JP2824032B2 - Boom head attachment / detachment device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a boom head attaching / detaching apparatus for attaching / detaching a boom head to / from a tip of a boom such as a crane.

[0002]

2. Description of the Related Art Conventionally, for example, a box boom 2 is provided on an upper revolving structure 1 of an all terrain crane shown in FIG. A boom head 3 is attached to the tip of the box boom 2. The boom head 3 has a boom point idler sheave 5 around which the main hoisting rope 4 is wound and a boom point
Main sheave 6 is pivoted. This boom head 3
Various work attachments are attached to the. For example, the luffing jib is attached to the boom head 3 as a work attachment by a jib attaching / detaching device disclosed in Japanese Utility Model Laid-Open No. 5-46879. In this publication, a jib foot of a luffing jib is lifted by a wire rope suspended from a tip of a boom head, and the jib foot is placed on a gantry. Then, a jib foot of a luffing jib is attached to the tip of the boom head.

[0003]

In the crane having the above-mentioned conventional structure, the boom head 3 is attached to the tip of the boom 2 by using an auxiliary crane, and there is conventionally a device for attaching and detaching the boom head itself. Did not. For this reason, conventionally, the workability of assembling the crane was not good, and a wide work space was required at the time of assembling.

In the case of a large crane, the boom head 3 is also large. Therefore, conventionally, there has been a problem that the boom head 3 obstructs the front view of the carrier cab 7 during traveling on the premises.

[0005] In addition, attachment and detachment of the work attachment to and from the boom head has conventionally been performed by suspending and lifting the center of gravity of the attachment. However, the center of gravity of the work attachment differs depending on the type of the attachment. For this reason, attachment / detachment of the attachment to / from the boom head is conventionally performed as exemplified in the above-mentioned publication.
It is performed by a self-removing device unique to each attachment. Therefore, it is necessary to prepare a detachable device suitable for each attachment depending on the type of attachment attached to the boom head, and the work efficiency is not good.

[0006]

SUMMARY OF THE INVENTION The present invention has been made in order to solve the above-mentioned problems, and comprises a locking portion provided at a boom head portion facing a boom tip portion, and a boom and a boom head. A first sheave attached to a boom tip where the rope is hung and the boom head is suspended, and a second sheave that changes the direction in which the rope is hung on the first sheave. A sheave, a first cylinder having one end fixed to the boom,
A third sheave pivotally supported by the other end of the first cylinder and having a rope diverted by the second sheave wrapped around the second sheave, and a second end moving below the first sheave. A boom head attachment / detachment device is provided including a cylinder and an engaging portion provided at the end of the second cylinder and engaging with a locking portion of the boom head.

[0007]

By extending the first cylinder, the distance between the second and third sheaves is increased, and the length of the rope connected between the boom and the boom head is increased between these sheaves. Therefore, the length of the rope stretched between the first sheave and the boom head is relatively short, and the boom head is lifted via the first sheave. At this time, the second cylinder is extended, and the engaging portion provided on the second cylinder is projected from the boom tip. By further extending the first cylinder, the boom head is further lifted and approaches the boom tip, and the locking portion of the boom head comes into contact with the engaging portion provided on the second cylinder. By contracting the second cylinder in this state, the engaging portion provided on the second cylinder is engaged with the locking portion of the boom head, and the boom head is drawn toward the boom tip. By further extending the first cylinder in this state, the boom head rotates about this engaging portion, and the boom head is arranged to face the boom tip. At this time, by expanding and contracting the second cylinder,
The displacement of the center of gravity when lifting the boom head is absorbed. Further, the boom head is mounted on the boom tip by adjusting the length of each of the first and second cylinders.

Further, by extending the second cylinder during traveling on the premises, the boom head is pushed up through the engaging portion.

Also, due to the expansion and contraction of the first and second cylinders, the boom head rotates around the engagement portion with the second cylinder and is detached from the boom tip regardless of the position of the center of gravity. . Therefore, the attachment attached to the boom head is also attached to and detached from the boom tip together with the boom head regardless of the position of the center of gravity.

[0010]

Next, an embodiment in which the boom head attaching / detaching apparatus according to the present invention is applied to an all terrain crane will be described.

The schematic structure of the boom head attaching / detaching apparatus according to the present embodiment will be described as follows with reference to the side view of FIG.

A pair of wire ropes 13 is connected between the boom base 11 and the boom head 12 at the box boom tip of the all terrain crane. That is, one end 13 a of each wire rope 13 is connected to both sides of the boom head 12 by the pin 14, and the other end 13 b of each wire rope 13 is connected to the upper end of the boom base 11 by the pin 15.

A bracket 16 is provided at the tip of the boom base 11. The boom head 12 is housed between the brackets 16. A first sheave 18 is attached to each bracket 16 around a cylindrical pin 17. The wire rope 13 is hung on the first sheave 18, and the boom head 12 is suspended. Also, the pin 15 to which the wire rope end 13b is connected is connected.
A second sheave 19 is attached to the lower boom base 11 by a pin 20. This second sheave 1
9 is a wire rope 13 hung on the first sheave 18.
Is changing the direction in which it is wound. Also, the second sheave 19
The tube end of the first hydraulic cylinder 21 is fixed by a pin 20 pivotally supporting the first hydraulic cylinder 21. A third sheave 22 is pivotally supported at the other end of the first hydraulic cylinder 21, and a wire rope 13 whose direction is changed by a second sheave 19 is looped around the third sheave 22. The third sheave 22 moves in the left and right direction in the figure due to the expansion and contraction of the first hydraulic cylinder 21. These first, second and third sheaves 18, 19, 22
The first and second hydraulic cylinders 21 are provided in pairs on the left and right sides of the center of the box boom, respectively.
The sheaves 19 and 22 and the first hydraulic cylinder 21 are provided in a box boom.

The boom base 11 below the center of the box boom
Is provided with one second hydraulic cylinder 23,
The rod-side tube end of the second hydraulic cylinder 23 is attached to the boom base 11 by a pin 24.
A hook member 25 is provided at the rod end of the second hydraulic cylinder 23, and a concave engaging portion 25 a is formed at the tip of the hook member 25. The extension of the rod of the second hydraulic cylinder 23 causes the hook member 25 at the rod end to move below the first sheave 18.

On the other hand, a pair of brackets 26 are provided on one side surface of the boom head 12.
A pin 27 extends between the six. The pin 27 forms a locking portion, and is engaged with the engaging portion 25 a of the hook member 25 attached to the second hydraulic cylinder 23. The side surface of the boom head 12 provided with the pin 27 is a side surface facing the tip of the boom base 11 when the boom head is mounted. A positioning stopper 28 is provided on this side surface, and the mounting position of the boom head 12 is guided using the positioning stopper 28 as described later. Further, a pin insertion hole 29 is provided on a side surface of the boom head 12, and a pin is inserted into the pin insertion hole 29 and the cylindrical pin 17 pivotally supporting the first sheave 18, as described later. The head 12 is attached to the boom base 11.

The sheave 30 is a boom point main sheave around which the main hoisting rope is wound. The boom point idler sheave is juxtaposed to the first sheave 18 on the side of the boom base 11, but is not shown. A luffing jib, which is a work attachment, is attached to the jib receiving portion 33 as described later.

The operation of mounting the boom head using the boom head attachment / detachment device according to the present embodiment in such a structure will be described below with reference to the side views of FIGS.

First, the wire rope 13 is pulled out with the first hydraulic cylinder 21 contracted, and one end 13a of the wire rope 13 is attached to the boom head 12 on the ground (see FIG. 1). Next, oil is supplied to the first hydraulic cylinder 21 and its rod is extended (see FIG. 2). First
When the hydraulic cylinder 21 is extended, the distance between the second and third sheaves 19 and 22 is increased, and the wire rope 13 connected between the boom base 11 and the boom head 12 has a length extending between the sheaves 19 and 22. Becomes longer. Therefore, the first sheave 18 and the boom head 1
The length of the rope stretched between the two becomes relatively short, and the boom head 12 is lifted via the first sheave 18. At this time, the oil is also supplied to the second hydraulic cylinder 23, and the rod of the second hydraulic cylinder 23 is also extended, so that the engaging portion 25a of the hook member 25 at the rod end is projected from the tip of the boom base 11.

When the rod of the first hydraulic cylinder 21 is further extended, the boom head 12 is further lifted and approaches the tip of the boom base 11, and the pin 27 of the boom head 12 comes into contact with the hook member 25 (FIG. 2). 3
reference). In this state, when the rod of the second hydraulic cylinder 23 is contracted, the engaging portion 25a provided at the rod end of the second hydraulic cylinder 23 moves rightward in the drawing, and the pin 27 of the boom head 12 Engage (see FIG. 4). Therefore, by further contracting the rod of the second hydraulic cylinder 12, the boom head 12 is drawn to the tip of the boom base 11. In this state, the first hydraulic cylinder 2
By further extending 1, the boom head 12 is pulled upward with the pin 14 as a hanging point, and rotates around the pin 27. At this time, by moving the hook member 25 right and left by expanding and contracting the second hydraulic cylinder 23, the displacement of the center of gravity when lifting the boom head 12 is absorbed,
Further, the center of rotation of the boom head 12 is adjusted. As a result of this rotation operation, one side surface of the boom head 12 on which the pin 27 is provided is arranged to face the tip of the boom base 11.

Further, the first and second hydraulic cylinders 21 and 23 are alternately operated to adjust the lengths of the respective cylinders, whereby the boom head 12 is retracted between the brackets 16 of the boom base 11. At this time, the positioning stopper 28 of the boom head 12 abuts on the lower part of the tip of the boom base 11, and the mounting position of the boom head 12 to the boom base 11 is guided. By this position guide, the pin insertion hole 29 of the boom head 12 and the shaft hole of the cylindrical pin 17 pivotally supporting the first sheave 18 are aligned, and the pin 31 is inserted into each of these holes (see FIG. 5). This pin 31
The upper end of the boom head 12 is
6 and the attachment of the boom head 12 to the boom base 11 is completed.

On the other hand, the operation of removing the boom head using the boom head attaching / detaching apparatus according to the present embodiment is performed in the reverse order of the above-described mounting operation.

According to the boom head attachment / detachment device according to the present embodiment, the boom head 12 is detachably attached to the tip of the boom by itself without using an auxiliary crane as in the conventional art. For this reason, labor can be saved, and the assembling workability of the all terrain crane is improved. Moreover, there is no need for a large work space when assembling the crane.

In the case of a large crane, the boom head is large, and the boom head obstructs the field of view in front of the carrier cab during traveling on the premises. Will be resolved. In other words, as shown in FIG. 6, during traveling on the premises, by extending the second hydraulic cylinder 23, the boom head 12 is pushed up through the engaging portion with the second hydraulic cylinder 23, and tilts up. . In this figure, the same or corresponding parts as those in FIGS. 1 to 5 are denoted by the same reference numerals, and description thereof will be omitted. Also, the boom head 1 shown in FIG.
2 has a different shape from that shown in FIGS. 1 to 5, and a single top 34 is newly provided in the boom head 12, but the essential structure of the boom head attaching / detaching device is as shown in FIG.
5 is not different from that shown in FIG.

As described above, the boom head 1 is used during traveling on the premises.
2 is tilted up so that the carrier cab 3
The boom head 12 disappears from the front view 5. That is, even in the case of a large all terrain crane,
It is possible to easily secure a forward view, and it is possible to improve safety.

The first and second cylinders 21 and
Due to the expansion and contraction of 3, the boom head 12 rotates about the pin 27 which is an engagement portion with the second hydraulic cylinder 23 regardless of the position of the center of gravity, and is attached to and detached from the tip of the boom base 11. For this reason, the work attachment attached to the boom head 12 also does not depend on the position of the center of gravity.
It is attached to and detached from the tip of the boom base 11 together with the boom head 12. For example, when the work attachment is a luffing jib, the attachment is attached as shown in FIG.

When the crane arrives at the work site, the boom head 12 that has been tilted up during traveling on the premises is set to the work position shown in FIG. 1A, and the single top 34 is folded. Then, after the floor plate 37 is installed under the outrigger 36, a counterweight 38 is attached to the rear end of the upper swing body. A luffing jib 39 as a work attachment is assembled on the ground in front of the crane. At this time, the relay jib 39a and 39b
When assembling, only the upper pin 40 is inserted and the lower pin is not inserted. Next, in a state where the boom is contracted most and is horizontally tilted, the first sheave 18 described above is used.
The boom head 12 is removed from the tip of the boom base 11 and lowered by the first hydraulic cylinder 21 being contracted by removing the pin 31 inserted into the boom head 11. next,
The luffing jib 3 is attached to the jib receiving portion 33 of the boom head 12.
Nine jib feet 39c are connected by foot pins. Thereafter, when the first hydraulic cylinder 21 is extended, the boom head 12 is lifted together with the roughing jib bottom as shown in FIG. Subsequently, by operating the first and second hydraulic cylinders 21 and 23 as described above, the boom head 12 with the luffing jib bottom attached thereto is moved to the tip of the boom base 11 as shown in FIG. Attached to the unit. At this time, the relay jib 39a rotates upward about the upper pin 40 as shown.

Next, the luffing jib undulating wire rope and the main winding wire rope are wired. Thereafter, the luffing jib 39 is lifted and the connecting pin 4 on the lower side of the jib is inserted between the joint jib 39a and 39b.
1 is inserted. As a result, the luffing jib 39 is set on the boom head 12 as shown in FIG.

As described above, according to the present embodiment, the luffing jib 39, which is a work attachment, is attached to the boom base 12 and the boom base 11 regardless of the position of the center of gravity.
Detachable to the tip of That is, various attachments can be attached to the boom head 12 on the ground, and then the attachments are detached to the boom base 11 together with the boom head 12. Therefore, conventionally,
A unique self-removing device that had to be prepared each time according to the type of attachment is not required, and the attachment and detachment of the work attachment to and from the boom head 12 can be performed in a general-purpose manner. As a result, the assemblability of the crane can be improved, and the working efficiency can be improved.

In the above description, the work attachment is a luffing jib, but other work attachments that require attachment / detachment at the tip of the main boom, such as a tilt jib and an additional jib, can also be detached by themselves.

In the above embodiment, the case where the boom head attaching / detaching apparatus according to the present invention is applied to an all terrain crane has been described. However, the present invention can be applied to other construction machines in the same manner. The same effect as the example is achieved.

[0031]

As described above, according to the present invention, the boom head is detachably attached to the end of the boom by itself without using an auxiliary crane. For this reason, labor can be saved, and the workability of assembling the construction machine is improved. Moreover, there is no need for a large work space at the time of assembly.

When the second cylinder is extended during traveling on the premises, the boom head is pushed up through the engaging portion. Therefore, a front view of the carrier cab can be secured during traveling on the premises, and safety is improved.

Also, due to the expansion and contraction of the first and second cylinders, the boom head rotates about the engagement portion with the second cylinder and is detached from the boom tip regardless of the position of the center of gravity. . Therefore, the attachment attached to the boom head is also attached to and detached from the boom tip together with the boom head regardless of the position of the center of gravity. Therefore, after attaching the attachment to the boom head on the ground, the attachment together with the boom head can be detached and attached to the boom tip by itself. Therefore, attachment and detachment of the attachment to and from the boom head can be performed in a general-purpose manner, and assemblability can be improved.

[Brief description of the drawings]

FIG. 1 is a side view showing a first step of a boom head mounting operation using a boom head attaching / detaching device according to an embodiment of the present invention.

FIG. 2 is a side view showing a second step of the boom head mounting operation using the boom head attaching / detaching device according to the embodiment.

FIG. 3 is a side view showing a third step of the boom head mounting operation using the boom head attaching / detaching device according to the embodiment.

FIG. 4 is a side view showing a fourth step of the boom head mounting operation using the boom head attaching / detaching device according to the present embodiment.

FIG. 5 is a side view showing a state in which the boom head is mounted on the boom tip using the boom head attaching / detaching device according to the present embodiment.

FIG. 6 is a side view of the all-terrain crane equipped with the boom head attaching / detaching device according to the present embodiment when traveling inside a premises.

FIG. 7 is a side view showing a self-attachment operation of the work attachment using the boom head attaching / detaching device according to the embodiment.

FIG. 8 is a side view showing a state in which the work attachment is mounted by itself using the boom head attaching / detaching device according to the present embodiment.

FIG. 9 is a side view of a conventional all terrain crane.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 ... Boom base 12 ... Boom head 13 ... Wire rope 14, 15, 20, 24, 31 ... Pin 16, 26 ... Bracket 17 ... Cylindrical pin 18 ... First sheave 19 ... Second sheave 21 ... First Hydraulic cylinder 22 ... Third sheave 23 ... Second hydraulic cylinder 25 ... Hook member 25 a ... Engagement part 27 ... Pin (locking part) 28 ... Positioning stopper 29 ... Pin insertion hole 30 ... Boom point main sheave

Claims (1)

(57) [Claims] 1. A boom provided on a boom head portion facing a boom tip, a rope connected between the boom and the boom head, and the boom on which the rope is hung and the boom head is suspended. A first sheave attached to the tip of the first sheave, a second sheave attached to the boom that changes the direction in which the rope is hung on the first sheave, and one end fixed to the boom. A first cylinder, a third sheave pivotally supported by the other end of the first cylinder and around which the rope whose direction is changed by the second sheave is looped, and a third sheave below the first sheave; A second cylinder attached to the boom having an end moving, and an engaging portion engaging with the engaging portion of a boom head provided at the end of the second cylinder. Was Boom head attachment / detachment device.