Grounding body and grass cutter equipped with grounding body

Abstract

To provide a new and useful structure for a ground contact body attached to a cutting blade shaft of a mower.SOLUTION: A ground contact body is attached to a cutting blade shaft of a mower. The ground contact body comprises: an attachment part for attaching the ground contact body to the cutting blade shaft of the mower; and a main body part connected to the attachment part and brought into contact with the ground. In the cutting blade shaft, a cutting blade is attached above the ground contact body. The main body part has a first main body part made of a first resin, and a second main body part made of a second resin different from the first resin.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The technology disclosed in this specification relates to a ground contact body and a grass cutter equipped with the ground contact body. [Background technology]

[0002] Patent Document 1 discloses a grounding body. This grounding body includes an attachment part for attaching the grounding body to a blade shaft of a grass cutter, and a main body part that is connected to the attachment part and comes into contact with the ground. The main body part is made of one type of resin. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2008-35731 A Summary of the Invention [Problem to be solved by the invention]

[0004] The main body of the grounding body in Patent Document 1 is made of one type of resin. When the main body is made of one type of resin, it is difficult to improve the visibility for the user and the quietness of the grass cutter to which the grounding body is attached.

[0005] Provided herein is a novel and useful construction for a ground contact body attached to a blade shaft of a grass cutter. [Means for solving the problem]

[0006] This specification discloses a grounding body that is attached to a blade shaft of a grass cutter. The grounding body includes an attachment part for attaching the grounding body to the blade shaft, where a blade is attached to the blade shaft above the grounding body, and a main body part that is connected to the attachment part and comes into contact with the ground, and the main body part may have a first main body part made of a first resin and a second main body part made of a second resin different from the first resin.

[0007] According to the above configuration, the main body has a first main body made of a first resin and a second main body made of a second resin. By configuring the main body from two types of resin, it is possible to improve the visibility for the user and the quietness of the grass cutter, compared to a case where the main body is configured from one type of resin. Here, the resin in this specification is a concept that includes not only plastics with a relatively high hardness, but also thermosetting or thermoplastic elastomers and rubbers with lower hardness.

[0008] This specification also discloses a grass cutter comprising an operating rod, a blade shaft provided at a front portion of the operating rod, a blade attached to the blade shaft, and a grounding body attached to the blade shaft below the blade and grounded to the ground, the grounding body comprising an attachment portion for attaching the grounding body to the blade shaft and a main body portion connected to the attachment portion and grounded to the ground, the main body portion having a first main body portion made of a first resin and a second main body portion made of a second resin different from the first resin.

[0009] According to the above configuration, the main body of the grounding body has a first main body made of a first resin and a second main body made of a second resin. By configuring the main body from two types of resin, it is possible to improve the visibility for the user and improve the quietness of the grass cutter, compared to when the main body is configured from one type of resin. [Brief description of the drawings]

[0010] [Figure 1] FIG. 2 is a right side view of the grass cutter 2 of the first embodiment as viewed from the right. [Diagram 2] 2 is a right cross-sectional view of the grounding body 46 of the first embodiment. FIG. [Diagram 3] 1 is a perspective view of a grounding member 46 of the first embodiment as viewed from the upper right front. [Figure 4] FIG. 2 is a top view of the grounding body 46 of the first embodiment as viewed from above. [Diagram 5] FIG. 11 is a right cross-sectional view of the grounding body 246 of the second embodiment. [Figure 6] FIG. 11 is a right cross-sectional view of a grounding body 346 according to the third embodiment. [Figure 7] FIG. 13 is a right cross-sectional view of a grounding body 446 of the fourth embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] Representative and non-limiting examples 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. Additionally, the additional features and inventions disclosed may be used separately or together with other features and inventions to provide further improved grounding bodies.

[0012] In addition, the combinations of features and steps disclosed in the following detailed description are not essential for implementing the present invention in the broadest sense, but are specifically described only to illustrate representative embodiments of the present invention. Furthermore, the various features of the following representative embodiments and the various features described in the claims do not have to be combined in the exact manner of the embodiments described herein or in the order listed in order to provide additional and useful embodiments of the present invention.

[0013] All features described in the 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.

[0014] In one or more embodiments, the grounding body includes an attachment portion for attaching the grounding body to a blade shaft of a grass cutter, the blade being attached to the blade shaft above the grounding body, and a main body portion connected to the attachment portion and in contact with the ground, the main body portion having a first main body portion made of a first resin and a second main body portion made of a second resin different from the first resin.

[0015] In one or more embodiments, the grounding body may be attached to the blade shaft by a nut member. The attachment portion has a through hole through which the blade shaft passes, and the first resin and the second resin may be different in color. The lower end of the second body portion may be located lower than the lower end of the blade shaft and the lower end of the nut member, and the lower end of the first body portion may be located lower than the lower end of the second body portion.

[0016] When the grass cutter is used, the main body part that comes into contact with the ground wears out. As the main body part wears out, the blade shaft or the nut member comes into contact with the ground. In particular, when the outer peripheral surface of the nut member wears out, it becomes difficult to remove the nut member using a tool. That is, it becomes difficult to replace the grounding body or the blade. For this reason, it is desirable to replace the grounding body before the blade shaft or the nut member comes into contact with the ground. According to the above configuration, the lower end of the second main body part is located lower than the lower end of the blade shaft and the lower end of the nut member, and the lower end of the first main body part is located lower than the lower end of the second main body part. In addition, the first resin and the second resin are different in color. Therefore, when the first main body part wears out and the second main body part is exposed, the user can easily grasp the boundary between the first main body part and the second main body part. Therefore, the user can replace the grounding body at the time when the lower end of the second main body part is exposed, that is, before the blade shaft or the nut member comes into contact with the ground. As a result, wear of the blade shaft and the nut member can be suppressed.

[0017] In one or more embodiments, the outer periphery of the first body portion may contact the ground, and the second body portion may be disposed on an inner periphery of the first body portion.

[0018] According to the above configuration, when the first body part wears down, the second body part provided on the inner circumferential surface of the first body part becomes exposed before the cutting blade shaft or the nut member touches the ground. With this configuration, the user can prevent the cutting blade shaft and the nut member from wearing down by replacing the ground contact body when the exposed second body part becomes visible.

[0019] In one or more embodiments, a recess is provided on the inner surface of the first main body portion, and a lower end of the recess is located lower than the lower end of the blade shaft and the lower end of the nut member, and a second main body portion may be provided within the recess.

[0020] According to the above configuration, when the first body part wears down, the second body part provided in the recess on the inner circumferential surface of the first body part becomes exposed before the cutting blade shaft and the nut member contact the ground. With this configuration, the user can prevent the cutting blade shaft and the nut member from wearing down by replacing the ground contact body when the exposed second body part becomes visible.

[0021] In one or more embodiments, the first body portion may have a second body portion disposed on an upper surface thereof.

[0022] According to the above configuration, when the first body part wears down, the boundary between the first body part and the second body part disappears before the cutting blade shaft and the nut member contact the ground. According to this configuration, when the boundary between the first body part and the second body part becomes unrecognizable, the user replaces the ground contact body. Therefore, it is possible to prevent the outer circumferential surface of the fastening member from wearing down.

[0023] In one or more embodiments, the main body may further include a third main body made of a third resin different from the first resin and the second resin. The material of the third resin may be different from the material of the first resin and the material of the second resin. The third resin may be more elastically deformable than the first resin and the second resin. The third main body may abut against the lower surface of the cutting blade.

[0024] Generally, the body made of resin abuts, i.e., is in contact with, the underside of the blade made of metal. In this case, when the blade rotates, metallic noise is generated due to the contact between the body of the grounding body and the blade. By bringing a member made of a resin that is relatively easy to elastically deform into contact with the underside of the blade, the generation of metallic noise can be suppressed more than in a configuration in which a member made of a resin that is relatively difficult to elastically deform into contact with the underside of the blade. According to the above configuration, the third body made of a third resin that is more easily elastically deformed than the first resin and the second resin abuts against the underside of the blade. Therefore, metallic noise generated when the grass cutter is operating can be suppressed. As a result, the quietness of the grass cutter can be improved.

[0025] In one or more embodiments, the first body portion may include a cylindrical portion coupled to the mounting portion and a flange portion extending radially outward from a lower end of the cylindrical portion. The third body portion may be provided on an upper surface of the flange portion.

[0026] According to the above-mentioned configuration, it is possible to prevent the upper surface of the flange portion made of the first resin from contacting the lower surface of the cutting blade. That is, it is possible to more reliably prevent the first main body portion made of the first resin from contacting the lower surface of the cutting blade. Therefore, it is possible to more reliably suppress the metallic sound generated when the cutting blade is rotating.

[0027] In one or more embodiments, the third body portion may be configured separately from the first body portion and the second body portion. A recess having a downwardly recessed shape may be provided on the upper surface of the flange portion. The third body portion may be provided in the recess. An upper end of the third body portion may be located above an upper end of the flange portion.

[0028] When the third body part is configured separately from the first body part and the second body part, in order to bring the third body part into contact with the lower surface of the blade, the third body part needs to be placed on the upper surface of the flange part. In this case, in order to prevent the third body part from moving away from the upper surface of the flange part while the blade is rotating, the third body part needs to be fixed to the upper surface of the flange part by bonding, welding, or the like. According to the above configuration, the third body part is placed in a recessed part provided on the upper surface of the flange part. In this case, even if the third body part is not fixed to the upper surface of the flange part by bonding, welding, or the like, it is possible to prevent the third body part from moving away from the upper surface of the flange part while the blade is rotating. Therefore, the structure of the body part can be simplified.

[0029] In one or more embodiments, the first resin and the second resin may be made of different materials. The second resin may be more elastically deformable than the first resin. The second body portion may abut against a lower surface of the blade.

[0030] According to the above configuration, the second body portion made of the second resin, which is more elastically deformable than the first resin, contacts the underside of the blade. This makes it possible to suppress metallic noises that are generated when the grass cutter is in operation. As a result, the quietness of the grass cutter can be improved.

[0031] In one or more embodiments, the first body portion may include a cylindrical portion coupled to the mounting portion and a flange portion extending radially outward from a lower end of the cylindrical portion, and the second body portion may be provided on an upper surface of the flange portion.

[0032] According to the above-mentioned configuration, it is possible to prevent the upper surface of the flange portion made of the first resin from contacting the lower surface of the cutting blade. That is, it is possible to more reliably prevent the first main body portion made of the first resin from contacting the lower surface of the cutting blade. Therefore, it is possible to more reliably suppress the metallic sound generated when the cutting blade is rotating.

[0033] In one or more embodiments, the second body portion may be disposed on an inner circumferential surface of the flange portion.

[0034] According to the above-mentioned configuration, the inner circumferential surface of the flange portion made of the first resin can be prevented from contacting the underside of the cutting blade. That is, the first main body portion made of the first resin can be more reliably prevented from contacting the underside of the cutting blade. Therefore, the metallic sound generated when the cutting blade is rotating can be more reliably suppressed.

[0035] In one or more embodiments, the second body portion may be configured separately from the first body portion. A recess having a downwardly recessed shape may be provided on the upper surface of the flange portion. The second body portion may be provided in the recess. An upper end of the second body portion may be located above an upper end of the flange portion.

[0036] When the second body part is configured separately from the first body part, in order to bring the second body part into contact with the lower surface of the blade, the second body part needs to be placed on the upper surface of the flange part. In this case, in order to prevent the second body part from moving away from the upper surface of the flange part while the blade is rotating, the second body part needs to be fixed to the upper surface of the flange part by bonding, welding, or the like. According to the above configuration, the second body part is placed in a recessed part provided on the upper surface of the flange part. In this case, even if the second body part is not fixed to the upper surface of the flange part by bonding, welding, or the like, it is possible to prevent the second body part from moving away from the upper surface of the flange part while the blade is rotating. Therefore, the structure of the body part can be simplified.

[0037] (First embodiment) A grass cutter 2 of a first embodiment will be described with reference to Figures 1 to 3. As shown in Figure 1, the grass cutter 2 includes a cutting blade unit 10, an operating rod 12, and a rear housing 14. In the following, the direction perpendicular to the ground P1 in Figure 1 will be referred to as the up-down direction, the direction perpendicular to the up-down direction in Figure 1 will be referred to as the front-rear direction, and the direction perpendicular to the up-down direction and the front-rear direction will be referred to as the left-right direction.

[0038] The cutting blade unit 10 is provided on a front portion 12a of the operating rod 12, and a rear housing 14 is provided on a rear portion 12b of the operating rod 12. The operating rod 12 extends rearward and upward from the cutting blade unit 10. The operating rod 12 connects the cutting blade unit 10 and the rear housing 14.

[0039] The operating rod 12 has a hollow pipe shape and extends linearly. The operating rod 12 is provided with a loop handle 20 for a user to grip. A grip 22 is provided between the loop handle 20 of the operating rod 12 and the rear housing 14. The grip 22 is formed so as to cover the outer periphery of the operating rod 12. The grip 22 includes a lock-off lever 24 provided on the upper surface and a start switch 26 provided on the lower surface. The lock-off lever 24 is a lever for restricting and releasing the restriction of the pressing operation of the start switch 26. The start switch 26 is a switch for driving a motor (not shown) described later. When the start switch 26 is not pressed, the supply of power to the motor is cut off. When the start switch 26 is pressed, power is supplied to the motor. When the lock-off lever 24 is not pressed, the pressing operation of the start switch 26 is restricted. When the lock-off lever 24 is pressed in, the restriction on pressing the start switch 26 is released. A transmission shaft 28 (see FIG. 2) that is rotated by the drive of the motor is rotatably housed inside the operating rod 12.

[0040] The rear housing 14 accommodates a motor (not shown) and a control board (not shown). The motor may be a brushless DC motor, a brushed DC motor, or another type of motor such as an AC motor. In a modified example, an engine may be accommodated in the rear housing 14. The control board controls the operation of the motor. One end of a power wiring 30 is connected to the rear of the rear housing 14. A connector 32 is provided at the other end of the power wiring 30. A power wiring extending from an external power source such as a battery (not shown) is connected to the connector 32. The motor is operated by power supplied via the power wiring 30.

[0041] As shown in FIG. 1 and FIG. 2, the blade unit 10 includes a gear housing 40, a safety cover 42, a blade 44, and a grounding member 46. The blade 44 is a two-blade blade consisting of a cutting edge extending forward and a cutting edge extending backward. The blade 44 is a metal blade. In a modified example, the blade 44 may be a four-blade, eight-blade, or disk-shaped chip saw. In another modified example, the blade 44 may be a nylon cord. As shown in FIG. 2, an insertion hole 40a is provided at the upper rear part of the gear housing 40 for inserting the front part 12a of the operating rod 12. The gear housing 40 accommodates a first gear 48, a second gear 50, and a blade shaft 52. The first gear 48 is attached to the transmission shaft 28. The second gear 50 is attached to the blade shaft 52. The first gear 48 is engaged with the second gear 50. The first gear 48 and the second gear 50 are bevel gears.

[0042] An opening 40b is provided at the bottom of the gear housing 40. The blade unit 10 further includes a transmission part 54, an upper metal fitting 56, a lower metal fitting 58, and a nut member 60. The transmission part 54 is provided at the opening 40b. The transmission part 54 includes a cylindrical part 54a and a disk part 54b extending radially outward from the cylindrical part 54a. The cylindrical part 54a of the transmission part 54 is detachably attached to the blade shaft 52. The upper metal fitting 56 is provided on the lower surface side of the disk part 54b of the transmission part 54. The blade 44 is provided on the lower surface side of the upper metal fitting 56. The lower metal fitting 58 is provided on the lower surface side of the blade 44. The nut member 60 engages with a threaded part 52a formed at the bottom of the blade shaft 52. An attachment part 70 of the grounding body 46, which will be described later, is provided between the nut member 60 and the lower metal fitting 58. The lower end 52b of the blade shaft 52 is located below the lower end 60a of the nut member 60. By tightening the nut member 60, the blade 44 is clamped between the upper metal fitting 56 and the lower metal fitting 58. In this state, when the blade shaft 52 rotates, the transmission part 54, the upper metal fitting 56, the lower metal fitting 58, the nut member 60, the grounding body 46, and the blade 44 rotate integrally.

[0043] Next, the grounding body 46 will be described with reference to Figs. 1 to 4. The grounding body 46 includes an attachment portion 70 and a main body portion 72. The attachment portion 70 includes a disk portion 74 and a connecting portion 76. The disk portion 74 has a central portion that protrudes upward. A through hole 74a is provided in the central portion of the disk portion 74. The disk portion 74 is provided between the lower metal fitting 58 and the nut member 60. The connecting portion 76 is connected to the main body portion 72.

[0044] Next, the main body 72 will be described. The grounding body 46 of this embodiment is formed by two-color molding. The main body 72 is made of a first resin having a first color and a second resin having a second color. The first color and the second color are not particularly limited, but for example, the first color is "black" and the second color is "gray". The material of the first resin and the material of the second resin may be the same or different. In Figs. 2 to 4, in order to clearly show the difference between the color of the first resin and the color of the second resin, the part made of the first resin having the first color is shown in "white" and the part made of the second resin having the second color is shown in "gray". In the following, the overall shape of the main body 72 will be described, and then the part made of the first resin and the part made of the second resin will be described.

[0045] As shown in FIG. 3 and FIG. 4, the main body 72 includes an inner cylindrical portion 80, a flange portion 82, and six rib portions 84. As shown in FIG. 2, the inner diameter of the inner cylindrical portion 80 is larger than the outer diameter of the nut member 60. The connecting portion 76 of the mounting portion 70 is connected to the upper portion of the inner cylindrical portion 80. The flange portion 82 includes a curved portion 86 extending radially outward from the lower end of the inner cylindrical portion 80, and an outer cylindrical portion 88 extending upward from the outer peripheral end of the curved portion 86. The curved portion 86 is curved so as to extend from the bottom to the top as it extends radially outward. The upper surface of the outer cylindrical portion 88 abuts against the lower surface of the cutting blade 44. As shown in FIG. 3, the rib portion 84 includes an inner rib portion 90 and an outer rib portion 92. The inner rib portion 90 extends radially outward from the outer peripheral surface of the inner cylindrical portion 80. The height of the upper surface of the inner rib portion 90 is the same as the height of the upper surface of the inner cylindrical portion 80. The outer rib portion 92 extends radially outward from the radially outer end of the inner rib portion 90. The outer rib portion 92 is connected to the inner circumferential surface of the outer cylindrical portion 88. The height of the upper surface of the outer rib portion 92 is the same as the height of the upper surface of the outer cylindrical portion 88.

[0046] Next, the portion of the main body 72 made of the first resin and the portion made of the second resin will be described. Hereinafter, the portion made of the first resin and the portion made of the second resin will be referred to as the "first main body 78" and the "second main body 79", respectively. As shown in FIG. 2, the portion of the main body 72 below a plane P2 including the front-rear and left-right directions is the first main body 78, and the portion of the main body 72 above the plane P2 is the second main body 79. The plane P2 is a plane located a distance D below the lower end 52b of the blade shaft 52 in the up-down direction.

[0047] As shown in FIG. 2, the inner cylindrical portion 80 is composed of a first inner cylindrical portion 80a, which is a portion below the plane P2, and a second inner cylindrical portion 80b, which is a portion above the plane P2. Therefore, the first inner cylindrical portion 80a is made of a first resin, and the second inner cylindrical portion 80b is made of a second resin. The curved portion 86 of the flange portion 82 is composed of a first curved portion 86a, which is a portion below the plane P2, and a second curved portion 86b, which is a portion above the plane P2. Therefore, the first curved portion 86a is made of a first resin, and the second curved portion 86b is made of a second resin. The outer cylindrical portion 88 of the flange portion 82 is provided above the plane P2. Therefore, the outer cylindrical portion 88 is made only of the second resin. The inner rib portion 90 is composed of a first inner rib portion 90a, which is a portion below the plane P2, and a second inner rib portion 90b, which is a portion above the plane P2. Therefore, the first inner rib portion 90a is made of a first resin, and the second inner rib portion 90b is made of a second resin. The outer rib portion 92 is composed of a first outer rib portion 92a, which is a portion below the plane P2, and a second outer rib portion 92b, which is a portion above the plane P2. Therefore, the first outer rib portion 92a is made of a first resin, and the second outer rib portion 92b is made of a second resin. Therefore, the first main body portion 78 is composed of the first inner cylindrical portion 80a, the first curved portion 86a, the first inner rib portion 90a, and the first outer rib portion 92a. The second main body portion 79 is composed of a second inner cylindrical portion 80b, a second curved portion 86b, an outer cylindrical portion 88, a second inner rib portion 90b, and a second outer rib portion 92b. Thus, in this embodiment, the second main body portion 79 is provided on the upper surface of the first main body portion 78. The lower end 79a of the second main body portion 79 is provided below the lower end 52b of the blade shaft 52 and the lower end 60a of the nut member 60. The lower end 78a of the first main body portion 78 is provided below the lower end 79a of the second main body portion 79.

[0048] In one or more embodiments, the grounding body 46 includes an attachment portion 70 for attaching the grounding body 46 to the blade shaft 52, and a main body portion 72 that is connected to the attachment portion 70 and grounded to the ground P1, as shown in Figs. 1 and 2. The blade 44 is attached to the blade shaft 52 above the grounding body 46. The main body portion 72 has a first main body portion 78 made of a first resin, and a second main body portion 79 made of a second resin different from the first resin. By forming the main body portion 72 from two types of resin, it is possible to improve the visibility of the user and to improve the quietness of the grass cutter 2, compared to when the main body portion 72 is made of one type of resin.

[0049] In one or more embodiments, the grounding body 46 is attached to the blade shaft 52 by the nut member 60 as shown in FIG. 2. The attachment portion 70 has a through hole 74a through which the blade shaft 52 passes. The first resin and the second resin have different colors. The lower end 79a of the second body portion 79 is located lower than the lower end 52b of the blade shaft 52 and the lower end 60a of the nut member 60, and the lower end 78a of the first body portion 78 is located lower than the lower end 79a of the second body portion 79. When the grass cutter 2 is used, the body portion 72 of the grounding body 46 that comes into contact with the ground P1 wears away. As the body portion 72 wears away, the blade shaft 52 or the nut member 60 comes into contact with the ground P1. In particular, when the outer circumferential surface of the nut member 60 wears away, it becomes difficult to remove the nut member 60 using a tool. That is, it becomes difficult to easily replace the grounding body 46 or the blade 44. Therefore, it is desirable to replace the grounding body 46 before the blade shaft 52 or the nut member 60 comes into contact with the ground P1. According to the above configuration, the lower end 79a of the second main body portion 79 is located lower than the lower end 52b of the blade shaft 52 and the lower end 60a of the nut member 60, and the lower end 78a of the first main body portion 78 is located lower than the lower end 79a of the second main body portion 79. In addition, the color of the first resin is different from the color of the second resin. Therefore, when the first main body portion 78 wears down and the second main body portion 79 is exposed, the user can easily grasp the boundary between the first main body portion 78 and the second main body portion 79. Therefore, the user can replace the grounding body 46 at the time when the lower end 79a of the second main body portion 79 is exposed, that is, before the blade shaft 52 or the nut member 60 comes into contact with the ground P1. As a result, it is possible to suppress the outer circumferential surface of the nut member 60 from wearing down.

[0050] In one or more embodiments, as shown in FIG. 2, a second body portion 79 is provided on the upper surface of the first body portion 78. According to the above configuration, the first body portion 78 is worn down to the upper surface of the first body portion 78, and the boundary between the first body portion 78 and the second body portion 79 disappears. According to such a configuration, the user replaces the grounding body 46 when the boundary between the first body portion 78 and the second body portion 79 becomes unrecognizable. Therefore, it is possible to suppress the outer circumferential surface of the nut member 60 from wearing down.

[0051] In one or more embodiments, as shown in Figs. 1 to 4, the grass cutter 2 includes an operating rod 12, a blade shaft 52 provided on a front portion 12a of the operating rod 12, a blade 44 attached to the blade shaft 52, and a grounding body 46 attached to the blade shaft 52 below the blade 44 and grounded to the ground P1. The grounding body 46 includes an attachment portion 70 for attaching the grounding body 46 to the blade shaft 52, and a main body portion 72 connected to the attachment portion 70 and grounded to the ground P1. The main body portion 72 includes a first main body portion 78 made of a first resin and a second main body portion 79 made of a second resin different from the first resin. By forming the main body portion 72 of the grounding body 46 from two types of resin, it is possible to improve the visibility of the user and improve the quietness of the grass cutter 2 compared to a case in which the main body portion 72 is made of one type of resin.

[0052] (Second Example) Next, a grounding body 246 of the second embodiment will be described with reference to Fig. 5. Note that components common to the embodiments will be given the same reference numerals and descriptions thereof will be omitted.

[0053] As shown in Fig. 5, the grounding body 246 includes an attachment portion 70 and a main body portion 272. Like the main body portion 72 of the first embodiment, the main body portion 272 of the present embodiment is formed by two-color molding. That is, the main body portion 272 is made of a first resin having a first color and a second resin having a second color. The main body portion 272 includes a first main body portion 278 made of the first resin and a second main body portion 279 made of the second resin.

[0054] The first main body portion 278 includes an inner cylindrical portion 280 and a flange portion 282. The shape of the inner cylindrical portion 280 is the same as that of the inner cylindrical portion 80 (see FIG. 2) of the first embodiment. The flange portion 282 includes a curved portion 286 extending radially outward from the lower end of the inner cylindrical portion 280, and an outer cylindrical portion 288 extending upward from the outer peripheral end of the curved portion 286. The shape of the outer cylindrical portion 288 is the same as that of the outer cylindrical portion 88 (see FIG. 2) of the first embodiment. The outer shape of the curved portion 286 is the same as that of the curved portion 86 (see FIG. 2) of the first embodiment. The upper portion of the curved portion 286 is provided with a recess 290 recessed downward. A lower end 290a of the recess 290 is located lower than the lower end 52b of the blade shaft 52 and the lower end 60a of the nut member 60.

[0055] The second main body portion 279 is provided on the inner circumferential surface of the first main body portion 278 (more specifically, the outer circumferential surface of the inner cylindrical portion 280, the upper surface of the curved portion 286, and the inner circumferential surface of the outer cylindrical portion 288). The second main body portion 279 is also provided in a recess 290 provided in an upper portion of the curved portion 286. The lower end 279a of the second main body portion 279 is located lower than the lower end 52b of the blade shaft 52 and the lower end 60a of the nut member 60. The lower end 278a of the first main body portion 278 is provided lower than the lower end 279a of the second main body portion 279.

[0056] In one or more embodiments, as shown in FIG. 5, the outer peripheral surface of the flange portion 282 of the first body portion 278 contacts the ground P1, and the second body portion 279 is provided on the inner peripheral surface of the flange portion 282 of the first body portion 278 (i.e., the upper surface of the curved portion 286 and the inner peripheral surface of the outer cylindrical portion 288). According to the above configuration, when the first body portion 278 wears down, the second body portion 279 provided on the inner peripheral surface of the first body portion 278 is exposed before the cutting blade shaft 52 or the nut member 60 contacts the ground P1. According to such a configuration, the user can replace the grounding body 246 at the time when the exposed second body portion 279 becomes visible, thereby suppressing the outer peripheral surface of the nut member 60 from wearing down.

[0057] In one or more embodiments, as shown in FIG. 5, a recess 290 is provided on the inner circumferential surface of the flange portion 282 of the first main body portion 278 (specifically, the upper surface of the curved portion 286). A lower end 290a of the recess 290 is located lower than the lower end 52b of the blade shaft 52 and the lower end 60a of the nut member 60. A second main body portion 279 is provided in the recess 290. According to the above configuration, the second main body portion 279 provided in the recess 290 is exposed as the first main body portion 278 wears down. According to such a configuration, the user can replace the grounding body 246 when the exposed second main body portion 279 becomes visible, thereby suppressing wear of the outer circumferential surface of the nut member 60.

[0058] (Third Example) Next, referring to FIG. 6, a grounding body 346 of a third embodiment will be described. The grounding body 346 includes an attachment portion 70 and a main body portion 372. The main body portion 372 of this embodiment is also formed by two-color molding. In this embodiment, the main body portion 372 is composed of a first main body portion 378 made of a first resin and a second main body portion 379 made of a second resin. The second resin is more easily elastically deformed than the first resin. For example, the Young's modulus of the second resin (i.e., the second main body portion 379) is smaller than the Young's modulus of the first resin (i.e., the first main body portion 378). The first resin is, for example, a resin made of PA6, and the second resin is, for example, a resin made of thermoplastic polyurethane (TPU, urethane resin).

[0059] The first main body portion 378 includes an inner cylindrical portion 380 and a flange portion 382. The shape of the inner cylindrical portion 380 is the same as the shape of the inner cylindrical portion 80 (see FIG. 2) of the first embodiment. The flange portion 382 includes a curved portion 386 extending radially outward from the lower end of the inner cylindrical portion 380, and an outer cylindrical portion 388 extending upward from the outer peripheral end of the curved portion 386. The outer cylindrical portion 388 extends upward from the outer peripheral end of the curved portion 386. The upper surface of the outer cylindrical portion 388 does not abut against the lower surface of the cutting blade 44. The outer shape of the curved portion 386 is the same as the outer shape of the curved portion 86 (see FIG. 2) of the first embodiment. The upper end 386a of the curved portion 386 is located lower than the lower end 52b of the cutting blade shaft 52 and the lower end 60a of the nut member 60.

[0060] The second main body portion 379 is provided on the outer circumferential surface of the inner cylindrical portion 380, the upper surface of the curved portion 386, the inner circumferential surface of the outer cylindrical portion 388, and the upper surface of the outer cylindrical portion 388. The upper surface of the second main body portion 379 abuts against the lower surface of the cutting blade 44. Furthermore, the lower end 379a of the second main body portion 379 is located lower than the lower end 52b of the cutting blade shaft 52 and the lower end 60a of the nut member 60. Furthermore, the lower end 378a of the first main body portion 378 is provided lower than the lower end 379a of the second main body portion 379.

[0061] In one or more embodiments, the material of the first resin is different from the material of the second resin, and the second resin is more easily elastically deformed than the first resin. As shown in FIG. 6, the second body portion 379 abuts against the lower surface of the cutting blade 44. By bringing a member made of a resin that is relatively easily elastically deformed into contact with the lower surface of the cutting blade 44, the generation of metallic sounds can be suppressed more than in a configuration in which a member made of a resin that is relatively less easily elastically deformed is in contact with the lower surface of the cutting blade 44. According to the above configuration, the second body portion 379 made of the second resin that is relatively easily elastically deformed abuts against the lower surface of the cutting blade 44. Therefore, metallic sounds generated when the grass cutter 2 is operating can be suppressed. As a result, the quietness of the grass cutter 2 can be improved. From the viewpoint of suppressing metallic sounds, the second body portion 379 only needs to abut at least the lower surface of the cutting blade 44, and does not need to have a portion along the lower end 379a and the outer cylindrical portion 388.

[0062] In one or more embodiments, as shown in FIG. 6, the first body portion 378 includes an inner cylindrical portion 380 connected to the attachment portion 70, and a flange portion 382 extending radially outward from a lower end of the inner cylindrical portion 380. The second body portion 379 is provided on the upper surface of the flange portion 382. With the above configuration, it is possible to prevent the upper surface of the flange portion 382 made of the first resin from contacting the lower surface of the cutting blade 44. That is, it is possible to more reliably prevent the first body portion 378 made of the first resin from contacting the lower surface of the cutting blade 44. Therefore, it is possible to more reliably suppress the metallic sound generated when the cutting blade 44 is rotating.

[0063] In one or more embodiments, second main body portion 379 is provided on the inner circumferential surface of flange portion 382, ​​as shown in Fig. 6. With the above configuration, it is possible to prevent the inner circumferential surface of flange portion 382 made of the first resin from abutting against the underside of cutting blade 44. In other words, it is possible to more reliably prevent first main body portion 378 made of the first resin from abutting against the underside of cutting blade 44. Therefore, it is possible to more reliably suppress the metallic sound generated when cutting blade 44 is rotating.

[0064] (Correspondence) Inner cylindrical portion 380 is an example of a "cylindrical portion."

[0065] (Fourth Example) Next, the grounding body 446 of the fourth embodiment will be described with reference to FIG. 7. The grounding body 446 includes an attachment portion 70 and a main body portion 472. The main body portion 472 includes a grounding portion 474 that is grounded to the ground P1, an inner main body portion 476, and an abutment portion 478. The grounding portion 474 and the inner main body portion 476 are integrally formed. The grounding portion 474 and the inner main body portion 476 are formed by two-color molding. The abutment portion 478 is formed separately from the grounding portion 474 and the inner main body portion 476. The abutment portion 478 is, for example, a rubber O-ring, and is made of a resin that is more easily elastically deformed than the grounding portion 474 and the inner main body portion 476. For example, the Young's modulus of the abutment portion 478 is smaller than the Young's modulus of the grounding portion 474 and the inner main body portion 476.

[0066] The grounding portion 474 includes an inner cylindrical portion 480 and a flange portion 482. The shape of the inner cylindrical portion 480 is the same as that of the inner cylindrical portion 280 of the second embodiment (see FIG. 5). The flange portion 482 includes a curved portion 486 extending radially outward from the lower end of the inner cylindrical portion 480, and an outer cylindrical portion 488 extending upward from the outer peripheral end of the curved portion 486. The shape of the curved portion 486 is the same as that of the curved portion 286 of the second embodiment (see FIG. 5). The upper portion of the curved portion 486 is provided with a first recess 490 recessed downward. The lower end 490a of the first recess 490 is located lower than the lower end 52b of the blade shaft 52 and the lower end 60a of the nut member 60. The upper surface of the outer cylindrical portion 488 is provided with a second recess 492 recessed downward. The second recess 492 is provided with the abutment portion 478. The upper end of the abutment portion 478 is located higher than the upper end of the outer cylindrical portion 488. When the grounding body 446 is attached to the blade shaft 52, a gap S1 is provided between the upper end of the outer cylindrical portion 488 and the lower surface of the blade 44. The upper end of the abutment portion 478 is in contact with the lower surface of the blade 44.

[0067] The shape of the inner main body portion 476 is the same as that of the second main body portion 279 (see FIG. 5) of the second embodiment. The inner main body portion 476 is provided on the inner circumferential surface of the ground contact portion 474 (specifically, the outer circumferential surface of the inner cylindrical portion 480, the upper surface of the curved portion 486, and the inner circumferential surface of the outer cylindrical portion 488). The inner main body portion 476 is also provided in the first recess 490. The lower end 476a of the inner main body portion 476 is located lower than the lower end 52b of the blade shaft 52 and the lower end 60a of the nut member 60. The lower end 474a of the ground contact portion 474 is provided lower than the lower end 476a of the inner main body portion 476.

[0068] In one or more embodiments, the body 472 includes a grounding portion 474 (an example of a "first body"), an inner body 476 (an example of a "second body"), and an abutment portion 478 (an example of a "third body"). The material of the abutment portion 478 is different from the material of the grounding portion 474 and the inner body 476. The abutment portion 478 is more easily elastically deformed than the grounding portion 474 and the inner body 476. The abutment portion 478 abuts against the lower surface of the cutting blade 44. According to the above configuration, the abutment portion 478 made of the third resin, which is more easily elastically deformed than the grounding portion 474 and the inner body 476, abuts against the lower surface of the cutting blade 44. Therefore, metallic sounds generated when the grass cutter 2 is operating can be suppressed. As a result, the quietness of the grass cutter 2 can be improved.

[0069] In one or more embodiments, ground contact portion 474 includes inner cylindrical portion 480 (one example of a "cylindrical portion") and flange portion 482. Contact portion 478 is provided on the upper surface of flange portion 482. With the above configuration, it is possible to prevent the upper surface of flange portion 482 made of the first resin from contacting the lower surface of blade 44. In other words, it is possible to more reliably prevent ground contact portion 474 made of the first resin from contacting the lower surface of blade 44. Therefore, it is possible to more reliably suppress metallic sounds generated when blade 44 is rotating.

[0070] In one or more embodiments, the grounding portion 474 is configured separately from the grounding portion 474 and the inner main body portion 476. The upper surface of the flange portion 482 is provided with a second recess 492 (an example of a "recessed portion") having a shape recessed downward. The grounding portion 474 is provided in the second recess 492. The upper end of the grounding portion 474 is located higher than the upper end of the flange portion 482. According to the above configuration, the grounding portion 474 is disposed in the second recess 492 provided in the upper surface of the flange portion 482. In this case, even if the grounding portion 474 is not fixed to the upper surface of the flange portion 482 by adhesion, welding, or the like, it is possible to prevent the grounding portion 474 from separating from the upper surface of the flange portion 482 while the cutting blade 44 is rotating. Therefore, the structure of the main body portion 472 can be simplified.

[0071] Although specific examples of the present invention have been described in detail above, these are merely examples and do not limit the scope of the claims. The technology described in the claims includes various modifications and changes of the specific examples exemplified above.

[0072] 5, the recess 290 does not have to be provided on the upper part of the curved part 286 of the first main body part 278. In this modification, the upper surface of the curved part 286 may be located lower than the lower end 52b of the blade shaft 52 and the lower end 60a of the nut member 60. As a result, the lower end 279a of the second main body part 279 provided on the inner circumferential surface of the flange part 282 (i.e., the outer circumferential surface of the inner cylindrical part 280, the upper surface of the curved part 286, and the inner circumferential surface of the outer cylindrical part 288) is located lower than the lower end 52b of the blade shaft 52 and the lower end 60a of the nut member 60.

[0073] 6, a second body portion 379 may have a flange portion instead of the first body portion 378. In this modification, the upper surface of the flange portion made of the second resin abuts against the lower surface of the cutting blade 44.

[0074] 6, the second main body portion 379 may be provided only on the upper surface of the flange portion 382 (specifically, the upper surface of the outer cylindrical portion 388). That is, the second main body portion 379 does not have to be provided on the inner circumferential surface of the flange portion 382 (specifically, the inner circumferential surface of the curved portion 386).

[0075] (Fourth Modification) The first body portion 78 and the second body portion 79 in the first embodiment shown in Figures 1 to 4 may be formed separately. Also, the first body portion 278 and the second body portion 279 in the second embodiment shown in Figure 5 may be formed separately. Also, the first body portion 378 and the second body portion 379 in the third embodiment shown in Figure 6 may be formed separately.

[0076] 7, the main body 472 includes a grounding portion 474 and an abutment portion 478, and may not include the inner main body 476. In this modification, the grounding portion 474 and the abutment portion 478 are examples of the "first main body" and the "second main body", respectively. With this configuration as well, it is possible to suppress metallic sounds generated when the grass cutter 2 is operating, and it is possible to improve the quietness of the grass cutter 2.

[0077] The technical elements described in this specification or drawings have technical utility either alone or in various combinations, and are not limited to the combinations described in the claims at the time of filing. In addition, the technologies illustrated in this specification or drawings can achieve multiple objectives simultaneously, and achieving one of these objectives is itself technically useful. [Explanation of symbols]

[0078] 2: Grass trimmer 10: Blade unit 12: Operating rod 12a: Front 12b: Rear 14: Rear housing 20: Loop handle 22: Grip 24: Lock-off lever 26: Start switch 28: Transmission shaft 30: Power wiring 32: Connector 40: Gear housing 40a: Insertion hole 40b:Aperture 42: Safety cover 44:Kariblade 46: Ground body 48: 1st gear 50: 2nd gear 52: Blade shaft 52a: Threaded part 52b: Bottom end 54: Transmission section 54a: Cylindrical part 54b: Disc section 56: Upper bracket 58: Lower bracket 60: Nut material 60a: Bottom end 70: Mounting part 72: Main body 74: Disc section 74a: Through hole 76:Connection part 78: First body part 78a: Bottom end 79: Second body part 79a: Bottom end 80: Inner cylindrical part 80a: First inner cylindrical portion 80b: second inner cylindrical portion 82: Flange part 84: Rib section 86: Curved section 86a: First curved section 86b: Second curved section 88: Outer cylindrical part 90: Inner rib 90b: Second inner rib 92: Outer rib 92b: Second outer rib 246: Ground body 272: Main body 278: First body part 278a: Bottom end 279: Second body part 279a: Bottom end 280: Inner cylindrical part 282: Flange part 286: Curved section 288: Outer cylindrical part 290: Recess 290a: Bottom end 346 :Grounding body 372: Main body 378: First body part 378a: bottom edge 379: Second body part 379a: bottom edge 380: Inner cylindrical part 382: Flange part 386: Curved section 386a :Top edge 388: Outer cylindrical part 446: Ground body 472: Main body 474: Grounding part 474a: Bottom end 476:Inner body part 476a: Bottom edge 478: Contact part 480: Inner cylindrical part 482: Flange part 486: Curved section 488: Outer cylindrical part 490: First recess 490a: Bottom end 492: Second recess

Claims

1. A grounding body attached to a blade shaft of a grass cutter, a mounting portion for mounting the grounding body to the blade shaft, the mounting portion being configured to mount the blade on the blade shaft above the grounding body; A main body portion connected to the mounting portion and adapted to be grounded; Equipped with The main body portion has a first main body portion made of a first resin and a second main body portion made of a second resin different from the first resin, The grounding body is attached to the blade shaft by a nut member, The attachment portion has a through hole through which the blade shaft passes, The first resin and the second resin have different colors, A lower end of the second main body portion is located lower than a lower end of the blade shaft and a lower end of the nut member, A lower end of the first body portion is located lower than the lower end of the second body portion. Grounding body.

2. The outer circumferential surface of the first main body is in contact with the ground, The grounding body according to claim 1 , wherein the second body portion is provided on an inner circumferential surface of the first body portion.

3. A recess is provided on the inner circumferential surface of the first main body portion, a lower end of the recess is located lower than the lower end of the blade shaft and the lower end of the nut member, The grounding body according to claim 2 , wherein the second body portion is provided within the recess.

4. The grounding body according to claim 1 , wherein the second body portion is provided on an upper surface of the first body portion.

5. the main body portion further includes a third main body portion made of a third resin different from the first resin and the second resin, a material of the third resin is different from a material of the first resin and a material of the second resin; The third resin is more easily elastically deformed than the first resin and the second resin, The grounding member according to claim 1 , wherein the third body portion abuts against a lower surface of the cutting blade.

6. The first main body portion includes a cylindrical portion connected to the mounting portion and a flange portion extending radially outward from a lower end of the cylindrical portion, The grounding body according to claim 5 , wherein the third body portion is provided on an upper surface of the flange portion.

7. The third body portion is configured separately from the first body portion and the second body portion, The flange portion has an upper surface provided with a recess having a downwardly recessed shape, The third main body portion is provided in the recessed portion, The grounding body according to claim 6 , wherein an upper end of the third body portion is located higher than an upper end of the flange portion.

8. A grounding body attached to a blade shaft of a grass cutter, a mounting portion for mounting the grounding body to the blade shaft, the mounting portion being configured to mount the blade on the blade shaft above the grounding body; A main body portion connected to the mounting portion and adapted to be grounded; Equipped with The main body portion has a first main body portion made of a first resin and a second main body portion made of a second resin different from the first resin, The first resin and the second resin are made of different materials, The second resin is more elastically deformable than the first resin, The second main body portion abuts against a lower surface of the cutting blade. Grounding body.

9. The first main body portion includes a cylindrical portion connected to the mounting portion and a flange portion extending radially outward from a lower end of the cylindrical portion, The grounding body according to claim 8 , wherein the second body portion is provided on an upper surface of the flange portion.

10. The grounding body according to claim 9 , wherein the second main body portion is provided on an inner circumferential surface of the flange portion.

11. The second body portion is configured separately from the first body portion, The flange portion has an upper surface provided with a recess having a downwardly recessed shape, The second main body portion is provided in the recessed portion, The grounding body according to claim 9 , wherein an upper end of the second body portion is located higher than an upper end of the flange portion.

12. An operating rod and A cutting blade shaft provided at a front portion of the operating rod; a cutting blade attached to the cutting blade shaft; a grounding body attached to the blade shaft below the blade and adapted to contact the ground, The grounding body is a mounting portion for mounting the grounding body to the blade shaft; A main body portion connected to the mounting portion and adapted to be grounded; Equipped with The main body portion has a first main body portion made of a first resin and a second main body portion made of a second resin different from the first resin, The grounding body is attached to the blade shaft by a nut member, The attachment portion has a through hole through which the blade shaft passes, The first resin and the second resin have different colors, A lower end of the second main body portion is located lower than a lower end of the blade shaft and a lower end of the nut member, A lower end of the first body portion is located lower than the lower end of the second body portion. Lawnmower.

13. An operating rod and A cutting blade shaft provided at a front portion of the operating rod; a cutting blade attached to the cutting blade shaft; a grounding body attached to the blade shaft below the blade and adapted to contact the ground, The grounding body is a mounting portion for mounting the grounding body to the blade shaft; A main body portion connected to the mounting portion and adapted to be grounded; Equipped with The main body portion has a first main body portion made of a first resin and a second main body portion made of a second resin different from the first resin, The first resin and the second resin are made of different materials, The second resin is more elastically deformable than the first resin, The second main body portion abuts against a lower surface of the cutting blade. Lawnmower.

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