JP3117902B2 - Work range control device for aerial work vehicles - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a self-propelled vehicle body,
The present invention relates to an aerial work vehicle and the like, which are configured by disposing a boom capable of operating up and down.

[0002]

2. Description of the Related Art In general, an aerial work vehicle is provided with a boom capable of turning, raising and lowering, expanding and contracting, and the like, on a freely movable vehicle body, and a work table is provided at a tip of the boom. In the work using such an aerial work vehicle, after operating the boom and moving the work table to an arbitrary high position, a worker on the work table performs a desired work.

[0003] In such an aerial work vehicle,
A moment (hereinafter, referred to as “overturning moment”) acting to overturn the vehicle body acts in a direction from the vehicle body to the position of the worktable. When the work table is moved to a desired high position, the overturning moment changes according to the extension operation of the boom and the like. In order to stably support the vehicle body against such a falling moment, jack devices that support the vehicle body with respect to the ground and stabilize the vehicle body are arranged on the front, rear, left and right of the aerial work vehicle. General.

Here, in order to prevent the falling moment, which varies according to the operation of the boom, from threatening the stability of the vehicle body, the operation of the boom is restricted within a certain range in each state, such as when the jack is touched, to prevent the vehicle from tipping over. This is common. As such a fall prevention means, there is an operation range regulation that permits the operation of the boom within a predetermined boom operation range so that the overturning moment does not exceed an allowable value, and regulates the operation of the boom beyond this range.

[0005] As a conventional means for preventing overturning, there is also a means for measuring the actual workbench load to obtain an overturning moment and regulating the overturning moment so as not to exceed a predetermined value. Boom up / down, telescopic operation, etc. are regulated so that the load on the workbench provided at the tip, that is, the overturning moment, which varies according to the weight difference of the workers and the loaded tools, etc., does not exceed the allowable value. doing. That is, the operating range of the boom is regulated according to the load of the worktable.

[0006]

By the way, in the conventional aerial work platform, when the work table is inclined, an accurate vertical load value on the work table cannot be obtained, so that the measured load smaller than the actual load is obtained. Boom operation was restricted within the working range according to the value. For this reason, even if the boom operation is restricted within the working range corresponding to the measured load value, the overturning moment may exceed a predetermined value, and the stability of the vehicle body may be impaired. Furthermore, if the load detector on the workbench breaks down, it will not be possible to select the correct working range corresponding to the loaded load, so the operation of the boom will not be regulated as intended, Threatened stability.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and has been made in view of the work of an aerial work vehicle in which the stability of a vehicle body is not impaired due to tilting of a work table or malfunction or breakage of a load detector. It is intended to provide a range control device.

[0008]

In order to achieve the above object, a work range restricting device for an aerial work apparatus according to the present invention is provided with a boom having a freely movable up and down, telescopic operation and the like on a vehicle body. A workbench disposed at the end of the boom for boarding the worker, load detecting means for detecting an actual load applied to the workbench, and detecting a position of the workbench by detecting an operation amount of the boom Based on platform position detection means and data of multiple work areas corresponding to multiple loads that define the movable range of the platform according to the load applied to the platform and a reference load smaller than the maximum allowable load that can be applied to the platform Storage means for storing data of a reference work range that defines a movable range of the work table, and an operation of the boom, wherein the actual work table position obtained by the work table position detection means exceeds the reference work range, and load Configured with an actuating regulating means for regulating the operation of the boom exceeds a load corresponding working range corresponding to the actual load detected by the load detection means of the 応作 industry range.

In this case, the reference working range is set so that the stability against the overturning moment acting on the vehicle body exceeds 1.0 when the work table is moved with the maximum allowable load applied. Is done. That is, the reference work range is the movable range of the work table when a reference load smaller than the maximum allowable load is applied to the work table, but the work table with the maximum allowable load applied is within the reference work range. This is a range in which the stability becomes 1.0 or more even when moved.

[0010]

According to the working range control device for an aerial work vehicle of the present invention, the actual load applied to the workbench is detected by the load detecting means, and the position of the worktable at the end of the boom is obtained by the workbench position detecting means. Can be The operation restricting means restricts the boom operation in which the obtained actual worktable position exceeds a load corresponding work range corresponding to the actual load detected by the load detecting means, and the actual worktable position is out of the reference work range. It also regulates the operation of the boom that exceeds.

The provision of the reference work range allows the actual work table position to be compared with the reference work range even when accurate load detection cannot be obtained by the load detection means and regulation based on the work table load cannot be performed. Therefore, at least the operation of the boom out of the reference working range is restricted.

In the present invention, as described above, the reference work range is a movable range of the work table when a reference load smaller than the maximum allowable load is applied to the work table. When it is applied, it may occur that the load exceeds the work range corresponding to the load, but this reference work range is set to a range where the stability becomes 1.0 or more even when the maximum allowable load is applied to the work table. It is set so that the aerial work vehicle can be prevented from tipping over. In other words, even if the detection of the load detecting means becomes inaccurate, it is possible to secure operation to some extent by allowing operation within the reference work range, and the stability may fall below 1.0 within this reference work range. No safe work is possible.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows an aerial work vehicle 10 having a work range control device according to the present invention. The aerial work vehicle 10 generally includes a vehicle body, a boom, and a workbench. The vehicle body portion is mainly composed of a self-propelled vehicle body 11 having driving wheels. Outrigger jacks 15 are provided on the front, rear, left and right of the vehicle body 11 to extend and contact the ground to stably support the vehicle body 11 during work. I have.

On the vehicle body 11, a built-in motor (not shown)
A swivel 12 is provided so as to be rotatable. A boom 13 is pivotally supported at the upper end of the swivel base 12 by a support shaft 12 a, and an up-and-down cylinder 14 is fixed to the boom 13 from the swivel base 12. The boom 13 is moved by the undulating cylinder 14.
Can be moved up and down freely, and the inclination of the boom 13 is
This is detected by an undulation angle detector (not shown) provided near “a”. In addition, the boom 13 includes a proximal boom member 13.
a, the intermediate boom member 13b and the tip boom member 13c are telescopically assembled, and can be freely extended and retracted by a telescopic cylinder (not shown) arranged in the boom. The amount of expansion and contraction of the boom is detected by a length detector (not shown) provided in the boom.

A vertical post 16 is pivotally supported at the distal end of the distal boom member 13c.
Irrespective of the up-and-down state of the boom 13, it is always kept perpendicular to the ground by the leveling cylinder 17. A worktable 18 is attached to the vertical post 16 via a arm 18a so as to be horizontally pivotable. Since the vertical post 16 is always kept vertical, the bottom of the worktable 18 is always
1 and can be comfortably performed by a worker who is on the worktable 18 while performing desired work. A load cell 19 for detecting a load on the worktable 18 is provided between the hub of the vertical post 16 and the arm 18a.

At the time of working at heights using the aerial work vehicle 10, the boom 13 is turned, raised and lowered, and extended, and
8 will be moved to a desired high position. These boom operations are performed by hydraulic actuators such as a hydraulic motor and a hydraulic cylinder, and the hydraulic actuator operations are performed by controlling supply and discharge of hydraulic oil supplied from a hydraulic pump (not shown) provided in the vehicle body 11. Is being done. The supply and discharge control of the hydraulic oil is performed by operating a control valve by a boom operation control device (not shown) or the like. In order to operate the boom operation control device and the like,
A workbench-side operation unit 21 is provided on the
A vehicle body side operation unit 22 is provided on 2.

FIG. 2 is a block diagram showing the working range control device of the present invention. The length detector 3 is provided as an operation amount detecting means for detecting the operation amount of the boom.
2 and the undulation angle detector 33, and the length detector 32
Detects the extension amount of the boom 13 with the stored state of the boom 13 as the origin, and the undulation angle detector 33 detects the elevation angle of the boom 13. The position calculator 36 provided as position calculating means calculates the position of the work table 18 attached to the tip of the tip boom member 13c from the extension amount and the elevation angle, and outputs the calculated position as the actual work table position.

The load cell 19 disposed on the lower surface of the arm 18a of the work table 18 always detects the load of the work table, such as an operator, tools, and materials, as load detecting means. This detected value, that is, the actual load value, is sent to the work range data storage device 35 provided as storage means. In the memory in the work range data storage device 35, a plurality of load corresponding work range data determined for each load on the work table 18 is recorded in consideration of the stability against the overturning moment acting on the aerial work vehicle 10. Have been. Using the actual load value from the load cell 19, the work range data storage device 35 retrieves and reads out load corresponding work range data corresponding to the actual load value from a plurality of load corresponding work range data stored in the memory.

The vehicle body side operation unit 22 is provided with a reference load setting device 34.
, A reference load value smaller than the maximum allowable load value of the worktable 18 is arbitrarily determined. Using this reference load value, the work range data storage device 35 uses the plurality of load corresponding work range data recorded in the memory of the work range data storage device 35 to determine the load corresponding to the reference load value. Work range data is retrieved and read as reference work range data.

The work range data storage device 35 sends the reference work range data and the load corresponding work range data corresponding to the actual load value to a boom operation restricting device 37 provided as an operation restricting means. The boom operation restricting device 37
The boom 1 output from the position calculator 36 is added to the reference work range data and the work range data corresponding to the actual load.
3 is compared with the actual workbench position which changes momentarily during the elongating and tilting operation of the actual workbench, and the actual workbench position tries to exceed the limit line of the work range corresponding to the actual load, or the actual workbench position is out of the reference work range. When trying to cross the limit line, the boom operation control device 37 interferes with the boom operation control device 38 and controls the boom operation. Note that the regulation control unit 30 of the work range regulation device is located below the vehicle body side operation unit 22 and the vehicle body 1.
1.

FIG. 3 is a diagram showing a part of the load corresponding work range data recorded in the work range data storage device 35. The load corresponding work range corresponding to the maximum load, the reference load and the minimum load. It is shown. The working range corresponding to the maximum load is the left limit line B and the upper limit line U
And an area surrounded by the right limit line H. In addition, the load corresponding work range corresponding to the reference load, that is, the reference work range is a region surrounded by the left limit line B, the upper limit line U, and the right limit line S. Further, the work area corresponding to the minimum load is a region surrounded by the left limit line B, the upper limit line U, and the right limit line L. The left limit line B is defined by the boom 13 at the time of the maximum extension and the maximum elevation of the boom 13, and the upper limit line U is at the center of the support shaft 12 a of the swivel 12, and at the maximum extension of the boom 13. It is determined by the trajectory of the operation. Further, the right limit lines H, S and L
Are arbitrarily determined in consideration of the effects of the overturning moment, the wind, etc. acting on the aerial work vehicle 10 at each load.

Here, as an embodiment, a description will be given by setting the maximum load of the worktable at 200 kgf and the reference load at 100 kgf. First, at the beginning of the work, the reference load is 10
When set to 0 kgf, this reference load value is sent to the work range data storage
In 5, a plurality of load corresponding work range data recorded in a memory in the work range data storage device 35
Work area data corresponding to the load corresponding to kgf is read as reference work area data. This data is sent to the boom operation restriction device 37. Thereafter, the outrigger jack 15 is grounded, and the materials, tools, and the like are placed on the worktable 18, and the operator boards.

200 kg load from workers, materials, tools, etc.
f is loaded on the workbench, this load is
And sent to the work range data storage device 35. In the work range data storage device 35, load corresponding work range data corresponding to 200 kgf is read out from a plurality of load corresponding work range data recorded in a memory in the work range data storage device 35, and this data is stored in the boom operation regulation. It is sent to the device 37. When the boom 13 is raised and extended, the elevation angle of the boom 13 is detected by the undulation angle detector 33 and the extension amount is detected by the length detector 32. These detected values are sent to the position calculator 36,
Thus, the actual worktable position of the worktable arranged at the tip of the boom 13 is calculated. This calculated value that changes with the operation of the boom 13 is always output to the boom operation restricting device 37. The calculated value is always read from the working range data storage device 35 into the boom operation restricting device 37 by the comparator in the boom operation restricting device 37.
The comparison is made with the gf reference work range data and the work range data corresponding to the 200 kgf load.

Since the right limit line H of the work range corresponding to the 200 kgf load is inside the right limit line S of the 100 kgf reference work range, when the boom 13 is extended and the work table 18 is moved to a higher position, the 200 kgf The boom operation regulation due to the right limit line H of the work area corresponding to the load is received.

At this time, the work table is tilted and the load cell 19 is tilted.
It is assumed that the load detection by the load cell 19 becomes inaccurate or the load cell 19 breaks down. In this case, the load corresponding work range data corresponding to such an incorrect load detection value is read from the work range data storage device 35, and the regulation within the load corresponding work range is performed.
The workbench 18 may continue to operate beyond the desired right limit line. However, even in this case, the boom operation is restricted due to the right limit line S of the 100 kgf reference work range.
Therefore, even when the load cell 19 fails, the operation of the boom is restricted within the reference working range.
The boom operation that leads to the falling of the vehicle is prevented.

The reference load is set to 100 kgf, as described above, considering the load for at least the worker to board the work table 18.

At this time, if the working range corresponding to the load whose stability against the overturning moment at the maximum allowable load of the work table exceeds 1.0 is determined as the reference work range, that is, the work table can be moved to the standard work range with the maximum allowable load. If the stability is determined so as to exceed 1.0 when moving within the standard work range, even if the work table 18 is operated with the maximum allowable load, the load cell 19 may be damaged. By restricting the working range within the vehicle, the fall of the work vehicle at a height can be reliably avoided.

The present invention is not limited to the above embodiment. Further, a boom swing angle detector is provided to detect the swing angle, and to use the load corresponding working range data taking this swing angle into consideration. Work range regulation may be used. It is clear that further improvements, improvements, changes, etc. can be made within the scope of the claims of the present invention.

[0029]

As described above, according to the work range restricting device for an aerial work vehicle of the present invention, it is possible to restrict the operation of the boom in accordance with the load on the workbench (the work range based on the load range). In addition, the operation of the boom is regulated based on the reference working range corresponding to the reference load, and the operation of the boom is restricted within the working range corresponding to the load and within the reference working range. For this reason, even when the platform is tilted and it is not possible to accurately detect the platform load, or even when the load detection means fails and accurate detection is not possible, at least restrict the boom operation exceeding the reference working range, Safety can be improved.

Further, in the present invention, the reference working range is set to a range where the stability becomes 1.0 or more even when the maximum allowable load is applied to the workbench. The fall of the aerial work vehicle can be avoided.
In other words, even if the detection of the load detecting means becomes inaccurate, it is possible to secure operation to some extent by allowing operation within the reference work range, and the stability may fall below 1.0 within this reference work range. No safe work is possible. In addition,
This stability is more advantageous for overturn prevention as it is larger than 1.0, but since the reference work range is narrower, the stability becomes a value close to 1.0 under good environment work conditions. By setting such a reference work range, it is possible to set the work range as wide as possible while ensuring stability.

On the other hand, when taking into account the operation of the boom during the operation of the outrigger jack and the running of the vehicle body, the vehicle body is likely to become temporarily unstable, and the reference load is relatively increased while increasing the stability. By setting the weight heavier, the reference working range can be easily narrowed, and the boom operation can be restricted except for the working range where the risk of instability increases. Since the temporary instability of the vehicle body can be easily avoided in this way, the stability of the aerial work vehicle is further improved.

[Brief description of the drawings]

FIG. 1 is an overall side view of an aerial work vehicle according to the present invention.

FIG. 2 is a block diagram of a work range control device for an aerial work vehicle.

FIG. 3 is a work range diagram of an aerial work vehicle.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Aerial work vehicle 11 Body 12 Turn table 15 Outrigger jack 16 Vertical post 18 Work table 19 Load cell 32 Length detector 33 Undulation angle detector 36 Position calculator 35 Work range data storage device 37 Boom operation restriction device

Continuation of the front page (56) References JP-A 7-23795 (JP, U) JP-A 1-132700 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) B66F 9 / twenty four

Claims (1)

(57) [Claims] 1. A boom disposed on a vehicle body so as to be able to move up and down, extend and retract freely, a workbench disposed at the tip of the boom for boarding a worker, and an actual load applied to the workbench is detected. Load detecting means for detecting, a work table position detecting means for detecting a position of the work table by detecting an operation amount of the boom, and a plurality of movable ranges of the work table determined according to a load applied to the work table. Storage means for storing data of a work range corresponding to a load, and data of a reference work range that defines a movable range of the work table based on a reference load smaller than a maximum allowable load that can be applied to the work table; An actual workbench position determined by the workbench position detection means, an operation of the boom exceeding the reference work range, and an actual load detected by the load detection means in the plurality of load-responsive work ranges; An operation restricting means for restricting the operation of the boom that exceeds the corresponding load-adaptive operation range, wherein the reference operation range is a vehicle body when the work table is moved in a state where the maximum allowable load is applied. A work range restricting device for an aerial work vehicle, wherein the stability with respect to a falling moment acting on the vehicle is set so as to be in a range exceeding 1.0.