WO2018003368A1

WO2018003368A1 - Chain saw

Info

Publication number: WO2018003368A1
Application number: PCT/JP2017/019710
Authority: WO
Inventors: 翔平佐々木
Original assignee: 日立工機株式会社
Priority date: 2016-06-27
Filing date: 2017-05-26
Publication date: 2018-01-04
Also published as: JP6648829B2; JPWO2018003368A1

Abstract

Provided is a chain saw configured so that nuts for affixing a side cover and a guide bar will not become dislodged from the body housing side. A chain saw 1 provided with a side cover 40, wherein retention rings for retaining nuts 33, 34 so that the nuts 33, 34 will not become dislodged in the axial direction of bolts 31, 32 are provided near ends of the shafts of the bolts 31, 32 extending perpendicularly to a side surface of a body housing 3. The side cover 40 is provided with through-holes 42, 43 through which the nuts 33, 34 can pass. The through-holes 42, 43 are composed of round holes formed on the front side and larger than the nuts 33, 34, and of oval cutouts extending rearwards from the round holes. The nuts 33, 34 are fastened at the cutout sections. The side cover 40 is removed by loosening the nuts 33, 34 and moving the side cover 40 rearwards and then sidewards.

Description

Chain saw

The present invention relates to a chain saw that cuts wood or the like by rotationally driving an endless chain saw using a motor or an engine as a drive source, and more particularly to an improvement in a side cover mounting structure for fixing a guide bar.

The chain saw uses an engine or an electric motor as a driving source to drive a loop-shaped saw chain having a sharp blade on the outer teeth. The saw chain is spanned between the guide bar and the sprocket, and the rotational driving force of the drive source is transmitted through the sprocket to rotate along the outer peripheral edge of the guide bar. In addition, a tension adjusting mechanism for adjusting the tension of the saw chain spanned between the guide bar and the sprocket is provided. For example, Patent Document 1 is known as such a chain saw.

Here, the mounting structure of the side cover of the conventional chain saw will be described with reference to FIGS. FIG. 9 is a right side view showing the external shape of a conventional chain saw 201. The chain saw 201 is driven by the engine 10 housed in the main body housing 203, and is fixed so that the guide bar 12 protrudes forward from the right side surface of the main body housing 203. A saw chain (not shown) having a loop shape in which a plurality of sharp blades protrude outward at a predetermined interval is wound around the periphery of the guide bar 12, and cutting a tree or a branch by rotating the saw chain at a high speed Is possible. The main body housing 203 is manufactured by integral molding of synthetic resin such as plastic, and the upper side is covered with the top cover 6. A rear handle 4 is provided behind the main body housing 203 for the operator to hold. A front handle 5 is provided on the upper side of the main body housing 203 for the operator to hold.

For example, the worker holds the rear handle 4 with the right hand and holds the front handle 5 with the left hand to perform the work. A trigger lever 8 for adjusting the throttle of the engine 10 is provided below the rear handle 4, and the operator can operate the trigger lever 8 by grasping the lock lever 9. A spike 13 is provided on the front side of the main body housing 3 for guiding when cutting a log or the like. A brake lever 7 is disposed on the front side of the left and right portions of the front handle 5 with a predetermined distance therebetween. The brake lever 7 serves as a hand guard that protects the operator's hand from being exposed to branches or cuts, and also serves as an operation lever for a brake mechanism (not shown) that immediately stops the rotation of the saw chain. .

A side cover 240 is provided on the right side of the main body housing 203 so as to cover a drive mechanism (described later) that rotates the saw chain. The side cover 240 is fixed to the two

bolts

231 and 232 extending to the right side from the main body housing 203 using

nuts

33 and 34. The side cover 240 is formed with two bolt holes (not visible in the figure) for allowing the

bolts

231 and 232 to pass therethrough.

Next, a procedure for removing the side cover 240 in the conventional chain saw 201 will be described with reference to FIG. 10 (1) to 10 (3) are cross-sectional views taken along the line DD in FIG. The crankshaft 11 of the engine 10 extends from the opening of the main body housing 203, and a known centrifugal clutch mechanism 20 is provided there. A sprocket 24 is provided outside the clutch drum 23 of the centrifugal clutch mechanism 20, and a guide bar 12 is attached to the front side of the sprocket 24. The guide bar 12 is positioned so as to be in contact with the attachment surface 203b of the main body housing 203, and is sandwiched between the holding surface 241a of the side cover 240. Two

bolts

231 and 232 are fixed to the right side from the main body housing 203, and the side cover 240 and the guide bar 12 are fastened together by tightening the

nuts

233 and 234 from the tips of the

bolts

231 and 232. The head sides of the

bolts

231 and 232 are cast on the synthetic resin main body housing 203 side or fixed by a known fixing method.

FIG. 10 (2) is a view showing a state in which the

nuts

233 and 234 are completely removed from the state of (1). By completely removing the

nuts

233 and 234 from the

bolts

231 and 232 in this way, the side cover 240 becomes removable, and the side cover 240 is removed by moving it in the direction of the arrow 250 in FIG. Can do. A recessed portion 241 is formed in a portion of the side cover 240 where the

nuts

233 and 234 are fixed, and

bolt holes

242 and 243 for penetrating the

bolts

231 and 232 are formed therein. Note that the guide bar 12 can also be detached from the main body housing 203 by moving the guide bar 12 in the direction of the arrow 250 from the state of FIG.

JP 2009-279883 A

In a chain saw, it is important to adjust the tension of the saw chain when the saw chain is replaced or when the circumference of the saw chain is extended due to wear of the connecting pins. When replacing the saw chain, it is necessary to remove the side cover from the main body housing. To adjust the tension of the saw chain, it is necessary to loosen the fastening of the bolts and nuts that secure the side cover to the housing. The direction in which the guide bar approaches or separates from the sprocket by the tension adjustment mechanism with the nuts loosened Move to. In the conventional chain saw, when the

fixing nuts

33 and 34 are loosened, they can be easily removed from the bolt side (not shown). In addition, when the

nuts

33 and 34 are loosened to adjust the tension of the saw chain, the

nuts

33 and 34 may be detached due to excessive loosening, and the

nuts

33 and 34 may be lost.

The present invention has been made in view of the above background, and an object thereof is to provide a chain saw in which a nut for fixing a side cover and a guide bar is prevented from falling off from the main body housing side. Another object of the present invention is to provide a chain saw having a side cover fixed with bolts and nuts, in which the side cover can be removed without completely removing the nuts from the bolts.

The characteristics of representative ones of the inventions disclosed in the present application will be described as follows. According to one aspect of the present invention, a saw chain, a guide bar attached to the main body housing and over which the saw chain is spanned, a drive source that drives the saw chain, a sprocket that transmits rotational force from the drive source to the saw chain, and a guide A chain saw that includes a part of the bar and a side cover for covering the sprocket and fixing the guide bar to the main body housing, the main body housing is provided with fixing means for fixing the side cover with screws, A through hole through which the fixing means can pass is formed. In addition, a locking hole is formed to be connected to the through hole and engage with the fixing means. The fixing means is passed through the through hole, and the side cover is moved in the surface direction of the guide bar to fix the fixing means. It was comprised so that it might fix in the position of a locking hole.

According to another feature of the present invention, the fixing means is a bolt extending perpendicular to the side surface of the main body housing and a nut attached to the bolt, and the locking hole is directed from the through hole toward one of the radial directions. It is an oval cutout that extends and has a minor axis smaller than the two-surface width of the nut, and fixing by the fixing means is performed by tightening the nut to the bolt and sandwiching the outer periphery of the locking hole. The bolt has an attachment shaft extending from the main body housing through the attachment hole of the guide bar and through the locking hole of the side cover, and after the nut is attached to the attachment shaft, the nut comes off from the attachment shaft. A restricting means is provided so that the side cover can be removed from the main body housing while the nut is engaged with the bolt. Furthermore, a male screw is formed on the outer periphery of the bolt mounting shaft, a continuous groove (part having a small diameter) is formed in the vicinity of the tip, and the restricting means is fitted in the continuous groove. It consists of a retaining ring.

According to still another feature of the present invention, the locking hole is disposed so that the longitudinal direction is parallel to the longitudinal direction of the guide bar, and the mounting shaft is moved from the inside of the through hole to the inside of the locking hole. Thus, the side cover can be moved in the longitudinal direction of the guide bar. Further, the side cover is provided with tension adjusting means for adjusting the tension of the saw chain by moving the guide bar in the front-rear direction with respect to the main body housing, and by disposing the locking hole on the rear side of the through hole. The tension on the saw chain is loosened when the side cover is removed.

According to still another feature of the present invention, the concave portion or the convex portion is provided in the main body housing and the side cover, and the concave portion and the convex portion are fitted when the side cover is fixed, thereby suppressing the relative movement in the front-rear direction. It was to so. Further, a brake for suppressing the rotation of the sprocket and a tension adjusting means for adjusting the tension of the saw chain are provided on the main body housing side, and the locking hole is arranged to extend forward from the through hole.

According to the present invention, it is possible to easily attach and remove the side cover, and it is possible to provide a highly convenient chain saw because there is no risk of the nut falling from the bolt when the side cover is removed. In addition, since the nut is configured not to be detached from the bolt, the risk of licking the corner of the nut or damaging the thread of the bolt when attaching the side cover or adjusting the tension of the saw chain can be significantly reduced. Product life can be greatly improved. The above and other objects and novel features of the present invention will become apparent from the following description and drawings.

It is a right view of the chain saw which concerns on the Example of this invention (state which attached the side cover). It is the elements on larger scale of the hollow part 41 of the side cover 40 of FIG. It is a side view which shows the state in the middle of removing the side cover from the state of FIG. FIG. 2 is a view for illustrating a procedure for removing a side cover from the state of FIG. 1, wherein (1) to (4) are cross-sectional views taken along a line AA in FIG. It is a side view (partial perspective view) which shows the structure of the chain saw which concerns on 2nd Example of this invention. FIG. 6 is a cross-sectional view taken along a line BB in FIG. It is a figure which shows the state at the time of moving and fixing the side cover 140 of the chain saw which concerns on 2nd Example of this invention to the back side, (1) is a side view, (2) is C- It is a fragmentary sectional view of the C section. FIGS. 8A and 8B are views showing a state in which the side cover 140 is moved to the front side in order to remove the side cover 140 from the state of FIG. 7, wherein FIG. 7A is a side view and FIG. It is a right view of the conventional chain saw. FIG. 10 is a view for explaining a procedure for removing a side cover in a conventional chain saw, wherein (1) to (3) are cross-sectional views taken along a line DD in FIG. 9;

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In addition, the same code | symbol is attached | subjected to the same member and repeated description is abbreviate | omitted. Further, in this specification, description will be made assuming that the front, rear, left, right, and up and down directions are directions shown in the drawing. FIG. 1 is a right side view of a chain saw 1 according to an embodiment. The configuration of the chain saw other than the shape of the side cover 40, the change in the shape of the main body housing 3 for attaching the side cover 40 (fixing hole 3b), and the fixing means for the side cover using bolts and nuts, This is the same as the conventional chain saw 201 shown in FIG.

The side cover 40 is fixed to two

bolts

31 and 32 as two attachment shafts extending from the main body housing 3 by two

nuts

33 and 34. However, in the present embodiment, it is configured so that the two

nuts

33 and 34 as the second fixing member cannot be removed from the

bolts

31 and 32 as the first fixing member by using a retaining ring described later in FIG. Furthermore, the shape of the

hole parts

42 and 43 which penetrate the volt |

bolts

31 and 32 of the side cover 40 so that the side cover 40 can be removed from the main body housing 3 with the two

nuts

33 and 34 attached to the

bolts

31 and 32. Changed.

FIG. 2 is a partially enlarged view showing the shapes of the

holes

42 and 43 of the side cover 40. The

holes

42 and 43 are formed by large circular through

holes

42a and 43a and elongated locking

holes

42b and 43b extending to the rear side thereof. Through holes 42a, the diameter _{R 1} of 43a is set to a larger circular degree with a predetermined gap than the maximum outer edge position of the nut 33, 34 (diagonal distances), the nut 33 and the through

holes

42a, 43a Enabled to penetrate. On the other hand, the locking

holes

42b and 43b have a width W1 corresponding to the diameters of the bolt holes 242 and 243 in the conventional chain saw 201. That is, the locking

holes

42b and 43b extend from the through

holes

42a and 43a toward the rear in one radial direction, and have an oval cutout whose short diameter (width W1) is smaller than the two-surface width of the nuts 33 and 34. did. The width W1 is slightly larger than the shaft diameter of the

bolts

31 and 32, and is formed to be sufficiently smaller than the minimum outer edge position (two-surface width) of the nuts 33 and 34. When the side covers 40 are fixed by tightening the

bolts

31 and 32, for example, the positions of the

bolts

31 and 32 are set to the positions of the dotted lines 31a so as to contact the rear end sides of the locking holes 42b and 43b. By forming the

holes

42 and 43 having such characteristic shapes as described above, the nuts 33 and 34 are still attached to the

bolts

31 and 32 and the side cover 40 is attached to the main body housing 3 in the loosened state. Can be attached or removed. Returning again to FIG.

A tension adjusting mechanism 45 for adjusting the tension of the saw chain (not shown) by adjusting the position of the guide bar 12 in the front-rear direction is provided inside the side cover 40. The tension adjusting mechanism 45 is a known mechanism that is also used in conventional chain saws, and a method of providing the tension adjusting mechanism 45 on the side cover 40 side and a method of providing the tension adjusting mechanism 45 on the main body housing 3 side are known. In this embodiment, the tension adjusting mechanism 45 is provided on the side cover 40 side. The tension adjusting mechanism 45 includes a long screw 46 that is rotatably fixed to the side cover 40, a nut portion 47 that is fixed so that relative rotation with the side cover 40 is impossible at the end of the long screw 46, and a screw to the long screw 46. The chain pulling boss 48 extends in a direction perpendicular to the longitudinal direction of the long screw 46 and perpendicular to the surface of the guide bar 12. The chain pulling boss 48 is formed with a female thread portion through which the long screw 46 passes, and the head of the long screw 46 is configured to be accessible from the outside of the side cover 40. By changing the axial position (front-rear direction position) of the screw 46, the front-rear direction position of the guide bar 12 can be adjusted. Although not shown here, the guide bar 12 is formed with a through hole for allowing the chain pulling boss 48 to pass therethrough.

FIG. 3 is a side view showing a state when the side cover 40 is removed from the state of FIG. When the nuts 33 and 34 are loosened in the state of FIG. 1, the side cover 40 can be moved rearward as indicated by an arrow 52. When the side cover 40 is moved to the rear side, the chain pulling boss 48 is also moved with respect to the main body housing 3, so that the guide bar 12 is also moved to the rear side accordingly. Since the movement of the guide bar 12 to the rear side is a movement in the direction of loosening the tension of the saw chain, this movement is easy. Therefore, the side cover 40 can be easily moved rearward without changing the adjustment state of the tension adjusting mechanism 45. When the side cover 40 is moved rearward as shown in FIG. 3, the rear end surface 40 b of the side cover 40 comes into contact with the front handle 5. At this time, if the center positions of the nuts 33 and 34 are positioned at the center of the through

holes

42a and 43a of the

hole portions

42 and 43, the side cover 40 is moved to the right from that state (the state of FIG. 3). Thus, the side cover 40 can be removed from the main body housing 3.

FIG. 4 is a partial bottom view for illustrating a procedure for removing the side cover from the state of FIG. (1) is a state in which the nuts 33 and 34 are tightened at the

elongated holes

42b and 43b, and the guide bar 12 is fixed, that is, a state in which work is performed with a chain saw. A chain pulling boss 48 provided on the side cover 40 side is fitted in a fitting hole 12 b formed in the guide bar 12. On the rear side of the side cover 40, a convex protrusion 44 extending from the side cover 40 is positioned inside a concave fixing hole 3 b formed in the main body housing 3. When the convex portions are fitted, relative movement in the front-rear direction is suppressed. For this reason, even if an impact is applied to the side cover 40 during work, the side cover 40 does not move. Here, the convex portion is formed on the side cover 40 side, and the concave portion is formed on the main body housing 3 side. However, these are reversed to form the convex portion on the main body housing 3 side and the concave portion on the side cover 40 side. You may comprise so that it may form. Moreover, it is not restricted only to an uneven | corrugated | grooved part, Other structures may be sufficient if it is a stopper member which prevents the movement so that the side cover 40 may not slide, when the nuts 33 and 34 are tightened.

In FIG. 4B, when the nuts 33 and 34 are loosened, the nuts 33 and 34 move in the axial direction (right direction) along the threads of the

bolts

31 and 32. In this embodiment,

continuous grooves

37 and 38 that are continuous in the circumferential direction are cut at the ends of the nuts 33 and 34, and retaining

rings

35 and 36 such as a C-ring are attached thereto. As a result, the nuts 33 and 34 are prevented from rotating in the loosening direction at the positions where they come into contact with the retaining rings 35 and 36 as the restricting means, that is, at the positions shown in (2), whereby the nuts 33 and 34 of the

bolts

31 and 32 are blocked. Dropping from is prevented. On the other hand, when the tightened state by the

bolts

31 and 32 is released, the movement of the side cover 40 in the direction of the arrow 51, that is, the movement away from the guide bar 12 is allowed. For this reason, the clearance gap 54 between the side cover 40 and the main body housing 3 becomes large, and the fitting state of the fixing hole 3b and the protrusion 44 is also released. Further, since the tightening state of the guide bar 12 held between the side cover 40 and the main body housing 3 is released, the side cover 40 can move in the direction of the arrow 52.

FIG. 4 (3) shows a state after the side cover 40 is moved in the direction of the arrow 52 with respect to the main body housing 3. In this state, the protruding portion 44 of the side cover 40 is separated from the fixing hole 3b formed in the main body housing 3 to the rear side, that is, the state shown in FIG. Moreover, since the nuts 33 and 34 are located in the approximate center of the through

holes

42a and 43a, the side cover 40 can be removed. FIG. 4 (4) shows a state where the side cover 40 is moved in the direction of the arrow 53 from this state. The side cover 40 is formed with through holes (

circular holes

42a and 43a) large enough to allow the

bolts

31 and 32 and the nuts 33 and 34 as fixing means to pass therethrough, so that the

bolts

31 and 32 remain in the nuts 33 and 34. The side cover 40 can be removed from the main body housing 3 in the state (engaged state) as it is. Since the chain pulling boss 48 is provided on the side cover 40 side, the movement restriction of the guide bar 12 in the direction of the arrow 53 is released. In addition, the shape of the portion of the guide bar 12 through which the nuts 33 and 34 pass is not a hole shape, but is an elongated notch-shaped bolt fixing hole formed from the rear end side to the front side in the axial direction, or the side cover 40. If the shape is equivalent to the

holes

42 and 43, the guide bar 12 can be removed while the

bolts

31 and 32 are engaged with the nuts 33 and 34.

Next, a second embodiment of the present invention will be described with reference to FIGS. In the first embodiment, due to the provision of the tension adjusting mechanism 45 on the side cover 40 side, in the arrangement of the

holes

42 and 43, the large-diameter through

holes

42a and 43a are set as the front side, and locked to the rear side. The

holes

42b and 43b are connected to each other. With such an arrangement relationship, when the side cover 40 is moved rearward and the side cover 40 is removed, the tension adjusting mechanism 45 moves in a direction to loosen the tension of the saw chain. In the second embodiment, by disposing the tension adjusting mechanism 145 on the main body housing 103 side, the shapes of the

holes

142 and 143 of the side cover 140, particularly the arrangement of the through holes and the locking holes having a large diameter are different. Made possible. In the second embodiment, with respect to the first embodiment, the direction of movement of the side cover is reversed, and when the side cover 140 is removed, the side cover 140 is moved forward and then moved to the right. did. In order to realize this configuration, it is important that the brake mechanism 25 that operates in conjunction with the brake lever 7 and the tension adjustment mechanism 145 are provided on the main body housing 103 side.

FIG. 5 is a side view showing the structure of the chain saw 101 according to the second embodiment of the present invention, and a part thereof is shown in a perspective view. A centrifugal clutch mechanism 20 is provided on the right side of the main body housing 103, and a sprocket 24 is provided on the clutch drum 23. A mechanical brake mechanism 25 is provided on the outer peripheral surface of the centrifugal clutch mechanism 20. The brake mechanism 25 includes a brake band 26 positioned on the outer peripheral side of the clutch drum 23 and a link mechanism 27 that pulls the brake band 26. When the brake lever 7 is tilted forward, the link mechanism 27 operates to spring. The end of the brake band 26 is pulled by the force 28 and the clutch drum 23 is tightened, so that the rotation of the saw chain can be stopped. The tension adjustment mechanism 145 is provided on the lower side portion of the

bolts

31 and 32 on the main body housing 103 side.

6 is a cross-sectional view taken along the line BB in FIG. In FIG. 6, the centrifugal clutch mechanism 20 is fixed to the outer peripheral side of the crankshaft 11 and includes a clutch drum 23 and a clutch pawl 22 that rotates together with the crankshaft 11. A sprocket 24 is fixed to the clutch drum 23. When the rotational speed of the crankshaft 11 is less than the predetermined rotational speed, the clutch drum 23 and the crankshaft 11 are in a disconnected state. When the crankshaft 11 rotates and reaches a predetermined rotational speed or more, the outer peripheral portion of the clutch pawl 22 that swings around the swinging shaft by centrifugal force comes into contact with the inner peripheral side of the cylindrical clutch drum 23. The rotational force of the crankshaft 11 is transmitted to the clutch drum 23, and the sprocket 24 fixed to the clutch drum 23 rotates.

The tension adjusting mechanism 145 includes a long screw 146, a chain pulling boss 148 that is screwed into the thread of the long screw 146, and a bearing 147 that pivotally supports the end of the long screw 146. The chain pulling boss 148 is movable in the front-rear direction along the wall surface of the main body housing 103 by partly contacting the wall surface of the main body housing 103. The long screw 146 has a thread formed on the head 146a, and is disposed so as to penetrate the holding

portions

106a and 106b so as to penetrate the recessed portion 106 formed in the main body housing 3. The long screw 146 can be rotated with a screwdriver from the direction of the arrow 146a, and the rotation enables the chain pulling boss 148 to move in the front-rear direction. The chain pulling boss 148 engages with a round hole (not shown) formed in the guide bar 12, so that the guide bar 12 can be moved by moving the chain pulling boss 148.

FIG. 7 (1) is a side view of the chain saw 101 of the second embodiment, showing a state when the side cover 140 is moved and fixed to the rear side, and (1) is a side view. (2) is a partial cross-sectional view of the CC section. Here, the state in which the side cover 140 is located on the rear side is a state during the operation of the chain saw. Normally, some external force may be applied, such as a tree branch hitting the side cover 140, but in that case, an impact is often applied to the side cover 140 from the front side or the oblique side. Is a force to move the rearward side as indicated by an arrow 152. In the second embodiment, when the side cover 140 is moved to the rear side, the chain saw is in operation, so that there is a possibility that the side cover 140 may move even when an external force is applied to the side cover 140. Decrease significantly. The shapes of the

holes

142 and 143 are shapes in which the

holes

42 and 43 shown in FIG. That is, the rear sides of the

holes

142 and 143 are

circular holes

142a and 143a having a large diameter and allowing the nuts 33 and 34 to pass therethrough. As shown in (2), the points where the nuts 33, 34 are attached to the

bolts

31, 32, the point where threads (not shown) are formed on the outer peripheral surfaces of the

bolts

31, 32, the tips of the

bolts

31, 32 An annular continuous groove is formed in the vicinity, and retaining rings (C-rings) 35 and 36 are provided there, which is the same configuration as in the first embodiment.

8 is a view showing a state in which the side cover 140 is moved to the front side in order to remove the side cover 140 from the state of FIG. 7, (1) is a side view, and (2) is a partial cross-sectional view of the CC section. It is. Here, the side cover 140 moves forward as indicated by an arrow 153, and the

circular holes

142a and 143a of the

holes

142 and 143 and the nuts 33 and 34 are in alignment. As can be seen, elongated

holes

142b and 143b are formed in front of the circular holes 142a and 143a. (2) shows a state in which the nuts 33 and 34 are loosened to the maximum until they come into contact with the retaining rings (C rings) 35 and 36. In this state, since the distance between the seating surfaces of the nuts 33 and 34 and the recessed portion 141 of the side cover 140 is greatly separated, the tightening force of the side cover 140 on the guide bar 12 is eliminated. Can do.

According to the second embodiment, since the tension adjusting mechanism 145 that adjusts the tension of the saw chain is disposed on the main body housing 103 side, the moving direction when the side cover 140 is removed should be forward of the fixed position. Can do. In the second embodiment, as in the first embodiment, the moving direction when the side cover 140 is removed can be forward of the fixed position, or the other direction, for example, the removal of the side cover 140 can be performed. The moving direction at the time may be above or below the fixed position.

As mentioned above, although this invention was demonstrated based on the Example, this invention is not limited to the above-mentioned Example, A various change is possible within the range which does not deviate from the meaning. For example, the fixing means for fixing the side cover so as to penetrate through the through hole is not constituted by a bolt and a nut extending from the main body housing side, but a shaft portion having a male screw extending from the main body side and a resin screwed to the shaft portion You may comprise by the fastener member formed by etc. A hole having a female screw may be provided on the main body side, and a bolt or the like may be inserted into the side cover 40 and the guide bar 12 and then screwed into the female screw on the main body side to be fixed. Further, in the first embodiment, a bottom plate that is formed separately from the side cover 40 and is movable in the surface direction with respect to the side cover 40 is provided on the bottom surface (the surface sandwiched by the nuts) of the hollow portion 41. It is good also as a structure. In this case, a through hole having a size that allows the nuts 33 and 34 to pass therethrough is provided on the bottom surface of the recessed portion 41, and a locking hole and a through hole are provided on the bottom plate. In this case, the bottom plate is moved, and the

bolts

31 and 32 are passed through both the through holes on the bottom surface and the locking holes on the bottom plate and fixed. When removing the side cover 40 from the main body housing, the nuts 33 and 34 are moved by moving only the bottom plate so that the through holes of the bottom plate are located at the positions of the nuts 33 and 34 without moving the entire side cover 40. It is possible to pass through both the through hole on the bottom plate and the through hole on the bottom surface, and the side cover 40 can be removed while the nuts 33 and 34 are attached to the

bolts

31 and 32. Further, the locking hole may be configured to extend to the side surface of the recessed portion 41, and the through hole connected to the locking hole may be provided on the side surface of the recessed portion 41. In this case, when removing the side cover 40, the nuts 33 and 34 can be passed through the through hole only by moving the side cover 40 up and down or front and rear, and the side cover can be removed from the main body housing. Moreover, it is good also as a structure extended so that a latching hole may be connected with either the up-and-down or front-back edge of a side cover. In this case, the side cover can be removed from the main body housing simply by moving the side cover up and down or in the front-rear direction so that the bolt can be extracted from the edge through the locking hole.

DESCRIPTION OF SYMBOLS 1 ... Chain saw, 3 ... Main body housing, 3b ... Fixing hole (recessed part), 4 ... Rear handle, 5 ... Front handle, 6 ... Top cover, 7 ... Brake lever, 8 ... Trigger lever, 9 ... Lock lever, 10 ... Engine, 11 ... Crankshaft, 12 ... Guide bar, 12b ... Fitting hole, 13 ... Spike, 20 ... Centrifugal clutch mechanism, 22 ... Clutch claw, 23 ... Clutch drum, 24 ... Sprocket, 25 ... Brake mechanism, 26 ... Brake Band, 27 ... Link mechanism, 28 ... Spring, 31, 32 ... Bolt, 33, 34 ... Nut, 35, 36 ... Retaining ring, 37, 38 ... Continuous groove, 40 ... Side cover, 40b ... Rear end face, 41 ... Recess Part, 42, 43 ... hole, 42a, 43a ... circular hole (through hole), 42b, 43b ... long hole (locking hole), 44 ... projection, 45 ... tension adjusting mechanism 46 ... long screw, 47 ... nut part, 48 ... chain pulling boss, 54 ... gap, 101 ... chain saw, 103 ... main body housing, 106 ... hollow part, 106a, 106b ... holding part, 140 ... side cover, 141 ...

hollow part

142, 143 ... holes, 142a, 143a ... circular holes, 142b, 143b ... long holes, 145 ... tension adjusting mechanism, 146 ... long screws, 146a ... head, 147 ... bearings, 148 ... chain pulling boss, 201 ... Chain saw, 203 ... Body housing, 203b ... Mounting surface, 231,232 ... Bolt, 233,234 ... Nut, 240 ... Side cover, 241 ... Dimple, 241a ... Holding surface, 242,243 ... Bolt hole

Claims

A saw chain, a guide bar that is mounted on the main body housing and over which the saw chain is stretched, a drive source that drives the saw chain, a sprocket that transmits a rotational force from the drive source to the saw chain, and a part of the guide bar; A chain saw that includes a side cover for covering the sprocket and fixing the guide bar to the main body housing, and the main body housing is provided with a fixing means for fixing the side cover with screws, Has a through-hole through which the fixing means can pass.
A locking hole is formed to connect to the through hole and engage with the fixing means, the fixing means is passed through the through hole, and the side cover is moved in the surface direction of the guide bar. The chain saw according to claim 1, wherein the fixing means is fixed to the locking hole.
The fixing means includes a bolt extending perpendicular to a side surface of the main body housing, and a nut attached to the bolt. The locking hole extends from the through hole toward one side in a radial direction, and has a short diameter. 3. An oval cutout that is smaller than the two-surface width of the nut, and the fixing by the fixing means is performed by clamping the nut to the bolt and holding the outer periphery of the locking hole. Chain saw described in
The bolt has an attachment shaft extending from the main body housing through the attachment hole of the guide bar so as to penetrate the locking hole of the side cover, and after the nut is attached to the attachment shaft 4. A restricting means for preventing the nut from coming off from the mounting shaft is provided, and the side cover can be removed from the main body housing in a state where the nut is engaged with the bolt. The described chain saw.
A male screw is formed on the outer periphery of the mounting shaft of the bolt, a continuous groove continuous in the circumferential direction is formed near the tip, and the restricting means is a retaining ring fitted in the continuous groove. The chain saw according to claim 4.
The side holes are disposed so that the longitudinal direction is parallel to the longitudinal direction of the guide bar, and the mounting shaft is moved from the inside of the through hole to the inside of the fastening hole. The chain saw according to claim 5, wherein the guide bar is movable in a longitudinal direction of the guide bar.
The side cover is provided with a tension adjusting means for adjusting the tension of the saw chain by moving the guide bar in the front-rear direction with respect to the main body housing, and the locking hole is located behind the through hole. The chain saw according to claim 6, wherein the saw chain is loosened by the tension adjusting means when the side cover is removed.
The main body housing and the side cover are provided with a concave portion or a convex portion, and when the side cover is fixed, the concave portion and the convex portion are fitted to suppress relative movement in the front-rear direction. The chain saw according to Item 7.
A brake for suppressing rotation of the sprocket and tension adjusting means for adjusting the tension of the saw chain are provided on the main body housing side, and the locking hole is arranged to extend to the front side of the through hole. The chain saw according to claim 6.
A saw chain, a guide bar that is mounted on the main body housing and over which the saw chain is stretched, a drive source that drives the saw chain, a sprocket that transmits a rotational force from the drive source to the saw chain, and a part of the guide bar; A chain saw that covers the sprocket and includes a side cover for fixing the guide bar to the main body housing, a first fixing member provided on the main body housing, and attached to the first fixing member. A second fixing member that fixes the side cover to and from the main body housing, and the side cover is detachable from the main body housing with the second fixing member attached to the first fixing member. A chain saw characterized by the construction of