JP2001010798A - High lift work vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a high lift work vehicle with a highly precise load detector. SOLUTION: This high lift work vehicle includes a supporting member 10 disposed between a boom and a working table 6, supported so as to be freely oscillated around a first rotation supporting point 11 and pivotally supported on the boom so as to be freely oscillated around a second rotation supporting point 12, a first moment detecting means 21a for detecting a moment M1 effected by the working table 6 around the first rotation supporting point 11, a second moment detecting means 22a for detecting a moment M2 effected by the supporting member around the second rotation supporting point, a storage means for storing a horizontal distance L between the first rotation supporting point 11 and the second rotation supporting point 12 and a computing means. The computing means calculates a working table load from the moment M1 around the first rotation supporting point, the moment M2 around the second rotation supporting point and the horizontal distance L between two rotation supporting points.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a boom having at least an up-and-down movement on a vehicle body. The present invention relates to a boom type aerial work vehicle that moves to a desired height to perform work, and more particularly to a load detection device that detects a load acting on a work table of the work vehicle.

[0002]

2. Description of the Related Art A boom provided on a vehicle body to freely move up and down, turning, and expanding and contracting, and a workbench provided at the tip of the boom and constantly leveling regardless of the boom angle. Boom type aerial work vehicles that move the workbench to a desired height by operating the boom such as telescopic movement, undulating movement, turning movement, etc. are used for power distribution work, construction work, aircraft and ships It is widely used for manufacturing and maintenance work.

In the aerial work vehicle as described above, the moment acting on the boom increases due to the load of the load loaded on the work table and the operation of a work device such as a winch disposed near the work table. A load detecting device for detecting a load applied to the boom so that the load applied to the boom and the operating device of the boom are not damaged by the load applied to the boom. Some devices are configured to restrict the operation of the boom when it is determined that the load detected by the device exceeds a predetermined load.

[0004]

However, the conventional load detecting device detects a boom up / down angle and an extension amount, a turning angle with respect to the vehicle body, and the like, and calculates a position of the workbench. An axial force detector for detecting a load (axial force) acting in the operating axial direction of an up-and-down cylinder arranged between the base end boom and operating the boom to raise and lower the boom; By calculating the moment acting on the boom, that is, the supporting moment of the boom, and dividing the supporting moment of the boom by the horizontal distance (working radius) from the center of the swivel table, which is the arm length of the moment, to the work table. And the load acting on the boom tip, that is, the workbench load, has been determined.

[0005] Alternatively, in order to improve the detection accuracy of the work table load, an axial force detector for detecting an axial load (axial force) acting on a swing cylinder that always keeps the work table horizontal is provided. The work platform load is calculated by calculating the moment acting on the tip from the work table, that is, the work table support moment, subtracting the work table support moment from the boom support moment, and dividing this by the work radius. Was.

For this reason, when the working radius is large, the denominator of the above formula is large and the calculated load error is small. However, when the working radius is small, the denominator of the calculated formula is small. Therefore, there is a problem that the smaller the working radius, the worse the load detection accuracy becomes. In particular, in a high-load-load type boom work vehicle equipped with a large work table and capable of simultaneously transporting a plurality of workers and work materials to an arbitrary height, the numerator of the above calculation formula is smaller than that of other work vehicles. Since the size of the load becomes remarkably large, a high-precision load detecting device has been demanded in view of both ensuring work safety and protecting a vehicle structure.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and has been made in order to meet the demand. The present invention has a load detecting device for detecting a work table load acting on a boom with high accuracy, thereby enhancing safety at a high place. The purpose is to provide a car.

[0008]

In order to achieve the above object, according to the present invention, there is provided a boom provided at least on a vehicle body so as to be able to move up and down, and a boom provided at a tip end of the boom and having an angle of elevation of the boom. An aerial work platform having a worktable whose floor surface is always kept horizontal regardless of the height of the workbench, which is disposed between the boom and the worktable, and has a first rotation fulcrum (for example, in the embodiment) in a vertical plane. And the boom is pivotally supported on the worktable about a connection pin 11) at the center, and the boom is about a second rotation fulcrum (for example, the swing connection shaft 12 in the embodiment) in a vertical plane. A support member pivotally supported on the first stage, first moment detecting means for detecting a moment acting from the work table around the first rotation fulcrum (for example, a work table support moment detection device 21 in the embodiment), The second time In the boom acts on the second moment detection means (e.g., the embodiment for detecting a moment acting from the supporting member around the fulcrum moment detecting apparatus 2
2), storage means for storing the horizontal distance between the first rotation fulcrum and the second rotation fulcrum (for example, the memory 31 in the embodiment), and the detected moment acting around the first rotation fulcrum and the moment acting around the first rotation fulcrum. A calculating means (for example, the processing unit 32 in the embodiment) for calculating the work platform load from the moment acting around the second rotation fulcrum and the stored horizontal distance between the first rotation fulcrum and the second rotation fulcrum ) To constitute an aerial work vehicle.

According to the above construction, the support member is swingably supported by the worktable about the first rotation fulcrum, and is pivotally supported by the boom about the second rotation fulcrum. . Then, a moment acting on the boom around the first rotation fulcrum (hereinafter referred to as “workbench support moment”) and a moment acting on the boom from the support member around the second rotation fulcrum (hereinafter “boom acting moment”) ) And the horizontal distance between the two rotation fulcrums on which these moments act, the load acting on the boom from the workbench (referred to as “workbench load”) is calculated by the calculating means.

More specifically, the difference between the work platform support moment and the boom acting moment is determined, and the difference is determined by the distance between the acting points of the two moments (ie, the distance between the two rotating fulcrums).
Is obtained by an arithmetic expression having a basic configuration of dividing by. According to such a method, the horizontal distance between the two rotation fulcrums, which is the denominator of the arithmetic expression, is determined by the boom posture (boom up / down angle, swing angle, extension amount, etc.) as in the working radius used in the prior art. ) Does not change. Therefore, the workbench load can be detected with high accuracy regardless of the boom posture. In addition,
The moment around each rotation fulcrum is calculated by using a rod or a plate as a rotation fulcrum and using a twist or bending (distortion), in addition to a method using a load detecting means described in detail later. There is a method of calculating from a relative displacement amount between the worktable and the support member caused by the deformation of the member.

It is preferable that the rocking surface (the vertical surface) having the first pivot point as the center of rotation is a surface (vertical surface) parallel to the undulating surface of the boom, including the undulating surface of the boom.
According to such a configuration, since the two moments act in the same plane or in a parallel plane, there is no need to calculate the angular component force of the moment due to the difference in the acting surface angles of the two moments. It is possible to detect the work platform load with high accuracy by simplifying the operation formula of the work platform load.

The support member for supporting the worktable is a shaft support member (for example, the connecting pin 11 in the embodiment) for swingably supporting the worktable in a vertical plane about a first rotation fulcrum. And at a predetermined distance from the shaft support member, regulates the swing between the support member and the worktable, and
A first load detecting means (for example, a workbench load detector 21a in the embodiment) for detecting a load acting on the supporting member from the workbench with the rotation fulcrum as a swing center; Preferably, a moment around the first rotation fulcrum is calculated by calculating a product of the detected value and the predetermined distance based on a detected value from the first load detecting means.

According to such a configuration, even in a high-load aerial work vehicle having a large work table area and a large load weight, the work table can be stably supported, and the size and load of the work table can be increased. The distance between the shaft support member and the first load detecting means can be appropriately set according to the load, or a load detector adapted to the setting can be easily selected, and a highly accurate and stable first moment detecting means can be provided. Can be easily obtained.

Further, the second moment detecting means includes a second moment detecting means.
Second load detecting means (for example, an axial force detector 22a in the embodiment) for detecting a load in the direction of the operating axis of the swing cylinder for swinging the worktable about the rotation fulcrum of the work table; It has a distance detecting means (for example, an undulation angle detector 22c and an arithmetic circuit 22b in the embodiment) for detecting a normal distance of the oscillating cylinder to the operating axis, and detects a value detected by the second load detecting means and distance detection. It is preferable to calculate a moment around the second rotation fulcrum from a value detected by the means.

Among the moment detecting means, the second load detecting means for detecting a load in the operating axis direction of the swing cylinder includes, for example, a load cell built in a pivot pin for pivotally connecting the swing cylinder to a boom or a support member. An axial force detector that calculates the axial load by detecting the distortion of the pin is already widely used, and can be easily applied. The normal distance from the second rotation fulcrum to the operating axis of the oscillating cylinder is such that the positional relationship between the second rotation fulcrum and the pivot pin of the oscillating cylinder is determined geometrically, and Can be calculated, for example, by detecting the boom undulation angle or the relative angle between the boom and the support member, since the leveling mechanism of the aerial work vehicle constantly maintains the horizontal. Therefore, according to such a configuration, the second moment detecting means can be easily configured without largely changing the configuration of the aerial work vehicle.

The aerial work vehicle has a display means (for example, the display device 40 in the embodiment), and the storage means stores the weight of the worktable in a preset manner.
It is preferable that the calculating means calculates the load weight on the workbench from the calculated workbench load and the stored workbench weight and displays the weight on the display means. In other words, the calculating means subtracts the weight of the work table itself from the work load acting on the boom including the work table, and calculates the load on the work table by performing desired correction as necessary. It is displayed by the display means. For this reason, the worker can know during the loading operation whether the material or the like loaded on the workbench is less than the allowable load of the aerial work vehicle or how much more can be loaded. Therefore, after loading the materials using the eye check account, while moving the work table to a higher place, the operation of the boom is restricted by the overturn prevention device, etc., and the redo work such as returning to the original position and lowering the load is performed beforehand. Can be prevented.

The storage means has preset and stored an allowable load of the worktable, and the arithmetic means compares the calculated worktable load with the allowable load, and calculates the worktable load as an allowable load. It is desirable to perform an alarm operation when it is determined that the time has been exceeded. According to such a configuration, in the same manner as described above, the worker can know whether the material or the like loaded during the loading operation is the allowable load of the aerial work vehicle, and can load the material or the like exceeding the loading load. Unsafe acts can be prevented beforehand and a safe work platform can be provided.

The worktable is configured to be rotatable with respect to the support member in a horizontal plane, and the center axis of the swivel movement (for example, the swivel center axis 60 in the embodiment) is defined by the first rotation fulcrum and the first rotation support point. It is desirable to be provided in the middle of the load detecting means. In such a configuration, the driving device required for the turning operation can be disposed inside the support member, so that space can be effectively used, and the rotation center of the turning motion is the first rotation fulcrum. And the first load detecting means, the amount of change in the workbench support moment detected even when the workbench is swiveled is suppressed to a small value. You can get a working vehicle.

[0019]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below with reference to the drawings. First, FIG. 3 shows a side view of an aerial work vehicle 1 provided with a boom operation control device according to the present invention, and the configuration of the aerial work vehicle 1 will be described. The aerial work vehicle 1 is configured with a truck as a base, and a swivel 3 is attached to the rear of the body 2 so as to be horizontally swingable with respect to the body 2 by a swing motor (not shown). The boom 4 is pivotally attached to the vehicle body 2 so as to be able to move up and down by the expansion and contraction operation of the up and down cylinder 51. The boom 4 includes a base boom 4a pivotally attached to the swivel 3 and an intermediate boom 4b and a distal boom 4 telescopically inserted into the base boom 4a.
c, and a telescopic cylinder disposed inside the boom 4
It is configured to be extendable and retractable with respect to the base end boom 4a by an extension and contraction operation (not shown).

A work table (work floor) 6 is attached to the tip of the boom 4 via a support member 10 so as to be swingable in a vertical plane substantially the same as the up-and-down angle plane of the boom 4.
Is configured to be rotatable 360 degrees with respect to the support member 10 in a horizontal plane by a worktable rotation motor (not shown).
In addition, between the work table 6 and the tip boom 4c, a leveling device (not shown) operates in conjunction with the expansion / contraction operation of the up / down cylinder 51, and the floor surface of the work table 6 is raised regardless of the up / down angle of the boom 4. A leveling cylinder 52 is provided to keep the horizontal level at all times.

The boom 4 is swung in front, rear, left and right of the vehicle body 2.
In order to stably support the vehicle body 2 against the overturning moment acting in the direction in which the vehicle body is to be overturned by acting on the vehicle body when the up-and-down motion, the extension motion, etc. Outrigger jacks 8, 8 that are configured to be freely grounded are provided.

In the aerial work vehicle configured as described above,
An operator riding on the work table 6 operates the upper boom operation device 7a provided on the work table, or an operator on the ground side operates the lower boom operation device 7b provided on the vehicle body 2 side. By operating the boom operating means such as the swing motor, the up-and-down cylinder 51, and the telescopic cylinder, the workbench 6 is moved to a desired height by causing the boom 4 to pivot, raise and lower, extend and retract, and the like. Work can be done.

FIG. 1 shows the tip boom 4 of this aerial work vehicle.
c and the connecting portion of the worktable 6 (I shown by a dashed line in FIG. 3)
The worktable 6 is pivotally attached to the distal end boom 4c by a swing connection shaft 12 via a support member 10, and its operation is controlled by a leveling device (not shown). By the expansion and contraction operation of the swing cylinder 52, the floor surface of the worktable 6 is always kept horizontal irrespective of the elevation angle of the boom 4.

The work table 6 is connected to a connecting base 6a connected to the support member 10 and a central portion of the floor 6c of the work table 6 disposed above the connecting base 6a.
The work table 6 is rotated 36
It is configured to have a swivel 6b for horizontally turning by 0 degrees.

The connection base 6a of the worktable 6 is connected to the support member 10 by a connection pin 11 extending in a direction perpendicular to the plane of the drawing, and is substantially flush with the boom's undulating surface (parallel surface including the undulating surface).
It is pivotally supported inside. In addition, connection base 6a
The swing is connected to the support member 10 by the worktable load detector 21a disposed at a position apart in the direction by a distance l ₁ perpendicular to the connecting pin 11 is restricted, the worktable load detector 21a connecting pin A load acting on this detector is detected around 11. Note that a pin-type load cell can be used as such a load detector.

The support member 10 is pivotally attached to the distal end of the tip boom 4c by a swing connection shaft 12, and both ends 13, 14 are pivotally supported between the support member 10 and the tip boom 4c. The telescopic operation of the double-headed clevis type swing cylinder 52 causes the tip boom 4c to swing (leveling operation). The tube-side connection pin 14 (or the rod-side connection pin 13) of the oscillating cylinder 52 is provided with an axial force detector 22a that detects an axial load acting on the cylinder in the operation axis direction.

Now, in the work table support structure configured as described above, the load detected by the work table load detector 21a is a load acting from the work table with the connecting pin 11 as the center of rotation. moment the product of the arm length l ₁ that acts as a load f ₁ is applied around the connecting pin 11, that is, the worktable supporting moment M _1.
The load detected by the axial force detector 22a is a load applied from the support member to swing the connecting shaft 12 as a rotation center, arm length acting as the detected load f ₂ (i.e. swing cylinder 52 moment the product of the perpendicular distance) l ₂ between the actuating shaft and the reciprocating connecting shaft 12 is applied around the rocking connecting shaft 12 via the supporting member 10, i.e. a boom acting moment M _2.

The normal distance l ₂ between the operating shaft of the oscillating cylinder 52 and the oscillating connecting shaft 12 is determined by the relative angle between the tip boom 4 c and the support member 10 which changes in accordance with the up-and-down angle of the boom 4. It changes little by little. However, since the work platform 6 of the aerial work platform is always kept horizontal by the leveling mechanism, these relationships are determined by detecting the undulation angle of the boom 4 or the relative angle between the boom 4 and the support member 10. It can be calculated by scientific calculation. In the present invention, detected by derricking angle detector 22c disposed in the boom 4, an arithmetic circuit 22b to be described later to calculate the perpendicular distance l _2, calculates a boom moment acts M ₂ around the reciprocating connecting shaft 12 An example will be described.

In the above-described support mode, the total load (work table load) acting on the work table 6 including the structural weight of the work table itself is represented by W, and the connection pin 11 and the swing connection shaft 1
Considering the balance of the moment around the swing connection shaft 12 when the horizontal distance to L is L,

[0030]

M ₁ + WL = M _{2 From} this, W = (M ₁ −M ₂ ) / L (1)

Here, the connecting pin 11 in the above basic formula is used.
The horizontal distance L between the swinging connection shaft 12 and the swing connection shaft 12 does not change since the work table 6 is always kept horizontal, and is a constant determined in terms of structure. Therefore, by detecting the _two moments M ₁ and M ₂ by the above method, it is possible to calculate the total load acting on the boom from the work table, that is, the work table load. Then, the work table 6 known from the work table load W
By subtracting the structural weight Ww, the weight of the material loaded on the work table 6, that is, the loaded weight Ws can be calculated.

FIG. 3 is a block diagram showing the configuration of the load detecting device 100 using the above-described load detecting method. The operation of the load detecting device 100 will be described below with reference to FIG. The load detection device 100 includes a work platform support moment detection device 21 that detects the work platform support moment M _1.
, A boom moment detecting device 22 for detecting a boom acting moment M ₂ , a controller 30 for calculating a workbench load and the like, and a display device 40 for displaying a loaded load and the like.

The workbench support moment detecting device 21 includes a workbench load detector 21a and an arithmetic circuit 21b provided on the support member 10, and the arithmetic circuit 21b.
Is the work platform support moment M around the connection pin 11 from the detection value f _{1 of} the work platform load detector 21a and the distance l ₁ between the work table load detector 21a and the connection pin 11 stored in advance in an internal memory. ₁ is calculated by a calculation formula M ₁ = f ₁ × l ₁ and output to the controller 30.

The boom acting moment detecting device 22 includes an axial force detector 22a provided on a pivot pin of the swing cylinder.
, An up-and-down angle detector 22c provided on the boom, and an arithmetic circuit 22b. The arithmetic circuit 22b detects the boom 4 and the support member 10 based on the up-down angle of the boom 4 detected by the up-down angle detector 22c. Is calculated, and the undulation angle detector 22a at this relative angle is calculated.
A normal distance l ₂ between the axis of rotation of the oscillating cylinder 52 and the oscillating shaft 12 is calculated, and the calculated value l ₂ and the axial force detector 22 are calculated.
and outputs to the controller 30 is calculated by the calculation formula M ₂ = f ₂ × l ₂ the boom moment acts M ₂ around the detection value f ₁ Tokara reciprocating connecting shaft 12 by a.

The controller 30 is configured to have a memory 31 therein and processor 32, processor 32 worktable supporting moment M ₁ and the boom input is calculated as described above Acting moment M ₂ ,
The worktable load W is calculated from the horizontal distance L between the connecting pin 11 and the swing connecting shaft 12 stored in the memory 31 by the above-described equation (1).

The arithmetic processing unit 32 subtracts the structural weight (whole weight of the work table 6 when there is no load) Ww of the work table 6 previously set and stored in the memory 32 from the calculated work table load W. The controller 30 obtains the weight (load weight) Ws of the load loaded on the worktable 6 by processing, and the controller 30 transfers the weight Ws to the display panel or the boom 4 provided in the operation devices 7a and 7b of the boom, for example. The display device 40, such as a load factor display lamp, displays a numerical value, an LED bar, a lamp, or the like.

The controller 30 includes the arithmetic processing unit 3
When it is determined that the platform load W calculated in Step 2 exceeds the allowable load set and stored in the memory in advance (or when it is determined that the calculated load exceeds the allowable load), An alarm is displayed by an alarm lamp, an alarm buzzer, or the like, and an alarm signal is output to the boom operation control device 50 to perform an alarm operation such as regulating the operation of the boom.

For this reason, in the aerial work vehicle constructed as described above, the operator who gets on the work table can load materials and the like on the work table 6 by the display device 40 provided on the work table. The load of materials and the like loaded during the work can be known, and when the load of the work table exceeds the allowable load due to the load, this can be recognized by an alarm operation.

Although the basic operation formula of the work platform load has been described above for the sake of simplicity, the accuracy can be further improved by adding a variable. For example, the boom support moment M ₂ to be detected around the swinging rotary shaft 12 in the basic formula is included incremental M _alpha moment due to the weight of the support member 10, furthermore, the increment M _alpha in this moment boom It is a factor of error because it changes depending on the undulation angle of However, the incremental M _alpha of the moment can be defined in relation to the derricking angle. Thus, for in M ₂ to the basic formula described above, it is possible to correct the moment the derricking angle and variable, thereby, it is possible to perform further accurate load calculations.

Further, in the present embodiment, an example in which a value detected by the boom angle detector 22c is used to calculate the normal distance l ₂ from the swing connection shaft 12 to the operating shaft of the swing cylinder 52. As described above, for example, a relative angle detector (22d in FIG. 1) for detecting the relative angle between the support member 10 and the tip boom may be used as described above, or the extension amount of the swing cylinder 52 or the rod may be used. End 13 and swing connection shaft 1
The distance between the fulcrum and the fulcrum 2 may be detected and geometrically calculated from the distance. Further, in order to detect a load acting on the operating axis of the swing cylinder, an axial force detector 2 is provided.
Although 2a is used, for example, it may be configured by calculating from the hydraulic pressure acting on the tube side (bottom side) oil chamber of the swing cylinder.

In the above description, a so-called high-loading aerial work vehicle having a large work table area and a large loading weight has been described as an example, but the present invention is limited to this embodiment. However, the size of the work table does not matter if it is a high work vehicle having at least a boom that can move up and down. For example, the present invention is also applicable to an aerial work vehicle having a so-called bucket or an articulated aerial work vehicle having a bending / extending arm.

[0042]

As described above, in the present invention, the work table is provided between the boom and the work table, and is swingably supported on the work table about the first rotation fulcrum in a vertical plane. A support member pivotally supported by the boom about a second rotation fulcrum in a vertical plane, and a first work platform support moment detected from the work table around the first rotation fulcrum. Moment detecting means, and second moment detecting means for detecting a boom acting moment acting on the boom from the support member around the second rotation fulcrum;
A storage means for storing a distance between the first rotation fulcrum and the second rotation fulcrum; and a calculation means for calculating a work platform load from the detected two moments and the stored distance between the fulcrum. The work vehicle is constructed. According to such a configuration, the horizontal distance between the two rotation fulcrums serving as the denominator of the arithmetic expression does not change depending on the boom posture. Therefore, the workbench load can be detected with high accuracy regardless of the boom posture.

It is preferable that the swing surface (vertical surface) having the first rotation fulcrum as the center of rotation is a surface (vertical surface) parallel to the boom undulation surface including the boom undulation surface. According to such a configuration, there is no need to calculate the angular component force of the moment due to the difference in the acting surface angle of the moment. Therefore, the operation formula of the platform load is simplified and the platform load is detected with high accuracy. can do.

The support member for supporting the worktable includes a support member for pivotally supporting the worktable around the first rotation fulcrum, and a support member disposed at a predetermined distance from the support member. And first load detecting means for restricting the swing between the work table and the work table, and detecting a load acting on the support member from the work table with the first rotation fulcrum as the swing center. Preferably, the moment around the first rotation fulcrum is calculated based on the detection value from the first load detection means. According to such a configuration, the distance between the shaft support member and the first load detecting means can be appropriately set according to the size of the worktable and the load to stably support, and high accuracy and stability can be achieved. The obtained first moment detecting means can be easily obtained.

The second moment detecting means includes a second load detecting means for detecting a load in the direction of the operating axis of the swing cylinder for swinging the worktable about the second rotation fulcrum, and the second rotation fulcrum. A distance detecting means for detecting a normal distance of the oscillating cylinder to the operating shaft, wherein a moment about the second rotation fulcrum is calculated from a value detected by the axial force detecting means and a value detected by the distance detecting means. Is preferred. According to such a configuration, the second moment detecting means can be easily configured without largely changing the configuration of the aerial work vehicle.

The high work vehicle has display means, and the calculating means calculates the load weight on the work table from the calculated work load and the stored work table weight, and displays the weight on the display means. Further, it is preferable that the calculating means compares the calculated work platform load with the allowable load and performs an alarm operation when it is determined that the work platform load exceeds the allowable load. With such a configuration, the worker can know during the loading operation whether or not the material or the like loaded on the workbench is less than the allowable load of the aerial work platform and the remaining loadable weight. Therefore, it is possible to perform the work efficiently by preventing the reworking operation, and to provide a safe aerial work vehicle by preventing unsafe acts such as loading exceeding the load.

The working table is preferably configured to be pivotable in a horizontal plane with respect to the support member, and the center axis of the pivoting operation is preferably disposed between the first rotation fulcrum and the first load detecting means. . In such a configuration, the driving device required for the turning operation can be placed inside the support member, so that the space can be effectively utilized, and the workbench support detected even when the workbench is swung. It is possible to obtain an aerial work vehicle equipped with a high-precision load detecting device by suppressing the amount of change in moment to be small.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram for explaining a workbench support portion of a boom working vehicle according to the present invention.

FIG. 2 is a block diagram illustrating a configuration of a load detection device for the boom working vehicle.

FIG. 3 is a side view showing the entire boom working vehicle according to the present invention.

[Explanation of symbols]

1 Boom work vehicle 2 Body 4 Boom (4a base end boom, 4b end boom, 4 boom
c tip boom) 6 worktable 10 support member 11 connection pin (first rotation fulcrum, shaft support member) 12 swing connection shaft (second rotation fulcrum) 21 worktable support moment detection device (first moment detection means) 21a Workbench load detector (first load detecting means) 22 Boom acting moment detecting means (second moment detecting means) 22a Axial force detector (second load detecting means) 22b Arithmetic circuit (distance detecting means) 22c Undulation angle detection Device (distance detecting means) 22d relative angle detector (distance detecting means) 30 controller 31 memory (storage means) 32 arithmetic processing unit (calculating means) 40 display device (display means) 52 leveling cylinder (oscillating cylinder) 60 work bench Axis of rotation (center axis of rotation)

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) B66F 11/04 B66F 11/04

Claims (5)

[Claims] 1. A boom provided at least on a vehicle body so as to be able to move up and down, and a work provided at a tip end of the boom so that a floor surface is always kept horizontal regardless of the boom angle. A work platform for moving the work table to an arbitrary height, the work table being arranged between the boom and the work table, and a first work vehicle in a vertical plane. A support member pivotally supported by the worktable about a rotation fulcrum and pivotally supported by the boom about a second rotation fulcrum in a vertical plane; and the first rotation First moment detecting means for detecting a moment acting from the worktable around a fulcrum; second moment detecting means for detecting a moment acting from the support member around the second rotation fulcrum; the first rotation Fulcrum and the second Storage means for storing a horizontal distance from a rotation fulcrum; a moment acting around the detected first rotation fulcrum and a moment acting around the second rotation fulcrum; and the stored first rotation fulcrum. And a calculating means for calculating a workbench load from a horizontal distance between the second rotating fulcrum and the second rotating fulcrum. 2. A supporting member for pivotally supporting the work table in a manner about a first rotation fulcrum in the vertical plane, and a supporting member disposed at a predetermined distance from the supporting member. And a first load detecting means for restricting swinging of the support member and the worktable and detecting a load acting on the support member from the worktable with the front first fulcrum as a swing center. The high-altitude work according to claim 1, wherein the first moment detecting means calculates a moment around the first rotation fulcrum based on a detection value from the first load detecting means. car. 3. A second moment detecting means for detecting a load acting on an operating axis of a swing cylinder for swinging the worktable about the second rotation fulcrum.
Load detecting means, and distance detecting means for detecting a normal distance from the second rotation fulcrum to the operating axis of the oscillating cylinder, wherein the detected value by the second load detecting means and the distance detecting means The aerial work vehicle according to claim 1 or 2, wherein a moment about the second rotation fulcrum is calculated from the detected value. 4. The work platform aerial vehicle has display means, wherein the weight of the work table is preset and stored in the storage means, and the calculation means is the calculated work table load. 4. The load weight on the work table is calculated from the stored work table weight and the stored work table weight, and the display unit displays the calculated load weight. The aerial work vehicle described in the section. 5. The storage means stores in advance a permissible load of the workbench, and the computing means compares the calculated workbench load with the permissible load, and calculates the permissible load. The aerial work vehicle according to any one of claims 1 to 4, wherein a warning operation is performed when it is determined that the work platform load exceeds the allowable load.