JP2014213514A - Chain saw - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make it possible to easily detach a nut or to surely fasten the nut even when the corner part of the nut for fitting a side cover to a main body housing wears to become useless.SOLUTION: A chain saw is provided with: a sprocket and a chain bar 3 provided in a main body housing 1; a saw chain 4 bridging the sprocket and the chain bar 3; a side cover 10 covering the sprocket; and fitting means for fitting the side cover 10 to the housing 1. The fitting means has: a male screw of a bolt 30 protruding from the housing 1; a fitting hole of the side cover 10; a cover member 40 for preventing the dropout of the nut removably fixed to the outer face of the side cover 10; and a flanged nut 50 which is housed inside the cover member 40 and is screwed with the male screw.

Description

  The present invention relates to a chain saw that cuts wood or the like, and more particularly, to an attaching means having a function of preventing a nut from falling off a side cover that covers a sprocket.

  Usually, a chain saw has a saw chain wound around the outer periphery of a chain bar, and is provided with a sprocket that is driven by the rotational power of an engine mounted on a main body housing in order to drive the saw chain. When the sprocket is engaged between the chain rings of the saw chain, the saw chain is driven. A side cover that covers the sprocket region is screwed to the main body housing. Since this side cover may be removed when the chain bar or the saw chain is replaced, it is fixed by fastening a nut that can be easily attached and detached by the user. When removing the side cover, an operation of loosening a nut fixing the side cover is performed (for example, see Patent Document 1). At this time, the loosened nut may be dropped and lost. In order not to cause such a situation, it is necessary to prevent the nut from falling off the side cover.

  On the other hand, for example, as a structure for preventing the nut from being lost, a method using a special nut that can be engaged with the side cover is conceivable.

JP 2009-279883 A

  However, in the case of the above structure, the effect of preventing the loss of the nut can be obtained, but when removing and attaching the nut, the hexagonal portion of the nut is licked and becomes useless, There is a problem that it is difficult to remove the nut. In addition, since it cannot be easily removed, if foreign matter such as dust enters the gap formed between the sleeve portion and the opening, it may be difficult to remove and collect and the nut may not be sufficiently tightened.

  Therefore, the present invention has been made in view of the above-described problems, and the object thereof is easily achieved even when the corners of the nut for attaching the side cover to the main body housing are licked and become useless. It is an object of the present invention to provide a chainsaw having a nut drop-off preventing function capable of removing a nut and securely tightening the nut.

One embodiment of the present invention is a chainsaw. The chain saw includes a main body housing, a sprocket disposed on a side surface of the main body housing, a chain bar attached to the side surface of the main body housing, a saw chain spanned over both the sprocket and the chain bar, A side cover that covers the sprocket, and mounting means for attaching the side cover to the main body housing,
The attachment means includes at least one male screw portion projecting from the side surface of the main body housing, an attachment hole through which the male screw portion is formed in the side cover, a nut screwed into the male screw portion, and the side cover. And a cover member that is provided on the opposite side of the surface facing the main body housing and restricts the nut from falling off.

  The said aspect WHEREIN: The said nut is comprised as a nut with a flange, There is the space which accommodates the said nut with a flange between the said cover member and the said side cover, The head of the said nut with a flange can pass through the said cover member And the said flange part is good to have an opening which cannot pass.

  In the above aspect, the cover member may be detachably attached to the side cover.

  In the above aspect, the cover member may be provided with a foreign matter discharge notch through which the nut does not pass.

  In the above aspect, an urging unit that urges the side cover and the nut in a direction to separate them may be provided.

  The said aspect WHEREIN: It is good for the one side of the said cover member to be attached to the said side cover by uneven | corrugated engagement.

  In the above aspect, an attachment surface of the cover member is formed on an outer surface of the side cover, and the attachment surface is lower than the periphery, and the height of the cover member is the same as or higher than the periphery of the attachment surface. It may be the following.

  It should be noted that any combination of the above-described constituent elements, and those obtained by converting the expression of the present invention between methods and systems are also effective as aspects of the present invention.

  According to the present invention, the cover member can normally prevent the nut for attaching the side cover to the main body housing from falling off the side cover with the cover member, but when the corner portion of the nut licks and becomes useless Can easily remove the nut from the side cover by removing the cover member. Further, foreign matters such as dust can be easily performed with the nut removed, and the nut can be securely tightened.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a right side view showing a rear handle type engine chain saw that is a first embodiment of a chain saw according to the present invention and that has a function of preventing nut dropout. The side cover attachment part enlarged view in 1st Embodiment. FIG. 2 is a side cover attaching means having a function of preventing nut drop in the first embodiment, and is a cross-sectional view taken along line AA in FIG. FIG. 2 is a side cover attaching means having a function of preventing nut drop in the first embodiment, and is a cross-sectional view taken along line AA in FIG. 1 (when the nut is not fastened); FIG. 6 is a side cover attaching means having a nut dropping prevention function according to the second embodiment of the present invention, and is a cross-sectional view taken along the line AA in FIG. FIG. 6 is a side cover attaching means having a function of preventing nut drop in the second embodiment of the present invention, and is a cross-sectional view taken along line AA in FIG. 1 (when the nut is not fastened); The side cover attachment part enlarged view in the 3rd Embodiment of this invention. The side cover attachment part enlarged view in the 4th Embodiment of this invention.

  Hereinafter, preferred 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 or equivalent component, member, process, etc. which are shown by each drawing, and the overlapping description is abbreviate | omitted suitably. In addition, the embodiments do not limit the invention but are exemplifications, and all features and combinations thereof described in the embodiments are not necessarily essential to the invention.

  A first embodiment of the present invention will be described with reference to FIGS. 1 to 4 by taking a rear handle type engine chain saw as an example. FIG. 1 shows a rear handle type engine chain saw provided with a side cover attaching means having a function of preventing nut drop. This engine chain saw has a main body housing 1, and an engine serving as a power source (not shown) is provided in the main body housing 1. It is arranged. A sprocket 2 that is rotationally driven by an engine is disposed on a side surface of the main body housing 1. A chain bar 3 is attached to the side surface of the main body housing 1 in a state of protruding in the forward direction X of the main body housing 1, and an annular saw chain 4 is bridged on the outer peripheral portions of the sprocket 2 and the chain bar 3. Has been. The sprocket 2 is engaged between the chain rings of the saw chain 4 to interlock the saw chain 4, and the saw chain 4 is guided by the outer periphery of the chain bar 3 as the sprocket 2 rotates. . The interlocking portion of the sprocket 2 and the saw chain 4 is covered with a side cover 10 attached to the side surface of the main body housing 1.

  A front handle 5 is disposed at an upper center portion of the main body housing 1, and a rear handle 6 is disposed on a back surface portion opposite to the chain bar 3. The operator holds the front handle 5 with the left hand and holds the rear handle 6 with the right hand, thereby carrying the chain saw body and carrying out the work.

  Next, details of the side cover attaching means 20 having a function of preventing the nut from falling off for attaching the side cover 10 to the main body housing 1 will be described with reference to FIGS. 2 shows an enlarged view of the attachment part of the side cover 10 of FIG. 1, FIG. 3 shows a cross-sectional view taken along the line AA in FIG. 1, and FIG. 4 shows a cross-sectional view taken along the line AA of FIG. (When nut is not fastened)

  The side cover attaching means 20 having a function of preventing the nut from falling off includes a bolt 30 fixed to the main body housing 1, an attachment hole (through hole) 11 formed in the side cover 10 through which the male screw portion of the bolt 30 is inserted, and a side cover 10 includes a cover member 40 for preventing a drop-off of a nut, which is detachably mounted on the opposite side of the surface facing the main body housing 1, and a nut 50 with a flange which is screwed into the male screw portion.

  The head of the bolt 30 is embedded and fixed in the main body housing 1, and the male thread portion (screw free end) of the bolt 30 projects vertically from the side surface 1 a of the main body housing 1. On the opposite side of the surface of the side cover 10 facing the main body housing 1, that is, on the outer surface which is a non-facing surface, a step surface 12 (being a mounting surface for the cover member 40) which is one step lower than the surroundings is formed. A mounting hole 11 is formed in 12. Further, the mounting portions 41 on both sides of the cover member 40 are fixed to the stepped surface 12 with screws 60 as detachable fixing means.

  The nut dropping prevention cover member 40 has a ceiling plate portion 42 that is parallel to the stepped surface 12 of the side cover 10 at a predetermined height position, and the space 43 that can accommodate the flanged nut 50 is formed with the stepped surface 12. Formed between. An opening 44 through which the hexagonal head 51 of the nut 50 can be inserted is formed in the ceiling plate portion 42. The opening 44 is a circular hole that is larger than the hexagonal head 51 of the nut 50 and smaller than the flange portion 52 formed integrally with the nut 50. The flange portion 52 serves as a stopper for preventing the nut 50 from falling off, and serves as a role for sliding along the inner shape (inner peripheral shape) of the cover member 40 and maintaining the posture of the nut 50. Yes. A foreign matter discharge notch 45 is provided on the lower side of the cover member 40 when the engine chainsaw is in an upright state. The foreign matter discharge notch 45 has a shape and dimension that does not allow the flange portion 52 to pass therethrough. When foreign matter such as cutting chips or dust enters from the opening 44, the foreign matter is discharged from the foreign matter discharge notch 45 in the arrow direction Y due to its own weight.

  The cover member 40 for preventing nut drop is attached to the stepped surface 12 of the side cover 10 with a screw 60 serving as a fixing means that can be removed from the side cover 10 in a state in which the nut 50 with flange is accommodated inside. . Note that the step surface 12 serving as the mounting surface of the cover member 40 is lower than the surroundings, and the height of the cover member 40 is set to be equal to or lower than the height around the step surface 12.

  If the chain bar 3 is arranged between the side surface 1 a of the main body housing 1 and the side cover 10 and the flanged nut 50 is screwed to the bolt 30, the nut 50 contacts the stepped surface 12 of the side cover 10. As a result, the nut 50 presses the side cover 10 against the side surface 1 a, and as a result, the chain bar 3 is fastened and fixed between the main body housing 1 and the side cover 10.

  On the other hand, when the nut 50 with the flange is removed from the bolt 30 in order to remove the side cover 10 from the main body housing 1, even if the nut 50 is about to come out of the side cover 10, the flange portion 52 provided on the nut 50 is the cover member. It abuts on the inside of the edge of the opening 44 of the 40. As a result, the nut 50 can be prevented from falling off the side cover 10.

  According to the present embodiment, the following effects can be achieved.

(1) A space 43 for housing the flanged nut 50 is provided between the side cover 10 and the cover member 40 for preventing the nut from falling off, and the cover member 40 is detachably attached to the side cover 10 and the cover member 40 is flanged. By forming an opening 44 through which the head portion 51 of the nut 50 can pass and the flange portion 52 cannot pass through, the dropout of the flanged nut 50 accommodated in the space 43 from the side cover 10 is reliably prevented. Can do.

(2) Since the cover member 40 is held on the side cover 10 by a fixing means that can be removed from the side cover 10, the cover member 40 can be easily removed. Even if it becomes obsolete due to licking, the nut 50 can be easily removed by removing the cover member 40.

(3) Even if foreign matter such as cutting chips or dust enters the opening 44, it is discharged at any time by the foreign matter discharge notch 45 provided in the cover member 40. Can be tightened.

(4) A step surface 12 is formed on the outer surface of the side cover 10 as an attachment surface of the cover member 40. The step surface 12 is lower than the surroundings, and the height of the cover member 40 is a height around the step surface 12. Therefore, the cover member 40 does not protrude beyond the outer surface of the side cover 10 and the operability is not impaired.

  5 and 6 show a second embodiment of the present invention. In the first embodiment described above, the posture of the nut 50 is maintained by sliding the flange portion 52 of the flanged nut 50 along the inner peripheral shape of the nut dropping prevention cover member 40. In this embodiment, in addition to the configuration of the first embodiment described above, an annular groove portion 13 is provided around the mounting hole 11 of the side cover 10 and a coil spring 14 serving as a biasing means is provided so as to fit in the groove portion 13. It is arranged.

  In this case, since the coil spring 14 biases the side cover 10 and the nut 50 in a direction away from each other, there is an advantage that the posture of the nut 50 is reliably held when the nut 50 is not fastened. Other configurations and operational effects are the same as those in the first embodiment.

  FIG. 7 shows a third embodiment of the present invention. In the first embodiment described above, the mounting portions 41 on both sides of the cover member 40 for preventing nut drop are fixed using two screws 60 as fixing means. In this embodiment, A convex portion 48 is formed by integral molding on a part of the cover member 40, and a hooking concave portion 18 by integral molding is provided on the step surface 12 of the side cover 10, and the convex portion 48 engages (fits) with the hook concave portion 18. Thus, one screw 60 is used as a fixing means, and the attachment portion 41 on one side of the cover member 40 is attached to the side cover 10.

  In this case, since one side of the cover member 40 is attached to the side cover 10 by concave-convex engagement, only one screw 60 is required to attach the other side of the cover member 40, so that the cover member 40 can be attached and detached more easily. become.

  FIG. 8 shows a fourth embodiment of the present invention. In the first embodiment described above, the side cover mounting means 20 has a configuration in which each of the bolt 30 and the nut 50 for mounting the side cover 10 is provided. However, in the present embodiment, the side cover 10 A plurality of sets of bolts 30 and nuts 50 for attaching the nuts are provided. One cover member 40A for preventing nut dropout is provided in common for the plurality of sets. The function of the cover member 40A is the same as that of the first embodiment.

  The present invention has been described above by taking the embodiment as an example. However, it is understood by those skilled in the art that various modifications can be made to each component and each processing process of the embodiment within the scope of the claims. By the way. Hereinafter, modifications will be described.

  In each of the embodiments, the present invention is applied to the side cover attaching means attached to the rear handle type engine chain saw. However, the present invention is not limited to this. For example, a top handle type engine chain saw or an electric motor is used as the power source. The present invention can also be applied to side cover attachment means attached to a chain saw or the like.

DESCRIPTION OF SYMBOLS 1 Main body housing 1a Side surface 2 Sprocket 3 Chain bar 4 Saw chain 5 Front handle 6 Rear handle 10 Side cover 11 Mounting hole 12 Step surface 13 Groove part 14 Coil spring 18 Hooking recessed part 20 Side cover attachment means 30 Bolt 40, 40A Cover member 41 Attachment Portion 42 ceiling plate portion 43 space 44 opening 45 foreign matter discharge notch 48 convex portion 50 flanged nut 51 head 52 flange portion 60 screw

Claims (7)

A body housing;
A sprocket disposed on a side surface of the main body housing;
A chain bar attached to the side surface of the body housing;
A saw chain that spans both the sprocket and the chain bar;
A side cover covering the sprocket;
Mounting means for attaching the side cover to the body housing;
The attachment means includes at least one male screw portion projecting from the side surface of the main body housing, an attachment hole through which the male screw portion is formed in the side cover, a nut screwed into the male screw portion, and the side cover. And a cover member that is provided on the opposite side of the surface facing the main body housing and restricts the nut from falling off.   The nut is configured as a nut with a flange, and there is a space for accommodating the nut with the flange between the cover member and the side cover, and the cover member allows a head of the nut with the flange to pass through the flange. The chain saw according to claim 1, wherein the portion has an opening through which the portion cannot pass.   The chain saw according to claim 1 or 2, wherein the cover member is detachably attached to the side cover.   The chain saw according to any one of claims 1 to 3, wherein the cover member is provided with a foreign matter discharge notch through which the nut does not pass.   The chain saw according to any one of claims 1 to 4, further comprising an urging unit that urges the side cover and the nut in a direction to separate them.   The chain saw according to any one of claims 1 to 5, wherein one side of the cover member is attached to the side cover by uneven engagement.   An attachment surface of the cover member is formed on the outer surface of the side cover, the attachment surface is lower than the surroundings, and the height of the cover member is equal to or less than the height of the surroundings of the attachment surface. The chain saw according to any one of claims 1 to 6, wherein

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