JP6911637B2 - Work vehicle - Google Patents

Description

The present invention relates to a work vehicle such as a mobile crane or an aerial work platform.

Conventionally, work vehicles such as mobile cranes and aerial work platforms have booms that can be swiveled, expanded and contracted, and undulated. For example, a rotatable sheave provided in the boom head is attached to the tip of the boom of a mobile crane, and a hanging wire to which a hook block is attached is hung on the tip of the sheave (patented). Reference 1).

Japanese Unexamined Patent Publication No. 9-301682

In the conventional work vehicle, the boom protrudes in front of the work vehicle even when the boom is retracted and retracted, and the driver is obstructed by the boom head when the work vehicle is running. In addition, since the ground clearance (minimum ground clearance) in the retracted state of the hook becomes low, there is a problem that the approach angle (slope approach angle) and departure angle (slope exit angle) during traveling become small.

The present invention has been made in view of such conventional problems, and an object of the present invention is to provide a work vehicle having a large approach angle and departure angle without obstructing the driver's field of view during traveling.

In order to achieve the above object, the work vehicle of the present invention is
The first boom and
Boom head and
Suspended wire and
It is a crane equipped with
The vicinity of the lower tip of the first boom and the vicinity of the lower rear end of the boom head are fixed.
The boom head is characterized in that it is rotatably provided around a fixed portion with the first boom on a rotation axis parallel to the rotation axis of the undulating operation of the first boom.

It is possible to provide a work vehicle having a large approach angle and departure angle without obstructing the driver's field of view during traveling.

It is an example of the side view of the crane which concerns on this embodiment. It is an example of the schematic block diagram around the boom head of the crane which concerns on this embodiment. It is another example of the schematic block diagram around the boom head of the crane which concerns on this embodiment. It is a figure for demonstrating the problem of the conventional crane. It is a figure for demonstrating an example of the effect of the crane which concerns on this embodiment.

Hereinafter, an embodiment according to the present invention will be described with reference to the drawings. However, the components described in the following embodiments are examples, and the technical scope of the present invention is not limited to them.

Examples of the work vehicle according to the present embodiment include mobile cranes, and specific examples thereof include rough terrain cranes, all terrain cranes, truck cranes, and loaded truck cranes. Hereinafter, a rough terrain crane (hereinafter, simply referred to as a crane) will be described as an example of the work vehicle according to the present embodiment.

(Outline configuration of crane)
First, the outline overall configuration of the crane as a work vehicle according to the present embodiment will be described with reference to FIG. FIG. 1 shows an example of a side view of the crane according to the present embodiment. As shown in FIG. 1, the crane 1 according to the present embodiment is horizontal to the vehicle body 10, the vehicle body 10 which is the main body portion of the vehicle having a traveling function, the outriggers 11 provided at the four corners of the vehicle body 10, ... It includes a swing table 12 that is rotatably attached, and a boom 14 that is attached to a bracket 13 that is erected on the swing table 12.

The out-trigger 11 can slide out / slide outward from the vehicle body 10 in the width direction by expanding / contracting the slide cylinder, and can extend / jack retract in the vertical direction from the vehicle body 10 by expanding / contracting the jack cylinder. Is.

The swivel base 12 has a pinion gear to which the power of the swivel motor is transmitted, and the pinion gear meshes with a circular gear provided on the vehicle body 10 to rotate around the swivel shaft. The swivel base 12 has a cockpit 18 arranged on the front right side, a bracket 13 arranged in the rear center, and a counterweight 19 arranged in the rear lower part.

The boom 14 has, for example, a three-stage boom configuration that is nested by a base end side boom 14a, an intermediate boom 14b, and a tip end side boom 14c. The base end side boom 14a, the intermediate boom 14b, and the tip side boom 14c are usually configured in a nested manner in which the base end side boom 14a is arranged on the outermost side and the tip end side boom 14c is arranged on the innermost side.

The base end side boom 14a is rotatably attached to a support shaft whose base portion is horizontally installed on the bracket 13, and can be undulated up and down with the support shaft as the center of rotation. Further, an undulating cylinder 15 is bridged between the bracket 13 and the lower surface of the base end side boom 14a, and the entire boom 14 can be undulated by expanding and contracting the undulating cylinder 15.

A boom head 40 according to the present embodiment, which will be described later, is attached to the tip of the tip side boom 14c, and a hook block 17 (hereinafter referred to as a hook 17) is attached to the tip side of the boom head 40. The suspended load wire 16 (hereinafter referred to as wire 16) is hung. On the other hand, the end of the wire 16 is wound around a winch (not shown), and the wire 16 and the hook 17 can be wound or unwound by rotating the winch.

Further, in the rough terrain crane 1 according to the present embodiment, the jib 30 and the tension rod 20 are stored in a lateral holding posture on the side surface of the base end side boom 14a. The jib 30 and tension rod 20 are mounted / retracted using a plurality of pins (not shown) and side-up cylinders (not shown).

(Detailed configuration example around the boom head)
Next, a detailed configuration example around the boom head 40 of the crane 1 according to the present embodiment described with reference to FIG. 1 will be described with reference to FIG. FIG. 2 shows an example of a schematic configuration diagram of the boom head 40 of the crane according to the present embodiment. The states of the boom 14 and the boom head 40 shown in FIG. 2 indicate a state when the boom is extended, for example, when working.

In the boom head 40 according to the present embodiment, the vicinity of the lower part of the rear end and the vicinity of the lower part of the tip of the front end side boom 14c are fixed by the fixing means 50. Further, the tip-side boom 14c and the boom head 40 are connected via, for example, a link 60 that is bent in two or more stages. By connecting and fixing the boom head 40 and the tip-side boom 14c as described above, the boom head 40 can rotate around the fixing means 50. In the fixing of the tip end side boom 14c and the boom head 40 by the fixing means 50, the rotation axis of the rotation of the boom head 40 with respect to the boom 14 is parallel to the rotation axis of the undulating operation of the base end side boom 14a described above. To be.

A first sheave 70 is provided in the vicinity of the upper end of the tip side boom 14c. A second sheave 80a is provided in the boom head 40. In the crane 1 having the above configuration, the wire 16 is hung from a winch (not shown), the first sheave 70 and the second sheave 80a are hung in this order, and the wire 16 is connected to the main hook 17a at the tip of the wire 16. do.

Further, as shown in FIG. 2, when the sub hook 17b is provided, a third sheave 80b is further provided in the boom head 40, the wire 16 is fed out from a winch (not shown), and the first sheave 70 and the third sheave are provided. It is hung in the order of 80b and connected to the sub hook 17b at the tip of the wire 16.

(Expansion and contraction of the boom accompanied by the rotation operation of the boom head)
Next, an example of the rotation operation of the boom head 40 according to the present embodiment will be described with reference to FIG. FIG. 3 shows another example of a schematic configuration diagram around the boom head of the crane according to the present embodiment. The states of the boom 14 and the boom head 40 shown in FIG. 3 indicate a state when the boom is fully contracted, for example, when the crane 1 is traveling.

From the state of the boom head 40 shown in FIG. 2, first, the boom 14 is fully contracted. Then, the wire 16 is wound up using a winch (not shown) to bring the main hook 17a into contact with the boom head 40.

In this state, when the wire 16 is further wound up, the boom head 40 is rotated (raised up) by the winding force. Then, by further winding the wire 16, the boom head 40 is housed inside the tip-side boom 14c by the winding force, as shown in FIG.

On the other hand, when shifting from the state of the boom 14 and the boom head 40 shown in FIG. 3 to the state of the boom 14 and the boom head 40 shown in FIG. 2, the boom 14 is extended while winding down the wire 16. Then, by further winding down the wire 16, the boom head 40 can be rotated, so that the boom head 40 can be projected to the front surface of the boom 14 as shown in FIG.

(effect)
Next, the features of the boom head 40 according to the present embodiment with respect to the conventional boom head will be described with reference to FIGS. 4 and 5.

FIG. 4 shows a diagram for explaining the problems of the conventional crane, and FIG. 5 shows a diagram for explaining an example of the effect of the crane according to the present embodiment. Both the cranes shown in FIGS. 4 and 5 show the state when the boom is fully contracted (for example, when traveling).

In the conventional crane shown in FIG. 4, the boom head 140 is not fixed or connected to the tip end side boom 14c via the fixing means 50 and the link 60, and has a rotation axis parallel to the rotation axis of the undulating operation of the boom. It differs from the boom head 40 according to the present embodiment in that it cannot rotate. In FIG. 4, the main hook 17a, the sub hook 17b, the first sheave 70, the second sheave 80a, and the third sheave 80b according to the present embodiment have the same functions as the main hook. Reference numerals are given to 117a, a sub-hook 117b, a first sheave 170, a second sheave 180a, and a third sheave 180b.

In a conventional crane, when the boom is fully contracted, the boom head 140 projects forward of the boom 14, and the portion accommodating the second sheave 180a and the third sheave 180b is larger than the lower end of the boom 14. It overhanged downward. Therefore, as shown by the arrow in FIG. 4, the field of view of the crane driver P is obstructed by the boom head 140, which may lead to an accident. In addition, since the ground clearance (minimum ground clearance) during traveling becomes low, there is a problem that the approach angle (slope approach angle) and departure angle (slope exit angle) become small.

On the other hand, in the crane according to the present embodiment, since the boom head 40 can rotate on a rotation axis parallel to the rotation axis of the undulating operation of the boom 14, the boom head 40 and the hook 17 are boomed when the boom is fully contracted. Do not overhang below the lower end of 14. Further, since the boom head 40 can be housed inside the intermediate boom 14b together with the front end side boom 14c, the total length of the boom 14 and the boom head 40 can be shortened.

Therefore, the field of view of the crane driver P is not obstructed by the boom head 140, and the stability is improved. In addition, the approach angle (slope approach angle) and departure angle (slope exit angle) can be increased.

1: Rough terrain crane;
10: Body 11: Outrigger 12: Swing table 14a: Base end side boom 14b: Intermediate boom 14c: Tip side boom 15: Undulating cylinder 16: Wire 17a: Main hook 17b: Sub hook 20: Tension rod 30: Jib 31: Side up Cylinder 40: Boom head 50: Fixing means 60: Link 70: First sheave 80a: Second sheave 80b: Third sheave

Claims (2)

The first boom and
Boom head and
Suspended wire and
It is a crane equipped with
The vicinity of the lower tip of the first boom and the vicinity of the lower rear end of the boom head are fixed.
The boom head about a fixed point between the first boom, pivotally provided et al is a rotary shaft and a rotational axis parallel undulating motion of the first boom,
The first boom and the boom head are further connected via a link.
A first sheave is provided near the upper part of the tip of the first boom.
A second sheave is provided in the boom head.
The hanging wire is hung on the first sheave and the second sheave.
The boom head is rotatably provided by hoisting and lowering the suspended load wire.
Work vehicle. The first boom and
Boom head and
Suspended wire and
It is a crane equipped with
The vicinity of the lower tip of the first boom and the vicinity of the lower rear end of the boom head are fixed.
The boom head is rotatably provided around a fixed portion with the first boom on a rotation axis parallel to the rotation axis of the undulating operation of the first boom.
The crane further has a second boom closer to the proximal end than the first boom.
The first boom and the boom head are configured to be retractable in the second boom.
Work vehicle.

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