JPH0233636B2 - SHARYOGATAKUREENNOJIBUKAKUNOSOCHI - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a vehicle-type crane such as a truck crane equipped with a jib, and more particularly to a storage device for the jib.

Vehicle-type cranes such as truck cranes are generally equipped with a jib. This jib is extended to the tip side of the boom during use, and by supplementing the length of the boom, it is possible to expand the working range of the crane and ensure a high lifting height for the lifted load. On the other hand, when not in use, the boom is normally supported and stored along the bottom surface of the boom, so that it does not interfere with crane operations using only the boom.

By the way, in the case of such a jib, it is desirable to make its length as long as possible in order to expand the above-mentioned working range and lifting height. However, if the jib is made too long, a problem arises in that the tip of the jib comes into contact with the undulation cylinder that makes up and down the boom when it is stored. For this reason, the length of the jib is limited to the length from the tip of the boom to the connection position between the tip of the luffing cylinder and the boom, and there has been a problem that a longer length cannot be secured.

This invention was made based on these circumstances, and its purpose is to provide a jib for a vehicle-type crane that can store the jib with sufficient length without interfering with the hoisting cylinder. The purpose of the present invention is to provide a storage device.

That is, in this invention, shafts are provided protruding from both sides of the tip of the boom, and both fork recesses at the base end of the jib are fitted to these shafts, and retainers for preventing the shaft from coming off are attached to and removed from both fork recesses. The jib can be extended and retracted by rotating the jib about the axis;
The length between the position of the stopper in one of the fork recesses and the bottom of this fork recess is formed to be longer than the other by a predetermined amount, and the outside of this bottom surface is notched in the bottom of the other fork recess to allow the shaft to protrude. The jib is characterized by forming a relief part for letting the end side escape, and when storing the jib, the jib is tilted diagonally with respect to the boom, and the jib is stored avoiding the above-mentioned undulation cylinder.

An embodiment of the present invention will be described below with reference to FIGS. 1 to 7.

Figure 1 shows a truck crane, 1 is the car body,
2 is a swivel base, 3 is an extendable boom, 4 is a sheave at the tip of the boom 3, 5 is a luffing cylinder, 6 is a cab for traveling, and 7 is a cab for crane work.

A jib 8 is stored in the lower surface of the boom 3. This jib 8 is detachably supported by supports 9 and 10 attached to the bottom surface of the boom 3, 11 is a sheave at the tip of the jib 8, and 12 is a sheave for the jib 8 attached to the side of the boom 3. Auxiliary wire 1
The stopper 3 and 14 are guides for the auxiliary wire 13.

The tip end 3a of the boom 3 has shafts 15, 15 protruding from both sides thereof, and these shafts 15, 15 are used for extending and storing the jib 8. That is, the base end 16 of the jib 8 is configured such that the tip 3a of the boom 3 can be loosely fitted therein, and the base end 16 is configured with a pair of forks 17a, 17b. These forks 17a, 17b are formed by fork recesses 18a, 18b, respectively.
5 can be removably fitted.

Also, on the tip sides of both forks 17a and 17b, a retaining pin 19 is provided as a retainer, respectively.
Nineteen pin holes 20, 20 are formed, and these retaining pins 19, 19 prevent the shafts 15, 15 from coming off.

In this embodiment, the form recesses 18a, 18b are formed as shown in FIGS. 2 and 3.
For example, the distance l ₁ between the pin hole 20 in one of the fork recesses 18a and its bottom surface is set longer than the distance l ₂ of the other fork recess 18b, so that the shaft 15 can be freely moved in one of the fork recesses 18a. It is now ready to mate.

In addition, the bottom surface of the other fork recess 18b is provided with a relief part A formed by cutting out the outer part thereof.
, so that the protruding end side of the shaft 15 can escape.

Note that 21 is a sheave block attached to the tip of the tip end 3a of the boom 3, and it goes without saying that the bottom surfaces of both fork recesses 18a and 18b are positioned on the same reference line X.

In addition, when the jib 8 is stored along the lower surface of the boom 3 as shown in FIG.
15 is set to be automatically attached and detached by the expansion and contraction of this boom 3.

According to an embodiment with such a configuration, the first
Since the jib 8 is in the retracted state as shown in the figure,
When extending this jib 8, first
are contracted to a minimum, and the shafts 15, 15 are fitted into the fork recesses 18a, 18b of the jib 8, and the retaining pins 19, 19 are inserted into the pin holes 20, 20 of these fork recesses 18a, 18b. Then, by letting out the auxiliary wire 13, the auxiliary wire 13 is guided and connected to the stopper 12 via the sheave 21 at the tip of the boom 3. Thereafter, after releasing the support of the jib 8 from the supports 9 and 10, the auxiliary wire 13 is reconnected to the tip of the jib 8 and wound up to rotate the jib 8 toward the tip of the boom 3, and the third As shown in the figure, the extension of the jib 8 is completed. In FIG. 3, 22 is a tension rod that holds the jib 8, and 23 is a jib hook.

On the other hand, when retracting the jib 8 from the extended state, the auxiliary wire 13 is connected to the stopper 12 via the sheave 11 at the tip of the jib 8, as in the case of the above-described extension, and then Remove the tension rod 22 and attach the auxiliary wire 1.
While letting out the boom 3, the jib 8 is rotated toward the boom 3 using its own weight as shown in FIG. Thereafter, the pin 19 in the one fork recess 18a of the jib 8 is removed, and the auxiliary wire 13 is wound up again, so that the jib 8 is brought close to the lower surface of the boom 3. At this time, the retaining pin 19 in the fork recess 18a is removed, and since the fork recess 18a is longer than the other, the jib 8 is tilted diagonally due to its own weight, and the fork recess 18a is in an oblique position due to its own weight. Since the tool 12 is attached to the side of the boom 3, the jib 8 can be more reliably tilted and stored on the underside of the boom 3. After that, the jib 8 is supported by the supports 9 and 10 and the jib 8 is Complete storage.

Therefore, according to the above embodiment, since the jib 8 can be stored tilted, even if the jib 8 is long as shown in FIG. Lifting cylinder 5
It can be stored to avoid. As a result, a sufficient length of the jib 8 can be ensured, and the working performance of the crane can be significantly improved.

Moreover, such an effect is caused by one of the fork recesses 1.
Since the position of the retaining pin 19 in 8a and the length l ₁ to the bottom thereof are longer than the other l ₂ , the structure is very simple and very suitable for implementation. It is something.

Furthermore, when the jib 8 is tilted, since the relief part A is formed on the bottom surface of the other fork recess 18b, the protruding end side of the shaft 15 is tilted by the bottom of the fork recess 18b, as shown in FIG. There are no restrictions and the jib 8 can be easily tilted, resulting in excellent workability.

Furthermore, since the jib 8 is stored diagonally, the tip of the jib 8 can be positioned above the lower surface of the boom 3, as shown in FIG. 1, and visibility from the operating cab 7 can be improved. It also has advantages.

Furthermore, when the jib 8 is extended, the bottoms of both fork recesses 18a and 18b are positioned on the same reference line It is extended so that its axis coincides with the axis.

Note that the present invention is not limited to the above embodiment. For example, as shown in FIGS. 8 and 9, if a guide 23 for guiding the storage of the jib 8 is attached to the lower surface of the boom 3, the jib 8 can be stored diagonally more easily.

Furthermore, the configuration of the retainer is not limited to the one using the retainer pin 19, and can be modified in various ways.

The present invention is applicable not only to truck cranes but also to vehicle-type cranes having a dual-purpose driver's cab for both traveling and crane work.

As explained above, in this invention, the jib is stored obliquely along the lower surface of the boom, so even if the jib is long, it will not interfere with the hoisting cylinder. Therefore, sufficient length of the jib can be ensured, greatly improving crane performance, etc.
It has excellent effects.

[Brief explanation of drawings]

1 to 7 show one embodiment of the present invention, in which FIG. 1 is a side view of a truck crane, FIG. 2 is a partially sectional plan view of the base end of the jib, and FIG. A side view of the proximal end portion from the direction in the figure, No. 4
The figure is a side view of the jib showing the extended state, Figures 5 and 6 are diagrams illustrating how the jib is stored, Figure 7 is a bottom view partially showing the base end of the jib when it is stored, and Figure 8 is a side view of the jib showing the extended state. 9 shows another embodiment, FIG. 8 is a bottom view of the boom, and FIG. 9 is a diagram explaining the action of the guide. 3...Boom, 5...Luffing cylinder, 8...Jib, 15...Axle, 16...Fork, 18a, 1
8b...Fork recess, 19... Retaining pin (retainer), A... Relief part.

Claims (1)

[Claims] 1. An extendable boom is provided so as to be able to be raised and lowered by a hoisting cylinder, and shafts are provided protruding from both sides of the tip of the boom, and both fork recesses at the base end of the jib are fitted to these shafts, and the above-mentioned A retainer that prevents the shaft from coming off is detachably provided in both fork recesses, and by rotating the jib around the shaft, the jib can be extended from the tip of the boom and can be extended along the underside of the boom. In a vehicle-type crane that is designed to be retracted, the length between the position of the retainer in one of the fork recesses and the bottom of this fork recess is formed to be longer than the other by a predetermined amount, and the length of the retainer in the bottom of the other fork recess is A jib for a vehicle type crane, characterized in that the outside of the bottom surface is cut out to form a relief part for letting the protruding end side of the shaft escape, and when stored, the jib is tilted diagonally with respect to the boom and stored while avoiding the hoisting cylinder. storage device.