JPH0144548Y2 - - Google Patents

Description

[Detailed description of the invention] (a) Industrial application field The present invention relates to a sheave mounting structure that is attached to a multi-stage telescoping boom mounted on an aerial work vehicle, a crane vehicle, etc.

(b) Prior Art As shown in Fig. 4, the conventional sheave mounting structure for a multi-stage telescopic boom consists of welding a boss 02 to the tip of an intermediate boom 01, inserting a shaft 03 into this boss 02, and then inserting a shaft 03 into this boss 02. The sheave 04 was inserted into the sheave 03 and secured with a stop shaft 05.

However, in this structure, when inserting the sheave 04 into the shaft, the sheave 04 cannot be inserted just by pushing it by hand, so it is necessary to hit it with a hammer or the like.

Therefore, there needs to be enough space to hit it with a hammer, and since it cannot be hit with a hammer when tip boom 06 is inserted, sheave 04 cannot be installed, and tip boom 06 must be installed after sheave 04 is installed. I couldn't insert it. Therefore, when inserting the tip boom 06 after attaching the sheave 04 to the intermediate boom 01,
The distance between the tip boom 06 and the intermediate boom 01 must be increased so that the wire attachment material 07 provided at the base of the intermediate boom 01 does not come into contact with the sheave 04 of the intermediate boom 01, and as a result, the intermediate boom 01 is large. There was the problem of becoming a thing.

(c) Purpose of the invention This invention was made to solve the above-mentioned problems, and has a structure in which a sheave can be attached to the tip of the intermediate boom while the tip boom is inserted into the intermediate boom. This eliminates the need to make the boom larger.

(d) Structure of the invention The feature of the invention is that the base boom, intermediate boom, and tip boom can be expanded and retracted by the operation of a hydraulic cylinder and by wires strung around booms installed at appropriate positions on the intermediate boom. In the multi-stage telescopic booms that are freely fitted together, a boss is welded to an appropriate position on the intermediate boom, a collar with a fitting part provided inside is removably inserted into the boss from the outside of the intermediate boom, and the collar is fitted into the intermediate boom. The shaft that rotatably supports the sheave is fitted into the fitting part of the collar from the inside of the intermediate boom, and the shaft and collar are integrated with bolts on the outside of the collar, so that the sheave is moved first. The sheave mounting structure of the multi-stage telescopic boom is such that it can be mounted in the gap between the partial boom and the intermediate boom.

(e) Example The following is an explanation based on an example of the present invention.
1 is a three-stage telescopic boom that is extendable and retractable, and this three-stage telescopic boom 1 is composed of a base boom 2, an intermediate boom 3, and a tip boom 4, which are successively smaller in size.

A hydraulic cylinder 5 for extending and retracting the three-stage telescopic boom 1 is provided in the three-stage telescopic boom 1, and this hydraulic cylinder 5 is pivotally supported at the base of the base boom 2 and the base of the intermediate boom 3. There is.

6, 6 are sheaves provided at the tip and base of the intermediate boom, and the sheave 6 at the tip has one end pivotally supported at the base of the tip boom 4, and the other end mounted forward on the outside of the base boom 2. An elongated wire 7 that is pivotally supported in the direction is spanned. Further, a reduced wire 8 having one end pivotally supported at the base of the tip boom 4 and the other end pivotally supported in the rearward direction outside the base boom 2 is stretched over the base sheave 6.

With the above configuration, each of the booms 2, 3, and 4 expands and contracts as the hydraulic cylinder 5 expands and contracts.

Next, the mounting structure of the sheaves 6, 6 will be explained in detail based on FIG.

Reference numeral 9 denotes a boss welded to the tip of the intermediate boom 3, and a collar 11 with a fitting part 10 provided inside the boss 9 is inserted from the outside of the intermediate boom 3 and fixed with bolts 12, 12 in a removable manner. It has been done.

13 is a sheave 6 around which the elongated wire 7 is stretched.
This shaft 13 is fitted into the insertion portion of the collar 11, and is tightened with bolts 14, 14 on the outside of the collar 11, so that the shaft 13 and the collar 11 are integrated. I have to.

Next, in order to attach the sheave 6, the boss 9 is first welded to the intermediate boom 3.

Next, the front boom 4 is inserted into the intermediate boom 3.
Thereafter, the sheave 6 into which the shaft 13 has been inserted is inserted into the gap between the front boom 4 and the intermediate boom 3 and brought to the position of the boss 9.

Next, insert the collar 11 into the boss 9 and
Align the shaft 13 with the fitting part 10 of
4 and 14, and further tighten the bolts 12 and 12.

By attaching the sheave 6 as described above, the sheave 6 does not come into contact with the wire attachment member 15 shown in FIG. 3, so that the intermediate boom 3 can be made smaller.

(f) Effect of the invention As explained in detail above, the invention connects the base boom, intermediate boom, and tip boom by the operation of a hydraulic cylinder and by wires strung through sheaves installed at appropriate positions on the intermediate boom. , in a multi-stage telescopic boom that is telescopically fitted, a boss is welded to an appropriate position of the intermediate boom, a collar with a fitting part provided inside is removably inserted into the boss from the outside of the intermediate boom, and this A shaft that rotatably supports the sheave on the collar is fitted into the fitting part of the collar from the inside of the intermediate boom, and the shaft and collar are integrated with bolts on the outside of the collar, thereby making it possible to connect the sheave to the collar. By making it possible to install the sheave between the tip boom and the intermediate boom, the sheave can be installed after the tip boom is inserted into the intermediate boom, which prevents the sheave from coming into contact with the wire attachment material. This eliminates the problem of not having one, and the intermediate boom can be made smaller.

[Brief explanation of the drawing]

Fig. 1 is an overall view of a multi-stage telescopic boom equipped with the sheave mounting structure of the present invention, Fig. 2 is a sectional view taken along line A-A in Fig. 1, Fig. 3 is a sectional view taken along line B-B in Fig. The figure is a sectional view of a sheave attachment part of a conventional multi-stage telescopic boom. 2 is a base boom, 3 is an intermediate boom, 4 is a tip boom, 5 is a hydraulic cylinder, 6 is a sheave, 7 and 8 are wires, 9 is a boss, 10 is a fitting part, 11 is a collar, and 13 is a shaft .

Claims (1)

[Scope of utility model registration request] In a multi-stage telescopic boom in which a base boom, an intermediate boom, and a tip boom are telescopically fitted together by the operation of a hydraulic cylinder and a wire stretched over a sheave provided at an appropriate position on the intermediate boom, A boss is welded to the position, a collar with a fitting part on the inside is removably inserted into the boss from the outside of the intermediate boom, and a shaft that rotatably supports the sheave is attached to the collar inside the intermediate boom. The sheave is fitted into the fitting part of the collar, and the shaft and collar are integrated with bolts on the outside of the collar, so that the sheave can be installed in the gap between the front boom and the intermediate boom. Sheave mounting structure in multi-stage telescopic boom.