Saw chain

Abstract

To provide a technique capable of suppressing flapping of an object to be cut relative to a saw chain during cutting work, and suppressing accumulation of chips between the saw chain and the object to be cut during cutting work.SOLUTION: The saw chain comprises a plurality of drive links, a plurality of side links, and a plurality of connecting pins. At least some of the side links include a cutting section comprising a cutting blade and a depth gauge. A clam width of the saw chain is within a range of 4.3 mm to 4.6 mm. A depth of the saw chain is within a range of 0.1 mm to 0.3 mm. A chain pitch of the saw chain is within a range of 8.0 mm to 8.5 mm.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The technology disclosed in this specification relates to a saw chain. [Background technology]

[0002] Patent Document 1 discloses a saw chain movably attached to the periphery of a guide bar. The saw chain includes: a plurality of drive links, each having two drive link through-holes, aligned along a chain movement direction, i.e., the direction in which the saw chain moves relative to the guide bar; a plurality of side links, each having two side link through-holes, positioned on both the left and right sides of the drive links in a left-right direction, i.e., a direction perpendicular to the guide bar; and a plurality of connecting pins inserted through the drive link through-holes and the side link through-holes to connect each of the drive links to each of the side links. At least some of the side links include a cutting portion including a cutting blade and a depth gauge. In the left-right direction, the distance between the left end of the cutting blade, which is positioned on the left side of the drive links, and the right end of the cutting blade, which is positioned on the right side of the drive links, is within a range of 4.3 mm to 4.6 mm. In the chain height direction, which is a direction perpendicular to the left-right direction and the chain movement direction, the distance between the top of the cutting blade and the top of the depth gauge is within a range of 0.1 mm to 0.3 mm. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] U.S. Patent Application Publication No. 2011 / 0179652 Summary of the Invention [Problem to be solved by the invention]

[0004] For example, when using a saw chain to cut an object that is not firmly fixed in position (e.g., a small twig), the object may flap relative to the saw chain. Alternatively, when using a saw chain to cut a large object (e.g., a thick branch), chips may accumulate between the saw chain and the object. This specification provides a technology that can prevent the object from flapping relative to the saw chain during cutting work, while also preventing chips from accumulating between the saw chain and the object during cutting work. [Means for solving the problem]

[0005] The saw chain disclosed in this specification is a saw chain movably attached to the periphery of a guide bar. The saw chain includes: a plurality of drive links, each having two drive link through-holes, aligned along a chain movement direction, i.e., a direction in which the saw chain moves relative to the guide bar; a plurality of side links, each having two side link through-holes, positioned on both the left and right sides of the plurality of drive links in a left-right direction, i.e., a direction perpendicular to the guide bar; and a plurality of connecting pins inserted through the drive link through-holes and the side link through-holes to connect each of the plurality of drive links to each of the plurality of side links. At least some of the plurality of side links include a cutting portion including a cutting blade and a depth gauge. In the left-right direction, the distance between the left end of the cutting blade, which is positioned on the left side of the plurality of drive links, and the right end of the cutting blade, which is positioned on the right side of the plurality of drive links (also referred to as the "clip width" in this specification) is within a range of 4.3 mm to 4.6 mm. In the chain height direction, which is a direction perpendicular to the left-right direction and the chain movement direction, the distance between the top of the cutting blade and the top of the depth gauge (also referred to as "depth" in this specification) is within a range of 0.1 mm to 0.3 mm. The average value of the distance between the center axes of the two drive link through holes and the distance between the center axes of the two side link through holes (also referred to as "chain pitch" in this specification) is within a range of 8.0 mm to 8.5 mm.

[0006] According to the above configuration, the set width and depth are both small, thereby making the size of the cutting section compact. This prevents the object to be cut from flapping around the saw chain during cutting. Furthermore, according to the above configuration, the set width and depth are both small, thereby reducing the amount of material removed per cutting section (i.e., the amount of chips generated per cutting section). This prevents chips from accumulating between the saw chain and the object to be cut during cutting. Furthermore, according to the above configuration, the chain pitch is larger than, for example, the chain pitch (approximately 6.4 mm) of the saw chain of Patent Document 1. This results in a relatively large spacing between the side links in the direction of movement of the saw chain, which in turn results in a relatively large spacing between the cutting sections. As a result, chips are more easily discharged from between the saw chain and the object to be cut. This further prevents chips from accumulating between the saw chain and the object to be cut during cutting. Therefore, according to the above configuration, it is possible to prevent the object to be cut from flapping around the saw chain during cutting, while also preventing chips from accumulating between the saw chain and the object to be cut during cutting. [Brief explanation of the drawings]

[0007] [Figure 1] 1 is a diagram showing a state in which a saw chain 2 according to a first embodiment is attached to a chain saw body T1 via a guide bar 4. FIG. [Figure 2] 2 is a diagram showing the internal structure of a chainsaw body T1 according to the first embodiment. FIG. [Figure 3] 1 is a perspective view showing a part of a saw chain 2 according to a first embodiment. [Figure 4] 2 is a partial enlarged view of the saw chain 2 according to the first embodiment attached to the guide bar 4, as viewed from the right side. FIG. [Figure 5] 3 is a view of a cutting link 38R of the saw chain 2 according to the first embodiment as viewed from the right. FIG. [Figure 6]1 is a view of a part of a saw chain 2 according to a first embodiment, as viewed from the left-right direction and from a direction perpendicular to the chain movement direction. [Figure 7] 10 is a diagram showing a state in which a saw chain 2 according to a second embodiment is attached to a chainsaw body T2 via a guide bar 4. FIG. DETAILED DESCRIPTION OF THE INVENTION

[0008] Representative, non-limiting embodiments of the present invention are described in detail below with reference to the drawings. This detailed description is intended simply to provide those skilled in the art with details for implementing preferred embodiments of the present invention, and is not intended to limit the scope of the present invention. Furthermore, the additional features and inventions disclosed can be used separately or in conjunction with other features and inventions to provide further improved saw chains.

[0009] Furthermore, the combinations of features and steps disclosed in the following detailed description are not essential to practicing the invention in its broadest sense, but are described solely to specifically illustrate exemplary embodiments of the invention. Furthermore, the various features of the following exemplary embodiments and those described in the claims do not necessarily have to be combined in the exact embodiments described herein or in the exact order listed to provide additional and useful embodiments of the invention.

[0010] All features described in this specification and / or claims are intended to be disclosed individually and independently of one another as limitations to the specific features described in the original disclosure and claims, apart from the configuration of features described in the examples and / or claims. Furthermore, all numerical ranges and group or aggregate descriptions are intended to disclose intermediate configurations thereof as limitations to the specific features described in the original disclosure and claims.

[0011] In one or more embodiments, when the cutting portion is viewed along the left-right direction, the area of ​​the space enclosed by the line connecting the top of the cutting blade and the top of the depth gauge and the outer edge of the cutting portion (also referred to in this specification as the "notch area") is 10 mm 2 from 14mm 2 may be in the range of

[0012] According to the above configuration, the cutout area is small, which makes the size of the cutting portion more compact, thereby further reducing the flapping of the object to be cut relative to the saw chain during cutting work.

[0013] In one or more embodiments, for a side link having the cutting portion, the distance between the top of the cutting blade and the bottom of the side link in the chain height direction (also referred to herein as the "blade height") may be within a range of 8.0 mm to 10.0 mm.

[0014] As the blade height increases, the difference between the height (width in the chain height direction) of the side link with the cutting portion and the height of the side link without the cutting portion increases, and the gap between the saw chain and the object to be cut during cutting also increases. According to the above configuration, the blade height is set to a relatively large value, and therefore the gap between the saw chain and the object to be cut during cutting also increases to a certain extent. This makes it easier for chips to be expelled from between the saw chain and the object to be cut. This further reduces the accumulation of chips between the saw chain and the object to be cut during cutting.

[0015] In one or more embodiments, on both the left and right sides of the plurality of drive links, side links having the cutting portion (also referred to herein as "cutting links") and side links not having the cutting portion (also referred to herein as "tie straps") may be arranged alternately along the chain movement direction.

[0016] There are several types of saw chains with different arrangements of cutting links and tie straps. With the above configuration, the saw chain is a type with the highest ratio of cutting links to side links (a so-called full-cutter type). This increases the amount of cutting per movement of the saw chain (for example, one revolution around the guide bar), thereby improving work efficiency.

[0017] In one or more embodiments, the saw chain may be attached to a top-handle chainsaw body that includes a prime mover that drives the saw chain, a housing that supports the guide bar and the prime mover, and a top handle that is positioned vertically above the housing when the housing is placed on a horizontal surface.

[0018] There are three main types of chainsaw bodies: rear-handle, top-handle, and handheld. Rear-handle chainsaw bodies are also used for high-load work (e.g., felling trees). On the other hand, top-handle (or handheld) chainsaw bodies are mainly used for low-load work (e.g., cutting wood or pruning tree branches). For this reason, top-handle (or handheld) chainsaw bodies are expected to be used more often for cutting objects that are not firmly fixed in position (e.g., twigs) than rear-handle chainsaw bodies. With the above configuration, the saw chain is attached to the top-handle chainsaw body and used. That is, it is expected that the saw chain is often used for cutting objects that are not firmly fixed in position (e.g., twigs). An object that is not firmly fixed in position is likely to flap relative to the saw chain. Therefore, with the above configuration, the effect of suppressing flapping of the object to be cut relative to the saw chain during cutting work is significantly achieved.

[0019] In one or more embodiments, the saw chain may be attached to a handheld chainsaw body that includes a prime mover that drives the saw chain, a housing that supports the guide bar and the prime mover, and a grip that extends to protrude from the outer surface of the housing.

[0020] There are three main types of chainsaw bodies: rear-handle, top-handle, and handheld. Rear-handle chainsaw bodies are also used for high-load work (e.g., felling trees). On the other hand, handheld (or top-handle) chainsaw bodies are mainly used for low-load work (e.g., cutting wood and pruning tree branches). For this reason, handheld (or top-handle) chainsaw bodies are expected to be used more often for cutting objects that are not firmly fixed in position (e.g., twigs) than rear-handle chainsaw bodies. With the above configuration, the saw chain is attached to the handheld chainsaw body and used. That is, it is expected that the saw chain is often used for cutting objects that are not firmly fixed in position (e.g., twigs). An object that is not firmly fixed in position is likely to flap relative to the saw chain. Therefore, with the above configuration, the effect of suppressing flapping of the object to be cut relative to the saw chain during cutting work is significantly achieved.

[0021] In one or more embodiments, the saw chain may be attached to a chainsaw body having a weight in the range of 0.8 kg to 3.5 kg, the chainsaw body including a prime mover that drives the saw chain and a housing that supports the guide bar and the prime mover.

[0022] Typically, the heavier the chainsaw body, the more likely it is to be used for heavy-duty work (e.g., felling trees). Conversely, the lighter the chainsaw body, the more likely it is to be used for light-duty work (e.g., cutting wood or pruning tree branches). With the above configuration, the saw chain is attached to a relatively lightweight chainsaw body for use. For this reason, it is expected that the saw chain will often be used for cutting objects that are not firmly fixed in position (e.g., small twigs). Objects that are not firmly fixed in position are likely to flap relative to the saw chain. Therefore, with the above configuration, the effect of suppressing the flapping of the object to be cut relative to the saw chain during cutting work is significantly achieved.

[0023] Example 1 As shown in FIG. 1 , the saw chain 2 of this embodiment is attached to a handheld chainsaw body T1 for use. The chainsaw body T1 includes a housing 6 that supports a guide bar 4, a grip 8 that extends from the outer surface of the housing 6, a hand guard 10 that protects the user's hands when gripping the grip 8, and a chain cover 12 that covers a portion of the saw chain 2. A battery pack B1 is detachably attached to the tip of the grip 8. The battery pack B1 contains a rechargeable secondary battery, such as a lithium-ion battery. The chainsaw body T1 operates using power supplied from the battery pack B1. The grip 8 also includes a trigger lever 14. The trigger lever 14 is positioned so that it can be operated with the index finger of a user holding the grip 8. When the trigger lever 14 is operated, the chainsaw body T1 moves the saw chain 2 along the periphery of the guide bar 4.

[0024] As shown in FIG. 2 , the chainsaw body T1 further includes a sprocket 16 around which the saw chain 2 is wound from the guide bar 4, an electric motor 18 that drives the saw chain 2 via the sprocket 16, a control device 20 that controls the electric motor 18, a microswitch 22 that detects operation of the trigger lever 14, an oil tank 24 that stores lubricating oil for lubricating the saw chain 2, and an oil pump (not shown) that draws lubricating oil from the oil tank 24 and supplies it to the saw chain 2. The electric motor 18 in this embodiment is an inner-rotor DC brushless motor that includes a stator, a rotor disposed inside the stator, and an output shaft fixed to the rotor. The output shaft is connected to the sprocket 16 and the oil pump via a power transmission mechanism (e.g., a bevel gear) (not shown). The control device 20 activates the electric motor 18 when the trigger lever 14 is operated and the microswitch 22 is pressed. When the electric motor 18 operates, the sprocket 16 rotates, causing the saw chain 2 to move along the periphery of the guide bar 4. When the electric motor 18 operates, the oil pump is driven, and lubricating oil stored in the oil tank 24 is supplied to the saw chain 2.

[0025] The weight of the chainsaw body T1 is, for example, within a range of 0.8 kg to 2.2 kg, and is 1.2 kg in this embodiment. The weight of the chainsaw body T1 here is measured when the oil tank 24 is empty, the battery pack B1 is removed from the tip of the grip 8, and the saw chain 2 and guide bar 4 are removed from the housing 6.

[0026] In this embodiment, the longitudinal direction of the guide bar 4, that is, the direction from the housing 6 toward the guide bar 4, is defined as the forward direction, and the direction from the guide bar 4 toward the housing 6 is defined as the rearward direction. The direction perpendicular to the guide bar 4, that is, the direction from the oil tank 24 toward the guide bar 4, is defined as the leftward direction, and the direction from the guide bar 4 toward the oil tank 24 is defined as the rightward direction. The direction perpendicular to the front-rear and left-right directions, that is, the direction from the guide bar 4 toward the chain cover 12, is defined as the upward direction, and the direction from the chain cover 12 toward the guide bar 4 is defined as the downward direction.

[0027] The chainsaw body T1 moves the saw chain 2 in a predetermined direction along the periphery of the guide bar 4 at a speed of, for example, 8 m / s. In this embodiment, the direction in which the saw chain 2 moves relative to the guide bar 4 is defined as the chain movement direction M. The chain movement direction M is, for example, a counterclockwise direction when viewed from the left. In this embodiment, the direction perpendicular to the left-right direction (i.e., the direction perpendicular to the guide bar 4) and the chain movement direction M, and perpendicular to the direction away from the guide bar 4, is defined as the chain height direction H.

[0028] As shown in Figure 3, the saw chain 2 includes a plurality of drive links 32 arranged along the chain movement direction M, a plurality of side links 34 arranged on both the left and right sides of the plurality of drive links 32, and a plurality of connecting pins 36 connecting each of the plurality of drive links 32 and each of the plurality of side links 34 to each other.

[0029] The side links 34 are comprised of cutting links 38L, 38R and tie straps 40L, 40R. The cutting links 38L and tie straps 40L are arranged on the left side of the drive links 32. The cutting links 38R and tie straps 40R are arranged on the right side of the drive links 32. The cutting links 38L, 38R differ from the tie straps 40L, 40R in that they include cutting portions 42L, 42R. The cutting portions 42L, 42R include cutting blades 44L, 44R, depth gauges 46L, 46R arranged in the chain movement direction M as viewed from the cutting blades 44L, 44R, and notches 48L, 48R formed between the cutting blades 44L, 44R and the depth gauges 46L, 46R in the chain movement direction M.

[0030] As shown in FIG. 4, the guide bar 4 is provided on its periphery with a guide surface 52 that abuts against the bottom surface 50 of each of the side links 34 to support the saw chain 2, and a guide groove 54 recessed from the guide surface 52. A chain gauge 56 formed on each of the drive links 32 fits into the guide groove 54. The chain movement direction M can also be considered a tangential direction of the guide surface 52. In FIG. 4, the guide surface 52 of the guide bar 4 is illustrated as an approximation to a plane, and accordingly, the chain movement direction M is illustrated as an approximation to a straight line. Accordingly, in FIGS. 3, 5, and 6, the chain movement direction M is also illustrated as an approximation to a straight line.

[0031] Each of the multiple drive links 32 includes a first drive link through hole 62 and a second drive link through hole 64 disposed in the opposite direction of the chain movement direction M as viewed from the first drive link through hole 62. The first drive link through hole 62 and the second drive link through hole 64 are formed by penetrating the drive link 32 in the left-right direction. Each of the multiple side links 34 includes a first side link through hole 66 and a second side link through hole 68 disposed in the opposite direction of the chain movement direction M as viewed from the first side link through hole 66. The first side link through hole 66 and the second side link through hole 68 are formed by penetrating the side link 34 in the left-right direction. The first drive link through hole 62 of each of the multiple drive links 32 and the second side link through hole 68 of each of the multiple side links 34 are rotatably connected to each other via a connecting pin 36. The second drive link through-holes 64 of the drive links 32 and the first side link through-holes 66 of the side links 34 are rotatably connected to each other via the connecting pins 36 .

[0032] (About the chain pitch of Saw Chain 2) The average value (d1 + d2) / 2 of the distance d1 between the center axis of the first drive link through hole 62 and the center axis of the second drive link through hole 64 in each of the plurality of drive links 32 and the distance d2 between the center axis of the first side link through hole 66 and the center axis of the second side link through hole 68 in each of the plurality of side links 34 is also referred to as the "chain pitch." The chain pitch is, for example, within a range of 8.0 mm to 8.5 mm, and is 8.3 mm in this embodiment.

[0033] (About the blade height of Saw Chain 2) 5, the distance d3 from the bottom of the cutting link 38R (i.e., the bottom surface 50) to the top of the cutting blade 44R in the chain height direction H is also referred to as the "blade height." The blade height is, for example, within a range of 8.0 mm to 10.0 mm, and is 9.0 mm in this embodiment.

[0034] (About Saw Chainsaw 2 Depths) The distance d4 between the top of the cutting blade 44R and the top of the depth gauge 46R in the chain height direction H is also referred to as the “depth.” The depth is, for example, in the range of 0.1 mm to 0.3 mm, and is 0.25 mm in this embodiment.

[0035] (Regarding the cutout area of ​​Saw Chain 2) When the cutting portion 42R is viewed in the left-right direction, the area S of the space enclosed by the line V connecting the top of the cutting blade 44R and the top of the depth gauge 46R and the outer edge 42e of the cutting portion 42R is also called the "notch area." The notch area can also be said to be a value that represents the size of the notch portion 48R. The notch area is, for example, 10 mm 2 from 14mm 2 In this embodiment, the range is 12 mm. 2 is.

[0036] The cutting link 38R has a shape that is mirror-symmetrical to the cutting link 38L (see FIG. 4). Therefore, the dimensions d3 (blade height), d4 (depth), and S (notch area) described with reference to FIG. 5 also apply to the cutting link 38L.

[0037] (About the width of the chainsaw chain 2) 6, the distance d5 between the left end of the cutting blade 44L and the right end of the cutting blade 44R in the left-right direction is also called the "cavity width." The cavity width is, for example, in the range of 4.3 mm to 4.6 mm, and is 4.5 mm in this embodiment.

[0038] (Regarding the placement of cutting links 38L and 38R and tie straps 40L and 40R) As shown in Figure 3, the saw chain 2 is a so-called full cutter type saw chain in which cutting links 38L and tie straps 40L are arranged alternately along the chain movement direction M on the left side of the multiple drive links 32, and cutting links 38R and tie straps 40R are arranged alternately along the chain movement direction M on the right side of the multiple drive links 32.

[0039] Example 2 As shown in FIG. 7 , the saw chain 202 of this embodiment is attached to a top-handle type chainsaw body T2 for use. The chainsaw body T2 includes a housing 206 that supports the guide bar 204, a top handle 208, a side handle 210, hand guards 212 that protect the user's hands gripping the top handle 208 and / or the side handle 210, an oil tank 214 that stores lubricating oil for lubricating the saw chain 202, and an electric motor (not shown) that drives the saw chain 202. A battery pack B2 is detachably attached to the bottom of the housing 206. The battery pack B2 contains a rechargeable secondary battery, such as a lithium-ion battery. The chainsaw body T2 operates using power supplied from the battery pack B2.

[0040] When the chainsaw body T2 is placed on a horizontal surface P, the top handle 208 is disposed vertically above the housing 206. The top handle 208 is provided with a lock-off lever 216 and a trigger lever 218. When the lock-off lever 216 is not operated, operation of the trigger lever 218 is prohibited. When the lock-off lever 216 is operated, operation of the trigger lever 218 is permitted. Furthermore, when the chainsaw body T2 is placed on the horizontal surface P, the side handle 210 is disposed to the side of the housing 206. For example, a user holds the chainsaw body T2 by grasping the top handle 208 with their right hand and the side handle 210 with their left hand. From this state, when the user presses down the lock-off lever 216 of the top handle 208 with the palm of their right hand, operation of the trigger lever 218 is permitted. In this state, when the user pushes up the trigger lever 218 with the index finger of his right hand, the electric motor (not shown) operates with power supplied from the battery pack B2, and the saw chain 202 moves along the periphery of the guide bar 204. The chainsaw body T2 moves the saw chain 202 in a predetermined direction along the periphery of the guide bar 204 at a speed of, for example, 24 m / s.

[0041] The weight of the chainsaw body T2 is, for example, within a range of 2.0 kg to 3.5 kg, and is 2.5 kg in this embodiment. The weight of the chainsaw body T2 here is measured when the oil tank 214 is empty, the battery pack B2 is removed from the housing 206, and the saw chain 202 and guide bar 204 are removed from the housing 206.

[0042] The saw chain 202 corresponds to the saw chain 2 described in the first embodiment, except that the numbers of the interconnected drive links 32, the side links 34, and the connecting pins 36 are increased. Therefore, for a detailed description of the saw chain 202, please refer to the first embodiment.

[0043] (Variation) (See FIG. 5.) When the cutting portions 42L and 42R are viewed in the left-right direction, the area S (cutout area) of the space enclosed by the line V connecting the top of the cutting blades 44L and 44R to the top of the depth gauges 46L and 46R and the outer edge 42e of the cutting portions 42L and 42R is 10 mm 2 It can be smaller, 14mm 2 It may be larger.

[0044] (See FIG. 5) The distance d3 (blade height) from the bottom of the cutting link 38R to the top of the cutting blade 44R in the chain height direction H may be smaller than 8.0 mm or larger than 10.0 mm.

[0045] (See FIG. 3.) The saw chain 2, 202 may be a type of saw chain other than a full cutter type. For example, the saw chain 2, 202 may be a so-called standard type saw chain in which, with respect to combinations of side links 34 arranged in the left-right direction with a plurality of drive links 32 in between, the following combinations are repeatedly arranged along the chain movement direction M: a first combination consisting of a cutting link 38L and a tie strap 40R, a second combination consisting of a tie strap 40L and a tie strap 40R, a third combination consisting of a tie strap 40L and a cutting link 38R, and a fourth combination consisting of a tie strap 40L and a tie strap 40R.

[0046] The saw chain 2, 202 may be attached to a chainsaw body of a type other than a handheld type (or a top-handle type). For example, the saw chain 2, 202 may be attached to a so-called rear-handle type chainsaw body, in which the handle is located on the opposite side of the guide bar from the housing.

[0047] The saw chain 2, 202 may be attached to a chainsaw body weighing less than 0.8 kg, or alternatively, the saw chain 2, 202 may be attached to a chainsaw body weighing more than 3.5 kg.

[0048] (Features of the embodiment) In one or more embodiments, the saw chain 2 (or the saw chain 202) is a saw chain 2 (or the saw chain 202) that is movably attached to the periphery of the guide bar 4 (or the guide bar 204). The saw chain 2 (or the saw chain 202) includes: a plurality of drive links 32, each having two drive link through holes 62, 64, and aligned along a chain movement direction M, which is a direction in which the saw chain 2 (or the saw chain 202) moves relative to the guide bar 4 (or the guide bar 204); a plurality of side links 34, each having two side link through holes 66, 68, and arranged on both the left and right sides of the plurality of drive links 32 in the left-right direction, which is a direction perpendicular to the guide bar 4 (or the guide bar 204); and a plurality of connecting pins 36 that are inserted through the drive link through holes 62, 64 and the side link through holes 66, 68, thereby connecting each of the plurality of drive links 32 to each of the plurality of side links 34. Of the multiple side links 34, cutting links 38L, 38R (examples of at least some of the side links) have cutting portions 42L, 42R including cutting blades 44L, 44R and depth gauges 46L, 46R. In the left-right direction, a distance d5 (set width) between the left end of the cutting blade 44L located on the left side of the multiple drive links 32 and the right end of the cutting blade 44R located on the right side of the multiple drive links 32 is within a range of 4.3 mm to 4.6 mm. In the chain height direction H, which is a direction perpendicular to the left-right direction and the chain movement direction M, a distance d4 (depth) between the top of the cutting blade 44L, 44R and the top of the depth gauges 46L, 46R is within a range of 0.1 mm to 0.3 mm. The average value (d1 + d2) / 2 (chain pitch) of the distance d1 between the respective center axes of the two drive link through holes 62, 64 and the distance d2 between the respective center axes of the two side link through holes 66, 68 is within the range of 8.0 mm to 8.5 mm.

[0049] According to the above configuration, the set width and depth are small, thereby making the cutting portions 42L and 42R compact in size. This prevents the cutting object from flapping against the saw chain 2 (or the saw chain 202) during cutting. Furthermore, according to the above configuration, the set width and depth are small, thereby reducing the amount of cutting per cutting portion 42L and 42R (i.e., the amount of chips generated per cutting portion 42L and 42R). This prevents chips from accumulating between the saw chain 2 (or the saw chain 202) and the cutting object during cutting. Furthermore, according to the above configuration, the chain pitch is larger than, for example, the chain pitch (approximately 6.4 mm) of the saw chain of Patent Document 1. Therefore, the arrangement interval between the side links 34 in the movement direction of the saw chain 2 (or the saw chain 202) is relatively large, and therefore the arrangement interval between the cutting portions 42L and 42R is also relatively large. As a result, chips are more easily discharged from between the saw chain 2 (or the saw chain 202) and the cutting object. This further prevents chips from accumulating between the saw chain 2 (or saw chain 202) and the object to be cut during cutting work. Therefore, with the above configuration, it is possible to prevent the object to be cut from flapping relative to the saw chain 2 (or saw chain 202) during cutting work, while also preventing chips from accumulating between the saw chain 2 (or saw chain 202) and the object to be cut during cutting work.

[0050] In one or more embodiments, when the cutting portions 42L, 42R are viewed in the left-right direction, the area S (cutout area) of the space enclosed by the line V connecting the top of the cutting blades 44L, 44R and the top of the depth gauges 46L, 46R and the outer edge 42e of the cutting portions 42L, 42R is 10 mm 2 from 14mm 2 is within the range.

[0051] According to the above configuration, the cutout area is small, which makes the size of the cutting portions 42L, 42R even more compact. This further reduces the flapping of the object to be cut relative to the saw chain 2 (or the saw chain 202) during cutting work.

[0052] In one or more embodiments, for cutting links 38L, 38R (examples of side links with cutting portions), the distance d3 (blade height) between the top of the cutting blade 44L, 44R and the bottom of the side link 34 in the chain height direction H is within the range of 8.0 mm to 10.0 mm.

[0053] As the blade height increases, the difference between the heights of the cutting links 38L, 38R (width in the chain height direction H) and the height of the tie straps 40L, 40R (an example of a side link without a cutting portion) increases, and therefore the gap between the saw chain 2 (or the saw chain 202) and the object to be cut during cutting also increases. According to the above configuration, the blade height is set to a relatively large value, which increases the gap between the saw chain 2 (or the saw chain 202) and the object to be cut during cutting. This makes it easier for chips to be expelled from between the saw chain 2 (or the saw chain 202) and the object to be cut. This further reduces the accumulation of chips between the saw chain 2 (or the saw chain 202) and the object to be cut during cutting.

[0054] In one or more embodiments, the cutting links 38L, 38R and tie straps 40L, 40R are alternately arranged along the direction M of chain travel on both the left and right sides of the plurality of drive links 32.

[0055] There are multiple types of saw chains 2 (or saw chains 202) with respect to the arrangement of the cutting links 38L, 38R and tie straps 40L, 40R. According to the above configuration, the saw chain 2 (or saw chain 202) is a type (a so-called full cutter type) in which the ratio of cutting links 38L, 38R to the side link 34 is the highest. This increases the amount of cutting per movement of the saw chain 2 (or saw chain 202) (for example, one revolution around the guide bar 4 (or guide bar 204)), thereby improving work efficiency.

[0056] In one or more embodiments, the saw chain 202 is attached to a top-handle type chainsaw body T2 that includes an electric motor (an example of a prime mover) that drives the saw chain 202, a housing 206 that supports the guide bar 204 and the electric motor, and a top handle 208 that is positioned vertically above the housing 206 when the housing 206 is placed on a horizontal surface P.

[0057] There are three main types of chainsaw bodies: rear-handle type, top-handle type, and handheld type. Rear-handle type chainsaw bodies are also used for high-load work (e.g., felling trees). On the other hand, top-handle type chainsaw bodies are mainly used for low-load work (e.g., cutting wood and pruning tree branches). For this reason, top-handle type chainsaw bodies are expected to be used more often for cutting objects that are not firmly fixed in position (e.g., twigs) than rear-handle type chainsaw bodies. With the above configuration, the saw chain 202 is attached to the top-handle type chainsaw body T2 and used. That is, it is expected that the saw chain 202 is often used for cutting objects that are not firmly fixed in position (e.g., twigs). An object that is not firmly fixed in position is likely to flap around the saw chain 202. Therefore, with the above configuration, the effect of suppressing flapping of the object to be cut around the saw chain 202 during cutting work is significantly achieved.

[0058] In one or more embodiments, the saw chain 2 is attached to a handheld chainsaw body T1 that includes an electric motor 18 (an example of a prime mover) that drives the saw chain 2, a housing 6 that supports the guide bar 4 and the electric motor 18, and a grip 8 that extends to protrude from the outer surface of the housing 6.

[0059] There are three main types of chainsaw bodies: rear-handle type, top-handle type, and handheld type. Rear-handle type chainsaw bodies are also used for high-load work (e.g., felling trees). On the other hand, handheld type chainsaw bodies are mainly used for low-load work (e.g., cutting wood and pruning tree branches). For this reason, handheld type chainsaw bodies are expected to be used more often for cutting objects that are not firmly fixed in position (e.g., twigs) than rear-handle type chainsaw bodies. With the above configuration, the saw chain 2 is attached to the handheld type chainsaw body T1 and used. That is, the saw chain 2 is expected to be used more often for cutting objects that are not firmly fixed in position (e.g., twigs). An object that is not firmly fixed in position is likely to flap relative to the saw chain 2. Therefore, with the above configuration, the effect of suppressing flapping of the object to be cut relative to the saw chain 2 during cutting work is significantly achieved.

[0060] In one or more embodiments, the saw chain 2 (or saw chain 202) is attached to a chainsaw body T1 (or chainsaw body T2) having a weight in the range of 0.8 kg to 3.5 kg, the chainsaw body T1 (or chainsaw body T2) including an electric motor (an example of a prime mover) that drives the saw chain 2 (or saw chain 202) and a housing 6 (or housing 206) that supports the guide bar 4 (or guide bar 204) and the electric motor.

[0061] Typically, the heavier the chainsaw body, the more likely it is that it will be used for high-load work (e.g., felling trees). Conversely, the lighter the chainsaw body, the more likely it is that it will be used for low-load work (e.g., cutting wood or pruning tree branches). With the above configuration, the saw chain 2 (or the saw chain 202) is attached to the relatively lightweight chainsaw body T1 (or the chainsaw body T2) and used. For this reason, it is expected that the saw chain 2 (or the saw chain 202) will often be used to cut objects that are not firmly fixed in position (e.g., small twigs). Objects that are not firmly fixed in position are likely to flap around the saw chain 2 (or the saw chain 202). Therefore, with the above configuration, the effect of suppressing the flapping of the object to be cut around the saw chain 2 (or the saw chain 202) during cutting work is significantly achieved. [Explanation of symbols]

[0062] 2: Saw chain, 4: Guide bar, 6: Housing, 8: Grip, 10: Hand guard, 12: Chain cover, 14: Trigger lever, 16: Sprocket, 18: Electric motor, 20: Control device, 22: Microswitch, 24: Oil tank, 32: Drive link, 34: Side link, 36: Connecting pin, 38L: Cutting link, 38R: Cutting link, 40L: Tie strap, 40R: Tie strap, 42L: Cutting part, 42R: Cutting part, 42e: Outer edge of cutting part, 44L: Cutting blade, 44R: Cutting blade, 46L: Depth gauge, 46R: Depth gauge, 48L : Cutout portion, 48R: Cutout portion, 50: Bottom surface, 52: Guide surface, 54: Guide groove, 56: Chain gauge, 62: First drive link through-hole, 64: Second drive link through-hole, 66: First side link through-hole, 68: Second side link through-hole, 202: Saw chain, 204: Guide bar, 206: Housing, 208: Top handle, 210: Side handle, 212: Hand guard, 214: Oil tank, 216: Lock-off lever, 218: Trigger lever, B1: Battery pack, B2: Battery pack, T1: Chainsaw body, T2: Chainsaw body

Claims

1. A saw chain movably attached to the periphery of a guide bar, A plurality of drive links, each having two drive link through holes, arranged along a chain movement direction, which is a direction in which the saw chain moves relative to the guide bar; a plurality of side links, each having two side link through holes, disposed on both the left and right sides of the plurality of drive links in a left-right direction that is a direction perpendicular to the guide bar; a plurality of connecting pins that are inserted into the drive link through holes and the side link through holes to connect each of the plurality of drive links and each of the plurality of side links to each other, At least some of the side links among the plurality of side links include a cutting portion including a cutting blade and a depth gauge, a distance in the left-right direction between a left end of the cutting blade disposed on the left side of the plurality of drive links and a right end of the cutting blade disposed on the right side of the plurality of drive links is within a range of 4.3 mm to 4.6 mm; a distance between the top of the cutting blade and the top of the depth gauge in a chain height direction, which is a direction perpendicular to the left-right direction and the chain movement direction, is within a range of 0.1 mm to 0.3 mm; A saw chain, wherein the average value of the distance between the center axes of the two drive link through holes and the distance between the center axes of the two side link through holes is within the range of 8.0 mm to 8.5 mm.

2. When the cutting portion is viewed in the left-right direction, the area of ​​the space surrounded by the line connecting the top of the cutting blade and the top of the depth gauge and the outer edge of the cutting portion is 10 mm ２ From 14mm ２ The saw chain of claim 1, wherein the range is

3. A saw chain according to claim 1 or 2, wherein for a side link having the cutting portion, the distance between the top of the cutting blade and the bottom of the side link in the chain height direction is within the range of 8.0 mm to 10.0 mm.

4. A saw chain according to any one of claims 1 to 3, wherein side links having the cutting portion and side links not having the cutting portion are arranged alternately along the chain movement direction on both the left and right sides of the plurality of drive links.

5. A saw chain according to any one of claims 1 to 4, which is attached to a top-handle type chainsaw body comprising a prime mover that drives the saw chain, a housing that supports the guide bar and the prime mover, and a top handle that is positioned vertically above the housing when the housing is placed on a horizontal surface.

6. A saw chain according to any one of claims 1 to 4, which is attached to a handheld chainsaw body comprising a prime mover that drives the saw chain, a housing that supports the guide bar and the prime mover, and a grip that extends to protrude from the outer surface of the housing.

7. A saw chain according to any one of claims 1 to 4, which is attached to a chainsaw body comprising a prime mover that drives the saw chain and a housing that supports the guide bar and the prime mover, and which has a weight in the range of 0.8 kg to 3.5 kg.

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