JPH0427726Y2 - - Google Patents

Description

[Detailed description of the invention] (1) Industrial application field The present invention pivots a jack box at the tip of an extensible outrigger beam via a horizontal rotation pin so that it can swing freely in the front and rear directions of the vehicle body. This invention relates to a safety device for an outrigger that allows a jack box to be swung and held in a vertical or horizontal position so that it can be extended over an obstacle.

(2) Conventional technology A jackbox is pivoted so as to be swingable in the longitudinal direction of the vehicle body via a horizontal rotation pin at the tip of an outrigger beam, and the jackbox is swingable and held in a vertical or horizontal position. As a safety device for such an outrigger, the one described in Japanese Utility Model Application Publication No. 153659/1983 which restricts the expansion and contraction of a jack box is known.

(3) Problems to be solved by the invention However, the safety device described in Japanese Utility Model Application Publication No. 153659/1987 allows the jack box to expand and contract only when the jack box is fixed in a vertical position. , interference between the jackbox and the vehicle body due to swinging of the jackbox from a vertical position to a horizontal position without extending the outrigger beam beyond a certain length, and interference between the jackbox and the vehicle body when the jackbox is not in a vertical position. It was not possible to prevent damage to the car body due to interference between the jack box and the car body due to the reduction.

(4) Means for Solving the Problems In order to solve the above problems, the present invention provides a jack box that is installed in the longitudinal direction of the vehicle body via a horizontal pivot pin at the tip of an outrigger beam that extends and retracts with respect to the vehicle body. In the outrigger, the jack box is pivoted to be pivoted to the vertical position, and the jack box is swingable and held in a vertical or horizontal position. The outrigger beam is equipped with a position detector that detects whether the outrigger beam is extended or not, and when the length detector detects that the outrigger beam has been extended beyond a certain length when the outrigger beam is extended, the jackbox can be swung from a vertical position to a horizontal position. When the outrigger beam is stored, the outrigger beam can be stored only when the position detector detects that the jackbox is in the vertical position.

(5) Effect With the above configuration, when installing the outriggers from the retracted state, the outrigger beam is extended beyond a certain level, and then the jackbox is swung from the vertical position to the horizontal position. When the outriggers are to be retracted, the jackbox is Swing to vertical position and then fully retract the outrigger beam.

(6) Examples Examples of the present invention will be described below with reference to the drawings.

As shown in FIGS. 3 and 4, outriggers 2, 3 are mounted on the left and right sides of the vehicle body 1 of the work vehicle, respectively.
4 and 5, and an aerial work device 6 is mounted on the vehicle body 1.
The outriggers 4 and 5 on the right side of the car body 1 are conventional ones that protrude to the side of the car body 1 and extend downward to support the car body 1.
As shown in FIG. 5, the left outriggers 2 and 3 have an outrigger beam 20 slidably inserted into the outrigger box of the vehicle body 1, and the outrigger beam 20 is extended and retracted by the expansion and contraction of a built-in extension cylinder 21. At the tip of the outrigger beam 20, a jack box 23 is pivotally supported by a horizontal rotation pin 22 so as to be swingable in the longitudinal direction of the vehicle body 1, and the jack box 23 is provided between the tip of the outrigger beam 20 and the jack box 23. It swings between a vertical state and a horizontal state by the expansion and contraction of the swing cylinder 25, and the jack box 23 expands and contracts by the expansion and contraction of the built-in jack cylinder 24, so that the outrigger beam 20 should not be extended beyond a certain length. If the jack box 23 is swung from the vertical position to the horizontal position, or if the outrigger beam 20 is reduced to a certain length or less when the jack box 23 is not in the vertical position, the jack box 23 will collide with the vehicle body 1, causing the vehicle body 1 to fall into disrepair.

Figure 2 shows the overhanging cylinder 21 and the swinging cylinder 2.
5, the operating valve 9 to which discharge oil of the pump 10 is supplied is connected to the bottom side and the rod side of the overhanging cylinder 21, respectively, and the pipe line connecting the operating valve 9 and the bottom side of the overhanging cylinder 21. A stop valve 7 is inserted in the pipe, a switching valve 8 is inserted in the pipe between the stop valve 7 and the operating valve 9, and the pipe connected to the switching valve 8 is connected to the bottom side of the swing cylinder 25. A pipe line branching from a pipe line connecting the operating valve 9 and the rod side of the overhanging cylinder 21 is connected to the rod side of the swing cylinder 25.

FIG. 1 shows an electric circuit diagram, which is a length detector that detects the extension/contraction length of the outrigger beam 20, and when the outrigger beam 20 is less than a certain length.
A limit switch 26 that turns on is connected to the first relay 13, and is a position detector that detects whether the jack box 23 is in the vertical position.A limit switch 27 that turns on when the jack box 23 is held in the vertical position is connected to the second relay 14, and the first
The B contact 15 of the relay 13 and the B contact 16 of the second relay 14 are connected in parallel with the A contact 17 of the second relay 14, and this circuit is connected in series with the solenoid 70 of the stop valve 7, and the changeover switch 29 is
The B contact 18 of the first relay 13 is connected in series with a circuit in which the A contact 19 of the first relay 13 and the B contact 28 of the second relay 14 connected in series are connected in parallel. It is connected in series with the solenoid 80 of the switching valve 8.

With the above configuration, when the outriggers 2 and 3 are in the retracted state, as shown by solid lines in FIGS. 3 and 4, the limit switch 26 of the length detector and the limit switch 27 of the position detector are both turned on, and the limit switch 27 of the position detector is turned ON. Contacts 17, 19 are closed, B contacts 15, 1
6, 18, and 28 open, the solenoid 70 is energized, but the solenoid 80 is not energized,
Stop valve 7 is switched to position b, but switching valve 8 is switched to position a.
Since the outrigger beam 20 is held in this position, the overhanging cylinder 21 can be expanded or contracted by switching the operating valve 9, and the outrigger beam 20 can be expanded or contracted. However, even if the switching switch 29 is closed, the switching valve 8 does not switch to the b position. , it is not possible to swing the jack box 23 by expanding and contracting the swing cylinder 25.

When the overhang cylinder 21 is extended from the retracted state and the outrigger beam 20 is extended beyond a certain length, the limit switch 27 remains ON, but the limit switch 26 is turned OFF.
Since the B contact 18 closes, the switching valve 8 is switched to the b position by closing the switching switch 29, and the swing cylinder 2 is switched by switching the operating valve 9.
5 can be expanded and contracted to swing the jack box 23 to a horizontal position.

While the jack box 23 is swung to the horizontal position, the outrigger beam 20 is further extended,
The outrigger 2 is installed by returning the jack box 23 to the vertical position and extending it.

When retracting the outriggers from the installed state, conversely to the above, reduce the jack box 23, and while the jack box 23 is swung to the horizontal position, reduce the outrigger beam 20, so that the outrigger beam 20 is longer than a certain length. In this state, the jack box 23 is swung to the vertical position to completely reduce the outrigger beam 20, but when the jack box 23 is swung to the horizontal position and the outrigger beam 20 is reduced to less than a certain length,
Limit switch 26 turns on, B contact 1
5 and 18 open, and the A contact 19 closes, so when the changeover switch 29 is closed, the solenoid 80 of the changeover valve 8 is energized, but the solenoid 70 of the stop valve 7 is de-energized, and the stop valve 7 is closed. position, the contraction operation of the overhanging cylinder 21 is stopped, and a collision between the jack box 23 and the vehicle body 1 is prevented.

When the reduction operation of the outrigger beam 20 has stopped, close the changeover switch 29 and close the changeover valve 8.
The limit switch 2
7 is turned on, the B contact 28 opens, the power to the solenoid 80 is cut off, the switching valve 8 is switched to the a position, the supply of pressure oil to the swing cylinder 25 is stopped, and the A contact 17 is closed. Solenoid 70
Since the stop valve 7 is energized, the stop valve 7 is switched to the b position, and by switching the operation valve 9, the overhanging cylinder 21 can be further contracted and the outrigger can be retracted.

(7) Effects of the invention As described above, according to the invention, the jackbox is pivotally supported in the longitudinal direction of the car body via a horizontal rotation pin at the tip of the extensible outrigger beam, and the jackbox is For outriggers that can be extended over obstacles by swinging and holding them in a vertical or horizontal position, the jackbox can be moved from the vertical position to the horizontal position without extending the outrigger beam beyond a certain length. To prevent damage to the car body due to interference between the jack box and the car body due to rocking, and interference between the jack box and the car body due to reduction of the outrigger beam to a certain length or less when the jack box is not in a vertical position. Therefore, the present invention is effective in improving the safety of an outrigger in which a jackbox is pivoted so as to be swingable in the longitudinal direction of the vehicle body via a horizontal rotation pin at the tip of an extensible outrigger beam.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention. Figure 1 is an electrical circuit diagram of the safety device, Figure 2 is a hydraulic circuit diagram of an overhang cylinder and swing cylinder, and Figure 3 is a side view of an aerial work vehicle equipped with outriggers. FIG. 4 is a plan view of the same, and FIG. 5 is a detailed view of the outrigger. 1...Vehicle body, 7...Stop valve, 8...Switching valve,
20... Outrigger beam, 21... Extended cylinder, 23... Jacket box, 25... Swing cylinder, 26... Length detector (limit switch), 27... Position detector (limit switch).

Claims (1)

[Scope of utility model registration request] A jackbox is pivotally supported in the longitudinal direction of the car body via a horizontal rotation pin at the tip of an outrigger beam that extends and contracts with respect to the car body, and the jackbox is swinged and held in a vertical or horizontal position. This outrigger is equipped with a length detector for detecting the extension/contraction length of the outrigger beam, and a position detector for detecting whether the jack box is in a vertical position. When it is detected that the jack box has been extended beyond a certain length, the jack box can be swung from a vertical position to a horizontal position, and when stored, only when the position detector detects that the jack box is in the vertical position. , an outrigger safety device characterized in that the outrigger beam is configured to be retractable.