JPH0930779A - Counterweight attaching and detaching device of mobile crane - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make a sufficient weight securable by way of enlarging a size of height in a counterweight, and also the same cylinder and this counterweight so as to be connectible and separable in a simple manner. SOLUTION: A weight attaching and detaching cylinder 16 making a counterweight 13 go up or down is overhung together with a swivel slide lifter 9 and attached to this lifter 9 for uplifting and supporting a swivel slide 5 in a state of being shiftable in the storage direction, while a lower end of this weight detachable cylinder 16 and the counterweight 13 both are connected by movements of the lifter 9 in the storage direction, through which they are so constituted by the movements of the lifter 9 in the overhanging direction.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a counterweight attaching / detaching device for attaching / detaching a counterweight by itself in a mobile crane such as a truck crane.

[0002]

2. Description of the Related Art Conventionally, in a large-sized mobile crane (truck crane, crawler crane), due to the weight limitation during transportation, it is disassembled into three parts, a lower traveling body, a swivel base and a boom, and a counterweight. Shipped separately.

In this case, as a counterweight attaching / detaching device for removing the counterweight from the swivel base by itself without using a separate crane and reattaching it after transportation, as disclosed in Japanese Utility Model Publication No. 61-43836, It is known to utilize both front and rear swivel lifters provided on both front and rear sides of the swivel.

This swivel lifter is constructed so that it can be extended and stored in the swivel width direction, and that the jack cylinder provided at the tip of the swivel can be lifted and supported in the extended state by grounding the jack cylinder. There is.

In the known device, the lower end of the jack cylinder of the swivel lifter is detachably connected to a counter weight, and the weight is hung below the cylinder.
At the time of disassembling the crane, the cylinder is extended to place the counterweight on the ground and is removed from the lower end of the cylinder, that is, the jack cylinder is also used as a lifting means for the counterweight.

[0006]

However, the known device has the following drawbacks.

The jack cylinder originally has a long cylinder length because it requires a stroke for grounding from the swivel side and for lifting the swivel base.

Since the upper end position of the cylinder is regulated by the height limit during transportation with the trailer loaded,
Lower cylinder bottom position.

The counterweight, which is suspended from the jack cylinder, must be positioned above the lower traveling body so as not to interfere with the lower traveling body during turning.

Due to these three points, the height dimension of the counterweight is limited to a small value, so that the weight weight becomes light and the original counter function cannot be sufficiently fulfilled.

In addition to the jack cylinder, it may be possible to vertically install a cylinder for attaching and detaching the counterweight on the swivel base.

With this configuration, the cylinder need only have a stroke for moving between the mounting position and the installation position when the counterweight is removed, so that the cylinder length is longer than that of the jack cylinder of the swivel lifter. Can be shortened. Therefore, it is possible to increase the height of the counterweight and secure a sufficient weight weight.

However, in this case, in order to detachably connect and separate the weight attaching / detaching cylinder, which performs only vertical expansion / contraction movements, and the counterweight, for example, a troublesome work such as bolting the lower end of the cylinder to the weight upper surface is removed. Therefore, the work of attaching / detaching the counterweight becomes inefficient.

Therefore, according to the present invention, by using a dedicated weight attaching / detaching cylinder, the height dimension of the counter weight can be increased to secure a sufficient weight weight, and the cylinder and the counter weight can be easily connected / separated. A counterweight attaching / detaching device for a mobile crane capable of

[0015]

According to a first aspect of the present invention, a swivel having a boom is mounted on a lower traveling body so as to swivel about a vertical axis, and a counter weight is detachably attached to a rear end of the swivel. In a mobile crane provided with a swivel lifter capable of overhanging / storing in the swivel width direction and lifting and supporting the swivel in the overhanging state, the swivel lifter includes:
A weight detachable cylinder that can be expanded and contracted in the vertical direction is attached to the lifter so that it can be extended and moved in the storage direction.The lower end of this weight detachable cylinder and the counterweight have their engaging parts extended by the same cylinder. In this state, the swivel lifter is engaged in the retracted direction when it is moved, and is disengaged when the lifter is moved in the extended direction.

According to a second aspect of the present invention, in the configuration of the first aspect, the engaging portions of the counterweight and the weight attaching / detaching cylinder are provided on a straight line in the swivel width direction passing through the center of gravity of the counterweight.

According to a third aspect of the present invention, in the structure according to the first or second aspect, the engaging portion of the weight attaching / detaching cylinder is provided with a convex portion projecting to the cylinder outer peripheral side at the lower end portion of the cylinder, and the counterweight is engaged. As the joint portion, concave grooves are provided on the right and left sides of the upper surface of the weight, with which the convex portion engages from the side surface of the weight.

According to a fourth aspect of the present invention, in the structure according to any one of the first to third aspects, the weight mounting surface on which the counterweight is mounted in a detached state on the turning trajectory of the counterweight on the upper surface of the lower traveling body. Is provided, and weight positioning means for engaging the weight mounting state and positioning the counterweight on the weight mounting surface is provided on the weight mounting surface and the lower surface of the counter weight.

According to the above construction, with the weight attaching / detaching cylinder positioned right above the counterweight,
(I) The swivel lifter is extended to position the weight attaching / detaching cylinder on the outer side of the counter weight, and (ii) the weight attaching / detaching cylinder is extended to engage the engaging portion of the cylinder and the counterweight (the convex portion in claim 3). (Iii) Move the lifter in the retracted direction to engage the engaging parts, and (iv) reduce the weight attaching / detaching cylinder to lift the counterweight. The counterweight can be attached to the swivel base and the weight can be removed from the swivel base by performing the procedure and operation in the reverse order.

That is, by using a dedicated weight attaching / detaching cylinder different from the jack cylinder of the swivel lifter, it is possible to increase the height of the counterweight and secure a sufficient weight weight.

Moreover, the cylinder and the counterweight can be easily connected / separated by utilizing the lifting and retracting movements of the lifter.

In this case, according to the structure of claim 2, since the counterweight is suspended at the same front-back direction position as its center of gravity, there is no risk of the weight leaning in the front-back direction in this suspended state, and it is safe and The work of attaching and detaching the same weight to and from the swivel base becomes easier.

Further, according to the structure of claim 4, since the counterweight is placed at a specific position on the turning locus by the positioning means and its shift movement is prevented,
When mounting the weight, the weight attaching / detaching cylinder and the counter weight can be easily aligned by simply turning the turning base.

[0024]

BEST MODE FOR CARRYING OUT THE INVENTION In the following embodiments, a truck crane is applied as an example.

In FIG. 1, reference numeral 1 designates a lower traveling body which is driven by wheels 2. A pair of left and right outriggers 3 are provided on the front and rear sides of the lower traveling body 1, respectively. The lower traveling body 1 is lifted and supported on the ground by 3. Reference numeral 4 denotes a cabin for traveling operation provided in the front part of the lower traveling structure 1.

A swivel base 5 is mounted on the lower traveling body 1 so as to be freely swiveled around a vertical axis.

This swivel 5 is provided with a cabin 6 for crane work, a boom 7 that can be raised and lowered, a front swivel lifter 8 at the front end, and a rear swivel lifter 9 at the rear end. ing.

The front swivel lifter 8 is detachably attached to the swivel 5 and is removed during crane work. The front swivel lifter 8 may be detachably attached to the lower surface side of the boom 7.

Since the front and rear swivel lifters 8 and 9 have exactly the same structure, the rear swivel lifter 9 will be representatively shown below.
Only the configuration of FIG.

This rear swivel lifter 9 is shown in FIGS.
Etc., the left and right side beams 11, 11 are slidably fitted in a rectangular box-shaped fixed box 10 horizontally fixed on the swivel base 5, and the jack cylinders 12, 12 are attached to the tips of the both side beams 11, 11. Made up of.

The beams 11 on both sides are fixed to the fixed box 1
As a result of the expansion and contraction movement of a cylinder (not shown) provided between the jack cylinders 12 and 0, the jack cylinders 12 and 12 extend to the outside of the swivel base width as shown in FIG. 6, and the cylinders 12 and 12 as shown in FIG. Moves to and from the retracted position located within the swivel width, and the jack cylinder 12,
12 extends and contacts the ground to lift and support the swivel base 5.

By this operation being performed simultaneously by the front and rear swivel lifters 8 and 9 on both front and rear sides,
When the crane is disassembled and assembled, the swivel base 5 is independently supported, and in this state, the swivel base 5 is separated from the undercarriage 1.
Be combined.

A counterweight 13 is detachably attached to the rear end of the swivel base 5 (further rearward of the rear swivel lifter 9).

The counter weight 13 is attached by a pin (not shown) below the weight mounting base 14 which also serves as a fixed type counter weight when the crane is assembled, and is removed from the mounting base 14 when the crane is disassembled.

An apparatus for attaching and detaching the counterweight 13 by itself without using another crane will be described below.

Arms 15 and 15 are horizontally attached rearward to the jack cylinders 12 and 12 on both sides of the rear swivel lifter 9 and the weight attaching / detaching cylinders 16 and 1 shorter than the jack cylinders 12 and 12 are attached to the tips of the arms 15 and 15.
6 are attached.

The weight attaching / detaching cylinder 16 is vertically attached with its center located on the widthwise straight line L passing through the center of gravity O of the counterweight 13, and protrudes like a collar at the lower end (rod end) to the outer peripheral side. Convex part 1 as engaging part
7 are provided.

On the other hand, the counterweight 13 is provided with engaging portions for engaging the convex portions 17 of the weight attaching / detaching cylinder 16 from the side surface of the weight at positions on the widthwise straight line L passing through the center of gravity O of the weight on the left and right sides of the upper surface. The concave groove 18 is provided.

The concave groove 18 is formed in a convex shape in cross section in which the upper portion (side opening to the upper surface of the weight) is narrower than the lower portion, and the convex portion 17 engages with the concave groove 18 to attach and detach the weight. The cylinder 16 is connected to the counterweight 13 so that the counterweight 13 can be lifted.

As will be described later, the counterweight 13 is once lowered onto the front upper surface of the lower traveling body 1 at the time of removal, and then loaded on the transportation vehicle using the boom 7.

Therefore, a weight mounting surface 1a is provided at a position on the turning trajectory of the counterweight 13 on the front upper surface of the lower traveling body 1, and a projection 19 (FIG. 1, FIG. 1, as a positioning means) is provided on the weight mounting surface 1a. 5) is provided.

On the other hand, a concave hole 20 is provided in the lower surface of the counterweight 13, and the projection 19 is fitted into the concave hole 20 to position the counterweight 13 on the weight mounting surface 1a, which causes an unexpected displacement movement. To be prevented.

Next, the operation of attaching and detaching the counterweight 13 by this device will be described.

The rear swivel lifter 9 is in the storage state shown in FIG. 3 except when the crane is disassembled and assembled. At this time,
The weight attaching / detaching cylinder 16 is in a contracted state, and the convex portion 17
Is engaged with the groove 18.

When the weight is attached or detached, the outriggers 3 are extended as shown to lift and support the machine body.

When the weight is removed As shown in FIG. 4, the revolving base 5 is in a state in which the boom 7 is facing rearward, that is, the counterweight 13 is located right above the weight mounting surface 1a, which is the reverse of the normal traveling. Turn to the state.

Next, the weight attaching pin is removed to release the fixing of the counter weight 13, and then the weight attaching / detaching cylinder 16 is extended to lower the counter weight 13 onto the weight mounting surface 1a.

In this case, since the counterweight 13 is hung at the same position as the center of gravity O in the front-rear direction, there is no possibility that the weight 13 is tilted in the front-rear direction.

As shown in FIG. 6, the rear swivel lifter 9
Project the beam 11 of. As a result, the weight attaching / detaching cylinder 16 moves outward together with the beam 11, and the convex portion 17
Is disengaged from the groove 18 of the counterweight 13 and separated.

After the weight attaching / detaching cylinder 16 is contracted, the beam 11 of the lifter 9 is stored.

Thereafter, the swivel base 5 is returned to the frontward state shown in FIG. 1, the boom 7 is raised, and the counterweight 13 removed.
Is lifted from the weight mounting surface 1a and loaded on the transportation vehicle, whereby the work of removing the counterweight 13 is completed.

At the time of attaching the weight This is due to the reverse procedure and operation to the case of removing the weight.

That is, the counterweight 13 is lifted from the transportation vehicle and lowered to the weight mounting surface 1a.

At this time, the protrusion 19 of the weight mounting surface 1a
By engaging with the concave hole 20 of the counterweight 13, the weight 13 can be accurately placed at a specific position on the turning locus, and its shift movement can be prevented. Therefore, when the weight is attached, the weight attaching / detaching cylinder 16 can be accurately and easily positioned directly above the counterweight 13 simply by turning the turntable 5.

The swivel base 5 is swiveled to the rearward state.

The beam 11 of the rear swivel lifter 9 is once stretched, and the weight attaching / detaching cylinder 16 is extended.

The beam 11 of the lifter 9 is retracted and moved to engage the convex portion 17 with the concave groove 18.

By reducing the weight attaching / detaching cylinder 16, the weight 13 is lifted and fixed to the weight mount 14.

According to this apparatus, the weight attaching / detaching cylinder 16 attaches the counter weight 13 to the weight mounting surface 11.
The cylinder length is much shorter than that of the jack cylinder 12 of the swivel lifter 9 because there is only a stroke required to move between the upper mounting position and the installation position by the weight mounting base 14.

Therefore, the height of the counterweight 13 can be increased to ensure a sufficient weight weight.

Moreover, the beam 11 of the rear swivel lifter 9
Cylinder for attaching / detaching weight by utilizing the overhang and retracting movement of the cylinder 1
6 and the counterweight 13 can be easily connected and separated.

By the way, although the weight attaching / detaching cylinder 16 is attached to the jack cylinder 12 of the rear swivel lifter 9 in the above embodiment, it may be attached to the beam 11.

In the above embodiment, the counterweight 13 is placed on the upper surface of the lower traveling body 1, but
A configuration may be adopted in which the weight 13 is lowered on a table placed on the ground while the swivel table 5 is in the horizontal direction.

[0064]

As described above, according to the present invention, a weight attaching / detaching cylinder for raising / lowering a counter weight can be integrally extended to the swivel lifter provided at the rear end of the swivel base and moved in the storing direction. Installed in a state, the lower end of this weight attachment / detachment cylinder and the counterweight are connected by moving the lifter in the storage direction, and separated by moving the lifter in the extension direction. As compared with the case where the counter weight is moved up and down by the above, the height dimension of the counter weight can be increased to secure a sufficient weight weight.

Moreover, the cylinder and the counter weight can be easily connected / separated by utilizing the extension / retraction movement of the swivel lifter.

In this case, according to the invention of claim 2, since the counterweight is suspended at the same front-back direction position as the center of gravity of the counterweight, there is no risk of the weight tilting in the front-back direction in this suspended state, and it is safe and The work of attaching and detaching the same weight to and from the swivel base becomes easier.

Further, according to the invention of claim 4, since the counterweight is placed at a specific position on the turning locus by the positioning means and the shift movement thereof is prevented,
When attaching the weight, the weight attaching / detaching cylinder and the counter weight can be accurately and easily aligned simply by turning the turning base.

[Brief description of drawings]

FIG. 1 is an overall schematic side view of a truck crane equipped with a counterweight attaching / detaching device according to an embodiment of the present invention.

FIG. 2 is a partially enlarged view of FIG.

3 is a sectional view taken along line III-III in FIG.

FIG. 4 is a view corresponding to FIG. 1 showing a state where the counter weight is removed.

5 is a partially enlarged view of FIG.

6 is a sectional view taken along line VI-VI of FIG.

[Explanation of symbols]

 1 Undercarriage 1a Weight mounting surface 5 Revolving base 9 Revolving base lifter provided at the rear end of the revolving base 10 Fixed box that constitutes the revolving base lifter 11 Beam 12 Jack cylinder 16 Weight attaching / detaching cylinder 17 Engagement part of the weight attaching / detaching cylinder 18 as a counterweight, a concave groove as an engaging portion of a counterweight, 19 as a positioning means, 20 as a concave hole

Claims (4)

[Claims] 1. A swivel equipped with a boom is mounted on a lower traveling body so as to be freely swiveled around a vertical axis, and a counterweight that is detachable at the rear end of the swivel and can be extended and stored in the swivel width direction. In a mobile crane equipped with a swivel lifter that lifts and supports the swivel in the overhanging state, a weight detachable cylinder that is vertically expandable and retractable moves integrally with the swivel lifter in the overhanging / storing direction. Mounted in a loose state, the lower end of the weight attaching / detaching cylinder and the counterweight have respective engaging portions.
A counterweight attachment / detachment of a mobile crane, characterized in that the counterweight is engaged and disengaged when the swivel lifter moves in the retracted direction when the cylinder is extended, and disengaged when the lifter moves in the extension direction. apparatus. 2. The counterweight of a mobile crane according to claim 1, wherein the counterweight and the engaging portion of the weight attaching / detaching cylinder are provided on a straight line passing through the center of gravity of the counterweight in the swivel width direction. Detachable device. 3. An engaging portion of a weight attaching / detaching cylinder,
A convex portion projecting to the cylinder outer peripheral side is provided at the lower end of the cylinder, and a concave groove for engaging the convex portion from the side surface of the weight is provided on both left and right upper surfaces of the weight as an engaging portion of the counter weight. The counterweight attaching / detaching device for a mobile crane according to claim 1 or 2, characterized in that. 4. A weight mounting surface on which the counterweight is mounted in a detached state is provided on the turning trajectory of the counterweight on the upper surface of the lower traveling body, and the weight mounting surface and the lower surface of the counterweight are provided with weights. The counterweight attaching / detaching device for a mobile crane according to any one of claims 1 to 3, further comprising weight positioning means that engages in a mounted state to position the counterweight on the weight mounting surface.