow member, and to dispose cables and hoses that connect between the vehicle body side and the workbench. In addition to facilitating the disposition of these, the appearance can be improved.

[Brief description of drawings]

FIG. 1 is a front view of an aerial worker equipped with a telescopic boom with a tip bending type according to the present invention.

FIG. 2 is a partially enlarged view of the telescopic boom.

FIG. 3 is a front view showing another example of the tip bending type telescopic boom according to the present invention.

FIG. 4 is a cross-sectional view showing the telescopic boom along the arrow III-III in FIG.

FIG. 5 is a front view of a conventional aerial work vehicle.

[Explanation of symbols]

 1 Aerial work vehicle 4 Telescopic boom 9 Workbench 42 Intermediate boom member (first boom member) 43 Tip boom member (second boom member)

Claims (3)

[Claims] 1. A telescopic boom having a first boom member and a second boom member attached to the first boom member so as to be telescopically movable in the longitudinal direction, wherein the second boom member is the first boom member. 1 A base end side portion that is connected to the boom member in a longitudinally expandable and contractible manner, and a tip end side portion that is flexibly connected to the tip of the base end side portion, and the tip end side portion is the base end side. A tip bending type telescopic boom, wherein the base end side portion and at least a part of the tip end side portion can be stored in the first boom member in a state of linearly extending with respect to the portion. . 2. The tip flexion and extension according to claim 1, wherein the tip end side portion is constituted by a parallelogram link mechanism composed of upper and lower link members which are vertically spaced apart from each other. Type telescopic boom. 3. The tip end side portion is formed of a parallelogram link mechanism including a pair of link members, one of the link members is formed of a hollow member having a space extending in the boom axis direction, and the other of the links is formed. A bending / stretching cylinder is provided in the space of the one link member, the member being a rod member extending through the space of the one link member, and the bending / stretching cylinder bending and stretching the distal end side portion with respect to the base end side portion. The distal bending-type telescopic boom according to claim 1, wherein the telescopic boom is a telescopic boom.