JPH08208186A - Outrigger unit of truck crane - Google Patents

Abstract

PURPOSE: To shorten the length of a chord conforming to an angle variation in a jack by attaching a bracket tight to the tip of a piston rod, situating each edge at both sides extending beneath the bracket so as to be adjoined to the circumferential surface of a cylinder in a state of contraction in the jack, and pivotally supporting each of the edges at both the sides with a pivot. CONSTITUTION: A pivotal part 15 with two separate brackets 17a and 17b is installed in a crane base 4a, and a proximate side jack 6b is pivoted to these brackets 17a and 17b of this pivotal part 15. This proximate side jack 6b is set up as setting a piston rod 22 upside and a cylinder 21 downside, respectively. In addition, a U-shaped bracket 23 is attached tight to a tip part of this piston rod 22 as being opened beneath, while two edge parts 23a and 23b extending beneath the bracket 23 are situated so as to be adjoined to a circumferential surface of the cylinder 21 in a state of contraction in the jack 6b, and these edge parts 23a and 23b are pivoted by two pivots 24a and 24b. With this constitution, length in a chord conforming to an angle variation in the proximate side jack 6b can be shortened as specified.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an outrigger device for a mobile crane.

[0002]

2. Description of the Related Art Conventionally, there is a crane vehicle in which a crane is mounted on the bed of a commercially available truck.

In this type of mobile crane, an outrigger device is attached to the truck in order to ensure stability when hanging by the crane, and a through hole is formed in the floor plate of the cargo bed to penetrate it. An outrigger device is constructed by arranging a jack at the top and attaching the upper end to the base of the crane.

Since the stability of the crane vehicle obtained by the outrigger device is influenced by the amount of overhang of the outrigger device to the vehicle side, a certain amount of overhang is secured in the crane vehicle having the above outrigger device. Therefore, there is a case where the jack of the outrigger device is installed in a state where it is overhanging at an angle.In the overhanging operation of the jack, the overhanging direction is tilted to a greater extent by rotationally displacing the jack around the attachment position during the operation. There is something.

In this case, in order to install the outrigger device so as to penetrate the floor plate, a long hole-like through hole is formed in the floor plate according to the change in the posture of the jack.

[0006]

When the through hole formed in the floor plate of the cargo bed is particularly elongated, the through hole reduces the rigidity of the vehicle body, and therefore the through hole should be as small as possible. It is preferable.

The present invention has been made in view of the above circumstances, and in this type of mobile crane, it is formed on the floor plate of the luggage carrier along with the installation of the outrigger device without reducing the expansion and contraction amount of the jack of the outrigger device. The purpose of the invention is to reduce the size of the through-holes and reduce the decrease in the rigidity of the crane vehicle.

[0008]

In order to achieve this object, the invention as set forth in claim 1 is an upper part of a jack composed of a telescopic cylinder which constitutes an outrigger device on a base of a crane mounted on a bed of a truck. Is pivotally supported by a pivot, and the lower part of the jack is extended below the loading platform through a through hole formed in the floor plate of the loading platform, and the jack is adapted to change its inclination in accordance with its extension and contraction. In the outrigger device, the jack is arranged with its piston rod on the upper side and its cylinder on the lower side, and a U-shaped bracket is fixed to the tip end of the piston rod in a downward opening and extends below the bracket. The edge portions on both sides are positioned so as to face the peripheral surface of the cylinder in the contracted state of the jack, and the edge portions on both sides are pivotally supported by the pivot shaft. It is an outrigger apparatus of the crane truck to butterflies.

[0009]

According to the first aspect of the invention, a U-shaped bracket is fixed to the tip of the piston rod arranged on the upper side so as to open downward, and the edge portions on both sides extending downward of the bracket are fixed. , When the telescopic cylinder is in the contracted state, it is positioned so as to face the peripheral surface of the cylinder, and the edges on both sides of these are pivotally supported by the base of the crane with a pivot, so that the amount of expansion and contraction of the jack does not decrease, It is possible to bring the pivot point closer to the floor plate of the loading platform than before, and it is possible to shorten the length of the string corresponding to the change in the angle of the jack.

Therefore, the size of the through hole to be formed in the floor plate of the cargo bed can be made small, and the decrease in rigidity of the mobile crane can be reduced.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the embodiments shown in the drawings.

First, referring to FIG. 2 and FIG. 3, the general outline of the crane vehicle will be described. 1 is a crane vehicle and 2 is a vehicle body.

The vehicle body 2 is composed of a commercially available truck and is self-propelled, and a crane 4 is mounted on a loading platform 3 of the vehicle body 2.
Is also the base 4a of the crane 4 installed on the platform 3.
Jacks 6a and 6b constituting the outrigger device 5 are respectively installed at positions on both sides of the vehicle side afterward.

The crane 4 is a simple type crane,
A swivel base (not shown) is provided on a base 4a installed on the loading platform 3 to be swivelable.

The crane 4 has a post 7 erected on the swivel base and a telescopic boom 8 installed on the upper end of the post 7 so that the crane 7 can be lifted and lowered. A wire rope and a hook (not shown) extending from a built-in winch are hung down from the tip portion of the telescopic boom 8 having an appropriate length.

Jacks 6 which are installed on both sides of the base 4a of the crane 4 on the vehicle side and constitute an outrigger device 5 are provided.
Each of a and 6b is composed of a telescopic cylinder which is a hydraulic cylinder. As shown in FIG. 3, the jack 6 on the side far away from the post 7 of the crane 4 is used.
Reference numeral a denotes a jack that extends and contracts in the vertical direction to perform a jacking operation.

On the other hand, with regard to the jack 6b of the crane 4 which is close to the post 7 (hereinafter referred to as "proximity jack"), the proximity jack 6b is extended from the retracted state as will be described later, and finally the outer side. The jack operation is performed so as to extend in a state of being obliquely extended toward the front side. In this embodiment, the present invention is carried out with respect to the near side jack 6b.

FIG. 1 is a sectional view in the vehicle width direction in the vicinity of the near side jack 6b.
The floor plate 12 has a through hole 13 formed in the shape of a long hole that is long in the vehicle width direction in accordance with the jack operation of the near side jack 6b.

A support member 14 having a lower end fixed to the vehicle body frame 11 is inserted through the through hole 13, and a base 4a of the crane 4 is provided above the floor plate 12 and above the support member 14. It is connected and supported.

On the base 4a of the crane 4, the pivot portion 15 of the near side jack 6b and the near side jack 6b are provided.
A guide device 16 for appropriately controlling the inclination posture (inclination angle) of the near-side jack 6b is installed along with expansion and contraction of the.

The pivot portion 15 has two spaced brackets 17a and 17b as shown in FIG.
A near side jack 6b configured as follows is pivotally supported by these brackets 17a and 17b.

That is, the near-side jack 6b is composed of the hydraulic cylinder as described above, and is provided with the cylinder 21 and the piston rod 22, and the cylinder 21 is arranged on the lower side and the piston rod 22 is arranged on the upper side. It takes into consideration the adhesion of mud.

A bracket 23 formed in a U shape is formed at the upper end of the upper portion of the piston rod 22 which slightly protrudes from the opening of the cylinder 21 when the near side jack 6b is in the most contracted state. Is cylinder 21
It is fixed in a state of opening downward toward the side.

Therefore, when the near side jack 6b is contracted with the bracket 23 attached, the edge portions 23a and 23b on both sides of the bracket 23 are in positions facing the upper peripheral surface of the cylinder 21 (FIG. 5). reference).

The edge portions 2 on both sides of the bracket 23 fixed to the piston rod 22 of the near side jack 6b in this manner.
3a and 23b are pivotally supported by the brackets 17a and 17b of the pivot portion 15 via pivot shafts 24a and 24b, respectively.

The pivot shafts 24a and 24b for pivotally supporting the edge portions 23a and 23b on the brackets 17a and 17b of the pivot portion 15 as described above are arranged on the same straight line OO which is generally oriented in the front-rear direction of the mobile crane 1. Has been done. This is because the near-side jack 6b can be tilted toward the vehicle side along the longitudinal direction of the through hole 13.

As shown in FIG. 4, the guide device 16 has an outer cylinder 31 whose upper end is fixed to the base 4a, and a slide member 32 which is vertically slidable inside the outer cylinder 31. Is.

The slide member 32 is formed with a long hole 32a which is long in the axial direction of the outer cylinder 31, and the lower end portion of the slide member 32 is provided with a swingable connecting arm 32b.

In the long hole 32a of the slide member 32,
The slidable range of the slide member 32 is limited by inserting the pin 31a whose both ends are supported by the outer cylinder 31.

The connecting arm 32b has its tip pivotally supported on the cylinder 21, and has the above-mentioned near side jack 6b.
In the latter half of the extending operation and in the first half of the contracting operation of the near side jack 6b, the tilting angle of the near side jack 6b is required due to the rocking of the near side jack 6b as it expands and contracts. To change it.

The proximity jack 6b mounted on the base 4a of the crane 4 operates as follows in accordance with its extension and contraction.

The extension operation of the near side jack 6b in the contracted state will be described. First, the near side jack 6b extends along the outer cylinder 31 of the guide device 16 with the slide member 32 in the inclined position within the range of the elongated hole 32a. Extend.

The pin 3 is placed in the long hole 32a of the slide member 32.
When 1a reaches the upper end portion, the descending of the slide member 32 is stopped at that position, but the extension of the near side jack 6b continues, so that the connecting arm 32b starts swinging, and as a result, the near side jack 6b is pivoted. It is rocked around 24a and 24b, the inclination becomes large toward the vehicle side, and finally, as shown in FIG.
The jack-up is performed in the state shown in. Regarding the near-side jack 6b whose swing angle is changed by swinging in this way, in the through-hole 13 formed so as to correspond to the operation of the near-side jack 6b, in the longitudinal direction of the through-hole 13. The dimension corresponds to the "string" with respect to the angular displacement of the near side jack 6b.

On the contrary, when the near side jack 6b is contracted from the jack-up state, the connecting arm 32b is substantially perpendicular to the slide member 32, and therefore the connecting side arm 6b is first connected when the near side jack 6b is contracted. Arm 32
b is folded in, and accordingly, the near side jack 6
The state of b is along the outer cylinder 31.

Thereafter, when the proximity jack 6b is further contracted, the slide member 32 rises in the range of the elongated hole 32a, and the pin 31a reaches the lower end of the elongated hole 32a to complete the contraction operation and enter the retracted state.

In the near-side jack 6b of this embodiment, by removing the pin 31a of the guide device 16, the near-side jack 6b can be expanded and contracted in a vertical posture without tilting, so-called on-site installation. It is also possible to jack up.

In the near side jack 6b which performs the above-mentioned operation, as shown in FIG.
The pivot point of 24b is from the floor plate 12 to the near side jack 6
It is closer to the dimension B than the dimension A to the upper end of b.

Therefore, when the amount of protrusion of the near side jack 6b is constant, the length of the chord corresponding to the angle becomes shorter accordingly, and the through hole 13 to be formed in the floor plate 12 of the luggage carrier 3 in the longitudinal direction. Is small, and the decrease in rigidity of the mobile crane 1 can be reduced.

Then, in this embodiment, the floor plate 1 of the loading platform 3 is used.
Since the through hole 13 formed in 2 is formed in the immediate vicinity of the crane 4, it is also advantageous in terms of the influence of the vehicle body rigidity on the suspended load of the crane 4 and the like.

Further, in the above-mentioned embodiment, the pivot point is located below the upper end of the near side jack 6b by using the bracket 23 having a U shape, but this allows the amount of expansion and contraction of the near side jack 6b. The pivot point can be lowered without making it smaller.

Further, in this embodiment, since the pivotal portion which is normally installed at the tip of the piston rod 22 is removed and the bracket 23 having the U-shape is fixed, only the dimension of the pivotal portion is provided. The length of the near side jack 6b is shortened. Therefore, when the expansion / contraction amount of the proximity side jack 6b is constant, a large load clearance can be secured below the proximity side jack 6b in the stored state, and when the load clearance is constant, a jack having a correspondingly long expansion / contraction amount is used. It becomes possible to do.

In the above-described embodiment, the case where only the near side jack 6b is carried out has been described, but the present invention is not limited to this, and it may be carried out at the far away jacks 6a, and as the jack expands and contracts. Various types of guide devices may be used for appropriately controlling the inclined posture of the jack.

In the practice of the present invention, depending on the truck used as the vehicle body 2, as shown by the phantom line in FIG. 2, the loading / unloading bracket 35 for the loading platform 3 is installed on the vehicle side near the near side jack 6b. When using such a vehicle body 2, it may be necessary to cut off the lower edge portion of the boarding / alighting bracket 35 because it is necessary to secure an expansion / contraction space for the near side jack 6b.

However, even in such a case, as in the above-described embodiment, by locating the pivot point of the upper portion of the near side jack 6b below the upper end of the jack,
The expansion / contraction space of the near side jack 6b is the bracket 35 for getting on / off
Since it becomes lower in the vicinity of, it is possible to reduce the need to cut off the lower edge of the boarding bracket 35.

[0045]

As described above, according to the first aspect of the present invention, a downwardly opening U-shaped bracket is fixed to the tip end portion of the piston rod arranged on the upper side, and the bracket is provided below the bracket. Position the extending edges on both sides so as to face the peripheral surface of the cylinder when the telescopic cylinder is in the contracted state,
Since the edges on both sides are pivotally supported on the base of the crane by a pivot, the pivot point of the upper part of the jack can be brought close to the floor plate of the loading platform without reducing the expansion and contraction amount of the jack, and the angle of the jack can be changed. The length of the corresponding string can be shortened.

Therefore, the size of the through hole to be formed in the floor plate of the cargo bed can be small, and the decrease in rigidity of the crane vehicle can be reduced.

[Brief description of drawings]

FIG. 1 is an enlarged cross-sectional view of a main part of an outrigger device according to an embodiment.

FIG. 2 is a schematic side view of a mobile crane.

FIG. 3 is a schematic rear view of the mobile crane.

FIG. 4 is a sectional view in which a part of the vicinity of the jack in a contracted state is broken away.

5 is a view on arrow C of FIG. 4. FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Crane vehicle 2 Truck (car body) 3 Bed 4 Crane 4a Base 5 Outrigger device 6b Jack (proximity side jack) 12 Floor plate 13 Through hole 16 Guide device 21 Cylinder 22 Piston rod 23 Bracket 23a, 23b Edge part 24a, 24b Axis

Claims (1)

[Claims] 1. An upper part of a jack made up of a telescopic cylinder that constitutes an outrigger device is pivotally supported by a base of a crane mounted on a bed of a truck, and a lower part of the jack is formed on a floor plate of the bed. An outrigger device for a crane truck, wherein the jack is extended downward through a hole and the inclination is changed according to expansion and contraction of the jack, and the jack is arranged with its piston rod on the upper side and its cylinder on the lower side. Then, a U-shaped bracket is fixed to the tip of the piston rod so as to open downward so that the edges of both sides of the bracket extending downward face the peripheral surface of the cylinder in the contracted state of the jack. An outrigger device for a mobile crane, wherein the outrigger device is positioned and pivotally supports the edges on both sides by the pivot.