JP2002104792A - High work equipment - Google Patents

Abstract

(57) [Problem] To provide a leveling mechanism that is lightweight and compact in an aerial work apparatus in which a workbench is attached to the tip of a boom that performs an up / down operation. A link member (65) and a piston rod (62) of a leveling cylinder (60) are pivotally connected to the tip of a boom (5) that can freely move up and down with respect to a base in a vertical plane. And the cylinder body 61 of the leveling cylinder are pivotably connected in a vertical plane to form a leveling mechanism 6. And cylinder body 6
The work table 8 is attached to the boom 5 via a swing mechanism 7 and the leveling cylinder 60 is extended and retracted, so that the work table 8 is swingably disposed in a vertical plane with respect to the boom 5 so that the high work equipment Is configured.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a boom that can move up and down on a base in a vertical plane, a leveling mechanism attached to the tip of the boom, and a boom mounted on the tip of the boom via the leveling mechanism. And an aerial work apparatus having an attached work table.

[0002]

2. Description of the Related Art As such an aerial work apparatus, for example, there is an aerial work vehicle equipped with an aerial work apparatus on a vehicle body. The aerial work vehicle is constructed by disposing a boom that can swing, raise and lower, and expand and contract on the body of a truck or the like that can travel freely, and attaches a workbench on which the operator rides to the tip of this boom. You. A boom operating device that controls the operation of the boom is provided on the workbench, and a worker who rides on the workbench operates the boom operating device so that the boom can be turned, raised and lowered, extended and contracted, and the like. The work table is moved to a desired high place to perform high place work.

In an aerial work vehicle having such a boom, the work platform is tilted irrespective of the boom angle so that the work table does not tilt when the boom is raised and lowered to change the boom angle. A leveling mechanism is provided to keep the floor of the table horizontal at all times. As shown in FIG. 6, the leveling mechanism includes a vertical post 96 pivotally connected to a distal end of a boom 95 in a vertical plane (in the plane of the boom) and a vertical post 96. And a leveling cylinder 94 which is provided between the swinging end and the boom tip and is swingably connected to each other in a vertical plane.

When the boom is raised and lowered, hydraulic pressure is supplied to the rod-side oil chamber or the bottom-side oil chamber of the leveling cylinder 94 to extend and contract the cylinder, thereby swinging the vertical post within the plane of the undulation angle. By moving the vertical post 96, the standing portion of the vertical post 96 operates so as to maintain the vertical state at all times. The work table 98 is mounted on a vertical portion of the vertical post 96 via a swing arm 97 so as to be horizontally pivotable. For this reason, the floor surface of the work table 98 is always kept horizontal regardless of the up-and-down angle of the boom 95 and the swing angle position of the work table.

[0005]

However, in the conventional leveling mechanism as described above, since the leveling cylinder is disposed so as to be surrounded by the end of the boom, there are the following problems. .

First, since the leveling cylinder is disposed toward the base end of the boom, it is necessary to avoid interference with a telescopic cylinder which is provided inside the boom and operates to extend and retract the boom. For this reason, it is necessary to provide a leveling cylinder arrangement part of a fixed length in the base end direction of the boom at the boom distal end, which causes a problem that the total shrinkage of the boom is enlarged or the total amount of extension of the boom is limited. was there.
Further, if the two cylinders are arranged vertically in parallel in order to avoid interference, it is necessary to make the end of the boom thick, which causes a problem that the weight of the entire boom increases and the workability is deteriorated. Was.

Second, the vertical post needs to be swung in the same angle range as the boom up / down angle range, and the leveling cylinder also needs to have a corresponding expansion / contraction length and swing angle. At this time, it is necessary to provide a slot-shaped opening in the lower surface of the boom tip to prevent the leveling cylinder from coming into contact with the boom tip at the maximum elevation angle of the boom after making the tip boom thin. Occurs. This complicates the configuration of the boom tip, and also has the problem of increasing the weight of the boom tip because the opening is provided while maintaining the strength of the boom tip.

Third, since it is necessary to swing the vertical post in the same angle range as the boom undulation angle range as described above,
To prevent the boom tip from contacting the vertical post at the maximum elevation angle of the boom, increase the length of the swing arm from the pivot pin of the vertical post to the swing end, and attach this arm end to the boom. It is necessary to dispose it so that it protrudes from the tip. Therefore, the distance between the workbench and the vertical post according to the range of the boom angle (arm length of the swing arm)
In order to prevent the swinging end from protruding below the boom, it is necessary to offset the pivot pin toward the upper end of the boom. There is a problem that the structure of the part is complicated, which causes an increase in weight.

Further, since the leveling cylinder is disposed inside the boom tip so that the outer periphery of the leveling cylinder is covered by the boom, there is a problem that maintenance of the cylinder is difficult.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and solves the above-mentioned problems to realize a lightweight and compact leveling mechanism, and further improves workability and maintainability. It is an object of the present invention to provide a working device at height.

[0011]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides a boom mounted on a base and movable up and down at least in a vertical plane, and a leveling mechanism provided at a tip end of the boom. And a work table attached to the end of the boom via a leveling mechanism. In addition, the leveling mechanism of the present invention includes a linking member and a leveling cylinder, one end of which is pivotally connected to the end of the boom in a vertical plane and the cylinder body of the leveling cylinder is connected to the other end of the linking member. The piston rod is pivotally connected to the tip of the boom in a vertical plane so as to swing freely in a vertical plane.
The work table is attached to the cylinder body and is arranged to be swingable in a vertical plane with respect to the boom by extending and retracting the leveling cylinder, thereby constituting a high-place work device.

In the above configuration, the leveling cylinder does not swing the vertical post in accordance with the boom up / down angle, but the leveling cylinder itself swings in the vertical plane (in the up / down angle plane) in accordance with the boom up / down angle. Then, the work table attached to the cylinder body is directly swung. That is,
The leveling cylinder according to the present invention itself has the functions of both the conventional vertical post and leveling cylinder. Therefore, there is no need to provide a cylinder disposition portion extending in the proximal direction inside the boom, and
Since there is no swinging end protruding from the boom tip, the boom tip can be configured to be lightweight and compact with a simple configuration, and the maintainability can be greatly improved.

The cylinder body is provided with a oscillating mechanism which is arranged coaxially with the telescopic axis of the leveling cylinder and is rotatable about the telescopic axis with respect to the cylinder body. The high work device may be configured to be attached to the cylinder body via the. In the configuration of the invention described above, since there is no swinging end of the vertical post in the related art, it is not necessary to provide a long swing arm between the leveling cylinder having the function of the vertical post and the worktable. Therefore, by providing the swing mechanism as in the present configuration, the swing mechanism can be configured to be extremely lightweight and compact.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below with reference to the drawings. As a preferred embodiment of the aerial work apparatus according to the present invention, an aerial work vehicle having a boom on a vehicle body is shown in FIG. The aerial work vehicle 1 is constructed on the basis of a truck chassis. The aerial work vehicle 1 has a driving cabin 2a and can be turned horizontally on the car body 2 by operating a turning motor 11 on the car body 2. A swing table 4 is provided, and a boom 5 is pivotally connected to the upper end of the swing table 4 so as to be able to move up and down in a vertical plane with respect to the vehicle body 2 by the expansion and contraction operation of an up and down cylinder 12.

The boom 5 includes a base boom 5a pivotally attached to the upper end of the swivel base 4, an intermediate boom 5b and a distal boom 5 which are sequentially slidably inserted into the base boom in a telescopic manner.
The intermediate boom 5b and the distal end boom 5c can be extended and retracted with respect to the proximal end boom 5a by extending and retracting an extendable cylinder 13 disposed inside the boom 5. A worktable 8 is attached to the distal end of the tip boom 5c via a leveling mechanism 6 and a swing mechanism 7, which will be described in detail later.
The floor surface of the boom 5 is always kept horizontal irrespective of the up-and-down angle of the boom 5 by the action of the boom 5, and the swinging mechanism 7 is operated so as to be horizontally pivotable with respect to the boom tip.

The boom 5 is raised and lowered on the front, rear, left and right sides of the vehicle body 2,
In order to stably support the vehicle body 2 against the overturning moment that acts on the vehicle body 2 when the vehicle is extended or the like to try to overturn the vehicle body, the vehicle body 2 is protruded based on a jack operation of an operator to lift and support the vehicle body 2. Are arranged.

An upper operating device 10a is mounted on the work table 8, and a lower operating device 10b is mounted on a rear portion of the vehicle body 2. These operating devices 10 (10a, 10b)
Is provided with an operation lever for operating the turntable 4 and the boom 5, and a worker boarding the worktable 8 operates the upper operation device 10 a to turn the turntable 4, raise and lower the boom 5, Actuation operations such as extension / contraction operations and swing operation of the worktable 8 can be performed, and a worker on the ground can operate the lower operation device 10b to perform similar operation operations.

The control device 3 is located adjacent to the lower operating device 10b.
0 is provided. The control device 30 includes the upper operating device 1
0a and an operation signal from the lower operation device 10b, and when the operation signal is input, the control device 30 responds to the operation signal to turn the turntable 4 by the turning motor 11 and to operate the boom 5 by the up / down cylinder 12. Of the boom 5 by the telescopic cylinder 13 and the swing mechanism 7
Of the worktable 8 is controlled. Specifically, each operation is performed by a hydraulic actuator such as a hydraulic motor or a hydraulic cylinder, and the control device 30 controls the operation of an electromagnetic control valve to control the hydraulic pressure supplied to each hydraulic actuator, and controls each hydraulic actuator. Controls the operation of.

For this reason, when the operator boarding the work table 8 operates the upper operating device 10a, or when the operator on the ground operates the lower operating device 10b,
The swivel table 4 is swung, the boom 5 is raised and lowered, the telescopic operation is performed, the work table 8 is swung, and the work table 8 is moved to a desired height.

A leveling mechanism 6 and a swing mechanism 7 are provided between the tip of the tip boom 5c and the worktable 8. FIG. 1 shows a front view of a tip end portion of a tip boom including a work table 8, and FIG. 2 shows a top view taken along the line II-II in FIG. 6 and the swing mechanism 7 will be described.

The leveling mechanism 6 comprises a leveling cylinder 60 and a link member 65. The leveling cylinder 60 is a so-called intermediate trunnion type hydraulic cylinder, and includes a cylinder body 61 and a piston rod (also referred to as a cylinder rod) 62 provided on the cylinder body so as to be able to expand and contract in the cylinder axis direction.

The leveling cylinder 60 is pivotally connected to the distal end of the distal end boom 5c at the distal end 62a of the piston rod 62 by a pivot pin 51, and is mounted to be swingable in the plane of the up-and-down angle (in the vertical plane) of the boom 5. Have been. Also,
One end 6 of a link member 65 is provided at the tip of the tip boom 5c.
5b is pivotally connected to the boom 5 by the pivot pin 52 so as to be swingable in the up-and-down angle plane, and the other end 65a of the link member is swung by the pivot portion 61a of the cylinder body 61 into the up-and-down angle plane of the boom 5. It is freely connected. That is, the leveling cylinder 60 is connected to the pivot portion 6 of the cylinder body.
1a, the pivot pin 52 of the link member and the pivot pin 51 of the tip end of the piston rod are swingably mounted in the surface of the boom 5 with three pivot axes.

A hydraulic pipe (not shown) is connected to the rod-side oil chamber and the bottom-side oil chamber of the cylinder body 61.
By supplying oil pressure to the bottom oil chamber, the piston rod 62 is extended from the cylinder body 61 to operate (the leveling cylinder 60 is extended), and by supplying oil pressure to the rod oil chamber, the piston rod 62 is retracted. (Same operation).

Here, of the three sides of the triangle formed by the three pivot axes described above, the side connecting the pivot shaft 61a of the link member 65 and the pivot pin 52, and the two pivots at the end of the boom. The length of the two sides connecting the connecting pins 51 and 52 is constant and does not change. On the other hand, when the leveling cylinder 60 is extended and contracted as described above, the length of the side connecting the pivot shaft 61a and the pivot pin 51 changes.
As a result, the triangle formed by the three sides is deformed, whereby the angle formed between the tip boom 5c having the side connecting the two pivot pins 51 and 52 and the leveling cylinder 60 having the expanding and contracting sides changes. I do.

FIG. 3 shows the leveling cylinder 6
FIG. 7 schematically shows how the leveling cylinder 60 is displaced with respect to the tip boom 5c to swing the work table 8 when the 0 is extended and retracted. Here, FIG.
Indicates the leveling cylinder 60 with respect to the tip boom 5c when the leveling cylinder 60 is fully extended.
The two-dot chain line indicates the leveling cylinder 60.
Shows the position state when is fully contracted.

As shown, three pivots 51, 5
The triangle formed by the three sides connecting the members 2 and 61a is greatly deformed by expanding and contracting the leveling cylinder 60. With this deformation, the leveling cylinder 60
Swings around the pivot pin 51 at the tip of the piston rod in the plane of the up-and-down angle of the boom 5 about the swing center, and the cylinder body 62
The work table 8 attached to the oscillating displacement is swung and displaced along a spiral movement path while changing the axial distance from the pivot pin 51 in accordance with the amount of protrusion of the piston rod.

Therefore, by controlling the expansion and contraction operation of the leveling cylinder 60, the angle formed between the tip boom 5c and the leveling cylinder 60 can be controlled, whereby the work table 8 can be moved to a desired position with respect to the tip boom 5c. It can be swung to an angular position.

In order to control the expansion / contraction operation of the leveling cylinder 60, a leveling valve 81 that swings integrally with the leveling cylinder 60 is attached to the tip portion 62a of the piston rod. Leveling valve 8
For example, for example, Japanese Utility Model Publication No.
No. 52, Japanese Utility Model Publication No. 6-44957, and the like can be used. This valve has a box body and a ball provided inside the box body, and the box body is tilted so that the ball inside can be moved right and left (in the boom tip direction or the base end direction in the undulating surface of the boom). ), The left or right pilot oil passage connected to the box is closed, and the valve spool is moved using the pressure difference between the left and right pilot oil passages generated at this time, so that the bottom side oil of the leveling cylinder is moved. Supply hydraulic oil to the chamber or rod side oil chamber.

For example, in the state shown in FIG. 1, if the upper end of the leveling cylinder 60 is inclined counterclockwise to the left (the left end of the worktable 8 is inclined to the lower left), the leveling cylinder 60 is attached to the tip of the piston rod. Leveling valve 8
1 tilts with this. Then, the ball moves leftward in the box body of the leveling valve 81 to block the left pilot oil passage connected to the box body, and the pressure difference between the left and right pilot pressures generated at this time moves the valve spool, and the hydraulic pressure is increased. Hydraulic oil is supplied to a bottom-side oil chamber of a leveling cylinder that communicates with the supply port. For this reason, the leveling cylinder 60 is extended and the leveling cylinder 60 is extended by the action of the above-described leveling mechanism (see FIG. 3).
Is pivoted clockwise. When the upper end of the leveling cylinder 60 is tilted rightward, it operates in the reverse of the above, causing the leveling cylinder 60 to perform a lengthening operation and swing counterclockwise.

Therefore, by mounting the leveling cylinder 60 so that the expansion and contraction axis of the leveling cylinder 60 and the perpendicular direction of the leveling valve coincide with each other, it is possible to perform the leveling operation so that the leveling cylinder 60 always maintains the vertical state. At this time, the expansion / contraction axis of the leveling cylinder 60 is always maintained vertical regardless of the up-and-down angle of the boom 5.

A swing mechanism 7 is provided above the cylinder body 61 coaxially with the cylinder axis. The oscillating mechanism 7 includes a housing 71 that covers an upper outer periphery of the cylinder body 61 and a worm wheel 7 that is fixed to a bottom end (upper end) of the cylinder body by a fastening means such as a bolt.
5. The housing 7 fixed to the outer peripheral surface of the housing 71
Work table brackets 72, 7 protruding from 1 in the work table direction
3. A worm gear 76 rotatably supported by the worktable bracket 72, meshing with the worm wheel 75, and rotationally driven by a swing motor (not shown).

A bearing is provided between the inner peripheral portion of the housing 71 and the outer peripheral portion of the cylinder body 61.
The housing 71 is supported on the cylinder body 61 by these bearings so as to be rotatable around the expansion / contraction axis of the cylinder. The worktable 8 is connected to workbench brackets 72, 73 fixed to the outer peripheral surface of the housing 71 and protruding in the workbench direction by connection pins 74, 74.

The worm gear 76 includes an upper operating device 10a.
Alternatively, by operating the lower operation device 10b to rotate the swing motor forward or backward, the oscillating motor rotates forward or backward, and thereby the worm wheel 75 meshing with the gear 76 is relatively rotated. As described above, the worm wheel 75 is fixedly disposed on the cylinder body 61, and the worm gear 76 is pivotally supported on the housing side rotatable with respect to the cylinder body 61. Therefore, by rotating the worm gear 76 forward or backward as described above, the worktable 8 can be horizontally turned clockwise or counterclockwise around the worm wheel 75.

Therefore, according to the leveling mechanism 6 configured as described above, since the leveling cylinder 60 is provided outside the end boom 5c, the leveling cylinder 60 according to the length and thickness of the leveling cylinder is provided inside the boom. There is no need to provide an installation part, whereby the entire boom 5 can be made thin, lightweight and compact, and the maintainability can be greatly improved. Further, since the leveling cylinder 60 itself has the function of the conventional vertical post, the boom tip and the leveling mechanism can be configured to be extremely simple and lightweight.

Further, the leveling mechanism 6 of the present invention has a swinging end which protrudes from the boom tip like a conventional vertical post, and whose protruding end position and protruding amount change according to the boom undulation angle. Therefore, there is no need to provide a swing arm as in the related art. Therefore, the worktable 8 can be directly connected to the cylinder body 61 of the leveling cylinder, or the worktable 8 can be directly connected to the housing 71 that swings, thereby simplifying the configuration around the worktable. While reducing the weight, the floor area of the worktable 8 can be increased by the area of the region A indicated by hatching in FIG.

Further, according to the leveling mechanism 6 of the present invention, when the boom 5 is lowered below the horizontal and the worktable 8 is moved down to the vicinity of the ground, the lowermost end is the lower end face of the worktable. Or it is the tip of the tip boom 5c. For this reason, even if the boom operation is incorrect near the ground, for example, these parts are in contact with the ground obstacles, etc., and are damaged by hitting functional parts such as the piston rod and its swinging end. There is no danger. Therefore, the leveling mechanism has high functional safety against erroneous operation.

In the above-described embodiment, an example in which the gravitational leveling valve 81 is disposed at the tip of the piston rod is disclosed.
For example, when the side of the cylinder body 61 or the bottom end portion or the worktable 8 does not swing, the worktable 8 is provided. May be. According to such a configuration, the floor area of the worktable 8 can be further increased.

In place of the gravity type leveling valve 81, an angle detector for detecting the inclination angle (absolute angle or relative angle formed with the boom 5) of the worktable 8 and the leveling cylinder 60 is provided around the worktable 8 and the leveling cylinder. It is also possible to provide an appropriate position such as a section and control the supply direction and supply amount of the hydraulic oil supplied to the leveling cylinder 60 based on the detected angle value so as to perform the leveling operation.

Next, FIG. 4 shows another embodiment of the present invention. This embodiment is different from the above-described embodiment in the configuration of the swing mechanism 7 and the worktable 8. The configuration of the leveling mechanism 6 attached to the distal end of the distal boom 5c is the same as that of the above-described embodiment, and the same reference numerals are given to the same main components, and description thereof will be omitted.

The oscillating mechanism 7 'comprises a turning base 71' fixed to the upper end of the leveling cylinder, and the turning base 7 '
A swivel 72 ′ supported on the 1 ′ via a bearing so as to be horizontally swivelable, and a swivel provided between the swivel base 71 ′ and the swivel 72 ′ to swing the swivel relative to the swivel base. It is configured with a motor (not shown) and the like,
The revolving shaft of the revolving base 72 'is provided on the telescopic shaft of the leveling cylinder. A worktable 8 '(also referred to as a work floor) having a large work area is fixed to an upper portion of the swivel base 72', and an upper operation for performing a boom operation and a swing operation of the worktable is mounted on the worktable 8 '. A device 10a 'is mounted.

Therefore, the worker on the work table 8 'can operate the upper operating device 10a' to move the boom 5 up and down, extend and retract, etc., and the leveling mechanism 6 is different from that of the above-described embodiment. By the same action, the telescopic axis of the leveling cylinder 60 is maintained vertically to operate the boom 5
The floor surface of the worktable 8 'is always kept horizontal regardless of the undulation angle. Further, the operator operates the upper operation device 10a 'to rotate the swing motor forward and reverse to rotate the swivel base 72' with respect to the swivel base 71 ', and the work table 8'
Can be swung.

[0042]

As described above, according to the present invention, the link member and the piston rod of the leveling cylinder are pivotally connected to the end of the boom in a vertical plane, respectively, so that the other end of the link member is connected to the leveling cylinder. A leveling mechanism is constituted by pivotally connecting the cylinder and a cylinder body in a vertical plane so as to swing freely. Then, a work table is attached to the cylinder body, and the leveling cylinder is extended and retracted, whereby the work table is swingably disposed in a vertical plane with respect to the boom, thereby constituting a high work apparatus.

Therefore, the configuration of the boom tip can be simplified, the high-altitude working device can be configured to be lightweight and compact, and the high-altitude operating device with improved workability and maintainability can be provided.

[Brief description of the drawings]

FIG. 1 is a front view of an end portion of a boom showing an embodiment of an aerial work apparatus according to the present invention.

FIG. 2 is a top view of a boom tip portion taken along the line II-II in FIG.

FIG. 3 is an explanatory diagram illustrating an operation of a leveling mechanism in the high-place working device.

FIG. 4 is a front view of a boom tip showing another embodiment of the high-altitude working device according to the present invention.

FIG. 5 is a front view showing a configuration of an aerial work vehicle which is an embodiment of the aerial work apparatus according to the present invention.

FIG. 6 is a front view showing a configuration of a boom tip portion in a conventional high-altitude working device.

[Explanation of symbols]

Reference Signs List 1 aerial work vehicle (aerial work equipment) 4 revolving base (base) 5 boom (5a base end boom, 5b intermediate boom, 5
c Tip boom) 6 Leveling mechanism 7 Swinging mechanism 8 Work table 60 Leveling cylinder 61 Cylinder body 62 Piston rod 65 Link member

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Masakazu Yawa, 1152 Yamashita, Ryoke, Ryouji, Ageo-shi, Saitama F-term (reference) 3F333 AA08 AB04 AC08 BB09 BD02 BE02

Claims (2)

[Claims] 1. A base, a boom attached to the base and movable up and down at least in a vertical plane, a leveling mechanism disposed at a tip end of the boom, and the boom via the leveling mechanism. A working table attached to the tip of the boom, wherein the leveling mechanism comprises: a link member having one end pivotally connected to a tip of the boom in a vertical plane, and a piston. A rod body pivotally connected to a distal end of the boom in a vertical plane and a cylinder body pivotally connected to the other end of the link member in a vertical plane; A high work device, wherein a table is attached to the cylinder body and is swingably disposed in a vertical plane with respect to the boom by extending and retracting the leveling cylinder. 2. The cylinder body is provided with a swing mechanism that is disposed coaxially with a telescopic axis of the leveling cylinder and that is rotatable about the telescopic axis with respect to the cylinder body. The high work apparatus according to claim 1, wherein the work apparatus is mounted on the cylinder body via the swing mechanism.