JPH0224388Y2 - - Google Patents

Description

[Detailed description of the invention] (Field of industrial application) This invention relates to an improvement in the structure of the track bushing and track link of the crawler track and the sprocket of the starting wheel for rotationally driving the track bushing and track link in a tracked traveling system. .

(Prior art) Conventionally, this type of starting wheel device is shown in Figs. 5 and 6.
It is configured as shown in the figure. That is, the outer circumference 11 of the starting wheel 1 has a protrusion 1 at its axial center.
9 is formed, and a protrusion 21 corresponding to the protrusion 19 is formed on the center side of the sprocket segment 20 having sprocket teeth 71. By overlapping these protrusions 19 and 21 and tightening with the bolt 9, the sprocket can be assembled. Segment 20 is the starting wheel 1
is installed against. A track bush 5 connecting the track link 4 of the crawler belt 3 is arranged to mesh with the sprocket teeth 71. In this structure, the track bushing 5 collides with the trough 72 of the sprocket teeth 71 at the starting end of the winding of the starting wheel during running, and the load from the track bushing 5 is transmitted to the starting wheel via the bolt 9. It turns out. The impact force generated at this time or the excavation reaction force during excavation work is applied to the track bush 5 and the valley part 72 of the sprocket tooth 71 which are meshed at the bottom.
There were problems in which the track bushing 5 was damaged and the bolts 9 attaching the sprocket segment 20 came loose.

(Purpose of the invention) This invention was made in order to eliminate such conventional drawbacks, and uses a simple structure to prevent impact force from being applied to the truck bushing, thereby preventing damage to the truck bushing. Moreover, the present invention provides a structure that prevents loosening of the bolts that attach the sprocket segment to the starting wheel.

(Structure of the invention) This invention is a tracked traveling device in which the track bushing of the crawler is meshed with and driven by the starting wheel so that the track travels. A sprocket is formed by attaching multiple sprocket segments, and each segment has sprocket teeth in the axial center of the starting wheel and flanges on both sides. The flange is connected to the driving wheel by bolts in a state in which the flange is in surface contact with the outer circumferential surface of the flange, and the track link of the crawler belt is in contact with the outer circumferential surface of the flange, so that the track bushing does not come into contact with the valley of the sprocket teeth. It is structured as follows.

In the above configuration, the load from the crawler track is transmitted to the sprocket segment via the track link, the track bush and the valley of the sprocket tooth do not come into contact with each other, and the load is transmitted as a compressive force to the mounting surface of the sprocket segment. Because of this, the factors that cause damage to the track bushing and loosening of the bolts are reduced, and the lifespan of these components is increased.

(Example) In FIGS. 1 and 2, a plurality of sprocket segments 2 are arranged in the circumferential direction on the outer circumferential portion 11 of the starting wheel 1 to constitute a sprocket. The track bushings 5 are engaged. In the case of the illustrated example, each sprocket segment 2 has four teeth 7 in the circumferential direction, and flanges 6 are formed at the base of the sprocket segment 2 on both sides in the axial direction of the starting wheel 1 (perpendicular to the paper plane of FIG. 1). , sprocket teeth 7 are formed in the center portion and protrude toward the outer circumference. Then, the outer circumferential surface of the starting wheel 1 (the outer circumferential surface of the outer circumferential portion 11) and the sprocket segment 2
The flange portion 6 is in surface contact with the inner circumferential surface of the flange portion 6.
A sprocket segment 2 is attached to the starting wheel 1 by bolts 12 and 13. The bolt heads of the bolts 12 and 13 are fitted into counterbore portions so that the heads do not protrude beyond the surface of the flange portion 6. Note that FIG. 1 partially shows a cross section of the bolt 13.

The inner circumferential surface of the track link 4 is in contact with the outer circumferential surface of the flange portion 6, and in this state, a gap t is always formed so that the track bush 5 does not come into contact with the troughs 72 of the sprocket teeth 7. There is.

FIG. 3 shows another embodiment of this invention, in which a hollow locking part 15 is formed inside the outer peripheral part 11 of the starting wheel 1, and the nut 14 of the tightening bolt 12 is fitted into this hollow part from the side. This allows the bolts 12, 13 to be tightened only from their head sides.

FIG. 4 shows still another embodiment, in which the outer circumferential surface of the outer circumferential portion 11 of the starting wheel 1 and the sprocket segment 2
A cushion material 8 such as highly compressible resin or rubber is sandwiched between the bolt 12 and the inner peripheral surface of the flange portion 6 of the bolt 12.
By this, the sprocket tooth 7
This is intended to reduce the impact force at the beginning of engagement between the track bushing 5 and the track bushing 5, and to prevent noise.

Furthermore, by forming serrations on the outer circumferential surface of the outer circumferential portion 11 and the inner circumferential surface of the flange portion 6, the force in the circumferential direction between the two is transmitted, thereby reducing the force applied to the bolt 12. You may also do so. Furthermore, in the structure shown in FIG. 3, the locking part 15 may be formed solid and tapped therein so that a bolt can be screwed in without using a nut.

In the above configuration, the load from the crawler track 3 is applied from the track link 4 to the flange portion 6 of the sprocket segment 2 at the contact point 10, and only the rotational transmission force acts on the track bush 5 between it and the sprocket tooth 7. Therefore, the impact force and excavation reaction force at the start of winding of the running driving wheel 1 do not act on the truck bushing 5, and therefore there is no risk of the truck bushing 5 being damaged by these factors, and the above-mentioned load is Sprocket segment 2
Acts as a compressive force between the inner circumferential surface of the starting wheel 1 and the outer circumferential surface of the starting wheel 1, and the shearing force due to the above load does not act on the coupling bolts 12 and 13, so the factors that cause the coupling bolts to loosen are greatly reduced. do.

(Effects of the invention) As explained above, this invention allows the load from the crawler track to be transmitted to the sprocket segment via the track link, so that the track bush and the troughs of the sprocket teeth do not come into contact with each other, and the sprocket Since the load acts as a compressive force on the mounting surface of the track segment, the causes of damage to the track bushing and bolt loosening are greatly reduced, and the life of the above components can be extended. .

[Brief explanation of the drawing]

Figure 1 shows an embodiment of this invention.
2 is a cross-sectional view of the starting wheel and sprocket segment showing the cross section of FIG. 1;
The figure is a partial sectional view showing another embodiment of the invention, FIG. 4 is a view corresponding to FIG. 3 showing yet another embodiment, and FIGS. 5 and 6 are respectively similar to FIGS. It is a figure equivalent figure. 1... Starting wheel, 2... Sprocket segment, 3... Track, 4... Track link, 5...
Track bushing, 6...Flange part, 7...Sprocket teeth, 12, 13...Tightening bolt, 7
2...Trough of sprocket tooth, t...Gap.

Claims (1)

[Scope of utility model registration request] In a tracked traveling device in which a track bushing of a crawler belt is meshed with and driven by a starting wheel to drive the track, a plurality of sprocket segments are attached to the outer periphery of the starting wheel in the circumferential direction. A sprocket is formed, and each segment has sprocket teeth in the axial center of the starting wheel.
Flanges are formed on both sides of the sprocket, and the flanges are connected to the starting wheel with bolts, with the outer circumferential surface of the starting wheel and the inner circumferential surface of the sprocket segment in surface contact. A tracked traveling device characterized in that the track link of the crawler belt comes into contact with the track bushing so that the track bush does not come into contact with the valley of the sprocket tooth.