Nylon cord cutter for brush cutters

Abstract

To provide a nylon cord cutter for a brush cutter, which allows easy winding work and quick fastening work. [Solution] This is a nylon cord cutter 1 for a brush cutter which allows the main body 2 and cover 3 to be attached and detached easily and quickly. The main body is formed with a drive shaft mounting hole 21 and a locking piece for fitting the cover so that it can be detached and attached freely. The inner outer peripheral edge of the main body is provided with a number of nylon cord locking pins. The cover has a large diameter flange 32 and a small diameter flange 33 around which the nylon cord is wound, which are provided on the outer periphery of a bottomed cylindrical trunk 31. A pair of nylon cord withdrawal grooves are formed on the circumferential edge of the large diameter flange, and a locking mechanism is provided for attaching and detaching the main body and cover.

Description

[Technical field]

[0001] This invention relates to a nylon cord cutter for a brush cutter used to cut down weeds, etc. [Background technology]

[0002] Conventionally, a rotating plate such as a disk that is detachably fixed to a rotating shaft, for example, a tipped saw, has been used. Instead, various techniques have been proposed for brush cutters that cut weeds by having a fixed length of nylon cord protrude from a disk-shaped main body and rotating the nylon cord as the disk rotates. The nylon cord is made of a relatively hard synthetic resin material and is attached so that a fixed length of the cord fits around the outer periphery of the disk and does not easily come off even when the disk is subjected to a strong centrifugal force.

[0003] One cord retention mechanism for the cord storage member of a corded brush cutter involves tying a knot at the end of the cord to prevent the cord from slipping out of the main body case. This mechanism involves holding the cord by hooking the center of the cord onto a hook provided on the outer surface of the cylindrical body of the cord storage member, and then winding and storing the cord in the cord storage member (see Patent Document 1). Also disclosed is a cord storage member in which an end of a cord is passed through a through hole in a cord holding section provided on the outer surface of a cylindrical body of the cord storage member until the center of the cord reaches the cord holding section, and the cord is then bent at the center and wound and stored in the cord storage member (see Patent Document 2). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Publication number 2-5715 [Patent Document 2] Publication No. 1-35629 Summary of the Invention [Problem to be solved by the invention]

[0005] The cord retention mechanisms disclosed in the above-mentioned Patent Documents 1 and 2 require a locking member to be fixed to the end of the nylon cord by crimping, etc. Also, there are products that use a fixed-length nylon cord specially made for use with cutting blades. In recent years, many nylon cord cutters for brush cutters using long nylon cords have been disclosed and sold, but they have problems such as the time-consuming task of attaching and replacing the nylon cord. [Means for solving the problem]

[0006] The present invention has been made to solve the above problems, and is comprised of a main body and a cover which are detachably attached to the drive shaft of a brush cutter. The main body has a mounting hole at its axis for mounting the drive shaft of the brush cutter, and a cylindrical wall is formed around the outer periphery of the mounting hole for removably fitting the cylindrical trunk of the cover. Locking pieces for locking the cover are formed on the inner periphery of the cylindrical wall, and a fixing mechanism for removably fixing the cover is formed from one of the locking pieces of the cover toward the outer periphery of the main body. Additionally, the outer periphery of the main body is provided with multiple pins (three in this embodiment) for retaining nylon cords.

[0007] The cover portion is provided with a cylindrical barrel having a bottom and an internal space, a pair of locking barrels are formed on the base end circumferential portion of the cylindrical barrel to be detachably fitted to the main body portion, and a large diameter flange, a small diameter flange, and a tubular barrel portion are provided on the outer periphery of the cylindrical barrel, around which a nylon cord is wound.

[0008] A cord insertion hole is carved into the cylindrical body between the large diameter flange and the small diameter flange, through which a nylon cord is inserted from the inner circumferential surface of the cylindrical body. A pair of pull-out grooves are formed on the outer circumferential edge of the large diameter flange to hold both ends of the wound nylon cord.

[0009] When the cylindrical barrel of the cover is brought close to the cylindrical wall of the main body, the magnets provided in the main body and cover attract them to each other, allowing the main body and cover to be easily inserted and fastened together. Effect of the Invention

[0010] The nylon cord cutter for brush cutters according to the present invention has two opposing cord insertion holes penetrating from the outer periphery to the outer periphery of the large diameter flange formed on the cover. Thus, when winding a nylon cord around the outer periphery of the cylindrical body, one end of the nylon cord is inserted from the inside to the outside of one of the insertion holes, the other end of the nylon cord is taken out from the inside to the outside of the other insertion hole, the ends of the two nylon cords are pulled out, and then the two nylon cords are wound together around the cylindrical body, and with any desired pulled-out length remaining, the nylon cord is wound around the nylon cord take-up part and then engaged in a pair of pull-out grooves formed on the circumferential edge of the large diameter flange. Thus, the winding operation can be easily performed.

[0011] In addition, a locking mechanism for attaching and detaching the main body and cover is formed on the surface of the main body. The mechanism is designed so that the main body is locked when turned counterclockwise and unlocked when turned clockwise, making attachment and detachment extremely easy.

[0012] The outer periphery of the main body is unevenly shaped, making it easy to grip and less likely to slip, so the main body and cover can be quickly attached and detached. Also, when the main body and cover are brought close to each other, the magnets embedded in the main body and cover attract each other, making it easy to insert, and allowing for quick fastening work. [Brief description of the drawings]

[0013] [Figure 1] 1 is a cross-sectional view of an assembled nylon cord cutter for a brush cutter according to the present invention. FIG. [Diagram 2] FIG. 2 is a plan view of the main body of the present invention; [Diagram 3] FIG. [Figure 4] FIG. 2 is a plan view of the cover of the present invention; [Diagram 5] FIG. 2 is a bottom view of the cover of the present invention. [Figure 6] FIG. 4 is an explanatory diagram of the fixing mechanism of the main body of the present invention, in which the fixing mechanism is in an open state. [Figure 7] FIG. 4 is an explanatory diagram of the fixing mechanism of the main body of the present invention, showing the fixing mechanism in a closed state. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] An embodiment of the present invention will be described with reference to the drawings. Fig. 1 is an assembled cross-sectional view of a nylon cord cutter 1 for a brush cutter, Fig. 2 is a plan view of a main body 2, and Fig. 3 is a rear view of the main body 2. In Figures 1 to 3, 1 is a nylon cord cutter of a brush cutter, 2 is a main body, 21 is a mounting hole for a drive shaft, 22 is a reinforcing ring, 23 is a nylon cord locking pin, 24a is an outer cylindrical body, and 24b is an inner cylindrical body. Also, 3 is a cover portion, 31 is a cylindrical body with a bottom, 32 is a large diameter flange, 33 is a small diameter flange, 34 is a cord winding portion, 35 is an insertion hole, 36 is a drawing groove, 37 is a locking claw, 4 is a lock mechanism, and 5 is a nylon cord. The main body portion 2 and the cover portion 3 are molded from synthetic resin.

[0015] 1 to 3, the outer periphery of the main body 2 is formed with projections and recesses 29 so that it can be easily gripped by hand. The main body 2 has a mounting hole 21 at its axial center for mounting a drive shaft (not shown) of a brush cutter, and the drive shaft (not shown) of the brush cutter is mounted in the mounting hole 21. A reinforcing ring 22 made of metal (e.g., stainless steel) is embedded in the mounting hole 21 to make the mounting hole 21 resistant to vibration and load.

[0016] An outer circumferential cylindrical barrel 24a is formed on the outer periphery of the main body 2, into which the outer periphery of the small diameter flange 33 of the cover 3 is detachably fitted. An inner circumferential cylindrical barrel 24b is erected in the middle between the outer circumferential cylindrical barrel 24a and the mounting hole 21 of the drive shaft, and is detachably attached to the outer periphery of the small diameter flange 33 formed on the cover 3. Three detachable locking claws 37 shown in Fig. 4 are provided on the circumference of the bottomed cylindrical body 31 of the cover part 3, which meshes with the L-shaped locking pieces 42 of the main body part 2. The locking claws 37 allow the main body part 2 and the cover part 3 to be attached and detached from each other by rotating the main body part 2 and the cover part 3 in opposite directions.

[0017] The lock mechanism 4 of the present invention will be described with reference to Figs. 2 to 4. An arc-shaped locking claw 42 is formed in the gap of an arc-shaped slit 41 carved on the circumference of the main body 2, and extends from the main body 2. The tip of the arc-shaped locking claw 42 has an elasticity that allows it to be pressed down. The tip of the arc-shaped locking claw 42 has an L-shaped cross section. The arc-shaped locking claw 42 acts as a key to lock and unlock the main body 2 and the cover 3 (fixing or releasing their mutual rotation). Furthermore, as the arcuate locking claws 42 rotate, the cylindrical body 26 also rotates. Three locking claws 25 are formed on the outer periphery of the cylindrical body 26 along the circumference.

[0018] On the other hand, three arc-shaped locking claws 37 that can be engaged with and disengaged from the locking claws 25 are formed on the outer periphery of the bottomed cylindrical body 31 of the cover part 3. The entrance of the locking claws 37 is open and the inner part is closed. Furthermore, a barb 45 is formed at the entrance to prevent the locking claws 25 from coming off.

[0019] On the inner circumferential surface of the area where the arc-shaped locking claws 42 of the main body are formed, three arc-shaped slits 43 are circumferentially formed. The arc-shaped slits 43 function as viewing windows for visually checking the engagement state of the locking claws 25 of the main body and the locking claws 37 of the cover when the arc-shaped locking claws 42 are locked.

[0020] The nylon cord cutter 1 according to the present application is configured such that, after the main body 2 and the cover 3 are brought into contact with each other, the main body 2 is simply rotated in the locking direction, and the locking claws 25 formed at equal intervals on the circumference of the main body engage with three locking claws 37 formed at equal intervals on the circumference of the cover 3, thereby locking the main body 2 in place. Furthermore, when the arc-shaped engaging claw 42 of the locking mechanism 4 formed on the main body 2 is rotated in the unlocking direction while being pressed down with a finger or the like, the connection between the main body 2 and the cover 3 is released. In this way, the locking operation can be performed quickly and easily, resulting in extremely good work efficiency.

[0021] 3, three nylon cord locking pins 23 are provided at equal intervals on a circumference near the outer periphery of the inner surface of the main body 2. The nylon cord locking pins 23 prevent the nylon cord 5 from jumping out of the cord winding portion 34 due to the elastic force of the nylon cord 5 when the nylon cord 5 is wound around the cord winding portion 34 between the large diameter flange 32 and the small diameter flange 33 of the cover 3.

[0022] The nylon cord 5 extends from the outer peripheral edge of the main body 2, and even if a large load is applied due to centrifugal force when cutting weeds, etc., the load is relieved by the pin 23, so that the nylon cord 5 does not get tangled in the nylon cord 5 wound around the winding part.

[0023] In FIG. 4, the cover portion 3 is provided with a bottomed cylindrical body 31 having an internal space, and three locking claws 37 are formed on the base end circumference of the bottomed cylindrical body 31 to be detachably fitted to the main body portion 2.

[0024] Large diameter flange 32 and small diameter flange 33 for winding and holding nylon cord 5 are erected in the circumferential direction from the side surface of bottomed cylindrical body 31, and a pair of cord insertion holes 35 for inserting nylon cord 5 are provided at three locations on the circumference in the space between large diameter flange 32 and small diameter flange 33. In addition, a pair of pull-out grooves 36 for pulling out nylon cord 5 from cover portion 3 are formed on the outer circumferential edge of large diameter flange 32.

[0025] The pull-out groove 36 for pulling out the nylon cord 5 has a generally T-shaped notch 39 carved from the circumferential edge of the cover portion 3 toward the axial center with a width that allows the nylon cord 5 to be inserted. The plate thickness side of the notch 39 has a slope formed in the opposite direction to the rotation direction of the nylon cord cutter. This allows the nylon cord 5 to be smoothly pulled out of the pull-out groove 36 of the nylon cord cutter and stretched radially by centrifugal force for brush cutting work. The shape of the pull-out groove 36 is not limited to an L-shape, but may be a circle, an ellipse, a polygon, or the like.

[0026] In this embodiment, one nylon cord 5 is inserted, but since the insertion holes 35 for the nylon cord 5 are formed at three locations on the circumference, the user can select the desired insertion hole 35 and insert the nylon cord 5 into it.

[0027] Fig. 5 is a bottom view of the cover part 3. In Fig. 5, six arc-shaped grip parts 51 are formed in the center, and the grip parts 51 can be held, rotated, or separated from the main body part while being held with the fingertips. A pair of cutouts 36 provided opposite to each other on the circumferential edge of the large diameter flange 32 are pull-out grooves 36 for pulling out and locking the nylon cord 5 from the nylon cord winding part 34. The pull-out grooves 36 are cut out in an L shape to prevent damage to the nylon cord 5, and the thick plate part is formed as a slope toward the rear in the direction of rotation.

[0028] 6 and 7 are explanatory diagrams of the operation of the locking mechanism 4 of the present invention, with the main body 2 shown in dashed lines and the cover 3 shown in solid lines, overlapping each other. Fig. 6 shows the engaged state before the locking mechanism is activated or after it is released (the locking claw 42 is located at the upper right), and Fig. 7 shows the engaged state when the locking mechanism is activated (the locking claw 42 is located at the upper left).

[0029] This is done by operating the arc-shaped locking claw 42 of the locking mechanism 4 to rotate the main body 2 and the cover 3 relative to each other. In Fig. 6 (released state), when the main body 2 and the cover 3 are held with both hands and rotated in opposite directions (for example, holding the cover 3 and rotating the main body 2 counterclockwise), the locking claws 25 of the main body 2 are inserted into the locking claws 37 of the cover 3, resulting in the state shown in Fig. 7, in which the main body 2 and the cover 3 are fixed together. In this state, mowing work can be performed.

[0030] To release the locked state, grasp main body portion 2 and cover portion 3 with both hands, press with your fingertips arc-shaped locking claw 42 formed on the inside of arc-shaped slit 41 carved into the surface of main body portion 2, and rotate them in opposite directions (for example, turn main body portion 2 clockwise while still grasping cover portion 3). This will disengage locking claw 25 of main body portion 2 from locking claw 37 of cover 3 (as shown in FIG. 6), allowing main body portion 2 and cover portion 3 to be separated. In this state, if main body portion 2 is removed, nylon cord 5 can be wound around cover portion 3.

[0031] Furthermore, the cover portion 3 can be attached and detached while the main body portion 2 remains attached to the drive shaft of the brush cutter. This eliminates the need to detach the main body portion 2 from the drive shaft of the brush cutter when replacing the nylon cord 5, thereby further improving the efficiency of the nylon cord 5 replacement work. [Industrial Applicability]

[0032] The cord retaining device of the present invention not only makes it easy to replace the nylon cord 5, but also makes it extremely easy to attach and detach the main body 2 and cover 3 in a short time, making it suitable for use in a wide range of brush cutters that use nylon cord 5. [Explanation of symbols]

[0033] 1 nylon cord cutter 2 Main unit 21 Mounting holes 22 Reinforcement ring 23 pin 24a Outer cylindrical shell 24b Inner cylindrical shell 25 Locking claw 26 Cylindrical body 28 Pressing part 29 Uneven shape 3 Cover 31 Cylindrical shell with bottom 32 Large diameter flange 33 Small diameter flange 34 Cord winding section 35 Insertion hole 36 Pull-out groove 37 Locking claw 4 Locking mechanism 41 Circular slit 42 Arc-shaped locking claw 43 Arc-shaped hole 45 Return 5 Nylon Cord

Claims

1. The main body has a drive shaft mounting hole at its axis, a cylindrical barrel formed around the outer periphery of the mounting hole for removably fitting the cylindrical barrel of the cover, a plurality of cover retaining tabs formed on the inner periphery of the cylindrical barrel, and a plurality of nylon cord retaining pins provided on the inner periphery of the main body, a nylon cord cutter for a brush cutter, characterized in that the cover portion comprises a bottomed cylindrical barrel having an internal space, a plurality of locking claws formed on the circumferential portion of the base end of the cylindrical barrel for removably fitting with the main body portion, a large diameter flange and a small diameter flange provided on the outer periphery of the cylindrical barrel for winding a nylon cord, and a pair of nylon cord pull-out grooves formed on the circumferential edge of the large diameter flange.

2. 2. The nylon cord cutter for a brush cutter according to claim 1, wherein a locking mechanism provided on the circumferential surface of said main body enables said main body and said cover to be easily and quickly attached and detached from each other.

3. 3. The nylon cord cutter for a brush cutter according to claim 1, wherein a plurality of magnets are attached to the inner peripheral portion of the main body, and magnets are embedded in the cover portion at positions opposite to the magnets of the main body.

Images