JP2003104700A - Vehicle for high lift work - Google Patents

Abstract

PROBLEM TO BE SOLVED: To perform overturning preventive control by detecting the attitude and contracted state of a post. SOLUTION: A turning, derricking and telescopic boom 4 is disposed on a vehicle, and the vertically extensible post 12 supported to a supporting arm 6 is disposed at the tip of the boom 4. A workbench 18 is disposed at the tip of the post 12, and the post 12 is provided with a post derricking motion sensor 13 to detect the angle of the post 12. A post extension sensor 14 is provided at the lower part of a telescopic cylinder 11d of the post 12 to detect the contracted state of the telescopic cylinder 11. A control device 50 allows the telescopic cylinders 11a-11d to be extensible when the post 12 detected by the post derricking motion sensor 13 is positioned at a prescribed angle including a vertical line to the ground surface. The control device 50 allows the derricking motion of the supporting arm 6 when the post 12 detected by the post extension sensor 14 is contracted to a prescribed length or less including the totally contracted state. This constitution can positively prevent the abrupt change of overturning moment caused by the change of a center-of-gravity position, and overturning of the vehicle for high lift work can be prevented.

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an aerial work vehicle,
Particularly, the present invention relates to an aerial work vehicle suitable for maintenance and inspection of bridges and the like. 2. Description of the Related Art An aerial work vehicle rotates, raises and lowers, and expands and contracts a boom mounted on a vehicle body, and moves a work table mounted at the end of the boom to move the work table to a required place. Deploy. Also, in the maintenance and inspection work on the back side of the bridge floor, a technique of arranging a work table on the back side of the bridge floor by combining a plurality of booms capable of turning, raising and lowering, and extending and retracting from an aerial work vehicle installed on the bridge is disclosed in Japanese Patent Application Laid-Open No. H08-08380. No. 295495. In these conventional aerial work vehicles, since the overturning moment acts on the vehicle body due to the change in the position of the center of gravity accompanying the movement of the work table and the boom, a plurality of jacks are provided on the side of the vehicle body as measures to prevent the vehicle from overturning, and during work, These jacks are installed to stably support the vehicle body. The operation by the conventional aerial work vehicle will be briefly described with reference to FIG.
A worker gets into the workbench 18 of the aerial work vehicle 1 arriving at the work site in the workbench storage posture, and moves the workbench 18 to a desired position by operating an operation device (not shown) provided on the workbench 18. Let it. [0003] In the above-mentioned conventional aerial work vehicle, the post 1 does not maintain the vertical
2 or when the support arm 6 is raised and lowered (arrow A) with the post 12 extended, the center of gravity changes from the position B to the position C, and the overturning moment increases sharply. In particular, when the post 12 has an extended length that is longer than the jack width L1 between the jacks 20 provided on the side of the vehicle body, even if the vehicle body 1 is held by the jack 20, it corresponds to the change of the overturning moment. No, there is a risk that the aerial work vehicle will fall over as a result. The present invention has been made in view of such circumstances, and an object of the present invention is to provide an aerial work vehicle capable of preventing a sudden overturning moment from occurring and preventing a vehicle body from overturning. I do. [0005] In order to achieve the above object, according to the present invention, a vehicle body having wheels at a lower portion and capable of traveling, and a swivel rotatably provided on the vehicle body, are provided. Table and
A boom that is undulated and extendable at the top of the swivel,
An angle detecting means for detecting the posture of the post, in a high-altitude work vehicle equipped with a post provided at the tip end of the boom so as to be undulated and extendable, and a worktable provided at the tip end of the post, Position detecting means for detecting the contracted state of the post, and when the angle detecting means detects that the post is located in a predetermined angle range including a vertical line with respect to the ground, the post can expand and contract operation, and, Control means for enabling the post to undulate when the position detection means detects that the post has contracted to a predetermined length or less. According to the present invention, the post can be extended and retracted when the post is positioned within a predetermined angle range including the vertical line, and the post can be raised and lowered when the post contracts to a predetermined length or less. Therefore, it is possible to prevent the occurrence of the overturning moment due to the change in the position of the center of gravity, and thus the overturning vehicle can be prevented from overturning. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an exploded perspective view of an aerial work vehicle according to the present invention. 1 and 2 show an aerial work vehicle according to the present invention. The aerial work vehicle has wheels 2 at the lower part of the body 1,
A turntable 3 that is turned by a turn motor (not shown) is disposed on the vehicle body 1, and a boom 4 is mounted on the turntable 3.
Are supported so as to be able to undulate. That is, in FIG. 2, the boom 4 is rotatably provided on the swivel base 3 with the shaft 3 a as a fulcrum, and is raised / lowered by a lifting / lowering cylinder 5 provided alongside the boom 4. The boom 4 includes a base boom 4a and a distal boom 4b that are pivotally supported by the swivel 3.
a, the tip boom 4b is nested into the boom 4b.
The end boom 4 is provided by a cylinder (not shown)
Expand and contract b. A support arm 6 is rotatably supported at the tip of the tip boom 4b via a shaft 7 provided at the tip of the tip boom 4b. A control arm 8 formed in an inverted shape is rotatably supported on the shaft 7 at a bent portion 8a. Further, the upper end of the control arm 8 is provided with a post undulating cylinder 9 provided at the tip of the tip boom 4b.
It is connected to. Further, one end of a regulating cylinder 10 is rotatably supported at the lower end of the control arm 8, and the other end of the regulating cylinder 10 is pivotally supported at the lower end of the support arm 6. As a result, when the post undulating cylinder 9 is operated,
Support arm 6 via control arm 8 and regulating cylinder 10
Undulate. In FIG. 2, a post 12 is fixed to the tip of the support arm 6. The post 12 is attached to the tip of the support arm 6 so as to be vertical when the regulating cylinder 10 is fully contracted. The nesting cylinders 11a to 11d are inserted into the post 12, and the nesting cylinders 11a to 11d can be extended and contracted by a post telescopic cylinder (not shown) provided inside the post 12. The post 12 is provided with a post undulation sensor 13 as shown in FIG. 3, and detects the angle of the post 12. The post undulation sensor 13 may be any sensor that can detect a change in posture from an initial angle, and examples include an angular velocity sensor using a gyro or the like. As shown in FIG. 4, a post expansion / contraction sensor 14 is provided below the telescopic cylinder 11d of the post 12. Further, a projecting member 14a for operating the post expansion / contraction sensor is provided at the lower part of the telescopic cylinder 11a so as to protrude.
The distal end of “a” is arranged so as to contact the post expansion / contraction sensor 14 to operate the post expansion / contraction sensor 14. In addition to the limit switch as the post expansion / contraction sensor 14, a contact switch sensor such as a micro switch that changes a contact point when a force is applied by the action of a spring, a beard sensor, and an interruption type photo using light interruption. A sensor or a non-contact type sensor such as a reflection type photo sensor that detects the presence or absence of reflected light may be used. Further, a wire reel type variable resistor (potentiometer) may be used as the post expansion / contraction sensor 14. In this case, a variable resistor is provided on the wire reel type winding shaft, and the wire end unwound from the wire reel is fixed to the tip of the protruding member 14a, so that the telescopic length of the telescopic cylinders 11a to 11d is increased. Can be detected from the resistance value of the variable resistor. In FIG. 2, a bracket 15 and a bracket swinging cylinder 17 for swinging a revolving race 16 provided below the bracket 15 are provided at the tip of the telescopic cylinder 11d. The bracket oscillating cylinder 17 includes the undulating cylinder 5 and the post undulating cylinder 9.
Are connected to a closed circuit through an oil passage (not shown), and the bracket swing cylinder 17 is expanded and contracted in accordance with the expansion and contraction of these cylinders to swing the turning race 16 up and down.
8 can be kept horizontal. A worktable 18 is provided below the swing race 16 so as to be capable of horizontal swing (swinging operation). The worktable 18 horizontally turns by driving a turning race 16 by a built-in horizontal turning motor (not shown). The work table 18 has a floor surface 18a and the floor surface 1a.
8a Railing 18 standing upright from the edge
b. Further, the floor surface 18a is a floor surface 18a.
And the floor 1 slidably provided inside the floor 18a
8c, the worktable 18 can be extended and contracted in the longitudinal direction, and the work space of the worker can be adjusted. Further, an operation device 19 for operating the operator to move the operation table 18 is provided above the operation table 18. An operator who has boarded the worktable 18 operates an operation lever or the like of the operation device 19 to rotate the swivel 3, raise and lower the boom 4, raise and lower the holding arm 6, expand and contract the post 12, and move the worktable 18. The work table can be moved to a desired height by performing the above-mentioned operations and the like, and work at a height can be performed. A similar operation device 19a is provided also on the upper part of the vehicle body, and the same operation as described above can be performed. As shown in FIG. 2, jacks 20 including a beam 21, a beam post 22, and a roller 23 are provided at four positions on the front, rear, left and right of the vehicle body 1. The jack 20 allows an operator to operate a jack operating device 65 provided at the rear portion of the vehicle body 1 so that the beam 21 can be expanded and contracted in the vehicle width direction and the beam post 22 can be expanded and contracted. In addition, a roller 23 rotatable in the traveling direction of the vehicle body 1 is provided at a lower portion thereof. At the time of operation, the vehicle body 1 is extended by extending the beam post 22 of the beam 21 to project the beam 21 outward in the width direction as shown in FIG. 2, and extending the beam post 22 downward to contact the roller 23 with the ground. Stable support. Next, a control block diagram of the aerial work vehicle will be described with reference to FIG. The control device 50 includes operating devices 19, 19
a, a post undulation actuator 52 that receives a signal from the post undulation sensor 13 and the post expansion / contraction sensor 14 and operates the post undulation cylinder 9;
A control signal is transmitted to each of the alarm devices 54. More specifically, a detection signal relating to the angle of the post 12 detected by the post undulation sensor 13 is transmitted to the regulating unit 51 in the control device 50. Further, the post 12 detected by the post
The detection signal of the expansion / contraction state of the
Sent to When the post 12 is not located within a predetermined angle range including a vertical line with respect to the ground, the post undulation sensor 1
3 transmits a regulation signal to the regulation unit 51, and the regulation unit 51 regulates the operation of the post undulation actuator 52. Also, the telescopic cylinders 11a to 11 of the post 12
If d is not the total contraction, a regulation signal is sent from the post extension / contraction sensor 14 to the regulation section 51, and the regulation section 51 regulates the operation of the post extension / contraction actuator 53. When a wire-reel-type variable resistor is used as the post expansion / contraction sensor 14, a restriction signal is sent from the post expansion / contraction sensor 14 to the restriction unit 51 when it is not detected that the post has contracted to a predetermined length or less. Alternatively, the operation of the post expansion / contraction actuator 53 may be restricted by the restriction unit 51. The overturning / allowable moment calculation comparing section 55
In the above, the overturning moment and the permissible moment acting on the vehicle body 1 are set, and the calculated overturning moment information is compared with the permissible moment information. Output to regulate the operation of various actuators. The operation of the aerial work vehicle constructed as described above will be described with reference to FIGS. With the booms stored in the vehicle body 1, the vehicle body 1 is first supported by the jack 20. Beam 21 by jack operating device 65
, The beam post 22 is extended to the desired position in the vehicle width direction, and then the beam post 22 is extended downward to ground the roller 23. In this state, since the wheels 2 are in contact with the ground, driving the rear wheels 2 enables the vehicle body to run stably. The movement of the worktable 18 to a desired height will be described. The boom 4 above the swivel 3 is raised and lowered by the raising and lowering cylinder 5. Next, as shown in FIG.
b, the post cylinder 12 and the worktable 18 provided on the tip boom 4b are raised. Next, as shown in FIG. 6, the swivel base 3 is swiveled in the horizontal direction, and the boom 4 is directed in a desired working direction. Further, the turning race 16 provided on the work table 18 is driven to horizontally turn the work table 18 until the work table 18 is substantially perpendicular to the boom 4. Next, the post 12 is raised and lowered. As shown in FIG. 7, the support cylinder 6 is rotated about the shaft 7 by fully contracting the regulating cylinder 10. Thereby, the post 12 fixed to the support arm 6 is raised and lowered in the vertical direction.
At this time, the swing race 16 is swung up and down by the bracket swinging cylinder 17 connected to the regulating circuit 10 and a closed circuit through an oil passage (not shown), and the worktable 18 is kept horizontal. The angle of the post 12 is detected by a post undulation sensor 13 provided on the post 12, and the detected value is input into the control device 50 of the vehicle body 1. Regulator 5 of control device 50
Until the post 12 is positioned within a predetermined angle range including the vertical line due to the regulation control in 1, the driving of the nested cylinders 11a to 11d in the post 12 described later cannot be performed. At this time, when the nested cylinders 11a to 11d are driven, an alarm operation by the alarm device 54 is performed from the control device 50. After the post 12 is positioned within a predetermined angle range including the vertical line, a post telescopic cylinder (not shown) provided inside the post 12 is extended to extend the telescopic cylinder 11a.
To 11d are sequentially extended in the vertical direction. Accordingly, the workbench 18 descends along the bridge wall 40. After lowering the worktable 18 to a position where work on the back surface of the bridge 41 can be performed, the worktable 18 is horizontally turned to a desired work position by the turning race 16. The floor surface 18c is replaced with the floor surface 18a.
It is possible to adjust the working space by extending from. From the above, the work on the back surface of the bridge 41 can be performed. At the time of the above operation, the operation of the control device 50 such that the overturning moment exceeds the allowable moment is restricted, and if the post 12 is not vertical, the nesting cylinders 11a to 11d in the post 12 can be driven. If the operation is not possible and the operation is performed in contrast thereto, an alarm operation is performed by the alarm device 54. By performing the above-described regulation, it is possible to prevent a sudden change in the overturning moment, and therefore, it is possible to reliably prevent the overturning vehicle from overturning. Next, the collecting operation of the work table 18 will be described. The floor 18c is housed in the floor 18a, and the workbench 18 is horizontally rotated by the revolving race 16 until it is substantially perpendicular to the boom 4. Next, the telescopic cylinders 11a to 11d are sequentially contracted in the vertical direction. At this time, as shown in FIG. 7, the post-extension sensor 14 provided below the telescopic cylinder 11d is operated by the post-extension sensor operating projection member 14a provided below the telescopic cylinder 11a. 11a to 11d are completely contracted. If the post expansion / contraction sensor 14 does not operate, the support arm 6 described below cannot be raised / lowered by the regulation control in the regulation unit 51 inside the control device 50.
When the operator performs the up / down operation of the support arm 6 without fully contracting the telescopic cylinders 11a to 11d, the control device 5
From 0, an alarm operation by the alarm device 54 is performed. When a wire reel type variable resistor is used as the post expansion / contraction sensor 14, if the operator performs the up / down operation of the support arm 6 when it is not detected that the post has contracted to a predetermined length or less. Then, an alarm operation by the alarm device 54 is performed. After fully retracting the telescopic cylinders 11a to 11d, the support arm 6 is raised and lowered by the regulating cylinder 10 until the post 12 is horizontal as shown in FIG. Next, the tip boom 4b is contracted to lower the post 12 and the work table 18 provided on the tip boom 4b, and at the same time, the swivel 3 is turned horizontally to turn the boom 4 toward the front of the vehicle body 1. Finally, the up-and-down cylinder 5 is contracted, and the boom 4 is stored in the vehicle body 1. At the time of the collecting operation of the work table 18, the control device 50 restricts the operation such that the overturning moment exceeds the allowable moment. In particular, if the nesting cylinders 11a to 11d are not fully contracted, the up-and-down operation of the support arm 6 is not performed. Be regulated. Therefore, it is possible to reliably prevent a sudden change in the overturning moment due to a change in the position of the center of gravity, and it is possible to reliably prevent the overturning vehicle from overturning. The above-described aerial work vehicle of the present invention is not limited to the above-described embodiment, and the post up / down sensor 13 is provided on the post 12.
A sensor for detecting the angle of the post 12 may be provided, and the positions of the up-and-down cylinder 5 and the post-up and down cylinder 9 may be detected, and the angle of the post 12 may be obtained by calculating from the value detected by the sensor and the position detection value. A goniometer 30 is separately provided on the side surface of the post 12 near the worktable 18, and the post 1 is visually recognized by an operator.
The angle of 2 may be determined. Further, a display means for displaying the angle detected by the support arm 6 and the post undulation sensor 13 provided near the post 12 may be provided in the operating devices 19 and 19a. Further, the operating devices 19 and 19a are provided with lamps indicating that the post can be moved, and are turned on only when the angle detected by the post undulation sensor 13 is vertical, thereby informing the operator whether the post 12 can be extended or retracted. You may do it. As described above, according to the aerial work vehicle of the present invention, by providing the angle detecting means and the position detecting means for detecting the posture and the expansion / contraction state of the post, the posture and the position of the post can be improved. The state of expansion and contraction can be reliably grasped. This enables the post to expand and contract when the post is positioned within a predetermined angle range including the vertical line, and allows the post to retract when the post shrinks to a predetermined length or less. Abrupt changes can be reliably prevented, and the work vehicle at a height can be prevented from tipping over.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a side view showing an aerial work vehicle according to the present invention. FIG. 2 is a rear view showing an aerial work vehicle according to the present invention. FIG. 3 is an aerial work according to the present invention. FIG. 4 is a perspective view showing details of a post up-and-down sensor part of the vehicle. FIG. 4 is a perspective view showing details of a post extension sensor part of the aerial work vehicle according to the present invention. FIG. 6 is a plan view showing a part of the work process of the aerial work vehicle according to the present invention. FIG. 7 is a rear view showing a part of the work process of the aerial work vehicle according to the present invention. FIG. 8 is a control block diagram showing a configuration example of a control device for an aerial work vehicle according to the present invention. FIG. 9 is a rear view showing a conventional aerial work vehicle. 3, swivel, 4 boom, 6 support arm, 8 control arm, 11 nested cylinder,
12 ... post, 13 ... post undulation sensor, 14 ... post expansion / contraction sensor, 18 ... work table, 19, 19a ... operating device,
20: jack, 50: control device

   ────────────────────────────────────────────────── ─── Continuation of front page    (72) Inventor Takaaki Oba             Saitama prefecture Ageo city large section Ryoke character Yamashita 1152 address 10               Aichi Corporation Ageo Corporation             Inside the hall (72) Inventor Asahi Tanaka             Saitama prefecture Ageo city large section Ryoke character Yamashita 1152 address 10               Aichi Corporation Ageo Corporation             Inside the hall (72) Inventor Jun Kubo             Saitama prefecture Ageo city large section Ryoke character Yamashita 1152 address 10               Aichi Corporation Ageo Corporation             Inside the hall (72) Inventor Takashi Sasaki             Saitama prefecture Ageo city large section Ryoke character Yamashita 1152 address 10               Aichi Corporation Ageo Corporation             Inside the hall F term (reference) 3F333 AA11 AB14 AC02 BA04 BA12                       BB03 BB09 BB23 BB26 BD02                       BE02 CA24 FA09 FA11 FA34                       FA36 FD03 FD08 FD09 FE04                       FE05 FE09

Claims (1)

Claims: 1. A vehicle body capable of traveling with wheels at a lower portion thereof, a swivel provided on the vehicle body so as to be freely rotatable, and an up-and-down, telescopically provided at an upper portion of the swivel. An aerial work vehicle comprising a boom, a post provided at the tip of the boom so as to be undulated and extendable, and a worktable provided at the tip of the post. An angle detection for detecting a posture of the post. Means, position detecting means for detecting a contracted state of the post, and when the angle detecting means detects that the post is located within a predetermined angle range including a vertical line with respect to the ground, the post can be expanded and contracted. And a control means for enabling the post to be raised and lowered when the position detection means detects that the post has contracted to a predetermined length or less.