JP2553246Y2 - Outrigger jack ground contact detection device - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an outrigger jack for supporting a vehicle body of a working vehicle with respect to the ground.
The present invention relates to a ground state detection device that detects a ground state of an outrigger jack.

[0002]

2. Description of the Related Art Outrigger jacks are often attached to the front, rear, left and right sides of a body of a working vehicle having a working device mounted on the body. The outrigger jack includes an outer post attached to a side surface of a vehicle body and the like, and a jack cylinder attached inside the outer post. The jack cylinder extends downward and the lower end thereof is grounded, so that the vehicle body can be supported on the ground via the outer post.

Here, the jack cylinder is attached to the outer post with a play that allows a slight vertical movement. For this reason, when the vehicle body is tilted with the operation of the working device, the outer post is lifted upward with respect to the jack cylinder by the amount of the play while the jack cylinder is kept in contact with the ground with the tilt. The relative movement between the outer post and the jack cylinder is detected by a limit switch or the like, and a safety device is configured to regulate the operation of the working device assuming that the vehicle body has fallen into an unstable state. As a result, an accident such as a fall of the vehicle body is prevented, and work safety is ensured.

[0004]

However, with such a safety device, the operator cannot move the vehicle body until the relative movement between the outer post and the jack cylinder is completed and the operation of the working device is restricted. You can only recognize that you are in a state. For this reason, for example, when the operator wants to operate the working device to the target operation state, it is not possible to determine whether the target operation state can be reached until the operation is actually restricted. However, there is a problem that it is not preferable in terms of work efficiency.

The present invention has been made in view of such a problem, and recognizes that the vehicle body is approaching such an unstable state before the vehicle body reaches the unstable state. It is an object of the present invention to provide an apparatus for detecting a ground contact state of an outrigger jack which is used to enable the contact.

[0006]

In order to achieve the above object, in the grounding state detecting device according to the present invention, a fixing member is fixed to the outer post above the jack cylinder inside the outer post. A movable member disposed between the fixed member and the upper end of the jack cylinder is movably provided in a vertical direction while being urged downward by a spring disposed between the fixed member and the movable member. The fixed member has a first detection switch (limit switch) that outputs a detection signal when the pressing operation is released, and a second detection switch (limit switch) that outputs a detection signal when the pressing operation is performed. Switch) is attached. The movable member is provided with an operating member that moves up and down integrally with the movable member and abuts on and operates the first detection switch and the second detection switch. When it is located at the lower end position in the vertical movement allowable range due to play provided between the two, only the first detection switch is pushed by the operating member, and the outer post is connected to the jack cylinder. On the other hand, when it is located at the predetermined intermediate position in the movement allowable range, the pushing operation of the first detection switch by the operating member is released, and the pushing operation of the second detection switch is not performed. When the jack cylinder moves upward beyond the predetermined intermediate position, the second detection switch is pushed by the operating member. It is to be created.

[0007]

According to such a contact state detecting device, when the outer post moves upward to a predetermined intermediate position with respect to the jack cylinder as the vehicle body approaches the unstable state and tilts, the first operation member is used. The operation of the detection switch is released, and a detection signal is output from the first detection switch.
Therefore, if an alarm is sounded based on the detection signal, the worker can be made aware that the vehicle body is approaching an unstable state.

Further, when the outer post has moved upward beyond the predetermined intermediate position with respect to the jack cylinder when the vehicle body has fallen into an unstable state, the second detecting switch is pushed by the operating member, and the second detecting switch is operated. A detection signal is output from the switch. Therefore, for example, by restricting the operation of the working device based on the detection signal, it is possible to prevent the vehicle body from overturning.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below with reference to the drawings. First, FIG. 1 shows an aerial work vehicle 10 including the outrigger jack grounding state detecting device according to the present invention. The body 11 of this aerial work vehicle 10
At the rear of the vehicle, a swivel 12 that can freely swing horizontally with respect to the vehicle body 11 is attached. Further, a boom 13 which is configured to be telescopically extendable and retractable is attached to the upper portion of the swivel base 12 so as to be able to move up and down. Further, a work table 14 is horizontally attached to the tip of the boom 13, and an operator (not shown) boarding the work table 14
The user can move to an arbitrary height through the operation of the turntable 12 and the boom 13.

However, when the boom 13 or the like is operated, a moment based on the weight of the boom 13 and the workbench 14 (hereinafter referred to as a “overturning moment”) acts on the vehicle body 11 in a direction in which the vehicle body 11 falls. For this reason, outrigger jacks 15 that support the vehicle body 11 with respect to the ground are attached at four positions on the front, rear, left, and right sides of the vehicle body 11.

The outrigger jack 15 is mounted on the vehicle body 11.
The outer post 16 is attached to a side surface of the outer post 16, an inner post 17 is inserted into the outer post 16 so as to be able to expand and contract in the up-down direction, and a jack cylinder 18 built in the both posts 16,17. The jack cylinder 18 is, as shown in FIG.
The outer post 1 is inserted into the holding hole 18b formed at the upper end of the outer post.
6 is held by the outer post 16 by penetrating a holding pin 16a attached so as to be bridged between the side plates facing each other. The holding hole 8b
The inner diameter of the outer post 1 is larger than the outer diameter of the holding pin 16a.
6 is held in a state in which there is a play that allows movement in the vertical direction.

Then, the inner post 17 connected to the lower end of the jack cylinder 18 is extended downward, and the lower end of the inner post 17 is grounded, so that the jack cylinder 18 is connected to the vehicle body 11 via the outer post 16. Can be supported against the ground.

The ground state detecting device according to the present invention is mounted inside the outer post 16 of each of the outrigger jacks 15 configured as described above. Hereinafter, the ground state detecting device will be described with reference to FIG. The grounding state detecting device 20 includes a fixed member 21 and a movable member 22.
And two detection switches (a first detection switch 23 and a second detection switch 24) and an operation arm 25. The fixing member 21 is connected to the cylinder tube 18 of the jack cylinder 18 inside the outer post 16.
a and is fixed to the outer post 16. The fixing member 21 is provided with a disk portion, and a through hole 21a is formed in the center of the disk portion so as to penetrate vertically.

The movable member 22 is disposed between the fixed member 21 and the upper end of the cylinder tube 18a.
1, and is movably provided in the vertical direction while being urged downward by a double spring 26 disposed between the two springs. The movable member 22 is a disk-shaped member, and has a through-hole 22a penetrating in the vertical direction at the center thereof. The through-hole 22a and the through-hole 21 formed in the fixing member 21 are formed.
One of the stopper bolts 27 is inserted into a of FIG.

At the upper end of the stopper bolt 27,
A stopper nut 28 is attached, and the contact between the stopper nut 28 and the fixed member 21 prevents the movable member 22 urged downward by the double spring 26 from moving below a certain position. You.

The first detection switch 23 comprises a limit switch, and is attached to the outer peripheral surface of a spring cover 21b which extends downward from the lower surface of the fixed member 21 in a cylindrical shape.
The first detection switch 23 has a switch rod 23
a is turned off in a state where it is operated to be pushed upward, and is turned on when the operation is released to output a detection signal. The second detection switch 24 also includes a limit switch, and is attached to a side surface of the fixed member 21. The second detection switch 24 is turned on when the switch rod 24a is operated so as to be pushed downward, and outputs a detection signal.

The operation arm 25 is integrally attached to the lower surface of the movable member 22, and moves up and down together with the movable member 22. The right end of the operation arm 25 extends to below the first detection switch 23, and the tip thereof has a first end.
A screw 25a is attached to face the lower end of the switch rod 23a of the detection switch 23. The left end of the operation arm 25 extends to above the second detection switch 24, and a distal end thereof has a screw 25 facing the upper end of the switch rod 24 a of the second detection switch 24.
b is attached.

The detection signals output from the first detection switch 23 and the second detection switch 24 are input to the controller 51 of the safety device 50 shown in FIG.
When receiving the detection signal from the first detection switch 23, the controller 51 activates the alarm 52 to sound an alarm. Further, the controller 51 is provided with the second detection switch 24.
When the detection signal is received from the boom, the boom restricting device 53 is operated to forcibly stop the operation of the boom 13 in the direction of increasing the overturning moment (falling operation or extension operation).

The grounding state detecting device 2 thus configured
At 0, the lower end surface of the head portion of the stopper bolt 27 urged downward by the double spring 26 always contacts the upper end surface of the contact screw 18c attached to the upper end portion of the cylinder tube 18a of the jack cylinder 18.

Here, FIG. 2 shows the outrigger jack 15.
Indicates a state in which the vehicle body 11 is stably supported. That is, the weight of the vehicle body 11 is deposited in the jack cylinder 18 via the outer post 16, and the holding pin 16a of the outer post 16 is
Is located at the lower end position with respect to the holding hole 18b. Therefore, the movable member 22 and the operation arm 25 are connected to the cylinder tube 18 via the head of the stopper bolt 27.
a pushes upwards against the urging force of the double spring 26. In this state, the right end of the operation arm 25 comes into contact with the switch rod 23a of the first detection switch 23 and pushes up the switch rod 23a.
Does not output a detection signal. On the other hand, the operation arm 25
Is the switch rod 24a of the second detection switch 24.
, The detection signal is not output from the second detection switch 24 either.

FIG. 3 shows a state where the vehicle body 11 is leaning toward an unstable state. That is, although the jack cylinder 18 is grounded, the weight of the vehicle body 11 does not depend on the jack cylinder 18 and the outer post 16
The holding pin 16a is connected to the holding hole 1 of the jack cylinder 18.
8b is in a state of being floating with respect to the jack cylinder 18 so as to be located at the center (predetermined intermediate position) of the jack cylinder 18. At this time, the movable member 22 and the operation arm 25 are located slightly below the state shown in FIG. And
In this state, since the right end of the operation arm 25 is detached from the switch rod 23a of the first detection switch 23,
A detection signal is output from the detection switch 23. Therefore, the above-described alarm 52 is activated, and the worker who hears the alarm can recognize that the vehicle body 11 is approaching an unstable state.

Further, the worker who recognizes that the vehicle is approaching the unstable state as described above indicates how much the boom 13 can be moved to the unstable side and the work table 14 can be moved at that time. It can also be considered. Therefore, when trying to move the workbench 14 to a certain target position, it is possible to determine whether or not it is possible in the middle of the movement, and unnecessary operation of the boom 13 can be avoided beforehand, thereby improving work efficiency. Can be improved.
Since the left end of the operation arm 25 is still detached from the switch rod 24a of the second detection switch 24,
No detection signal is output from the second detection switch 24.

FIG. 4 shows a state in which the vehicle body 11 has fallen into an unstable state and is tilted more greatly than the state shown in FIG. That is, the holding pin 16a of the outer post 16 lifted together with the vehicle body 11 is located at a position where it contacts the upper end of the holding hole 18b of the jack cylinder 18 (a position beyond a predetermined intermediate position), and the lower end of the jack cylinder 18 is separated from the ground. Let it. At this time, the movable member 22 and the operation arm 25 have been lowered to a position where the stopper nut 28 contacts the fixed member 21. In this state, since the right end of the operation arm 25 is separated from the switch rod 23a of the first detection switch 23, a detection signal is output from the first detection switch 23. On the other hand, the left end of the operation arm 25 is
Since the switch rod 24a of the second detection switch 24 is contacted and pushed downward, the detection signal is also output from the second detection switch 24. For this reason, the boom restricting device 53 operates to restrict the operation of the boom 13 to the unstable side, thereby preventing the vehicle body 11 from falling over.

[0024] Even if the switch rod 24a of the second detection switch 24 freezes due to the work performed in the cold area using the high-altitude work vehicle 10, the second detection switch 24 is still connected to the switch rod 24a. , The detection signal is output by the push operation, so that the operation of the boom regulating device 53 is not hindered by such freezing.

[0025]

As described above, the contact state detecting device of the present invention indicates that not only the contact state of the outrigger jack indicating that the vehicle body has fallen into an unstable state, but also that the vehicle body is approaching the unstable state. Also detects the grounding condition. For this reason, the use of the ground contact state detection device allows the operator to recognize that the vehicle body is approaching such an unstable state before the vehicle body falls into an unstable state, and furthermore, the vehicle body is unstable. The work efficiency can be improved by giving an estimate of how much extra time is left before the state is reached.

[Brief description of the drawings]

FIG. 1 is a perspective view of an aerial work vehicle equipped with a device for detecting a ground contact state of an outrigger jack according to the present invention.

FIG. 2 is a side view of the ground detection device.

FIG. 3 is a side view of the grounding state detecting device.

FIG. 4 is a side view of the grounding state detecting device.

FIG. 5 is a block diagram of a safety device using the ground detection device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Aerial work vehicle 11 Body 15 Outrigger jack 16 Outer post 16a Holding pin 17 Inner post 18 Jack cylinder 18b Holding hole 20 Grounding state detecting device 21 Fixed member 22 Movable member 23 First detection switch 24 Second detection switch 25 Operation arm 26 Double spring

Claims (1)

(57) [Scope of request for utility model registration] 1. An outer post attached to a side portion of a vehicle body of a work vehicle and the like, and a jack cylinder attached to the outer post with a play that allows vertical movement of the outer post relative to the outer post, A ground contact detection device for an outrigger jack that supports the vehicle body with respect to the ground by extending the jack cylinder downward and contacting a lower end portion thereof, and is disposed above the jack cylinder inside the outer post. A fixing member fixed to the outer post; and a movable member arranged between the fixing member and the upper end of the jack cylinder, and vertically movable while being urged downward by a spring disposed between the fixing member and the fixing member. A movable member provided on the fixed member, and A first detection switch that outputs a detection signal when the pushing operation is released, and a limit switch that is attached to the fixing member so that the pushing operation can be performed. A second detection switch that outputs a detection signal to the movable member; and a second detection switch that is integrally attached to the movable member, moves up and down with the movable member, and moves up and down together with the first detection switch and the second detection switch.
An operating member that abuts against the detection switches and pushes the detection switches, and the outer post is located at a lower end position in a vertical movement allowable range with respect to the jack cylinder by the play. When, only the first detection switch is pushed by the operating member, and when the outer post moves up to a predetermined intermediate position within the movement allowable range with respect to the jack cylinder,
The pressing operation of the first detection switch by the operating member is released, and the pressing operation of the second detection switch is not performed, and the outer post allows the movement of the jack cylinder relative to the jack cylinder. An outrigger jack contact state detecting device, wherein the second detection switch is pushed by the operation member when the second detection switch is moved upward beyond the predetermined intermediate position within the range.