Cutting tool

Abstract

This invention relates to a cutting tool, and this specification provides a technique for preventing a loosening inhibition member from detaching from a threaded member. The cutting tool disclosed in this specification includes: a first cutter; a second cutter rotatable relative to the first cutter; a base member supporting the first and second cutters; a threaded member comprising a head and a shaft extending from the head as a base end and having external threads, wherein the first cutter and the base member are fastened together by threading the external threads with internal threads; a loosening inhibition member mounted on the shaft portion, which is pressed by the head to prevent loosening of the threaded member; and a detachment inhibition member mounted adjacent to the loosening inhibition member on the shaft portion at a position closer to the top end of the shaft portion than the loosening inhibition member, preventing the loosening inhibition member from moving from the base end side of the shaft portion toward the top end side.

Description

Technical Field

[0001] The technology disclosed in this specification relates to a cutting tool. Background Technology

[0002] Patent Document 1 discloses a cutting tool comprising: a first blade; a second blade rotatable relative to the first blade; a base member supporting the first blade and the second blade; a threaded member comprising a head and a shaft extending from the head as a base end and having an external thread, wherein the first blade and the base member are fastened to each other by threading the external thread with an internal thread; and a loosening inhibition member mounted on the shaft, wherein the loosening of the threaded member is inhibited by being pressed by the head.

[0003] Existing technical documents

[0004] Patent documents

[0005] Patent Document 1: Japanese Patent Application Publication No. 2022-107440 Summary of the Invention

[0006] The problem the invention aims to solve

[0007] In cutting tools like those in Patent Document 1, when the threaded component is removed from the cutting tool, the loosening inhibition member may detach from the threaded component (specifically, the tip of the shaft). This specification provides a technique that can prevent the loosening inhibition member from detaching from the threaded component.

[0008] Solution for solving the problem

[0009] The cutting tool disclosed in this specification includes: a first cutter; a second cutter rotatable relative to the first cutter; a base member supporting the first cutter and the second cutter; a threaded member comprising a head and a shaft extending from the head as a base end and having an external thread, wherein the first cutter and the base member are fastened together by threading the external thread with an internal thread; a loosening inhibition member mounted on the shaft, which is pressed by the head to inhibit loosening of the threaded member; and a detachment inhibition member mounted adjacent to the loosening inhibition member on the shaft at a position closer to the top end of the shaft than the loosening inhibition member, which inhibits the loosening inhibition member from moving from the base end side of the shaft toward the top end side.

[0010] According to the above structure, a detachment-preventing member that inhibits the loosening of the member from moving from the base end to the top end of the shaft is provided on the threaded member. Therefore, it is possible to prevent the loosening-preventing member from detaching from the threaded member.

[0011] Furthermore, the term "loosening of the threaded component" as used in this specification specifically refers to the loosening of the threaded component when it is locked. Additionally, the term "dislodgement of the loosening inhibition component" as used in this specification specifically refers to the dislodgement of the loosening inhibition component after the threaded component has been removed by the self-cutting tool. Attached Figure Description

[0012] Figure 1 This is a perspective view of the pruning shears 2 in the embodiment, viewed from the upper left front.

[0013] Figure 2 This is an exploded view showing the state of the constituent parts provided on the front side of the pruning shears 2 in the embodiment after being decomposed in the left-right direction.

[0014] Figure 3 This is an enlarged view of the front of the pruning shears 2 in the embodiment, viewed from the left.

[0015] Figure 4 This is a cross-sectional view showing the state in which the pruning shears 2 in the embodiment are tightened using locking screws 44.

[0016] Figure 5 This is a diagram showing the internal structure of the pruning shears 2 in the embodiment when the operation mode is normal and the trigger lever 10 is not pulled, as viewed from the right.

[0017] Figure 6 This is a perspective view of the trigger lever 10, gear housing 16, and sensor substrate 208 of the pruning shears 2 in the embodiment, viewed from the upper right front.

[0018] Figure 7 This is a diagram showing the internal structure of the pruning shears 2 in the embodiment when the operation mode is normal and the trigger lever 10 is pulled, as viewed from the right.

[0019] Figure 8 This is a perspective view of the movable blade 8 and blade holder 38 of the pruning shears 2 in the embodiment, viewed from the upper left rear.

[0020] Figure 9 The diagram schematically illustrates the switching of the opening position of the movable blade 8 in the pruning shears 2 of the embodiment between the first opening position P1 and the second opening position P2.

[0021] Explanation of reference numerals in the attached figures

[0022] 2. Pruning shears; 4. Outer casing; 6. Fixed blade; 8. Movable blade; 10. Trigger lever; 12. Left outer casing; 14. Right outer casing; 16. Gear casing; 18. Cover casing; 20. Handle; 22. Protective part; 24. Battery mounting part; 26. Operating unit; 28. Power switch; 30. Adjustment switch; 32. Display unit; 36. Common fastening bolt; 38. Blade holder; 38a. Mounting hole; 38b. Magnet; 40. 42. Connecting pin; 44. Common fastening nut; 46. Locking screw; 48. Locking plate; 49. O-ring seal; 50. External threaded part; 51. Fitting part; 52. Cylindrical part; 53. Fitting hole; 54. First through hole; 65. Second through hole; 66. First cylindrical part; 67. Bevel gear; 68. Third through hole; 79. Fourth through hole; 70. Fifth through hole; 72. Sixth through hole; 74. Second cylindrical part; 75. Internal thread; 76. 80. Internal thread; 82. Shaft; 84. Head; 86. External thread; 87. Plate body; 88. Multiple teeth of the locking plate; 90. 7th through hole; 92. Abutment surface; 94. Multiple teeth of the common fastening nut; 96. Recess; 96a. Bottom surface; 96b. Inclined surface; 98. Left surface of the locking plate; 100. Right surface of the locking plate; 102. Left corner of the plate body; 104. Right corner of the plate body; 202. Control device; 2 04. Electric motor; 206. Power transmission mechanism; 208. Sensor substrate; 208a. Screw; 208b. Screw; 212. Gear shaft; 214. Bevel gear; 218. Opening; 220. Base; 222. Operating part; 224. Protrusion; 226. Magnet; 228. Rotating pin; 230. Compression spring; 232. First magnetic sensor; 234. Second magnetic sensor; 236. Third magnetic sensor; B. Battery pack. Detailed Implementation

[0023] The present invention will now be described in detail with reference to the accompanying drawings, providing representative and non-limiting examples. This detailed description is merely intended to show those skilled in the art the details of preferred embodiments for carrying out the invention, and is not intended to limit the scope of the invention. Furthermore, to provide a further improved cutting tool, the disclosed additional features and technical solutions may be used independently of other features and technical solutions, or in combination with other features and technical solutions.

[0024] Furthermore, the combinations of features and processes disclosed in the following detailed description are not, in the broadest sense, necessary for carrying out the invention, but are described only to illustrate representative specific examples of the invention. Moreover, in providing additional and useful embodiments of the invention, the various features of the following representative examples and the various features recited in the claims are not necessarily to be combined in the same order as the specific examples described herein or in the listed order.

[0025] All features set forth in this specification and / or claims are intended to be disclosed separately and independently from the structure of the embodiments and / or features set forth in the claims, as limitations on the original application disclosure and specific matters set forth in the claims. Furthermore, all numerical ranges and descriptions relating to organizations or groups are intended to limit the original application disclosure and specific matters set forth in the claims, with the intention of disclosing the aforementioned intermediate structure.

[0026] In one or more embodiments, the loosening inhibition member may include: a first surface facing the base end side of the shaft portion; and a second surface facing the top end side of the shaft portion. Alternatively, the shape of the first surface when viewed from the base end side of the shaft portion and the shape of the second surface when viewed from the top end side of the shaft portion may be different.

[0027] If the shape of the first surface viewed from the base end of the shaft is the same as the shape of the second surface viewed from the top end of the shaft, then even if the orientation of the first surface and the orientation of the second surface are interchanged, the loosening suppression function of the loosening suppression member will not be significantly impaired. In the above structure, the shape of the first surface viewed from the base end of the shaft and the shape of the second surface viewed from the top end of the shaft are different. Therefore, if the orientation of the first surface and the orientation of the second surface are interchanged, the loosening suppression function of the loosening suppression member may be impaired. Here, if the loosening suppression member falls off the threaded member, when the user installs the fallen loosening suppression member on the threaded member, the orientation of the first surface and the orientation of the second surface may be interchanged. As a result, the loosening suppression function of the loosening suppression member may be impaired. Therefore, in the above structure, it is particularly desirable to suppress the falling off of the loosening suppression member. According to the above structure, since the loosening suppression member can be prevented from falling off the threaded member, the effect of suppressing the falling off of the loosening suppression member can be significantly achieved.

[0028] In one or more embodiments, the loosening inhibition member may include: a plate portion extending in a generally frustum shape that expands in diameter toward the top end of the shaft portion; and a plurality of teeth disposed along at least one of the inner and outer circumferences of the plate portion and protruding in the direction of extension of the plate portion. Alternatively, the detachment inhibition member may be a generally annular elastic member.

[0029] In this specification, the component that presses against the loosening inhibition member between the head and the counterweight is also referred to as the counterweight component. In the above structure, the loosening inhibition member causes multiple teeth to engage with at least one of the head and the counterweight component in order to generate a frictional torque for inhibiting the loosening of the screw component. However, if the plate is excessively flattened by the force (so-called axial force) exerted by the head and the counterweight component on the plate, the multiple teeth will not engage with at least one of the head and the counterweight component. As a result, the frictional torque for inhibiting the loosening of the threaded component decreases, and the loosening inhibition function of the loosening inhibition member decreases. According to the above structure, the detachment inhibition member installed adjacent to the plate extends into the inner side of the plate (i.e., the inner side, which is approximately frustum-shaped). The detachment inhibition member extending into the inner side of the plate supports the inner surface of the plate in the axial direction. Therefore, it is possible to inhibit the excessive flattening of the plate by the axial force, and thus it is possible to prevent the multiple teeth from engaging with at least one of the head and the counterweight component. This increases the frictional torque used to suppress loosening of threaded components, thereby improving the loosening suppression function of the loosening suppression component.

[0030] In one or more embodiments, the first blade or the base component may include: a through hole through which the shaft portion passes; an abutment surface for the loosening inhibition member to abut; and a recess disposed along the periphery of the through hole, such that at least a portion of the detachment inhibition member is retracted to a position further inward than the abutment surface.

[0031] The detachment suppression member is deformed by being pressed axially between the loosening suppression member and the opposing member. If the detachment suppression member deforms excessively, it may break. According to the above structure, the first blade or base member corresponding to the opposing member includes an abutment surface that contacts the loosening suppression member and a recess that at least partially retracts the detachment suppression member to a position further inward than the abutment surface. The abutment surface and the recess make the space between the loosening suppression member and the opposing member larger. Therefore, the amount of deformation of the detachment suppression member when it is sandwiched between the loosening suppression member and the opposing member can be reduced. Thus, excessive deformation of the detachment suppression member can be suppressed, and therefore, breakage of the detachment suppression member can be prevented.

[0032] In one or more embodiments, the recess may be smoothly connected to the abutment surface.

[0033] If the connection between the recess and the contact surface has an uneven shape (e.g., a sharp shape), the load acting on the detachment suppression member may become excessive locally when the member comes into contact with this connection. This could lead to the detachment suppression member breaking. According to the structure described above, since the connection between the recess and the contact surface has a smooth shape (e.g., a rounded shape or a chamfered shape), it is possible to prevent the load acting on the detachment suppression member from becoming excessive locally when it comes into contact with this connection. This prevents the detachment suppression member from breaking.

[0034] In one or more embodiments, the cutting tool may include: a motor shaft connected to the second blade; and an electric motor that rotates the motor shaft. Alternatively, the cutting action may be performed by driving the electric motor to rotate the first blade and the second blade relative to each other.

[0035] In manual cutting tools that utilize force applied by the user to perform the cutting action (i.e., rotation of the second cutter relative to the first cutter), the components other than the first and second cutters are relatively inexpensive. Therefore, if the first and second cutters wear out, they are usually replaced along with the cutting tool. Thus, it is considered that in manual cutting tools, the frequency of removing the first cutter from the base component (i.e., the frequency of removing the threaded component from the cutting tool) is low. In contrast, the cutting tool described above is an electric cutting tool that utilizes power from an electric motor to perform the cutting action. In electric cutting tools, the components other than the first and second cutters (e.g., the electric motor) are relatively expensive. Therefore, if the first and second cutters wear out, sometimes only the first and second cutters are replaced. That is, the first and second cutters can be replaced. Therefore, in electric cutting tools, the frequency of removing the first cutter from the base component (i.e., the frequency of removing the threaded component from the cutting tool) is expected to be high, and therefore, it is particularly desirable to suppress the detachment of loosening inhibition components. Based on the above structure, in an electric cutting tool, it is possible to prevent the loosening inhibition member from falling off the threaded member. Therefore, it can significantly prevent the loosening inhibition member from falling off.

[0036] In one or more embodiments, the shedding inhibition member may be installed on the shaft portion in a radially expanded state.

[0037] If there is clearance between the detachment suppression member and the shaft, the detachment suppression member may sometimes wobble relative to the shaft. If the detachment suppression member wobbles relative to the shaft, the detachment suppression member and the shaft will collide with each other, potentially causing wear of the detachment suppression member (or the shaft). According to the structure described above, since no clearance is generated between the detachment suppression member and the shaft, wobble of the detachment suppression member relative to the shaft can be suppressed. Therefore, wear of the detachment suppression member (or the shaft) can be suppressed.

[0038] In one or more embodiments, the detachment inhibition member may be obscured by the loosening inhibition member when viewed from the base end side of the shaft portion.

[0039] If the detachment suppression member is not obscured by the loosening suppression member when viewed from the base end of the shaft, the appearance of the cutting tool may be compromised. According to the structure described above, since the detachment suppression member is obscured by the loosening suppression member when viewed from the base end of the shaft, the appearance of the cutting tool can be improved.

[0040] (Example)

[0041] like Figure 1 As shown, the cutting tool in this embodiment is pruning shears 2. Pruning shears 2 are mainly used for cutting branches and other branches. Pruning shears 2 can be held and carried by the user with one hand.

[0042] The pruning shears 2 include a housing 4, a fixed blade 6, a movable blade 8, a trigger lever 10, and a battery pack B. The pruning shears 2 perform a cutting action by using electricity supplied from the battery pack B to rotate the movable blade 8 relative to the fixed blade 6 in response to a pulling operation of the trigger lever 10; details will be explained later. The fixed blade 6 and the movable blade 8 are made of metal (e.g., iron). The battery pack B houses a rechargeable secondary battery such as a lithium-ion battery.

[0043] The outer casing 4 includes a left outer casing 12, a right outer casing 14, a gear casing 16, and a cover casing 18. The left outer casing 12, right outer casing 14, gear casing 16, and cover casing 18 are all made of plastic. The left outer casing 12 and right outer casing 14 are fixed to each other using screws (not shown). The gear casing 16 is supported by the left outer casing 12 and right outer casing 14. The cover casing 18 is fixed relative to the left outer casing 12 and right outer casing 14 using screws (not shown). The outer casing 4 defines a gripping part 20 for user handling, a protective part 22 for protecting the trigger lever 10, and a battery mounting part 24 for detachable installation of the battery pack B.

[0044] exist Figures 1-9 In the gripping section 20, along its length, the direction from the battery mounting section 24 toward the fixed blade 6 and the movable blade 8 is defined as the forward direction, and the direction from the fixed blade 6 and the movable blade 8 toward the battery mounting section 24 is defined as the rearward direction. Furthermore, the direction orthogonal to the forward / backward direction and along the rotation axis of the movable blade 8 is defined as the left / right direction. In the left / right direction, the direction from the movable blade 8 toward the fixed blade 6 is defined as the leftward direction, and the direction from the fixed blade 6 toward the movable blade 8 is defined as the rightward direction. Additionally, the direction orthogonal to both the forward / backward and left / right directions is defined as the up / down direction.

[0045] An operation unit 26 is located at the upper rear of the housing 4. The operation unit 26 includes a power switch 28 for switching the main power supply on / off and an adjustment switch 30 (details will be explained later). In addition, a display unit 32 is located at the upper front of the housing 4. The display unit 32 includes LEDs (not shown) for displaying the on / off status of the main power supply, the remaining battery level of the battery pack B, etc.

[0046] like Figure 2 As shown, the pruning shears 2 also include a common fastening bolt 36, a blade holder 38, a connecting pin 40, a common fastening nut 42, a locking screw 44, a locking plate 46, and an O-ring seal 48. In this embodiment, the central axis of the common fastening bolt 36 (specifically, the cylindrical portion 54) is shown as "axis A1". The central axis of the connecting pin 40 is shown as "axis A2". The central axis of the locking screw 44 (specifically, the shaft portion 80) is shown as "axis A3". Axis axes A1, A2, and A3 extend in the left-right direction, respectively.

[0047] The common fastening bolt 36 has, from left to right, an external thread portion 50, a mating portion 52, and a cylindrical portion 54. The common fastening bolt 36 is a so-called stepped bolt. The mating portion 52 has a shape corresponding to the mating hole 56 provided in the gear housing 16.

[0048] The blade holder 38 includes a first through hole 58 and a second through hole 60 located in front of the first through hole 58. The first through hole 58 receives the cylindrical portion 54 of the common fastening bolt 36 in a rotatable manner. Therefore, the blade holder 38 can rotate about axis A1. The right portion of the connecting pin 40 is inserted into the second through hole 60. The connecting pin 40 is fixed to the blade holder 38 in the state of being inserted into the second through hole 60. In addition, a bevel gear 64 and a first cylindrical portion 62 protruding to the left from the periphery of the first through hole 58 are formed on the left surface of the blade holder 38.

[0049] The movable blade 8 includes a third through hole 66 into which the first cylindrical portion 62 of the blade holder 38 is inserted, and a fourth through hole 68 into which the left portion of the connecting pin 40 is inserted. The movable blade 8 is constrained by the blade holder 38 on axes A1 and A2. That is, the movable blade 8 is fixed to the blade holder 38 in the front-back and up-down directions. Thus, the movable blade 8 can rotate integrally with the blade holder 38 about axis A1.

[0050] The fixed blade 6 includes a fifth through hole 70 and a sixth through hole 72 located behind the fifth through hole 70. A second cylindrical portion 74 protruding to the right from the right surface of the gear housing 16 is inserted into the fifth through hole 70. An internal thread 76 is provided on the inner side of the sixth through hole 72.

[0051] The common fastening nut 42 has an internal thread 78 corresponding to the external thread 50 of the common fastening bolt 36. The common fastening bolt 36 and the common fastening nut 42 fasten the blade holder 38, the movable blade 8, and the fixed blade 6 to the gear housing 16 by threading the external thread 50 with the internal thread 78. Specifically, the common fastening bolt 36 and the common fastening nut 42 constrain the blade holder 38, the movable blade 8, and the fixed blade 6 in the left-right direction. By tightening (or loosening) the common fastening nut 42 relative to the common fastening bolt 36, the user can adjust the force (hereinafter referred to as "locking force") used to lock the gear housing 16, the fixed blade 6, the movable blade 8, and the blade holder 38 in the left-right direction. Furthermore, if the locking force is too weak, the gap between the fixed blade 6 and the movable blade 8 will widen, potentially reducing the sharpness of the pruning shears 2. On the other hand, if the locking force is too strong, the resistance generated in the movable blade 8 when rotating relative to the fixed blade 6 will increase. This could potentially lead to issues with the electric motor 204 (see reference) that rotates the movable blade 8. Figure 5 The load on battery pack B increases, or the battery capacity of battery pack B is depleted more quickly. Therefore, the locking torque of the common fastening nut 42 relative to the common fastening bolt 36 has an appropriate range.

[0052] The locking screw 44 includes a shaft portion 80 and a head 82. An external thread 84 is formed on the shaft portion 80, which corresponds to the internal thread 76 provided on the fixing blade 6. The locking screw 44 is made of metal (e.g., iron). A locking plate 46 and an O-ring 48 are mounted around the shaft portion 80 of the locking screw 44. The locking plate 46 can also be described as a washer. The locking plate 46 is made of metal (e.g., iron). Furthermore, the O-ring 48 is made of rubber (e.g., NBR). The O-ring 48 is positioned closer to the top end of the shaft portion 80 than the locking plate 46. In the unloaded state, the inner diameter of the O-ring 48 is smaller than the outer diameter of the shaft portion 80. Therefore, the O-ring 48 is mounted on the shaft portion 80 in a state where it is radially expanded along the axis A3. Furthermore, in this state, the outer diameter of the O-ring 48 is larger than the inner diameter of the locking plate 46. Therefore, if the locking plate 46 moves towards the top end of the shaft portion 80, the locking plate 46 abuts against the O-ring seal 48, thereby preventing further movement towards the top end of the shaft portion 80. This prevents the locking plate 46 from dislodging from the shaft portion 80, for example, when the top end of the shaft portion 80 is facing downwards. Furthermore, as... Figure 3 As shown, the locking plate 46 includes a plate body 86 and a plurality of teeth 88 disposed along the outer periphery of the plate body 86. When viewed from the left, the O-ring 48 (see reference) Figure 2 It is blocked by the locking plate 46.

[0053] like Figure 2As shown, a seventh through hole 90 is provided behind the fitting hole 56 in the gear housing 16, through which the shaft portion 80 of the locking screw 44 can pass. With the shaft portion 80 of the locking screw 44 passing through the seventh through hole 90, if the external thread 84 is threaded into the internal thread 76 of the fixing tool 6, then as... Figure 4 The fixing blade 6 shown is fastened to the gear housing 16. Thus, the fixing blade 6 is fixed to the gear housing 16.

[0054] like Figure 3 As shown, a contact surface 92 for receiving the common fastening nut 42 and the locking plate 46 is provided on the left surface of the gear housing 16. The contact surface 92 is a plane that is approximately orthogonal to the left-right direction. Furthermore, a plurality of teeth 94 corresponding to the plurality of teeth 88 of the locking plate 46 are formed on the outer periphery of the common fastening nut 42. Additionally, for simplification, except... Figure 3 and Figure 4 The multiple teeth 94 of the common fastening nut 42 are omitted from the illustrations in the accompanying drawings.

[0055] When fixing the retaining blade 6 relative to the gear housing 16, the locking screw 44 is used to tighten the lock while the multiple teeth 88 of the locking plate 46 are engaged with the multiple teeth 94 of the common fastening nut 42. Since rotation of the locking plate 46 relative to the gear housing 16 is prohibited after tightening with the locking screw 44, rotation of the common fastening nut 42 engaged with the locking plate 46 is also prohibited. This prevents unexpected changes in the locking force due to loosening of the common fastening nut 42.

[0056] Furthermore, if you wish to adjust the locking force by tightening (or loosening) the common fastening nut 42, you must first loosen the locking screw 44 to remove it. When removing the locking screw 44, if the locking plate 46 is moved to the left along axis A3, the engagement between the common fastening nut 42 and the locking plate 46 is disengaged. This allows rotation of the common fastening nut 42, thus enabling adjustment of the locking force.

[0057] like Figure 4 As shown, the gear housing 16 has a recess 96 that is provided along the periphery of the 7th through hole 90 and recessed to the right relative to the abutment surface 92. The recess 96 includes a bottom surface 96a and an inclined surface 96b. The bottom surface 96a connects to the periphery of the 7th through hole 90 and extends substantially parallel to the abutment surface 92. The inclined surface 96b smoothly connects the bottom surface 96a and the abutment surface 92. The inclined surface 96b gradually approaches the bottom surface 96a as it approaches the axis A3. The inclined surface 96b gradually approaches the abutment surface 92 as it moves away from the axis A3. Furthermore, the depth of the recess 96 (specifically the bottom surface 96a) relative to the abutment surface 92 is approximately half the width of the O-ring 48 in the unloaded state.

[0058] The left surface 98 and the right surface 100 of the locking plate 46 (plate body 86 and multiple teeth 88) are both generally conical surfaces that expand in diameter as they move toward the top end of the shaft portion 80. That is, the locking plate 46 (plate body 86 and multiple teeth 88) has a generally frustum-shaped shape that expands in diameter as it moves toward the top end of the shaft portion 80.

[0059] With the locking screw 44 fastened, the left corner 102 of the plate body 86 abuts against the head 82 of the locking screw 44. The right corner 104 of the plate body 86 (or, more specifically, the corners of each of the multiple teeth 88) abuts against the contact surface 92. In this state, the left corner 102 engages with the head 82, and the right corner 104 engages with the contact surface 92. This generates a frictional torque that inhibits the rotation of the head 82 relative to the contact surface 92, thus preventing the locking screw 44 from loosening.

[0060] Furthermore, with the locking screw 44 in the tightened state, the O-ring 48 is pressed between the bottom surface 96a of the recess 96 and the right surface 100 of the plate body 86. In this state, the O-ring 48 exerts a force on the right surface 100 of the plate body 86 to the left relative to the bottom surface 96a (i.e., the gear housing 16). This prevents the locking plate 46 from being flattened by the head 82 of the locking screw 44. That is, it prevents the locking plate 46 from deforming axially along the axis A3.

[0061] The elastic restoring force from the locking plate 46 and the elastic restoring force from the O-ring 48 act as axial forces on the locking screw 44. That is, both the locking plate 46 and the O-ring 48 are components that impart axial force to the locking screw 44. Furthermore, from the viewpoint of imparting axial force to the locking screw 44, it is desirable that the O-ring 48 is moderately flattened to ensure sufficient contact area with other components (gear housing 16 and locking plate 46). On the other hand, from the viewpoint of durability, it is desirable that the O-ring 48 has a certain degree of resistance to flattening. Based on the above, for example, the tensile strength of the O-ring 48 is desired to be in the range of 10 MPa to 30 MPa. The tensile strength of the O-ring 48 mentioned here is used as one of the indicators of the O-ring 48's resistance to flattening. Moreover, in this embodiment, the tensile strength of the O-ring 48 is approximately 20 MPa.

[0062] like Figure 5As shown, the pruning shears 2 also include a control device 202, an electric motor 204, a power transmission mechanism 206, and a sensor substrate 208. The control device 202, electric motor 204, power transmission mechanism 206, and sensor substrate 208 are housed inside the housing 4. The control device 202 is located at the rear of the housing 4. The electric motor 204 is located in front of the control device 202. The length direction of the electric motor 204 is along the front-to-back direction. The power transmission mechanism 206 is located in front of the electric motor 204. The sensor substrate 208 is located at the front of the housing 4.

[0063] The control device 202 includes a memory and a CPU. The control device 202 is electrically connected to the operation unit 26, the display unit 32, the electric motor 204, and the sensor substrate 208. Furthermore, with the battery pack B installed in the battery mounting section 24, the control device 202 is electrically connected to the battery pack B. The control device 202 controls the operation of the pruning shears 2 according to a predetermined program stored in the memory. For example, the control device 202 switches between a state allowing power supply from the battery pack B to the electric motor 204 and a state blocking power supply, corresponding to the on / off state of the main power supply. Furthermore, the control device 202 controls the display unit 32 to display the on / off state of the main power supply, the remaining battery level of the battery pack B, etc.

[0064] The electric motor 204 is, for example, a brushless motor. The electric motor 204 is powered to rotate a motor shaft (not shown) that extends in the front-rear direction.

[0065] The power transmission mechanism 206 includes a planetary gear mechanism (not shown) connected to the aforementioned motor shaft (not shown) and a gear shaft 212 connected to the planetary gear mechanism. The planetary gear mechanism transmits the rotation of the motor shaft to the gear shaft 212 at a reduced speed. That is, the planetary gear mechanism functions as a speed reducer. Furthermore, the gear shaft 212 is supported by bearings (not shown) disposed inside the gear housing 16, allowing it to rotate about an axis in the front-rear direction. A bevel gear 214 is formed at the front of the gear shaft 212, which connects with a bevel gear 64 (see reference) formed on the left surface of the blade holder 38. Figure 2 Correspondingly, a portion of the gear shaft 212 (bevel gear 214) meshes with the bevel gear 64 of the blade holder 38 via an opening 218 formed on the right surface of the gear housing 16. The bevel gears 64 and 214 convert the rotation of the gear shaft 212 into rotation of the blade holder 38 and the movable blade 8 about axis A1. Therefore, when driving the electric motor 204, power is transmitted to the movable blade 8 via the motor shaft, planetary gear mechanism, gear shaft 212, and bevel gears 64 and 214. This causes the movable blade 8 to rotate.

[0066] like Figure 6As shown, the trigger lever 10 includes a base 220, an operating portion 222 extending rearward and downward from near the rear end of the base 220, and a protrusion 224 protruding upward from the upper surface of the base 220. A magnet 226 is fixed to the right surface of the base 220. A rotating pin 228 extending in the left-right direction is inserted into the center of the base 220. The rotating pin 228 is supported by the gear housing 16 and is rotatable. This allows the trigger lever 10 to rotate about the rotating pin 228. Figure 5 As shown, the operating part 222 is the portion of the trigger lever 10 exposed outside the housing 4, and is operated by the user. Furthermore, a compression spring 230 is installed around the protrusion 224. The compression spring 230 enters a recess (not shown) provided on the lower surface of the gear housing 16. Thus, the compression spring 230 is held between the gear housing 16 and the trigger lever 10. The compression spring 230 exerts a downward force on the operating part 222 of the trigger lever 10 relative to the gear housing 16. Therefore, when the user does not operate the operating part 222, the trigger lever 10 remains in a position... Figure 5 The position shown is such that when the user pulls the operating unit 222, the trigger lever 10 rotates clockwise as viewed from the right, overcoming the force of the compression spring 230. Furthermore, when the user pulls the operating unit 222 to its maximum extent, the trigger lever 10 is positioned as follows: Figure 7 The location shown.

[0067] like Figure 6 As shown, the sensor substrate 208 is fixed to the gear housing 16 using screws 208a and 208b. The sensor substrate 208 extends approximately orthogonally to the left-right direction. A first magnetic sensor 232, a second magnetic sensor 234, and a third magnetic sensor 236 are provided on the sensor substrate 208. The first magnetic sensor 232 is located near the lower end of the sensor substrate 208. The second magnetic sensor 234 is located above and behind the first magnetic sensor 232. The third magnetic sensor 236 is located above the second magnetic sensor 234. The first magnetic sensor 232, the second magnetic sensor 234, and the third magnetic sensor 236 can detect magnetism and output their detection results to the control device 202 (see reference). Figure 5 The detection results output to the control device 202 may indicate, for example, the strength of the magnetism and the direction of the magnetic field.

[0068] When the trigger lever 10 is pulled, the position of the magnet 226 relative to the sensor substrate 208 changes. For example, when the trigger lever 10 is in the position... Figure 5 In the position shown, magnet 226 (refer to) Figure 6 Located on the left surface of the sensor substrate 208 and adjacent to the first magnetic sensor 232 (see reference). Figure 6The relative positions of the parts. When the trigger operating lever 10 is in Figure 7 In the position shown, magnet 226 is located on the left surface of sensor substrate 208, where a second magnetic sensor 234 is located (see reference). Figure 6 The relative positions of parts of the magnet 226. When the position of the magnet 226 changes, the magnetic changes are detected by the first magnetic sensor 232, the second magnetic sensor 234, and the third magnetic sensor 236. Therefore, the control device 202 (refer to...) Figure 5 The control device 202 can determine whether the trigger lever 10 has been pulled based on the output of at least one of the first magnetic sensor 232, the second magnetic sensor 234, and the third magnetic sensor 236 (in this embodiment, the first magnetic sensor 232). Furthermore, the control device 202 can determine the amount of pull of the trigger lever 10 based on the output of at least one of the first magnetic sensor 232, the second magnetic sensor 234, and the third magnetic sensor 236.

[0069] like Figure 8 As shown, a mounting hole 38a is formed between the first cylindrical portion 62 and the bevel gear 64 on the left surface of the blade holder 38. A magnet 38b is mounted in the mounting hole 38a. When the movable blade 8 and the blade holder 38 rotate about axis A1, the position of the magnet 38b relative to the sensor substrate 208 changes. For example, when the blade holder 38 is in a certain position... Figure 5 In the position shown, magnet 38b (refer to) Figure 8 ) is in contact with the second magnetic sensor 234 (reference) Figure 6 The relative positions. At the blade holder 38 Figure 7 In the position shown, magnet 38b is in contact with the third magnetic sensor 236 (reference). Figure 6 The relative positions of the magnet 38b and the magnetic changes detected by the first magnetic sensor 232, the second magnetic sensor 234, and the third magnetic sensor 236 when the position of the magnet 38b changes. Therefore, the control device 202 (refer to...) Figure 5 The rotation angle of the movable blade 8 (i.e., the position of the movable blade 8 relative to the housing 4) can be determined based on the output from at least one of the first magnetic sensor 232, the second magnetic sensor 234 and the third magnetic sensor 236 (in this embodiment, the second magnetic sensor 234 and the third magnetic sensor 236).

[0070] (Trimping Shears 2 in normal mode)

[0071] The following describes the operation of the pruning shears 2 under normal conditions. "Normal conditions" here refers, for example, to the time immediately after the main power is turned on and the user is performing cutting operations. In this embodiment, the operating mode of the pruning shears 2 at this time is referred to as the normal mode.

[0072] like Figure 5As shown, in the state where the trigger lever 10 is not pulled, the control device 202 drives the electric motor 204 to hold the movable blade 8 in the open position relative to the fixed blade 6 (also known as the open position). When the trigger lever 10 is pulled from this state, the control device 202 drives the electric motor 204 to close the movable blade 8 relative to the fixed blade 6 according to the amount of pull of the trigger lever 10. Specifically, the control device 202 rotates the movable blade 8 relative to the fixed blade 6 by an amount corresponding to the amount of pull of the trigger lever 10. Figure 7 As shown, when the trigger lever 10 is pulled to its maximum position, the movable blade 8 remains in a closed position relative to the fixed blade 6 (also referred to as the closed position). When the pulling operation on the trigger lever 10 is released from this position, the control device 202 drives the electric motor 204 to return the movable blade 8 to the open position. In this way, the user can cause the pruning shears 2 to perform a cutting action by pulling the trigger lever 10.

[0073] like Figure 9 As shown, control device 202 (refer to) Figure 5 ) and adjustment switch 30 (refer to) Figure 1 The first operation (e.g., a short press) correspondingly switches the opening position of the movable blade 8 between a first open position P1 and a second open position P2, which is closer to the closed position than the first open position P1. Therefore, the user can select a suitable opening position according to the thickness of the object being cut. Furthermore, the opening position is not limited to the first open position P1 and the second open position P2; it can be switched to other positions.

[0074] (The fine-tuning mode for the cutting depth of the pruning shears 2)

[0075] In adjusting switch 30 (refer to) Figure 1When performing the second operation (long press operation), the control device 202 switches the operation mode of the pruning shears 2 to a fine-tuning mode for adjusting the cutting depth of the fixed blade 6 and the movable blade 8. The cutting depth referred to here is the width of the overlapping portion of the fixed blade 6 and the movable blade 8 in the circumferential direction along axis A1 when the movable blade 8 is in the closed position. If the cutting depth is too shallow, the object to be cut may not be completely severed using the fixed blade 6 and the movable blade 8. Although not illustrated, in the fine-tuning mode, the control device 202 increases the cutting depth each time the trigger lever 10 is pulled. After a predetermined number of pulls on the trigger lever 10, the control device 202 restores the cutting depth to its original state. Thus, the user can adjust the cutting depth to an appropriate depth by pulling the trigger lever 10. In addition, in the fine-tuning mode of cutting depth, when the third operation (short press or long press) is performed on the adjustment switch 30, the control device 202 switches the operation mode of the pruning shears 2 to the normal mode.

[0076] (Modified Example)

[0077] The cutting tool can also be a manual pruning shear. For example, the cutting tool can also be a tool consisting of a pair of handles that can rotate relative to each other, each fixed with a blade similar to a fixed blade 6 and a movable blade 8. In this case, a locking screw 44 can be used to secure the handle and the blade together by fastening the blade to the handle. Alternatively, one of the handle and the blade can have an internal thread 76 corresponding to the external thread 84 of the locking screw 44. The other of the handle and the blade can also have an abutment surface 92 and a recess 96.

[0078] The shape of the locking plate 46 can also be appropriately changed. For example, the locking plate 46 can also be formed into a generally circular plate shape. In addition, the locking plate 46 can also be formed to be bilaterally symmetrical.

[0079] Alternatively, components other than the locking plate 46 may be installed on the locking screw 44 to prevent the locking screw 44 from loosening. For example, toothed washers, wave washers, cup washers, etc., may be installed on the locking screw 44 as components to prevent the locking screw 44 from loosening.

[0080] Alternatively, a component other than the O-ring 48 may be installed on the locking screw 44 as a component to prevent the locking plate 46 from falling off. For example, an annular component (e.g., a rubber band) with a different shape from the O-ring 48 may also be installed on the locking screw 44 as a component to prevent the locking plate 46 from falling off.

[0081] Alternatively, the recess 96 may not be provided in the gear housing 16.

[0082] The inclined surface 96b of the recess 96 may not smoothly connect the bottom surface 96a and the abutment surface 92. That is, the inclination angle of the inclined surface 96b may vary discretely between the bottom surface 96a and the abutment surface 92.

[0083] The internal thread 76 may be provided in the 7th through hole 90 instead of the 6th through hole 72. In this case, the external thread 84 of the locking screw 44 can pass through the 6th through hole 72 and engage with the internal thread 76 provided in the 7th through hole 90. Alternatively, when the fastening is completed using the locking screw 44, the fixing blade 6 is clamped between the head 82 of the locking screw 44 and the gear housing 16.

[0084] The materials used for the various components of the pruning shears 2 (e.g., housing 4, fixed blade 6, movable blade 8, locking screw 44, locking plate 46, and O-ring 48) can be appropriately changed. For example, the housing 4 can be made of a metal such as aluminum. For example, the fixed blade 6, movable blade 8, locking screw 44, and locking plate 46 can each be made of metals other than iron. For example, the O-ring 48 can be made of rubber such as SBR, Si, or SR. Furthermore, the O-ring 48 can also be made of an elastomer instead of rubber.

[0085] The pruning shears 2's action modes are not limited to the normal mode and the fine-tuning mode for cutting depth; other modes can also be switched to.

[0086] The pruning shears 2 can also have a power cable that can be connected to an external power source, replacing the battery mounting unit 24. The external power source can be a commercial power source or a portable power supply device. The power supply device can also be a device that can install multiple battery packs B, or a device that can supply power from multiple battery packs B to the pruning shears 2.

[0087] (Correspondence)

[0088] As described above, in one or more embodiments, the pruning shears 2 (an example of a cutting tool) include: a fixed blade 6 (an example of a first blade); a movable blade 8 (an example of a second blade) which is rotatable relative to the fixed blade 6; a gear housing 16 (an example of a base member) which supports the fixed blade 6 and the movable blade 8; a locking screw 44 (an example of a threaded member) which includes a head 82 and a shaft portion 80 extending from the head 82 as a base end and having an external thread 84, thereby fastening the fixed blade 6 and the gear housing 16 to each other by threading the external thread 84 with the internal thread 76; a locking plate 46 (a loosening inhibition member) which is mounted on the shaft portion 80 and is pressed by the head 82 to inhibit the loosening of the locking screw 44; and an O-ring seal 48 (an example of a detachment inhibition member) which is mounted on the shaft portion 80 adjacent to the locking plate 46 at a position closer to the top end of the shaft portion 80 than the locking plate 46, and inhibits the locking plate 46 from moving from the base end side of the shaft portion 80 toward the top end side.

[0089] According to the above structure, an O-ring 48 is provided on the locking screw 44 to prevent the locking plate 46 from moving from the base end side to the top end side of the shaft portion 80. Therefore, it is possible to prevent the locking plate 46 from falling off the locking screw 44.

[0090] In one or more embodiments, the locking plate 46 includes: a left surface 98 (an example of the first surface) facing the base end side of the shaft portion 80; and a right surface 100 (an example of the second surface) facing the top end side of the shaft portion 80. The shape of the left surface 98 when viewed from the base end side of the shaft portion 80 and the shape of the right surface 100 when viewed from the top end side of the shaft portion 80 are different from each other.

[0091] If the shape of the left surface 98 viewed from the base end of the shaft portion 80 is the same as the shape of the right surface 100 viewed from the top end of the shaft portion 80, then even if the orientations of the left surface 98 and the right surface 100 are reversed, the loosening prevention function of the locking plate 46 will not be significantly impaired. In the above structure, the shape of the left surface 98 viewed from the base end of the shaft portion 80 and the shape of the right surface 100 viewed from the top end of the shaft portion 80 are different. Therefore, if the orientations of the left surface 98 and the right surface 100 are reversed, the loosening prevention function of the locking plate 46 may be impaired. Furthermore, if the locking plate 46 detaches from the locking screw 44, when the user reattaches the detached locking plate 46 to the locking screw 44, the orientations of the left surface 98 and the right surface 100 may be reversed. This could potentially impair the loosening prevention function of the locking plate 46. Therefore, in the above structure, it is particularly desirable to suppress the detachment of the locking plate 46. Based on the above structure, since the locking plate 46 can prevent the locking screw 44 from falling off, it can significantly prevent the locking plate 46 from falling off.

[0092] In one or more embodiments, the locking plate 46 includes: a plate body 86 (an example of a plate portion) extending along a generally frustum shape that expands in diameter toward the top end of the shaft portion 80; and a plurality of teeth 88 disposed along the outer periphery of the plate body 86 (an example of at least one of an inner periphery and an outer periphery) and protruding in the direction of extension of the plate body 86. The O-ring seal 48 is a generally annular rubber member (an example of an elastic member).

[0093] In the above structure, the locking plate 46 engages multiple teeth 88 into the gear housing 16 (an example of a counter-component) to generate frictional torque for preventing the locking screw 44 from loosening. However, if the plate body 86 is excessively flattened by the force (so-called axial force) exerted by the head 82 and the gear housing 16 pressing against it, the multiple teeth 88 will not engage into the gear housing 16. As a result, the frictional torque for preventing the locking screw 44 from loosening decreases, and the loosening prevention function of the locking plate 46 decreases. According to the above structure, an O-ring seal 48 installed adjacent to the plate body 86 extends into the inner side of the plate body 86 (i.e., the approximately frustum-shaped inner side). The O-ring seal 48 extending into the inner side of the plate body 86 axially supports the right surface 100 of the plate body 86 (an example of the inner side of the plate). Therefore, it is possible to prevent the plate body 86 from being excessively flattened by the axial force, and thus it is possible to prevent the multiple teeth 88 from failing to engage into the gear housing 16. This increases the frictional torque used to suppress the loosening of the locking screw 44, thereby improving the loosening suppression function of the locking plate 46.

[0094] In one or more embodiments, the fixing blade 6 or gear housing 16 includes: a seventh through hole 90 (an example of a through hole) through which the shaft portion 80 passes; an abutment surface 92 for the locking plate 46 to abut; and a recess 96 provided along the periphery of the seventh through hole 90 such that approximately half of the O-ring seal 48 (at least a partial example of a detachment inhibition member) is retracted to a position further inward than the abutment surface 92.

[0095] The O-ring 48 is deformed by being pressed axially between the locking plate 46 and the gear housing 16. If the O-ring 48 is excessively deformed, it may break. According to the above structure, the gear housing 16 includes an abutment surface 92 that abuts against the locking plate 46 and a recess 96 that recesses approximately half of the O-ring 48 beyond the abutment surface 92. The abutment surface 92 and the recess 96 make the space between the locking plate 46 and the gear housing 16 larger. Therefore, the amount of deformation of the O-ring 48 when it is sandwiched between the locking plate 46 and the gear housing 16 can be reduced. Thus, excessive deformation of the O-ring 48 can be suppressed, and therefore, breakage of the O-ring 48 can be prevented.

[0096] In one or more embodiments, the recess 96 is smoothly connected to the abutment surface 92.

[0097] If the connection between the recess 96 and the contact surface 92 has an uneven shape, the load acting on the O-ring 48 may become excessive locally when it contacts the connection. This could lead to the O-ring 48 breaking. According to the above structure, since the connection between the recess 96 and the contact surface 92 has a smooth shape, it is possible to prevent the load acting on the O-ring 48 from becoming excessive locally when it contacts the connection. This prevents the O-ring 48 from breaking.

[0098] In one or more embodiments, the pruning shears 2 include: a motor shaft connected to a movable blade 8; and an electric motor 204 that rotates the motor shaft. The cutting action is performed by driving the electric motor 204 to rotate the fixed blade 6 and the movable blade 8 relative to each other.

[0099] The pruning shears 2 described above utilize power from the electric motor 204 to perform the cutting action. In the pruning shears 2, components other than the fixed blade 6 and the movable blade 8 (such as the electric motor 204) are relatively expensive. Therefore, if the fixed blade 6 and the movable blade 8 wear out, sometimes only the fixed blade 6 and the movable blade 8 need to be replaced. That is, the fixed blade 6 and the movable blade 8 can be replaced. Therefore, in the pruning shears 2, the frequency of removing the fixed blade 6 from the gear housing 16 (i.e., the frequency of removing the locking screw 44 from the pruning shears 2) is expected to be relatively high, and therefore, it is particularly desirable to suppress the detachment of the locking plate 46. According to the above structure, in the pruning shears 2, it is possible to suppress the detachment of the locking plate 46 from the locking screw 44. Therefore, the effect of suppressing the detachment of the locking plate 46 can be significantly achieved.

[0100] In one or more embodiments, the O-ring 48 may be installed on the shaft 80 in a radially expanded state.

[0101] If there is clearance between the O-ring 48 and the shaft portion 80, the O-ring 48 may sometimes wobble relative to the shaft portion 80. If the O-ring 48 wobbles relative to the shaft portion 80, the O-ring 48 and the shaft portion 80 will collide with each other, potentially causing wear of the O-ring 48 (or the shaft portion 80). According to the above structure, since no clearance is generated between the O-ring 48 and the shaft portion 80, wobble of the O-ring 48 relative to the shaft portion 80 can be suppressed. Therefore, wear of the O-ring 48 (or the shaft portion 80) can be suppressed.

[0102] In one or more embodiments, the O-ring 48 may be obscured by the locking plate 46 when viewed from the base end side of the shaft portion 80.

[0103] If the O-ring 48 is not covered by the locking plate 46 when viewed from the base end side of the shaft 80, the appearance of the pruning shears 2 may be impaired. According to the above structure, since the O-ring 48 is covered by the locking plate 46 when viewed from the base end side of the shaft 80, the appearance of the pruning shears 2 can be improved.

Claims

1. A cutting tool, wherein, The cutting tool includes: The first cut; The second cutter is capable of rotating relative to the first cutter; A base component that supports the first blade and the second blade; A threaded member comprising a head and a shaft extending from the head as a base end and having an external thread, wherein the first cutter and the base member are fastened together by threading the external thread with an internal thread. A loosening inhibition member, mounted on the shaft portion of the threaded member, inhibits loosening of the threaded member by being pressed by the head; and A detachment inhibition member is mounted adjacent to the loosening inhibition member on the shaft portion of the threaded member at a position closer to the top end of the shaft portion than the loosening inhibition member, thereby preventing the loosening inhibition member from moving from the base end side of the shaft portion toward the top end side and detaching from the threaded member. The shedding inhibition member is mounted on the shaft portion in a state where the shaft portion expands radially on the shaft portion.

2. The cutting tool according to claim 1, wherein, The loosening inhibition component includes: The first surface, facing the base end side of the shaft portion; and The second side faces the top end of the shaft portion. The shape of the first surface when viewed from the base end of the shaft is different from the shape of the second surface when viewed from the top end of the shaft.

3. The cutting tool according to claim 1 or 2, wherein, The loosening inhibition component includes: The plate portion extends along a generally frustum-shaped path that widens towards the top end of the shaft portion; and Multiple teeth are provided along at least one of the inner and outer circumferences of the plate portion and protrude in a direction extending toward the plate portion. The shedding inhibition member is a roughly annular elastic member.

4. The cutting tool according to claim 1 or 2, wherein, The first blade or the base component includes: A through hole through which the shaft portion passes; Abutment surface, which is abutted by the loosening inhibition member; and A recess is provided along the periphery of the through hole, such that at least a portion of the detachment inhibition member is retracted to a position further inward than the abutment surface.

5. The cutting tool according to claim 4, wherein, The recess is smoothly connected to the contact surface.

6. The cutting tool according to claim 1 or 2, wherein, The cutting tool includes: The motor shaft, which is connected to the second cutter; and An electric motor that rotates the motor shaft. The cutting action is performed by driving the electric motor to make the first blade and the second blade rotate relative to each other.

7. The cutting tool according to claim 1 or 2, wherein, When viewed from the base end side of the shaft, the detachment inhibition member is obscured by the loosening inhibition member.

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