JPH0125098Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a lateral movement device for a truck crane.

With the recent trend towards larger truck cranes, there are problems in moving them around narrow construction sites.

In order to solve this problem, conventionally, a pair of left and right outrigger beams, which are extendably housed in an outrigger box provided in the body frame of a truck crane, is operated to simultaneously extend and retract a pair of outrigger extension cylinders. It has been proposed to allow a truck crane to move laterally by extending one and retracting the other. However, during this lateral movement, the lower inner end of the outrigger beam and the upper open end of the outrigger box come into contact with the inner surface of the box and the outer surface of the beam, respectively, and the load of the truck crane acts on these contact areas.
Since the sliding friction resistance between the outrigger box and the outrigger beam is quite large, lateral movement cannot be performed smoothly, and a large and powerful cylinder for extending the outrigger is required.

This invention was proposed to eliminate the above-mentioned problems and improve the lateral movement performance of truck cranes in narrow spaces as well as the lifting capacity. The outrigger beam can be contacted only when the outrigger beam is extended or contracted. As a result, the sliding friction resistance between the outrigger beam and the outrigger box is significantly reduced when the outrigger beam is extended or retracted, smoothing the lateral movement, and making it possible to downsize the outrigger extension cylinder. Furthermore, during crane work, the outrigger beam and the outrigger box are brought into surface contact without intervening rollers, so that large loads can be withstood and lifting capacity is improved.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

In FIG. 1, which schematically shows the rear view of a truck crane, 1 is a rear outrigger provided behind the rear wheels 2, and an outrigger box 4 is attached to the vehicle body frame 3, and an outrigger box 4 is stored in the box so as to be extendable and retractable. A pair of left and right outrigger beams 5 and 6, and a pair of outrigger extension cylinders that extend and contract to expand and contract the beams (in order to simplify the drawing, only the cylinder 7 combined with the beam 5 is shown in Figure 1). consists of Jacks 8 and 9 are attached to the outer ends of the beams 5 and 6, respectively.

As shown in detail in FIG. 2, in the embodiment of the present invention, a first roller 11 is pivotally supported at the lower inner end of the left outrigger beam 5 via a bracket 10 and a V-shaped arm 19. , can roll on the inner lower surface of the outrigger box 4. In addition, a bracket 13 is attached to the angle member 12, which is a strength member on the vehicle body side and extends to the side surface of the vehicle body frame 3 and is fixed to the upper part of the opening end of the outrigger box 4. A second roller 14 is pivotally supported via a V-shaped arm 22 near the upper end and can roll on the upper surface of the outrigger beam 5.

The first roller 11 is pivotally supported on one end of a substantially V-shaped arm 19, and the center part of the arm 19 is pivotally connected to the lower part of the flange 10 via a pivot 20, and the other end of the arm is connected to the upper part of the flange. Hydraulic cylinder 2 between
1 is pivoted. Similarly, the second roller 14 is pivoted to one end of the substantially V-shaped arm 22, with the central portion of the arm 22 pivoted to the lower part of the flange 13.
3, and a hydraulic cylinder 24 is pivotally connected between the other end of the arm and the upper part of the flange.

The first roller 11 and arm 19 form a first roller moving device 30, and the second roller 14 and arm 22 form a second roller moving device 31.

Regarding the right outrigger beam 6,
Similarly to the above, a first roller moving device 30 and a second roller moving device 31 are provided.

Although not shown in the drawings, a front outrigger having the same structure as the rear outrigger described above is attached to the vehicle body frame 3 between the front wheels and the rear wheels 2.

Figures 3a and 3b show the lateral movement mode of the truck crane. In Figure 3a, the left outrigger beam 5 is extended and the right outrigger beam 6 is extended.
shows a contracted state. From this state, the cylinder (not shown) for the beam 6 is extended and at the same time the cylinder 7 for the beam 5 is contracted, so that the beam 6 is extended, the beam 5 is contracted, and the truck crane is moved to the third position. It will be moved to the left to the position shown in Figure b. In addition,
In the figure, L ₁ and L ₂ indicate the distance between the truck crane's body center line and the tip of the right outrigger beam 6,
The difference L ₂ −L ₁ is the amount of movement of the truck crane.

According to the above-mentioned embodiment of the present invention, when the outrigger beams 5 and 6 are expanded and contracted during lateral movement of the truck crane, hydraulic pressure is supplied to and from the hydraulic cylinders 21 and 24 from the hydraulic circuit that supplies and discharges the hydraulic pressure to, for example, the outrigger extension cylinder 7. The first roller 11 and the second roller 14 are brought into contact with the outrigger box 4 and the outrigger beams 5 and 6, so that the beam can smoothly slide against the box. can. On the other hand, during crane work, the hydraulic cylinders 21 and 24 have their hydraulic pressure discharged and contract, separating the first roller 11 and the second roller 14 from the outrigger box 4 and the outrigger beams 5 and 6. The inner upper surface of the box comes into contact with the inner lower surface of the box and the upper surface of the beam, respectively, and the areas of these contact surfaces are further increased, making it possible to reduce the surface pressure. This improves the crane's lifting ability and its durability.

Fig. 4 shows a hydraulic circuit that controls the operation of the outrigger extension cylinders of the front and rear outriggers, where 7 is the left rear cylinder, 7' is the right rear cylinder, 7'' is the left front cylinder, 7 is the right front cylinder, 25 is the tank, 26 is the pump, 27
27 are solenoid-operated control valves that control supply and discharge of hydraulic pressure to the cylinders 7 to 7, respectively, and each control valve has an extended position A, a neutral position B, a contracted position C, and a floating position D. In this floating position D, hydraulic pressure can be freely supplied to and discharged from the chambers on both sides of each cylinder.

In FIG. 4, the hydraulic circuit is in a state where the front and rear outriggers are stopped at the positions shown in FIG. 3b. To move the truck crane laterally to the position shown in FIG. 3a, control valves 27' and 27 are placed in floating position D and control valves 27 and 27'' are placed in extended position A.

By providing each control valve with a floating position D, when some control valves are placed in the extended position A and others in the retracted position C during lateral movement, this operation does not have to be performed in precise synchronization. However, the switching operations of the control valves do not necessarily have to be synchronized, which improves operability.

[Brief explanation of the drawing]

Fig. 1 is a schematic rear view of a truck crane showing an embodiment of the lateral movement device according to the present invention;
The figure is an enlarged sectional view showing the main part of Figure 1, Figure 3a is a rear view showing the left outrigger beam extended, and Figure 3b is the right outrigger beam extended to move the truck crane laterally. A rear view showing the moved state, and FIG. 4 is a hydraulic circuit diagram. 1...Rear outrigger, 3...Vehicle frame,
4... Outrigger box, 5, 6... Outrigger beam, 7... Outrigger extension cylinder,
10, 13...Bracket, 11...1st column,
14...Second roller, 19,22...Arm, 2
1, 24... Hydraulic cylinder, 30... First roller moving device, 31... Second roller moving device.

Claims (1)

[Scope of utility model registration request] At least one outrigger is provided which extends and contracts left and right within an outrigger box disposed on the vehicle body frame so as to extend in the vehicle width direction, and has a pair of outrigger beams provided close to each other. In a vehicle in which a jack for lifting the vehicle body is attached to the outer end in the vehicle width direction, an extending cylinder for causing the outrigger beam to expand and contract in the left and right directions is provided within the outrigger box, and can come into contact with the inner lower surface of the outrigger box. A first roller is provided on the inner end of the outrigger beam in the vehicle width direction, and a second roller that can come into contact with the upper surface of the outrigger beam is provided on the vehicle body frame near the outer upper end of the outrigger box in the vehicle width direction. Provided on the vehicle body side strength member such as a box or bracket, and further
A lateral movement device for a truck crane, characterized in that a roller moving device is provided for moving a roller and a second roller to the abutment possible position only when the outrigger beam is extended or contracted.