JPH0130970B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a device for preventing a bridge inspection vehicle or the like having a boom from overturning due to boom operation.

When extending and rotating the boom of a bridge inspection vehicle, aerial work vehicle, etc., a large overturning moment is generated not only in the loading state but also in the unloading state, so safety measures to prevent rollover are important. Usually, this type of vehicle is equipped with an auxiliary support device, or an outrigger, which protrudes to the side of the vehicle body and lowers to the ground, thereby providing a fulcrum that can withstand overturning moments and prevent the vehicle from overturning.

However, although conventional booms are equipped with outriggers, the boom can be extended regardless of whether the outriggers are securely set, and there remains a risk of overturning. Furthermore, depending on the situation at the site, the protrusion distance of the outriggers may be limited, and in such cases, the work may be dangerous because it is not possible to know the limit of stable extension of the boom.

The purpose of the present invention is to solve the above-mentioned dangers,
An object of the present invention is to provide a device that can reliably prevent rollovers.

For this purpose, the present invention sets in advance the extension limit of the boom with respect to the protrusion distance of the outriggers,
The system is characterized in that the extension operation of the boom is enabled by detecting the completion of the outrigger extension operation and the completion of the grounding, and the extension operation is enabled only within the corresponding boom extension limit based on the detection of the extension distance. do.

An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows a bridge inspection vehicle equipped with the rollover prevention device of the present invention in its operating state. This bridge inspection vehicle is equipped with an elevating boom 1 that can be controlled to extend and contract (arrow A) and to raise and lower (arrow B) so as to be controllable in rotation (arrow C). A holding device 2 is provided at the tip of the elevating boom 1 so as to be controllable pivotably (arrow D), and a vertical boom 3 is held by the holding device 2 so as to be controllable up and down (arrow E). A support stand 4 is provided at the lower end of the vertical boom 3 so as to be controllable in rotation (arrow F), and an inspection stand 5 is attached to this support stand 4 so as to be controllable in extension and contraction (arrow G) and pivoting (arrow H). ,
A handrail 5' is provided upright on the inspection table 5. still,
The handrail 5' can also be foldable. When the bridge inspection vehicle is traveling, the inspection platform 5 is rotated to the left in the figure (arrow F), and then pivoted counterclockwise (arrow H) so that it overlaps the vertical boom 3. is raised together with the inspection platform 5 (arrow E), and by pivoting the holding device 2 clockwise (arrow D) in the figure, it is brought into a state parallel to the elevating boom 1, and then the elevating boom 1 is raised together with the vertical boom 2 and the inspection platform. 5 in the longitudinal direction of the vehicle body (arrow C).

This bridge inspection vehicle also has outriggers 10 and 11.
(Here, the rear left and right sides are shown, respectively). Here, only one outrigger 10 is provided so that its operation can be controlled to protrude to the side of the vehicle body (arrow I), and the wheel 12 serving as a fulcrum can be lowered to touch the ground. Of course, the other outrigger 11 can also be controlled in a similar manner. Furthermore, since the outriggers 10 and 11 are equipped with wheels 12 and 13, they can be driven while in the working state (FIG. 1).

The operations described above are carried out here by a suitable drive source such as a hydraulic cylinder piston device and a hydraulic motor, and can be controlled by operating buttons or the like on an operation panel provided on the vehicle body.

According to the present invention, in order to detect the protrusion distance of the outrigger 10, a plurality of limit switches LS1,
LS2, LS3, and LS4 are attached to the outrigger holding cylinder 20. Here, four limit switches are shown for the left outrigger 10.
The right side can also be configured in the same way, and the number of items is 4.
It is not limited to specific items. These limit switches are configured such that, as shown in FIG. 2, for example, a shoulder 22 is formed on the outrigger moving cylinder 21 to indicate an appropriate reference position, and passage of the shoulder 22 through the holding cylinder 20 is detected by a pressing pin 23. The pin 23 can be used to turn the contact ON and OFF. In this case, the limit switch
By determining the positions of LS1 to IS4, the protrusion distances l ₁ , l ₁ +l ₂ , l ₁ +l ₂ +l 3 , l 1 +l ₂ can be changed in stages from the storage position to the maximum protrusion position as shown in Fig. _{3 .} +l ₃
+l ₄ can be detected. In this way,
Limit switches LS1 to LS4 are outrigger 1
The protrusion distance of 0 is detected in a preset stepwise manner.

The outriggers 10 and 11 also have wheels 12 and 1.
Pressure-sensitive switches LS5 and LS6 are provided here to detect when the robot 3 has been lowered and touched the ground.

The elevating boom 1 is equipped with multiple (three in this case) limit switches LS to detect the extension distance.
7, LS8, and LS9 are provided. These limit switches have the same structure as the limit switches LS1 to LS4 provided in the outrigger holding cylinder 20, and can employ the same detection method. However, other configurations are of course possible.

By the way, in order to prevent rollovers, the overturning moment
M _R must be smaller than the stabilizing moment M _S , and these moments M _R and M _S change depending on the protruding distance of the outrigger 10 when considering the work shown in Fig. 1, and at each protruding distance, If the moment ratio M _S /M _R >1, the vehicle will not roll over. Here, we consider the moment ratio M _S /M _R ≒1.3 as the standard,
The allowable extension limit of the elevating boom 1 for each protruding distance is calculated in advance. And the limit switch LS for detecting the extension distance of the elevating boom 1 mentioned above.
7, LS8, LS9 are each outrigger 10
The positions are set in advance so as to detect the extension distance corresponding to the extension allowable limit at the protrusion distances l ₁ , l ₁ +l ₂ , l ₁ +l ₂ +l ₃ .

These limit switches LS1 to LS4 detect the protrusion distance of the outrigger 10, and the limit switches LS7 to LS7 detect the extension distance of the elevating boom 1.
Based on the detection signal of the LS9, the extension operation of the elevating boom 1 is controlled as shown in FIG.

That is, as shown in Fig. 4, the limit switch
LS1 to LS4, pressure sensitive (or limit) switch LS
5, LS6 and limit switches LS7 to LS9
are normally open, and are connected so as to energize the magnet coils MLS1 to MLS9 of relays R1 to R9 and R1', respectively, when turned on. Here, relays R1, R1', R2 to R6 are closed or turned ON when magnetic coils MLS1 to MLS6 are energized, respectively, and relays R7 to R9 are connected to magnetic coils MLS7 to MLS9.
are configured to open, that is, turn OFF, when each is energized.

Relays R1, R5, R6 are connected in series and are shown by line a. Also, relays R1' and R7, R2 and R
8, R3 and R9 are connected in series, and these and relay R4 are connected in parallel as a whole and connected to line b. These lines a, b
The output is from the boom operator provided on the operation panel.
100, and the outputs of lines a and b are configured so that operations such as extension and contraction control of the elevating boom 1 can be executed or rejected. The boom operator 100 is, for example, a select switch.
By operating a group of 110 buttons, a desired operating mode (elevating boom 1, elongation and contraction, etc.) can be selectively set, and each button can be used to operate a hydraulic cylinder and a valve mechanism for controlling a hydraulic motor. The magnetic coils (M1 to M6 are shown here) are energized. Here, for example, the magnetic coil M1 is used to open and close the inspection table 5, and M2
M3 is a magnetic coil related to the rotation of the inspection table 5, M3 is an extension operation of the elevating boom 1, M4 is a retracting operation of the elevating boom 1, M5 is a magnetic coil for raising and lowering the elevating boom 1, and M6 is a magnetic coil for raising and lowering the vertical boom 3.

The rollover prevention device including the illustrated circuit of the limit switches LS1 to LS9 and associated relays R1 to R9 operates as follows.

That is, when extending the elevating boom 1 to the left side as shown in FIG. 1, if the outriggers 10 and the outriggers 11 are not projected and grounded in advance, the limit switches LS1, L5,
LS6 is at least open (OFF). accordingly
Magnetic coil MLS1, MLS5 or (and) corresponding to the limit switch that is OFF
MLS6 is not energized and similarly relays R1 and R5
or (and) R6 is also turned off and line a
is not completed. Therefore, even if the elevating boom 1 is extended using the boom operating device 100, the operation is prevented, and the risk of overturning is eliminated. Here relay R5
0 is designed to be connected and separated by a magnetic coil MLS50 that is energized and deenergized by a limit switch 50 that detects whether the inspection table 5 is fixed in rotation, and when the inspection table 5 is fixed, the relay R50 is activated.
is closed.

The line a is completed when the outrigger 10 is extended a distance l ₁ as a first step, and both the outrigger 11 and the outrigger 11 are grounded and the inspection platform 5 is pivoted and fixed. On the other hand, in line b, only R1' of relays R1' to R4 is turned on, so an output is given to boom operating device 100 through normally closed relay R7. This causes magnet coil M20 to operate and close relay R20 which communicates with magnet coil M3. This magnetic coil M
3 completes the connection to the elevating boom 1, so that the elevating boom 1 can be extended from the storage position by operating the select switch 110. However, when the limit switch LS7 detects that it has been extended to the allowable limit, the magnetic coil MLS
7 is energized, and relay R7 is opened (OFF). As a result, line b is disconnected, and relay R20 is opened by deenergizing magnetic coil M20, so that magnet coil M3 is deenergized. As a result, further extension of the elevating boom 1 is prohibited.

Next, when the protrusion distance of the outrigger 10 is set to l ₁ +l ₂ as a second stage and both the outrigger 11 and the outrigger 11 are grounded, the line a is completed. On the other hand, in line b, limit switches LS1 and LS2
As a result of the operation, R1' and R2 of relays R1' to R4 are turned on, and line b is completed through normally closed relays R7 and R8, respectively. This allows the elevating boom 1 to be extended. When the elevating boom 1 is extended to the allowable limit in the first stage described above and the limit switch LS7 detects this, the relay R7 is opened (OFF). However, since relay R8 is closed, line b still remains closed, allowing the elevating boom 1 to be further extended. The elevating boom 1 is extended to the permissible limit of the second stage and the limit switch is activated.
When LS8 detects this, magnet coil MLS8 is energized and relay R8 is opened (OFF).
As a result, line b is disconnected, and further extension of the elevating boom 1 is prohibited by deenergizing the magnet coil M20 and opening the relay R20.

Furthermore, when the protrusion distance of the outrigger 10 is set to l ₁ +l ₂ +l ₃ as the third stage and both the outrigger 11 and the outrigger 11 are grounded, line a is completed, and relays R1', R2, and R3 are closed in line b. be completed. This similarly allows the elevating boom 1 to extend until the limit switch LS9 is actuated and opens the relay R9, thereby ensuring extension up to the permissible limit in the third stage and exceeding this limit. Excessive elongation is prevented.

Furthermore, when the outriggers 10 are protruded to the maximum extent, the elevating boom 1 can be extended to that limit. In addition, in this embodiment, the outrigger 10
l ₁ protrusion and grounding are prerequisites for boom extension, but the present invention is not limited to this, and if necessary, only the grounding of the outrigger 10 may be a prerequisite (in Fig. 4, LS1-MLS1〓R1 (excluding R1).

When retracting the elevating boom 1 in the storage direction, there is no risk of it overturning with this operation, so relay R2
0, the magnet coil M4 for retracting the elevating boom 1 can be connected without using a release switch.

As described above, according to the present invention, the extension limit of the elevating boom can be safely and reliably determined with respect to the amount of protrusion of the outrigger depending on the site, so that a significant effect in terms of safety can be obtained.

[Brief explanation of drawings]

FIG. 1 is a rear elevational view showing a bridge inspection vehicle equipped with the rollover prevention device of the present invention as an embodiment. FIG. 2 is a partial sectional view showing a schematic structure of an embodiment of a limit switch. FIG. 3 is a partial explanatory diagram schematically showing the protrusion of the outriggers and the arrangement of limit switches for detecting the protrusion. FIG. 4 is a circuit diagram schematically showing a signal processing circuit for each limit switch of the rollover prevention device in the bridge inspection vehicle shown in FIG. 1. 1...Elevation boom, 2...Holding device, 3...Vertical boom, 4...Support stand, 5...Inspection stand, 10,
11... Outrigger, 12, 13... Wheel, 2
0...Holding tube, 22...Shoulder, 23...Press pin, 100...Boom operator, LS1 to LS9...
...Limit switch, MLS1 to MLS9...Magnetic coil, M1 to M6, M20, M50...
Magnetic coil, R1-R9, R20, R50
……relay.

Claims (1)

[Scope of Claims] 1. A rollover prevention device for a vehicle such as a bridge inspection vehicle, which has a telescopic boom and an outrigger for forming a fulcrum at a position protruding to the side of the vehicle body, which prevents the outrigger from grounding. or a first means for detecting completion of the grounding and ejection operations, a second means for detecting an ejection distance of the outrigger, and a third means for detecting an extension distance of the boom;
The control circuit is energized to enable the boom to be extended by the detection signal by the second means, and the control circuit is enabled to extend the boom within a predetermined permissible limit in response to the detection signal by the second means. A bridge inspection vehicle or the like characterized in that the control circuit is energized and the control circuit is cut off so as to disable the extension operation when the set permissible limit is exceeded by the third means. Rollover prevention device. 2 A first set of multiple relays that are turned on in response to the amount of horizontal extension of the outriggers and a second set of multiple relays that are turned off in accordance with the amount of extension of the boom are configured to correspond to the amount of extension of the outriggers and the boom. are connected in series to each other, and when the amount of extension of the boom exceeds a set limit with respect to the amount of extension of the outriggers, the extension operation circuit is cut off by the plurality of relays of the second set. A boom-based rollover prevention device for bridge inspection vehicles, etc. as described in Scope 1.