JPH0967090A - Vehicle for high lift work - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make a vehicle for high lift work having the high maximum height and the light weight in consideration of use in a building having a high ceiling. SOLUTION: A vehicle for high lift work is provided with a truck 1, a lift mast 2 provided on the truck 1 and able to be turned in the vertical surface and freely extended and contracted, and a workbench 3 connected to the lift mast 2. The lift mast 2 has the light weight and the relative long length in extending. Moreover, the lift mast 2 can be turned into the laying state, and the minimum height can be lowered. Accordingly, the vehicle for high lift work can easily pass a place in which the upper space is limited, for example, an entrance of a building. The lift mast 2 can raise the workbench 3 by being extended only when it is fixed by a lock pin 5 in the erected state. Accordingly, the lift mast 2 is not extended in the diagonal state, and the vehicle weight is needed to be increased for stably supporting the diagonally extending lift mast 2.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an aerial work vehicle which allows an operator and a load to be lifted and lowered, and allows an operator to work at a high place and can be used indoors.

[0002]

2. Description of the Related Art Conventionally, aerial work vehicles include a boom lifting type having a boom that can be expanded and contracted and its angle can be changed, as in a self-propelled crane, and a vertical lifting type that can lift a work table only in a vertical direction. Are known. The boom lifting type aerial work vehicle is capable of raising and lowering the work platform to a relatively high position like a crane, and there are some which can raise and lower the work platform to 30 m or more. On the other hand, the above-mentioned vertical elevating type work at a high place is used at a relatively low position, and in general, the workbench can only be moved up and down by about 5 m.

[0003]

However, in sports facilities such as a gymnasium and buildings such as halls, the height of the interior is high, and it is necessary to construct a scaffold for construction work such as interior decoration. was there. Therefore, it is conceivable to reduce the cost and the construction period by using the above-described work platform for aerial work and omitting the temporary process of assembling the scaffolds when constructing the interior of the room.

However, the boom lifting type aerial work vehicle is considerably heavy so that the work platform can be stably supported even when the boom is tilted, and the boom is reduced. It was relatively long, and it was difficult to handle it in a narrow space even when the boom was laid down. Therefore, in terms of weight, minimum vehicle height, and vehicle length, it is difficult for the boom lift type aerial work vehicle to be carried into a limited space such as indoors, and the use place is limited. It was

On the other hand, the vertical lift type work platform does not support the work table with the boom inclined, unlike the boom lift type work vehicle. , Many are relatively lightweight. In addition, since the vertical lift type work platform is basically capable of raising the work platform only to a lower position, the vehicle itself is compact, and it is relatively easy to use indoors in terms of vehicle weight and vehicle size. Some of them could be carried into a limited space, such as the one described above, and were versatile.

However, as described above, in the lightweight and compact vertical lift type aerial work vehicle, the work table has a maximum ground clearance of about 5 m, and for buildings such as sports facilities having a high indoor height, It was not always possible. Further, among the above-described vertical lifting type aerial work vehicles, there is a work table having a maximum ground clearance of about 10 m. However, when the work table can be raised to such a relatively high position, The weight was considerably heavy, and the vehicle height was high even when the workbench was at the lowest position, making it difficult to carry it indoors.

The present invention has been made in view of the above circumstances, and it is an object of the present invention to provide an aerial work vehicle which is light in weight and is capable of raising and lowering a work table to a relatively high position. Is.

[0008]

The aerial work vehicle of the present invention comprises:
Self-propelled bogie, multi-stage boom provided on the bogie, rotatable in a vertical plane and expandable / contractible, fixing means capable of fixing the boom in an upright state, and connected to the tip of the boom And a work table that can be raised and lowered in response to expansion and contraction of the boom, and the boom can be extended only when the boom is fixed in an upright state by the fixing means. It was used as a solution to the problem.

According to the above construction, even in an aerial work vehicle having a multi-stage boom that can rotate in a vertical plane, the work platform must be raised and lowered only when the boom is fixed in an upright state. Compared with aerial work vehicles that extend the boom diagonally, even when the vehicle is lightweight, it can support the workbench stably and can work up and down the workbench to a relatively high position. The weight of the car can be reduced. In addition, if the boom is laid down without the boom being extended, the minimum vehicle height can be lowered.

The trolley may be of a tire type, a crawler type, a track type, or the like, but it is lightweight and has high stability, and in consideration of indoor use, a rubber crawler is used. The formula is preferred. The power of the trolley is
Although a gasoline engine, a diesel engine, an electric motor, or the like can be used, it is preferable to use an electric motor using a battery in consideration of indoor use.

The boom may have the same construction as the boom of the crane.
In order to reduce the weight, it is preferable to use a lightweight material, for example, an aluminum-rich material. Regarding the extension and contraction of the boom, the same means as the drive means for driving the boom of the crane to extend and retract can be used, and a wire and winch, a hydraulic cylinder, a hydraulic cylinder and a sprocket, a chain and the like can be used.

Regarding the rotational movement of the boom in the vertical plane, the same driving means as the crane boom angle can be used, and a wire, winch, hydraulic cylinder, etc. can be used. . As the fixing means, any means may be used as long as it can firmly fix the mast in a vertical state, and for example, a fixing means using a lock pin may be used.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, an example of an embodiment of an aerial work vehicle of the present invention will be described with reference to the drawings. 1 to 3 show the appearance of an aerial work vehicle according to an example of the above-described embodiment, and FIGS. 4 to 6 show the inside of the aerial work vehicle by imaginary lines or by cutting a part thereof. FIG. 7 shows an aerial work vehicle during aerial work, and FIGS. 8 and 9 show an undulating operation of the aerial work vehicle, which will be described later.

As shown in FIGS. 1 to 6, the aerial work vehicle is rotatably connected to a self-propelled trolley 1 from a state lying on the trolley 1 to an upright state, and An extendable and retractable lift mast (boom) 2, a workbench 3 that is connected to the tip of the lift mast 2 and that can be moved up and down according to the extension and contraction of the lift mast 2, and the lift mast 2 is extended and contracted to perform the above-mentioned work. A hydraulic cylinder (not shown) for extending and lowering the table and a lift cylinder (shown in FIG. 4) for rotating the lift mast 2 between a lying state and an upright state.
4, a lock pin (shown in FIG. 1) capable of fixing the lift mast 2 in an upright state, and a limit switch (shown in FIG. 4) 6 for detecting a fixed or non-fixed state of the lock pin 5. A control panel 7 incorporating a control device for controlling the hydraulic cylinder for expansion and contraction and the lift cylinder 4
And a limit switch (shown in FIG. 4) 8 for detecting whether or not the lift mast 2 is lying at a predetermined angle.

The trolley 1 is of a crawler type which is driven by crawlers 1a and 1a, as shown in FIG.
As the crawler shoes, lightweight white rubber crawler shoes 1b, 1b are used, and the weight of the trolley 1 is reduced, and the rubber crawlers 1a, 1a stabilize the relatively wide installation surface. .

As shown in FIG. 4, the trolley 1 is provided with a DC motor 1c and a speed reducer 1d, and is driven by electric power supplied from a battery 1e. Because there are few, it is possible to run indoors. Further, as shown in FIG. 1, the carriage 1 is provided with a mast fixing portion 1f that supports the lift mast 2 so that the lift mast 2 can be undulated from a lying state to an upright state.

The mast fixing portion 1f rotatably supports the lift mast 2 by means of a mast fixing pin 1g. Further, as shown in FIG. 9, the mast fixing portion 1f is provided with a through hole 1h through which the lock pin 5 penetrates. By allowing the lock pin 5 to penetrate the mast fixing portion 1f and the lift mast 2, The lift mast 2 can be fixed in an upright state. Also, the through hole 1
When the lock pin 5 is inserted into h, it can be detected that the lock pin 5 comes into contact with the limit switch 6 and the lift mast 2 is fixed in an upright state.

Further, the carriage 1 includes a lower operating device (shown in FIG. 3) 1i for operating a work vehicle at high altitude, and a work table 3
A step 1j for getting in and out of the vehicle and a hoisting / lifting manual switching valve 1k are provided. The lift mast 2 is the first
It is a six-stage type from the mast 2a to the sixth mast 2f, and each of the first to sixth masts 2a to 2f has a square tubular shape, and the second mast 2b is inserted into the first mast 2a. The third mast 2c is inserted into the second mast 2b, and the upper mast is sequentially inserted into the lower mast.

A second mast 2b is connected to the first mast 2a via the expansion / contraction hydraulic cylinder (not shown), and the expansion / contraction hydraulic cylinder makes a second connection with respect to the first mast 2a. The mast 2b is adapted to extend and retract. The mast that has moved to the third mast 2c is connected to the lower mast by a chain and a sprocket, and extends and retracts in response to the extension and retraction of the lower mast.

Therefore, the lift mast 2 extends the second mast 2b with respect to the first mast 2a by extending the piston rod (not shown) of the expanding and contracting hydraulic cylinder, and the masts after the third mast 2c are expanded. Stretch by chain and sprocket, and as shown in Figure 7,
The entire lift mast 2 can be extended. Also, by adjusting the extension length of the hydraulic cylinder for expansion and contraction, the extension length of the entire lift mast 2 can be adjusted.

Further, the lift mast 2 has a structural steel plate welding structure and an aluminum alloy welding structure, and its main part is made of aluminum alloy to reduce the weight.
Further, the base portion of the first mast 2a is rotatably connected to the mast fixing portion 1f on the carriage 1 as described above, and has a through hole 2g for allowing the lock pin 5 to pass therethrough as shown in FIG. Have. Further, the base of the first mast 2a is connected to the lift cylinder 4, and when the lift cylinder 4 is contracted, the lift mast 2 is upright as shown in FIG. 8 and the lift cylinder 4 is expanded. In this state, the lift mast 2 rotates about the mast fixing pin 1g as an axis, and as shown in FIG. 9, the lift mast 2 lays down at a predetermined angle set in advance.

Further, as shown in FIG. 9, when the lift mast 2 lies at a predetermined angle, the base of the lift mast 2 comes into contact with the limit switch 8 shown in FIG. When the base portion of the shift mast 2 comes into contact with the shift mast 2, it is possible to detect that the lift mast 2 is in a sleeping state at a predetermined angle. Further, a workbench connecting portion 2h for connecting the workbench 3 is provided at the upper end of the sixth mast 2f.

The work table 3 includes a work floor 3a and a work floor 3
It has a handrail 3b provided so as to surround a, and an upper operation device 3c for operating the aerial work vehicle from the workbench 3 side is provided. Also, the upper operation device 3c
The lift mast 2 raises and lowers the workbench 3, and the trolley 1
Is equipped with an emergency stop switch 3d, and when the operation of the aerial work vehicle cannot be controlled by operating the upper operation device 3c, the operation of the aerial work vehicle is emergency stopped. You can do it. That is, in an aerial work vehicle, the work table 3 can be lifted up and down from the work table 3 and the carriage 1 can be operated.

Further, a foot switch 3e is provided below the upper operating device 3c, and the upper operating device 3c can be operated only when the foot switch 3e is stepped on to prevent erroneous operation. ing. Further, in the control device built in the control panel 7, the operation of the hydraulic cylinder (not shown) for expansion and contraction is performed based on the output signal from the limit switch 6 while the lift mast 2 is fixed by the lock pin 5. The operation of the lift cylinder 4 is prohibited, and the operation of the hydraulic cylinder for expansion and contraction (not shown) is prohibited while the lift mast 2 is not fixed by the lock pin 5 and the operation of the lift cylinder 4 is allowed. It is supposed to do.

Further, in the control device built in the control panel 7, based on the output signal from the limit switch 6, while the lift mast 2 is fixed by the lock pin 5, the traveling of the truck is permitted, and While the lift mast 2 is not fixed by the lock pin 5, traveling of the dolly is prohibited, and the lift mast 2 is not fixed by the lock pin 5 based on the output signals from the limit switch 6 and the limit switch 8. When the lift mast 2 lays at a predetermined angle, the carriage is allowed to travel. That is, traveling of the carriage is prohibited only while the lift mast 2 is rotationally moved by the lift cylinder 4.

Further, the aerial work vehicle, as shown in FIG.
As a device for preventing overloading, a trolley 1 is provided with a pressure switch 9 for detecting overloading and a limit switch 10 for detecting a rise above a predetermined height of the workbench 3, and based on an output signal from this, , The control device is the work floor 3a
When the load weight on the workbench 3 becomes a predetermined weight or more when the height of the workbench is equal to or higher than a predetermined height, the operation of the expansion / contraction pressure cylinder of the lift mast 2 is stopped, and the workbench 3 moves to the predetermined height. You can't rise any more.

Further, in the aerial work vehicle, a stop valve (shown in FIG. 6) that lowers the work floor by opening this valve when the work floor does not descend due to a failure of the electric system etc. ) 11 and an alarm buzzer 12 for calling attention to the surroundings while the vehicle is traveling and the work platform is being raised and lowered. In addition, the aerial work vehicle includes a trolley 1 and an inclination sensor 13
When the vehicle body tilts forward and backward and leftward and rightward by a predetermined angle or more, the control device smoothes the alarm buzzer 12 based on the output signal from the tilt sensor 13,
It is supposed to prohibit the rise of.

Further, the control device is such that the tilt sensor 13 is
And the output signal of the limit switch 10 for detecting the rise of the workbench 3 above a predetermined height, when the workbench is less than the predetermined height, the vehicle body must be tilted by a predetermined angle or more, The preset high-speed traveling is enabled, and when the vehicle body is inclined by a predetermined angle or more, the high-speed traveling is prohibited and only the preset low-speed traveling is possible. Further, when the workbench is at a predetermined height or more, if the vehicle body is not tilted by a predetermined angle or more, only the low speed traveling is possible, and when the vehicle body is tilted by a predetermined angle or more, the traveling of the carriage 1 is prohibited. There is.

In addition, the lift cylinder 4 is installed in an aerial work vehicle.
A fuse valve 14 that is attached to the bottom side pipe to block the outflow of oil when the pipe hose is broken and prevents the workbench from falling, and a relief valve (shown in FIG. 6) 15 that prevents abnormal pressure in the hydraulic circuit. Is provided.

Next, the operation of the aerial work vehicle having the above structure will be described. First, in the above work platform for aerial work, the work platform 3 is lifted and lowered by the lift mast 2 having substantially the same structure as the crane and the boom. It is supposed to be performed only in the upright state.

Therefore, it is not necessary to provide a counterweight on the truck 1 as in the case where the boom is extended obliquely, and it is possible to reduce the weight of the aerial work vehicle. In addition, a vertical lifting type work platform using a multi-stage boom has been conventionally known, but in the conventional case, the thickest part of the boom is raised and lowered to the uppermost, contrary to the crane boom. It was supposed to do. That is, the workbench was fixed to the thickest part of the multistage boom, and the thin part of the boom was fixed to the trolley side.

Therefore, in the conventional vertically elevated work vehicle using the boom, it is easy to fix the workbench to the boom, but the upper part of the boom becomes heavier.
The center of gravity of the boom became high, and it was necessary to make the bogie heavy in order to stably support the boom. On the other hand, in the aerial work vehicle of the embodiment, the lift mast 2
Since the thickest first mast 2a is arranged on the lowermost side and the thinnest sixth mast 2f is used on the uppermost side of the lift mast 2, the center of gravity of the lift mast 2 is lowered to reduce the weight of the trolley 1. Can be realized.

Further, the weight of the lift mast 2 can be reduced by using a large amount of lightweight aluminum alloy for the lift mast 2, and the weight of the lift mast 2 enhances the stability of the trolley 1. The weight can be reduced. Further, since the trolley 1 is a crawler type using a white rubber crawler shoe, it is lightweight as a crawler type, and a wide ground contact area can be secured as a crawler type, thus stabilizing and reducing the weight of the trolley 1. Can be planned.

Therefore, since the lift mast 2 has a low center of gravity and is lightweight, even if the lifting distance of the workbench 1 by the lift mast 2 is increased and the maximum ground clearance of the workbench is increased to some extent, the aerial work vehicle is in a lightweight state. In addition, since the carriage 1 is lightweight, it is possible to use an aerial work vehicle having a high maximum ground clearance of about 10 m indoors.

Further, in order to move the aerial work vehicle indoors, it is necessary to pass through an entrance / exit with a low height limit of the building.
With this, since it is rotatably connected from a state in which it is laid down at a predetermined angle to a state in which it is erected, and it can be rotated and moved by the lift cylinder 4, the minimum ground clearance can be lowered by keeping the lift mast 2 in a laid state. . Therefore, by moving the carriage 1 while the lift mast 2 is laid down, the aerial work vehicle can pass through the entrance / exit of the building, and the aerial work vehicle can be used indoors. You can

Further, the lift mast 2 can be fixed in an upright state on the carriage 1 by a lock pin 5, but if the lock pin 5 does not detect the fixation by the limit switch 6, the control device lifts the lift mast. Mast 2
The extension of the lift mast 2 is prohibited and the lift cylinder 4 is allowed to be lifted and lowered.
Further, when the fixing by the lock pin 5 is detected by the limit switch 6, the control device is operated by the lift mast 2.
Of the lift cylinder 4 and the lifting operation of the lift mast 2 by the lift cylinder 4 is prohibited.

Further, the control device is a limit switch 6
When the lock pin 5 does not detect that the lift mast 2 is fixed, and the limit switch 8 does not detect that the lift mast 2 is lying at a predetermined angle, that is, when the lift mast 2 is When the vehicle is rotating and moving between a sleeping state and an upright state, traveling by the carriage 1 is prohibited. Due to the operation of the above control device, erroneous operation is prevented, and it becomes possible to easily operate the aerial work vehicle.

Further, the aerial work vehicle can be moved indoors to perform aerial work, as described above, by reducing the weight and inclining the lift mast 2 when moving, and at a sports facility or the like. As described above, it is possible to reduce the cost and the construction period by eliminating the need to temporarily install scaffolds in the construction such as interior decoration in a place where the indoor height is high.

The lift mast 2 is not limited to the six-stage type, but the number of stages is increased to lower the minimum ground clearance of the lift mast 2 or the number of stages is decreased to increase the lift mast 2. The structure may be simplified. However, if you increase the number of steps too much, the number of moving parts increases and high precision is required to prevent backlash.
High cost. Further, if the number of steps is reduced too much, the minimum ground clearance of the aerial work vehicle will increase even if the lift mast 2 can be tilted.

[0040]

According to the aerial work vehicle of the present invention, in an aerial work vehicle using a boom that is rotatable in a vertical plane and is extendable and retractable, the boom can be mounted only when the boom is fixed in an upright state. Since the workbench can be raised by extension, it is not necessary to increase the weight of the trolley to support the boom that has been extended obliquely, and the aerial work vehicle that can raise the workbench relatively high is lightweight. Since it can be used indoors, it is possible to reduce costs and shorten the construction period by eliminating the need to temporarily install scaffolds when constructing interiors in places with high indoor height such as sports facilities. Can be planned.

Further, the aerial work vehicle of the present invention has a relatively high maximum vehicle height since it can be rotatably moved and laid down while the boom is contracted, unlike the conventional vertical lifting type vehicle. Also, the minimum vehicle height can be lowered, and the vehicle can easily pass through a place with a low height limit such as an entrance / exit of a building.

[Brief description of drawings]

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

FIG. 2 is a front view showing an aerial work vehicle of the above example.

FIG. 3 is a plan view showing an aerial work vehicle of the above example.

FIG. 4 is a side view with a part removed for explaining the inside of the aerial work vehicle of the above example.

FIG. 5 is a front view with a part removed for explaining the inside of the aerial work vehicle of the above example.

FIG. 6 is a plan view for explaining the inside of the aerial work vehicle of the above example.

FIG. 7 is a side view showing a state in which the lift mast of the aerial work vehicle of the above example is extended.

FIG. 8 is a partially cutaway side view for explaining a method of inclining a lift mast of the aerial work vehicle of the above example.

FIG. 9 is a partially cutaway side view for explaining a method of inclining a lift mast of the aerial work vehicle of the above example.

[Explanation of symbols]

 1 dolly 2 lift mast (boom) 3 workbench 5 lock pin (fixing means)

Claims (1)

[Claims] 1. A self-propelled trolley, a multi-stage boom mounted on the trolley and rotatable in a vertical plane and capable of expanding and contracting, a fixing means capable of fixing the boom in an upright state, and the boom. And a worktable connected to the tip of the boom and capable of moving up and down in response to expansion and contraction of the boom. The boom is extendable only when the boom is fixed in an upright state by the fixing means. The aerial work vehicle characterized by being.