JPH0449198A - Boom for industrial vehicle - Google Patents

Abstract

PURPOSE:To easily infer looseness of a traction member by mounting a guide member in parallel to a flyboom and providing a measuring device making contact possible with a middle boom in the concerned guide member. CONSTITUTION:At maximum elevation time of a boom 19, a middle boom 5 and a flyboom 7 are once extended, and next in the case of minimum contraction, the boom 7 is placed in a condition of the minimum contraction by its own weight despite looseness of a chain 20. Here, a measuring device 14 is brought into contact with the boom 5 and moved on a guide bar 13 against pressing force of a rubber bush 18 to show a distance L1 from a supporting member 12 to the boom 5. Next, the boom 19 is placed horizontal or less, to once extend the booms 5, 7, and next to the minimum contraction. Here, when the chain 20 is loosened, the boom 7 is not clearly contracted by the amount of this looseness. Accordingly, the amount of the looseness of the chain 20 is inferred by showing a distance L2 from the supporting member 12 to a point end of the boom 5 to be compared with the distance L1.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a boom for an industrial vehicle equipped with a telescoping boom, such as a telescoping boom aerial work vehicle, a boom telescoping crane vehicle, and the like.

[Prior art] In the conventional technology, as shown in FIG.
The boom of an industrial vehicle is composed of three booms: a heath boom 23, a middle boom 24, and a fly boom 25. The extension traction member 26 (usually composed of wire or chain) is a wheel whose one end is fixed to the base end of the fly boom 25 and the other end is fixed to the tip of the middle boom 24. It is fixed to the outside of the tip portion of the base boom 23 via 27. The reduction traction member 28 has one end fixed to the base end of the fly boom 25 and the other end fixed to the base end of the middle boom 24.
9 is fixed to the inside of the tip of the base boom 23. Furthermore, the base end of the cylinder 30 is connected to the base boom 2.
The cylinder rod 31 is fixed to the distal end of a cylinder box 32 whose base end is connected to the base end of the middle boom 24 .

[Problems to be Solved by the Invention] However, the above industrial vehicle boom has a drawback in that it is difficult to check for slack due to elongation of the traction member. Specifically, to check this slack,
The protruding length of the fly boom when the middle boom and fly boom are set to the height line with the boom in the upright position, and when the middle boom and fly boom are set to the height line with the boom in the horizontal or lower position. Measuring the protruding length of the fly boom in the former condition required working at heights, which was dangerous, and required another industrial vehicle.

[Means to solve the problem]

In order to solve the above problems, the present invention has a base boom, a middle boom, and a fly boom, and a cylinder member disposed between the base boom and the middle boom and a traction member connected between the booms. , in an industrial vehicle with a telescopic boom configured to be extendable and retractable, a guide member is attached to the fly boom in parallel with the fly boom;
The present invention provides a boom for an industrial vehicle, characterized in that a measuring device is provided on the guide member so as to be able to come into contact with the middle boom.

[Effect]

In the industrial vehicle boom of the present invention, the measuring device includes:
When it comes into contact with the middle boom when the boom is retracted, it moves and remains stationary at the moved position. Therefore, there is slack in the traction member, and the difference between when the middle boom and fly boom are set to the line with the boom in the upright position and when the middle boom and fly boom are set to the line with the boom below horizontal. If there is a difference in the protruding length of the fly boom, the measuring device is fixed at position 1 when the boom is in its most upright position.
There is a difference between the position of the end of the middle boom when the boom is below horizontal. Based on this difference, it is possible to detect the degree of slack in the traction member.

〔Example〕

Next, embodiments according to the present invention will be described based on the drawings.

In FIG. 5, 31 is a machine base equipped with wheels 37, and 32 is a swivel table installed on the machine base 31 via a rotating body 33 so as to be horizontally rotatable. 36 indicates balance weight,
19 attaches the base end of the bottle 35 to the pillar 34 of the swivel table 32.
It is a telescopic boom that is pivoted so that it can move up and down through the
Reference numeral 3B indicates a cylinder for raising and lowering. In FIG. 1, the base end of the lift cylinder 1 is fixed to the base end of the base boom 2. The cylinder rod 3 of the cylinder 1 is fixed to the tip of the cylinder box 4. A base end of the cylinder box 4 is fixed to a base end of the middle boom 5. One end of the extension chain 6 as a traction member is fixed to the base end of the fly boom 7, and the other end is fixed to the outside of the tip of the base boom 2 via a chain wheel 8 fixed to the tip of the middle boom 5. has been done. Similarly, the reduction chain 9, which also serves as a traction member, has one end fixed to the base end of the fly boom 7, and the other end or the inner end of the heath boom 2 via a chain wheel 10 fixed to the front end of the middle boom 5. Fixed.

The driver's cab 11 is fixed to the tip of the fly boom 7. At the portion of the fly boom 7 that protrudes from the middle boom 9 at the time of drawing, a support member 1 is attached downwardly at the bottom thereof.
A guide bar 3 as a guide member is installed on the support member 12 in parallel to the outside of the middle boom 5 so as not to contact the middle boom 5 in the direction of the proximal end of the pool 7. has been done. Note that the support member 12 can also be attached to another member that moves integrally with the fly boom 7. A measuring device 14 is attached to the guide bar 13 so as to come into contact with the middle boom 7 during the boom dose measurement. More specifically, as shown in FIG. 2 and FIG.
5b is attached. Same as above plates 15a, 15
A relatively large recess 151 and a bolt through hole 152 are continuously provided in the lower plate 15b.
A relatively large recess 153 and a threaded portion 154 to which the bolts 16a, 16b correspond are continuously provided. Even if the collar 17 is fitted into the recesses 151 and 153 and the ports 16a and 16b are tightened all at once, the upper play)1
5a and the lower plate 15b, there is a gap slightly larger than the thickness of the guide bar 13.

Reference numeral 18 denotes a rubber bush which is sandwiched between the upper and lower plates 15a and 15b.By tightening the bolts, the rubber bushings are sandwiched from both sides of the guide bar 13 in the lateral direction with an appropriate pressing force, and the upper and lower plates 15a and 15b are placed on the guide bar 13. Fixed.

Next, the operation of the present embodiment will be explained. base boom 2
The middle boom 5 is extended and contracted into the base boom 2 via the cylinder box 4 by a hydraulic cylinder l whose base end is attached to the base boom 1, and the extension and contraction operation of the fly boom 7 is performed by an extension chain 6 and a reduction chain 9. Further, the process is performed on the middle boom 5. The measuring device 14 has an upper plate 15a and a lower plate 1 due to the presence of the collar 17.
There is a gap between the guide bars 5b, allowing sliding movement along the guide bar 13. Further, the rubber bush 18 is laterally collapsed by tightening the bolts 16a and 16b, and applies an appropriate pressing force to both sides of the guide bar 13. When the measuring device 14 comes into contact with the middle boom 5, it can be pushed and moved, and due to the resistance, even if it is separated from the middle boom 5, its position remains unchanged. As shown in FIG. 4, when the boom 19 is fully erected, if the middle claw 5 and fly boom 7 are once extended and then set to the vertical line, the fly boom 7 will move due to its own weight regardless of the slack of the chain 20. becomes a line. At this time, the measuring device 14 comes into contact with the middle boom 5 and the rubber bush 1
The boom 19 is moved on the guide bar 13 against the pressing force of 8, and the boom 19 is moved below the horizontal position as shown in FIG. Extend the middle boom 5 and fly boom 7, and then make a dosing line. In this case, if the chain 20 is slack, the fly boom 7 will not be fully retracted by this slack.
Therefore, the distance from the support member 12 to the tip of the middle boom 5 indicates L2, and by comparing it with Ll, it is possible to detect the amount of slack in the chain 20.

l! ! FIG. 6 shows a second embodiment, in which a guide bar 40 is marked with scales, and a measuring device is not required when measuring L1 and L2.

In FIG. 7, the measuring device 41 can be stored in the supporting member 42. A hole is provided on the side of the supporting member 42 on the cheno wheel 8 side into which the measuring device 42 can be inserted, so that the measuring device 41 can be stored when measurement is not required. If it is exposed outside, it is possible to prevent the measurement device 41 from becoming immovable due to paint or the like.

In addition, although the above explanation is based on a case where the boom is composed of three boom members: a base boom, a middle boom, and a fly boom, it is also possible to use a boom composed of four or more boom members. be.

[Effects of the Invention] As detailed above, the present invention provides a guide member and a measuring device, thereby making it possible to easily detect slack in the traction member, and making significant changes to the conventional device. It has an extremely excellent effect that it can be implemented with a simple structure without any problems.

[Brief explanation of the drawing]

Fig. 1 is a side sectional view of a boom showing the first embodiment, Fig. 2 is an enlarged front view of main parts of the measuring device of the first embodiment, and Fig. 3 is a sectional view taken along line A-A in Fig. 2; Figure 4 is a side view showing the industrial vehicle when the boom is upright, Figure 5 is a side view showing the industrial vehicle when the boom is below horizontal, and Figures 6 and 7 are side views of main parts showing other embodiments. 8 are side sectional views of the conventional technology. Base boom Middle boom Fly boom support member Guide bar constant device・----2 −・−1111−・−5 ・・−・−7

Claims (1)

[Claims] An industrial vehicle with a telescopic boom, which has a base boom, a middle boom, and a fly boom, and is configured to be extendable and retractable by a cylinder member disposed between the base boom and the middle boom, and a traction member connected between the booms. A boom for an industrial vehicle, characterized in that a guide member is attached to the fly boom in parallel with the fly boom, and a measuring device is provided on the guide member so as to be able to come into contact with the middle boom.