JPH08268694A - Safety device for outrigger - Google Patents

Abstract

PURPOSE: To provide a safety device for an outrigger which can improve safety of a system having the outrigger. CONSTITUTION: By an extending/contracting amount detecting means 100, an amount of extending/contracting an outrigger beam 11 is detected, and by a work operating detecting means, whether the outrigger beam 11 perform extending/contracting work operation or not or stops or not is detected. When stopping extending/contracting work operation of the outrigger beam 11 is detected by the work operation detecting means, a detection value detected by the extending/contracting amount detecting means is stored as a memory value in a detection value memory means, to compare the detection value with the memory value in a condition of not performing the extending/contracting work operation of the outrigger beam 11 in the detection value memory means, and when a difference of this comparison exceeds a prescribed range to change, an alarm signal is output from a comparator, to perform alarm action by an alarm means.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a safety device for an outrigger, which is constructed so that it can be laterally extended to support a vehicle body.

[0002]

2. Description of the Related Art For example, the front, rear, left and right sides of a work vehicle having a boom capable of undulating, turning, etc., such as an aerial work vehicle or a crane vehicle, are used to stably support the vehicle body during work. A jack device is installed. As this jack device, there is an outrigger (outrigger jack device) that includes an outrigger beam that is inserted to extend and contract toward the side of the vehicle body and a jack that is attached to the tip of this outrigger beam. This outrigger extends the outrigger beam, and then grounds the jack to protect the vehicle body against the moment (hereinafter referred to as the overturning moment) that acts in the direction of tipping over the vehicle body based on the boom's own weight and tip load. It can be stably supported.

The overturning moment acting on the vehicle body changes depending on the boom operating range such as the hoisting angle of the boom and the amount of expansion and contraction of the boom. It will change depending on. For this reason, in an aerial work vehicle having the above-mentioned outrigger, boom operating range restricting means for restricting the boom operating range depending on the extension amount of the outrigger beam may be provided.

In order to properly regulate the boom operating range, it is necessary to accurately detect the extension amount of the outrigger beam. As a detection device for detecting the extension amount of the outrigger beam, the extension amount of the outrigger beam is detected by a potentiometer. There is one that is designed to detect. In the detection device having such a configuration, it is necessary to provide a safety device of the detection device in order to prevent improper boom operating range regulation due to a malfunction of the detection device. As such a safety device, for example, when the detection signal from the potentiometer cannot be sent (broken wire), or the detection signal of a certain value or more is still output (short circuit), an alarm signal is sent to the operator. BACKGROUND ART There have been conventionally known things that call attention and regulate the operation of a boom.

[0005]

However, in the safety device as described above, the alarm signal is not transmitted in the case of a failure other than the disconnection or short circuit of the potentiometer, and the safety of the system having the outrigger is insufficient. There is a problem.

The present invention has been made in view of the above problems, and an object of the present invention is to provide an outrigger safety device capable of improving the safety of a system having an outrigger.

[0007]

In order to achieve the above object, the outrigger safety device of the present invention is arranged so that it can be expanded and contracted toward the side of the vehicle body by the expansion and contraction amount detecting means, and its lower end is The amount of expansion and contraction of the outrigger that grounds and supports the vehicle body to the side of the vehicle body is detected, and the operation operation detection means detects whether the outrigger operation is performed or is stopped.

The detection value detected by the expansion / contraction amount detecting means is stored as a stored value in the detection value storage means when the operation operation detecting means detects that the expansion / contraction operation of the outrigger is stopped, and the outrigger expansion / contraction is expanded. The comparator compares the stored value and the detected value in the state where the operation is not performed, and outputs an alarm signal from the comparator when the difference changes beyond the value in the preset range. The alarm means, which has received the alarm signal, activates the alarm.

[0009]

In the outrigger safety device constructed as described above, a detection value exceeding a preset range is detected due to an abnormality in the expansion / contraction amount detecting means while the outrigger expansion / contraction operation is not performed. Alarm buzzer,
An alarm is activated by an alarm lamp.

As the expansion / contraction amount detecting means, the amount of extension of the outrigger is detected by detecting the amount of rotation of the reel rotated by the extension of the outrigger and the pulling of the cable (the amount of extension of the cable) with the potentiometer. When using, as an abnormal mode of the expansion and contraction amount detection means,
In addition to the disconnection and short circuit of the potentiometer provided in the detection means, there is an abnormality in the connecting member that connects the outrigger and the potentiometer in order to operate the potentiometer as the outrigger expands and contracts.

Further, when a work device such as a boom is provided on the vehicle body, the work device is operated (the boom falls and falls).
The alarm may be issued by stopping the extension operation).

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT A preferred embodiment of the present invention will be described below with reference to the drawings. First, an aerial work vehicle equipped with an outrigger safety device according to the present invention will be described with reference to FIG. The aerial work vehicle 1 is provided with a boom 2 rotatably at a rear portion of a vehicle body 4, and the boom 2 is telescopically (nestedly) telescopically supported while being vertically supported on the vehicle body 4. It is configured. A workbench 3 is attached to the tip of the boom 2, and the workbench 3
An operator boarding the vehicle can move to an arbitrary height by controlling the operation of each operation of the boom 2.

In order to move the workbench 3 to a high place by performing the hoisting and extending / contracting operations of the boom 2 in such a manner that the vehicle body 4 can be stably operated, the vehicle body 4 is provided at four positions in front, rear, left and right. Is equipped with an outrigger (in FIG. 2,
Outriggers 10, 20 arranged on the left side of the vehicle body 4
Only represented). This outrigger is configured to be able to extend and contract toward the side of the vehicle body 4, and the larger the amount of extension (the wider the width of the outrigger), the more stable the vehicle body 4 can be supported, and the range of movement of the workbench 3 (boom 2). The operating range of) becomes wider.

Here, the configuration of the outrigger will be described by taking the left rear outrigger 10 arranged on the left rear side of the vehicle body 4 as an example in addition to FIG. The outrigger 10 is the vehicle body 4
The outrigger beam 11 is inserted into the outrigger box 4a attached to the side of the vehicle body 4 so that the outrigger beam 11 can extend and contract toward the side of the vehicle body 4, and the jack 13 is attached to the tip of the outrigger beam 11.
Is attached. The jack 13 is composed of an outer post 13a and an inner post 13b that is inserted into the outer post 13a so as to extend and contract downward.

When the boom 2 is raised and lowered and extended and retracted in order to move the workbench 3 to a desired height, the outrigger beam 11 is extended toward the side of the vehicle body 4 and the inner post 13b is fixed. The body 13 is stably supported by extending the jack 13 downward until it receives the ground reaction force.

Here, depending on the extension amount of the outrigger beam 11 and the operating state (raising angle, extension amount) of the boom 2, the overturning moment generated due to the weight of the boom 2 and the weight of the workbench 3 becomes excessive. The outrigger may not support the vehicle body 4 stably.

Therefore, as shown in FIG. 3, the aerial work vehicle 1 is provided with boom operation restricting means 90.
The boom operation restricting means 90 is controlled by the boom operation range calculator 73 provided in the controller 70 based on the extension amount of each outrigger beam detected by the extension amount detectors 100 to 400 provided in each outrigger. A range (operating range) that allows the boom 2 to operate without causing the work vehicle 1 to become unstable is calculated, and an operating operation of the boom 2 from a boom operating device (not shown) that exceeds the calculated operating range is performed. When performed, the operation of the boom 2 is regulated regardless of the operation signal from the boom operation device.

In the aerial work vehicle 1 configured as described above, since the operating range of the boom 2 is calculated based on the extension amount of each outrigger beam, the extension amount of each outrigger beam needs to be accurately detected. There is. For this reason, in the aerial work vehicle 1, the following outrigger beam extension amount detector (expansion / contraction amount detecting means) is provided to detect the extension amount of the outrigger beam.

Here, the extension amount detector 100 for detecting the extension amount of the outrigger beam 11 of the outrigger 10 will be described as an example of the extension amount detector. In the extension amount detector 100, a reel 110 rotatably arranged with respect to the vehicle body 4, a cable 120 wound around the reel 110, and a contact portion connected to a rotation shaft hit the outer circumference of the reel 110. It is composed of a potentiometer 140 that detects the amount of rotation of the reel 110 by coming into contact with it.

The tip of the cable 120 is connected to a cable holding member 130 attached to the outrigger beam 11. Also, the reel 110 is always the cable 12
It is configured to have a biasing force in the direction of winding 0. Therefore, when the outrigger beam 11 expands and contracts with respect to the vehicle body 4, the reel 110 rotates while maintaining the pulled state of the cable 120. The rotation amount (rotation angle) of the reel 110 is detected by the potentiometer 140, and the extension amount of the outrigger beam 11 with respect to the vehicle body 4 is detected based on the detected value.

In the aerial work vehicle 1, the extension amount detector 1
Extension detectors 200, 300, 40 having the same configuration as 00
0 is also provided for each outrigger. As a result, the extension amount of each outrigger beam can be detected, and the boom operation range is calculated based on these detected values.

Here, if the potentiometer 140 or the like in each of the extension amount detectors 100 to 400 is defective, the extension amount cannot be accurately detected, and an appropriate boom operating range can be calculated. Disappear. For this reason, the aerial work vehicle 1 is provided with an outrigger safety device, and when an accurate extension amount cannot be detected, an alarm is activated to alert the operator.

The outrigger safety device detects whether or not each of the extension amount detectors (expansion / contraction amount detecting means) 100 to 400 and an outrigger operating device (not shown) for extending / contracting the outrigger beam are operated. Outrigger operation detector (operation operation detection means) 50 and controller 70
The expansion amount storage device (detection value storage means) 71, the comparator 72, and the alarm device 80, which are provided in FIG.

The extension amount storage 71 is used for each extension amount detector 1 when the outrigger operation detector 50 detects that the extension / contraction operation of the outrigger beam is not performed.
The detection value detected by 00 to 400 is stored. The comparator 72, in a state where the outrigger operation detector 50 detects that the expansion / contraction operation of the outrigger beam is not performed, the stored values stored by the expansion amount storage 71 and the expansion amount detector 100. .. to 400, the respective detected values are compared, and when the difference between the stored value and the detected value exceeds a preset range, the comparator 72 sends an alarm signal.

The alarm device 80 is composed of an alarm buzzer and an alarm lamp. When the alarm signal from the comparator 72 is received, the alarm buzzer sounds and the lamp is turned on to alert the operator. The comparator 72
The buzzer may be sounded with a different tone color not only when the alarm signal is received from, but also when the boom 2 operates beyond the operation range of the boom 2 calculated by the boom operation range calculator 73.

Now, the alarm operation by the safety device of the outrigger configured as described above will be described. For example, it is assumed that the voltage (detection value) detected between the fully retracted position and the fully extended position of the outrigger beam is 5V to 10V when the potentiometer 140 has no abnormality. Then, the outrigger operation device is operated to extend the outrigger beam from the fully retracted position, and the extension operation is stopped when the detected value reaches 8V. The detected value at this time (8
V) is stored in the expansion amount storage unit 71 as a stored value.

Here, if the potentiometer 140 is abnormal even though the outrigger operating device is not operated, the detected value fluctuates from 8V. The comparator 72 is
Stored value stored in expansion amount storage 71 and expansion amount detector 1
The detection value detected by 00 is always compared. Then, the comparator 72 is preset to transmit an alarm signal when the difference between the stored value and the detected value is ± 1 V or more (changes beyond a preset range). By doing so, when the detected value rises above 9V or falls below 7V, the comparator 72 determines that the potentiometer 140 is abnormal, and sends an alarm signal to alert the alarm device 80. To operate. The alarm operation is not limited to the buzzer of the alarm device 80, but the boom operation restriction unit 90 may restrict the operation range of the boom 2 to perform the alarm operation.

As a result, the alarm can be activated not only when an abnormality occurs in the potentiometer 140 itself but also when the extension amount cannot be accurately detected due to an abnormality in the electric power supplied to the potentiometer 140.

The range in which the boom 2 can be operated when the boom 2 is restricted by the boom operation restricting means 90 is the operation range of the boom 2 when each outrigger beam is in the fully retracted position. By doing so, it is possible to prevent the vehicle body 4 from becoming unstable due to the operation of the boom 2.

Further, here, the difference between the stored value and the detected value is ± 1.
The reason why the alarm signal is transmitted when the voltage exceeds the range of V is that the outrigger expands and contracts even if there is no abnormality in the potentiometer 140 due to vibration during work or expansion and contraction of the cable 120 due to changes in temperature. This is because some fluctuations in the detected value may occur when the operation is not performed. Therefore, the value of the preset range is not limited to ± 1 V, and is set appropriately in consideration of the detected value from the fully retracted position to the fully extended position and the fluctuation of the detected value of the potentiometer 140.

Even if the potentiometer 140 is normal, when the cable 120 is disengaged from the cable holding member 130, the cable 120 is broken, or the cable 120 is slackened by an external force or the like, The alarm is also activated when a value exceeding the preset range is detected.

Further, for example, when the detected value at the extended position of the outrigger beam 11 is 8V as described above, the extension operation of the outrigger beam 11 is stopped, and then the outrigger beam 11 is reduced to the position where the originally detected value becomes 6V. It is assumed that the operation is performed to stop the reduction operation of the outrigger beam 11, but the cable 120 is caught, and the detected value remains at 8V in some cases.

After that, when the extension of the outrigger beam 11 is not performed and the catch of the cable 120 is released and an accurate detection value (6V) is detected, 6
The state in which V is detected is the normal state of the outrigger 10. However, even in this case, the outrigger beam 1
Since it is detected that the detected value has changed by more than ± 1 V in the state where the expansion / contraction operation of No. 1 is not performed, the comparator 72 performs the alarm operation. As described above, the extension amount detector 100 has been used in the past.
An alarm is activated even when an abnormality is detected in the.

Further, in the above-mentioned embodiment, the case where the outrigger safety device is used for the aerial work vehicle provided with the boom on the vehicle body which can be freely moved up and down, extended and retracted is explained. However, the vehicle body is not necessarily provided with a boom and can be used in any work vehicle as long as it is a vehicle provided with an outrigger.

[0035]

As described above, in the outrigger safety device of the present invention, the expansion / contraction amount detecting means detects the expansion / contraction amount of the outrigger beam, and the operation detecting means detects the expansion / contraction operating operation of the outrigger beam. Then, the detection value detected by the expansion / contraction amount detection means is stored as a stored value in the detection value storage means when the expansion / contraction operation of the outrigger beam is detected by the operation operation detection means, and the expansion / contraction is performed by the comparator. The detected value and the stored value in the state where the operation is not performed are compared, and when this difference changes beyond the preset range, the alarm signal is output from the comparator, and the alarm signal from the comparator The alarm means that has received the alarm is configured to perform an alarm operation. When a detection value outside the predetermined range is detected due to an abnormality in the expansion / contraction amount detecting means, an alarm operation such as an alarm buzzer and an alarm lamp is performed, so that the safety of the system provided with the outrigger is improved. Can be achieved.

[Brief description of drawings]

FIG. 1 is a side view showing an outrigger provided with an outrigger safety device according to the present invention.

FIG. 2 is a perspective view of an aerial work vehicle equipped with the outrigger safety device.

FIG. 3 is a block diagram of the safety device of the outrigger.

[Explanation of symbols]

 1 aerial work vehicle 2 boom 3 work platform 4 vehicle body 4a outrigger box 10, 20 outrigger jack device 11 outrigger beam 100 extension amount detector 110 reel 120 cable 130 cable holding member 140 potentiometer

Claims (1)

[Claims] 1. A safety device for an outrigger, which is disposed so as to be capable of expanding and contracting laterally of a vehicle body, and has a lower end grounded to support the vehicle body. Expansion / contraction amount detecting means for detecting, operation operation detecting means for detecting expansion / contraction operating operation of the outrigger, and expansion / contraction amount detecting means when the operation operation detecting means detects that the expansion / contraction operating operation of the outrigger is stopped. The detection value storage means for storing the detection value detected by, and the expansion / contraction amount detection means in a state where the expansion / contraction operation operation of the outrigger is not performed by the operation operation detection means. When the detected value and the stored value stored by the detected value storage means are compared, and when the difference between the detected value and the stored value changes beyond a value in a preset range, A comparator for outputting a broadcast signal, receiving the alarm signal from the comparator, the safety device of the outrigger, characterized in that it has a warning means for causing the alarm activation.