JP2022110797A - Safety device of aerial work platform vehicle - Google Patents

Abstract

To provide a safety device of an aerial work platform vehicle capable of improving the safety in work.SOLUTION: A safety device of an aerial work platform vehicle includes a winch load calculation unit 205 detecting a winch load acting on a winch mechanism (a winch driving motor 78) through a rope and a winch operation regulation unit 206 regulating winding operation of the winch mechanism when the winch load detected by the winch load calculation unit 205 exceeds a regulation load set in advance. The regulation load is set to a winch load in the case where a vehicle body does not fall down even when the tensile force in an outward direction having a horizontal component (for example, the tensile force outward in an obliquely downward direction) acts on the rope through the winding operation of the winch mechanism.SELECTED DRAWING: Figure 4

Description

TECHNICAL FIELD The present invention relates to a safety device for a vehicle for high-elevation work, in which a lifting device having a workbench and a sub-boom is provided at the tip of a boom provided on a vehicle body.

An aerial work vehicle for working at a desired height position includes a boom mounted on the vehicle body so as to be able to move up and down at least, and a work platform attached to the tip of the boom via a work platform support member. and a lifting device provided on the upper part of the workbench support member. The hoisting device includes a revolving section that is horizontally rotatable above the workbench support member, a sub-boom support member that is attached to the revolving section, and a sub-boom that is attached to the sub-boom support member so that it can swing vertically. is configured with Such a hoisting device further comprises a winch mechanism, and the winch mechanism is used to wind up and let out a rope hung on a sheave (guide pulley) at the tip of the sub-boom to lift work members and the like. (See, for example, Patent Documents 1 to 3).

Such an aerial work vehicle is provided with a safety device that prevents the vehicle body from becoming unstable due to an excessive moment acting on the vehicle body from the boom. As an example of this safety device, there is known a moment limiter control that restricts the operation of the boom in the direction in which the moment increases when the moment reaches a predetermined limit value. The moment acting on the vehicle body is calculated, for example, based on the magnitude of the axial force of the hoisting cylinder that hoists the boom up and down. Therefore, an axial force detector for detecting the axial force acting on the hoisting cylinder is provided at the upper end of the hoisting cylinder, and the detected information is input to a controller that controls the operation of the boom. The controller calculates the moment acting on the vehicle body from the boom based on the axial force of the hoisting cylinder detected by the axial force detector, and determines whether or not to restrict the operation of the boom.

Japanese Patent Application Laid-Open No. 2000-219500 Japanese Patent No. 3234942 Japanese Patent No. 4349834

By the way, if a hoisting device is used, the sub-boom is pivotally displaced to an oblique position in which the tip side faces obliquely upward, and in a state in which the rope is drawn out obliquely downward from the sheave, the rope is wound up by a winch mechanism to lift the electric wire. It is also possible to perform an operation of pulling obliquely upward (hereinafter referred to as an oblique pulling operation). When performing diagonal pulling work, a diagonally downward reaction force from an electric wire or the like acts on the boom via the rope. However, since the axial force that acts on the hoisting cylinder in response to the diagonally downward reaction force that has a horizontal component varies depending on the boom hoisting angle, an axial force detector is used to detect the diagonally downward reaction force from the electric wire, etc. Accurate detection of force is difficult. Therefore, there is a possibility that the moment acting on the vehicle body cannot be calculated accurately, and the vehicle body becomes unstable and the safety of the work decreases.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a safety device for a vehicle for work at height that can improve the safety of work.

In order to achieve such an object, the safety device for the aerial work platform according to the present invention comprises a vehicle body that can travel, a boom that is provided on the vehicle body so as to be able to move at least up and down, and a boom that is provided at the tip of the boom. A workbench, a sub-boom provided at the tip of the boom so as to be capable of swinging in the vertical direction, a sheave provided at the tip of the sub-boom, and a rope that is hung on the sheave is wound up and pulled out. A winch load detection unit (for example, the winch load calculation unit 205 in the embodiment and the winch a hydraulic pressure detector 255, etc.), and a winch operation restricting unit that restricts the winding operation of the winch device when the winch load detected by the winch load detecting unit exceeds a preset restricting load. The load is set to the winch load when the vehicle body does not overturn even when a pulling force having a horizontal component is applied to the rope due to the winding operation of the winch device.

In the aerial work vehicle safety device described above, the regulated load is the winch load applied when the vehicle body does not overturn even if a horizontal outward tensile force acts on the rope due to the winding operation of the winch device. It is preferably set to load.

In the above-described safety device for aerial work vehicle, when the winch load detected by the winch load detection unit exceeds the regulated load, the winch operation regulating unit regulates the winding operation of the winch device in a regulation mode (for example, , winding mode in the embodiment) and a non-restriction mode in which the winch operation restriction unit is in a non-operating state (e.g., high altitude mode in the embodiment). changeover switch SW9), a moment detection unit for detecting the moment acting on the vehicle body (for example, the moment calculation unit 203 and the axial force detector 254 in the embodiment), and a position detection unit for detecting the position of the workbench ( For example, the position calculator 204, the boom hoisting angle detector 251, the boom length detector 252, and the boom turning angle detector 253, etc. in the embodiment), and the operation of the switch switches to the non-restricted mode. when the moment detected by the moment detection unit exceeds a preset regulated moment, and when the changeover switch is operated to switch to the regulated mode, the position It is preferable to include a boom operation restricting unit that restricts operation of the boom such that the position of the workbench detected by the detecting unit exceeds a preset allowable work range.

According to the present invention, the regulating load in the winch operation regulating portion is set to the winch load in the case where the vehicle body does not overturn even if a pulling force having a horizontal component acts on the rope to the outside due to the winding operation of the winch device. be done. As a result, as the outward tensile force having a horizontal component, the winch operation restricting part determines the winch load when the vehicle body does not overturn even if the diagonally downward outward tensile force acts on the rope. By restricting the winding operation of the winch device, the vehicle body does not become unstable even when performing diagonal pulling work, and the safety of the work can be improved.

In addition, if a hoisting device is used, the sub-boom is pivotally displaced to a vertical position in which the tip side faces vertically upward (vertically upward), and the rope is reeled out by the winch mechanism in a state in which the rope is drawn out horizontally from the sheave. It is also possible to perform a work of pulling a wire or the like in a horizontal direction (hereinafter referred to as a horizontal pulling work). When performing horizontal pulling work, the regulated load in the winch operation regulating section is set to the winch load that does not overturn the car body even if a pulling force acting on the rope in the horizontal direction is applied to the rope due to the winding operation of the winch device. be. As a result, the winch load is determined by the winch operation restricting portion as the outward tensile force having a horizontal component, based on the winch load when the vehicle body does not overturn even if the horizontal outward tensile force acts on the rope. By restricting the winding operation of the device, even when performing horizontal pulling work, the vehicle body does not become unstable, making it possible to improve work safety.

Note that the obliquely downward reaction force from the electric wire or the like acting on the boom is divided into a horizontal component and a vertical component of the reaction force. As a result, part of the reaction force acting on the boom is received by the boom as compression force. It is smaller in the case of performing the diagonal pulling work than in the case of performing the pulling work. Therefore, the winch operation restricting part restricts the winding operation of the winch device based on the winch load when the vehicle body does not overturn even if the tensile force acting on the rope in the horizontal direction is applied to the rope. Even when performing work, the vehicle body does not become unstable, making it possible to improve work safety.

Further, the boom operation restricting section restricts the operation of the boom such that the moment detected by the moment detecting section exceeds a preset restricting moment when switched to the non-restricting mode, and the boom operation is switched to the restricting mode. In such a case, the operation of the boom is regulated such that the position of the workbench detected by the position detection unit exceeds a preset allowable work range. As a result, when the winch operation restricting unit switches to the restriction mode that can restrict the winding operation of the winch device, the boom operation restricting unit restricts the operation of the boom based on the position of the workbench. Even when performing diagonal pulling work (and horizontal pulling work), the vehicle body does not become unstable due to inability to accurately calculate the moment acting on the vehicle body, and the safety of the work can be improved.

1 is a side view of an aerial work vehicle equipped with a safety device according to an embodiment; FIG. It is a figure which shows the workbench and lifting apparatus of the said aerial work vehicle, (A) is a side view, (B) is a perspective view. It is a figure which shows the upper operating device with which the said workbench was equipped. It is a functional block diagram of the safety device with which the above-mentioned vehicle for work at height was equipped. It is a schematic diagram which shows an example of the allowable working range in the vehicle for aerial work. Fig. 3 is a perspective view showing a workbench and a hoisting device of the aerial work vehicle; It is a perspective view which shows the case where diagonal pulling work is performed using the said lifting apparatus. It is a perspective view which shows the case where horizontal pulling operation|work is performed using the said lifting apparatus.

Preferred embodiments of the present invention will be described below with reference to the drawings. A vehicle for high lift work 1 according to the present embodiment is shown in FIG.

As shown in FIG. 1, the aerial work vehicle 1 has a driving cab 7 in the front part of the vehicle body 2, and is a track that can be driven by a pair of left and right front wheels 5f and rear wheels 5r disposed in front and rear of the vehicle body 2. It is based on a vehicle. The vehicle body 2 includes a chassis frame having front wheels 5f and rear wheels 5r and a sub-frame mounted on the chassis frame.

Jack devices 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 jack device includes a pair of left and right front jacks 10f arranged behind the front wheels 5f and a pair of left and right rear jacks 10r arranged behind the rear wheels 5r. Each of the jacks 10f and 10r drives a jack cylinder 11 provided therein to extend downward to lift and support the vehicle body 2, thereby stabilizing the vehicle as a whole. A rear end portion of the vehicle body 2 is provided with a lower operation device 27 for operating the jacks 10f and 10r, a boom 30 to be described later, and the like.

A swivel base 20 that is driven by a swivel motor 24 and configured to be horizontally swivelable about a vertical axis is provided in the vehicle body 2 behind the cab 7 . A base end of a boom 30 is attached to a post 21 extending upward from the swivel base 20 via a foot pin 22 so as to be vertically swingable (raising and lowering). Tool boxes 26 for storing work tools and work equipment are provided on the left and right sides of the mounting area of the vehicle body 2 .

The boom 30 has a configuration in which a base end boom 30a, an intermediate boom 30b, and a tip boom 30c are telescopically combined in order from the swivel base 20 side. , the boom 30 can be telescopically moved in the axial direction (longitudinal direction). A hoisting cylinder 23 is straddled between the base end boom 30a and the strut 21, and the boom 30 as a whole is hoisted and lowered in the upper and lower planes (vertical plane) by extending and contracting the hoisting cylinder 23. be able to.

As shown in FIGS. 2A and 2B, a vertical post 32 is attached to the tip of the tip boom 30c by a swing pin 33 so as to be vertically swingable. The vertical post 32 is supported by an upper leveling cylinder (not shown) straddled between the tip of the tip boom 30c and a lower leveling cylinder 25 straddled between the base end boom 30a and the post 21. , swing control (leveling control) is performed so that the vertical posture is always maintained regardless of the hoisting angle of the boom 30 .

A workbench bracket 38 is attached to the upper part of the vertical post 32 so as to be able to rotate (horizontally turnable) with respect to the vertical post 32, and the upper part of the workbench bracket 38 is opened via a workbench lifting device 36. A box-shaped workbench 40 is attached. The top of vertical post 32 and workbench bracket 38 are wrapped around by cover 35 . An oscillating motor 34 is provided inside the cover 35. By driving the oscillating motor 34, the work table bracket 38 and the work table 40 are rotated through a rotation transmission mechanism including a worm gear and a wheel gear (not shown). It is configured so that it can be horizontally swiveled (swinged) around the vertical post 32 .

As described above, the vertical post 32 is leveled so that the vertical posture is always maintained, so that the floor surface of the work table 40 is always kept horizontal regardless of the hoisting angle of the boom 30. there is The work table lifting device 36 is configured to have a lifting cylinder (not shown), and is configured to move the work table 40 up and down with respect to the work table bracket 38 by driving the lifting cylinder. there is

The workbench 40 is provided with an upper operation device 45 having various operation means such as operation levers and switches to be operated by a worker on the workbench 40 . Therefore, by operating the upper operation device 45, a worker on the workbench 40 can turn the swivel base 20 (rotating operation of the turning motor 24) and raise and lower the boom 30 (extend and contract operation of the raising and lowering cylinder 23). , expansion and contraction of the boom 30 (extension and contraction of the telescopic cylinder 31), swinging of the workbench 40 (rotating of the swinging motor 34), and the like.

Actuating mechanisms of aerial work equipment and the like (the above-described swivel base 20, boom 30, workbench 40, etc.) provided on the vehicle body 2 receive operation signals from the upper operation device 45 and the lower operation device 27, and operate the jack cylinder. 11. A controller that controls the swing motor 24, the telescopic cylinder 31, the hoisting cylinder 23, the swing motor 34, and the lifting cylinder (not shown) of the work table lifting device 36 (hereinafter collectively referred to as "hydraulic actuator 55"). 200 (see FIG. 4), a hydraulic unit 50 (see FIG. 4) that supplies hydraulic oil to operate the hydraulic actuator 55 described above, and an engine E of the vehicle body 2 for driving aerial work equipment and the like. (See FIG. 4).

As shown in FIG. 4, the hydraulic unit 50 includes a hydraulic pump 51, a power take-off mechanism 52 for driving the hydraulic pump 51, and a supply direction and amount of hydraulic oil supplied from the hydraulic pump 51 to each hydraulic actuator 55. and a control valve 53 for controlling the The power take-off mechanism 52 is incorporated in a transmission (not shown) that shifts the power of the engine E of the vehicle body 2 and transmits it to the rear wheels 5r. When a PTO control lever (not shown) provided in the driving cab 7 is operated from the OFF position to the ON position, the power take-off mechanism 52 switches the driving destination of the engine E from the rear wheels 5r to the hydraulic pump 51. , the power of the engine E is used to drive the hydraulic pump 51 . The control valve 53 supplies hydraulic fluid from the hydraulic pump 51 to each hydraulic actuator 55 in response to a control signal from the controller 200 (a control signal corresponding to the operation signals from the upper operation device 45 and the lower operation device 27). It controls the direction and amount of feed, and controls the direction and speed of actuation of each hydraulic actuator 55 (controls the direction and speed of actuation of jacking equipment and aerial work equipment).

Although not shown in detail, the hydraulic unit 50 is provided with a second hydraulic pump (not shown) driven by an electric motor (not shown). The electric motor is rotationally driven by electric power supplied from the mounting section battery 59 via an inverter. In place of the (first) hydraulic pump 51 driven by the engine E of the vehicle body 2 and the power take-off mechanism 52 , the hydraulic unit 50 drives a second hydraulic pump to each hydraulic actuator 55 in response to a control signal from the controller 200 . It is configured to be able to control the supply direction and supply amount of the hydraulic oil supplied to the hydraulic actuator 55 and to control the operating direction and operating speed of each hydraulic actuator 55 .

Also, as shown in FIG. 2A, a lifting device 70 is provided at the upper end of the vertical post 32 . The hoisting device 70 includes a revolving body 71 that is horizontally rotatable on the upper end of the vertical post 32, a sub-boom support member 72 that is attached to the upper part of the revolving body 71 so as to be able to swing vertically, and a sub-boom support member 72. and a long sub-boom 74 detachably attached to the upper part of the. The sub-boom 74 is removed from the sub-boom support member 72 and attached to the base end boom 30a as shown in FIG. 1, for example, when the aerial work vehicle 1 is moved.

The revolving body 71 includes a revolving member 71a rotatably attached to the upper end of the vertical post 32 and a cover 71b covering the revolving member 71a. The turning member 71a is provided so as to be able to turn coaxially with the turning axis A of the workbench 40 (workbench bracket 38) by driving a winch turning motor 76 (see FIG. 4) provided therein. A horizontally extending rocking pin 72a is provided on the upper portion of the turning member 71a, and a sub-boom support member 72 is attached so as to be vertically rockable about the rocking pin 72a.

By driving a sub-boom hoisting cylinder 77 (see FIG. 4) provided inside the cover 71b of the revolving body 71, the sub-boom support member 72 is vertically moved with respect to the revolving member 71a around the swing pin 72a. It is configured to be swingable. A sub-boom mounting hole (not shown) extending in a direction orthogonal to the swing pin 72a is formed in the upper portion of the sub-boom support member 72. A sub-boom 74 is inserted into this sub-boom mounting hole and is supported by a fixing pin 77. It is fixedly held by the member 72 . As a result, the sub-boom 74 is moved to a horizontal position (Fig. 2 (A
)) and a vertical position (see FIG. 8) in which the tip side of the sub-boom 74 faces vertically upward. The length of sub-boom 74 extending from sub-boom support member 72 toward workbench 40 in FIG.

At the upper end of the sub-boom support member 72, a winch rope 79 (see FIGS. 6 to 8), which is wound around a sheave member 74a (a guide pulley) provided at the tip of the sub-boom 74, is fed out and wound up. A winch mechanism 75 is provided to do so. The winch mechanism 75 is configured to extend and wind up the winch rope 79 by driving a built-in winch drive motor 78 (see FIG. 4). A hook 79a (see FIGS. 6 to 8) is attached to the tip of the winch rope 79. As shown in FIG.

As for the winch swing motor 76, the sub-boom hoisting cylinder 77, and the winch drive motor 78, the operation of the control valve 53 is controlled by the controller 200 that receives the operation signal from the upper operation device 45, similarly to the hydraulic actuator 55 described above. . The control valve 53 controls the direction and amount of hydraulic oil supplied from the hydraulic pump 51 (or the aforementioned second hydraulic pump), thereby controlling the winch swing motor 76, the sub-boom hoisting cylinder 77, and the winch. The operating direction and operating speed of the drive motor 78 (hereinafter collectively referred to as "sub-boom actuator 56") are controlled.

Next, the upper operating device 45 according to this embodiment will be described with reference to FIG. The upper operation device 45 includes a box-shaped operation box 45a attached to the workbench 40, a joystick JS, various operation levers LV1 to LV6, and various switches SW1 to SW11. Note that FIG. 3 shows a part of the upper portion of the operation box 45a. On the upper side of the operation box 45a near the center of the workbench 40, in order from the right side of FIG. A sub-boom turning operation lever LV4, a lifting operation lever LV5, and an attachment switching operation lever LV6 are provided.

The joystick JS is an operating device for turning the swivel base 20 , raising and lowering the boom 30 , and extending and retracting the boom 30 . The swing operation lever LV1 is an operation lever for swinging the workbench 40 . The winch operation lever LV2 is an operation lever for extending the winch mechanism 75 and winding the winch mechanism 75 . The sub-boom swing operation lever LV3 is an operation lever for causing the sub-boom 74 to swing. The sub-boom turning operation lever LV4 is an operation lever for turning the turning member 71a. The elevation operation lever LV5 is an operation lever for raising and lowering the workbench 40 . The attachment switching operation lever LV6 is an operation lever for switching various attachments (not shown).

On the upper side of the operation box 45a near the outer periphery of the workbench 40, in order from the right side of FIG. , an automatic retraction switch SW6, a horizontal/vertical operation switch SW7, an interference prevention function release switch SW8, and a mode changeover switch SW9. In addition, a lighting switch SW10 and a battery check switch SW11 are provided in order from the right side of FIG.

The operation stop switch SW1 is an operation switch for stopping the operation of the aerial work equipment (swivel base 20, boom 30, work table 40, etc.). The operation stop switch SW1 is configured using a push-pull type button switch or the like, and is pushed to stop the operation of the aerial work equipment, etc., and pulled to release the stopped state of the aerial work equipment, etc. It is possible. An operation stop lamp LP1 is provided between the operation stop switch SW1 and the power switch SW2 in the upper portion of the operation box 45a. When the operation stop switch SW1 is pushed to stop the operation of the aerial work equipment or the like, the operation stop lamp LP1 is turned on.

The power switch SW2 is an operation switch for turning on/off the power of the upper operation device 45 . The drive selector switch SW3 is driven by a (first) hydraulic pump 51 driven by the engine E of the vehicle body 2 and a power take-off mechanism 52, and by an electric motor (not shown). It is an operation switch for switching to a second hydraulic pump (not shown). The engine switch SW4 is an operation switch for starting or stopping the engine E. The accelerator switch SW5 is an operation switch for switching between an automatic mode in which the rotation speed of the engine E is automatically controlled to increase or decrease, and a low speed mode in which the rotation speed of the engine E is controlled to a constant low rotation speed.

The automatic retraction switch SW6 is an operation switch for causing the controller 200 to perform automatic retraction control for retracting the boom 30 to a predetermined retraction position on the vehicle body 2 . The horizontal/vertical operation switch SW7 is an operation switch for causing the controller 200 to perform horizontal/vertical operation control for linearly moving the workbench 40 in the horizontal direction or the vertical direction. The interference prevention function cancellation switch SW8 is an operation switch for temporarily canceling the interference prevention function. Note that the interference prevention function is a function of setting an interference prevention regulation area in which movement of the workbench 40 is regulated in order to prevent contact with an obstacle or the like. The power switch SW2, the drive changeover switch SW3, the engine switch SW4, the accelerator switch SW5, the automatic retraction switch SW6, the horizontal/vertical operation switch SW7, and the interference prevention function release switch SW8 are configured using toggle switches or the like.

The mode changeover switch SW9 is an operation switch for switching between a high altitude mode and a winding mode. The mode changeover switch SW9 is configured using a toggle switch or the like, and can be switched in order from the high altitude mode to the winding mode, the high altitude mode, the winding mode, . . . The high altitude mode is a control mode in which high altitude work and the like can be performed. The winding mode is a control mode in which the lifting device 70 can be used to perform diagonal pulling work (or horizontal pulling work).

Further, by pressing and holding the mode switching switch SW9 in the winding mode, the winding mode can be switched to the pre-use inspection mode. Further, by pressing and holding the mode changeover switch SW9 in the pre-use inspection mode, the pre-use inspection mode can be switched to the winding mode. The pre-use inspection mode is a control mode for performing pre-use inspection in the winding mode. Note that the mode changeover switch SW9 is not limited to a toggle switch, and may be configured using a push button switch, a rotary switch, or the like.

The illumination switch SW10 is an operation switch for turning on/off an illumination lamp (not shown) that illuminates the upper portion of the upper operation device 45 . The battery check switch SW11 is an operation switch for turning on/off the battery check lamp LP2. The illumination switch SW10 and the battery check switch SW11 are configured using toggle switches or the like. A battery check lamp LP2 is provided beside the battery check switch SW11 in the upper portion of the operation box 45a (to the left in FIG. 3). The battery check lamp LP2 lights and displays the remaining amount of the upper battery (not shown) provided on the workbench 40 in two stages by lighting operation of the battery check switch SW11. In addition, along with the battery check lamp LP2, a load factor display lamp LP3, a battery unit remaining amount display lamp LP4, and a winding A mode indicator lamp LP5 and a temporary support mode indicator lamp LP6 are provided.

When the high-altitude mode is switched to the winding mode by pressing the mode switching switch SW9, the winding mode display lamp LP5 lights up. When the winding mode is switched to the high altitude mode by pressing the mode switching switch SW9, the winding mode display lamp LP5 is extinguished. Further, when the winding mode is switched to the pre-use inspection mode by pressing the mode switching switch SW9 for a long time, the winding mode display lamp LP5 blinks.

Next, a safety device (overturn prevention device) provided in the aerial work platform 1 will be described with reference to FIGS. 4 and 5. FIG. The safety device according to this embodiment includes various sensors and a controller 200, as shown in FIG.

As shown in FIG. 4, the sensors include a boom hoisting angle detector 251, a boom length detector 252, a boom turning angle detector 253, an axial force detector 254, a winch oil pressure detector 255, and a jack. It consists of an overhang amount detector 256 and the like. These detectors are electrically connected to the controller 200 , and detection information (detection signals) of the detectors 251 to 256 are input to the controller 200 .

The boom hoisting angle detector 251 is provided at the base end of the boom 30 and detects the hoisting angle of the boom 30 . The boom length detector 252 is provided inside the boom 30 and detects the length (extension amount) of the boom 30 . The boom turning angle detector 253 is provided on the vehicle body 2 and detects the turning angle of the boom 30 (swivel base 20). The axial force detector 254 is provided at the upper end of the hoisting cylinder 23 and detects the axial force (axial load) acting on the hoisting cylinder 23 . The winch oil pressure detector 255 is provided in a winch control valve (not shown) that controls the supply direction and amount of hydraulic oil supplied to the winch drive motor 78 in the control valve 53, and is supplied to the winch drive motor 78. Detects hydraulic pressure of hydraulic oil. The jack extension detector 256 is provided on the vehicle body 2 and detects the extension of the jacks 10f and 10r.

The controller 200 includes an operation control unit 201, an engine control unit 202, a moment calculation unit 203, a position calculation unit 204, a winch load calculation unit 205, a winch operation restriction unit 206, a boom operation restriction unit 207, a mode It has a determination unit 208 and an abnormality determination unit 209 . The units 201 to 209 of the controller 200 are functional representations of hardware such as CPU, ROM, RAM, and electronic circuits provided in the controller 200 and software such as control programs. .

The operation control unit 201 electromagnetically drives the control valve 53 based on an operation signal from the upper operation device 45 or the lower operation device 27 to operate the hydraulic actuators 55 and the sub-boom actuators 56 to operate the jacks 10f and 10f. 10r, boom 30, workbench 40, sub-boom 74, winch mechanism 75, etc. are controlled.

The engine control unit 202 performs control to start the engine E when a start operation signal for the engine E is input from the engine switch SW4 of the upper operation device 45 (or the engine switch of the lower operation device 27). When the stop operation signal is input, control to stop the engine E is performed. Further, when a switching operation signal for switching to the automatic mode is input from the accelerator switch SW5 of the upper operating device 45 (or the accelerator switch of the lower operating device 27), the engine control unit 202 automatically changes the rotation speed of the engine E to high or low. When a switching operation signal for switching to the low speed mode is input, the rotation speed of the engine E is controlled to a constant low speed rotation speed. Note that when a switching operation signal for switching to the winding mode is input from the mode switching switch SW9 of the upper operating device 45, the engine control unit 202 changes the rotation speed of the engine E regardless of the operation signal from the accelerator switch SW5. is controlled to a constant low speed.

The moment calculation unit 203 detects the axial force of the hoisting cylinder 23 detected by the axial force detector 254, the hoisting angle of the boom 30 detected by the boom hoisting angle detector 251, and other detected information such as the foot pin 22 of the boom 30. Calculate the moment acting around (around the hoisting axis). This moment is obtained by converting the axial force acting on the hoisting cylinder 23 into a moment acting around the foot pin 22 . That is, this moment acts on the hoisting cylinder 23 as the moment acting on the vehicle body 2 due to the dead weight of the boom 30 and the work table 40, etc., the load applied to the work table 40, the lifting load when using the lifting device 70, and the like. It is calculated based on the axial force.

The position calculator 204 calculates the hoisting angle of the boom 30 detected by the boom hoisting angle detector 251, the length of the boom 30 detected by the boom length detector 252, and the boom 30 detected by the boom turning angle detector 253. The position of the bottom of the workbench 40 (or the tip of the boom 30) with respect to the vehicle body 2 is calculated based on the detected information such as the turning angle. The winch load calculator 205 calculates the winch load acting on the winch mechanism 75 via the winch rope 79 based on the detection information of the hydraulic pressure of the hydraulic oil supplied to the winch drive motor 78 detected by the winch hydraulic pressure detector 255 . Calculate

When a switching operation signal for switching to the winding mode is input from the mode switching switch SW9 of the upper operating device 45, the winch operation restricting unit 206 sets the winch load calculated by the winch load calculating unit 205 to the preset restricting load. Compare with When the winch load calculated by the winch load calculation unit 205 exceeds the limit load, the winch operation restricting unit 206 activates the winch mechanism 75 (winch drive motor 78) regardless of the operation signals from the operation devices 27 and 45. Regulate (stop) the winding operation. In this embodiment, the regulated load is set to the winch load when the vehicle body 2 does not overturn even if the winch rope 79 is subjected to an obliquely downward outward tensile force due to the winding operation of the winch mechanism 75 .

When a switching operation signal for switching to the high altitude mode is input from the mode switching switch SW9 of the upper operating device 45, the winch operation restricting unit 206 compares the winch load and the restricted load, and controls the winch mechanism 75 (winch drive motor 78). No winding operation regulation is performed. That is, the winch operation restricting portion 206 is put into a non-operating state when a switching operation signal for switching to the high altitude mode is input from the mode switching switch SW9 of the upper operating device 45 .

When a switching operation signal for switching to the high altitude mode is input from the mode switching switch SW9 of the upper operating device 45, the boom operation restricting section 207 compares the moment calculated by the moment calculating section 203 with the preset restricted moment. compare. When the moment calculated by the moment calculating unit 203 reaches the regulated moment, the boom operation restricting unit 207 acts on the boom 30 during the operation of the boom 30 regardless of operation signals from the operating devices 27 and 45. It regulates the movement in the direction in which the overturning moment increases (lowering movement, extension movement, turning movement in a predetermined direction). Note that the regulated moment is set according to the turning angle of the boom 30, the extension amount of the jacks 10f and 10r, and the like.

When a switching operation signal for switching to the winding mode is input from the mode switching switch SW9 of the upper operating device 45, the boom operation restricting unit 207 changes the position of the work table 40 (bottom) calculated by the position calculating unit 204 and the Compare with the set allowable working range. When the position of the workbench 40 calculated by the position calculation unit 204 reaches the outer edge of the allowable work range, the boom operation regulation unit 207 regulates the boom 30 regardless of the operation signals from the operation devices 27 and 45. Among the operations, the operation in the direction in which the workbench 40 moves outside the allowable work range is restricted. FIG. 5 shows an allowable work range S in the vertical plane as an example of the allowable work range. In FIG. 5, the vertical axis of the graph showing the allowable working range S indicates the height of the workbench 40 (bottom), and the horizontal axis of the graph showing the allowable working range S indicates the center of rotation of the boom 30 (swivel base 20). The working radius centered on C is shown. The allowable work range S in the present embodiment is set to the allowable work range in which the vehicle body 2 does not overturn even if a pulling force acting on the winch rope 79 in an obliquely downward outward direction due to the winding operation of the winch mechanism 75 is applied. be. It should be noted that the allowable work range S is set according to the extension amount of the jacks 10f and 10r.

When a switching operation signal for switching to the winding mode is input from the mode switching switch SW9 of the upper operating device 45, the mode determination unit 208 determines that the extension amounts of the jacks 10f and 10r detected by the jack extension amount detector 256 are It is determined whether or not the position of the workbench 40 (bottom) calculated by the position calculation unit 204 is larger than the preset regulation overhang amount and is within the allowable work range. Mode determination unit 208 outputs a normal notification signal to upper operation device 45 when the determination is YES. When the determination is NO, that is, when the extension amount of the jacks 10f and 10r is equal to or less than the regulated extension amount or the work table 40 is located outside the allowable work range in the winding mode. , outputs an abnormality notification signal to the upper operating device 45 and outputs an operation stop signal for stopping the operation of each hydraulic actuator 55 and the sub-boom actuator 56 to the operation control unit 201 .

When a switching operation signal for switching to the pre-use inspection mode is input from the mode switching switch SW9 of the upper operating device 45, the abnormality determination unit 209 receives an operating operation signal input from the winch operating lever LV2 of the upper operating device 45, and the winch hydraulic pressure. Based on the detection signal or the like input from the detector 255, it is determined whether or not the hydraulic pressure detected by the winch hydraulic pressure detector 255 increases due to the extension and winding operations of the winch mechanism 75 (winch drive motor 78). do. Abnormality determination unit 209 outputs a normality notification signal to upper operating device 45 when the determination is YES. Abnormality determination unit 209 outputs an abnormality notification signal to upper operating device 45 when the determination is NO, that is, when the hydraulic pressure detected by winch hydraulic pressure detector 255 does not increase in the pre-use inspection mode. Further, the abnormality determination section 209 may output to the operation control section 201 an operation stop signal for stopping the operation of each sub-boom actuator 56 .

Next, with reference to FIG. 6 and FIG. 7, the control in the case of switching from the high altitude mode to the winding mode and performing the diagonal pulling work will be described. In the high altitude mode, the operation control section 201 of the controller 200 electromagnetically drives the control valve 53 based on the operation signal from the upper operation device 45 or the lower operation device 27 to operate each hydraulic actuator 55 and the sub-boom actuator 56. By actuating it, it controls the operations of the jacks 10f and 10r, the boom 30, the workbench 40, the sub-boom 74, the winch mechanism 75, and the like.

When the boom 30 is raised with respect to the vehicle body 2 and the work member or the like is to be lifted, the operator OP on the workbench 40 has the front end side obliquely upward as shown in FIG. , and the winch rope 79 is let out vertically downward from the sheave member 74a. At this time, a moment acts on the vehicle body 2 due to the weight of the boom 30 and the workbench 40, etc., the load applied to the workbench 40, the hoisting load applied to the hoisting device 70, and the like.

In the high altitude mode, the boom operation restricting section 207 of the controller 200 compares the moment calculated by the moment calculating section 203 with a preset restricted moment. When the moment calculated by the moment calculating unit 203 reaches the regulated moment, the boom operation restricting unit 207 acts on the boom 30 during the operation of the boom 30 regardless of operation signals from the operating devices 27 and 45. It regulates the operation in the direction in which the overturning moment increases. In addition, in the high altitude mode, the winch operation restricting section 206 of the controller 200 is in a non-operating state.

Further, when the boom 30 is raised with respect to the vehicle body 2 to carry out the work of diagonally pulling the electric wire laid between utility poles, the operator OP on the workbench 40 has a tip side as shown in FIG. The sub-boom 74 is pivotally displaced to an oblique position facing obliquely upward, the hook 79a is hooked on an electric wire (not shown), and the winch rope 79 is extended obliquely downward from the sheave member 74a. 79 winding is performed. When performing diagonal pulling work, a diagonally downward reaction force from the electric wire acts on the boom 30 via the winch rope 79 . However, since the axial force acting on the hoisting cylinder 23 in response to the diagonally downward reaction force having a horizontal component varies depending on the hoisting angle of the boom 30, the axial force detector 254 is used to detect the slanting downward force from the electric wire. It is difficult to accurately detect the reaction force of Therefore, there is a possibility that the moment calculation unit 203 cannot accurately calculate the moment acting on the vehicle body 2 and the vehicle body 2 becomes unstable and the safety of the work decreases.

Therefore, when performing the diagonal pulling work of the electric wire laid between utility poles, the operator OP on the workbench 40 operates the upper operating device 45 to switch from the high altitude mode to the winding mode. In order to switch from the high place mode to the winding mode, first, the operator OP presses the operation stop switch SW1 of the upper operating device 45 to turn on the high place work equipment (swivel base 20, boom 30, work equipment, etc.). 40 etc.) is stopped. Next, the operator OP pushes the mode changeover switch SW9 of the upper operating device 45 only once, and then pulls the operation stop switch SW1 to operate the aerial work equipment. Release the suspended state. At this time, the mode switching switch SW9 outputs to the controller 200 a switching operation signal for switching from the high altitude mode to the winding mode.

When a switching operation signal for switching from the high-altitude mode to the winding mode is input to the controller 200, the mode determination unit 208 of the controller 200 determines that the extension amounts of the jacks 10f and 10r detected by the jack extension amount detector 256 are It is determined whether or not the position of the workbench 40 (bottom) calculated by the position calculation unit 204 is larger than the preset regulation overhang amount and is within the allowable work range. If the determination is NO, the mode determination unit 208 outputs an abnormality notification signal to the upper operation device 45 and outputs an operation stop signal for stopping the operation of each hydraulic actuator 55 and the sub-boom actuator 56 to the operation control unit 201 . As a result, the operation stop lamp LP1 of the upper operating device 45, the winding mode display lamp LP5, and the temporary support mode display lamp LP6 blink alternately to inform the operator OP of the abnormality. The operation control unit 201 also performs control to stop the operation of each hydraulic actuator 55 and sub-boom actuator 56 . Note that when the abnormality notification signal is output from the mode determination unit 208, the operator OP presses the operation stop switch SW1 of the upper operating device 45, and then presses the mode changeover switch SW9. By doing so, it is possible to return to high altitude mode.

On the other hand, mode determination unit 208 outputs a normal notification signal to upper operating device 45 when the determination is YES. As a result, the winding mode display lamp LP5 of the upper operating device 45 is lit, and the operator OP is notified that the winding mode has been switched to. When the normal notification signal is output from the mode determination unit 208, it is possible to switch from the winding mode to the pre-use inspection mode.

To switch from the winding mode to the pre-use inspection mode, the operator OP long-presses the mode switching switch SW9 of the upper operating device 45 . At this time, the mode switching switch SW9 outputs a switching operation signal for switching from the winding mode to the pre-use inspection mode to the controller 200 . In addition, the winding mode display lamp LP5 of the upper operating device 45 flashes to inform the operator OP that the mode has been switched to the pre-use inspection mode.

Next, the operator OP performs a swing motion operation for swinging the sub-boom 74 with respect to the sub-boom swing operation lever LV3 of the upper operating device 45, and as shown in FIG. The sub-boom 74 is pivotally displaced so that the winch rope 79 extends vertically downward from the sheave member 74a. At this time, the actuation control section 201 of the controller 200 electromagnetically drives the control valve 53 to operate the sub-boom hoisting cylinder 77 based on the oscillating operation signal from the sub-boom oscillating operation lever LV3. Controls rocking motion.

Next, the operator OP performs a payout operation to perform a payout operation of the winch mechanism 75 with respect to the winch operation lever LV2 of the upper operating device 45, and the operation is performed for a time equal to or longer than a preset payout time (for example, 3 seconds). The winch rope 79 is let out by the winch mechanism 75 over the entire length. At this time, the operation control unit 201 of the controller 200 electromagnetically drives the control valve 53 to operate the winch drive motor 78 based on the extension operation signal from the winch operation lever LV2, thereby extending the winch mechanism 75. to control. Subsequently, the operator OP performs a winding operation to cause the winch mechanism 75 to perform a winding operation with respect to the winch operation lever LV2, and for a time equal to or longer than a preset winding time (for example, 2 seconds), A winch rope 79 is wound by the winch mechanism 75 . At this time, the operation control unit 201 of the controller 200 electromagnetically drives the control valve 53 to operate the winch drive motor 78 based on the winding operation signal from the winch operation lever LV2, thereby causing the winch mechanism 75 to wind. Controls take action.

When a switching operation signal for switching from the winding mode to the pre-use inspection mode is input to the controller 200, the abnormality determination unit 209 of the controller 200 receives an operation operation signal from the winch operation lever LV2 and the winch oil pressure detector 255. Based on the detected signal and the like, it is determined whether or not the hydraulic pressure detected by the winch hydraulic pressure detector 255 increases due to the extension operation and winding operation of the winch mechanism 75 (winch drive motor 78). The abnormality determination unit 209 outputs an abnormality notification signal to the upper operation device 45 when the determination is NO. As a result, the operation stop lamp LP1 of the upper operating device 45, the winding mode display lamp LP5, and the temporary support mode display lamp LP6 blink alternately to inform the operator OP of the abnormality. When the abnormality notification signal is output from the abnormality determination unit 209, the operator OP presses the operation stop switch SW1 of the upper operating device 45, and then presses the mode switching switch SW9. By doing so, it is possible to return to high altitude mode.

On the other hand, when the determination is YES, the abnormality determination unit 209 outputs a normality notification signal to the upper operating device 45 . As a result, the winding mode display lamp LP5 and the temporary support mode display lamp LP6 of the upper operating device 45 are lit, and the operator OP is notified that no abnormality was detected in the pre-use inspection mode. When the abnormality determination unit 209 outputs a normal notification signal, it is possible to switch from the pre-use inspection mode to the winding mode.

To switch from the pre-use inspection mode to the winding mode, the operator OP long-presses the mode switching switch SW9 of the upper operating device 45 . At this time, the mode switching switch SW9 outputs a switching operation signal for switching from the pre-use inspection mode to the winding mode to the controller 200 . In addition, the temporary support mode display lamp LP6 of the upper operating device 45 is turned off and only the winding mode display lamp LP5 is turned on to inform the operator OP that the winding mode has been switched.

In this way, by switching from the high place mode to the winding mode, it becomes possible to carry out the work of diagonally pulling the electric wire laid between utility poles. When performing diagonal pulling work in the winding mode, the operator OP on the workbench 40 operates the upper operating device 45 so that the sub-boom 74 is positioned diagonally above the electric wire laid between the utility poles. Adjust the position of work platform 40 and sub-boom 74 . At this time, the operation control unit 201 of the controller 200 electromagnetically drives the control valve 53 based on the operation signal from the upper operation device 45 to operate each hydraulic actuator 55 and the sub-boom actuator 56, thereby causing the boom 30 to operate. , the workbench 40, the sub-boom 74, and the like.

In the winding mode, the boom operation restricting section 207 compares the position of the workbench 40 (bottom) calculated by the position calculating section 204 with a preset allowable work range. When the position of the workbench 40 calculated by the position calculation unit 204 reaches the outer edge of the allowable work range, the boom operation regulation unit 207 regulates the boom 30 regardless of the operation signals from the operation devices 27 and 45. Among the operations, the operation in the direction in which the workbench 40 moves outside the allowable work range is restricted. In the winding mode, the operation of the boom 30 is restricted based on the position of the workbench 2 by the boom operation restriction unit 207, so even when performing diagonal pulling work, the moment acting on the vehicle body 2 cannot be accurately calculated. Therefore, the vehicle body 2 does not become unstable, and the safety of work can be improved.

Next, the operator OP performs a swing motion operation on the sub-boom swing operation lever LV3 of the upper operation device 45, and as shown in FIG. Then, the hook 79a is hooked on an electric wire (not shown) so that the winch rope 79 is pulled out obliquely downward from the sheave member 74a. At this time, the actuation control section 201 of the controller 200 electromagnetically drives the control valve 53 to operate the sub-boom hoisting cylinder 77 based on the oscillating operation signal from the sub-boom oscillating operation lever LV3. Controls rocking motion.

Next, the operator OP performs a winding operation on the winch operation lever LV<b>2 of the upper operation device 45 , and the winch rope 79 is wound by the winch mechanism 75 . At this time, the operation control unit 201 of the controller 200 electromagnetically drives the control valve 53 to operate the winch drive motor 78 based on the winding operation signal from the winch operation lever LV2, thereby causing the winch mechanism 75 to wind. Controls take action. In the winding mode, when the winding operation signal is input from the winch operation lever LV2, the operation control unit 201 operates the operation devices 27, 27, 27 until the extension operation signal is not input from the winch operation lever LV2. Control is performed to stop the operation of the hydraulic actuators 55 other than the sub-boom actuator 56 regardless of the operation signal from 45 . As a result, the boom 30, the workbench 40, and the like do not move during the diagonal pulling work, so it is possible to prevent the vehicle body 2 from becoming unstable and lowering the safety of the work.

In the winding mode, the winch operation restricting section 206 compares the winch load calculated by the winch load calculating section 205 with a preset restricted load. When the winch load calculated by the winch load calculation unit 205 exceeds the limit load, the winch operation restricting unit 206 operates the winch mechanism 75 (winch drive motor 78) regardless of the operation signals from the operation devices 27 and 45. Regulates winding operation. In this embodiment, the regulated load is set to the winch load when the vehicle body 2 does not overturn even if the winch rope 79 is subjected to an obliquely downward outward tensile force due to the winding operation of the winch mechanism 75 . As a result, the winch operation restricting portion 206 restricts the winding operation of the winch mechanism 75 based on the winch load when the vehicle body 2 does not overturn even if the winch rope 79 is subjected to an obliquely downward outward tensile force. As a result, the vehicle body 2 does not become unstable and tip over even when performing diagonal pulling work, and the safety of the work can be improved. Further, the operation of the boom 30 is restricted by the boom operation restricting portion 207 based on the allowable work range in which the vehicle body 2 does not overturn even if the winch rope 79 is subjected to an obliquely downward outward tensile force. Therefore, even when performing diagonal pulling work, the vehicle body 2 does not become unstable and overturn, and the safety of the work can be improved.

When the diagonal pulling work is completed, the operator OP performs a payout operation on the winch operation lever LV2 of the upper operating device 45, pays out the winch rope 79 by the winch mechanism 75, and then attaches the hook 79a to the electric wire (Fig. not shown). At this time, the operation control unit 201 of the controller 200 electromagnetically drives the control valve 53 to operate the winch drive motor 78 based on the extension operation signal from the winch operation lever LV2, thereby extending the winch mechanism 75. to control.

After completing the diagonal pulling work, the operator OP on the workbench 40 operates the upper operating device 45 to switch from the winding mode to the high place mode. In order to switch from the winding mode to the high place mode, first, the operator OP presses the operation stop switch SW1 of the upper operating device 45 to turn off the high place work device (swivel base 20, boom 30, work 40 etc.) is stopped. Next, the operator OP pushes the mode changeover switch SW9 of the upper operating device 45 only once, and then pulls the operation stop switch SW1 to operate the aerial work equipment. Release the suspended state. At this time, the mode switching switch SW9 outputs to the controller 200 a switching operation signal for switching from the winding mode to the high altitude mode. In addition, the winding mode display lamp LP5 (and the temporary support mode display lamp LP6) of the upper operating device 45 are turned off, and the operator OP is notified that the mode has been switched to the high place mode.

As described above, according to the present embodiment, the regulated load at the winch operation regulating portion 206 is obtained by applying an obliquely downward outward tensile force to the winch rope 79 due to the winding operation of the winch mechanism 75 . is set to the winch load when the vehicle body 2 does not overturn. As a result, the winch operation restricting portion 206 restricts the winding operation of the winch mechanism 75 based on the winch load when the vehicle body 2 does not overturn even if the winch rope 79 is subjected to an obliquely downward outward tensile force. As a result, the vehicle body 2 does not become unstable even when the diagonal pulling work is performed, and the safety of the work can be improved.

Further, the boom operation restricting unit 207 restricts the operation of the boom 30 such that the moment calculated by the moment calculating unit 203 exceeds a preset restricted moment when switched to the high altitude mode (non-restricted mode). When switching to the winding mode (restriction mode), the operation of the boom 30 is restricted such that the position of the workbench 40 calculated by the position calculation unit 204 exceeds a preset allowable work range. As a result, when the winch operation restricting unit 206 switches to the winding mode (restriction mode) in which the winding operation of the winch mechanism 75 can be restricted, the boom operation restricting unit 207 performs the operation based on the position of the workbench 40 . Since the operation of the boom 30 is regulated by slanting pulling work, the vehicle body 2 does not become unstable due to the inability to accurately calculate the moment acting on the vehicle body 2, and the safety of the work is improved. becomes possible.

In the present embodiment, the regulated load is the winch load when the vehicle body 2 does not overturn even if the winch rope 79 is subjected to an obliquely downward outward tensile force as an outward tensile force having a horizontal component. is set, but is not limited to this. For example, the regulated load is set to a winch load in which the vehicle body 2 does not overturn even if a horizontal outward tensile force acts on the winch rope 79 as an outward tensile force having a horizontal component. good too.

Therefore, a modified example of the safety device provided in the aerial work vehicle 1 will be described. In this modified example, the regulating load at the winch operation regulating portion 206 is the winch load when the vehicle body 2 does not overturn even if the winch rope 79 is subjected to a horizontal outward tensile force due to the winding operation of the winch mechanism 75. is set to The allowable work range of the boom operation restricting portion 207 is set to the allowable work range in which the vehicle body 2 does not overturn even if a pulling force acting on the winch rope 79 in the horizontal direction outward due to the winding operation of the winch mechanism 75 is applied. be.

Next, with reference to FIG. 8, the control in the case of switching from the high place mode to the winding mode and performing the horizontal pulling work will be described. In this modified example, by switching from the high place mode to the winding mode in the same manner as in the case of the diagonal pulling work, it is possible to perform the horizontal pulling work of the electric wire laid between utility poles. When performing horizontal pulling work in the winding mode, the operator OP on the workbench 40 operates the upper operating device 45 so that the sub-boom 74 is positioned to the side of the electric wire installed between the utility poles. Adjust the position of work platform 40 and sub-boom 74 . At this time, the operation control section 201 of the controller 200 controls the operations of the boom 30, the workbench 40, the sub-boom 74, etc. based on the operation signal from the upper operation device 45, as in the case of the diagonal pulling work.

When the position of the workbench 40 calculated by the position calculation unit 204 reaches the outer edge of the allowable work range, the boom operation control unit 207 outputs operation signals from the operation devices 27 and 45, as in the case of the oblique pulling work. Irrespective of the above, among the operations of the boom 30, the operation in the direction in which the workbench 40 moves outside the allowable work range is restricted. In the winding mode, the operation of the boom 30 is restricted based on the position of the workbench 2 by the boom operation restriction unit 207, so even when performing horizontal pulling work, the moment acting on the vehicle body 2 cannot be accurately calculated. Therefore, the vehicle body 2 does not become unstable, and the safety of work can be improved.

Next, the operator OP swings the sub-boom swing operation lever LV3 of the upper operation device 45 to swing the sub-boom 74 to a vertical position in which the tip side faces vertically upward as shown in FIG. Then, the hook 79a is hooked on an electric wire (not shown) to extend the winch rope 79 horizontally from the sheave member 74a. At this time, the actuation control section 201 of the controller 200 electromagnetically drives the control valve 53 to operate the sub-boom hoisting cylinder 77 based on the oscillating operation signal from the sub-boom oscillating operation lever LV3. Controls rocking motion.

Next, the operator OP performs a winding operation operation on the winch operation lever LV2, and the winch rope 79 is wound by the winch mechanism 75. FIG. At this time, the operation control section 201 of the controller 200 controls the winding operation of the winch mechanism 75 based on the winding operation signal from the winch operation lever LV2, as in the case of the oblique pulling work. As in the case of the oblique pulling work, when the winding operation signal is input from the winch operation lever LV2, the operation control unit 201 does not receive the payout operation signal from the winch operation lever LV2 thereafter. Control is performed to stop the operation of the hydraulic actuators 55 other than the sub-boom actuator 56 regardless of operation signals from the operation devices 27 and 45 . As a result, the boom 30, the workbench 40, and the like do not move during the horizontal pulling work, so it is possible to prevent the vehicle body 2 from becoming unstable and lowering the safety of the work.

As in the case of the diagonal pulling work, the winch operation restricting unit 206 controls the winch load calculating unit 20
5 exceeds the regulation load, the winding operation of the winch mechanism 75 (winch drive motor 78) is regulated regardless of the operation signal from each operation device 27, 45. In this modification, the regulated load is set to the winch load when the vehicle body 2 does not overturn even if a horizontal outward tensile force acts on the winch rope 79 due to the winding operation of the winch mechanism 75 . As a result, the winch operation restricting portion 206 restricts the winding operation of the winch mechanism 75 based on the winch load when the vehicle body 2 does not overturn even if a tensile force acting on the winch rope 79 in the horizontal direction. As a result, the vehicle body 2 does not become unstable and fall over even when performing horizontal pulling work, and the safety of the work can be improved. Further, the operation of the boom 30 is restricted by the boom operation restricting section 207 based on the allowable work range in which the vehicle body 2 does not overturn even if the winch rope 79 is exerted with a tensile force acting on the winch rope 79 in the horizontal direction. Even when the horizontal pulling work is performed, the vehicle body 2 does not become unstable and overturn, and the safety of the work can be improved.

When the horizontal pulling work is completed, the operator OP performs a payout operation on the winch operation lever LV2 of the upper operating device 45, pays out the winch rope 79 by the winch mechanism 75, and then attaches the hook 79a to the wire (Fig. not shown). At this time, the operation control section 201 of the controller 200 controls the extension operation of the winch mechanism 75 based on the extension operation operation signal from the winch operation lever LV2, as in the case of the oblique pulling work. After completing the horizontal pulling work, the operator OP on the workbench 40 operates the upper operating device 45 to switch from the winding mode to the high altitude mode, as in the case of the diagonal pulling work.

According to this modification, the regulated load at the winch operation regulating portion 206 is the amount that the vehicle body 2 does not overturn even if the winch rope 79 is pulled horizontally outward by the winding operation of the winch mechanism 75 . Set to winch load. As a result, the winch operation restricting portion 206 restricts the winding operation of the winch mechanism 75 based on the winch load when the vehicle body 2 does not overturn even if a tensile force acting on the winch rope 79 in the horizontal direction. As a result, the vehicle body 2 does not become unstable even when the horizontal pulling work is performed, and the safety of the work can be improved.

In addition, in this modification, it is also possible to carry out diagonal pulling work of the electric wire constructed between the utility poles. When performing the diagonal pulling work, as described above, the reaction force in the diagonally downward direction from the electric wire acts on the boom 30 via the winch rope 79 . The obliquely downward reaction force from the electric wire acting on the boom 30 is divided into a horizontal component and a vertical component of the reaction force. As a result, part of the reaction force acting on the boom 30 is received by the boom 30 as a compressive force. is smaller when performing oblique pulling work than when performing horizontal pulling work. Therefore, the winch operation restricting portion 206 restricts the winding operation of the winch mechanism 75 on the basis of the winch load when the vehicle body 2 does not overturn even if the winch rope 79 is applied with a tensile force acting on the winch rope 79 in the horizontal direction. Thus, even when performing diagonal pulling work, the vehicle body 2 does not become unstable, and the safety of the work can be improved.

Further, the boom operation restricting unit 207 restricts the operation of the boom 30 such that the moment calculated by the moment calculating unit 203 exceeds a preset restricted moment when switched to the high altitude mode (non-restricted mode). When switching to the winding mode (restriction mode), the operation of the boom 30 is restricted such that the position of the workbench 40 calculated by the position calculation unit 204 exceeds a preset allowable work range. As a result, when the winch operation restricting unit 206 switches to the winding mode (restriction mode) in which the winding operation of the winch mechanism 75 can be restricted, the boom operation restricting unit 207 performs the operation based on the position of the workbench 40 . Since the operation of the boom 30 is regulated by the horizontal pulling work, the vehicle body 2 does not become unstable because the moment acting on the vehicle body 2 cannot be calculated accurately, and the safety of the work is improved. becomes possible. Note that the boom 30 is controlled by the boom operation restricting unit 207 based on the allowable work range in which the vehicle body 2 does not overturn even if the winch rope 79 is subjected to a horizontal outward pulling force due to the winding operation of the winch mechanism 75 . By restricting the operation of , the vehicle body 2 does not become unstable and overturn even when performing diagonal pulling work, and the safety of the work can be improved.

In the above-described embodiment, the sub-boom 74 is pivotally displaced to an oblique position in which the tip side faces obliquely upward when the oblique pulling work is performed. may be oscillatingly displaced. Further, when the horizontal pulling work is performed, the sub-boom 74 is pivotally displaced to the above vertical position, but it is not limited to this, and may be pivotally displaced to the above oblique position.

In the above-described embodiment, the winch load calculation unit 205 calculates the winch load based on the detection information of the hydraulic pressure of the hydraulic oil supplied to the winch drive motor 78 detected by the winch hydraulic pressure detector 255. However, it is not limited to this. For example, the winch load calculator 205 may calculate the winch load based on the tension acting on the winch rope 79 detected using a tension detector (not shown). The winch load calculation unit 205 also calculates the winch load based on the tension acting on the winch rope 79 detected using a tension detector and the ground angle of the winch rope 79 detected using an angle detector (not shown). The horizontal component of the winch load (tensile force in the diagonally downward direction) acting on the winch rope 79 due to the winding operation of the mechanism 75 may be calculated.

In the above-described embodiment, a high altitude mode and a winding mode are provided, but a temporary support mode may also be provided. The temporary support mode is a control mode in which the wires can be temporarily supported using a temporary support device (not shown). In this case, the mode changeover switch SW9 can be pressed to switch from the high altitude mode (non-restricted mode) to the winding mode (restricted mode), the temporary support mode, the high altitude mode, the winding mode, and so on in this order. You may do so.

In the above-described embodiment, the hydraulic pump that supplies the hydraulic oil is driven by the (first) hydraulic pump 51 driven by the engine E of the vehicle body 2 and the power take-off mechanism 52, and by an electric motor (not shown). Although it is configured to be switchable with a second hydraulic pump (not shown), it is not limited to this. For example, only a hydraulic pump driven by the engine E of the vehicle body 2 and the power take-off mechanism 52 may be provided, or only a hydraulic pump driven by an electric motor (not shown) may be provided.

1 aerial work vehicle 2 vehicle body 30 boom 40 workbench 45 upper operation device (SW9 mode changeover switch)
70 lifting device 74 sub-boom (74a sheave member)
75 winch mechanism 78 winch drive motor 79 winch rope 200 controller 203 moment calculation unit 204 position calculation unit 205 winch load calculation unit 206 winch operation regulation unit 207 boom operation regulation unit 251 boom hoisting angle detector 252 boom length detector 253 boom rotation Angle detector 254 Axial force detector 255 Winch oil pressure detector

Claims (3)

A movable vehicle body, a boom provided on the vehicle body so as to be able to move at least up and down, a workbench provided at the tip of the boom, and a sub-boom provided at the tip of the boom so as to be swingable in the vertical direction. and a sheave provided at the tip of the sub-boom, and a winch device for winding and unwinding a rope hung on the sheave, wherein
a winch load detection unit that detects a winch load acting on the winch device through the rope;
a winch operation restricting unit that restricts the winding operation of the winch device when the winch load detected by the winch load detecting unit exceeds a preset restricting load,
The regulating load is set to a winch load in the case where the vehicle body does not overturn even if a pulling force having a horizontal component acts on the rope to the outside due to the winding operation of the winch device. A safety device for aerial work platforms. The regulating load is set to a winch load when the vehicle body does not overturn even if a horizontal outward tensile force acts on the rope due to the winding operation of the winch device. Item 1. A safety device for a vehicle for work at height according to Item 1. When the winch load detected by the winch load detecting section exceeds the regulated load, the winch operation regulating section enters a regulating mode in which the winch operation regulating section regulates the winding operation of the winch device, and the winch operation regulating section enters a non-operating state. a changeover switch operated to switch to and from the non-restricted mode;
a moment detection unit that detects a moment acting on the vehicle body;
a position detection unit that detects the position of the workbench;
When the mode is switched to the non-restricted mode by the operation of the changeover switch, the operation of the boom is restricted such that the moment detected by the moment detection unit exceeds a preset restricted moment, and the changeover switch is operated. a boom operation restricting unit that restricts the operation of the boom such that the position of the workbench detected by the position detecting unit exceeds a preset allowable work range when the mode is switched to the restricting mode by the operation; The safety device for a vehicle for work at height according to claim 1 or 2, characterized by comprising:

Images