JPH0572887U - Multi-stage boom - Google Patents

Abstract

(57) [Summary] [Purpose] Since multiple members are not fixed by welding, deburring and strain removal due to welding are not required, and weight reduction can be achieved and fabrication is easy.
It also offers a multi-tiered boom that is aesthetically pleasing. [Structure] In a multi-stage boom 15 in which a plurality of booms 15a to 15e are configured to extend and contract, the multi-stage boom 15
At least one boom of the plurality of booms constituting the above is formed by plastic working.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 INDUSTRIAL APPLICABILITY The present invention relates to a multi-stage boom, and is used as a boom for a truck-mounted crane, for example.

[0002]

[Prior Art]

 Conventionally, for example, each boom constituting a multi-stage boom in a truck-mounted crane has, as shown in FIG. 4, two flat steel plates a and a and two left and right steel plates whose side edges are hook-shaped. The steel plates b and b were combined, and the steel plates a and b were welded and fixed together to form a rectangular cross section.

[0003]

[Problems to be solved by the device]

 However, in the case where a boom is produced by welding by combining a plurality of steel plates as in the above-mentioned conventional method, it is necessary to remove burrs and strains due to welding, which requires time and labor for production, and is unaesthetic There were problems such as being heavy.

[0004]

[Means for Solving the Problems]

 The multi-stage boom of the present invention is a multi-stage boom in which a plurality of booms are configured to extend and retract, and at least one boom among the plurality of booms forming the multi-stage boom is formed by plastic working. ..

[0005]

[Action]

 By forming at least one boom among the plurality of booms constituting the multi-stage boom by plastic working, the work by welding is eliminated and the work such as deburring and strain removal due to the welding is eliminated.

[0006]

【Example】

 An embodiment of the present invention will be described below with reference to the drawings. In this example, a truck-mounted crane will be described as an example of a multi-stage boom.

FIG. 1 shows a schematic configuration of a truck-mounted crane.

In FIG. 1, reference numeral 1 denotes a truck-mounted crane mounted on the body of a truck (not shown), which is fixed between a driver's seat (not shown) and a luggage box.

The truck-mounted crane 1 includes a support frame 11, a swivel base 12 rotatably provided on the support frame 11, a swivel post 13 standing on the swivel base 12, and the swivel post 13. It is composed of a multi-stage boom 15 pivotally supported by.

The multi-stage boom 15 includes a base end boom 15a, a first intermediate boom 15b that is telescopically inserted into the base end boom 15a, and a first intermediate boom 15b that is telescopically inserted into the first intermediate boom 15b. 2 intermediate boom 15c, a third intermediate boom 15d telescopically inserted into the second intermediate boom 15c, and a tip boom 15e telescopically inserted into the third intermediate boom 15d. The first to third intermediate booms 15b, 15c, 15d and the tip boom 15e are telescopically operated by the telescopic operation of a plurality of built-in telescopic cylinders (not shown) that are of a stepped telescopic type, and at the same time as the base end boom 15a. A hoisting cylinder 14 connected to the swivel post is configured to be hoistable.

In the multi-stage boom 15, for example, the tip boom 15e is formed in a rectangular cross section by plastic working such as extrusion or drawing of a steel pipe, as shown in FIG. By forming the tip boom 15e from the copper pipe by plastic working as described above, a plurality of members are not fixed by welding as in the conventional case, and deburring and strain removal due to welding are unnecessary.

Not only the tip boom 15e but also the base boom 15a and the first to third intermediate booms 15b to 15d may be formed by plastic working as described above.

The turning post 13 is configured to be turned by a turning motor (not shown).

A winch device (not shown) is provided at the base end of the multi-stage boom 15. A winch motor (not shown) winds a wire 17 continuous with a hook 16 suspended from the tip boom 15e. It is configured to pick up or pay out.

Inside the support frame 11, an outrigger (not shown) having a jack device 18 fixedly mounted at its tip is fitted to both sides of the vehicle body in a freely projecting manner.

Further, on both the left and right sides of the support frame 11, a plurality of operating levers 21 for operating the actuators such as the telescopic cylinder, the undulating cylinder 14, the swing motor, and the winch motor are provided. Is provided.

In this example, the boom having a rectangular cross section formed by plastic working has been described, but the cross sectional shape of the boom (eg, the tip boom 15e) is not limited to this, and an octagonal shape as shown in FIG. 3 is used. Other polygons may be formed. In this case, since the boom is formed by plastic processing, it is possible to easily form a complicated shape such as a polygon.

Further, in this example, the boom of the truck-mounted crane is described as an example of the multi-stage boom, but the multi-stage boom is not limited to this, and is also applicable to other booms such as booms for aerial work vehicles, etc. Can be used.

[0019]

[Effect of the device]

 As described above, according to the present invention, at least one of the plurality of booms forming the multi-stage boom is formed by plastic working, so that a plurality of members are fixed by welding as in the past. This eliminates the need for removing burrs and strains due to welding, reduces weight, facilitates manufacturing, and has a good appearance.

[Brief description of drawings]

FIG. 1 is a side view showing a truck-mounted crane.

FIG. 2 is a sectional view showing a sectional shape of the boom of the present invention.

FIG. 3 is a sectional view showing another sectional shape of the boom of the present invention.

FIG. 4 is a sectional view showing a sectional shape of a conventional boom.

[Explanation of symbols]

 15 Multi-stage boom 15e Tip boom

Claims (1)

[Scope of utility model registration request] 1. A multi-stage boom in which a plurality of booms are extendable and retractable, wherein at least one boom among the plurality of booms forming the multi-stage boom is formed by plastic working. ..