JPH0655702U - Chain-saw chain drive sprocket - Google Patents

Abstract

(57) [Abstract] [Purpose] To extend the life of the drive teeth of the sprocket and the drive piece of the saw chain, suppress the weakening of the mounting parts of the drive teeth of the sprocket, and to improve the chip discharge function. The purpose is to improve. A drive tooth fitted into the drive tooth recess is entirely made of a cemented metal tip, and both side surfaces of the drive tooth recess formed on the outer peripheral surface side of the side ring are provided without being released. , The chip discharge notch is one in which both sides of the side ring are open.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a sprocket for driving a saw chain of a chain saw, which is used by being mounted on a spline shaft when transmitting the power of the chain saw to the saw chain.

[0002]

[Prior art]

 Known as the prior art of this kind by the inventor are the inventions and inventions described in Japanese Utility Model Publication No. 2-50303 and Japanese Patent Application Laid-Open No. 60-15101. The former device, as shown in FIG. 1 and FIG. 2 of the same publication, considers that side links (hereinafter, the terms “side link” and “side ring” are used separately in this specification). The tip for driving the drive piece of the saw chain provided in (1) is a super-hard material on the outer peripheral surface side of the side ring that constitutes the sprocket, while the support groove side for supporting the spline shaft tooth is provided. Although not always clear, it is presumed to be a special steel material such as SKS steel which is generally widely adopted, which is at least a non-superhard material.

Further, the drive tooth recess into which the tip is fitted is provided with a notch on the outer peripheral surface side of the side ring so as to face the support groove for supporting the spline shaft tooth provided on the peripheral surface of the circular through hole of the side ring. However, the side surface of the side ring is open.

Therefore, in this example, since the outer peripheral surface side of the side ring of the chip is made of a super-hard material, it is estimated that the wear is small at the time of use, but in reality, the total wear is still remarkable. But there are many problems.

The reason for this is that when the spline shaft rotates at high speed, the tip is violently contacted with the drive piece of the saw chain connected to the side link, so that the tip is impacted. Not only the tip side (super hard material part) but also the base end side (special steel material part) of the support groove side for supporting the spline shaft teeth cannot be avoided. Rather, it is clear that the base end portion of the drive tooth occupies the overwhelming majority of the portion that is subjected to the contact shock with the drive piece, because of the size of the diameter of the load portion.

[0006] Therefore, when the saw chain is used, the base end portion (special steel material portion) of the drive tooth described above is worn in a remarkably short period of time as compared with the tip end side (super hard material portion), and the life of the sprocket is reduced. However, it has a drawback that it can withstand only a few hours depending on the intended use. Further, structurally, the length of the super hard material in the axial direction is much shorter than the driving contact length of the driving piece, so that the partial wear of the driving piece back part of the saw chain is remarkable, and the saw chain There was also a problem that the service life of the computer would be shortened.

Further, the drive tooth recess formed on the outer peripheral surface side of the side ring has a notch on the side surface side of the side ring, and therefore the spline shaft tooth is provided on the opposite side of the drive tooth recess. Waiting for the formation of the supporting groove for supporting, the chip supporting part of the side ring has a state in which both sides are concavely cut, and as a result, it is extremely weakened and is often damaged. However, there was a problem that the sprocket could not be used in a short period of time.

In the latter invention, in order to discharge the chips generated when the saw chain is used, the chip discharge port is formed in the axial direction and the side surface from the outer peripheral surface of the side ring.

However, there is a problem that chips are not sufficiently discharged and clogging of chips is not small.

[0010]

[Problems to be solved by the device]

 The problems to be solved are that in the conventional technology, the wear of the base end portion of the drive tooth is severe, the drive piece of the saw chain is prematurely worn, and the tip support portion of the side ring is fragile for a short period of time. And the chip discharging function is insufficient.

[0011]

[Means for Solving the Problems]

 In this invention, a circular through hole for supporting a spline shaft is provided on the inside of an annular side ring, and the side surface of the circular through hole of the side ring faces the outer circumferential surface of the side ring at regular intervals. The support groove groups for supporting the spline shaft teeth are provided with the side parallel to the shaft center direction of the, and the support grooves for supporting the spline shaft teeth are hung from both sides of the support grooves for supporting the spline shaft teeth on the outer peripheral surface of the side ring. Two annular sprocket main bodies are provided, each of which has a groove for frustoconical pyramidal recess with a wide groove side and a narrow outer peripheral surface side of the side ring. A drive made of cemented carbide with a shape corresponding to the shape between the recesses for the drive teeth, which are formed by two sprocket-based recesses for the drive teeth, which face each other. There two sprockets principal while being bonded in contact with each other, Katsuso - chain - down of the drive piece is by coupling provided loose fit can gap devised and,

[0012] In the above-mentioned configuration, a consideration is provided in which notch for chip discharge portion, which is open on both sides on the outer periphery of the sprocket main body and is adjacent to the recess for drive teeth, is provided at regular intervals.

Further, the invention comprises a chip discharge guide surface provided by hanging from the inner end of the chip discharge portion notch to the shaft core side of the sprocket main body, and a device in which the driving teeth are made of ceramics. It is a thing.

[0014]

【Example】

 The details of this invention will be described with reference to the drawings. FIG. 1 is a side view showing a state where the sprocket 42 is mounted on the sprocket 40, and a part of the sprocket 42 on the sprocket 40 side is cut away.

2 is a perspective view of the sprocket main body 42, FIG. 3 is a perspective view of the drive teeth 22 made of cemented carbide, FIG. 4 is a side view of the sprocket main body 20 of the first embodiment, and FIG. 6 is a perspective view of the sprocket main body 20 of the embodiment, and FIG. 6 is a perspective view of the sprocket main body 20 of the third embodiment.

As is known, a circular through hole 12 for supporting the spline shaft is provided inside the annular side ring 10.

Although not shown in the drawing because it is known on the peripheral surface of the circular through hole 12 of the side ring 10, the outer periphery of the side ring 10 is inserted at regular intervals for inserting spline shaft teeth. And a group of support grooves 16 for supporting the spline shaft teeth, which are open to the side and open on the side parallel to the axial direction.

Needless to say, a spline shaft tooth group is inserted in the support groove 16 group in a direction perpendicular to the sprocket 42 to constitute means for transmitting the rotational movement of the spline shaft to the sprocket 42. .

The outer peripheral surface 14 of the side ring 10 is hung from both sides of the supporting groove 16 for supporting each spline shaft tooth, and the side of the supporting groove 16 for supporting the spline shaft tooth is wide, and the outer peripheral surface 14 side of the side ring 10 is narrow. Two annular sprocket main bodies 20 each having a truncated truncated cone-shaped drive tooth recess 18 are provided.

Then, the above-described truncated trapezoidal drive tooth recesses 18 of the two sprocket main bodies 20 face each other, and are constituted by the drive tooth recesses 18, 18 of the two sprocket main bodies 20. Between these drive tooth recesses 18, 18, drive teeth 22 made of cemented carbide and having a shape corresponding to the shape are connected.

As shown in FIG. 3, a concrete example of the drive teeth 22 made of cemented carbide is a truncated pyramid, and the material thereof is not only cemented carbide but also wear-resistant ones such as ceramics. adopt. Of course, it goes without saying that the entire drive tooth 22 is made of a hard metal, ceramics or the like, which has wear resistance.

When the two sprocket main bodies 20 are faced to each other and coupled, the drive piece 24 of the saw chain 40 can be loosely fitted between the two sprocket main bodies 20, 20. A gap D is provided between 20 and 20, and both are connected.

The provision of the constant gap D can be solved by adjusting the width of the drive teeth 22 described above.

That is, at least the width d of the drive tooth 22 on the outer peripheral surface 14 side of the side ring 10 is twice as thick as the thickness of the drive piece 24 of the saw chain 40 connected to the side link 41 and the drive tooth concave portion. The gap D can be provided by setting the depth of 18 to be equal to or slightly larger than the added dimension.

Of course, in order to allow the drive piece 24 of the saw chain 40 to be loosely fitted between the two sprocket main bodies 20, 20, the means for providing the gap D between the sprocket main bodies 20, 20 has been described above. Although not limited to the example, the illustration is omitted inside the side ring 10, but a gap may be provided by providing a protrusion parallel to the axis.

The means for connecting the drive teeth 22 to the drive tooth recesses 18, 18 and the means for connecting the two sprocket main bodies 20, 20 are preferably so-called brazing, but the inventor has proposed other connecting means. It is also planned to use a chemical adhesive. Further, the drive tooth concave portion 18 provided on the sprocket main body 20 makes the positioning of the respective parts easier and more accurate at the time of coupling with the drive tooth 22, and also increases the coupling area to greatly improve the coupling strength. is there.

In addition to the above-mentioned measures, the present invention will be described below because the chip discharge port is improved in order to improve the chip discharging function during use. FIG. 5 shows a second embodiment of the notch for discharging chips, and FIG. 5 is a perspective view of a single sprocket main body 20.

Semicircular chip discharge notches 26, which are open on both sides, are provided at regular intervals between the adjacent drive tooth recesses 18, 18 on the outer periphery of the sprocket main body 20. Needless to say, the shape of the chip discharging notch 26 is not limited to the semicircular shape.

Further, the example shown in FIG. 6 is an improvement of the second embodiment and is a chip discharge notch 28 according to the third embodiment, and the sprocket main part is provided from the inner end of the chip discharge notch 28. A taper-shaped chip discharge guide surface 30 is provided so as to be hung on the axial center side of the body 20 to gradually reduce the depth. The inventor also plans to provide the chip discharge guide surface 30 horizontally instead of limiting it to a tapered shape. Further, the inventor also experimentally tried to make the width of the chip discharge guide surface 30 the same or to widen the outer peripheral surface 14 side.

[0030]

[Effect of device]

 Since the present invention has the above configuration, it has the following advantages. (1) Since the entire drive teeth are made of cemented carbide or ceramics, the drive teeth do not wear much on the support groove side for supporting the spline shaft teeth, which is subject to severe impacts. Since the outer side surfaces of the side ring are not released, the supporting parts of the side ring that support the drive teeth are less fragile, increasing the sprocket's service life and driving the chain. The entire chain contacts the back of one side, so the life of the chain is extended. (2) Since the notches for discharging chips are notched on both sides of the side ring in the open state, the chips are less likely to be clogged during use. Further, since the chip discharge guide surface is provided so as to hang from the inner end of the chip discharge notch to the axial center side of the sprocket body, chips can be discharged more smoothly.

[Brief description of drawings]

FIG. 1 is a partially cutaway side view showing a state in which a sprocket is mounted on a saw chain.

FIG. 2 is a perspective view of a sprocket.

FIG. 3 is a perspective view of drive teeth made of cemented carbide.

FIG. 4 is a perspective view mainly of a sprocket.

FIG. 5 is a perspective view of a sprocket main body of another embodiment.

FIG. 6 is a perspective view of a sprocket main body of still another embodiment.

[Explanation of symbols]

10 Side Ring 12 Circular Through Hole for Supporting Spline Shaft 14 Outer Surface of Side Ring 16 Support Groove for Supporting Spline Shaft Teeth 18 Recess for Drive Teeth 20 Main Sprockets 22 Drive Teeth for Sprocket 24 Drive Piece for Saw Chain 26 Notch for chip discharge 28 Notch for chip discharge 30 Chip discharge guide 40 Saw chain 41 Side link 42 Sprocket D Gap between main sprocket d Width of drive tooth on outer peripheral side between two main sprocket

Claims (4)

[Scope of utility model registration request] 1. A circular through hole 12 for supporting a spline shaft is provided inside an annular side ring 10, and an outer peripheral surface 14 of the side ring 10 is provided at regular intervals on the peripheral surface of the circular through hole 12 of the side ring 10. And a group of support grooves 16 for supporting the spline shaft teeth, which are open on the side parallel to the axial direction of the side ring 10, are provided, and the outer peripheral surface of the side ring 10 is provided from both sides of the support grooves 16 for supporting the spline shaft teeth. 1
4 is wide on the side of the support groove 16 for supporting the spline shaft teeth, and narrowed on the outer peripheral surface 14 side of the side ring 10 to form the truncated trapezoidal drive tooth concave portion 18 for forming the annular sprocket main body 20. The drive tooth recesses 18, 18 of the two sprocket main bodies 20 are provided so as to face each other, and are formed by the drive tooth recesses 18, 18 of the two sprocket main bodies 20. A drive tooth 22 made of a hard metal having a shape corresponding to the shape is coupled between the tooth recesses 18, 18, two sprocket main bodies 20 are brought into contact with each other, and a drive piece of a saw chain 40 is provided. A sprocket for driving a saw chain of a chain saw, characterized in that a gap D for loosely fitting 24 is provided and coupled. 2. A circular through hole 12 for supporting a spline shaft is provided inside an annular side ring 10, and an outer peripheral surface 14 of the side ring 10 is provided at regular intervals on the peripheral surface of the circular through hole 12 of the side ring 10. And a group of support grooves 16 for supporting the spline shaft teeth, which are open on the side parallel to the axial direction of the side ring 10, are provided, and the outer peripheral surface of the side ring 10 is provided from both sides of the support grooves 16 for supporting the spline shaft teeth. 1
4 is wide on the side of the support groove 16 for supporting the spline shaft teeth, and narrowed on the outer peripheral surface 14 side of the side ring 10 to form the truncated trapezoidal drive tooth concave portion 18 for forming the annular sprocket main body 20. The drive tooth recesses 18, 18 of the two sprocket main bodies 20 are provided so as to face each other, and are formed by the drive tooth recesses 18, 18 of the two sprocket main bodies 20. A drive tooth 22 having a shape corresponding to the shape is coupled between the tooth recesses 18, 18, two sprocket main bodies 20 are brought into contact with each other, and a drive piece 24 of a saw chain 40 can be loosely fitted. A chain formed by connecting a gap D
A saw chain drive sprocket, characterized in that the drive teeth 22 are made of ceramics. 3. A circular through hole 12 for supporting a spline shaft is provided inside an annular side ring 10, and an outer peripheral surface 14 of the side ring 10 is provided at regular intervals on the peripheral surface of the circular through hole 12 of the side ring 10. And a group of support grooves 16 for supporting the spline shaft teeth, which are open on the side parallel to the axial direction of the side ring 10, are provided, and the outer peripheral surface of the side ring 10 is provided from both sides of the support grooves 16 for supporting the spline shaft teeth. 1
4 is wide on the side of the support groove 16 for supporting the spline shaft teeth, and narrowed on the outer peripheral surface 14 side of the side ring 10 to form the truncated trapezoidal drive tooth concave portion 18 for forming the annular sprocket main body 20. The drive tooth recesses 18, 18 of the two sprocket main bodies 20 are provided so as to face each other, and are formed by the drive tooth recesses 18, 18 of the two sprocket main bodies 20. A drive tooth 22 made of a hard metal having a shape corresponding to the shape is coupled between the tooth recesses 18, 18, two sprocket main bodies 20 are brought into contact with each other, and a drive piece of a saw chain 40 is provided. In a chain saw sprocket for driving a chain chain, in which a gap D is formed so that 24 can be loosely fitted, the drive tooth recesses 1 are provided on the outer periphery of the sprocket main body 20 and adjacent to each other. A chain saw sprocket for driving a saw chain of a chain saw, characterized in that cutouts 26 for the chip discharge portion, both side surfaces of which are open, are provided between 8 and 18 at regular intervals. 4. A circular through hole 12 for supporting a spline shaft is provided inside an annular side ring 10, and an outer circumferential surface 14 of the side ring 10 is provided at regular intervals on the circumferential surface of the circular through hole 12 of the side ring 10. And a group of support grooves 16 for supporting the spline shaft teeth, which are open on the side parallel to the axial direction of the side ring 10, are provided, and the outer peripheral surface of the side ring 10 is provided from both sides of the support grooves 16 for supporting the spline shaft teeth. 1
4 is wide on the side of the support groove 16 for supporting the spline shaft teeth, and narrowed on the outer peripheral surface 14 side of the side ring 10 to form the truncated trapezoidal drive tooth concave portion 18 for forming the annular sprocket main body 20. The drive tooth recesses 18, 18 of the two sprocket main bodies 20 are provided so as to face each other, and are formed by the drive tooth recesses 18, 18 of the two sprocket main bodies 20. A drive tooth 22 made of a hard metal having a shape corresponding to the shape is coupled between the tooth recesses 18, 18, two sprocket main bodies 20 are brought into contact with each other, and a drive piece of a saw chain 40 is provided. A chain saw chain drive sprocket in which a gap D allowing loose fitting of 24 is connected. In the sprocket main body 20, adjacent drive tooth recesses 18 are provided on the outer periphery of the sprocket main body 20. , 18 are provided on both sides of the chip discharge portion notches 28 at regular intervals, and the chips are discharged from the inner end of the chip discharge portion notches 28 to the axial core side of the sprocket main body 20. A sprocket for driving a saw chain of a chain saw, which is provided with a guide surface 30.