JP2013031931A - Portable work equipment - Google Patents

Abstract

An object of the present invention is to facilitate an attaching operation of a vibration isolator between a first member and a second member.
An attachment portion is provided at one end of a coil spring 32, and the coil spring 32 is fixed to the base with a tapping screw at the attachment portion. A screwed portion 35a is provided on the outer periphery of the connecting member 35, and the other end of the coil spring 32 is screwed and attached to the screwed portion 35a. The connecting member 35 is provided with a bolt 36 coaxially with the screwed portion 35a, and the shaft portion 36b of the bolt 36 is inserted into the mounting hole of the housing. The connecting member 35 is provided with an engaging portion 41 configured as a two-sided width so that the tool 43 can be engaged from the radial side of the screwed portion 35a. When the nut 36 is fastened to the shaft portion 36b of the bolt 36 and the connecting member 35 is fixed to the housing, the connecting member 35 is held in the rotational direction by the tool 43 engaged with the engaging portion 41.
[Selection] Figure 7

Description

  The present invention relates to a portable work machine such as a chain saw or a hedge trimmer, and more particularly to a machine equipped with a vibration isolating device between a drive source and a handle.

  As a portable working machine that processes an object to be processed by a processing blade driven by a drive source, for example, there is a chain saw also called a power saw. The chain saw is equipped with an endless saw chain as a processing blade. The saw chain is driven by a drive source to operate, and the operated saw chain is pressed against an object to be processed such as a tree trunk or a branch. Can be done.

  A two-cycle gasoline engine or the like is often used as a drive source for the work machine. The drive source is housed in a housing, and a base is attached to the housing. The base is provided with a front handle and a rear handle, and an operator can work by holding these handles.

  In order to suppress the vibration of the processing blade and the driving source from being transmitted to the worker via the handle and reduce the burden on the worker, a work machine provided with a vibration isolating device between the housing and the base is provided. Are known. In this case, the connecting member having a helical screw groove is fixed to the housing by a bolt and a nut provided coaxially with the screw portion, and one end of the coil spring is screwed and fixed to the screw portion. Is fixed to the base by a screw member. Thereby, the housing and the base are connected by the coil spring, and the vibration transmitted to the operator through the handle is absorbed by the coil spring.

  In such an anti-vibration device, since the connection member into which one end of the coil spring is screwed is fixed to the housing with a bolt and a nut, when the nut is tightened to the bolt, the connection member rotates together with the nut, There is a possibility that the screwing amount of the coil spring into the connecting member may deviate from the specified value. If the screwing amount of the coil spring into the connecting member deviates from the specified value, the effective length of the coil spring, that is, the spring constant, changes, and the desired vibration absorption effect may not be obtained or the housing may not be held on the base. There is.

  Thus, for example, in the working machine disclosed in Patent Document 1, a slit is provided on the tip surface of a bolt for fixing the connecting member to the housing, and a tool such as a minus driver is engaged with the slit from the axial direction. The nut can be tightened while keeping the bolt from rotating.

Japanese Patent Application No. 2010-041606

  However, in the structure shown in Patent Document 1, it is necessary to engage the tool from the axial direction with the slit on the front end surface of the bolt and to engage the tool with the nut and operate these tools on the same side with respect to the housing. Therefore, it is difficult to attach a coil spring between the housing and the base.

  Further, when the nut is tightened to the bolt, it is necessary to engage the tool from the axial direction with the slit on the front end surface of the bolt, so that a torque wrench cannot be used as a tool for tightening the nut.

  An object of the present invention is to facilitate the mounting work of the vibration isolator between the first member and the second member.

  A portable work machine according to the present invention is a portable work machine that processes an object to be processed by a processing blade driven by a drive source, and is held by a worker and a first member to which the drive source is attached. The first member or the second member is provided at one end in the axial direction by a second fastening member provided with a handle and a spiral screw-in portion and provided coaxially with the screw-in portion. A connection member fixed to one side, one end screwed into the screw-in portion and attached to the connection member, and the other end fixed to the other of the first member or the second member by a second fastening member An engaging portion that can be engaged with a tool from the radial side of the screwed portion, and the connecting member is rotated by the tool engaged with the engaging portion. It was possible to hold in the direction And features.

  The portable work machine of the present invention is characterized in that the first fastening member is constituted by a bolt and a nut.

  The portable work machine according to the present invention is characterized in that the engaging portion includes a pair of engaging surfaces provided to face each other.

  The portable working machine of the present invention is characterized in that the engaging portion is formed of a polygonal column.

  In the portable work machine according to the present invention, the engaging portion is configured as a hole that opens in a radial direction.

  The portable work machine according to the present invention is characterized in that the engaging portion is provided on one side in the axial direction with respect to the screwed portion.

  The portable work machine according to the present invention is characterized in that the engaging portion is provided on the other side in the axial direction with respect to the screwed portion.

  According to the present invention, since the engaging portion is provided on the connecting member so that the tool can be engaged from the radial direction of the screwed portion, the engaging portion is used when the connecting member is fastened by the first fastening member. The connecting member can be held so as not to rotate by the tool engaged with the. Therefore, it is possible to perform the fastening operation of the first fastening member while holding the connection member so as not to rotate with the tool engaged with the engaging portion, and the coil between the first member and the second member The work of attaching the spring can be facilitated.

It is a side view of the chainsaw which is one embodiment of the present invention. It is the perspective view which looked at the chainsaw shown in FIG. 1 from the bottom face side. It is a disassembled perspective view of the vibration isolator shown in FIG. It is sectional drawing of the vibration isolator shown in FIG. It is sectional drawing which follows the AA line in FIG. It is sectional drawing which follows the BB line in FIG. It is sectional drawing which shows the state which engaged the tool with the engaging part of the connection member. It is a modification of the engaging part shown in FIG. 5, Comprising: It is sectional drawing which shows the case where an engaging part is comprised by the polygonal column. FIG. 6 is a cross-sectional view showing a modification of the engaging portion shown in FIG. 5, wherein the engaging portion is configured as a hole that opens in the radial direction.

  Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings.

  A chain saw 11 shown in FIG. 1 is a portable working machine also called a power saw, and is used for cutting an object to be processed such as a tree trunk or a branch.

  The chainsaw 11 includes a resin housing 12 as a first member, and an engine 13 as a drive source is attached to the housing 12. The housing 12 is also called an engine case, and the engine 13 is accommodated in the housing 12. A two-cycle gasoline engine is used as the engine 13, and this engine is arranged vertically in the housing 12.

  A side case 14 is fixed to the side surface of the housing 12, and a guide bar 15 is sandwiched and fixed between the housing 12 and the side case 14. The guide bar 15 is formed in a long plate shape by a metal such as a steel material, and is clamped and fixed between the housing 12 and the side case 14 on the base end side, and the front end side protrudes forward from the housing 12. Yes. The outer peripheral edge of the guide bar 15 is formed in a rail shape, and a saw chain 16 as a processing blade is stretched around the outer peripheral edge. The saw chain 16 is stretched over a sprocket (not shown) disposed in the side case 14, and this sprocket is connected to a crankshaft of the engine 13 via a centrifugal clutch (not shown).

  When the engine 13 operates and the rotation speed of the crankshaft exceeds a predetermined rotation speed, the centrifugal clutch is switched to the power transmission state, and the sprocket is driven and rotated by the engine 13. When the sprocket rotates, the saw chain 16 stretched over the sprocket operates along the outer peripheral edge of the guide bar 15. In this manner, the workpiece can be cut by pressing the saw chain 16 driven by the engine 13 and operating along the outer peripheral edge of the guide bar 15 against the workpiece such as a tree trunk or a branch. it can.

  The housing 12 is attached to a base 21 as a second member. The base 21 is formed of a resin material. A rear handle (rear grip) 22 is integrally provided on the rear side, and a front handle (front grip) 23 is attached to the front side by a screw member. The operator can carry the chain saw 11 by holding these handles 22 and 23. A hand guard 24 is provided in front of the front handle 23 to protect the operator's hand holding the front handle 23. The rear handle 22 is provided with a throttle lever 25, and the rotation speed of the engine 13 can be controlled by operating the throttle lever 25. Reference numeral 26 denotes a lock lever provided on the rear handle 22, and an operator can operate the throttle lever 25 only in a state where the operator grips the rear handle 22 and the lock lever 26 is pushed.

  As shown in FIG. 2, a vibration isolator 31 is provided between the housing 12 and the base 21. The vibration isolator 31 suppresses the vibration generated between the saw chain 16 and the workpiece and the vibration generated by the engine 13 from being transmitted from the housing 12 to the base 21, via the handles 22 and 23. Transmission of vibration to the worker is suppressed.

  In FIG. 2, only one vibration isolator 31 is shown, but the chain saw 11 is provided with three vibration isolator 31 between the housing 12 and the base 21. A housing 12 is attached to the base 21. Since these anti-vibration devices 31 have basically the same configuration, the anti-vibration device 31 shown in FIG. 2 will be described below.

  As shown in FIGS. 3 and 4, the vibration isolator 31 includes a coil spring 32. The coil spring 32 is configured as a compression coil spring having a winding portion 32a having a predetermined number of turns and having a gap between the winding portions 32a, and at one end in the axial direction than the winding portion 32a. A mounting portion (pig tail end) 32b having a small winding diameter (radial dimension) is integrally provided. A tapping screw 33 as a second fastening member is inserted into the attachment portion 32b of the coil spring 32 from the inside of the winding portion 32a, and the tapping screw 33 is screwed into an attachment hole 34 provided in the base 21. The coil spring 32 is fixed to the base 21 by a tapping screw 33 at a mounting portion 32b provided at one end thereof.

  The second fastening member for fixing the coil spring 32 to the base 21 is not limited to the tapping screw 33 shown in the figure, and other fastening members such as bolts and nuts may be used.

  The other end of the coil spring 32 is fixed to the housing 12 via a connection member 35. The connecting member 35 is formed of a resin material in a cylindrical shape, and a screwed portion 35a is integrally formed on the outer peripheral portion thereof. The threaded portion 35a is formed as a spirally recessed groove, and its outer diameter dimension is set to a value substantially the same as the inner diameter dimension of the winding portion 32a of the coil spring 32, and the pitch is the winding portion of the coil spring 32. It is set to the same value as the pitch of 32a. Further, the axial dimension of the screw-in portion 35 a is set smaller than the axial dimension of the coil spring 32.

  One end of the coil spring 32 opposite to the side on which the mounting portion 32b is provided is screwed into the screwed portion 35a and attached to the connecting member 35. The coil spring 32 screwed into the threaded portion 35 a is disposed coaxially with the connection member 35 and is fixed in the axial direction with respect to the connection member 35.

  Note that the screwing amount of the coil spring 32 into the screwed portion 35a is adjusted to be a predetermined value set in advance so that the effective length of the coil spring 32, that is, the spring constant, becomes a desired value.

  Bolts 36 are embedded in the connection member 35 by means such as insert molding. The bolt 36 is disposed coaxially with the screw-in part 35 a, the head part 36 a is disposed inside the screw-in part 35 a, and the shaft part 36 b faces away from the attachment part 32 b of the coil spring 32 of the connection member 35. It protrudes from one end in the axial direction. An attachment hole 37 for attaching the connection member 35 is provided in the housing 12, and a shaft portion 36 b of the bolt 36 protruding from one end of the connection member 35 is inserted into the attachment hole 37. A nut 38 is screwed to the tip of the bolt 36 that protrudes from the mounting hole 37 of the shaft portion 36 b, and the nut 38 and the bolt 36 allow the connecting member 35 to be in contact with the housing 12 at one end surface 35 b in the axial direction. And is fixed to the housing 12. That is, the connecting member 35 is fixed to the housing 12 at one end in the axial direction by the bolt 36 and the nut 38 as the first fastening member disposed coaxially with the screwed portion 35a.

  Thus, one end of the coil spring 32 is fixed to the base 21 by the tapping screw 33, and the other end is fixed to the housing 12 via the connection member 35. Since the intermediate portion of the coil spring 32 can be expanded and contracted between the base 21 and the connecting member 35, vibration generated between the saw chain 16 and the object to be processed and vibration generated by the engine 13 are reduced with the housing 12. It can be absorbed by the expansion and contraction of the coil spring 32 connecting the base 21.

  When the screwing amount of the coil spring 32 into the connection member 35 deviates from the specified value, the effective length of the coil spring 32, that is, the spring constant, changes, and a desired vibration absorbing effect cannot be obtained. May not be able to hold. Therefore, when the connection member 35 into which the coil spring 32 is screwed is fixed to the housing 12 with the bolt 36 and the nut 38, it is necessary to prevent the connection member 35 from rotating by tightening the nut 38.

  In the present invention, the connection member 35 is provided with a pair of engaging portions 41, 42, and the nut 38 while preventing the connection member 35 from rotating by the tool 43 engaged with either of the engaging portions 41, 42. Can be tightened.

  One engaging portion 41 provided in the connecting member 35 is provided so as to protrude in the axial direction with respect to the screwed portion 35a on one side in the axial direction from which the shaft portion 36b of the bolt 36 protrudes with respect to the screwed portion 35a. . The engaging portion 41 is formed integrally with the screwed portion 35a. The engaging portion 41 includes a cylindrical portion 41a that is coaxial with the screwed portion 35a, and is parallel to the outer peripheral surface of the cylindrical portion 41a as shown in FIG. 5, and in the axial direction of the screwed portion 35a and the bolt 36. Is also provided with a pair of engaging surfaces 41b which are parallel to each other. That is, the engaging portion 41 is configured to have a two-surface width provided with a pair of engaging surfaces 41b facing the outer peripheral surface of the cylindrical portion 41a coaxial with the screwed portion 35a. As shown in FIG. 7, a fastening tool 43 such as a spanner can be engaged with the engaging portion 41 from the radial side of the screwed portion 35a. Then, the connecting member 35 can be held in the rotational direction around the axis of the screwed portion 35a by the tool engaged with the engaging portion 41, and the rotation can be prevented.

  The connecting member 35 is also provided with an engaging portion 42 on the other side in the axial direction facing the mounting portion 32b of the coil spring 32 with respect to the screwed portion 35a. The engaging portion 42 is provided so as to protrude in the axial direction with respect to the screwed portion 35a, and is formed integrally with the screwed portion 35a. The engaging portion 42 also includes a cylindrical portion 42a that is coaxial with the screwed portion 35a, and is parallel to the outer peripheral surface of the cylindrical portion 42a, as shown in FIG. 6, and the axial direction of the screwed portion 35a and the bolt 36. In addition, a pair of engaging surfaces 42b that are parallel to each other is provided. That is, the engaging portion 42 is also configured to have a two-surface width in which a pair of engaging surfaces 42b are provided on the outer peripheral surface of a cylindrical portion 42a coaxial with the screwed portion 35a. In addition, since the engaging part 42 is arrange | positioned inside the coil spring 32, the outer diameter dimension is made smaller than the outer diameter dimension of the engaging part 41. FIG. Similarly to the engaging portion 41, a fastening tool 43 such as a spanner can be engaged with the engaging portion 42 from the radial side of the screwed portion 35a. At this time, since the engaging portion 42 is disposed inside the coil spring 32, the tool 43 is inserted from the gap between the winding portions 32 a of the coil spring 32. Then, the connecting member 35 can be held in the rotation direction around the axis of the screwed portion 35a by the tool 43 engaged with the engaging portion 42 to prevent the rotation.

  Next, a procedure for attaching the vibration isolator 31 between the housing 12 and the base 21 will be described.

  First, one end in the longitudinal direction of the coil spring 32 is fixed to the base 21 with a tapping screw 33. Next, the other end of the coil spring 32 is screwed into the threaded portion 35 a of the connection member 35, and the connection member 35 is attached to the other end of the coil spring 32. At this time, the amount of screwing of the coil spring 32 into the screwed portion 35a is adjusted to be a preset specified value.

  Next, the housing 12 is disposed on the distal end side of the connection member 35, and the shaft portion 36 b of the bolt 36 protruding from the connection member 35 is inserted into the mounting hole 37 of the housing 12. A tool 43 is engaged with one of the engaging portions 41, 42 of the connecting member 35 from the radial direction of the screwed portion 35a, and the connecting member 35 is held by the tool 43 so as not to rotate about the axis. In this state, the nut 38 is screwed from the tip of the shaft portion 36b of the bolt 36 protruding from the mounting hole 37, and the nut 38 is tightened to the bolt 36 using a tool 43 such as a torque wrench, ratchet, or spanner. When the nut 38 is tightened, the connection member 35 is held by the tool 43 so that the connection member 35 does not rotate together with the nut 38.

  By such a procedure, the nut 38 can be fastened to the bolt 36 while the screwing amount of the coil spring 32 with respect to the screwing portion 35a of the connecting member 35 is maintained at a specified value, and the connecting member 35 can be fixed to the housing 12.

  As described above, in the present invention, the engaging portions 41 and 42 capable of engaging the tool 43 from the radial direction of the screw-in portion 35a are provided in the connecting member 35. By engaging the tool 43 from the radial direction side of the screw-in part 35a, the connection member 35 can be held in the rotation direction by the tool 43. Therefore, the nut 38 can be tightened by using the tool 43 such as a torque wrench while holding the connection member 35 so as not to rotate by the tool 43 engaged with the engaging portions 41 and 42. The attachment work of the vibration isolator 31 (coil spring 32) between 12 and the base 21 becomes easy. Since the tool 43 that holds the connecting member 35 in the rotational direction is configured to engage with the engaging portions 41 and 42 from the radial direction of the screw-in portion 35 a, the tool 43 engaged with the connecting member 35 is used for the connection member 35. A torque wrench that is configured to cover the nut 38 from the axial direction while preventing rotation can be used as the tool 43. Accordingly, the tightening torque of the nut 38 can be easily managed.

  Note that the tool 43 may be a hand tool held by hand or provided on an assembly jig or the like and automatically operated.

  Further, in the present invention, the connecting member 35 is provided with the engaging portions 41 and 42 on one side and the other side in the axial direction with respect to the screwed portion 35a, respectively. Even if the outer side is covered with the housing 12, the connecting member 35 can be held in the rotational direction by engaging the tool 43 with the other engaging portion. An anti-vibration device 31 provided in a portion where the radially outer side of one engaging portion 41 is covered by the housing 12, and an anti-vibration device 31 provided in a portion where the radially outer side of the engaging portion 41 is not covered by the housing 12, Moreover, since the same connection member 35 can be used, the versatility of the connection member 35 can be improved and the cost of the vibration isolator 31 and the chain saw 11 can be reduced.

  FIG. 8 is a cross-sectional view showing a modification of the engaging portion shown in FIG. 5 and showing a case where the engaging portion is constituted by a polygonal column. FIG. 9 is a cross-sectional view showing a modification of the engaging portion shown in FIG. 5, wherein the engaging portion is configured as a hole that opens in the radial direction.

  In the case shown in FIG. 5, the engaging portions 41, 42 provided on the connecting member 35 are configured to have a two-surface width in which a pair of parallel engaging surfaces 41b, 42b are provided on the outer peripheral surface of the cylindrical portions 41a, 42a. .

  On the other hand, in the modification shown in FIG. 8, the engaging part 41 provided in the connection member 35 is configured as a regular hexagonal column. Thus, the engaging portion 41 configured as a regular hexagonal column has three pairs of two-surface widths each composed of a pair of engaging surfaces 41b parallel to each other, and a tool such as a spanner is provided on one of these two surfaces. Can be engaged.

  On the other hand, in the modification shown in FIG. 9, the engaging portion 41 is configured to include a hole 44 that opens in the radial direction on the outer peripheral surface of the cylindrical portion 41a. In this case, as the tool 43, for example, a rod-shaped tool such as a hexagon wrench is used. By inserting the rod-shaped tool 43 from the radial direction into the hole 44 of the engaging portion 41, the tool 43 is engaged with the engaging portion 41, and the connecting member 35 is held in the rotational direction by the tool 43, The rotation can be prevented.

  It goes without saying that the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the scope of the invention.

  For example, in the above-described embodiment, the chainsaw 11 is illustrated as a portable work machine. However, the present invention is not limited to this, and the present invention may be applied to other portable work machines such as a hedge trimmer.

  Moreover, in the said embodiment, although the engine 13 is used as a drive source, you may make it use not only this but an electric motor as a drive source. The engine 13 is not limited to a two-cycle gasoline engine, and may be a four-cycle gasoline engine or an engine using fuel other than gasoline.

  Further, in the above embodiment, the attachment portion 32b of the coil spring 32 is fixed to the base 21, and the connection member 35 is fixed to the housing 12. However, the present invention is not limited to this, and the attachment portion 32b of the coil spring 32 is used. May be fixed to the housing 12 and the connecting member 35 may be fixed to the base 21.

  Furthermore, in the said embodiment, although the engaging parts 41 and 42 are comprised as a hole which opens in two faces width, a polygonal column, and radial direction, it is not restricted to this, A tool can engage from radial direction. As long as the connection member 35 can be held in the rotational direction by the engaged tool, other configurations may be used.

  Furthermore, in the said embodiment, although the 1st fastening member is comprised with the volt | bolt 36 and the nut 38, it is good also as a structure which screws a tapping screw into the connection member 35 not only this but the 1st fastening member. .

  Furthermore, in the said embodiment, although the volt | bolt 36 is embed | buried under the connection member 35, it is not restricted to this, You may make it integrally provide a male screw in the connection member 35 coaxially with this. Further, the nut 38 may be embedded in the connection member 35, and the shaft portion 36 b of the bolt 36 inserted through the attachment hole 37 of the housing 12 may be screwed to the nut 38.

11 Chainsaw (portable work machine)
12 Housing (first member)
13 Engine (drive source)
14 Side case 15 Guide bar 16 Saw chain (processing blade)
21 Base (second member)
22 Rear handle 23 Front handle 24 Hand guard 25 Throttle lever 26 Lock lever 31 Anti-vibration device 32 Coil spring 32a Winding portion 32b Mounting portion 33 Tapping screw (second fastening member)
34 mounting hole 35 connecting member 35a screwed portion 35b one end face 36 bolt (first fastening member)
36a Head portion 36b Shaft portion 37 Mounting hole 38 Nut (first fastening member)
41 engaging part 41a cylindrical part 41b engaging surface 42 engaging part 42a cylindrical part 42b engaging surface 43 tool 44 hole

Claims (7)

A portable work machine that processes an object to be processed by a processing blade driven by a driving source,
A first member to which the drive source is attached;
A second member provided with a handle to be gripped by an operator;
A connecting member that includes a spiral screw-in portion and is fixed to either the first member or the second member at one end in the axial direction by a first fastening member provided coaxially with the screw-in portion;
A coil spring having one end screwed into the screwed portion and attached to the connection member, and the other end fixed to either the first member or the second member by a second fastening member; ,
An engagement portion that can be engaged with a tool from the radial direction side of the screwed portion is provided in the connection member, and the connection member can be held in the rotation direction by the tool engaged with the engagement portion. Portable work machine.   The portable work machine according to claim 1, wherein the first fastening member includes a bolt and a nut.   The portable work machine according to claim 1, wherein the engaging portion is configured by a pair of engaging surfaces provided to face each other.   The portable work machine according to claim 1 or 2, wherein the engaging portion is formed of a polygonal column.   The portable work machine according to claim 1, wherein the engaging portion is configured as a hole that opens in a radial direction.   The portable work machine according to claim 1, wherein the engaging portion is provided on one side in the axial direction with respect to the screwed portion.   The portable work machine according to claim 1, wherein the engaging portion is provided on the other side in the axial direction with respect to the screwed portion.

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