JP7025692B2 - Boom head - Google Patents

Description

Application of Article 30, Paragraph 2 of the Patent Act Published in the material "CREVO mini G4" issued by Tadano Limited on October 11, 2017 The material "Tadano Rough Terrain Crane GR" issued by Tadano Limited on October 11, 2017. -Published in "130NL type / GR-130N type (power tilt jib) specifications (provisional version)" Posted on the homepage of Tadano Limited on December 18, 2017 (http://www.tadano.co.jp) /Ir/newsrelease/2017/171218.html)

The present invention relates to a boom head of a mobile crane.

The mobile crane is equipped with a boom that can be swiveled and undulated. A boom head with a plurality of sheaves (pulleys) is attached to the tip of the boom. Conventionally, various configurations of this boom head have been proposed.

For example, in the boom head described in Patent Document 1, the main hook is rotated upward and stored while traveling, and the sub hook is also rotated upward and stored on the side of the main hook. There is.

Japanese Unexamined Patent Publication No. 2004-352470.

However, the conventional boom head including Patent Document 1 is provided with a main hook sheave and a sub hook sheave separately, so that the weight is large.

Therefore, an object of the present invention is to provide a boom head that can be used for both a main hook and a sub hook while achieving weight reduction.

In order to achieve the above object, the boom head of the present invention includes a left side plate and a right side plate arranged facing the tip of the boom, and a plurality of sheaves rotatably supported between the left side plate and the right side plate. A boom head comprising, wherein the sheaves are one upper sheave located in the upper part between the left side plate and the right side plate, and a plurality of lower parts arranged in the lower part between the left side plate and the right side plate. It is composed of only a side sheave, and a pin to which the base end portion of the jib is engaged when attaching the jib is installed through the both side plates on the rear side of the plurality of lower sheaves. There is.

As described above, the boom head of the present invention is a boom head including a left side plate and a right side plate arranged to face the tip of the boom, and a plurality of sheaves rotatably supported between the left side plate and the right side plate. The plurality of sheaves are composed of only one upper sheave arranged at the upper part between the left side plate and the right side plate and a plurality of lower sheaves arranged at the lower part between the left side plate and the right side plate. According to such a configuration, the boom head can be used for both the main hook and the sub hook while achieving weight reduction.

It is a side view of a rough terrain crane. It is a side view of a boom head. It is a front view of a boom head. It is explanatory drawing explaining how to draw out a jib.

Hereinafter, embodiments of 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.

(Constitution)
First, the overall configuration of the rough terrain crane 1 as a mobile crane provided with the boom head 40 of this embodiment will be described with reference to FIG. In the following embodiment, the rough terrain crane 1 will be described as an example of a mobile crane, but the present invention is not limited to this, and is widely applied to other mobile cranes such as cargo cranes, truck cranes, and all terrain cranes. The invention can be applied

(Overall configuration of the crane)
As shown in FIG. 1, the rough terrain crane 1 of the present embodiment includes a vehicle body portion 10 which is a main body portion of a vehicle having a traveling function, outriggers 11 provided at four corners of the vehicle body portion 10, and a vehicle body. A swivel table 12 attached to the section 10 so as to be able to swivel horizontally, and a boom 14 attached to a bracket 13 erected on the swivel table 12 are provided.

The out trigger 11 can be slid out / slide-stored outward in the width direction from the vehicle body 10 by expanding / contracting the slide cylinder, and the jack can be extended / jack-stored in the vertical direction from the vehicle body 10 by expanding / contracting the jack cylinder. It is possible.

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 portion 10 to rotate around the swivel shaft. The swivel table 12 has a driver's cab 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 is nested inside by a multi-stage boom component, such as a proximal boom 141, one to a plurality of intermediate booms 142 (142a to 142d in FIG. 2), and a tip boom 143. It can be expanded and contracted by the telescopic cylinder.

Further, in this embodiment, the jib 50 and the tension rods 60, 60 are housed in the lower hugging posture on the lower surface of the base end boom 141. The jib 50 has a Y-shape as a whole, and the base end side has a bifurcated shape that can be engaged with the boom tip portion. In the retracted posture, the two tension rods 60, 60 are arranged so as to overlap each other on the side of the jib 50.

The outermost base end boom 141 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 boom 141, and the entire boom 14 can be undulated by expanding and contracting the undulating cylinder 15.

(Boom head configuration)
As shown in detail in FIG. 2, a boom head 40 is attached to the tip of the tip boom 143. The boom head 40 has the left side plate 41 and the right side plate 42 arranged to face each other, and the upper side sheave 23 and the lower side sheave 21 as a plurality of sheaves rotatably supported between the left side plate 41 and the right side plate 42. 22 and mainly composed of. Then, on the rear side (base end side) of the lower sheaves 21 and 22, a pin 43 with which the base end portion of the jib 50 is engaged when the jib 50 is attached is installed.

The left side plate 41 and the right side plate 42 are formed by a metal plate in a shape in which the lower portion protrudes like a jaw, and the shafts of the upper sheaves 23 and the lower sheaves 21 and 22 and the pins for the jib 50 are sandwiched between them. 43 are straddled and arranged to face each other so as to be parallel to each other. The pin 43 for the jib 50 penetrates the side plates 41 and 42 and protrudes to the left and right. The pin 43 for the jib 50 and the lower sheaves 21 and 22 are arranged apart from each other at a predetermined distance so that the cable end of the wire rope 16 can be inserted.

The plurality of sheaves of this embodiment are composed of one upper sheave 23 arranged at the upper part and two lower sheaves 21 and 22 arranged at the lower part. Of these, the two lower sheaves 21 and 22 arranged at the lower part are arranged on the front side (extension side) of the upper sheave 23 arranged at the upper part when viewed in the boom expansion / contraction direction. That is, the lower sheaves 21 and 22 are arranged in the jaw-shaped protruding portions of the left side plate 41 and the right side plate 42. Here, the number of lower sheaves is not limited to two, and may be three or more. Further, when not used with three or more hooks, the number of lower sheaves may be only one.

More specifically, the pin 43 is arranged substantially directly below the upper sheave 23, and the lower sheaves 21 and 22 are arranged on the front side (extended side when viewed in the boom expansion / contraction direction) of the pin 43. .. That is, the pin 43 on the rear side and the lower sheaves 21 and 22 on the front side are separated by a predetermined distance.

Similarly, two sheaves 31 and 32 are arranged on the hook (hook block) 17. Then, the wire rope 16 unwound from the winch 45 (see also FIG. 4) is hung between the two lower sheaves 21 and 22 and the two sheaves 31 and 32 on the hook side. The number of sheaves on the hook side is not limited to two, and may be one (sub-hook) or three or more.

Specifically, in the case of two hooks, the wire rope 16 is wound around the first lower sheave 21 and the first sheave 31 on the hook side in order, and is on the boom head 40 side. Terminate with. In this way, the load is supported (suspended) by the two wire ropes 16 laid between the boom head 40 and the hook 17.

Similarly, in the case of four hooks, the wire rope 16 has, in order, a first lower sheave 21, a first sheave 31 on the hook side, a second lower sheave 22, and a second hook side. It is wound around the sheave 32 of 2 and terminated on the boom head 40 side. In this way, the load is supported (hung) by the four wire ropes 16 laid between the boom head 40 and the hook 17.

(Action when swinging jib)
Next, the operation of the rough terrain crane 1 provided with the boom head 40 of the present embodiment when the jib is swung will be described with reference to FIG.

First, the method of jib overhang will be described. The swinging operation of the jib 50 of the lower holding / swinging method is carried out by utilizing the rope tension of the wire rope 16 as described below. That is, after first engaging the boom 14 and the jib 50 in a horizontal state, the boom 14 is raised while the jib 50 is held in the lower position, and the boom 14 is extended to the guide that attaches the jib 50 to the boom 14. Along with this, the suspended position shown in FIG. 4 is assumed.

Next, by further winding up the wire rope 16 from the state where the hook 17 is in contact with the tip end portion of the jib 50, the jib 50 is swung forward (to the front side rather than the vertical side) against the self-weight moment. That is, by pulling the wire rope 16 upward, a clockwise moment with the pin 43 as the center of rotation acts, and the jib 50 rotates clockwise.

At the time of this swinging out, the boom head 40 of this embodiment can efficiently swing out the jib 50. That is, since the lower sheaves 21 and 22 are arranged so as to be offset forward from the pin 43 at a predetermined distance, the arm length of the moment at the time of swinging is secured, and the jib 50 can be easily swung up. It is.

After that, the base end sides of the tension rods 60 and 60 are connected to the boom head 40 side. Then, by expanding and contracting the tilt cylinder (not shown), the tilt angle of the jib 50 is set, and the crane work can be performed.

(effect)
Next, the effects of the boom head 40 of this embodiment will be listed and described.

(1) As described above, the boom head 40 is rotatably supported between the left side plate 41 and the right side plate 42 arranged facing the tip of the boom 14 and the left side plate 41 and the right side plate 42. A boom head 40 comprising a plurality of sheaves 21-23, wherein the plurality of sheaves are one upper sheave 23 located above between the left side plate 41 and the right side plate 42, and the left side plate 41 and the right side plate. It is composed only of a plurality of lower sheaves 21 and 22 arranged in the lower part between 42. According to such a configuration, the boom head can be used for both the main hook and the sub hook while achieving weight reduction.

That is, in the case of the boom head 40 of the present embodiment, only one upper sheave 23 and two lower sheaves 21 and 22 can be used to hang one to four, but a minimum of three. The weight of the boom head 40 can be reduced by the configuration of the sheaves 21 to 23. Therefore, the lifting performance can be improved. Further, by using only one wire rope 16, further weight reduction can be achieved.

Further, by arranging the two lower sheaves 21 and 22 coaxially, the vertical width (length in the boom expansion / contraction direction) of the boom head 40 can be shortened. This makes it possible to secure the required approach angle.

(2) Further, since the plurality of lower sheaves 21 and 22 are arranged on the front side of the upper sheave 23, the length of the arm from the pin 43 can be lengthened when the jib 50 is swung up. , It is easy to swing up the jib 50. That is, since the lower sheaves 21 and 22 are arranged so as to be offset forward from the pin 43 at a predetermined distance, the arm length of the moment when the jib 50 is swung can be lengthened, and the jib 50 can be easily swung up. It has become. In addition, in the posture in which the boom 14 is raised, the lower sheaves 21 and 22 arranged on the front side are located above, so that the lift can be extended to the highest possible position.

(3) Further, since the pin 43 to which the base end portion of the jib 50 is engaged when the jib 50 is attached is installed on the rear side of the plurality of lower sheaves 21 and 22, the rigidity of the boom head 50 is increased. Can be secured. That is, conventionally, the rotation axis of the sheave is located near the position of the pin 43 of the present invention, thereby ensuring the rigidity. On the other hand, in the present invention, since there is no axis of rotation of the sheave at the conventional position, rigidity is ensured by penetrating the pin 43. Further, since the rotation axes of the pin 43 and the lower sheaves 21 and 22 are separated from each other, it becomes easier to pass the cord end.

Although the embodiments of the present invention have been described in detail with reference to the drawings, the specific configuration is not limited to this embodiment, and design changes to the extent that the gist of the present invention is not deviated are made in the present invention. included.

1: Rough terrain crane (mobile crane);
14: Boom;
40: Boom head;
41: Left side plate; 42: Right side plate; 43: Pin;
21: Lower sheave; 22: Lower sheave; 23: Upper sheave;
31-33: Sheave (on the hook side);
50: Jib; 60: Tension rod

Claims (2)

The left and right plates that are placed facing the tip of the boom,
A boom head comprising a plurality of sheaves rotatably supported between the left side plate and the right side plate.
The plurality of said sheaves is composed of only one upper sheave arranged at the upper part between the left side plate and the right side plate and a plurality of lower sheaves arranged at the lower part between the left side plate and the right side plate. Ori,
A pin to which the base end portion of the jib is engaged when attaching the jib is installed on the rear side of the plurality of lower sheaves so as to penetrate the both side plates, and when the jib is shaken, the pin is installed. A boom head in which a wire rope tension is applied between the tip of the jib and the upper sheave via the lower sheave . The boom head according to claim 1, wherein the plurality of lower sheaves are arranged on the front side of the upper sheave.

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