JP3068419B2 - Safety equipment 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 an aerial work vehicle equipped with a working device such as a boom on a vehicle body and a jack for stably supporting the vehicle body. The present invention relates to a safety device for an aerial work vehicle that regulates a working range of a working device provided.

[0002]

2. Description of the Related Art Wiring of electric wires arranged between telephone poles, etc.
When performing high-altitude work outdoors, expand and contract on the body,
An aerial work vehicle configured by providing a boom that can freely perform operations such as raising and lowering, turning, and the like, and further providing a work table at the tip of the boom is often used. Then, by performing operations such as extension and raising of the boom, the worker who is on the work table can be moved to a desired high place to perform high-place work.

In such an aerial work vehicle, the vehicle body can be stably supported against a moment acting on the vehicle body in the direction of overturning when the boom is extended or raised / lowered (hereinafter referred to as "overturning moment"). Thus, jack devices are provided on the front, rear, left and right sides of the vehicle body. This jack device is configured by attaching a ground plate to the lower end of a jack that is provided so as to be able to extend downward. Then, the vehicle body is supported on the ground by lowering the ground plate (extending the jack) until a ground reaction force is obtained. On the other hand, when running the work vehicle, the grounding plate is pulled up and stored in the vehicle body.

In the aerial work vehicle constructed as described above, since the vehicle body is supported by wheels provided on the front, rear, left and right of the vehicle body, even if the jack is not grounded, the boom can be operated. In addition, there is an operating range of the boom (body stability maintaining range) in which the wheels can resist the overturning moment and the vehicle body does not become unstable. However, a high work vehicle is often provided with a jack interlock mechanism to ensure safety during work. This jack interlock mechanism allows the boom to be completely contracted when the jack is in a non-grounded state (a state in which it is not extended until a ground reaction force is obtained), and holds the folded down state to control each operation of the boom. Along with regulating,
If the boom is not in the stored state, the jack cannot be stored. As a result, the aerial work vehicle cannot start the aerial work until the vehicle is stopped and the jack is touched down, and the jack cannot be stored when the boom is upright and extended. Therefore, the vehicle cannot run.

[0005]

However, hangers are provided at equal intervals on messenger wires stretched between utility poles, and work positions at high places, such as a hanger-hanging work in which a communication wire is hung on this hanger. When working continuously while moving the vehicle, it was necessary to frequently move the aerial work vehicle. Here, in order to move the aerial work vehicle, the jack interlock mechanism requires the boom to be retracted to the retracted position, and then the jack must be retracted and the vehicle must travel to make the work complicated. Therefore, there is a problem that the working efficiency is reduced.

When the working position is at a relatively low position, or when the height of a work vehicle at a high place has a wide vehicle body stability maintaining range when the jack is not touched, the boom is raised and extended when the jack is not touched. And moving the work table to the work position, the vehicle body does not become unstable. However, even in such a case, there is a problem that the work efficiency is reduced because the jack needs to be grounded.

SUMMARY OF THE INVENTION The present invention has been made in view of such a problem, and a safety device for an aerial work vehicle capable of performing an efficient operation when performing a continuous operation while moving at an altitude. It is intended to provide.

[0008]

In order to achieve the above object, a safety device for an aerial work vehicle according to the present invention is capable of being stored on a vehicle body having wheels and capable of running down. At the same time, a boom is arranged so as to be able to freely move up and down from the position stored in this way, and a jack device that is in contact with the vehicle body and supports the vehicle body is provided so as to be groundable and retractable. Jack operating means for performing operation control, and a boom for detecting whether or not the position of the boom is within a vehicle body stability maintaining range in which a predetermined body stability can be maintained in a state where the jack device is housed and the wheels are in contact with the ground. The safe position detecting means and the housing operation of the jack device by the jack operating means only when the boom safe position detecting means detects that the position of the boom is within the vehicle body stability maintaining range. Constructed and a permissible jacking allowable operating means. As a result, when the position of the boom is within the vehicle body stability maintaining range, that is, when the position of the boom is within a range in which the vehicle body can be stably supported by the wheels without grounding the jack device, the vehicle body stability is impaired. Since there is no fear, even when the boom is not stored, the jack device can be stored and the vehicle body can be driven in a stable state.

Further, when the boom is in the vehicle body stability maintaining range excluding the storage position, the jack operation permitting means may be configured to perform a temporary storage operation of raising the jack device by a predetermined amount from the contact state of the jack device. Good. Here, when the jack device is lifted and the predetermined amount of lift is set to the minimum lift amount at which the vehicle body can travel, when the jack is stored and the vehicle body travels during work, from the grounding state of the jack device to running the vehicle body. Time can be shortened.

Further, only when the grounding operation of the jack is detected by the grounding detecting means for detecting the grounding operation of the jack device, the operation of the boom out of the vehicle body stable support range is permitted by the boom operation permitting means. May be. Thus, unless the jack device is grounded, the operation of the boom that makes the vehicle body unstable is regulated, so that the stability of the vehicle body can be ensured.

When the aerial work vehicle is an aerial work vehicle provided with a worktable on which a worker can ride at the end of a boom, the worktable is provided with jack operating means. Is also good. Accordingly, when the boom is in the stable support range of the vehicle body, the worker on the work table can perform the storage operation control of the jack device, so that quick work can be performed even when the vehicle body is driven. it can.

The boom safe position detecting means is configured to compare the boom operating position detected by the boom state detecting means with a predetermined operating range by the boom state comparing means. Since the boom operation position can be detected based on the undulation angle and the like, it is possible to detect whether or not the boom is within the vehicle body stability maintaining range with a simple configuration. Also, when the boom safety position detecting means is configured to compare the boom moment detected by the boom moment detecting means with a predetermined moment by the moment comparing means, the boom moment changes even when the boom operating position is constant. In some cases, it is possible to reliably detect whether the boom is within the vehicle body stability maintaining range.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below with reference to the drawings. First, an aerial work vehicle equipped with a safety device for an aerial work vehicle according to the present invention will be described with reference to FIG. In this aerial work vehicle 1, a swivelable swivel 5 is disposed at the rear of a car body 4 that can travel freely, and a boom 2 configured to be extendable and retractable is pivotally mounted on the upper part of the swivel 5 so as to be able to move up and down. doing. A worktable 3 on which a worker can ride is attached to the tip of the boom 2. Then, the operator gets on the work table 3 and controls the operation of the operation means 6, thereby operating the swivel table 5 and the boom 2 and moving to an arbitrary height to perform work.

A jack device 10 is provided on the front, rear, left and right sides of the vehicle body 4.
Is provided. The jack device 10 includes an outrigger beam 11 provided so as to be able to expand and contract toward the side of the vehicle body 4, and a jack 13 provided at the tip of the outrigger beam 11 so as to be able to extend downward. I have. The jack 13 includes an outer post 13 a attached to the outrigger beam 11 and an outer post 1.
An inner post 13b which can be extended and retracted with respect to 3a. A ground plate 12 is attached to the lower end of the inner post 13b. The ground plate 12 is grounded by extending the inner post 13b downward, and the vehicle body 4 is stably supported. The extension operation of the inner post 13b is performed until the ground reaction force acts on the jack device 10. And when the aerial work vehicle 1 travels,
The jack device 10 is housed by reducing the outrigger beam 11 in the direction of the vehicle body 4 and reducing the inner post 13b.

Next, a safety device for an aerial work vehicle that controls the operation of the boom 2, the jack device 10, and the like in the aerial work vehicle 1 configured as described above will be described with reference to FIG. The safety device for the aerial work vehicle is composed of a boom safety position detecting means 31, a ground contact detecting means 32, an operating means 6, and a controller 20. The boom safe position detecting means 31 determines whether or not the boom 2 is positioned within a range in which the vehicle body 4 can be stably supported against the overturning moment in a state where the jack device 10 is not in contact with the ground (the vehicle body stable maintenance range). State detection means for detecting the position (boom state) of the boom 2 and a predetermined operation range (vehicle body stability maintaining range) in which the boom operation position detected by the boom state detection means is determined in advance. And a boom state comparison means for comparing and detecting whether or not the vehicle is within the vehicle.

Here, as shown in FIG. 5, the vehicle body stability maintaining range is represented by B in a range in which the boom 2 can be raised and lowered and extended and retracted from the storage position (in a fully collapsed state or a fully contracted state). Range. The range indicated by A exceeding B is the position of the boom 2 (operable allowable range) where the vehicle body 4 can be stably supported against the overturning moment with the jack device 10 grounded. The boom state detection means is configured to detect the amount of expansion and contraction and the undulation angle of the boom 2 by using a detection sensor and calculate the detected value by calculating the detected value.
The position of the boom 2 may be determined by providing a gyro to the boom.

The contact detecting means 32 detects whether or not the inner post 13b extends downward until the jack device 10 receives a contact reaction force. This detection is performed by a limit switch or a load cell provided in the jack device 10. The operating means 6 includes a jack operating means 6 a for controlling the operation of the jack device 10 and a boom operating means 6 b for controlling the operation of the boom 2. This operation means 6
It is a remote control means constituted by a control valve for controlling supply and discharge of hydraulic oil to and from the jack device 10 and the boom 2 operated by hydraulic pressure, and an operation lever for operating the control valve. The operation device 6 is a wireless remote controller using an optical signal or the like, and the jack device 1 is operated by remotely operating a control valve disposed on the vehicle body 4.
It may be configured to perform operation control of 0 and the boom 2.

The controller 20 is provided with jack operation permitting means 21 and boom operation permitting means 22. The jack operation permitting means 21 is provided only when the boom safe position detecting means 31 detects that the boom 2 is located in the vehicle body stability maintaining range B.
0 is permitted. Here, the storage operation of the jack device 10 is performed by setting the outrigger beam 11 to the vehicle body 4.
The jacking means 6a includes a full storage operation for reducing the size of the inner post 13b into the outer post 13a and a temporary storage operation for raising and holding only the inner post 13b by an amount by which the vehicle body 4 can travel.
Is configured to be selectable.

Here, when the jack operation means 6a performs the storing operation of the jack device 10 in the state where the temporary storing operation is selected, the jack device 10 is temporarily stopped except when the boom 2 is in the storage position. Perform storage operation. When the boom 2 is in the storage position, the vehicle body 4 does not need to be stably supported by the jack device 10, so that the jack device 10 performs a complete storage operation. The detection of whether or not the boom 2 is at the storage position may be performed based on a detection signal from the boom state detection unit.
A configuration may be adopted in which a storage detection signal is transmitted at the storage position of the boom 2 and a limit switch (not shown) provided on the vehicle body 4 is used.

The boom operation permitting means 22 permits the operation of the boom 2 from the vehicle body stability maintaining range B to the operation allowable range A only when the grounding of the jack device 10 is detected by the ground detecting means 32. . Therefore, in a state where the jack device 10 is not grounded, the boom 2 can perform an operation such as an up and down movement within the vehicle body stability maintaining range B.

A case of using the aerial work vehicle 1 configured as described above to perform a hanger mounting work in a communication work will be described with reference to FIGS. 1 and 2. FIG. The work of hanging a hanger refers to a hanger 3 provided at intervals of about 1 m on a messenger wire 31 stretched between utility poles 30, 30.
This is the work of hanging the communication wire 33 on the second wire.

Here, when performing the work of hanging the hanger,
A case in which the amount of ups and downs and extension of the boom 2 necessary for moving the work table 3 to the work position where the worker M works is located within the vehicle body stability maintaining range B will be described with reference to FIG. In this case, the boom operation permitting means 22 can perform operations such as raising and lowering, expanding and contracting the boom 2 even when the jack device 10 is in a non-ground state. For this reason, when performing the hanger hanging work from left to right in FIG. 1, the hanger 32 is provided from the left working position shown by the two-dot chain line to the right working position shown by the solid line. The aerial work vehicle 1 can be driven and stopped according to the interval. Therefore, if two persons, the worker M on the workbench 3 and the driver (not shown) on the aerial work vehicle 1, perform the work, the hanger hanging work can be performed efficiently and quickly.

Next, the amount of ups and downs and extension of the boom 2 required for moving the work table 3 to the work position where the worker M works is located beyond the vehicle body stability maintaining range B and within the operation allowable range A. Will be described with reference to FIG.
In this case, it is necessary to perform the grounding operation of the jack device 10 in order to perform the work of hanging the hanger. Therefore, as a method of performing the work, a method of performing the work by running and stopping the aerial work vehicle 1 corresponding to the interval at which the hanger 32 is provided in the same manner as described above, and a method of hanging the hanger 32 of the adjacent hanger 32 Is performed by moving the work table 3 by raising and lowering the boom 2 and expanding and contracting the boom 2.
There is a method of traveling and stopping the high-altitude work vehicle 1 for the interval of (1) to perform the work.

When the aerial work vehicle 1 is run in each of the above-described working methods, the worker M on the work table 3 operates the boom operating means 6b from the work position indicated by the two-dot chain line to move the boom 2 The boom 2 is moved down and down until it is positioned in the vehicle body stability range B indicated by the dashed line. Then, the jack device 10 is stored by operating the jack operating means 6a. Here, the storing operation is selected so as to perform the temporary storing operation. This eliminates the need to store the boom 2 to the storage position, and allows the aerial work vehicle 1 to travel without completely storing the jack device 10, so that the aerial work vehicle 1 can be moved quickly. It can be carried out. After the aerial work vehicle 1 is moved to a desired position, the jack device 10 is grounded again as indicated by the solid line, and the work table 3 is again operated by performing operations such as raising the boom 2. Move to position.

According to the safety device for an aerial work vehicle configured as described above, the operation of the boom 2 and the jack device 10 can be controlled from the work table 3 and the work position can be moved. When it becomes necessary to perform the grounding operation of the jack device 10, the worker M may perform the lowering operation of the inner post 13b from the worktable 3. When it becomes necessary to run the aerial work vehicle 1, the inner post 13b may be raised by a predetermined amount.

Next, another example of the present invention will be described with reference to FIG. As in the case of the aerial work vehicle 10, the aerial work vehicle 40 is provided with a swivel 45 on a vehicle body 44, and the boom 42 is arranged on the swivel 45 so as to be able to move up and down. A vertical post 48 is provided at the distal end of the boom 42 to maintain the vertical position at all times. The vertical post 48 is provided with a worktable 43 via a swing arm 47 which can be horizontally turned.

In the aerial work vehicle 40 configured as described above, the worktable 4
3 is located in front (F direction),
Is located rearward (in the direction B).
Are different. That is, when the elevation angle and the extension amount of the boom 42 are the same, when the work table 43 is turning backward as shown by the solid line, the work table 43 turns forward as shown by the two-dot chain line. The moment M of the boom 42 is larger than when the user is in the position.

Therefore, in such an aerial work vehicle 40, it is determined whether or not the boom 42 is in the vehicle body stability maintaining range in which the predetermined vehicle body stability can be maintained, as described above. It is determined not only from the boom position detected based on the undulation angle and the amount of expansion and contraction but from the moment M of the boom 42. Therefore, the boom safe position detecting means 31 comprises a boom moment detecting means for detecting a moment of the boom 42 and a moment comparing means for comparing a moment detected by the boom moment detecting means with a predetermined moment. Have been.

The moment of the boom 42 is obtained by detecting a force acting on the up-and-down cylinder 41 for performing the up-and-down operation of the boom 42, and the weight, the up-and-down angle, the extension amount of the boom 42, the load of the work table 43, and the turning. It is calculated based on the turning angle of the arm 47 and the like. Then, the detected moment is compared with a predetermined moment (moment in the vehicle body stability maintaining range) by a moment comparing means. If the detected moment is within the predetermined moment, the controller 20 The same operation control as when the boom 2 is within the range indicated by B in FIG. 5 is performed, and when the detected moment exceeds a predetermined moment, the boom 2
And the same operation control as when it is within the range represented by A in FIG.

In the aerial work vehicle 40 configured as described above, the boom is operated in the same boom state due to the turning operation of the work table 43 provided at the tip of the boom 42 and the fluctuation of the load of the work table 43. Even if the moment changes, appropriate operation control of the jack device 10 and the boom 42 can be performed without impairing the stability of the vehicle body 44.

In each of the above-described embodiments, the work vehicle having a work table provided at the tip of a boom that can freely move up and down, extend and retract, turn, etc. has been described as an aerial work vehicle. The invention is not limited to this, and it may be any high-altitude work vehicle provided with a boom capable of at least raising and lowering operation, and may be used in a crane truck or the like. Further, the case where the jack device is a so-called outrigger jack device provided with an outrigger beam capable of projecting to the side of the vehicle body has been described, but the present invention is not limited to this. The outrigger beam is unnecessary if the jack device can be stably supported.

[0032]

As described above, the safety device for aerial work vehicles of the present invention detects whether or not the position of the boom is within the vehicle body stability maintaining range by means of the boom safety position detecting means, and maintains the vehicle stability in the vehicle body. The jack operation permitting means is configured to allow the jack operation means to store the jack device only when it is detected that the jack device is within the range. Here, the vehicle body stability maintaining range is a range where the vehicle body can be stably supported by the wheels without grounding the jack device, and when the position of the boom is within the vehicle body stability maintaining range, the jack device does not need to be grounded. Since the vehicle body does not become unstable, the jack device can be stored even when the boom is not in the storage position, and the vehicle body can be driven in a stable state without any change.

Further, when the boom is within the vehicle body stability maintaining range excluding the stowed position, the jack operation permitting means performs a temporary storage operation for raising the jack device by a predetermined amount from the contact state of the jack device. In the case of the safety device for the work vehicle, the predetermined amount to raise the jack device is
By setting the minimum amount of climb that allows the vehicle body to travel, it is possible to reduce the time from when the jack device is in contact with the ground to when the vehicle body travels when the jack is housed and the vehicle travels during work.

Further, only when the grounding operation of the jack is detected by the grounding detecting means for detecting the grounding operation of the jack device, the boom operation permitting means permits the operation of the boom out of the vehicle body stable support range. In such a safety device for an aerial work vehicle, the operation of a boom that makes the vehicle body unstable if the jack device is not grounded is regulated, so that the stability of the vehicle body can be ensured.

In a safety device for an aerial work vehicle in which a worktable on which a worker can be mounted is provided at the end of the boom and jack operating means is provided on the worktable, the boom supports the vehicle body stably. When it is within the range, the worker on the work table can control the storage operation of the jack device, so that quick work can be performed even when the vehicle body is run.

If the detection of the vehicle body stability maintaining range by the boom safe position detecting means is performed based on the boom state, the vehicle body stability maintaining range is detected by a relatively simple detector configuration. be able to. In addition, when the vehicle body stability maintaining range is to be detected based on the boom moment, even if the load at the boom tip changes or the position of the workbench or the like at the boom tip changes, appropriate The operation of the boom and jack device can be controlled.

[Brief description of the drawings]

FIG. 1 is a side view showing an example of work by an aerial vehicle equipped with a safety device for an aerial vehicle according to the present invention.

FIG. 2 is a side view illustrating another working example of the aerial work vehicle.

FIG. 3 is a perspective view of the aerial work vehicle;

FIG. 4 is a block diagram of the safety device for the aerial work vehicle.

FIG. 5 is a side view showing a boom operation range of the aerial work vehicle.

FIG. 6 is a side view showing another example of the aerial work vehicle according to the present invention.

[Explanation of symbols]

 1,40 Aerial work platform 2,42 Boom 3,43 Work table 4,44 Body 5,45 Swivel table 10 Jack device 31 Messenger wire 32 Hanger 33 Electric wire

──────────────────────────────────────────────────続 き Continued from the front page (56) References JP-A-61-18700 (JP, A) JP-A 4-127800 (JP, U) JP-A 62-89289 (JP, U) JP-A 62-89289 108395 (JP, U) Hikaru 2-33768 (JP, U) (58) Fields surveyed (Int. Cl. ⁷ , DB name) B66F 9/06-9/24

Claims (4)

(57) [Claims] 1. A vehicle body having wheels and capable of traveling, a boom which can be stored on the vehicle body while falling down, and which is arranged so that at least the up-and-down operation can be freely performed from the stored position. It is provided on the vehicle body so that it can be grounded and stored freely,
A jack device for supporting the vehicle body by grounding, a jack operating means for controlling the grounding and storing operation of the jack device, and maintaining a predetermined vehicle body stability in a state where the jack device is stored and the wheels are grounded Boom safety position detection means for detecting whether the position of the boom is within the vehicle body stability maintaining range, and detecting that the boom position is within the vehicle body stability maintaining range. And a jack operation permitting means for permitting the jack device to be housed by the jack operating means only when detected by the means. 2. The storing operation includes a complete storing operation for completely storing the jack device, and a temporary storing operation for raising the jack device by a predetermined amount from a grounded state of the jack device. The aerial work vehicle according to claim 1, wherein the jack operation permitting means is configured to perform the temporary storage operation when the vehicle is within the vehicle body stability maintaining range excluding the storage position. Safety device. 3. A ground detecting means for detecting a ground operation of the jack device, and only when the ground operation of the jack is detected by the ground detecting means, the operation of the boom out of the vehicle body stability maintaining range is permitted. The safety device for an aerial work vehicle according to claim 1 or 2, further comprising a boom operation permitting means. 4. The work platform according to claim 1, wherein a work table on which a worker can ride is provided at a tip of the boom, and the jack operating means is provided on the work table. Safety equipment for aerial work vehicles.