JPH0515516Y2 - - Google Patents

Description

[Detailed description of the invention] (Field of industrial application) This invention includes an outer boom, an intermediate boom telescopically inserted into the outer boom, and an inner boom telescopically inserted into the intermediate boom. , a telescopic hydraulic cylinder having a piston rod distal end connected to a base end of the outer boom between the outer boom and the intermediate boom, and a telescopic hydraulic cylinder having a piston rod side end connected to the base end of the intermediate boom; In a telescopic boom, the telescopic boom is equipped with an extension synchronization device and a contraction synchronization device for extending and retracting the inner boom relative to the intermediate boom in synchronization with the telescoping movement of the intermediate boom relative to the outer boom by the telescoping hydraulic cylinder. The present invention relates to a pulley arrangement structure, particularly to a pulley arrangement structure for a reduction tuning device.

(Prior Art) This type of telescoping boom is provided with a pair of left and right boss fittings protruding inwardly from the side walls of the intermediate boom, on the left and right side walls of the base end of the intermediate boom. The telescopic hydraulic cylinder has a pair of left and right ear shafts that extend in the radial direction of the cylinder and have blind holes that open at the extending ends at the left and right positions of the piston rod side end of the cylinder. A pair of left and right ear shafts are provided, the dimension between the extending ends being slightly smaller than the inner dimension between the pair of left and right boss fittings, and the base end of the intermediate boom at the end on the piston rod side of the cylinder of the telescopic hydraulic cylinder. The pair of left and right ear shafts are positioned between the left and right boss metal fittings, and a pin is inserted between the corresponding boss metal fittings and the blind hole of the ear shaft.
Pulleys around which the wire rope of the reduction tuning device is wound are rotatably fitted onto the pair of left and right ear shafts via rolling bearings, respectively.

(Problems with the prior art) The pulley externally fitted onto the ear shaft via a bearing,
In order to prevent the bearing from coming off the pulley, a bearing flange is provided that engages with the outer edge of the end face of the bearing.

For this reason, in the conventional pulley support structure,
It was necessary to arrange the pulley so that the outer end (outer end of the bearing flange) of the pulley externally fitted onto the ear shaft via the bearing was located inside the extending end of the ear shaft. This is because if the outer end of the pulley fitted onto the ear shaft protrudes beyond the extending end of the ear shaft, the left and right ear shafts can be fitted between the left and right boss fittings at the base end of the intermediate boom. This is because the telescopic hydraulic cylinder cannot be incorporated into the telescopic boom.

Therefore, the amount of extension of the ear shaft must be increased accordingly, resulting in a problem that the width of the telescopic boom becomes larger.

This idea allows the outer end (bearing flange) of the pulley fitted on the ear shaft to protrude beyond the extending end of the ear shaft, but it also allows the telescopic hydraulic cylinder to be placed inside the telescopic boom. The object is to provide a novel pulley arrangement structure that can be incorporated.

(Means for Solving the Problems) In order to achieve the above object, the arrangement structure of the pulleys in the telescopic boom of the present invention is such that the outer end of each bearing is located approximately at the extending end of the corresponding ear shaft. A bearing flange for positioning the bearing of the pulley fitted externally to the ear shaft through this bearing is positioned outside the extending end of the corresponding ear shaft. In addition, the bearing flange is provided with a part of the lug shaft in order to position each lug shaft of the telescopic hydraulic cylinder between the boss fittings in a state in which each of the pulleys is fitted onto the corresponding lug shaft via a bearing. A notch is provided for allowing the inner end of the boss metal fitting to pass through.

(Function) According to the above configuration, the outer end portion (bearing flange) of the pulley can be arranged to protrude beyond the extending end of the ear shaft, so that the amount of extension of the ear shaft can be reduced accordingly. When installing the telescopic hydraulic cylinder into the telescopic boom, the boss metal fittings can be passed through the notches in the bearing flange at the outer end of the pulley, so the left and right ear shafts can be connected to the left and right bosses at the base end of the intermediate boom. It can be fitted between metal fittings.

(Example) Hereinafter, an example of the arrangement structure of pulleys in the telescopic boom of this invention will be described based on FIGS. 1 to 3.

In FIG. 1, 1 is an outer boom, 2 is an intermediate boom that is telescopically inserted into the outer boom 1, and 3 is an inner boom that is telescopically inserted into the intermediate boom 2. The telescopic hydraulic cylinder 4 inserted between the outer boom 1 and the intermediate boom 2 is a double-acting hydraulic cylinder equipped with a cylinder 5 and a piston rod 6. It is fixed to the base end of the boom 1, and the piston rod side end of the cylinder 5 is fixed to the base end of the intermediate boom 2, and is arranged along the telescopic axis of the three-stage simultaneous telescopic boom. At the opposite end of the cylinder 5 from the piston rod,
A support roller 7 that rolls into contact with the bottom plate b of the inner boom 3
A roller 8 is provided which rolls into contact with the top plate a of the inner boom 3, and regulates the position of the end of the cylinder 5 on the side opposite to the piston rod within the three-stage simultaneous telescopic boom. A spacer 9 is disposed at the base end of the inner boom 1 so that its lower surface is close to the upper side of the cylinder 5 of the telescopic hydraulic cylinder 4. This spacer 9 is located on the end of the cylinder 5 on the side opposite to the piston rod when the three-stage simultaneous telescopic boom is fully extended, and restricts upward movement of that end. A pair of left and right ear shafts 10, 10 extending laterally from the longitudinal center line of the telescoping hydraulic cylinder 4 are provided at the end of the cylinder 5 on the piston rod side. The ear shafts 10, 10 include the ear shaft 1.
Blind holes 11, 11 are provided concentrically with the ear axes 10, 10 from the outer ends of the ear shafts 10, 10. The dimensions between the respective outer ends of the left and right ear shafts 10, 10 are the boss metal fittings 1 provided on the left and right side plates c, c of the intermediate boom 2.
2, 12, and after aligning the blind holes 11, 11 of the ear shafts 10, 10 with the pin holes 13, 13 of the boss fittings 12, 12, the pin 14, 14 is inserted from the outside of the boss fittings 12, 12, thereby fixing the piston rod side end of the cylinder 5 to the intermediate boom 2. 15, 15 are C-shaped retaining rings provided in pin holes 13, 13 near the outer ends of the boss fittings 12, 12 to prevent the pins 14, 14 from coming out. A pulley 1 of a reduction tuning device is attached to the ear shafts 10, 10.
6 and 16 are supported via bearings 17 and 17. The pulleys 16, 16 have bearings 17, 1
Bearing bosses 18, 18 receiving 7 and bearings 1 received in bearing bosses 18, 18
Bearing flange 1 for positioning 7 and 17
9, 19, and a C-shaped retaining ring 20 for preventing the bearings 17, 17 received in the bearing bosses 18, 18 from coming off.

The bearings 17, 17 have a sufficiently large width dimension to rotatably support the force acting on the pulleys 16, 16. Therefore, the width dimension of the bearing mounting portion of the pulleys 16, 16 is smaller than that of the pulleys 16, 16. 16
It is considerably larger than the width of the outer edge of the .

The ear shafts 10, 10 are provided with bearings 17, 17.
It has the same extension amount as the width of the ear shaft 10,
Bearing 1 attached to pulley 16, 16 to 10
When 7 and 17 are externally fitted, the outer ends of the ear shafts 10 and 10 are positioned inward from the widthwise outer ends of the pulleys 16 and 16 by the thickness of the bearing flanges 19 and 19. The bearing flanges 19, 19 of the pulleys 16, 16 have ear shafts 10, 10.
After attaching the pulleys 16, 16 to the ear shafts 10, 1
0 between the inner ends of the boss fittings 12, 12, when the telescopic hydraulic cylinder 4 is fitted from the tip side or base end side of the intermediate boom 2,
A notch 21, 21 is provided through which 2 passes. For this purpose, the notches 2 provided in the bearing flanges 19, 19 by rotating each pulley 16, 16
Bearing flange 1
It became possible to fit the left and right boss fittings 12, 12 through the notches 21, 21 of 9, 19, and the ear shafts 10, 10 of the telescopic hydraulic cylinder 4 were provided at the base end of the intermediate boom 2. Boss metal fittings 12, 12
It can be attached to. Ear axis 10,
10 is fixed to the boss metal fittings 12, 12,
The inner ends of the boss fittings 12, 12 are bearings 17, 1
The bearing 17,1 is located close to the outer end in the width direction of 7.
7 from slipping out from the ear shafts 10, 10. 22 is a hollow rod disposed below the telescopic hydraulic cylinder 4 along the longitudinal axis of the telescopic hydraulic cylinder. The tip of this rod 22 is supported by a support roller 23 that rolls into contact with the bottom plate b of the inner boom 3, and is rotatably or slidably engaged below and on both sides of the cylinder 5 of the telescopic hydraulic cylinder 4. Combined guide tool 2
It is held by 4. 25 is intermediate boom 2
A support roller provided on the bottom plate b at the proximal end of the
It connects to the rod 22 and supports it. 26 is
This is a pin that fixes the base end of the rod 22 to the base end of the outer boom 1, and 27 is a fixture that is supported via the pin 26 and that fixes the tip of the piston rod 6. A stopper 28 is horizontally suspended between the left and right side plates c and c of the outer boom 1, and supports the fastening fitting 27 from the base end side of the boom. 30 is a pair of left and right pulleys arranged above the tip of the intermediate boom 2, 31 is a wire rope folding device arranged above the base end of the inner boom 3, and 32 is a pair of left and right pulleys arranged above the tip of the outer boom 1. The wire rope end fastening device 33 has one end fastened to the wire rope end fastening device 32 and is connected to the pulley 30, between the top plate a of the intermediate boom 2 and the top plate a of the inner boom 3,
A wire rope folding device 31, between the top plate a of the intermediate boom 2 and the top plate a of the inner boom 3, is a wire rope that passes through the pulley 30 in sequence and then fastens the other end to the other wire rope end fastening device 32. be. Therefore, when the intermediate boom 2 is extended by driving the telescopic hydraulic cylinder 4 to extend, the inner boom 3 is extended with respect to the intermediate boom 2 via the wire rope 33. 35 is a semicircular wire rope folding device installed horizontally at the tip of the rod 22, 36 is a pair of left and right wire rope end fasteners provided at the tip of the inner boom 3, and 37 is a wire rope folding device with one end attached to one wire. It is fixed to the rope end fastening device 36 and the inner boom 3 is fixed from there.
After successively passing through the inner upper left corner of the inner boom 3, one pulley 16, the wire rope folding device 35, the other pulley 16, and the inner upper right corner of the inner boom 3, the other end is fixed to the other wire rope end fixing device 36. It is a wire rope worn. Therefore, the telescopic hydraulic cylinder 4
When the intermediate boom 2 is retracted by driving the inner boom 3 to be retracted, the inner boom 3 is retracted relative to the intermediate boom 2 via the wire rope 37.

(Effects) The present invention constructed and operated as described above allows the outer end (bearing flange) of the pulley fitted onto the ear shaft to protrude beyond the extending end of the ear shaft. Since the telescopic hydraulic cylinder can be incorporated into the multi-stage telescopic boom, the amount of protrusion of the ear shaft can be reduced by the amount of the bearing flange compared to the conventional one, and the width of the telescopic boom can be reduced accordingly.

[Brief explanation of the drawing]

Fig. 1 is an explanatory diagram of a three-stage simultaneous telescopic boom showing one embodiment of the present invention, Fig. 2 is an enlarged sectional view showing the attached state of the pulley 16 in Fig. 1, and Fig. 3 is an It is an X sectional view. 4... Telescopic hydraulic cylinder, 5... Cylinder,
10...Ear shaft, 11...Blind hole, 3...Inner boom, 12...Boss fitting, 13...Pin hole, 14...
...Pin, 37...wire rope, 16...pulley.

Claims (1)

[Claims for Utility Model Registration] The outer boom 1 comprises an outer boom 1, an intermediate boom 2 telescopically inserted into the outer boom 1, and an inner boom 3 telescopically inserted into the intermediate boom 2. and the intermediate boom 2, the distal end of the piston rod 6 is connected to the base end of the outer boom 1, and the piston rod side end of the cylinder 5 is connected to the base end of the intermediate boom 2. An extension synchronization device and a contraction synchronization device are provided with a cylinder 4 and extend and retract the inner boom 3 relative to the intermediate boom 2 in synchronization with the telescoping motion of the intermediate boom 2 relative to the outer boom 1 by the telescoping hydraulic cylinder 4. In particular, on the left and right side walls of the base end of the intermediate boom 2, a pair of left and right boss fittings 1 are provided on these side walls.
2 and 12, and the telescopic hydraulic cylinder 4 includes:
A pair of left and right ear shafts 10, 1 having blind holes 11, 11 extending laterally of the cylinder and opening at the extending ends.
0 and a pair of left and right ear shafts 10, 10 in which the dimension between the extending ends of the ear shafts 10, 10 is slightly smaller than the inner dimension between the pair of left and right boss fittings 12, 12, Intermediate boom 2 at the piston rod side end of cylinder 5 of telescopic hydraulic cylinder 4
The pair of left and right ear shafts 10, 1 are connected to the base end portions.
0 is positioned between the left and right boss fittings 12, 12, and the pins 14, 14 are inserted between the corresponding boss fittings 12, 12 and the blind holes 11, 11 of the ear shaft, and the above-mentioned A pair of left and right ear shafts 10 are provided with a pulley 1 around which the wire rope 37 of the reduction tuning device is wound through bearings 17, 17, respectively.
In the arrangement structure of the pulley in the telescopic boom in which the bearings 6 and 16 are rotatably fitted, The ear shaft 1 is fitted onto the ear shafts 10, 10 via the bearings 17, 17
Bearing flanges 19, 19 for positioning the bearings of the pulleys 16, 16 externally fitted on the pulleys 16, 10,
The respective pulleys 16, 16 are connected to the bearing flanges 19, 19 via bearings 17, 17 so that the corresponding ear shafts 10 are located outside the extending ends of the corresponding ear shafts 10, 10. ，
In positioning the respective ear shafts 10, 10 of the telescopic hydraulic cylinder 4 in the state of being fitted externally into the respective boss fittings 12, 10, a part of the ear shafts 10, 10 of the extensible hydraulic cylinder 4, which is fitted externally to A structure for arranging a pulley in a telescopic boom, characterized in that cutouts 21, 21 are provided to allow the boom to move.