JP2766232B2 - Jack grounding detector - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a jack device arranged on a working vehicle such as an aerial work vehicle, a crane truck or the like to ensure stability during work. The present invention relates to a ground detector provided.

[0002]

2. Description of the Related Art A work vehicle such as an aerial work vehicle and a crane vehicle is generally provided with a boom that can freely operate such as turning, raising and lowering, and expanding and contracting, on a movable vehicle body. When working with such a work vehicle, a moment that causes the work vehicle to overturn the vehicle body from the vehicle body position toward the boom tip in accordance with the boom, extension, etc. of the loaded boom (Hereinafter referred to as a “falling moment”) acts. Since the overturning moment increases in accordance with the increase of the load, the extension operation of the boom, etc., in order to increase the stability of the vehicle body, the vehicle body is stabilized by lifting the vehicle body against the ground. A jack device is often provided in a work vehicle.

Conventionally, as such a jack device, for example, there is an outrigger jack device 110 shown in FIG. The outrigger jack device 110 includes an outrigger box 111 fixed to a vehicle body frame and extending in a lateral direction.
An outrigger beam 112 that extends and contracts with respect to the outrigger box 111 is inserted therein.
Further, at the outer end of the outrigger beam 112, an outrigger jack 115 is provided so as to be able to extend and contract downward. The outrigger jack 115 includes an outer post 116 fixed to the tip of the outrigger beam 112.
An inner post 117 inserted into the outer post 116 so as to be able to move up and down; a ground plate 118 disposed at a lower end of the inner post 117;
And a jack cylinder 119 for driving the inner post 117 to move up and down.

At the time of work, the outrigger jack 115 is first extended by a predetermined amount in consideration of the state of the work site, work contents, and the like. After projecting the outrigger jack 115 to the side of the vehicle body, the jack cylinder 119 is extended and the ground plate 118 is grounded. After the touchdown, the vehicle body is stably supported by lifting the vehicle body against the ground G. Conventionally, as a means for detecting whether the outrigger jack 115 is correctly installed, that is, whether or not a drag is acting on the ground G, a conventional outrigger box 11 is used.
A limit switch 121 is disposed on the upper surface of the distal end portion of the sensor 1 such that its detection portion is in contact with the upper surface of the outrigger beam.

[0005] The limit switch 121 detects that the outrigger beam 112 changes its position upward with respect to the outrigger box 111 when the outrigger jack 115 presses the ground G. That is, the detection unit is pushed by the outrigger beam 112 and the limit switch 1
Since the switch 21 is turned on, the grounding of the outrigger jack 115 is confirmed.

By the way, since the outrigger beam 112 projects from the outrigger box 111, the upper surface of the outrigger beam 112 with which the detecting portion of the limit switch 121 abuts during operation.
You will be exposed to the outside. The outrigger box 11 is used to remove dirt and dust that has fallen on this surface during work.
Conventionally, a band-shaped sweeper 122 for wiping the upper surface of the outrigger beam 112 is provided at the upper end of one end (see FIG. 4).

[0007]

In the manner in which the sweeper is provided as described above, the soil or the like that has just come down is easily removed from the upper surface of the outrigger beam. Is difficult to remove. If foreign matter is significantly attached to the upper surface of the outrigger beam, the limit switch may mistakenly recognize this foreign matter as grounding of the outrigger jack. Further, even if a part of the deposit is removed by the sweeper, a new deposit is started on the portion and the deposit may be deposited, which may disturb the intended operation of the limit switch, which is not preferable.

A jack cylinder 119 is provided in the outrigger jack 115, and a hydraulic control valve 113 is provided on the top surface of the tip of the outrigger beam 112 to control the jack cylinder 119 (FIG. 4).
reference). For this reason, there is also a problem that a sufficient space for disposing the sweeper 122 cannot be obtained. At the time of full contraction of the outrigger beam 112, if an attempt is made to secure enough space so that the tip of the sweeper 122 does not interfere with the oil supply hose 114 to the hydraulic control valve 113, the outrigger beam 112 is stored in the outrigger box 111. In this case, too, the distal end side must be exposed to the outside by the space of the sweeper 122, which is not preferable.

The present invention has been made in view of such a problem, and an object of the present invention is to provide a jack grounding detector provided with a sweeper that is compactly disposed on the upper surface of an outrigger beam and that can reliably remove foreign matter adhering thereto. The purpose is.

[0010]

In order to achieve the above object, in the jack grounding detector of the present invention, a detection switch is attached to an outrigger box so that a detection portion contacts an outrigger beam. In addition, a sweeper surrounding the detection section of the detection switch is provided so as to be slidable up and down with respect to the outrigger box, and an urging means is provided between the sweeper and the detection switch. It is further preferable that height adjustment means for vertically adjusting the position of the detection switch with respect to the outrigger box is provided.

[0011]

According to the jack grounding detector of the present invention, the detection portion of the detection switch is brought into contact with the outrigger beam, and the vertical displacement of the outrigger beam with respect to the outrigger box is detected. When the outrigger beam slides inside the outrigger box in order to protrude or retract, the sweeper slidable up and down is always pressed against the outrigger beam by the urging means while surrounding the detection portion of the detection switch. Relatively slide on the outrigger beam. At this time, the sweeper sweeps the outrigger beam so as to remove foreign matter from the surface of the outrigger beam that comes into contact with the detection unit of the detection switch while surrounding the detection unit of the detection switch.

Foreign matter such as mud and ice adhering to the outrigger beam hits the sweeper when the sweeper slides relative to the outrigger beam, and is crushed. It is removed to the side from the part. Since the detection unit of the detection switch is protected by the sweeper in this manner, it does not occur that foreign matter enters the sweeper and the operation of the detection switch is not hindered, which is not only advantageous in terms of maintenance but also advantageous. Work vehicle safety is also improved.

When height adjustment means for adjusting the vertical position of the detection switch with respect to the outrigger box is provided, the degree of contact between the detection section of the detection switch and the outrigger beam can be adjusted. The sensitivity of the grounding detector can be adjusted.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below with reference to the drawings. FIG. 3 shows an aerial work vehicle 10 in which the jack grounding detector of the present invention is disposed. This aerial work vehicle 10 generally includes a vehicle body portion and a boom portion. The vehicle body is mainly mounted on the vehicle body 11, such as a self-propelled vehicle body 11 having driving wheels, a boom drive source such as a hydraulic pump (not shown) disposed in the vehicle body 11, and the like. And a boom operation control unit such as a controller (not shown). Also, the front, rear, left and right of the vehicle body 11 are extended,
An outrigger jack device 20 that stably supports the vehicle body 11 during work by grounding is provided.

A turntable 12 is provided on the vehicle body 11, and the turntable 12 is rotatable by a hydraulic motor (not shown) provided inside the vehicle body 11. A boom 13 is pivotally supported by a support shaft at the upper end of the swivel base 12, and an up-and-down cylinder 15 is fixed to the boom 13 from the swivel base 12. The boom 13 can be freely raised and lowered by the raising and lowering cylinder 15. The boom 13 includes a plurality of boom members 13a, 13b, and 13c, which are telescopically assembled, and can be freely extended and retracted by a telescopic cylinder (not shown) provided in the boom.

A vertical post 18 is pivotally supported at the distal end of the distal end boom member 13c, and a work table 17 is attached to the vertical post 18 via a bracket. The vertical post 18 is always kept perpendicular to the ground by the leveling cylinders 14a and 14b, regardless of the up-and-down state of the boom 13. For this reason, the bottom surface of the worktable supported by the vertical post 18 is always kept parallel to the ground so that the worker can work comfortably.

Next, the jack grounding detector of the present invention is shown in FIG.
This will be described with reference to FIG. FIG. 2 shows the outrigger jack device 20. The outrigger jack device 20 is provided with an outrigger beam 22 which is fixed to a frame of the vehicle body and extends leftward and rightward to extend and contract freely with respect to the outrigger box 21.
Is inserted, and an outrigger jack 25 is provided at an outer end of the outrigger beam 22. Further, the outrigger jack 25 includes an outer post 26 fixedly mounted at the tip of the outrigger beam 22 and an inner post 27 inserted into the outer post 26 so as to be able to move up and down.
And a ground plate 2 disposed at the lower end of the inner post 27.
And 8. Note that jack cylinders (not shown) are disposed in the posts 26 and 27, respectively.
The inner post 27 can be raised and lowered freely by the operation of the hydraulic control valve 23. When the inner post 27 is lowered, the ground plate 28 is grounded.

At the time of the work, the outrigger beam 22 is first extended by a desired amount and the outrigger jack 25 is extended to the side of the vehicle body in consideration of the situation of the work site and the contents of the work.
Thereafter, the jack cylinder is extended, the inner post 27 is extended downward with respect to the outer post 26, and the ground plate 28 is grounded. After grounding, the inner post 27
Of the vehicle body 11 with respect to the ground by extending
To stabilize the vehicle body 11. As described above, the outrigger jack 25 is protruded to the side of the vehicle body 11 to support the vehicle body 11, so that the stability of the vehicle body 11 during operation is ensured.

In this aerial work vehicle 10, the floor area occupied by the front, rear, left and right grounding plates 28 when the vehicle body 11 is supported by the outrigger jack 25 according to the stepwise width of the outrigger beam 22 is determined. Depending on the boom 13
The work range is regulated in which the range of the turning operation of the vehicle is regulated. Therefore, it is necessary to confirm whether each outrigger jack 25 lifts and supports the vehicle body 11. As a means for easily detecting this confirmation, the jack grounding detector 40 of the present invention is disposed on the upper surface of the tip of the outrigger box 21.

The jack grounding detector 40 is disposed on the upper surface of the tip of the outrigger box 21 via a bracket 24 as a unit. As shown in detail in FIG. 1, the bracket 24
A rib member 24a provided vertically on the top surface of the front end portion of the outrigger box 21 in the longitudinal direction of the outrigger box 21, and the rib member 24a is rotated by 90 degrees in plan view to move from the vehicle body to the rib member 24a. The support member 24b is formed of a welded flat plate, and a shelf member 24c is provided horizontally at the upper end of the support member 24b toward the vehicle body. 1 and 2, the left hand is the vehicle body side and the right hand is the outrigger jack side as viewed in the drawings.

A circular through hole is formed in the upper wall of the outrigger box 21 and on the vehicle body side near the bracket 24. A sweeper 41 having a cylindrical shape is fitted into the through hole, and the bottom surface of the sweeper 41 is
Is in contact with the upper surface of the Inside the sweeper 41,
A two-stage cylindrical space is formed, and a cylindrical space penetrating in a vertical direction and a cylindrical space serving as a seat for holding a spring described later are formed at the upper end with a step. The detection section 44b of the limit switch 44, which is a detection switch, is passed through the through-column space.

The limit switch 44 is screwed to a switch base 45.
5, a lower guide 43 having a rectangular shape and a circular hole substantially at the center is provided with a limit switch 4
It is attached through the four detectors 44b. An upper guide 46 having the same shape as the lower guide 43 but having no circular hole is attached to the upper end surface of the switch base 45. That is, the limit switch 44 is disposed so as to be surrounded by the switch base 45 and the upper and lower guides 43 and 46 in a “U” shape.

A spring 42 is disposed below the limit switch 44, between the lower surface of the lower guide 43, and a spring seat (the upper end cylindrical space) provided at the upper end of the sweeper 41. The detection unit 44b of the limit switch 44 is provided through the inside and the inside of the sweeper 41. In this way, the limit switch 44 is fixedly mounted on the switch base 45 and the upper and lower guides 43 and 46, but is not restricted by the other components, and is disposed floating on the spring 42. You.

Above the limit switch 44, the shelf member 24c of the bracket 24 is provided with a screw hole in the vertical direction. In this screw hole, as height adjusting means described in the claims, Bolt 4 via nut 47
8 are passed through. By rotating the bolt 48 clockwise, the bolt 48 is lowered with respect to the shelf member 24c, the upper guide 46 is pressed down, the position of the limit switch 44 is lowered, and the detection unit 44b of the limit switch 44 is moved to the upper surface of the outrigger beam 22. Adjustment of the position of the limit switch 44 is performed so that the contact is appropriately made. With the lowering of the limit switch 44, an elastic force is generated in the spring 42, and the sweeper 41 which receives the spring 42 below is pressed against the outrigger beam 22. If the nut 47 is tightened after the adjustment, the bolt 48 is locked. Since the height adjusting means is provided in this manner, the effectiveness of the limit switch 44 can be easily adjusted even at the work site.

After this adjustment, the limit switch 44
Switch base 45 on which limit switch 44 is mounted
Are bolted to the bracket 24 and indirectly fixed to the outrigger box 21. Switch base 4
5 is provided with a long hole, so that if the bolt is loosened, the position adjustment of the limit switch 44 in the vertical direction, that is, the degree of effectiveness can be easily readjusted. The detector 40 thus assembled is entirely covered with a detector cover 49 with the support member 24b as a back.

Next, the operation of the jack grounding detector 40 will be described. Prior to the work at height, when the outrigger jack 25 is extended to stabilize the body of the aerial work vehicle 10, the outrigger beam 22 is moved outward of the body 11 with respect to the outrigger box 21 (right side in FIG. 1). What)
Sent. At this time, since the outrigger jack 25 is disposed at the tip of the outrigger beam 22, the tip side is heavy, and the outrigger box 21 and the outrigger beam 22 are located between the inner surface of the upper tip of the outrigger box 21 and the upper surface of the outrigger beam 22. The gap of the fitting tolerance is generated. The detecting portion 44b of the limit switch 44 of the jack grounding detector 40 receives no pressing force from the upper surface of the outrigger beam 22 or is separated from the upper surface of the outrigger beam 22 by the amount of this gap, and thus is "OFF".

At this time, since the sweeper 41 is urged downward by the spring 42, the sweeper 41 is always strongly pressed against the upper surface of the outrigger beam 22 and relatively slides on the upper surface of the outrigger beam 22. become. For this reason,
When the outrigger jack 25 is overhanging, the upper surface of the outrigger beam 22 and the detector 44 of the limit switch 44
The abutting portion b is cleaned by the lower edge of the sweeper 41. Even if solidified mud or ice adheres to the upper surface of the outrigger beam 22, it is crushed by the lower edge of the sweeper 41 and removed to the side. In addition, since the sweeper 41 surrounds the detection portion 44b of the limit switch 44 over the entire circumference in the lateral direction, foreign matter such as crushed mud does not enter the sweeper 41, and is located on the upper surface of the outrigger beam 22. The attached foreign matter does not hinder the operation of the limit switch 44.

Thus, the outrigger jack 25
Is extended by a predetermined amount, the inner post 27 is extended from the outer post 26 of the outrigger jack 25 to lift the vehicle body 11. When the ground plate 28 descends with the extension of the inner post 27 and the ground plate 28 touches the ground, a drag acts on the outrigger jack 25 as a reaction to the pressing force of the jack cylinder (not shown) pressing the ground. As a result, the outrigger jack 25 itself is lifted. For this reason, the ground plate 28
The gap between the inner surface of the upper end of the outrigger box 21 and the upper surface of the outrigger beam 22 before the outrigger box 25 is lifted by the outrigger jack 25
Disappears as the tip side of the is lifted.

Due to the relative rise of the outrigger beam 22 with respect to the outrigger box 21, the sweeper 41 slides upward with respect to the outrigger box 21, and the limit switch 4 located inside the
The detection unit 44b of No. 4 is also pushed by the upper surface of the outrigger beam 22, the limit switch 44 is turned “ON”, and the grounding of the outrigger jack 25 is detected.

When the outrigger jack 25 is contracted and the vehicle body 11 is lowered and the outrigger jack 25 is retracted, the jack grounding detector 40 operates in the reverse direction of the above description. After the body 11 descends as the outrigger jack 25 shrinks, the outrigger beam 22 descends and the sweeper 41 moves outrigger box 2
1 and the detector 44b of the limit switch 44 is released, and the limit switch 4
4 becomes "OFF". When the outrigger beam 22 is stored in the outrigger box 21, the sweeper 41 relatively slides outward on the upper surface of the outrigger beam 22, so that soil and dust accumulated on the upper surface of the outrigger beam 22 during work are removed by the outrigger. It is paid out of the box 21.

In the present embodiment, the present invention is applied to an aerial work vehicle. However, the present invention is not limited to an aerial work vehicle, but may be applied to a work vehicle having a jack device such as a crane truck. It is equally applicable to this. Further, the present invention is not limited to the above embodiment. In this embodiment,
Although the sweeper 41 is formed in a cylindrical shape, the present invention is not limited to this shape. For example, the outer shape is formed as a square pole, and the diagonal line is oriented in the longitudinal direction with the through hole in the upper wall of the outrigger box 21 into which the sweeper is inserted. If it is formed in a rectangular shape, the quadrangular prism sweeper slides on the upper surface of the outrigger beam 22 so as to separate the adhering matter at the corners, which is more preferable for removing foreign matter.

In this embodiment, a bracket 24 is provided so that the height of the limit switch 44 can be easily adjusted, and the limit switch 44 is pressed down by a bolt 48 from a shelf member 24c of the bracket 24. Has become. For this reason, the configuration is complicated. However, if the limit switch is provided with a flange to hold the spring by this flange and to attach it to the outrigger box, the configuration becomes simple. In this case, a washer may be sandwiched under the flange for height adjustment. Thus, it is apparent that further improvements, improvements, modifications, and the like can be made within the scope of the claims of the present invention.

[0033]

As described above, according to the jack grounding detector of the present invention, when the outrigger beam slides with respect to the outrigger box in order to protrude or be stored in the outrigger box, the outrigger beam is moved. The sweeper slidable up and down with respect to the box is always pressed against the outrigger beam by the urging means and relatively slides on the outrigger beam while surrounding the detection section of the detection switch. Therefore, the foreign matter adhering to the outrigger beam is removed by the sweeper, and does not hinder the detection unit of the detection switch. Even foreign substances such as mud and ice that have adhered to the outrigger beam and solidified are contained in the sweeper because when the outrigger beam is sent, the sweeper crushes and is removed from the orbit of the sweeper, The detection unit of the detection switch does not receive any obstacle from foreign matter. Since the detection unit is protected by the sweeper as described above, the jack grounding detector of the present invention is not only advantageous in terms of maintenance but also excellent in terms of safety of the working vehicle.

Further, in the present invention, since the sweeper is disposed so as to surround the detection portion of the detection switch, it is not necessary to dispose a strip-shaped sweeper on the upper surface of the tip of the outrigger box as in the related art. For this reason, when the outrigger jack device is stored, there is no possibility that the upper end of the outrigger box will interfere with the oil supply hose to the hydraulic control valve that controls the jack cylinder when the outrigger beam is fully contracted.

Further, when height adjusting means for adjusting the vertical position of the detection switch with respect to the outrigger box is provided, the degree of contact between the detection portion of the detection switch and the outrigger beam sliding in the outrigger box is provided. Can be adjusted, and the sensitivity of the jack grounding detector can be easily adjusted.

[Brief description of the drawings]

FIG. 1 is a side view of a jack grounding detector of the present invention.

FIG. 2 is a front view of an outrigger jack device provided with the jack grounding detector of the present invention.

FIG. 3 is an overall side view of the aerial work vehicle according to the present invention.

FIG. 4 is a front view of a conventional outrigger jack device.

[Explanation of symbols]

 Reference Signs List 10 aerial work vehicle 11 body 12 turning table 13 boom 20 outrigger jack device 21 outrigger box 22 outrigger beam 40 jack ground detector 41 sweeper 42 spring 44 limit switch

──────────────────────────────────────────────────の Continuation of the front page (51) Int.Cl. ⁶ identification symbol FI B66F 11/04 B66F 11/04 (58) Field surveyed (Int.Cl. ⁶ , DB name) B66F 9/00-11/04 B66C 23/00-23/94 B60S 9/12

Claims (2)

(57) [Claims] 1. An outrigger box extending in a lateral direction of a vehicle body, an outrigger beam slidably disposed in the outrigger box and capable of projecting to the side of the vehicle body, and a tip end of the outrigger beam. And a jack grounding detector used in a jack device having an outrigger jack that can be extended and contracted downward to lift and support the vehicle body, wherein the jack grounding detector is attached to the outrigger box, and a detection unit is attached to the outrigger beam. A detection switch that is in contact with and detects a vertical displacement of the outrigger beam with respect to the outrigger box; and a sweeper that surrounds the detection unit of the detection switch and is slidably disposed in a vertical direction with respect to the outrigger box. , Disposed between the sweeper and the detection switch,
And a biasing means for pressing the sweeper against the outrigger beam. 2. The jack grounding detector according to claim 1, further comprising height adjusting means for adjusting the position of the detection switch in the vertical direction with respect to the outrigger box.