JP5515187B2 - Chainsaw guide plate - Google Patents

Description

  The present invention relates to a guide plate for a chain saw in which a sprocket is disposed at a tip portion and a saw chain is guided by a guide groove provided around the tip.

  Conventionally, a chain saw guide plate described in Patent Document 1 is known. The chain saw guide plate includes a sprocket (direction changing sprocket 15), an inner plate (covered discs 16 and 17) fixed by rivets between outer plates (side plates 14a and 14b), and an inner plate (covered disc). 16 and 17) are rotatably supported by bearings (rollers 18) arranged on the outer periphery. In this chain saw guide plate, the inner plate (covered discs 16, 17) is fixed to the outer plate (side plates 14a, 14b) of the guide plate by a plurality of rivets. No rotation occurred. However, in recent years, in order to reduce kickback and ensure safety, there is a tendency to reduce the number of sprocket teeth and to reduce the diameter of the semicircular plate-like portion at the front end of the guide plate. For this reason, as in the chain saw guide plate described in Patent Document 2, a sprocket (sprocket wheel 19) is fixed to the outer plate of the guide plate by one rivet (support shaft 18). . As such a guide plate, an inner plate fixed to the outer plate by one rivet is also conceivable.

JP-A-6-55503 JP 2007-62204 A

  However, in the case where the sprocket is fixed to the outer plate of the guide plate by one rivet like the above-mentioned chain saw guide plate, there is a possibility that the sprocket may be worn or damaged by long-term use. That is, when a chain saw using such a guide plate is driven by the power of an engine or the like, the sprocket is rotated at a high speed by the saw chain. Therefore, a slight vibration load is applied to the inner plate and the rivet through the bearing. And when cutting wood with a chainsaw, a larger load is applied to the inner plate and the rivet.

  Here, since the hardness of the rivet is lower than the hardness of the outer plate or the inner plate, the rivet may be worn when subjected to a large load over a long period of time. When the rivet is worn and the diameter is reduced, the rivet and the inner plate are not fixed to each other, and the inner plate rotates as the saw chain travels to shift the rotation axis of the sprocket. When the inner plate starts to rotate, the wear of the rivet further progresses and the rotating shaft of the inner plate further shifts, and the smooth rotation of the sprocket is hindered and the function of the chain saw is deteriorated. If the chain saw is continuously used in such a state, the sprocket may be damaged. In addition, when the rivet is worn, the rivet and the outer plate are not firmly fixed and the rivet rotates with respect to the outer plate.

  The present invention has been made in view of such conventional problems, and provides a chain saw guide plate capable of maintaining its function for a long period of time.

  In order to solve the above-described problem, the chain saw guide plate according to claim 1 is characterized in that, in the chain saw guide plate, the sprocket is disposed at the tip, and the saw chain is guided by a guide groove provided in the periphery. The guide plate includes a pair of outer plates and an inner plate sandwiched between the outer plates, and the sprocket includes an inner plate fixed between the outer plates by a rivet, and an outer periphery of the inner plate. It is rotatably supported by the arranged bearing, and a plurality of concave portions are provided in the peripheral portion of at least one rivet hole of both the outer plate and the inner plate.

  The guide plate of the chain saw according to claim 2 is characterized in that the maximum radial length of the recess is 2% to 20% of the radius of the rivet hole.

  A feature of the guide plate of the chainsaw according to claim 3 is that the concave portion is provided with a plurality of corner portions.

  The guide plate of the chain saw according to claim 4 is characterized in that a sprocket is arranged at the tip and the saw chain is guided by a guide groove provided around the guide plate. The guide plate includes a pair of outer plates. And an inner plate sandwiched between the outer plates, and the sprocket has a shaft that is rotatable by an inner plate fixed by a rivet between the outer plates and a bearing disposed on the outer periphery of the inner plate. At least one of the outer plates and the rivet holes of the inner plate is supported in an elliptical shape.

  The feature of the guide plate of the chain saw according to claim 5 is that the ratio of the major axis to the minor axis of the rivet hole is 1.02 to 1.20.

  In the chain saw guide plate according to the first aspect, at least one of the rivet holes of the outer plate and the inner plate is provided with a plurality of recesses in the peripheral portion. Therefore, when the rivet inserted into the rivet hole is crushed with a press, the rivet enters the recess. As a result, even if the rivet is somewhat worn due to long-term use of the chain saw, the inner plate is difficult to rotate due to the rivet that has entered the recess. That is, when a recess is provided in the rivet hole of the inner plate, the rivet that enters the recess makes it difficult for the rivet and the inner plate to be fixed, and the inner plate is difficult to rotate. In addition, if the rivet holes of both the outer plates are provided with recesses, the rivets that enter the recesses are difficult to remove from fixing the rivet and the outer plate. The inner plate is difficult to rotate. Furthermore, when the recessed part is provided in the rivet hole of an inner plate and both outer plates, both the above-mentioned effects are acquired. Therefore, according to the guide plate of this chain saw, the function can be maintained for a long time.

  In the chain saw guide plate according to the second aspect, since the maximum radial length of the recess is 2% to 20% of the radius of the rivet hole, the function can be maintained for a longer period. In addition, when the maximum radial length of the recess is less than 2% of the radius of the rivet hole, there are too few rivets entering the recess, and the above effect cannot be obtained sufficiently. Further, when the maximum radial length of the recess is larger than 20% of the radius of the rivet hole, a portion where the rivet is not filled may occur in the recess, and in this case also, the above effect cannot be sufficiently obtained.

  In the chain saw guide plate according to the third aspect, the recess is provided with a plurality of corners. Therefore, even if the rivet is somewhat worn, the inner plate is more difficult to rotate due to the rivet that has entered the corner. That is, when a plurality of corners are provided in the recesses of the rivet holes of the inner plate, the rivets that enter the corners make it difficult for the rivet and the inner plate to be fixed, and the inner plate is more difficult to rotate. Become. In addition, when a plurality of corners are provided in the recesses of the rivet holes of both the outer plates, the rivets that enter the corners are more difficult to be detached from the outer plates, so the rivets are not attached to the outer plates. As a result, the inner plate is more difficult to rotate. Furthermore, when a plurality of corners are provided in the recesses of the rivet holes of the inner plate and both outer plates, both of the above effects can be obtained. The “corner portion” in the present specification refers to a portion where the straight lines intersect, a portion where the curves intersect, and a portion where the straight line and the curve intersect, with respect to the straight lines and the curves constituting the outer shape of the recess. Moreover, the thing by which R shape and C shape are given to the corner | angular part is also contained.

  In the guide plate of the chain saw according to the fourth aspect, at least one rivet hole of both the outer plate and the inner plate has an elliptical shape. Therefore, when the rivet inserted into the rivet hole is crushed by a press, the cross section of the rivet changes from a perfect circle shape to an elliptical shape. As a result, even if the rivet is somewhat worn due to long-term use of the chainsaw, the inner plate is difficult to rotate. That is, when the rivet hole of the inner plate has an elliptical shape, the rivet between the rivet and the inner plate is formed by the rivet that has entered the portion outside the perfect circle having the radius of the short diameter in the major axis direction of the rivet hole of the inner plate. It becomes difficult to come off and the inner plate is difficult to rotate. Further, when the rivet holes of both the outer plates have an elliptical shape, the rivet and the outer plate are formed by a rivet that has entered a portion outside the perfect circle having the radius of the minor axis in the major axis direction of the rivet holes of both the outer plates. And the rivet is difficult to rotate with respect to the outer plate, and as a result, the inner plate is difficult to rotate. Further, when the rivet holes of the inner plate and both outer plates are elliptical, both of the above effects can be obtained. Therefore, according to the guide plate of this chain saw, the function can be maintained for a long time.

  In the chain saw guide plate according to the fifth aspect, since the value of the ratio of the major axis to the minor axis of the rivet hole is 1.02 to 1.20, the function can be maintained for a longer period. In addition, when the value of the ratio of the major axis to the minor axis of the rivet hole is less than 1.02, there are too few rivets entering the portion outside the perfect circle having the minor axis radius in the major axis direction of the rivet hole. The above effects cannot be obtained sufficiently. In addition, when the ratio of the major axis to the minor axis of the rivet hole is greater than 1.20, there is a portion where the rivet is not filled in a part outside the perfect circle having the minor axis radius in the major axis direction of the rivet hole. In this case as well, the above effect cannot be obtained sufficiently.

The exploded perspective view of the guide board of the chainsaw of Embodiment 1-3. The assembly enlarged view of the guide board of the chainsaw of Embodiment 1-3. The enlarged view of the rivet hole of a guide plate, and a rivet concerning the guide plate of the chainsaw of Embodiment 1. FIG. The enlarged view of the rivet hole of an inner plate, and a rivet in connection with the guide plate of the chainsaw of Embodiment 1. FIG. The enlarged view of the rivet hole of a guide plate and a rivet concerning the guide plate of the chainsaw of Embodiment 2. FIG. The enlarged view of the rivet hole of an inner plate, and a rivet in connection with the guide plate of the chainsaw of Embodiment 2. FIG. FIG. 4 is an enlarged view of a rivet hole and a rivet of a guide plate according to the guide plate of the chain saw of the third embodiment. The enlarged view of the rivet hole of an inner plate, and a rivet in connection with the guide plate of the chainsaw of Embodiment 3. FIG.

  Embodiments 1 to 3 embodying a chain saw guide plate according to the present invention will be described below with reference to the drawings. First, the guide plate of the chain saw of Embodiment 1 is demonstrated. FIG. 1 is an exploded perspective view of a chain saw guide plate. FIG. 2 is an enlarged view of the tip of the chain saw guide plate assembly drawing. However, in FIG. 2, the description of the front outer plate 1 is omitted. As shown in FIGS. 1 and 2, the chain saw guide plate includes a pair of outer plates 1 and an inner plate 2 sandwiched between both outer plates 1.

  The outer plate 1 is a steel plate having a substantially oval shape, and has a rivet hole 11 at the tip. Similarly, the inner plate 2 is a steel plate having a substantially oval shape, and its outer shape is slightly smaller than that of the outer plate 1. The outer plate 1 and the inner plate 2 are joined and integrated. A guide groove 1a is formed by the difference in outer shape between the outer plate 1 and the inner plate 2, and a saw chain (not shown) is guided by the guide groove 1a. Further, the front end portion of the inner plate 2 is lacking in an arc shape, and the inner plate 3, the bearing 4, and the sprocket 5 are interposed in a gap 2 a formed by joining both the outer plates 1 and the inner plate 2.

  The inner plate 3 has a disc shape and has a rivet hole 21 in the center. The inner plate 3 is fixed between the two outer plates 1 by rivets 6. A bearing 4 is attached to the inner plate 3, and a sprocket 5 is attached to the bearing 4. Thus, the sprocket 5 is rotatably supported by the inner plate 3. The sprocket 5 has a disk shape, and teeth 5a on which a saw chain is hung are formed on the outer periphery.

  FIG. 3 is an enlarged view of the rivet hole 11 and the rivet 6 opened at the tip of the outer plate 1. As shown in FIG. 3, two concave portions 11 a having an arcuate outer shape are provided in the peripheral portion of the rivet hole 11 having the radius r <b> 1. The maximum length L1 in the radial direction of the recess 11a is preferably 2% to 20% of the radius r1 of the rivet hole 11. And the rivet 6 crushed by the press is press-fitted into the rivet hole 11 without a gap. A normal rivet hole is indicated by a dotted line.

  FIG. 4 is an enlarged view of the rivet hole 21 and the rivet 6 of the inner plate 3. As shown in FIG. 4, two concave portions 21 a having an arcuate outer shape are provided in the peripheral portion of the rivet hole 21 having the radius r <b> 1. The maximum radial length L1 of the recess 21a is preferably 2% to 20% of the radius r1 of the rivet hole 21. The rivet 6 crushed by the press is press-fitted into the rivet hole 21 without a gap. A normal rivet hole is indicated by a dotted line.

  In the guide plate of the chain saw of the first embodiment, two concave portions 11a and 21a are provided in the peripheral portions of the rivet holes 11 and 21 of both the outer plates 1 and the inner plate 3, respectively. Therefore, when the rivet 6 inserted into the rivet holes 11 and 21 is crushed with a press, the rivet 6 enters the recesses 11a and 21a. As a result, even if the rivet 6 is somewhat worn due to long-term use of the chain saw, the inner plate 3 is difficult to rotate due to the rivet 6 that has entered the recesses 11a and 21a. That is, the rivet 6 that has entered the recess 21a of the rivet hole 21 of the inner plate 3 makes it difficult for the rivet 6 and the inner plate 3 to be fixed, and the inner plate 3 is difficult to rotate. Further, the rivets 6 that have entered the recesses 11a of the rivet holes 11 of the both outer plates 1 are difficult to be detached from the rivet 6 and the outer plate 1, so that the rivet 6 is difficult to rotate with respect to the outer plate 1, and as a result The plate 3 becomes difficult to rotate. Therefore, according to the guide plate of this chain saw, the function can be maintained for a long time. Furthermore, if the maximum length L1 in the radial direction of the recesses 11a and 21a is 2% to 20% of the radius r1 of the rivet holes 11 and 21, the function of the chain saw guide plate can be maintained for a longer period of time. Can do.

  In the present embodiment, the recesses 11a and 21a are provided in the peripheral portions of the rivet holes 11 and 21 of the outer plates 1 and the inner plate 3, respectively. You may provide the recessed parts 11a and 21a only in the peripheral part of the holes 11 and 21. FIG. Furthermore, although the two recessed parts 11a and 21a were provided in the peripheral part of the rivet holes 11 and 21, respectively, you may provide three or more recessed parts 11a and 21a.

  The overall configuration of the chain saw guide plate of the second embodiment is the same as that shown in FIGS. 1 and 2 as in the first embodiment, and the description thereof is omitted. FIG. 5 is an enlarged view of the rivet hole 12 and the rivet 6 opened at the tip of the outer plate 1. As shown in FIG. 5, four concave portions 12a having a maximum radial length L1 are provided in the peripheral portion of the rivet hole 12 having a radius r1. The recess 12a has an arcuate base 12b and two linear sides 12c. And the part which the base 12b and the side 12c cross | intersect is the corner | angular part 12d. The maximum length L1 is preferably 2% to 20% of the radius r1 of the rivet hole 12. And the rivet 6 crushed by the press is press-fitted without gaps to the corner 12d. A normal rivet hole is indicated by a dotted line.

  FIG. 6 is an enlarged view of the rivet hole 22 and the rivet 6 of the inner plate 3. As shown in FIG. 6, four recesses 22a having a maximum radial length L1 are provided on the periphery of the rivet hole 22 having a radius r1. The concave portion 22a has a bottom side 22b having an arc shape and two side sides 22c having a linear shape. And the part which the base 22b and the side 22c cross | intersect is the corner | angular part 22d. The maximum length L1 is preferably 2% to 20% of the radius r1 of the rivet hole 22. And the rivet 6 crushed by the press is press-fitted without any gap to the corner 22d. A normal rivet hole is indicated by a dotted line.

In the guide plate of the chain saw of the second embodiment, four recesses 12a and 22a are provided in the peripheral portions of the rivet holes 12 and 22 of both the outer plates 1 and the inner plate 3, respectively.
Moreover, it is preferable that the maximum length L1 in the radial direction of the recesses 12a and 22a is 2% to 20% of the radius r1 of the rivet holes 12 and 22. Furthermore, corners 12d and 22d are formed in the recesses 12a and 22a. Therefore, when the rivet 6 inserted into the rivet holes 12 and 22 is crushed with a press, the rivet 6 enters the corners 12d and 22d. As a result, even if the rivet 6 is somewhat worn due to long-term use of the chain saw, the inner plate 3 is more difficult to rotate due to the rivet 6 that has entered the corners 12d and 22d. That is, the rivet 6 that has entered the corner portion 22d provided in the recess 22a of the rivet hole 22 of the inner plate 3 makes it difficult for the rivet 6 and the inner plate 3 to be firmly fixed, and the inner plate 3 becomes more difficult to rotate. . In addition, the rivet 6 and the outer plate 1 are more difficult to be separated by the rivet 6 that has entered the corner portion 12d provided in the concave portion 12a of the rivet hole 12 of both the outer plates 1. As a result, the inner plate 3 becomes more difficult to rotate. Therefore, according to the guide plate of this chain saw, the function can be maintained for a long time. Other effects are the same as those of the first embodiment.

  Also in the present embodiment, as in the first embodiment, the concave portions 12 a and 22 a may be provided only in the peripheral portions of the rivet holes 12 and 22 of either the outer plate 1 or the inner plate 3. Furthermore, although the four recessed portions 12a and 2a are provided in the peripheral portions of the rivet holes 12 and 22, respectively, the number is not limited to this number, and for example, two recessed portions 12a and 22a may be provided.

  The overall configuration of the chain saw guide plate of the third embodiment is the same as that shown in FIGS. 1 and 2 as in the first embodiment, and the description thereof is omitted. FIG. 7 is an enlarged view of the rivet hole 13 and the rivet 6 opened at the tip of the outer plate 1. As shown in FIG. 7, the rivet hole 13 has an elliptical shape with a minor axis r1 and a major axis r2. The ratio of the major axis r2 to the minor axis r1 is preferably 1.02-1.20. The rivet 6 crushed by the press is press-fitted into the rivet hole 13 without a gap. A normal rivet hole is indicated by a dotted line. The minor axis r1 is the same as the radius r1 of a normal rivet hole.

  FIG. 8 is an enlarged view of the rivet hole 23 and the rivet 6 of the inner plate 3. As shown in FIG. 8, the rivet hole 23 has an elliptical shape with a short diameter r1 and a long diameter r2. The ratio of the major axis r2 to the minor axis r1 is preferably 1.02-1.20. The rivet 6 crushed by the press is press-fitted into the rivet hole 23 without a gap. A normal rivet hole is indicated by a dotted line.

  In the chain saw guide plate of the third embodiment, the rivet holes 13 and 23 of both the outer plate 1 and the inner plate 3 have an elliptical shape with a short diameter r1 and a long diameter r2. When the rivet 6 inserted into the rivet holes 13 and 23 is crushed with a press, the rivet 6 enters the corners of the rivet holes 13 and 23. Thereby, even if the rivet 6 is somewhat worn away due to long-term use of the chainsaw, the inner plate 3 is difficult to rotate. That is, in the direction of the major axis r2 of the rivet hole 23 of the inner plate 3, the rivet 6 that has entered the portion outside the perfect circle of the minor axis r1 makes it difficult for the rivet 6 and the inner plate 3 to be firmly fixed. It becomes difficult to rotate. Further, the rivet 6 and the outer plate 1 are not easily fixed by the rivet 6 that has entered the portion outside the true circle of the short diameter r1 in the major axis r2 direction of the rivet holes 13 of both outer plates 1. Becomes difficult to rotate with respect to the outer plate 1, and as a result, the inner plate 3 becomes difficult to rotate. Therefore, according to the guide plate of this chain saw, the function can be maintained for a long time. Furthermore, if the value of the ratio of the major axis r2 to the minor axis r1 is 1.02-1.20, the function of the chain saw guide plate can be maintained for a longer period. In the present embodiment, the rivet holes 13 and 23 of both the outer plates 1 and the inner plate 3 are elliptical, but only the rivet holes 13 and 23 of either the outer plate 1 or the inner plate 3 are used. It may be oval.

  As mentioned above, although the guide plate of the chain saw of this invention was demonstrated according to Embodiment 1-3, this invention is not restrict | limited to these, As long as it is not contrary to the technical idea of this invention, it changes suitably. Needless to say, this is applicable.

  DESCRIPTION OF SYMBOLS 1 ... Outer plate, 1a ... Guide groove, 2 ... Inner plate, 3 ... Inner plate, 4 ... Bearing, 5 ... Sprocket, 6 ... Rivet, 11, 12, 13, 21, 22, 23 ... Rivet hole, 11a, 12a , 21a, 22a ... recess, 12d, 22d ... corner, L1 ... maximum length, r1 ... radius (minor axis), r2 ... major axis.

Claims (5)

In a chain saw guide plate in which a sprocket is arranged at the tip, and a saw chain is guided by a guide groove provided in the periphery,
The guide plate includes a pair of outer plates and an inner plate sandwiched between the outer plates,
The sprocket is rotatably supported by an inner plate fixed by a rivet between the outer plates and a bearing disposed on the outer periphery of the inner plate,
A guide plate for a chain saw, wherein at least one rivet hole of each of the outer plates and the inner plate is provided with a plurality of recesses in the peripheral portion.   2. The chain saw guide plate according to claim 1, wherein a maximum length of the concave portion in a radial direction is 2% to 20% of a radius of the rivet hole.   3. The chain saw guide plate according to claim 1, wherein the recess is provided with a plurality of corners. In a chain saw guide plate in which a sprocket is arranged at the tip, and a saw chain is guided by a guide groove provided in the periphery,
The guide plate includes a pair of outer plates and an inner plate sandwiched between the outer plates,
The sprocket is rotatably supported by an inner plate fixed by a rivet between the outer plates and a bearing disposed on the outer periphery of the inner plate,
A guide plate for a chain saw, wherein at least one rivet hole of each of the outer plates and the inner plate has an elliptical shape.   5. The chain saw guide plate according to claim 4, wherein a ratio of a major axis to a minor axis of the rivet hole is 1.02 to 1.20.

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