JP7213666B2 - Safety device for aerial work platform - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a safety device for an aerial work vehicle equipped with a jack with rollers for stably supporting a vehicle body during work.

The aerial work vehicle comprises a boom arranged to move up and down freely on a vehicle body that can travel, and a workbench provided at the tip of the boom for a worker to ride on. is a vehicle in which the workbench can be moved to an arbitrary height position by operating an operating device provided on the workbench to operate the boom, and is used for work at various heights. there is By the way, when inspecting and repairing overhead lines along the road, or inspecting and repairing the front and back surfaces of the ceiling in tunnels or bridges, etc., in order to improve work efficiency, it is necessary to attach the boom to the vehicle body. It is configured to be able to travel even when the boom is operated (while the workbench is held at a high position) without being temporarily stored on top. Therefore, in such an aerial work vehicle, a plurality of jacks each having an outrigger (outrigger beam) that can extend to the side of the vehicle body and a jack that is disposed at the tip of the outrigger and can extend and contract downward. Equipped with a roller jack (jacking device), a rotatable roller is provided at the lower end of the jack that supports the vehicle body, and the roller is grounded with the outriggers projecting to the side of the vehicle body to support the vehicle body with the jack. , and a work vehicle that can travel by driving wheels in a supported state of the vehicle body is known (see, for example, Patent Document 1).

JP-A-2005-126019

In the above aerial work platform, the larger the outrigger extension, the more stable the vehicle during work. Quantities may be limited. Here, in a state where the aerial work vehicle is working with the outrigger extension amount less than a predetermined amount (retracted state), the tip of the boom on the rear side of the vehicle body is moved out of the allowable work range (allowable work radius). When performing aerial work by raising it to a predetermined height or more in the vicinity of the extension (especially because the allowable work range is set wider on the rear side than on the front side of the vehicle body), for example, the road surface If there is an inclination, etc., not only will the overturning moment act according to the movement position of the workbench, but also the moment will be increased by the slope of the road surface, so the vehicle body during work will be tilted to the left and right sides (storage). There is a risk that it will tilt to the outrigger side of the state, and there is a problem that the safety of work is lowered.

SUMMARY OF THE INVENTION The present invention has been made in view of such problems, and aims to improve the safety of work by stably supporting a car body during work regardless of the amount of protrusion of a roller jack device toward the side of the car body. To provide a safety device for an aerial work vehicle capable of

In order to solve the above-mentioned problems, the safety device for a vehicle for work at height according to the present invention comprises a vehicle body having wheels and capable of traveling; an operating device for operating the vehicle; and a plurality of roller jack devices comprising outrigger beams that can extend to the side of the vehicle body and jacks that are provided at the ends of the outrigger beams and extend and retract under the vehicle body. A roller rotatable in the running direction of the vehicle body is disposed at the lower end of each of the jacks, and the vehicle body is supported by the plurality of roller jack devices by grounding the rollers while grounding the wheels. In a safety device for a vehicle for work in high places, wherein the vehicle body is configured to be able to travel under normal conditions, position detecting means for detecting the position of the tip portion of the boom and the amount of protrusion of the outrigger beam to the side of the vehicle body are detected. and setting a front side work range and a rear side work range in front and rear of the vehicle body as an allowable work range in which movement of the tip portion of the boom outside the vehicle body is permitted, and working range setting means for setting a left working range and a right working range on the left side and right side of the vehicle body; and operation control means for controlling the operation of the boom based on an operation signal from the operating device. In the work range, a predetermined reference height is set as a limit value of the height to which the tip of the boom can be moved. When the amount of extension of the beam is less than a predetermined amount, the limit value of the height at which the tip of the boom can be moved within the working range on the rear side is restricted to a regulation height set lower than the reference height. and the operation control means controls the boom tip portion to reach the restricted height within the rear working range when the extension amount of any one of the outrigger beams of the plurality of roller jack devices is less than a predetermined amount. It is characterized by restricting the operation of the boom that moves upward beyond.

In the above-described safety device for a vehicle for work at height, the working range setting means sets a first intermediate working range between the left working range and the rear working range, and sets the first intermediate working range between the left working range and the rear working range. A second intermediate work range is set between the rear side work range, and the work range setting means is configured so that the outrigger beam of the left roller jack device out of the plurality of roller jack devices has an extension amount less than a predetermined amount. In some cases, the height at which the tip portion of the boom can be moved across the rear working range and the first intermediate working range is restricted to the restricted height, and the right side of the plurality of roller jack devices is controlled. When the extension amount of the outrigger beam of the roller jack device is less than a predetermined amount, the height at which the tip of the boom can be moved across the rear working range and the second intermediate working range is defined as the restricted height. is preferably limited to

According to the safety device for the aerial work vehicle according to the present invention, when the amount of protrusion of any one of the plurality of roller jack devices is less than a predetermined amount while the vehicle is traveling, the safety device is set around the vehicle body. Without reducing the entire allowable working range (without reducing both the working radius and lift at the same time), within the allowable working range, the boom in the front working range and side working range (left working range, right working range) While maintaining the limit value of the height at which the tip of the boom can be moved to the reference height, in the rear working range, by limiting the limit value of the height at which the tip of the boom can be moved to the regulation height, Since the entire allowable working range is not subject to height restrictions, and a wide working radius equivalent to that before height restrictions can be secured, it is easy to use for workers and can be used regardless of the road surface inclination. It is possible to stably support the vehicle body and improve work safety.

In addition, in the safety device for the aerial work vehicle according to the present invention, when the amount of protrusion of the left roller jack device among the plurality of roller jack devices is less than a predetermined amount while the vehicle is traveling, the rear working range and the limit value of the height at which the tip of the boom can be moved across the first intermediate work range is restricted to the regulated height, and if the amount of extension of the right roller jack device is less than a predetermined amount, the rear By limiting the limit value of the height at which the tip of the boom can be moved across the side work range and the second intermediate work range to the regulation height, the amount of overhang is less than the predetermined amount. Accordingly, the work range that limits the height of the lift is expanded, and the vehicle body can be stably supported regardless of the amount of protrusion of the roller jack device, so that work safety can be further improved. .

1 is a side view of an aerial work vehicle equipped with a safety device according to an embodiment; FIG. Fig. 2 is a rear view of the aerial work vehicle; FIG. 3 is a block diagram showing a control configuration in the aerial work vehicle; FIG. 4 is a schematic diagram showing an example of an allowable work range in a plan view that is set corresponding to a boom hoisting posture and an extension amount of an outrigger in the aerial work vehicle. FIG. 4 is a schematic diagram showing an example of an allowable work range in a side view that is set corresponding to a turning posture of a boom and an extension amount of an outrigger in the aerial work platform. FIG. 4 is a schematic diagram showing the relationship between the amount of extension of the outriggers and the working range in which the lifting height is regulated;

Preferred embodiments of the present invention will be described below with reference to the drawings. A vehicle for high lift work 1 equipped with a safety device according to the present embodiment is shown in FIGS. 1 and 2. First, the overall configuration of the vehicle for high lift work 1 will be described with reference to these figures.

The aerial work vehicle 1 has a driving cab 2a in the front part of the vehicle body 2, and is configured based on a truck-type vehicle capable of traveling by wheels 3 arranged on the front, rear, right, and left sides of the vehicle body 2, respectively.

Roller jacks 10 are provided on the front, back, left and right of the vehicle body 2 for lifting and supporting the vehicle body 2 during high-place work. The roller jack 10 includes an outrigger (outrigger beam) 11 that can extend and contract in the lateral direction (vehicle width direction) of the vehicle body 2, a jack 12 that is provided at the tip of the outrigger 11 and can extend and contract in the vertical direction, and the lower end of the jack 12. A roller 13 is attached to a portion of the jack 12 and is rotatable in the running direction of the vehicle, and a jack base (grounding plate) 14 is attached to the lower end of the jack 12 and is vertically swingable. The outrigger 11 is configured to be able to extend and contract in the left-right direction (vehicle width direction) by an outrigger cylinder 15 (see FIG. 3) provided inside the outrigger 11 . The jack 12 is configured to be vertically extendable by a jack cylinder 16 (see FIG. 3) provided in the jack 12 . The jack base 14 is rotatably supported by the rotation shaft of the roller 13. The jack base 14 is centered on the rotation shaft, and is positioned directly below the roller 13 to cover the lower surface of the roller 13 and to the side of the roller 13. and a retracted position where the lower surface of the roller 13 is exposed. The jack base 14 is held at the grounded position or the retracted position by being locked by a predetermined locking means. Here, in the supporting posture of the vehicle body 2 by the roller jack 10 (the working posture of the aerial work vehicle 1), the jack base 14 is swung downward to the grounding position to ground the jack base (grounding plate) 14, and A stationary work posture in which the vehicle body 2 is supported with the wheels 3 completely lifted, and a state in which the jack base 14 is swung to an upper retracted position to ground the rollers 13 and also the wheels 3 (that is, the wheels 3) and a traveling work posture supported by the travelable posture according to 3). The vehicle body 2 is provided with a jack operation device 18 (see FIG. 3) for operating each roller jack 10 .

A swivel base 5 that is driven by a boom swivel motor 6 and configured to be horizontally swivelable around a vertical axis is provided in the mounting area behind the operating cab 2a of the vehicle body 2 . A base end portion of a boom 20 is attached to the upper portion of the swivel base 5 via a foot pin 7 so as to be vertically swingable (flexible).

The boom 20 has a configuration in which a base end boom 21, an intermediate boom 22 and a tip boom 23 are telescopically combined in order from the swivel base 5 side, and a boom telescopic cylinder 26 provided therein is driven to extend and retract. , the boom 20 can be telescopically moved in the axial direction (longitudinal direction). A boom hoisting cylinder 25 is straddled between the base end boom 21 and the swivel base 5. By extending and retracting the boom hoisting cylinder 25, the entire boom 20 can be moved in the upper and lower planes (vertical plane). It can be raised and lowered.

A workbench bracket 30 is pivotally supported at the tip of the tip boom 23 so as to be vertically swingable, and a workbench 40 is arranged on the workbench bracket 30 . A cylinder bracket 31 is provided at the tip of the tip boom 23 and extends substantially parallel to the tip boom 23 . A leveling cylinder 35 is straddled between the cylinder bracket 31 and the workbench bracket 30 . The leveling cylinder 35 expands and contracts based on information detected by a work table inclination detector (not shown) installed on the work table 40, and swings the work table bracket 30 up and down with respect to the tip boom 23. As a result, the floor surface of the workbench 40 is always kept horizontal regardless of the hoisting angle of the boom 20 . In addition, the workbench bracket 30 is provided with a workbench turning motor 36 (see FIG. 3), and by rotating the workbench turning motor 36, the entire workbench 40 can be horizontally turned. .

The work table 40 includes a substantially rectangular work floor 41 on which an operator can ride, and a handrail 42 provided around the work floor 41 . The workbench 40 is provided with a work operation device 70 having various operation means such as an operation lever, an operation switch, and an operation dial operated by a worker on the workbench 40 . Therefore, a worker on the workbench 40 operates the work operation device 70 to turn the swivel base 5 and the boom 20 (rotating operation of the boom turning motor 6), raise and lower the boom 20 (boom raising and lowering cylinder). 25), telescoping operation of the boom 20 (extension operation of the boom telescoping cylinder 26), turning operation of the work table 40 (rotating operation of the work table turning motor 36), and the like. Although not shown, the vehicle body 2 is also provided with a work operating device (lower operating device) so that a worker on the ground or on the vehicle body 2 can perform the above operation.

As shown in FIG. 3, the operating mechanism of the roller jack 10 and the aerial work equipment (such as the swivel base 5, the boom 20, and the workbench 40 described above) provided on the vehicle body 2 includes a jack operation device 18 and a work operation device 70. A control unit 50 to which an operation signal is input from, an outrigger cylinder 15, a jack cylinder 16, a boom swing motor 6, a boom hoisting cylinder 25, a boom telescopic cylinder 26, and a worktable swing motor 36 (hereinafter collectively referred to as "hydraulic actuator"). and a hydraulic unit 80 that supplies hydraulic oil for operating the

The hydraulic unit 80 includes a hydraulic tank 81 that stores hydraulic oil, a hydraulic pump 82 that is driven by an engine or an electric motor and discharges the hydraulic oil, and a hydraulic actuator that is provided in correspondence with each of the hydraulic pumps 82 and 82. and a control valve 83 for controlling the supply of oil. The control valve 83 includes a first control valve V1 to a sixth control valve V6. Via the third control valve V3 to the boom telescopic cylinder 26, the fourth control valve V4 to the work platform swing motor 36, the fifth control valve V5 to the outrigger cylinder 15, and the jack cylinder 16 Hydraulic oil (pressure oil) discharged by the hydraulic pump 82 is supplied via the sixth control valve V6. The control valve 83 controls hydraulic fluid supplied from the hydraulic pump 82 to each hydraulic actuator in response to a control signal from the control unit 50 (a control signal corresponding to the operation signals from the jack operation device 18 and the work operation device 70). It controls the supply direction and supply amount, and controls the operating direction and operating speed of each hydraulic actuator (controls the operating direction and operating speed of the roller jack device 10 and the aerial work equipment).

The control unit 50 receives detection information (detection signals) from the position detection device 60, the jack extension amount detector 65, the jack base switching detector 66, and the like.

The position detection device 60 includes a boom turning angle detector 61 that detects the turning angle of the boom 20 (swivel base 5) with respect to the vehicle body 2, a boom hoisting angle detector 62 that detects the hoisting angle of the boom 20 with respect to the vehicle body 2, and a boom. boom length detector 63 for detecting the extension amount (length) of boom 20, and work platform turning angle detector 64 for detecting the turning angle of work platform 40 with respect to boom 20 (work platform bracket 30). .

The jack protrusion amount detector 65 detects the protrusion amount of the roller jack 10 (outrigger 11) in the vehicle width direction (that is, the protrusion amount to the left and right sides of the vehicle body 2) in four stages. In the present embodiment, the above-described four levels of extension amount are "minimum extension amount (MIN)", "intermediate extension amount (MID1)", "intermediate extension amount (MID2)", and "maximum extension amount. Amount (MAX)” is set. The minimum amount of extension corresponds to the retracted state of the outriggers 11, and the maximum amount of extension corresponds to the maximum extension of the outriggers 11. FIG. That is, the amount of extension of the outriggers 11 increases by one step in the order of minimum extension amount<intermediate 1 extension amount<intermediate 2 extension amount<maximum extension amount. As the jack extension amount detector 65, instead of the configuration for detecting the extension amount of the outriggers 11 in stages, a configuration for continuously detecting the extension amount of the outriggers 11 may be applied.

The jack base switching detector 66 detects whether the swinging position of the jack base 14 is the grounded position (lower position) or the retracted position (upper position).

The control unit 50 includes a position calculation section 51 , a work posture determination section 52 , a work range setting section 53 and an operation control section 54 .

The position calculation unit 51 calculates the position of the tip of the boom 20 (which may include the workbench 40) with respect to the vehicle body 2 based on the detection information input from the position detection device 60, and obtains the position as a result. The position information of the tip of the boom 20 is output to the operation control unit 54 or the like.

Based on the detection information input from the jack base switching detector 66, the working posture determination unit 52 determines whether the supporting posture of the vehicle body 2 by the roller jacks 10 (the working posture of the aerial work vehicle 1) is the stationary working posture and the traveling working posture. , and the work posture information obtained as a result is output to the work range setting unit 53 or the like.

The work range setting unit 53 stores data of an allowable work range S defined as a region in which the tip of the boom 20 (workbench 40) can be moved without overturning the vehicle body 2. The data of the allowable work range S includes the data of the allowable work range S set when the current work posture is the stationary work posture, and the data of the allowable work range S set when the current work posture is the traveling work posture. data of range S. The allowable work range S set in the travel work posture, which is a feature of this embodiment, will be described below.

The work range setting unit 53 stores data of the allowable work range S corresponding to each of four stages of extension amounts of the roller jack 10 (outrigger 11) as data of the allowable work range S in the traveling work posture. there is As a result, when the current work posture is the traveling work posture, the work range setting unit 53 selects the data of the allowable work range S according to the current extension amount of the outriggers 11 from among the data group of the allowable work range S. read out. Then, the work range setting unit 53 sets the data of the allowable work range S read from the data group of the allowable work range S according to the amount of extension of the outriggers 11 to the current work posture of the vehicle for high lift work 1. It is set as a permissible movable area of the tip portion of the boom 20 depending on the (traveling work attitude) and the extension amount of the outriggers 11 . The outer edge of the allowable work range S (movable area) is an outer edge (operating limit line) that is structurally set according to the relationship between the range that the length of the boom 20 can take and the range that the hoisting angle of the boom 20 can take; Structurally, the tip of the boom 20 can be moved, but from the viewpoint of preventing the overturning moment from becoming excessive, the movement of the tip of the boom 20 must be prohibited. limit line). In the following description, the outer edge of the allowable working range S will be referred to as the "limit line" without distinguishing between the operating limit line and the regulation limit line.

First, the allowable work range S within the swing operation plane (inside the horizontal plane) of the boom 20 will be described. FIG. 4 is a schematic diagram showing an example of a permissible working range S set around the vehicle body 2 corresponding to a certain boom hoisting posture and the amount of extension of the outriggers 11. As shown in FIG. Limit lines L1 to L8 shown in the figure are envelope curves showing the allowable working radius of the boom 20 over all turning positions (360 degrees), and the area surrounded by the limit lines L1 to L8 defines the allowable working range S. showing. In the drawing, the position of the tip of the boom 20 is denoted by P, and the center of rotation of the swivel base 5 is denoted by C. As shown in FIG.

The allowable work range S includes a front work range S1 set in front of the vehicle body 2, a rear work range S2 set in the rear of the vehicle body 2, a left work range S3 set in the left side of the vehicle body 2, A right working range S4 set on the right side of the vehicle body 2, a front left working range S5 set diagonally forward left of the vehicle body 2, a front right working range S6 set diagonally forward right of the vehicle body 2, and the vehicle body. 2, and a rear right working range S8 set diagonally to the right of the vehicle body 2.

The front work range S1 is a region surrounded by an arc-shaped limit line L1 centered on the turning center C. As shown in FIG. The rear working range S2 is a region surrounded by an arc-shaped limit line L5 centered on the turning center C. As shown in FIG. The left working range S3 is a region surrounded by an arc-shaped limit line L7 centered on the turning center C. As shown in FIG. The right working range S4 is a region surrounded by an arc-shaped limit line L3 centered on the turning center C. As shown in FIG. The front left working range S5 is provided between the front working range S1 and the left working range S3, and is an area surrounded by a limit line L8 that continuously connects and interpolates between the limit line L1 and the limit line L7. The front right working range S6 is provided between the front working range S1 and the right working range S4, and is an area surrounded by a limit line L2 that continuously connects and interpolates between the limit line L1 and the limit line L3. The rear left working range S7 is provided between the rear working range S2 and the left working range S3, and is an area surrounded by a limit line L6 that continuously connects and interpolates between the limit lines L5 and L7. . The rear right working range S8 is provided between the rear working range S2 and the right working range S4, and is an area surrounded by a limit line L4 that continuously connects and interpolates between the limit line L3 and the limit line L5. . In the following description, the left work range S3 and the right work range S4 are also collectively referred to as the "side work range".

Next, the allowable work range S on the hoisting operation plane (inside the vertical plane) of the boom 20 will be described. FIG. 5 is a schematic diagram showing an example of a permissible work range S set on the side of the vehicle body 2 corresponding to a certain turning attitude of the boom 20 and the extension amount of the outriggers 11. As shown in FIG. The area surrounded by limit lines L11 to L17 shown in the drawing corresponds to the allowable work range S. FIG. In the drawing, the position of the tip of the boom 20 is denoted by P, and the center of rotation of the swivel base 5 is denoted by C. As shown in FIG. Further, the working radius shown in the drawing means the horizontal distance from an imaginary vertical line passing through the turning center C to the tip of the boom 20 .

In this allowable work range S, the limit line L17 defines the limit value of the height (lift limit value) to which the tip of the boom 20 can be moved among the outer edges of the allowable work range S. Also referred to as a "lift limit line L17". In the present embodiment, the height of the tip of the boom 20 from the ground is also referred to as "the lift of the tip of the boom (ground lift)".

Here, in the present embodiment, of the allowable work range S, the front work range S1, the left work range S3, the right work range S4, the front left work range S5, and the front right work range S6 are determined by the extension amount of the outriggers 11. Regardless, the height of the lift limit line L17 (lift limit value) is set to the reference height Ha set as the maximum lift (mechanical end) of the machine (structurally). In this embodiment, when the maximum lift is 12 m, the reference height Ha is set in the front working range S1, the left working range S3, the right working range S4, the front left working range S5, and the front right working range S6. teeth,
The lift limit is always 12m.

On the other hand, in the allowable work range S, the rear work range S2, the rear left work range S7, and the rear right work range S8 are adjusted according to the amount of extension of the outriggers. ) can be switched. That is, in the rear working range S2, the rear left working range S7, and the rear right working range S8, the extension amount of the outriggers 11 is any of the intermediate 1 extension amount, the intermediate 2 extension amount 2, and the maximum extension amount. In some cases (other than the minimum extension amount), the height of the lift limit line L17 becomes the reference height Ha. The height of the lift limit line L17 is limited to the regulated height Hb within a predetermined work range according to the arrangement (left and right positions) of . In this embodiment, the restricted height Hb is set to, for example, "9 m". Therefore, in the rear working range S2, the rear left working range S7, and the rear right working range S8, depending on the amount of extension of the outriggers 11, the limit value of the lifting height may become a height regulating surface of "12 m". , there are cases where the limit value of the lifting height becomes a height restriction surface of "9m".

Here, FIG. 6 is a schematic diagram showing the relationship between the extension amount of the roller jack 10 (outrigger 11) and the range within the allowable working range S in which the restricted height Hb is set as the limit value of the lifting height.

First, as shown in FIG. 6A, when all the four outriggers 11 have the minimum extension amount, the rear working range S2, the rear left working range S7, and the rear right working range S8. , the height of the lift limit line L17 is restricted to the restricted height Hb.

Next, as shown in FIG. 6B, of the four outriggers 11, the left outrigger 11 (the left front and left rear outriggers 11) has the maximum extension amount, and the right outrigger 11 has the maximum extension amount. 11 (right front and right rear outriggers 11) is the minimum extension amount, the height of the lift limit line L17 is the regulation height across the rear allowable range S2 and the rear right allowable range S8. is limited to Hb. Note that even if only one of the right outriggers 11 (right front and right rear outriggers 11) has the minimum amount of extension, the rear allowable range S2 and the rear right allowable range S8 are not extended. Therefore, the height of the lift limit line L17 is restricted to the restricted height Hb.

Next, as shown in FIG. 6C, among the four outriggers 11, the left outrigger 11 (the left front and left rear outriggers 11) has the minimum extension amount, and the right outrigger 11 has the minimum extension amount. 11 (right front and right rear outriggers 11) is the maximum extension amount, the height of the lift limit line L17 is the regulation height across the rear allowable range S2 and the rear left allowable range S7. is limited to Hb. Note that even when only one of the left outriggers 11 (the left front and left rear outriggers 11) has the minimum extension amount, the rear side permissible range S2 and the rear left side permissible range S7 are straddled. Therefore, the height of the lift limit line L17 is restricted to the restricted height Hb.

In this way, for the rear side of the vehicle body, where the working radius (working range) is set relatively wider than the front side of the vehicle body, by limiting the height of the lift while maintaining the working radius, the rear side of the vehicle body Work at height can be performed by fully using the wide working radius without hindering it.

When the work operation device 70 is operated by a worker on the workbench 40, the operation control unit 54 electromagnetically drives the control valve 83 in response to the operation command signal, and controls the boom swing motor 6 and the boom hoisting cylinder 25. , the boom telescopic cylinder 26, and the workbench swing motor 36 are controlled to supply hydraulic oil from the hydraulic pump 82, thereby controlling the operation of the boom 20 and the like.

Here, the operation control unit 54 controls the operation signal of the work operation device 70, the position information of the tip of the boom 20 calculated by the position calculation unit 51, and the allowable work range S stored in the work range setting unit 53. When it is determined that the tip of the boom 20 has reached the outer edge (limit line) of the allowable work range S by comparing with the information, the tip of the boom 20 is moved outside the allowable work range S. to regulate the actuation of such hydraulic actuators (ignoring such operation signals).

Further, the operation control unit 54 controls that the height of the lift limit line L17 in a part of the allowable work range S (the rear work range S2, the rear left work range S7, and the rear right work range S8) is the regulation height. If the height is restricted to Hb, even if the height of the tip of the boom 20 does not reach the reference height Ha within the working range, the tip of the boom 20 will be lifted when it reaches the restricted height Hb. Actuation of the hydraulic actuator that causes the part to rise above the regulated height Hb is restricted (such an operation signal is ignored). Specifically, when the tip portion of the boom 20 reaches the regulated height Hb, the lifting operation and extension operation of the boom 20 are restricted as the operation for raising the tip portion of the boom 20 . However, even if the tip of the boom 20 reaches the regulated height Hb, the pivoting operation of the boom 20 is not restricted, and the tip of the boom 20 is allowed to pivot horizontally. This is because even if the boom 20 is rotated, the height limit Hb is not exceeded and the safety of the work is ensured.

As described above, according to the present embodiment, in the traveling work posture, when the extension amount of any one of the plurality of roller jacks 10 is the minimum extension amount, the entire allowable work range S set around the vehicle body 2 (without simultaneously reducing both the working radius and the lift), the tip of the boom 20 is is maintained at the reference height Ha, while in the rear working range S2, the limit value of the height at which the tip of the boom 20 can be moved is limited to the regulation height Hb. , the entire allowable work range S is not subject to height regulation, and a wide work radius equivalent to that before the height regulation can be secured, so that the operator's usability is improved, and the road surface inclination is improved. Regardless, it is possible to stably support the vehicle body 2 and improve the safety of the work.

Further, in the present embodiment, when the left side roller jack 10 out of the plurality of roller jacks 10 has the minimum protrusion amount in the traveling work posture, the rear side work range S2 and the rear left side work range S7 When the limit value of the height at which the tip portion of the boom 20 can be moved across is restricted to the regulation height Hb, and the extension amount of the right roller jack 10 is the minimum extension amount, the rear working range S2 And by limiting the limit value of the height at which the tip of the boom 20 can be moved across the rear right working range S8 to the regulation height Hb, the lift is adjusted according to the arrangement of the roller jack 10 that has the minimum overhang amount. By expanding the work range that limits the height of the roller jack 10, the vehicle body 2 can be stably supported regardless of the extension amount of the roller jack 10, so that work safety can be further improved.

It should be noted that the present invention is not limited to the above-described embodiments, and can be modified as appropriate without departing from the gist of the present invention.

In the above embodiment, when the extension amount of the roller jacks 10 (outriggers 11) is the minimum extension amount, the lift limit value of the rear working range S2 and the rear left working range S7 (or the rear right working range S8) is is limited to the regulated height Hb, but it is not limited to this configuration, and the extension amount of the roller jack 10 (outrigger 11) is an intermediate extension amount (intermediate 1 extension amount or intermediate 2 extension amount). In some cases, the limit value of the lift of the rear working range S2 and the rear left working range S7 (or the rear right working range S8) may be restricted to the restricted height Hb.

Further, in the above-described embodiment, when the extension amount of the roller jacks 10 (outriggers 11) is the minimum extension amount, the operation of limiting the limit value of the lifting height according to the arrangement (left and right positions) of the roller jacks 10 is performed. As a range, in addition to the rear side work range S2, the rear left side work range S7 or the rear right side work range S8 is selectively added, but it is not limited to this configuration. Regardless, only the rear working range S2 is always set as the working range to limit the lift limit value, or the rear working range S2, the rear left working range S7 and the rear right working range S8 are always set to limit the lift limit value. It may be a work range to be performed. Further, as in the above-described embodiment, the front working range S1 may also be configured to limit the limit value of the lift. In a front-retractable aerial work vehicle in which the boom is retracted and stored in front of the vehicle body, the front and rear sides are reversed, so the height of only the front working range S1 may be restricted.

Further, in the above embodiment, the lifting height of the rear working range S2 and the lifting height of the rear left working range S7 or the rear right working range S8 are restricted by the same restricted height Hb, but it is limited to this configuration. Instead, the lift of the rear working range S2 is limited by the restricted height Hb1, and the lift of the rear left working range S7 or the rear right working range S8 is restricted by the restricted height Hb2 (preferably Hb2>Hb1). may be configured.

Further, in the above-described embodiment, the telescopic boom type aerial work vehicle has been exemplified and explained as the aerial work vehicle according to the present invention, but the present invention is not limited to this. It may be a work vehicle or the like, and the present invention can be applied to at least a boom-type aerial work vehicle that can freely hoist and turn. In addition, as the aerial work vehicle according to the present invention, an electrically driven (battery driven) aerial work vehicle and a PTO driven type in which the power of the engine is taken out by a PTO mechanism (power take-off mechanism) to drive a hydraulic pump aerial work vehicle, or a hybrid aerial work vehicle that has both of them and selectively switches the power source. In addition, in the above-described embodiment, the rear retractable aerial work vehicle in which the boom is retracted to the rear side of the vehicle body is exemplified. aerial work platform may be applied.

1 aerial work vehicle 2 vehicle body 5 swivel base 10 roller jack (roller jack device)
11 outrigger (outrigger beam)
12 Jack 13 Roller 14 Jack Base 20 Boom 40 Workbench 50 Control Unit 51 Position Calculation Section 52 Work Posture Determination Section 53 Work Range Setting Section (Work Range Setting Means)
54 operation control section (operation control means)
60 position detection device (position detection means)
65 Jack projection amount detector (projection amount detection means)
66 Jack base switching detector 70 Work operating device (operating device)
S Allowable work range S1 Front work range S2 Rear work range S3 Left work range S4 Right work range S5 Front left work range S6 Front right work range S7 Rear left work range (first intermediate work range)
S8 Rear right working range (second intermediate working range)
L17 lift limit line

Claims (2)

a vehicle body having wheels and capable of traveling; a boom provided on the vehicle body so as to be capable of hoisting and turning; an operating device for operating the boom; and a plurality of roller jack devices having jacks that are arranged at the tip of the outrigger beam and extendable below the vehicle body, and rollers that are rotatable in the running direction of the vehicle body at the lower ends of the jacks. is provided, and the vehicle body is configured to be able to travel in a state where the rollers are grounded while the wheels are grounded and the vehicle body is supported by the plurality of roller jack devices,
position detection means for detecting the position of the tip of the boom;
an extension amount detection means for detecting an amount of extension of the outrigger beams to the side of the vehicle body;
As an allowable work range in which the tip portion of the boom is allowed to move outside the vehicle body, a front work range and a rear work range are set in front and rear of the vehicle body, and left and right sides of the vehicle body. working range setting means for setting the left working range and the right working range in
an operation control means for controlling the operation of the boom based on an operation signal from the operating device;
A predetermined reference height is set in the allowable work range as a limit value of the height at which the tip of the boom can be moved,
The working range setting means has a height that allows the distal end portion of the boom to be moved within the rear side working range when the amount of extension of any one of the outrigger beams of the plurality of roller jack devices is less than a predetermined amount. Limiting the limit value of to a regulation height set lower than the reference height,
The operation control means is configured such that, when the amount of extension of any one of the outrigger beams of the plurality of roller jack devices is less than a predetermined amount, the tip portion of the boom exceeds the regulated height within the rear working range. A safety device for an aerial work vehicle, characterized in that it regulates the operation of the boom that moves upward by means of a boom. The work range setting means sets a first intermediate work range between the left work range and the rear work range, and sets a second intermediate work range between the right work range and the rear work range. and set
When the outrigger beam of the left roller jack device out of the plurality of roller jack devices has an amount of extension less than a predetermined amount, the work range setting means extends between the rear side work range and the first intermediate work range. When the height to which the tip of the boom can be moved is limited to the regulated height, and the amount of extension of the outrigger beam of the right roller jack device among the plurality of roller jack devices is less than a predetermined amount, 2. The aerial work platform according to claim 1, wherein a height at which the tip portion of the boom can be moved across the rear working range and the second intermediate working range is restricted to the restricted height. safety equipment.

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