JP3414867B2 - Wire telescopic mechanism of simultaneous telescopic boom - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a simultaneous telescopic boom used for a work vehicle having a telescopic boom, such as a mobile crane or a high work vehicle. The present invention relates to a wire stretching mechanism. 2. Description of the Related Art A work vehicle having a telescopic boom such as a mobile crane or a high-altitude work vehicle is provided with a simultaneous telescopic boom using a wire telescopic mechanism in order to reduce the weight of the telescopic boom. -Is often used. An example of this kind of simultaneous telescopic boom will be described with reference to FIG. [0003] Reference numeral 1 denotes a base-side boom, 2 denotes an intermediate boom which is provided so as to be extendable with respect to the base-side boom 1, and 3 denotes a tip which is provided so as to be expandable and contractible with respect to the intermediate boom 2. Side booms 4 and 4 are telescopic cylinders interposed between the base boom 1 and the intermediate boom 2, and the rod end 4a is attached to the base end of the base boom 1. The rod-side end of the cylinder 4b is connected to and attached to the base end of the intermediate boom 2. [0004] Reference numeral 5 denotes an extension pulley attached to both ends of the front end portion of the intermediate boom 2. 6, a central portion thereof is locked by a locking member 7 fixed to the base end portion of the distal side boom 3;
The pulley 5 is guided by the elongating pulley 5 in a U-shape, and is fixed to the distal end of the base side boom 1 with a cable end stopper 8 integrally attached to both cable ends 6a. It is a wire rope for extension. Reference numeral 9 denotes a pulley for reduction mounted on both sides of the rod-side end of the cylinder 4b. The center portion 10 is locked by a locking member 11 fixed to the base end portion of the distal end side boom 3 and then guided in a U-shape by the reduction pulley 9 so as to be guided at both ends thereof. The cable end stopper 12 integrally attached to 10a is fixed to the distal end of a wire locking rod 1a extending from the proximal end of the proximal side boom 1 and reduced. Wire rope. The extension pulley 5 and the extension wire rope 6 constitute an extension wire extension mechanism a, and the reduction pulley 9 and the reduction wire rope 10 constitute a reduction wire extension mechanism b. Each is configured. In the simultaneous telescopic boom constructed as described above, telescopic movement of the intermediate boom 2 with respect to the base side boom 1 by the telescopic cylinder 4 is carried out via extension and contraction wire telescopic mechanisms a and b. To the distal end side boom 3 and the distal end side boom 3
Is driven simultaneously with the intermediate boom 2, so that there is no need for a telescopic cylinder for driving the distal boom 3 to expand and contract, and the telescopic boom can be reduced in size and weight. It has. However, the service life of a telescopic wire rope used in a wire telescopic mechanism of a simultaneous telescopic boom of this type is generally folded in a U-shape by a telescopic pulley. In this case, the radius of curvature of the wire rope, that is, the magnitude of the curvature of the wire rope with respect to the wire diameter, is greatly affected. The life is extended when the radius of curvature is large, and the life is shortened when the radius of curvature is small. On the other hand, the diameter of the telescopic pulley, which determines the radius of curvature of the wire rope, cannot be made too large due to the restriction on the size of the telescopic boom, and the life of the telescopic wire rope is relatively short. There was a problem. Therefore, the telescopic wire rope is constituted by two or more wire ropes, whereby the diameter of each wire rope is reduced, thereby simultaneously extending the life of the wire rope. Booms have been put into practical use in recent years,
In this case, as the number of wire ropes increases, a space for arranging the telescopic pulley and a space for fixing the cable ends are required, and there is a problem that the telescopic boom becomes large. SUMMARY OF THE INVENTION In view of the above problems, the present invention provides an extension wire rope composed of two or more wire ropes to extend the life of the wire rope, while reducing the space required for disposing the extension pulley. It is an object of the present invention to provide a simultaneous telescopic boom wire expansion / contraction mechanism in which the locking space at the cable end is made as small as possible to reduce the size and weight of the telescopic boom. In order to achieve the above object, a wire telescopic mechanism of the simultaneous telescopic boom of the present invention is constituted as follows. That is, in the wire expansion / contraction mechanism of the simultaneous expansion / contraction boom, the extension wire rope is constituted by two or more wire ropes provided side by side, and the pulley groove of the extension pulley is provided together with the extension wire rope. A wide pulley groove so that it can be folded back, and at least one of the cable ends of the wire rope for elongation is collectively fixed to a single cable end stopper, and a proximal end bracket is provided. It is characterized in that it is configured to be locked at the proper position of the beam or at the base end of the front side boom. The simultaneous telescopic boom wire extension mechanism of the present invention constructed as described above comprises two or more wire ropes in which the extension wire ropes are provided in parallel with each other. The diameter of the wire rope can be reduced, and the life of the wire rope can be prolonged accordingly. Also,
Since the extension pulleys for guiding two or more wire ropes back are formed with wide pulley grooves so that the wire ropes can be turned back together, the pulleys need not be provided with a plurality of extension pulleys. Can be configured to be small. In addition, the cable ends of two or more extension wire ropes are collectively fixed to a single cable end stopper and locked at a proper position on the proximal end boom or at the proximal end of the distal end boom. As a result, the installation space for the wire end locking portion of the wire rope is smaller than that in which the cable end stopper is fixed to the cable end of each wire rope and individually locked to the boom. It can be made smaller. For this reason, while the extension wire rope is constituted by two or more wire ropes and is a simultaneous expansion / contraction hood with a greatly extended life, the arrangement space of the extension pulley and
The locking space at the cable end can be made as small as possible, and the telescopic boom can be reduced in size and weight. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of a simultaneous telescopic boom wire telescopic mechanism of the present invention will be described with reference to FIGS. The wire expansion and contraction mechanism of the present invention is different from the wire expansion and contraction mechanism described in the prior art in that the configuration of the extension wire rope and the accompanying engagement of the extension pulley and the cable end of the extension wire rope. Since only the configuration is different, the following description focuses on this difference. Reference numeral 13 denotes an extension wire rope. In this embodiment, the extension wire rope is constituted by two small-diameter wire ropes provided side by side. Reference numeral 14 denotes an extension pulley provided on both sides of the distal end portion of the intermediate boom 2. The pulley groove 14a is formed of a wide pulley groove so that the two extension wire ropes 13 can be folded back together. Have been. Numeral 15 is a latch provided at the base end of the distal side boom 3 for latching the central portion 13a of the two extension wire ropes 13. The groove 15a is also formed of a wide locking groove so that the two extension wire ropes 13 can be locked together. Reference numeral 16 denotes a cable end stopper for locking the cable ends 13b, 13b of the two extension wire ropes 13 to the distal end of the base side boom 1 at a time. The cable end stopper 16
Are the cable ends 13 of the two wire ropes 13 as shown in FIG.
a caulking portion 16a for caulking and fixing the b and 13b together in a side-by-side state; and a screw portion 16b for adjusting and locking to a wire locking member 17 provided at the distal end portion of the base side boom 1. It is composed of 18 is a fixing nut. Reference numeral 19 denotes a reduction wire rope. In this embodiment, similarly to the extension wire rope 13, two small diameter wire ropes are provided in parallel with each other. 20
Are pulleys for reduction provided on both sides of the end of the telescopic cylinder 4 on the rod side, and the pulley grooves 20a have two wire rods for reduction.
The pulleys 19 are configured with wide pulley grooves so that they can be folded back together. Numeral 21 is a latch provided at the base end of the distal side boom 3 for latching the central portion 19a of the two reduction wire ropes 19. The groove 21a is also formed of a wide locking groove so that the two reduction wire ropes 19 can be locked together. Reference numeral 22 denotes a distal end of a wire locking rod 1a extending from the base end of the base end side boom 1 by collectively connecting the respective cable ends 19b, 19b of the two reduction wire ropes 19. It is a cable end stop metal fitting for locking to. The cable end stopper 22 has a caulking portion 22a for integrally caulking and fixing the cable ends 19b of the two wire ropes 19 similarly to the cable end stopper 16 of the extension wire rope 13. And a screw portion 22b which is tensioned and adjustable at the tip of the wire locking rod 1a. It should be noted that the above-mentioned two elongating wire ropes 13 are used.
And an extension wire wire provided at the distal end of the intermediate beam 2.
The extension wire pulling mechanism A for extending the pull-up guide 13 and the extension wire pulling mechanism 14 for guiding the extension, and the two reduction wire ropes 19 for reduction are used.
And a reduction pulley 20 provided at the rod-side end of the telescopic cylinder 4 for guiding the reduction wire rope 19 back to form a reduction wire expansion mechanism B. Next, the operation will be described. The telescopic cylinder 4 may be driven to telescopically drive the simultaneous telescopic boom. As a result, the intermediate boom 2 expands and contracts with respect to the base side boom 1 in the same manner as the conventional simultaneous expansion and contraction boom. Is transmitted to the distal end side boom 3 and the distal end side boom 3 is driven to expand and contract simultaneously with the intermediate boom 2. At this time, since the extension wire rope 13 and the reduction wire rope 19 are both composed of two small-diameter wire ropes, the pulley for expansion and contraction is reduced by the reduced diameter of the wire. Even if the diameter of 14 and 20 is the same,
The radius of curvature of the loop can be increased, and the life of the wire rope can be extended. Each of the pulley grooves of the extension pulley 14 and the reduction pulley 20 is formed of a wide pulley groove so that two wire ropes can be folded back in a state of being attached to each other. The arrangement space of the pulleys can be smaller than when the pulleys are provided side by side, so that the telescopic boom can be reduced in size and weight. The cable ends of the extension wire rope 13 and the reduction wire rope 19 are fixed to a single cable end stopper 16 or 22 by integrally fixing the cable ends of the two wire ropes. Since it is designed to be locked to the end-side boom, a cable-end engaging member is fixed to the cable-end of each wire rope and the cable-end engaging member is individually locked to the boom. The space required for the stop is small, and the telescopic boom can be reduced in size and weight. Next, another embodiment of the cable end stopper for locking the cable ends of the telescopic wire ropes 13 and 19 to the base side boom 1 will be described with reference to FIGS. First, FIG.
The embodiment shown in FIG. 5 will be described. 23 is 2
It is a cable end stopper which is integrally fixed by caulking such that the wire ropes are placed side by side. Reference numeral 24 denotes a holding member for fixing the cable end stopper 23 to a wire engaging member 25 provided at the distal end of the base end side boom 1. The holding member 24 is provided with the cable end stopper 23. In a state where the shoulder 23a is in contact with the support 25a of the wire locking member 25, the positions near the ends of the two wire ropes are pinched and fixed. 26 is a tightening bolt. The cable end stopper thus constructed is required to effectively support the tension acting on the telescopic wire ropes 13 and 19 by the shoulder 23a of the cable end stopper 23 and the bearing 25a of the wire locking member 25. You can do it. Next, the embodiment shown in FIGS. 6 and 7 will be described. Reference numeral 27 denotes a wire insertion hole formed in the wire locking member 28. The wire insertion hole 27 is in the 2
Oval main insertion hole 27a through which two wire ropes can be inserted
And a communication groove 27b continuously provided in the main insertion hole 27a and through which an individual wire rope can be inserted. In order to insert the wire rope into the wire insertion hole 27 configured as described above, the wire rope is first inserted one by one from the communication groove 27b as shown by the chain line in FIG.
In this case, two wire ropes may be accommodated together. As a result, if tension acts on the wire rope, the shoulder 23a of the cable end stopper 23 comes into contact with the end face of the wire locking member 28, and the tension acting on the wire rope is effectively reduced by the wire locking member. 28. In the embodiment described above, the extension wire rope 13 and the reduction wire rope 19 are each provided with two wire ropes.
Although an example in which the wire stretching mechanism is constituted by a wire has been described, the wire extending / contracting mechanism of the present invention is not limited to this, and only the extending wire rope 13 may be constituted by two or more wire ropes. Of course. At that time, the wire
Needless to say, if the number of the loops is two or more, the number of the loops can be appropriately changed as needed. Further, in the above-described embodiment, the example in which the extension pulley 14 is provided on both sides of the distal end portion of the base end side boom has been described. It is. Similarly, the example in which the reduction pulley 20 is provided on both sides of the rod-side end of the telescopic cylinder 4 has been described, but it goes without saying that it may be provided on both sides of the base end of the intermediate boom 2. In the above embodiment, the extension wire rope 13 is fixed to the distal end of the base boom 1 at the rope end, and the reduction wire rope 19 is secured to the distal end of the wire locking rod 1a at the rope end. The above description has been made of an example in which the extension wire rope 13 is used to fix the extension wire rope 13 to the base end of the distal boom 3 and the reduction wire rope to the base end of the distal boom 3. Needless to say, the rope end of the rope 19 may be similarly locked using a rope end fitting. The wire telescopic mechanism of the simultaneous telescopic boom according to the present invention, which is constructed and operated as described above, comprises a wire rope for extension comprising two or more wire ropes. Although the service life is extended, the space for disposing the extension pulley and the space for retaining the cable ends are made as small as possible, thereby achieving the effect of reducing the size and weight of the telescopic boom.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a side view for explaining a wire extension / contraction mechanism of a simultaneous extension / contraction boom of the present invention. FIG. 2 is a plan view illustrating a wire expansion and contraction mechanism of the present invention. FIG. 3 is an explanatory view of a cable end stopper of a telescopic wire rope according to the present invention. FIG. 4 is an explanatory view of another embodiment of the cable end stopper of the present invention. FIG. 5 is a plan view of FIG. 4; FIG. 6 is an explanatory view of another embodiment of the cable end stopper of the present invention. FIG. 7 is a plan view of FIG. 6; FIG. 8 is an explanatory view of a conventional wire extension / contraction mechanism of a simultaneous extension / contraction boom. [Description of Signs] 1 Base end side boom 2 Intermediate boom 3 End side boom 4 Telescopic cylinder 13 Extension wire rope 14 Extension pulley 14a Pulley groove 16 Rope end stopper 19 Wire reduction rod 20 Pulley 20a for reduction Pulley groove 22 Cable end stopper

Claims (1)

(57) [Claims 1] An intermediate boom is inserted in the base side boom.
Distal end side Bed in beam - Simultaneous stretching Bed comprising sequentially telescopically fitted insert the beam - a beam, rod end to the proximal end side Bed - husband arm s - arm to the rod end of the cylinder intermediate Bed A telescopic cylinder connected between the base end boom and the intermediate boom, and an extension pulley provided at the distal end of the intermediate boom or at the cylinder distal end of the telescopic cylinder. And a wire rope for extension in which the cable ends are locked to a proper position of the base-side boom and a base end of the distal-side boom, respectively, and the base end of the intermediate boom or the above-mentioned. An intermediate portion of the telescopic cylinder is folded back and guided by a reducing pulley provided at the rod end of the telescopic cylinder, and its cable ends are locked at appropriate positions of the distal end of the base side boom and the distal end boom. A retractable wire rope, linked to the extension and retraction of the intermediate boom with respect to the base side boom by the telescopic cylinder. The simultaneous extension and contraction boom wire extension and contraction mechanism configured to extend and retract the distal end side boom, wherein the extension wire rope is constituted by two or more wire ropes provided in parallel with each other, and The pulley groove of the extension pulley is formed of a wide pulley groove so that the extension wire rope can be folded back together with the extension wire rope, and at least one of the cable ends of the extension wire rope is collectively formed. A wire extending / contracting mechanism for a simultaneous telescopic boom, which is fixed to a single cable end stopper and locked at a proper position of the proximal boom or at a proximal end of the distal boom. .