JPS6139751Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a counterweight attachment/detachment device attached to the rear end of a base machine in a crane.

Conventionally, when a counterweight is attached or detached when a crane is disassembled and transported, a separate crane is generally used, but this is not only uneconomical but also has poor work efficiency. On the other hand, as another method, a method has been proposed in which a gantry for raising and lowering a boom (or leader) installed on a base machine is used as a counterweight lifting mast. This method utilizes the up-and-down motion of the gantry to move the weight back and forth, but there is a problem in that the amount of back and forth movement of the weight is insufficient if the gantry is used alone. Conventionally, when using this method, auxiliary devices such as hydraulic cylinders and equalizers are used to compensate for the lack of longitudinal movement, but the disadvantages in terms of economy and work efficiency have not yet been resolved. The reality is that it is not.

In view of the above points, the present invention is a counterweight for a crane that can easily attach and detach the counterweight by oneself using a gantry, without using another crane or any auxiliary equipment such as a hydraulic cylinder. The purpose is to provide a weight attaching/detaching device.

The features of the present invention are that a weight mounting table is provided at the rear end of the base machine, a counterweight is removably installed on the weight mounting table, and the front part of the counterweight in the base machine is undulating. A flexible gantry is installed,
This gantry consists of a front strut, a telescopic rear strut that is made up of telescopically connecting members in three stages: base, middle, and tip, and the tips of both the front and rear struts are connected to each other. In a crane configured with a gantry sheave provided at the gantry peak part and a gantry hoisting cylinder provided between the base end member and the intermediate member in the rear column, the above-mentioned gantry and a base machine mounted on the The counterweight attachment/detachment device uses a winch to attach/detach the counterweight, and the counterweight attachment/detachment device includes a sheave bracket protruding rearward from the gantry peak portion, and a wire pulled out from the winch is passed through the sheave bracket. While installing a sheave for attaching and detaching the counterweight,
A pin hole is provided in both the intermediate and tip members of the rear column of the gantry to fix the tip member to the intermediate member at an intermediate position between fully extended and fully retracted, and the sheave for attaching and removing the counterweight When the gantry is fixed at an intermediate position and the gantry is upright, the counterweight can be raised and lowered above the weight mounting table, and when the gantry is folded down, the counterweight can be raised and lowered behind the weight mounting table. It is based on the following points.

Embodiments of the present invention will be described below with reference to the drawings.

Reference numeral 1 denotes a base machine, which consists of a lower traveling body 2 and an upper revolving body 3, with a boom when used as a crane for lifting loads, and a boom when used as a pile driver. A reader (not shown) is attached to each front end, either via or directly. In this embodiment, a case where the pile driver is used is taken as an example, and 4 is a leader support supporting the lower part of the leader, and 5 is a wire guide sheave attached to this leader support 4. Reference numeral 6 denotes a winch for main hoisting (or for auxiliary hoisting) mounted on the revolving body 3. During pile driving work, the wire 7 pulled out from this winch 6 is guided to the upper end sheave of the leader via the guide sheave 5. It will be destroyed. 8 is a counterweight detachably attached to the rear end of the upper revolving body 3 via a weight mounting table 9;
is the gantry.

This gantry 10 is configured to be movable in the front-rear direction by a front column 11 and a rear column 12 which is extendable and retractable. The front strut 11 has a base end rotatably attached to the front part of the upper revolving body 3 via a pin 13. The rear strut 12 is configured to be expandable and retractable by telescopically fitting and connecting three stages of members 14, 15, and 16 at the base, middle, and tip. It is pivotably connected via the. 18 is a cylinder for raising and lowering the gantry, and both base end and intermediate members 14,1
The gantry 10 is configured to be able to raise and lower itself within a certain angular range by the expansion and contraction of the cylinder 18.

That is, FIG. 1 shows a folded state in which the rear column 12 is fully retracted and the gantry 10 is completely laid down. When the undulating cylinder 18 is extended from this state, the intermediate member 15 is pushed out,
The gantry 10 is erected to the position shown in FIG. Between FIG. 1 and FIG. 2, the front strut 11 rotates by an angle α, and this angle α becomes the gantry's self-lifting range by the lifting cylinder 18. Further, during normal pile driving work, the tip member 16 is further pulled out from the state shown in FIG. 2 to fully extend the rear column 12, resulting in the high gantry state shown in FIG. 3. Pulling out the tip member 16, that is, setting it in the high gantry state, can be performed by winding up the leader hoisting wire on the same winch (none of which is shown) with the leader laid down on the ground.

In addition, in the folded state of the gantry shown in FIG.
It is pinned via pins 9, 20, and 21. Also,
In the state shown in Figure 3, the middle and tip members 15 and 16
are fixed with pins through pin holes 20 and 22.

23 is the gantry sheave, the gantry peak part,
That is, it is provided at the connecting point of the front and rear columns 11 and 12 at the tip, and the wire pulled out from the leader hoisting winch passes through this gantry sheave 23 to the leader hoisting sheave block (not shown).
guided by.

Therefore, a sheave bracket 24 is provided protruding rearward from the gantry peak portion where the gantry sheave 23 is provided, and this sheave bracket 24
A sheave 25 for attaching and detaching the counterweight (hereinafter referred to as a rear sheave) is provided at the rear sheave. This rear sheave 25 protrudes significantly rearward from the counterweight mounting table 9 in the gantry folded state shown in FIG. It can be lifted from the ground. In other words, by arranging the sheave 25 for hoisting the counterweight behind the gantry peak portion in this manner, a rear hoisting position that does not interfere with the weight 8 when attaching and detaching the weight is ensured.

However, if the rear limit of the weight hanging position is set sufficiently rearward as described above, the weight 8 is placed on the mounting table 9.
The front limit lifting position for raising and lowering the weight 8 will also shift rearward, making it impossible to vertically raise and lower the weight 8. Therefore, in this device, a pin hole 26 is also provided at a predetermined length position in the middle of the tip member 16 in the gantry rear column 12 for adjustment during this period, in other words, in order to increase the amount of longitudinal movement of the rear sheave 25. By inserting a pin 28 into this pin hole 26 and a pin hole 27 provided at the upper end of the intermediate member 15, as shown in FIG. It is configured to be fixed.

FIG. 4 shows a state in which the intermediate member 15 of the rear column 12 is pushed out to the maximum extent, that is, in a state in which the gantry is in its own upright position, and the leader hoisting wire (not shown) is wound around the gantry.
0 is further erected, and the tip member 16 is pinned at the intermediate predetermined length position before reaching the high gantry state shown in FIG. 3. In this state, the rear end of the rear sheave 25 is located on a vertical line a passing through the suspension center of the counterweight 8.
Therefore, in this state, the weight 8 can be lifted vertically by fixing the wire 7 from the winch 6, which has been passed through the gantry sheave 23 and the rear sheave 25 in advance, to the counterweight 8 and winding it up ( (Situation shown in Figure 5). In other words, the position of the sheave 25 and the intermediate drawer fixing position of the tip member 16 are set so that the rear end of the rear sheave 25 is located on the vertical line a when the intermediate member 15 is pushed out to the maximum extent. It is.

At this time, the upright angle x of the front strut 11 is the second
This is larger than the upright angle x' when the tip member 16 is fully contracted, as shown in the figure. In other words, the gantry 10 starts to move backward from a position where the front column 11 is more vertical. In this way, by setting the lodging start position of the gantry 10 at a position closer to the vertical, the gantry 10 is lowered by the same angle α as when lowering the gantry 10 from the state shown in FIG. 2 to the state shown in FIG. In the state shown in FIG. 6, the backward movement stroke S of the counterweight 8 (rear sheave 25) is larger than the movement stroke S' when the counterweight 8 (rear sheave 25) is laid down from the state shown in FIG. 2 to the state shown in FIG. At the position shown in FIG. 6, the counterweight 8 can be lowered to the ground without interfering with the mounting table 9.

Further, the counterweight 8 can be attached by the reverse procedure to the above.

As described above, the present invention has a sheave 25 for attaching and detaching the counterweight at the rear position of the gantry peak.
By providing this, the rear limit lifting position of the counterweight 8 is set to a position where it does not interfere with the weight mounting table 9, and at the same time, the self-lowering start position (self-raising end position) of the gantry 10 is set to a position closer to the vertical position. Counterweight 8 by
The amount of movement back and forth is large. By doing this, there is no need to use a separate crane or auxiliary equipment such as hydraulic cylinders or equalizers to increase the amount of back-and-forth movement.
The counterweight 8 can be easily attached and detached completely by oneself.

[Brief explanation of the drawing]

The figures show an embodiment of the present invention; Fig. 1 is a side view showing the gantry in the folded state, Fig. 2 is in the self-standing state, Fig. 3 is a side view showing the high gantry state, and Figs. 4 to 6 are side views showing the counterweight state. FIG. 3 is a side view showing the attachment/detachment process. 1...Base machine, 6...Winch, 8...
Counterweight, 9... Counterweight mounting table, 10... Gantry, 11... Front column of gantry, 12... Rear column, 14... Base end member of rear column, 15... Intermediate member, 16 …
...Same tip member, 18...Luffing cylinder, 2
3... Gantry sheave, 24... Sheave bracket, 25... Sheave for attaching/detaching counterweight, 2
6... Pin hole of the member for fixing the intermediate drawer position of the tip member, 27... Pin hole of the intermediate member, 28... The same pin.

Claims (1)

[Scope of utility model registration request] A weight platform is provided at the rear end of the base machine, a counterweight is removably installed on the weight platform, and a movable gantry is provided at the front of the counterweight in the base machine. is the front strut and
A telescoping rear column consisting of three stages of members at the base, middle, and tip connected in a telescopic manner, and a gantry sheave installed at the gantry peak where the tips of both the front and rear columns are connected. and a gantry hoisting cylinder provided between the proximal end member and the intermediate member of the rear column, in which the counterweight is lifted using the gantry and a winch mounted on the base machine. A counterweight attachment/detachment device for attaching/detaching a counterweight, in which a sheave bracket is provided protruding rearward from the gantry peak portion, and a sheave for attaching/detaching the counterweight is provided in the sheave bracket through which a wire pulled out from the winch is passed. On the other hand, pin holes are provided in both the intermediate and tip members of the rear column of the gantry to fix the tip member to the intermediate member at an intermediate position between fully extended and fully retracted, and the sheave for attaching and detaching the counterweight is attached to the tip member. When the gantry is fixed at the intermediate position and the gantry is upright, the counterweight can be raised and lowered above the weight mounting table, and when the gantry is folded down, the counterweight can be raised and lowered behind the weight mounting table. A counterweight attachment/detachment device for a crane, characterized in that it is configured as follows.