chain saw

Abstract

The present application provides a kind of chain saw, with the saw chain tensioning mechanism of the resin-made adjustment dial damage can be prevented.It is with the chain saw (1) of saw chain tensioning mechanism (50), saw chain tensioning mechanism (50) has: the resin-made adjustment dial (60) that can rotate freely around the axis of left and right direction;Metal-made rotation transmission component (70) can rotate freely around the axis of left and right direction;Metal-made feed screw component (80) can rotate freely around the axis of front and back direction;And with the sliding component (90) linked with guide rod (20).Sliding component (90) is threadedly engaged with feed screw component (80).The first gear (65) of adjustment dial (60) is engaged with the second gear (71) of rotation transmission component (70), and the first bevel gear (72) of rotation transmission component (70) is engaged with the second bevel gear (82) of feed screw component (80).

Description

Technical Field

[0001] This invention relates to a chainsaw, comprising a chainsaw tensioning mechanism for adjusting the tension of the chainsaw chain. Background Technology

[0002] Chainsaws used for cutting trees, planks, etc., have a chain tensioning mechanism for adjusting the tension of the saw chain that surrounds the outer periphery of the guide bar.

[0003] As a chain tensioning mechanism, there exists a chain tensioning mechanism that has an adjustment dial provided on the outer surface of the chainsaw body and a feed screw component provided inside the chainsaw body, and the adjustment dial and the feed screw component are connected by a bevel gear mechanism (for example, see Patent Document 1).

[0004] In this saw chain tensioning mechanism, a sliding member is threadedly engaged with the feed screw assembly, and this sliding member is connected to a guide rod. Furthermore, if the adjusting dial is rotated, the guide rod and the sliding member move together along the extension direction along with the feed screw assembly, thereby changing the tension of the saw chain.

[0005] Existing technical documents

[0006] Patent Document 1: U.S. Patent No. 7,676,934. Summary of the Invention

[0007] The technical problem that the invention aims to solve

[0008] In the existing saw chain tensioning mechanism described above, the bevel gear of the resin adjusting dial meshes with the bevel gear of the metal feed screw component. In this structure, there is a problem that the teeth of the resin bevel gear are easily damaged by the teeth of the metal bevel gear.

[0009] The objective of this invention is to provide a chainsaw with a chainsaw tensioning mechanism that solves the above-mentioned problems, allows for easy adjustment of the chain tension, and prevents damage to the resin-made adjustment dial.

[0010] Technical solutions for solving technical problems

[0011] To address the aforementioned issues, the present invention is a chainsaw having a chainsaw body and a guide rod extending in a front-rear direction, the rear portion of which is connected to the chainsaw body. The chainsaw includes a chainsaw tensioning mechanism for adjusting the tension of the saw chain surrounding the outer periphery of the guide rod. The chainsaw tensioning mechanism includes: a resin-made adjusting dial rotatable freely about a left-right axis on the outer surface of the chainsaw body; a metal rotary transmission member rotatable freely about a left-right axis; a metal feed screw member rotatable freely about a front-rear axis inside the chainsaw body; and a sliding member connected to the guide rod. The sliding member is threadedly engaged with the feed screw member and moves in the front-rear direction as the feed screw member rotates. A first gear formed on the outer periphery of the adjusting dial meshes with a second gear formed on the outer periphery of the rotary transmission member, and a first bevel gear formed on the rotary transmission member meshes with a second bevel gear formed on the feed screw member.

[0012] In the chainsaw of the present invention, when the adjustment dial is rotated, its rotational force is transmitted to the feed screw component via the rotation transmission component, and the sliding component of the feed screw component is fed out along the extension direction of the guide rod. Moreover, together with the sliding component, the guide rod moves along the extension direction, thereby changing the tension of the saw chain.

[0013] In the chainsaw of the present invention, a first gear disposed on an adjustment dial and a second gear disposed on a rotation transmission member rotate about an axis extending in the left-right direction. When the two gears, which rotate about two axes in the same direction, are meshed, the module of the gear teeth can be increased to improve the strength of the teeth. Moreover, by increasing the strength of the first gear, damage to the resin-made first gear due to the metal second gear can be prevented.

[0014] Furthermore, the chainsaw of the present invention has the advantage that when the chain tensioning mechanism is activated, the outer periphery of the adjusting dial can be held, making it easy to apply rotational force. Moreover, since the amount of movement of the guide rod is large relative to the rotation of the adjusting dial, the guide rod can be reliably moved with less force.

[0015] Furthermore, in the chainsaw of the present invention, the adjustment dial rotates about an axis extending along the width direction (left-right direction) of the chainsaw body. Therefore, even if the outer diameter of the adjustment dial is increased, the width of the chainsaw body can be suppressed from increasing.

[0016] Furthermore, in the chainsaw of the present invention, since the adjusting dial is made of resin, even if the outer diameter of the adjusting dial is increased, the weight increase of the chain tensioning mechanism can be suppressed.

[0017] Invention Effects

[0018] In the chainsaw of the present invention, a gear mechanism is used to simplify the construction of the chain tensioning mechanism. By rotating the adjustment dial, the rotational force can be transmitted from the resin-made adjustment dial to the metal feed screw component to adjust the tension of the chainsaw. Attached Figure Description

[0019] Figure 1 This is a side view of a chainsaw according to an embodiment of the present invention.

[0020] Figure 2 This is a side view of the chain tensioning mechanism of the chainsaw according to an embodiment of the present invention, viewed from the inside.

[0021] Figure 3 This is an exploded perspective view of the chain tensioning mechanism of the chainsaw according to an embodiment of the present invention, viewed from the inside.

[0022] Figure 4 This is a side view of the guide rod and chain tensioning mechanism of the chainsaw according to the embodiments of the present invention, viewed from the inside.

[0023] Explanation of reference numerals in the attached figures

[0024] 1: Chainsaw; 10: Chainsaw body; 11: Cover; 20: Guide rod; 21: Slide groove; 25: Connecting hole; 30: Saw chain; 50: Saw chain tensioning mechanism; 60: Adjusting dial; 62: Cylindrical component; 64: Rib; 65: First gear; 66: Holding part; 70: Rotation transmission component; 71: Second gear; 72: First bevel gear; 80: Feed screw component; 81: Threaded groove; 82: Second bevel gear; 90: Sliding component; 91: Connecting pin. Detailed Implementation

[0025] Embodiments of the present invention will be described in detail with appropriate reference to the accompanying drawings.

[0026] like Figure 1 As shown, the chainsaw 1 of this embodiment includes: a chainsaw body 10; a guide rod 20 connected to the chainsaw body 10; and a chainsaw tensioning mechanism 50 for adjusting the tension of the saw chain 30 surrounding the outer periphery of the guide rod 20.

[0027] In this embodiment of the chainsaw 1, except for the structure of the chain tensioning mechanism 50, the structure is the same as that of conventionally known chainsaws. Therefore, detailed description of the overall structure of the chainsaw 1 is omitted.

[0028] In the following description, "front" refers to the front end of guide rod 20. Figure 1 (Right side).

[0029] The chainsaw body 10 has a drive device (not shown) for rotating the saw chain 30, and the drive device is housed in a cover 11.

[0030] Guide rod 20 is a plate-shaped component extending in the front-to-back direction. For example... Figure 4 As shown, a groove 21 extending in the front-to-back direction is formed through the rear of the guide rod 20. A bolt (not shown) inserted into this groove 21 is used to mount the chainsaw body 10 (see reference 10). Figure 1 Thus, the guide rod 20 is connected to the chainsaw body 10 in a manner that allows it to move relative to the chainsaw body 10 in the front-back direction.

[0031] The saw chain 30 is a ring-shaped cutting component that surrounds the outer periphery of the guide rod 20. The rear part of the saw chain 30 is wrapped around the sprocket of the drive device (not shown). Due to the driving force of the drive device, the saw chain 30 is driven to rotate along the outer periphery of the guide rod 20.

[0032] like Figure 2 As shown, the saw chain tensioning mechanism 50 includes: an adjusting dial 60; a rotation transmission component 70; a feed screw component 80; and a sliding component 90.

[0033] like Figure 1 As shown, the adjustment dial 60 is a cylindrical resin component mounted on the right side of the cover 11 of the chainsaw body 10.

[0034] Adjust the dial 60 so that it can rotate freely around the axis extending in the left-right direction (the width direction of the chainsaw body 10) and be stored on the right side of the cover 11.

[0035] like Figure 3 As shown, on the outer peripheral surface of the adjustment dial 60, the circumferentially extending edge 64 protrudes around the entire circumference.

[0036] On the outer peripheral surface of the adjustment dial 60, a first gear 65 is formed on the base end side (outer surface side of the cover 11) of the prism 64. The first gear 65 is a cylindrical spur gear with teeth formed on the outer peripheral surface of the cylindrical member 62.

[0037] In this structure, the ridge 64 located approximately at the center of the outer peripheral surface of the adjustment dial 60 is used to prevent chips and dust generated during the operation of the chainsaw 1 from entering the gear part inside the cover 11, thereby avoiding damage to the gear part.

[0038] In addition, the adjusting dial 60 and the first gear 65 are a single device, and the force of the adjusting dial 60 when rotating is directly used to rotate the first gear 65. This can prevent the operator from applying excessive force to the adjusting dial 60 when adjusting the tension of the saw chain 30, thereby preventing damage to the adjusting dial 60 or the first gear 65.

[0039] On the outer peripheral surface of the adjustment dial 60, a gripping portion 66 is formed at the front end of the rib 64. The gripping portion 66 is the part held by hand when rotating the adjustment dial 60. The outer peripheral surface of the gripping portion 66 is continuously formed with wavy unevenness, so that it is not easy to slip when the fingertip is placed on the outer peripheral surface of the gripping portion 66.

[0040] like Figure 2 As shown, the rotary transmission component 70 is a metal component installed on the left side of the cover 11 of the chainsaw body 10. The rotary transmission component 70 is located on the rear side of the adjustment dial 60.

[0041] The rotation transmission component 70 is inserted into the hole formed in the cover 11 and is housed on the inner surface of the cover 11 in a state in which it can rotate freely about an axis extending in the left and right direction.

[0042] The base end of the rotation transmission component 70 is disposed on the inner surface side of the cover 11 (see reference). Figure 3 The front end of the rotation transmission component 70 is disposed on the outer surface side of the cover 11.

[0043] like Figure 3 As shown, a second gear 71 is formed at the front end of the rotation transmission member 70. The second gear 71 is a spur gear with teeth formed on the outer peripheral surface of the front end of the rotation transmission member 70. A portion of the second gear 71 protrudes from the opening formed on the outer surface of the cover 11 toward the adjustment dial 60. Furthermore, the second gear 71 meshes with the first gear 65 of the adjustment dial 60 (see reference). Figure 1 ).

[0044] Thus, the first gear 65 and the second gear 71 are spur gears and are arranged side by side inside the cover 11. In this structure, since it is not easy to apply a large force other than the direction of rotation to the first gear 65 with its large outer diameter and the second gear 71 with its small outer diameter, damage to the first gear 65 and the second gear 71 can be prevented. In addition, by arranging the first gear 65 and the second gear 71 side by side inside the cover 11, it is not necessary to increase the width of the chainsaw body 10 in the left-right direction, and the chainsaw body 10 can be compactly constructed.

[0045] In the saw chain tensioning mechanism 50 of this embodiment, the maximum outer diameter of the first gear 65 is larger than the maximum outer diameter of the second gear 71. Furthermore, the gear ratio of the second gear 71 relative to the first gear 65 is set between 0.1 and 0.5. Additionally, the module of both the first gear 65 and the second gear 71 is set to 0.5 mm or more.

[0046] Increasing the maximum outer diameter of the first gear 65 allows for a larger module of its teeth, reducing damage to the resin-molded teeth. However, if the first gear 65 is too large relative to the second gear 71, the pitch and module of the second gear 71 will be insufficient to accommodate the first gear 65. On the other hand, setting the outer diameter of the first gear 65 relatively small reduces the load on both gears, but increases the rotational speed of the adjustment dial 60 when adjusting the tension of the saw chain 30, making operation of the adjustment dial 60 more cumbersome. Therefore, it is desirable to set the ratio of the maximum outer diameter of the first gear 65 to the maximum outer diameter of the second gear 71 to a range of 2:1 to 8:1. Furthermore, it is even more desirable to set the ratio of the maximum outer diameter of the first gear 65 to the maximum outer diameter of the second gear 71 to a range of 4:1 to 5:1.

[0047] In the saw chain tensioning mechanism 50 of this embodiment, the maximum outer diameter of the adjusting dial 60, which has the first gear 65, is significantly larger than the maximum outer diameter of the second gear 71.

[0048] In this structure, by increasing the outer diameter of the adjusting dial 60, the number of rotations of the adjusting dial 60 can be reduced when adjusting the tension of the saw chain 30, thus improving the operability of the adjusting dial 60.

[0049] In this embodiment, the ratio of the maximum outer diameter of the adjustment dial 60 to the maximum outer diameter of the second gear 71 is set to 4.5:1. In this structure, by forming a relatively large adjustment dial 60, the overall gear structure is not too large even when the first gear 65 and the second gear 71, which are spur gears, are arranged side by side in the front-rear direction, thus maintaining the operability of the adjustment dial 60 and allowing the chainsaw body 10 to be compactly constructed in the front-rear direction.

[0050] A first bevel gear 72 is formed at the base end of the rotation transmission member 70. The first bevel gear 72 gradually decreases in diameter as it approaches the base end of the rotation transmission member 70.

[0051] The feed screw assembly 80 is a metal component with a circular cross-section extending in the front-rear direction. The feed screw assembly 80 is connected to the inner surface of the left side of the cover 11 in a state where it can rotate freely about an axis extending in the front-rear direction (see reference). Figure 2 A helical thread groove 81 is formed on the outer peripheral surface of the feed screw component 80.

[0052] A second bevel gear 82 is formed at the rear end of the feed screw assembly 80. (Refer to...) Figure 2 and Figure 4 It is easy to understand that the diameter of the second bevel gear 82 gradually decreases as it moves toward the rear end.

[0053] The sliding component 90 is a metal nut that is threaded into the threaded groove 81 of the feed screw component 80 (see reference). Figure 3 ).

[0054] As the feed screw assembly 80 rotates, the sliding member 90 is extended in the front-to-back direction due to the threaded groove 81. Thus, the sliding member 90 moves in the front-to-back direction along with the rotation of the feed screw assembly 80.

[0055] A connecting pin 91 protruding into the inside of the chainsaw body 10 is formed in the sliding component 90.

[0056] like Figure 4 As shown, the connecting pin 91 is inserted into the connecting hole 25 formed at the rear of the guide rod 20. In this way, the sliding member 90 is connected to the rear of the guide rod 20.

[0057] Next, the saw chain tensioning mechanism 50 pairs using this embodiment will be tested. Figure 1 The method for adjusting the tension of the saw chain 30 shown will be explained.

[0058] If the adjusting dial 60 of the rotating saw chain tensioning mechanism 50 is rotated, its rotational force is transmitted from the first gear 65 of the adjusting dial 60 to... Figure 2 The second gear 71 of the rotary transmission component 70 shown rotates about an axis in the left-right direction.

[0059] In addition, rotational force is transmitted from the first bevel gear 72 of the rotation transmission component 70 to the second bevel gear 82 of the feed screw component 80, and the feed screw component 80 rotates about the axis in the front-back direction.

[0060] Furthermore, if the feed screw assembly 80 rotates, the sliding member 90 is pushed out in the front-to-back direction due to the threaded groove 81, and together with the sliding member 90, the guide rod 20 (see reference) Figure 4 It moves along the extension direction (front-back direction). As a result, the tension of the saw chain 30 changes.

[0061] like Figure 2 As shown, in the chainsaw 1 of this embodiment as described above, the first gear 65 provided in the adjusting dial 60 of the chain tensioning mechanism 50 and the second gear 71 provided in the rotation transmission member 70 rotate about an axis extending in the left-right direction.

[0062] Here, when two gears that rotate about two axes in the same direction are meshed, the module of the gear teeth can be increased to improve the strength of the teeth.

[0063] Therefore, in the saw chain tensioning mechanism 50 of this embodiment, by increasing the strength of the first gear 65, it is possible to prevent damage to the resin-made first gear 65 due to the metal second gear 71.

[0064] The saw chain tensioning mechanism 50 of this embodiment uses a gear mechanism to simplify the structure. Without the use of tools, the tension of the saw chain 30 can be easily adjusted by rotating the adjustment dial 60.

[0065] In the saw chain tensioning mechanism 50 of this embodiment, the gear ratio of the second gear 71 of the rotation transmission component 70 to the first gear 65 of the adjustment dial 60 is set between 0.1 and 0.5, and the maximum outer diameter of the first gear 65 is formed to be larger than the maximum outer diameter of the second gear 71.

[0066] Furthermore, the outer diameter of the adjusting dial 60 is also made relatively large to match the outer diameter of the first gear 65. In this way, if the outer diameter of the adjusting dial 60 is increased, it is easier to hold the adjusting dial 60 and apply rotational force. Moreover, the amount of movement of the guide rod 20 is greater relative to the amount of rotation of the adjusting dial 60, so the guide rod 20 can be moved with less force.

[0067] like Figure 1 As shown, in the saw chain tensioning mechanism 50 of this embodiment, the adjusting dial 60 rotates around the axis of the width direction (left-right direction) of the chainsaw body 10. Therefore, even if the outer diameter of the adjusting dial 60 is increased, the width of the chainsaw body 10 can be suppressed from increasing.

[0068] In addition, in the saw chain tensioning mechanism 50 of this embodiment, the adjusting dial 60 is made of resin. Therefore, even if the outer diameter of the adjusting dial 60 is increased, the weight increase of the saw chain tensioning mechanism 50 can be suppressed.

[0069] like Figure 3 As shown, in the chain tensioning mechanism 50 of this embodiment, a ridge 64 is formed on the outer peripheral surface of the adjusting dial 60, and a first gear 65 is formed at the portion near the base end of the ridge 64. In this structure, the ridge 64 can be used to prevent dust from entering the first gear 65 from the outside of the chainsaw body 10.

[0070] The embodiments of the present invention have been described above. However, the present invention is not limited to the above embodiments and can be appropriately modified without departing from its spirit.

[0071] like Figure 1 As shown, in the saw chain tensioning mechanism 50 of this embodiment, the first gear 65 of the adjusting dial 60 and the second gear 71 of the rotation transmission component 70 are spur gears. However, the type of gear is not limited if it is a gear that rotates about an axis extending in the left-right direction. For example, the first gear 65 and the second gear 71 can also be helical gears.

[0072] In the saw chain tensioning mechanism 50 of this embodiment, the gear ratio of the second gear 71 relative to the first gear 65 is set between 0.1 and 0.5, but the gear ratio is not limited.

[0073] In the saw chain tensioning mechanism 50 of this embodiment, the maximum outer diameter of the first gear 65 is formed to be larger than the maximum outer diameter of the second gear 71, but the size of the outer diameters of the first gear 65 and the second gear 71 is not limited.

Claims

1. A chainsaw comprising a chainsaw body and a guide rod extending in a front-rear direction, the rear portion of the guide rod being connected to the chainsaw body, characterized in that, The chainsaw includes a chainsaw tensioning mechanism for adjusting the tension of the saw chain surrounding the outer periphery of the guide bar. The saw chain tensioning mechanism includes: A resin adjustment dial that can rotate freely about a left-right axis on the outer surface of the chainsaw body. A metal rotary transmission component that can rotate freely around an axis in the left-right direction; A metal feed screw component that can rotate freely about a front-to-back axis inside the chainsaw body; and The sliding component connected to the guide rod, The sliding component is threadedly engaged with the feed screw component and moves in the back-and-forth direction as the feed screw component rotates. The first gear formed on the outer periphery of the adjusting dial meshes with the second gear formed on the outer periphery of the rotation transmission member, and The first bevel gear formed in the rotary transmission component meshes with the second bevel gear formed in the feed screw component; The first gear and the second gear are spur gears arranged side by side within the chainsaw body; The ratio of the maximum outer diameter of the first gear to the maximum outer diameter of the second gear is 2:1 to 8:1; A gripping portion is formed at the front end of the adjustment dial. The first gear is formed at the base end side of the adjustment dial. The ratio of the maximum outer diameter of the gripping part to the maximum outer diameter of the second gear is 4:1 to 5:

1.

2. The chainsaw according to claim 1, characterized in that, The gear ratio of the second gear relative to the first gear is set between 0.1 and 0.

5.

3. The chainsaw according to claim 1, characterized in that, The ratio of the maximum outer diameter of the first gear to the maximum outer diameter of the second gear is 4:1 to 5:

1.

4. The chainsaw according to any one of claims 1 to 3, characterized in that, The outer peripheral surface of the adjustment dial has a circumferentially extending ridge. The first gear is formed on the outer periphery of the adjustment dial at a position closer to the base end than the edge.

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