JP2000264599A - Safety device for boom type working vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a safety device for boom type working vehicle assuring a high safety without risk that the vehicle body tumbles even in the case the vehicle runs on an up-slope, steps, etc., in the condition that a boom is elongated or allowed to rise or fall to a great extent. SOLUTION: A controller 40 operates a boom by driving actuator valves 51-53 in accordance with the manipulation of a boom operating lever 21 and runs a runner body by driving actuator valves 54a and 54b in compliance with the manipulation of a crawler device actuating lever 23. Sensing is made to judge whether the boom rising/falling angle sensed by a rise/fall angle sensor 31 lies over the reference value set previously or whether the boom length sensed by a length sensor 32 lies over the reference length set previously, and the running of the runner body is prohibited if the inclining angle of the runner body sensed by an inclining angle sensor 34 exceeds the reference value predetermined. Also rise, facing up, and elongation of the boom are prohibited.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to the safety of a boom type work vehicle in which a working device such as a workbench or a crane device is attached to a tip of a boom provided at least on a movable vehicle body so as to be able to move up and down and expand and contract. More specifically, the present invention relates to a safety device for preventing such a work vehicle from overturning.

[0002]

2. Description of the Related Art In general, a boom-type work vehicle is provided with a boom that can move up and down, expand and contract, and swing, on a movable body, and a work device such as a work table for a work vehicle and a crane device is provided at the tip of the boom. Is configured. By moving the working device to a desired position by raising and lowering, expanding and contracting, and turning the boom, it is possible to perform a work according to the purpose.

In such a boom type working vehicle, when the boom is raised and lowered, extended, and the like, the center of gravity of the vehicle body moves toward the tip of the boom, and a moment in the direction of overturning the vehicle body (hereinafter referred to as a overturning moment). Increases. When the overturning moment increases in this way, the vehicle body becomes unstable and the vehicle may overturn. Therefore, a boom working vehicle usually has a restricting device that regulates the operation of the boom before the overturning moment reaches a size that causes the vehicle body to overturn. Is incorporated.

[0004]

However, even when such a regulating device is provided and the boom is raised and lowered or extended within an allowable range, the state in which the boom is extended greatly or the amount of extension is large. The instability of the vehicle body increases when the boom is raised greatly even if it is small. When the vehicle is run in such a state, and the vehicle approaches an up slope or a step, the overturning moment may increase sharply and the vehicle may fall.

The present invention has been made in view of such a problem, and there is a possibility that the vehicle body may fall even when the vehicle travels on an upward slope or a step with the boom raised or extended greatly. It is intended to provide a safety device for a boom-type work vehicle with high safety.

[0006]

In order to achieve the above object, a safety device for a boom type working vehicle according to a first aspect of the present invention includes a movable body (for example, a traveling body 11 in the embodiment), A boom-type work vehicle including at least a boom provided on a vehicle body so as to be able to move up and down and telescopically and a work device (for example, a work table 15 in the embodiment) attached to a tip end of the boom. Angle detecting means (for example, the angle detector 31 in the embodiment) for detecting the angle of undulation, and length detecting means (for example, the length detector 3 in the embodiment) for detecting the length of the boom.
2) and inclination angle detecting means for detecting an inclination angle of the vehicle body in the front-rear direction (for example, the inclination angle detector 3 in the embodiment)
4) the boom undulation angle detected by the undulation angle detection means is greater than a preset reference undulation angle, or the boom length detected by the length detection means is set to a predetermined reference length. Traveling restricting means for prohibiting traveling of the vehicle body when it is detected that the vehicle body exceeds the predetermined inclination angle, and when it is detected that the inclination angle of the vehicle body detected by the inclination angle detecting means exceeds a predetermined reference inclination angle (for example, , The controller 40 in the embodiment).

[0007] According to the safety device having such a configuration, the vehicle body travels in a state where the boom undulation angle exceeds the reference undulation angle or the boom length exceeds the reference length, and the vehicle body tilts. When the angle becomes larger than the reference inclination angle, the traveling of the vehicle body is prohibited. Therefore, even when the vehicle is running on an upward slope or a step with the boom largely raised or extended, there is no possibility that the vehicle body will fall over, and work can be performed safely.

A safety device for a boom type working vehicle according to a second aspect of the present invention includes a vehicle body capable of running, a boom provided at least on the vehicle body so as to be able to move up and down, and a telescopic operation. In a boom type work vehicle configured to include a device, an up-and-down angle detection unit that detects an up-down angle of the boom, a length detection unit that detects a length of the boom, and a tilt angle of a vehicle body in a front-rear direction is detected. The tilt angle of the vehicle body detected by the tilt angle detecting means corresponds to the combination of the boom angle detected by the hoist angle detecting means and the boom length detected by the length detecting means. Traveling restriction means for prohibiting traveling of the vehicle body when it is detected that the reference inclination angle exceeds a reference inclination angle determined in advance.

According to the safety device having such a configuration, when the inclination angle of the vehicle body exceeds the reference inclination angle determined in accordance with the combination of the boom angle and the length of the boom at that time, the vehicle travels. Is forbidden. Therefore, as in the case of the safety device according to the first aspect of the present invention, there is no possibility that the vehicle body will fall even when the vehicle travels on an upward slope or a step with the boom raised or extended greatly.

In the above two safety devices, boom operation restricting means (for example, the controller 40 in the embodiment) for prohibiting raising and extending operation of the boom when traveling of the vehicle body is prohibited by the driving restricting means. It is preferable to have With this configuration, it is possible to prevent the danger that the vehicle body will become more unstable due to erroneous boom operation from the travel-restricted state. In addition, when such a restriction is performed, the first safety device causes the boom to fall down so that the boom undulation angle is smaller than the reference undulation angle, and the boom is contracted to make the boom length smaller than the reference length. The above restriction can be released by shortening the length of the vehicle. In the second safety device, the regulation can be released by lowering the boom or contracting the boom so that the newly set reference tilt angle is larger than the current running body tilt angle. . This eliminates the need for a special operation for canceling the regulation, and eliminates the possibility of accidentally canceling the regulation (running regulation and boom operation regulation) in an unsafe state, thereby achieving higher safety. Can be

In the safety device according to the first aspect of the present invention,
In the case where the above-described regulation is applied, it is preferable that the contraction of the boom is prohibited when the up-and-down angle of the boom at that time is equal to or larger than the reference up-and-down angle, and that the boom is only allowed to fall down. This is to avoid the danger that the rearward movement of the center of gravity due to the contraction of the boom will cause the traveling body to fall backward, and if the length of the boom is less than the reference length, the boom undulation angle will be less than the reference undulation angle. Lower the boom until the boom is tilted, and if the length of the boom is longer than the reference length, first lower the boom until the boom hoisting angle is less than or equal to the reference hoisting angle. After the degree is increased, the boom is contracted to release the regulation. Thereby, the safety against the vehicle body overturn can be further enhanced.

[0012]

Preferred embodiments of the present invention will be described below with reference to the drawings. FIG. 2 shows a self-propelled aerial work vehicle (hereinafter, referred to as a work vehicle) 10 provided with a boom-type work vehicle safety device according to the first invention. The work vehicle 10 is provided with a swivel 13 on the upper part of a traveling body 11 having a pair of right and left crawler devices 12, 12. Mounted up and down freely. At the tip of the boom 14, a worktable 15 for boarding the worker is mounted so as to be horizontally swingable with respect to the tip of the boom 14.

Each of the left and right crawler devices 12, 12
A starting wheel 12a, which is driven to rotate by receiving a supply of pressure oil from a hydraulic pump (not shown) built in the swivel 13, a floating wheel 12b, which can rotate freely, and both wheels 12a, 1
2c crawler belt 12c
And is configured.

The swivel base 13 is driven by hydraulically driving a swivel motor 16 incorporated in the swivel base 13 itself, so that the traveling body 11 is driven.
Can be turned horizontally with respect to. The boom 14 has a base boom 14a and an intermediate boom 14b.
The tip boom 14c is of a telescoping type, and can be expanded and contracted by hydraulically driving a telescopic cylinder 17 built in the boom 14.
Further, the boom 14 has a base end boom 14 a pivotally connected to a boom support member 18 formed on the upper part of the swivel 13.
By hydraulically driving an up / down cylinder 19 provided over both the swivel base 13 and the base end boom 14a, the up / down cylinder 19 can be raised / lowered with respect to the traveling body 11. The undulating cylinder 19, the telescopic cylinder 17, and the turning motor 16 are connected to the starting wheel 12 of the crawler device 12 described above.
Similar to a, it operates by receiving the hydraulic pressure supplied from the hydraulic pump.

A vertical post (not shown), which is configured to be always vertical, is attached to the tip of the boom 14, and the work table 15 is attached to the vertical post. Therefore, the worktable 15 is always kept horizontal regardless of the posture of the boom 14. The worktable 15 includes an electric swing motor 20 provided inside the worktable 15.
, The head can be swung horizontally with respect to the vertical post.

As shown in FIG. 3, the work table 15 is provided with a boom operating lever 21, a swinging operating lever 22, and a crawler device operating lever 23. The crawler device operating lever 23 includes left and right crawler devices. It comprises levers 23a and 23b corresponding to 12 and 12, respectively. The boom operation lever 21 is capable of performing a tilting operation in all directions of 360 degrees including front, rear, left and right and a twisting operation around the axis from the neutral position, and the swinging operation lever 22 and the left and right crawler device operation levers 23a, 23b Any of them can be tilted forward or backward from the neutral position. Each of these levers is manually operated, but is configured to automatically return to the neutral position when the hand is released from the tilted or twisted state.

At the base of the boom operating lever 21, the tilting state of the lever 21 in the front-rear direction (tilting direction and tilt amount)
Are provided, a potentiometer for detecting a tilt state (tilt direction and tilt amount) in the left and right direction, and a potentiometer for detecting a twist state (twist direction and twist amount). The information detected by each potentiometer is output as a command signal for operating the up-and-down cylinder 19, a command signal for operating the telescopic cylinder 17, and a command signal for operating the swing motor 16, respectively.

The swing operation lever 22 is a swing motor 20.
The switch is turned off when the lever 22 is at the neutral position, and turned on when the lever 22 is tilted forward or backward. When the swing operation lever 22 is tilted forward, the swing motor 20 rotates in the forward direction and the work table 15 is rotated.
When the vertical post rotates counterclockwise and the swing operation lever 22 is tilted backward, the swing motor 20 rotates in the reverse direction, and the worktable 15 rotates clockwise to the vertical post.

Left and right crawler device operating levers 23a, 2
3b, these levers 23a, 23
Potentiometers for detecting the tilt state (tilt direction and tilt amount) in the front-back direction of b are provided, and information detected by each potentiometer is output as a command signal for operating the left and right crawler devices 12, 12, respectively. .

An elevation angle detector 31 and a length detector 32 are provided at the base end and the tip end of the boom 14, respectively. The elevation angle and the length of the boom 14 are detected by the detectors 31 and 32, respectively. It has become so. A turning angle detector 33 is provided near the turning motor 16, and the turning angle of the turntable 13, that is, the turning angle of the boom 14 is detected by the detector 33. Further, the traveling body 11 has an inclination angle detector 34 (FIG. 2).
(Not shown in the figure) is provided.
1 is to be detected.

FIG. 1 is a block diagram showing a configuration of a control system including a safety device according to the present invention. As shown in this figure, the command signal output by operating the boom operation lever 21 and the left and right crawler device operation levers 23a, 23b
Is output to the controller 40. In addition, the undulation angle detector 31, the length detector 3
2. The detection information from the turning angle detector 33 and the detection information from the inclination angle detector 34 are also input to the controller 40.

The up / down cylinder operating valve 51 and the telescopic cylinder operating valve 5 for controlling the supply of hydraulic pressure to the up / down cylinder 19, the telescopic cylinder 17 and the turning motor 16 to operate them.
2 and the swing motor operating valve 53 are electromagnetically driven based on a control signal output from the controller 40. Further, the left and right crawler device operating valves 54a, 54b for controlling the supply of the hydraulic pressure to the left and right crawler devices 12, 12 to operate them are also driven by the control signal output from the controller 40 in electromagnetic proportional driving. I have.

In the work vehicle 10 having such a configuration, when an operator on the work table 15 tilts or twists the boom operation lever 21, a command signal corresponding to the operation is input to the controller 40. The CPU 41 of the controller 40 includes information on the operation direction (tilt or torsion direction) and the operation amount (tilt or torsion amount) of the boom operation lever 21 included in the input command signal, the undulation angle detector 31, and the length detection. Based on the detection information from the device 32 and the turning angle detector 33, arithmetic processing is performed, and a control signal is output to drive each of the operating valves 51 to 53. Thereby, the boom 14 moves up and down, expands and contracts, and turns according to the operation of the boom operation lever 21.

As described above, in the work vehicle 10, the boom 14 can be raised, contracted, and turned by operating the boom operation lever 21, and the swinging operation lever 22 can be operated by operating the work table as described above. 15 can be swung around the vertical post, so that
The operator who boarded the No. 5 operated the lever 1 by operating his own lever.
5 can be moved to a desired position and adjusted in a desired direction to perform work at a high place.

When the worker on the work table 15 tilts the left and right crawler device operating levers 23a and 23b, a command signal corresponding to the operation is input to the controller 40. The CPU 41 of the controller 40 performs arithmetic processing based on information on the operation direction (tilt direction) and the operation amount (tilt amount) of the left and right crawler device operation levers 23a and 23b included in the input command signal, and outputs a control signal. The output is used to drive the left and right crawler device operation valves 54a and 54b. As a result, the left and right crawler devices 12, 12 rotate in the forward or backward direction in accordance with the operation of the crawler device operation levers 23a, 23b.

The left and right crawler devices 12, 12 can be operated independently in desired directions in the forward and reverse directions. By operating the right and left crawlers simultaneously in the same direction, the traveling body 11 moves forward or backward. It is possible. In addition, the traveling body 11 can be turned by operating only one of the left and right sides or the left and right directions. Note that the former is a turn (pivot turn) with the crawler device 12 on the non-operating side as a fulcrum, and the latter is a turn (spin turn) on the spot.

The storage unit 42 of the controller 40 previously stores three values of a reference undulation angle αo, a reference length Lo, and a reference inclination angle θo. Here, the reference hoisting angle αo is a value arbitrarily determined for the hoisting angle of the boom 14, and the reference length Lo is a value arbitrarily determined for the length of the boom 14. The reference tilt angle θo is the boom 1
4 has a hoisting angle αo, a length of the boom 14 is Lo, and the load applied to the worktable 15 is maximum,
Is determined by multiplying a tilt angle (limit tilt angle) obtained as a limit tilt angle leading to a fall by a predetermined coefficient (<1).

The CPU 41 of the controller 40 always detects the up / down angle of the boom 14 detected by the up / down angle detector 31, the length of the boom 14 detected by the length detector 32, and the tilt angle detector 34. Running body 1
The values α, L, and θ of the tilt angle of 1 are taken in, and these values α, L, and θ are compared with the above three values αo, Lo, and θo to determine the magnitude relation of each. Then, it is detected that the detected boom hoisting angle α exceeds the reference hoisting angle αo, or that the detected boom length L exceeds the reference length Lo, and the detected traveling body tilt angle θ Is greater than the reference inclination angle θo, the crawler device operation levers 22a, 22
A control signal for holding the crawler device operating valves 54a and 54b at the neutral position regardless of whether or not the command signal is output from the control signal 2b to prohibit the traveling of the traveling body 11 and the command signal or the boom for causing the boom 14 to fall down Except when a command signal for contracting the boom 14 is output, a control signal for holding the up-and-down cylinder operating valve 51 and the telescopic cylinder operating valve 52 at the neutral position is output to raise and extend the boom 14 (i.e., The operation of the boom 14, which makes the boom 14 more unstable, is prohibited.

As described above, according to the safety device according to the first aspect of the present invention, the vehicle travels in a state where the boom hoisting angle α exceeds the reference hoisting angle αo or the boom length L exceeds the reference length Lo. When the body 11 travels and the traveling body inclination angle θ becomes larger than the reference inclination angle θo, traveling of the traveling body 11 is prohibited. Therefore, even when the vehicle is running on an inclined surface, a step, or the like with the boom 14 largely raised or extended, there is no possibility that the traveling body 11 falls over, and the work can be performed safely. The traveling body 11
When the traveling of the vehicle is prohibited, the raising and extension operations of the boom 14 are also prohibited. Therefore, the traveling body 11 performs an erroneous boom operation from the traveling-restricted state to make the work vehicle 10 more unstable. It is possible to prevent the danger of being lost.

As described above, the traveling of the traveling body 11 is prohibited,
In a state in which the raising and extending of the boom 14 is prohibited, the boom 14 is caused to fall down so that the boom raising and lowering angle α is smaller than the reference raising and lowering angle αo, and the boom 14 is contracted to set the boom length L to the reference length. By making the length shorter than Lo, the regulation can be released. For this reason, a special operation for canceling the regulation is not required, and there is no possibility that the regulation (running regulation and boom operation regulation) is canceled in an unsafe state, and higher safety is obtained.

In the case where the above-mentioned restriction is activated, the contraction of the boom 14 is also prohibited when the boom raising / lowering angle α at that time is equal to or larger than the reference raising / lowering angle αo, and the restriction is made that only the boom 14 can fall down. Is preferred.
This is to avoid the danger that the rearward movement of the center of gravity due to the contraction of the boom 14 causes the traveling body 11 to fall backward, and if the boom length L is equal to or less than the reference length Lo, the boom hoisting angle α is equal to or smaller than the reference length Lo. The boom 14 is tilted down until the boom angle becomes equal to or less than αo, and the above-described standard is released. If the boom length L exceeds the reference length Lo, first, the boom is adjusted until the boom hoist angle α becomes equal to or less than the standard wobble angle αo. The boom 14 is contracted by retracting the boom 14 and temporarily increasing the degree of safety against falling backward, thereby releasing the restriction. Thereby, the safety against the vehicle body overturn can be further enhanced. FIG. 4 is a diagram showing an operation restriction range of the boom 14 in a state where the above-described restriction is applied. An area R1 (an area indicated by oblique lines) indicates an area in which raising and extension of the boom 14 is prohibited, and an area R2 (a horizontal line). The area indicated by is the boom 1
4 shows an area where raising, extension and contraction are prohibited.

In this embodiment, the reference inclination angle θ
The value of o is for the case where the load applied to the work table 15 is the maximum. However, a load detector capable of detecting the load applied to the work table 15 is provided, and an optimal reference value is set according to the detection result from the load detector. A configuration in which the inclination angle θo is set may be adopted. In this case, the reference undulation angle αo and the reference length L
The data of the reference inclination angle θo set according to o is stored in the storage unit 42 of the controller 40 in advance in the form of a correspondence table for each load W. If you do this,
Even if the reference undulation angle αo and the reference length Lo are the same, the smaller the applied load W, the larger the reference inclination angle θo can be. Therefore, the applied load is fixed at the maximum and the reference inclination angle θo is set. It is possible to extend the working range as compared with the specified case. The reference tilt angle θo corresponding to the load W in this case is such that the running body 11 falls down when the boom angle is αo, the length of the boom 14 is Lo, and the load on the worktable 15 is W. It is determined by multiplying a tilt angle (limit tilt angle) obtained as a limit tilt angle by a predetermined coefficient (<1).

Next, a safety device according to the second invention will be described. This safety device differs only in the processing of the controller 40 in the above-described safety device according to the first invention. Therefore, only the controller 40 will be described here, and the description of the other components will be omitted.

In the storage unit 42 of the controller 40 in the safety device according to the second invention, the reference inclination angle θo determined corresponding to various combinations of the elevation angle α1 of the boom 14 and the length L1 of the boom 14 is stored. Are stored in advance in the form of a correspondence table. Here, each reference inclination angle θo
Is the inclination angle (limit inclination) obtained as the limit inclination angle at which the traveling body 11 falls down when the boom 14 has an elevation angle α1, the length of the boom 14 is L1, and the load applied to the worktable 15 is the maximum. Angle) with a predetermined coefficient (<1)
Multiplied by

The CPU 41 of the controller 40 always shows the combination of both the values α and L of the boom 14 detected by the up / down angle detector 31 and the length of the boom 14 detected by the length detector 32 in a correspondence table. The reference inclination angle θo is determined in correspondence with the combination of α1 and L1, and the value θ of the inclination angle of the traveling body 11 detected by the inclination angle detector 34 is compared with the reference inclination angle θo to determine the magnitude relation. I'm asking. When it is detected that the detected traveling body inclination angle θ is greater than the reference inclination angle θo, the crawler device operation valves 54a, 54b regardless of whether or not the command signal is output from the crawler device operation levers 22a, 22b. A control signal for holding the vehicle in the neutral position is output to prohibit the traveling of the traveling
Except when a command signal for causing the boom 14 to contract or a command signal for causing the boom 14 to contract is output.
1 and a control signal for holding the telescopic cylinder operating valve 52 at the neutral position is output to raise and extend the boom 14 (ie, the operation of the boom 14 that makes the work vehicle 10 more unstable).
Ban.

As described above, according to the safety device according to the second aspect of the present invention, the traveling body inclination angle θ is determined in accordance with the combination of the boom up / down angle α and the boom length L at that time. Is exceeded, the traveling of the traveling body 11 is prohibited. For this reason, as in the case of the safety device according to the first aspect of the present invention, even when the boom 14 travels on a rising slope or a step with the boom 14 largely raised or extended, the traveling body 11 may fall. There is no. The traveling body 11
When the traveling of the vehicle is prohibited, the raising and extension operations of the boom 14 are also prohibited, so that the traveling body 11 performs an erroneous boom operation from the state in which the traveling is restricted to make the work vehicle 10 more unstable. It is possible to prevent the danger of being lost.

As described above, the traveling of the traveling body 11 is prohibited,
And in the state where raising and extension of the boom 14 are prohibited, the boom 14 is lowered or the boom 14 is contracted, and the reference inclination angle θo newly set thereby is made smaller than the current traveling body inclination angle θ. By increasing the size, the travel regulation of the traveling body 11 and the operation regulation of the boom 14 can be released. Therefore, as in the case of the safety device according to the first aspect of the present invention, a special operation for releasing the restriction is not required, and the restriction (running restriction and boom operation restriction) is released in an unsafe state. There is no danger.

Also in this embodiment, the work table 1
5 is provided with a load detector capable of detecting a load, and an optimum reference inclination angle θo is determined according to a detection result from the load detector.
May be set. In this case, the reference tilt angle θo is determined according to a combination including the detected boom undulation angle α and the boom length L, as well as the load W of the work table 15 detected by the load detector. Become. As a result, the working range can be expanded as compared with the case where the applied load is fixed at the maximum and the reference inclination angle θo is determined. It should be noted that each reference inclination angle θo is an inclination angle (limit inclination angle) obtained as a limit inclination angle at which the traveling body 11 falls down when the boom undulation angle α, the boom length L, and the workbench load load W are the same. ) Is multiplied by a predetermined coefficient (<1).

Although the embodiment of the safety device for the boom type working vehicle according to the present invention has been described above, the present invention is not limited to the above-described embodiment, and various modifications are possible. For example, in the above-described embodiment (both the first and second embodiments), the turning angle of the boom 14 is not considered, but the reference tilt angle θo is set according to the turning position of the boom 14.
Is different from the optimum value, the reference inclination angle θo considering the turning angle of the boom 14 is set, and the controller 40 performs an arithmetic process including the detection information output from the turning angle detector 33, and It is preferable to stop the running of the vehicle 11 and regulate the operation of the boom 14. By doing so, it is possible to further expand the working range.

In the above embodiment, a self-propelled aerial work vehicle has been described by way of example. However, a driving body is provided with a driver seat, and the driving body is driven from this driver seat. It may be an aerial work vehicle. Further, the working device at the tip of the boom 14 may be a crane device (sheave) or the like instead of the working table 15. Furthermore, the traveling device of the traveling body 11 does not have to be the crawler device 12, and may be tire wheels.

[0041]

As described above, according to the safety device for a boom type working vehicle according to the first aspect of the present invention, the boom angle is greater than the reference angle, or the boom length is equal to the reference length. Run the car body in a state where it exceeds
When the inclination angle of the vehicle body becomes larger than the reference inclination angle, traveling of the vehicle body is prohibited. Therefore, even when the vehicle is running on an upward slope or a step with the boom largely raised or extended, there is no possibility that the vehicle body will fall over, and work can be performed safely.

According to the safety device for a boom type working vehicle according to the second aspect of the present invention, the inclination angle of the vehicle body is determined by the reference inclination angle determined according to the combination of the boom angle and the length at that time. If the vehicle speed exceeds the threshold, the running of the vehicle body is prohibited. Therefore, as in the case of the safety device according to the first aspect of the present invention, there is no possibility that the vehicle body will fall even when the vehicle travels on an upward slope or a step with the boom raised or extended greatly.

It is preferable that the two safety devices have a boom operation restricting means for prohibiting the boom raising and extending operation when the traveling of the vehicle body is prohibited by the traveling restricting means. With this configuration, it is possible to prevent the danger that the vehicle body will become more unstable due to erroneous boom operation from the travel-restricted state. In addition, when such a restriction is performed, the first safety device causes the boom to fall down so that the boom undulation angle is smaller than the reference undulation angle, and the boom is contracted to make the boom length smaller than the reference length. The above restriction can be released by shortening the length of the vehicle. In the second safety device, the regulation can be released by lowering the boom or contracting the boom so that the newly set reference tilt angle is larger than the current running body tilt angle. . This eliminates the need for a special operation for canceling the regulation, and eliminates the possibility of accidentally canceling the regulation (running regulation and boom operation regulation) in an unsafe state, thereby achieving higher safety. Can be

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of a control system including a safety device for a boom type work vehicle according to the present invention.

FIG. 2 is a side view of a self-propelled aerial work vehicle equipped with the safety device.

FIG. 3 is a perspective view of a work table of the self-propelled aerial work vehicle.

FIG. 4 is a diagram showing an operation restriction range of a boom of the aerial work vehicle in a state where travel restriction is applied.

[Explanation of symbols]

Reference Signs List 1 self-propelled aerial work vehicle (boom-type work vehicle) 11 traveling body (vehicle body) 14 boom 15 workbench (working device) 31 undulation angle detector (undulation angle detection means) 32 length detector (length detection means) 34) Tilt angle detector (tilt angle detecting means) 40 Controller (running restricting means, boom operation restricting means)

Claims (3)

[Claims] 1. A boom-type working vehicle comprising: a movable vehicle body; a boom provided at least on the vehicle body so as to be able to move up and down, and a working device attached to a tip end of the boom. The safety device according to any one of claims 1 to 3, wherein an up-and-down angle detection unit that detects an up-down angle of the boom, a length detection unit that detects a length of the boom, and an inclination angle detection unit that detects an inclination angle of the vehicle body in a front-back direction The boom undulation angle detected by the undulation angle detection means is greater than a preset reference undulation angle, or the boom length detected by the length detection means is a preset reference length. Is detected, and it is detected that the inclination angle of the vehicle body detected by the inclination angle detecting means exceeds a predetermined reference inclination angle. And a travel restricting means for prohibiting travel of the vehicle body. 2. A boom-type work vehicle comprising: a movable vehicle body; a boom provided at least on the vehicle body so as to be able to move up and down, and a work device attached to a tip end of the boom. The safety device according to any one of claims 1 to 3, wherein an up-and-down angle detection unit that detects an up-down angle of the boom, a length detection unit that detects a length of the boom, and an inclination angle detection unit that detects an inclination angle of the vehicle body in a front-rear direction. And the inclination angle of the vehicle body detected by the inclination angle detection means corresponds to a combination of the boom undulation angle detected by the undulation angle detection means and the boom length detected by the length detection means. And a travel restricting means for prohibiting the travel of the vehicle body when it detects that the vehicle body exceeds a reference inclination angle determined as above. Place. 3. The vehicle according to claim 1, further comprising a boom operation restricting unit that prohibits raising and extending the boom when the traveling of the vehicle body is prohibited by the traveling restricting unit. A safety device for a boom-type work vehicle according to the description.