JPH0673080U - Work platform mounting structure for aerial work platforms - Google Patents

Abstract

(57) [Abstract] [Purpose] To obtain a workbench mounting structure for an aerial work vehicle that enables accurate detection of the load by the load detector provided on the vertical post. A post member 6a of a vertical post is rotatably disposed on a support pin 8 fixed between a pair of upper and lower mounting brackets 7a and 7b fixed to a work table 7. Between the upper bracket 7a and the load detector 1
1 is sandwiched and arranged. The distance from the lower surface of the upper bracket 7a to the seat surface 8b of the support pin 8 that contacts the upper surface of the lower bracket 7b is determined by the vertical thickness dimension Pt of the post member 6a and the vertical thickness dimension Lt of the load detector 11.
It is larger than the combined size of and. Accordingly, the brackets 7a and 7b are not twisted, and even if the brackets 7a and 7b are warped, the brackets 7a and 7b do not interfere with the load cell 11, so that the load of the workbench 7 can be accurately detected. .

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a workbench mounting structure for an aerial work vehicle equipped with a work range control device for a workbench attached to the tip of a boom.

[0002]

[Prior art]

 An aerial work vehicle is configured with a work platform on which a worker can ride at the tip of a boom that can be raised, retracted, swiveled, etc., and a vertical post is attached to the tip of the boom. The workbench is mounted so that it can rotate horizontally. In such an aerial work vehicle, since the moment in the falling direction applied to the vehicle body changes depending on the boom undulation, extension and contraction, turning operation, etc., the operation of the boom so that this moment exceeds a predetermined value is restricted. A work range control device is provided to ensure safe work.

In the conventional work range control device, the allowable posture position range of the boom is kept so that the moment applied to the vehicle body does not exceed a predetermined value. The allowable range) has been set in advance, and when the boom is operated, the boom operation is restricted so that the actual posture position of the boom that changes due to this operation exceeds the allowable posture position range. However, the loading capacity of the workbench changes according to the weight difference of the worker riding on it, the type of tools loaded, etc. The moment applied to the car body also changes. Therefore, a load cell is installed on the support part of the workbench in the vertical post, and the load cell detects the vertical load applied to the vertical post from the workbench and sets the allowable posture position range of the boom according to this vertical load. Is proposed. In this way, even when the load on the workbench changes, the work range can be appropriately regulated according to the change, and the work safety can be improved.

[0004]

[Problems to be solved by the device]

 However, the support of the worktable with respect to the vertical posts is performed by sandwiching the vertical posts by mounting brackets extending horizontally from above and below the worktable. Here, one end of each of these mounting brackets is fixed to the work table, and the other end is formed of a plate member that extends in the vertical direction and is provided with an insertion hole for a support pin. Therefore, an error may occur in the vertical load detected by the load cell due to warping when each mounting bracket is fixed, twisting of each mounting bracket caused by rotation of the workbench, change in the position of load applied to the workbench, etc. As a result, there was a problem that the accuracy of the work range regulation deteriorated.

The present invention has been made in view of the above problems, and provides a workbench mounting structure for an aerial work vehicle that enables accurate detection of a load by a load detector provided on a vertical post. It is an object.

[0006]

[Means for Solving the Problems]

 In order to achieve such an object, in the work platform mounting structure for an aerial work vehicle according to the present invention, the work platform mounting structure extends vertically from the work platform and vertically extends between a pair of vertically mounted mounting brackets. The post member of the vertical post is rotatably arranged on the provided support pin, and the load detector is sandwiched between the post member and the upper mounting bracket. Then, the distance from the lower surface of the upper mounting bracket to the seat surface of the support pin that abuts the upper surface of the lower mounting bracket is calculated by combining the vertical thickness dimension of the post member and the vertical thickness dimension of the load detector. Is also a large size.

[0007]

[Action]

 In the workbench mounting structure as described above, one end of the upper and lower mounting brackets is fixed to the workbench and the other end is fixed to the workbench, so the upper and lower mounting brackets may be twisted due to the load on the workbench. There is no. In addition, since there is a gap between the lower surface of the post member and the upper surface of the lower mounting bracket, even if the mounting bracket is warped during the manufacturing process, it will not interfere with the vertical post member and the vertical post will not interfere. The load cell mounted on can detect an accurate load.

[0008]

【Example】

 Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings. First, an example of an aerial work vehicle equipped with a workbench mounting structure according to the present invention will be described with reference to FIG. This aerial work vehicle has a swivel base 2 which is rotatable on a vehicle body 1, and a telescopic boom 3 is attached to the swivel base 2 so as to be capable of hoisting. The telescopic boom 3 is composed of a telescopically (nestedly) telescopically extensible base boom 3a, an intermediate boom 3b and a tip boom 3c. The base boom 3a is pivoted on the swivel base 2 via a support shaft 2a. It is supported and can be undulated. The telescopic boom 3 is telescopically operated by a telescopic cylinder (not shown) provided inside, and the hoisting cylinder 4 is provided between the swivel base 2 and the base end boom 3a.

A vertical post 6 is attached to the tip of the tip boom 3c so as to be swingable up and down and pivotally supported by a pin 3d. The vertical post 6 has a post member 6a, and a pair of upper and lower mounting brackets 7a and 7b of a work table 7 are rotatably mounted on the post member 6a via journal bearings (not shown). . As a result, the workbench 7 is supported by the vertical post 6 so as to be horizontally rotatable. The upper mounting bracket 7a is mounted and mounted on the upper part of the post member 6a of the vertical post 6. At this time, the ring disk-shaped load cell 11 is mounted on the upper part of the post member 6a. An upper mounting bracket 7 a of the workbench is placed on the load cell 11. Therefore, the load of the workbench 7, that is, the weight of the worker who is on the workbench 7, the weight of the tool and the like placed on the workbench 7, is detected by the load cell 11.

A leveling device composed of an upper leveling cylinder 5a and a lower leveling cylinder 5b is attached to the work vehicle for aerial work, and the workbench 7 is always held horizontally regardless of the ups and downs of the boom 3. . Further, jacks 9 that extend and support the vehicle body 1 at the time of work are attached to the vehicle body 1 at four positions in front, rear, left and right.

In the aerial work vehicle configured as described above, a work range restricting device that restricts the operation of the telescopic boom 3 is provided so that the overturning moment acting on the vehicle body does not exceed a predetermined value. There is. This device detects the hoisting angle and the amount of expansion and contraction of the telescopic boom 3 and calculates the actual posture position of the telescopic boom 3. Further, the load of the work table 7 provided at the tip of the boom 3 is measured by the load cell 11 placed on the upper part of the post member 6 a of the vertical post 6. Then, the actual moment Mr is calculated based on the measured load and the actual posture position of the boom 3.

On the other hand, the work range regulating device is also provided with a permissible moment calculator that calculates a permissible moment Ma by receiving a detection signal such as a turning angle of the swivel base 2 and compares the actual moment Mr with the permissible moment Ma. To do. Then, when the actual moment Mr exceeds the allowable moment Ma, a regulation signal is output to the boom operation control means to regulate the operation of the telescopic boom 3 to ensure work safety.

Here, in order to secure the safety of the above work, it is necessary to accurately measure the load of the workbench 7. That is, as shown in FIG. 1, the post member 6a on which the load cell 11 is mounted is sandwiched by mounting brackets 7a and 7b which are fixed and extend horizontally from the upper and lower sides of the workbench 7. Here, one end of each of the mounting brackets 7a and 7b is fixed to the workbench 7, and the other end is a plate member that extends vertically and is provided with an insertion hole for the support pin 8. Therefore, for example, it is assumed that the dimension from the lower surface of the upper mounting bracket 7a to the upper surface of the lower mounting bracket 7b is the same as the combined dimension of the thickness Lt of the load cell 11 and the vertical thickness dimension Pt of the post member 6a. . At this time, when the mounting bracket 7b is fixed to the workbench 7 and the lower mounting bracket 7b is fixed in a state of being warped upward, the lower mounting bracket 7b and the post member 6a interfere with each other, and the load cell Since a force acts in the direction of pushing up 11, the accurate load on the workbench 7 cannot be measured. Even when the mounting brackets 7a and 7b are fixed without warping, the mounting brackets 7a and 7b have only one end fixed to the workbench 7, so that when the workbench 7 is rotated. In some cases, the mounting brackets 7a and 7b are twisted, and a force other than the load of the workbench 7 is applied to the load cell 11.

Therefore, the workbench 7 and the post member 6a are attached by the workbench mounting structure according to the present invention. The upper mounting bracket 7a is provided with an insertion hole 7c into which the support pin 8 can be inserted, and a similar insertion hole 11a is also provided at the center of the load cell 11. The post member 6a is also provided with an insertion hole 6b into which the support pin 8 can be inserted, and the load cell 11 is disposed while being sandwiched between the lower surface of the upper mounting bracket 7a and the upper portion of the post member 6a. The support pin 8 is inserted into 6b, 7c and 11a.

A seat surface 8b having a flat end surface is formed in the lower portion of the support pin 8, and a screw portion 8c is formed so as to project from the seat surface 8b. The length L2 from the lower surface of the flange portion 8a to the seat surface 8b is smaller than the total dimension L1 of the thickness Bt of the upper mounting bracket 7a, the thickness Lt of the load cell 11 and the vertical thickness dimension Pt of the post member 6a. It is set to be long by L 3. The gap L3 has such a dimension that the lower mounting bracket 7b and the lower surface of the post member 6a do not interfere with each other even if the mounting brackets 7a and 7b are warped, so that the load cell 11 due to the warp of the brackets is caused. It is possible to prevent the occurrence of an error in the detection load of.

Further, a flange portion 8a that abuts on the upper surface of the upper support bracket 7a is provided on the upper portion of the support pin 8, and is screwed to the upper support bracket 7a by a mounting bolt 12. The screw portion 8c formed so as to project from the seat surface 8b penetrates the fixing hole 7d provided in the lower mounting bracket 7b and is screwed by the nut 13. As a result, the rigidity of the mounting brackets 7a and 7b can be increased without increasing the plate thickness of the mounting brackets 7a and 7b. Twist can be prevented. As a result, the load cell 11 sandwiched between the upper portion of the vertical post 6a and the lower surface of the upper mounting bracket 7a is not twisted, so that the accurate load on the workbench 7 can be measured. The accuracy of work range regulation can be improved.

In the above embodiment, when the support pin is arranged between the upper and lower brackets, the screw portion protruding from the lower surface of the lower bracket is screwed by the nut. However, the present invention is not limited to this, and a female screw may be formed on the seat surface without protruding the male screw from the seat surface, and the lower surface of the lower bracket may be screwed with a bolt.

[0018]

[Effect of device]

 As described above, the workbench mounting structure for an aerial work vehicle according to the present invention includes a vertical pin post member on a support pin fixed between a pair of upper and lower mounting brackets fixed to the workbench. Is rotatably disposed, and a load detector is sandwiched and disposed between the post member and the upper bracket. The distance from the lower surface of the upper bracket to the bearing surface of the support pin that contacts the upper surface of the lower bracket is greater than the combined vertical thickness of the post member and the vertical thickness of the load detector. It is dimensioned. As a result, the bracket will not be twisted due to the turning operation of the workbench, and even if each bracket is warped, it will not interfere with the load cell, so the load on the workbench can be accurately detected. .

[Brief description of drawings]

FIG. 1 is a side view showing a workbench mounting structure for an aerial work vehicle according to the present invention.

FIG. 2 is a side view of an aerial work vehicle equipped with this workbench mounting structure.

[Explanation of symbols]

 2 swivel base 3 telescopic boom 6 vertical post 6a post member 7 workbench 8 support pin 11 load cell

Claims (1)

[Scope of utility model registration request] 1. A boom in which operations such as expansion and contraction and ups and downs are freely arranged on a vehicle body, a vertical post attached to the tip of the boom, and a horizontal swing is freely attached to the vertical post. A workbench mounting structure for an aerial work vehicle having a workbench, comprising a pair of upper and lower mounting brackets horizontally extending and fixed from the workbench, and vertically extending and fixed between the upper and lower mounting brackets. Support pin, a post member of the vertical post that is rotatably disposed between the upper and lower mounting brackets by inserting the support pin, and is sandwiched between the post member and the upper mounting bracket. The load detector is provided, the support pin has a seat surface that abuts the upper surface of the lower mounting bracket, the distance from the lower surface of the upper mounting bracket to the seat surface of the support pin, Workbench mounting structure of aerial platforms, characterized in that the serial is larger than the dimension in conjunction vertical thickness dimension and a vertical thickness dimension of the load detector of the post member.