JP2014104560A - Engine tool - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an engine tool whose cutting accuracy and sharpness can be improved and which has excellent operability, startability and vibration proof property and can be used easily.SOLUTION: An engine tool 1 comprises: a body housing 3 having a work cutting part 2; an operation handle 4 attached to the body housing 3; an engine 6 disposed on the body housing 3 through a first vibration proof member 5; and a shaft part 7 for transmitting power of the engine 6 toward the work cutting part 2. The shaft part 7 is formed of at least two shaft members including a crank shaft 8 of the engine 6 and a clutch shaft 9 disposed on the body housing 3, and the shaft members are coupled each other through a vibration proof engagement part 11 engaging through a second vibration proof member 10.

Description

  The present invention relates to an engine tool such as a chain saw, and more particularly to a technique for suppressing vibration transmitted from an engine to an operation handle.

  Engine tools such as chainsaws and hedge trimmers are used as working machines for cutting trees and pruning hedges in agriculture and forestry and gardening.

  Conventionally, in these engine tools, in order to make it difficult for vibration generated during work to be transmitted to an operator's hand, a technique for suppressing vibration using an elastic member such as vibration-proof rubber has been employed (Patent Document 1). reference).

  In the engine tool disclosed in Patent Document 1, at least three or more anti-vibration rubbers whose axes in the compression direction are perpendicular to each other are disposed between the engine and the main body housing that houses the engine and the operation handle. By making the spring constant of these anti-vibration rubbers uniform in the three-axis direction, vibration is reduced.

JP 2011-177798 A

  However, in the conventional engine tool as described above, vibration transmitted from the main body housing to the operation handle can be suppressed. However, since an elastic member having a low elastic coefficient is used as a vibration-proof structure, the elastic member There is a problem that the operation handle connected to the main body housing is likely to wobble, and the operation when starting the engine is likely to be unstable.

  Moreover, since the working blade part attached to the main body housing vibrates integrally with the engine, there is a problem that the cutting edge is likely to be shaken, resulting in a decrease in cutting accuracy and sharpness.

  The engine tool described in Patent Document 1 is provided with a vibration-proof structure between the engine and the main body housing, so that it is possible to suppress the vibration of the cutting edge of the working blade due to the vibration of the engine, The engine will move relative to the body housing. For this reason, for example, in a chain saw, when the drive sprocket is pulled toward the guide bar when the saw chain is stretched, the engine is pulled together, and there is a problem that the drive sprocket is tilted or the tension of the saw chain is not stable. .

  Furthermore, there has been a problem that engine vibration is transmitted from the crankshaft to the operation handle via the drive sprocket, saw chain, guide bar, and main body housing.

  Accordingly, the present invention has been made to solve the above-described problems, and provides an easy-to-use engine tool that is excellent in operability, startability and vibration proofing as well as improving cutting accuracy and sharpness. It is an object.

  The present invention provides a main body housing having a working blade portion, an operation handle attached to the main body housing, an engine provided in the main body housing via a first vibration isolating member, and the power of the engine as the work An engine tool including a shaft portion for transmitting to a blade portion, wherein the shaft portion includes at least two shaft members including a crankshaft of the engine and a clutch shaft provided in the main body housing. These shaft members are connected to each other via a vibration isolating engaging portion that engages with each other with a second vibration isolating member interposed therebetween.

  The main body housing is preferably provided with a bearing member that supports the clutch shaft.

  The clutch shaft is preferably provided with a rotation output portion via a centrifugal clutch.

  The anti-vibration engaging portion is provided on the one shaft member and the other shaft member facing each other on the axis, the first convex portion and the first concave portion provided on the one shaft member, and the other shaft member. A second concave portion that engages with the first convex portion, a second convex portion that engages with the first concave portion, and between the first convex portion and the second concave portion, It is preferable that a second vibration isolating member interposed between the first concave portion and the second convex portion is provided.

  The anti-vibration engagement portion is loosely fitted to the inner periphery of one of the crank shaft and the clutch shaft, and the outer periphery of the other shaft member is loosely fitted to the inner periphery of the one shaft member. A plurality of concave portions are provided at equal intervals, and a plurality of convex portions are provided on the outer periphery of the other shaft member with a predetermined gap in the concave portion, and the second portion is provided in the gap between the concave portions and the convex portions. It is preferable that an anti-vibration member is interposed.

  The anti-vibration engaging portion includes a first concave portion and a first convex portion that are provided adjacent to each other in the axial direction on a side portion of one of the crank shaft and the clutch shaft, and the other shaft. A second convex portion provided adjacent to the side portion of the member in the axial direction, and engaged with the first concave portion via the first gap; and a second gap in the first convex portion. It is preferable to include a second concave portion to be engaged and the second vibration isolation member provided in the first gap and the second gap.

  According to the present invention, it is possible to provide a user-friendly engine tool that can improve cutting accuracy and sharpness, and can improve operability and startability.

It is a side view which shows the principal part of the chainsaw which is the 1st Embodiment of this invention. It is an AA line expanded sectional view of FIG. FIG. 3 is an enlarged sectional view taken along line B-B in FIG. 2. It is a figure which shows the modification of a vibration proof engagement part. It is a figure which shows the other example of a vibration proof engagement part. It is sectional drawing which shows the principal part of the hedge trimmer which is the 2nd Embodiment of this invention.

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

  As shown in FIGS. 1 and 2, a chain saw 1 as an example of an engine tool includes a main body housing 3 having an endless saw chain 2 as a working blade portion, an operation handle 4 attached to the main body housing 3, and The main body housing 3 includes an engine 6 provided via a first vibration isolation member 5 and a shaft portion 7 for transmitting the power of the engine 6 to the saw chain 2. The shaft portion 7 is composed of at least two or more shaft members including a crank shaft 8 of the engine 6 and a clutch shaft 9 provided in the main body housing 3. They are connected to each other via a vibration isolating engaging portion 11 that engages with the second vibration isolating member 10 therebetween.

  The main body housing 3 includes a base portion 12 and side covers 15 attached to the base portion 12 via bolts 13 and nuts 14 serving as fastening means. The base portion 12 constitutes one side wall of the main body housing 3. The side cover 15 includes a guide bar holding portion 15 a that holds the guide bar 16 with the base portion 12, and a clutch housing portion 15 b that houses a clutch such as the centrifugal clutch 17 and the drive sprocket 18. The base portion 12 includes a guide bar holding portion 12a that holds the guide bar 16 between the base bar 12 and the guide bar holding portion 15a of the side cover 15, and a cover portion 12b that covers the open end of the clutch housing portion 15b of the side cover 15. doing.

  A base end portion of the guide bar 16 is sandwiched between a guide bar holding portion 12a of the base portion 12 and a guide bar holding portion 15a of the side cover 15 via a metal plate (not shown). The guide bar holding portion 15a of the base portion 12 is provided with a bolt 13 and a position restricting pin 19 protruding in parallel with each other with a gap in the longitudinal direction of the guide bar 16, and a base end portion of the guide bar 16 A long hole 20 for position adjustment that engages with the bolt 13 and the position regulating pin 19 is formed along the longitudinal direction of the guide bar 16.

  The guide bar holding portion 15a of the side cover 15 is provided with fitting holes 21 and 22 into which the tip of the bolt 13 and the tip of the position restricting pin 19 are fitted, respectively. By screwing and tightening the nut 14 to the bolt 13, the side cover 15 is fixed to the base portion 12 and the guide bar 16 is fixed. The base portion 12 is screwed with a peripheral edge of the side cover 15 on the clutch housing portion 15b side (not shown).

  The clutch shaft 9 is provided with a clutch shoe 23 that opens in the radial direction by centrifugal force, and a receiving clutch outer 24 on the outer periphery thereof. The clutch outer 24 is rotatably provided on the clutch shaft 9 via a bearing 25. The clutch outer 24 is provided with a drive sprocket 18 for winding the saw chain 2. One end of the clutch shaft 9 is supported on the inner surface of the side cover 15 via a bearing 26, and the other end of the clutch shaft 9 penetrates the base portion 12 and is supported on the outer surface of the base portion 12 via a bearing 27. The clutch shaft 9 is divided into a first shaft 9a on the clutch shoe 23 side and a second shaft 9b on the clutch outer 24 side, and a male screw portion 30 provided on the second shaft 9b is provided on the first shaft 9a. The first shaft 9a and the second shaft 9b are integrated by screwing into the female screw hole 31.

  The saw chain 2 is wound between the drive sprocket 18 and the guide bar 16, and a rotational force is applied to the saw chain 2 via the drive sprocket 18 by the power of the engine 6.

  The operation handle 4 includes an upper handle 4a and a side handle 4b. The upper handle 4a is provided with a throttle lever 32 and a release lever 33 for releasing the lock of the throttle lever 32 locked at the idling position. The side handle 4b is attached across the upper handle 4a and the base portion 12.

  The engine 6 includes an engine cover 34 having a cylinder (not shown), a crankshaft 8 that is rotatably provided in the engine cover 34 via a bearing 35, and a crank portion 36 of the crankshaft 8 via a piston rod 37. And a piston (not shown) that is connected and reciprocates in the cylinder. Further, the engine 6 is provided with a fuel tank, a generator, a spark plug, and a manual starter 38.

  The engine 6 is attached to the base portion 12 of the main body housing 3 via the first vibration isolation member 5. The first vibration isolating member 5 is made of a bottomed cylindrical rubber body, and an annular groove 39 on the outer periphery thereof is fitted into the flange portion 40 of the mounting hole of the base portion 12, and the first vibration isolating member 5 Is fixed to an attachment portion 42 formed on the side surface of the engine cover 34 via attachment screws 43.

  The shaft portion 7 includes at least two shaft members including a crankshaft 8 of the engine 6 and a clutch shaft 9 provided in the main body housing 3, and these shaft members (the crankshaft 8 and the clutch shaft 9). Are connected via an anti-vibration engaging portion 11 engaged with each other with the second anti-vibration member 10 interposed therebetween.

  As shown in FIGS. 2 to 3, the anti-vibration engaging portion 11 is provided on the crankshaft 8, and the crankshaft 8 that is one shaft member that is opposed on the axis and the clutch shaft 9 that is the other shaft member. The first convex portion 45a and the first concave portion 45b, the second concave portion 46b that is provided on the clutch shaft 9 and engages with the first convex portion 45a, and the second convex portion that engages with the first concave portion 45b. Part 46a, and second vibration isolator member 10 interposed between first concave part 45b and second convex part 46a, respectively, between first convex part 45a and second concave part 46b. .

  The anti-vibration engaging portion 11 is configured such that the outer periphery of the other shaft member, for example, the crankshaft 8 is loosely fitted to the inner periphery of one of the crankshaft 8 and the clutch shaft 9, for example, the clutch shaft 9. Are provided with a plurality of (four in the illustrated example) first recesses 46b at equal intervals in the circumferential direction, and the outer periphery of the crankshaft 8 is engaged with the second recesses 46b with a predetermined gap S therebetween. A plurality of (four in the illustrated example) first convex portions 45a are provided, and the second vibration isolating member 10 is interposed in the gap S between the second concave portions 46b and the first convex portions 45a. .

  A shaft end portion on the engine side of the clutch shaft 9 has a boss portion 46 having a diameter larger than the diameter of the clutch shaft 9. When four second recesses 46b are formed on the inner periphery of the boss portion 46, first, a central recess (not shown) having an inner diameter slightly larger than the outer diameter of the end portion of the crankshaft 8 is formed on the boss portion 46. In addition, lateral second concave portions 46b extending radially in four directions at equal intervals in the circumferential direction are provided on the inner periphery of the central concave portion. The flat surface portion 10a of the second vibration isolating member 10 is disposed on the concave flat surface portion including the central concave portion and the lateral second concave portion 46b, and the first concave portion 46b on the side of the boss portion 46 and the crankshaft. The side surface part 10b which is the peripheral part of the 2nd vibration isolator 10 is arrange | positioned in the clearance gap S between 8 1st convex parts 45a.

  The second vibration isolating member 10 is made of an elastic member such as rubber. The second vibration isolation member 10 has a flat surface portion 10a and a side surface portion 10b integrally formed of a rubber material having a predetermined thickness, and the crankshaft 8 and the clutch shaft 9 are connected to each other via the second vibration isolation member 10. They are joined together.

  In the chain saw 1 having the above-described configuration, the engine 6 is started by holding one of the operation handles 4 with one hand and pulling the starter 38 with the other hand. By pulling the throttle lever 32 provided on the handle 4a, the idle speed can be adjusted to the full speed state. When the rotation speed reaches a certain value, the saw chain 2 wound around the outer periphery of the guide bar 16 is driven, and the tree Etc. can be cut.

  When the engine 6 is driven, vibration of the engine 6 is transmitted from the main body housing 3 to the guide bar 16 and from the main body housing 3 to the operation handle 4. Since the operator holds the operation handle 4 when operating the chainsaw 1, it is desirable that vibration of the engine 6 is not transmitted to the operation handle 4 as much as possible.

  Therefore, according to the chain saw 1 of the present embodiment, the main body housing 3 having the saw chain 2, the operation handle 4 attached to the main body housing 3, and the main body housing 3 through the first vibration isolation member 5 are provided. And a shaft portion 7 for transmitting the power of the engine 6 to the working blade portion 2, and the shaft portion 7 includes a crankshaft 8 of the engine 6 and a clutch shaft 9 provided in the main body housing 3. From the engine 6, the shaft members are connected via a vibration isolating engagement portion 11 that engages with each other with the second vibration isolating member 10 interposed therebetween. Vibration transmitted to the main body housing 3 can be reduced or absorbed.

  The main body housing 3 is provided with at least one (two in the embodiment) bearings (bearing members) 26 and 27 for supporting the clutch shaft 9, and the clutch shaft 9 is supported by these bearings 26 and 27. Therefore, the position of the drive sprocket 18 is not affected by the force received from the outside, and the inclination of the drive sprocket 18 can be suppressed. Therefore, it is possible to provide a user-friendly chain saw 1 that can improve cutting accuracy and sharpness, and can improve operability and startability. Even if the hardness of the vibration isolator connected to the engine 6 is set low, the operation handle 4 and the main body housing 3 are connected directly or with a high vibration isolator so that the operation handle 4 follows. It can be operated with good performance.

  Since the clutch shaft 9 is provided with a drive sprocket 18 which is a rotation output unit via a centrifugal clutch 17, power can be output in a stable state.

  The anti-vibration engaging portion 11 includes a crankshaft 8 that is one shaft member facing on the axis, a clutch shaft 9 that is the other shaft member, a first convex portion 45a provided on the crankshaft 8, and A first recess 45b, a second recess 46b that is provided on the clutch shaft 9 and engages with the first protrusion 45a, a second protrusion 46a that engages with the first recess 45b, and a first Since the second vibration isolating member 10 interposed between the first convex portion 45a and the second concave portion 46b and between the first concave portion 45b and the second convex portion 46a is provided, the crankshaft 8 The power can be transmitted while suppressing the vibration of the engine 6 transmitted to the clutch shaft 9.

  Further, the anti-vibration engaging portion 11 is loosely fitted to the outer periphery of one of the crankshaft 8 and the clutch shaft 9 such as the crankshaft 8, and the other shaft member such as the clutch shaft 9 is loosely fitted. 8 is provided with first convex portions 45a and first concave portions 45b at equal intervals in the circumferential direction, and a predetermined gap S exists in the first convex portion 45a on the inner periphery of the clutch shaft 9. A second concave portion 46b to be engaged and a second convex portion 46a to be engaged with the first concave portion 45b with a predetermined gap S are provided, and between the concave portions 45b and 46b and the convex portions 45a and 46a. Since the second vibration isolation member 10 is interposed in the gap S, the vibration of the engine 6 transmitted from the crankshaft 8 to the clutch shaft 9 can be absorbed by the second vibration isolation member 10. Effective swing and vibration of saw chain and operation handle It can be suppressed.

  As mentioned above, although one embodiment of the engine tool concerning the present invention was described, the present invention is not limited to the above-mentioned embodiment, and it is various in the range which does not deviate from the spirit of the invention indicated in the claim. Variations and improvements are possible.

  For example, in the above-described embodiment, the fitting portion of the crankshaft and the clutch shaft is formed as a so-called four crotch where four recesses and four recesses engage via a gap, but as shown in FIG. Two recesses and three recesses may be formed in a so-called three crotch where they are engaged through a gap, or may be formed in five or more crotch. In addition, about the detailed description of the modification of the vibration proof engagement part of FIG. 4, the same code | symbol as FIG. 3 is attached | subjected and abbreviate | omitted.

  Moreover, although the example applied to the top handle type engine chain saw is shown in the embodiment, the present invention can be applied to a rear handle type engine chain saw and an engine hedge trimmer.

  Further, the structure of the crankshaft 8 of the shaft portion 7 and the anti-vibration engaging portion 11 of the clutch shaft 9 is as shown in FIG. The first concave portion 47a and the first convex portion 47b provided adjacent to each other in the axial direction and the side portion of the other clutch shaft 9 material are provided adjacent to each other in the axial direction, and the first concave portion 47a includes the first concave portion 47a. The second protrusion 48b and the second protrusion 48b that engage with the first protrusion 47b with the second gap S2 therebetween, and the first gap S1 and the first protrusion Sb. The second vibration isolating member 10 provided in the two gaps S <b> 2 may be provided.

  FIG. 6 shows an embodiment in which the present invention is applied to an engine hedge trimmer, and the structure of the vibration isolating structure is the same as that of the engine chain saw of the above embodiment. That is, the hedge trimmer 50 includes a main body housing 53 having a working blade, an operation handle (not shown) attached to the main body housing 53, and an engine 6 provided on the main body housing 3 via the first vibration isolation member 5. And a shaft portion 7 for transmitting the power of the engine 6 to the working blade portion 2. The shaft portion 7 includes at least two shaft members including a crankshaft 8 of the engine 6 and a clutch shaft 9 provided in the main body housing 53. The crankshaft 8 and the clutch shaft 9 are second to each other. Are connected via a vibration isolating engaging portion 11 that is engaged with the vibration isolating member 10 therebetween.

  The clutch shaft 9 is divided into a first shaft 9a on the clutch shoe 23 side and a second shaft 9b on the clutch outer 24 side, and the first shaft 9a and the second shaft 9b are respectively connected to the body housing via bearings 26 and 27. Since it is supported by 53 and is regulated in position, it is possible to prevent contact between the clutch shoe 23 and the clutch outer 24 due to rattling. A lower part of the main body housing 53 is provided with a fixed blade blade 54 extending horizontally forward and having a plurality of blades on both sides, and a movable blade blade 55 extending horizontally forward and having a plurality of blades on both sides. It has been. A pinion 56 is provided on the second shaft 9 b, and a gear 58 having an eccentric cam 57 for reciprocating the movable blade blade 55 back and forth by driving the pinion 56 is attached to the fixed blade blade 54.

  The engine hedge trimmer 50 provides an easy-to-use engine hedge trimmer that can improve cutting accuracy and sharpness, and is excellent in operability, startability, and vibration proofing, similar to the chain saw of the embodiment of FIG. be able to.

1 Chain saw (engine tool)
2 Saw chain (work blade)
DESCRIPTION OF SYMBOLS 3 Main body housing 4 Operation handle 5 1st anti-vibration member 6 Engine 7 Shaft part 8 Crankshaft 9 Clutch shaft 10 Second anti-vibration member 11 Anti-vibration engagement part 18 Drive sprocket (rotation output part)
45a 1st convex part 45b 1st recessed part 46a 2nd convex part 46b 2nd recessed part

Claims (6)

  A main body housing having a working blade portion, an operation handle attached to the main body housing, an engine provided in the main body housing via a first vibration isolation member, and transmitting the power of the engine to the working blade portion An engine tool including a shaft portion for performing, wherein the shaft portion includes at least two shaft members including a crankshaft of the engine and a clutch shaft provided in the main body housing, An engine tool characterized in that these shaft members are connected to each other via a vibration isolating engaging portion that engages with each other with a second vibration isolating member interposed therebetween.   The engine tool according to claim 1, wherein the main body housing is provided with a bearing member that supports the clutch shaft.   The engine tool according to claim 1 or 2, wherein a rotation output portion is provided on the clutch shaft via a centrifugal clutch.   The anti-vibration engaging portion is provided on the one shaft member and the other shaft member facing each other on the axis, the first convex portion and the first concave portion provided on the one shaft member, and the other shaft member. A second concave portion that engages with the first convex portion, a second convex portion that engages with the first concave portion, and between the first convex portion and the second concave portion, The engine tool according to any one of claims 1 to 3, further comprising a second vibration isolation member interposed between the first concave portion and the second convex portion.   The anti-vibration engaging portion is such that the outer periphery of one of the crank shaft and the clutch shaft is loosely fitted to the inner periphery of the other shaft member, and the outer periphery of the one shaft member is circumferentially or the like. A first convex portion and a first concave portion are provided at an interval, and a second concave portion that engages with the first convex portion via a predetermined gap on the inner periphery of the other shaft member, and the first A second convex portion is provided to be engaged with the concave portion with a predetermined gap, and the second vibration isolating member is interposed in the gap between the concave portion and the convex portion. Item 5. The engine tool according to Item 4.   The anti-vibration engaging portion includes a first concave portion and a first convex portion that are provided adjacent to each other in the axial direction on a side portion of one of the crank shaft and the clutch shaft, and the other shaft. A second convex portion provided adjacent to the side portion of the member in the axial direction, and engaged with the first concave portion via the first gap; and a second gap in the first convex portion. 5. The engine tool according to claim 4, further comprising a second recessed portion to be engaged, and the second vibration isolation member provided in the first gap and the second gap.

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