JP2022115122A - Bush cutting head for cord-type bush cutter and cord-type bush cutter using the brush cutting head - Google Patents

Abstract

To provide a bush cutting head for a cord-type bush cutter which can suppress the wear of a cord cutter and can alleviate a burden on a power source, and a cord-type bush cutter using the bush cutting head.SOLUTION: There are provided: a bush cutting head 1 for a cord-type bush cutter which is composed of a head main body 2 rotatably attached to an attachment shaft 52 arranged at a tip part of an operation rod 50, and a cutter cover 3 arranged at an upper part of the head main body 2 integrally therewith; and the cord-type bush cutter using the bush cutting head 1. A diameter of the cutter cover 3 is twice or more of a diameter of the head main body 2 and is four times thereof or less. Also, when making an outer edge part of a lower end of the head main body 2 and an outer edge part of the cutter cover 3 abut on a horizontal face, an angle formed by a lower face and the horizontal face of the cutter cover 3 is equal to or smaller than 30°. Furthermore, a maximum value of a jump-up angle being an angle formed of a virtual linear line for connecting a cord outlet 38 and a tip of a cord cutter C and a rotation face of the cord cutter C is equal to or smaller than 15°.SELECTED DRAWING: Figure 2

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cord-type brush cutter head provided at the tip of an operating rod of the cord-type brush cutter, and a cord-type brush cutter using this brush cutter head.

A cord-type brush cutter has a cord cutter, such as a nylon cord, protruding from the brush-cutting head attached to the tip of the operating rod. It's becoming Since the cord cutter rotates around the axis of the cutting head, the portion farther from the cutting head (hereinafter referred to as the "tip portion of the cord cutter" in this specification) is closer to the cutting head (hereinafter referred to as the "end portion of the cord cutter"). , in this specification, referred to as "the proximal end portion of the cord cutter")), and has a higher cutting ability. Therefore, by cutting grass with the tip of the cord cutter, the load on the power source can be reduced and the cord type brush cutter can be operated stably. In addition, if the angle formed by the rotation plane of the cord cutter and the ground surface becomes large during operation of the cord-type brush cutter, the tip of the cord cutter is likely to come into contact with the ground surface. It will be a burden. Therefore, it is desirable that the plane of rotation of the cord cutter and the ground surface are parallel or nearly parallel.

2. Description of the Related Art In recent years, rechargeable cord-type brush cutters are being used more and more due to environmental concerns, convenience, and the like. With this cord-type brush cutter, mowing grass with parts other than the tip of the cord cutter, or setting the rotating surface of the cord cutter at an angle to the ground surface, increases power consumption and shortens battery life. put away. Therefore, in order to extend the life of the battery in rechargeable cord-type brush cutters, it is necessary to mow the grass with the tip of the cord cutter and to make the rotating surface of the cord cutter parallel or nearly parallel to the ground surface. is particularly required.

2. Description of the Related Art Conventionally, a cord-type brush cutter head disclosed in Patent Document 1 and a cord-type brush cutter using this brush cutter head are known. In this cord-type bush cutter, a cord cutter (nylon cord cutting blade 4a) protrudes from a bush-cutting head (holding member 100) attached to the tip of an operating rod (operating tube 12), and a power source (small engine 11) is used. By rotating the cutting head (holding member 100) at high speed, the cord cutter (nylon cord cutting blade 4a) rotates at high speed around the axis of the cutting head (holding member 100). A disk-shaped cord cutter cover (guide member 200) is attached to the lower end of the cutting head (holding member 100). In this cord-type brush cutter, the cord cutter (nylon cord cutting blade 4a) inside the outer circumference of the cord cutter cover (guide member 200) does not hit the grass, and the cord cutter (nylon cord cutting blade 4a) outside the outer circumference does not hit the grass. can cut grass. Therefore, according to this cord-type brush cutter, grass can be cut with the tip portion of the cord cutter (nylon cord cutting blade 4a), so it is considered that the power source is less likely to be burdened.

Japanese Patent No. 6106091 (P4, Figures 1 to 3)

However, in the cord-type brush cutter of Patent Document 1, if the cord cutter (nylon cord cutting blade 4a) hits an uneven ground surface, stones, etc. during mowing work, the tip of the cord cutter (nylon cord cutting blade 4a) As a result, the operation of the cord type brush cutter becomes unstable and the work efficiency tends to decrease. Also, although the diameter of the cord cutter cover (guide member 200) is larger than the diameter of the cutting head (holding member 100), the specific size is not shown. As a result, the angle between the cord cutter (nylon cord cutting blade 4a) and the ground surface increases during mowing, and the tip of the cord cutter (nylon cord cutting blade 4a) may hit the ground surface.

SUMMARY OF THE INVENTION The present invention has been made in view of such conventional problems. To provide a cord type brush cutter using

In order to solve the above problems, the brush cutting head for a cord type brush cutter according to claim 1 is characterized by a substantially cylindrical head body rotatably attached to an attachment shaft provided at the tip of an operation rod. and a substantially doughnut-shaped cutter cover integrally provided on the upper part of the head main body. A cord cutter having both ends protruding from one cord outlet, the diameter of the cutter cover being two to four times the diameter of the head body, the outer edge of the lower end of the head body and the cutter When the outer edge of the cover is brought into contact with a horizontal surface, the angle formed by the lower surface of the cutter cover and the horizontal surface is 30 degrees or less, and the imaginary straight line connecting the cord outlet and the tip of the cord cutter and the cord The maximum value of the bounce angle, which is the angle between the cutter and the rotating surface, should be 15 degrees or less.

A feature of the brush cutting head for a cord type brush cutter according to claim 2 is that a thick protective projection is formed on the outer edge of the cutter cover.

The brush cutting head for a cord type brush cutter according to claim 3 is characterized in that the head main body includes a cord holder around which the cord cutter is wound, and a cord holder disposed above the cord holder to accommodate the cord cutter at both ends. and a lid arranged on the upper part of the case, the lid is integrally provided with the cutter cover, and one of the lid and the case has a locking claw at the tip. A stopper is rotatably pivoted, and the other of the lid or the case has a plurality of locking surfaces that engage with the locking claws to rotate the case integrally with the cord holder and the lid. A return portion provided at the rear end of the stopper is guided to the other of the lid or the case to move the locking pawl along the outer peripheral surface. It is that the guiding portion for allowing the movement is provided inside the outer peripheral surface.

The cord-type brush cutter according to claim 4 is characterized by the operation rod, the gear box attached to the tip of the operation rod, the attachment shaft projecting from the gear box, and the attachment shaft being rotatable. A cord type brush cutter head according to any one of claims 1 to 3 is attached, and a power source for rotating the brush cutter head at high speed.

In the brush cutting head for a cord type brush cutter according to claim 1, since the cutter cover is provided above the cord exit from which the cord cutter protrudes, the cord cutter is prevented from hitting uneven ground surfaces, stones, etc. However, the base end of the cord cutter is not flipped up by the cutter cover. Further, since the surface of the cutter cover and the rotation plane of the cord cutter are substantially parallel, the angle between the rotation plane of the cord cutter and the ground surface can be easily grasped by visually checking the surface of the cutter cover. Therefore, by making the surface of the cutter cover substantially parallel to the ground surface, the rotating surface of the cord cutter and the ground surface can be easily maintained parallel or at an angle close to parallel. Furthermore, since the tip of the cord cutter is located outside the outer edge of the cutter cover, the mowing position can be reliably grasped by using the outer edge of the cutter cover as a guide.

In addition, since the diameter of the cutter cover is two to four times the diameter of the head body, it is easy to cut grass with the tip of the cord cutter while maintaining the operability of the cord type brush cutter. That is, if the diameter of the cutter cover is less than twice the diameter of the head body, the base end of the cord cutter, which has poor cutting ability, will protrude from the cutter cover, increasing the load on the power source and stabilizing cord-type cutting. It becomes difficult to operate the machine. In addition, if the diameter of the cutter cover is more than four times the diameter of the head body, the length of the cord cutter protruding from the cord outlet of the head body becomes longer, increasing the load on the power source and increasing the weight and surface area of the cutter cover. increases and the operability of the cord-type brush cutter deteriorates.

Further, when the outer edge of the lower end of the head body and the outer edge of the cutter cover are brought into contact with a horizontal plane, the angle formed by the lower surface of the cutter cover and the horizontal plane is 30 degrees or less. Therefore, the tip part of the cord cutter can be lowered to near the ground surface while the surface of the cutter cover and the ground surface are maintained in a substantially horizontal state, and the tip part of the cord cutter can be cut to the root of the grass without touching the ground surface. be able to. On the other hand, if the angle formed by the lower surface of the cutter cover and the horizontal plane is greater than 30 degrees, it is not possible to mow the grass to the root unless the surface of the cutter cover is greatly tilted with respect to the ground surface. Easy to hit the ground surface.

In addition, since the maximum value of the bounce angle, which is the angle between the imaginary straight line connecting the cord exit and the tip of the cord cutter and the rotating surface of the cord cutter, is 15 degrees or less, the vertical movement of the cord cutter is not so large. It is possible to stably operate the cord type brush cutter. Therefore, according to this brush cutting head for a cord type brush cutter, it is possible to suppress wear of the cord cutter and reduce the load on the power source.

In the brush cutting head for a cord type brush cutter according to claim 2, a thick protection projection is formed on the outer edge of the cutter cover. Therefore, damage to the cutter cover can be suppressed even when an obstacle such as a stone hits the outer edge of the cutter cover, or when the cord cutter bounces up and hits the outer edge of the cutter cover.

In the brush cutting head for a cord type brush cutter according to claim 3, not only the cutter cover is provided integrally with the lid, but also either the stopper or the outer peripheral surface is provided. Therefore, the lid itself serves multiple roles, and the number of parts can be reduced. Further, in this cord-type brush cutter head, when the rotation of the cord holder is smaller than the predetermined rotation, the locking claw and the locking surface are engaged to rotate the case integrally with the cord holder and the lid. When the rotation of the cord holder exceeds a predetermined number of rotations, the centrifugal force acting on the stopper increases, disengaging the engaging pawl from the engaging surface and allowing the case, cord holder, and lid to rotate relative to each other. . At this time, the return portion and the guide portion move the locking pawl along the outer peripheral surface to the position of engagement with the next locking surface, and the cord of a certain length is let out. As long as the cord holder rotates a predetermined number of times or more, this operation occurs continuously, and the movement of the locking pawl to the engaging position with the adjacent locking surface is not skipped. and does not rotate rapidly against the lid. Therefore, even if the locking claw and the locking surface are engaged with each other, a strong impact force is not applied to the stopper, and damage to the stopper and the locking surface can be suppressed.

Since the cord-type brush cutter according to claim 4 uses the above-described cord-type brush cutter head, it is possible to suppress wear of the cord cutter and reduce the load on the power source. In particular, in a cord-type brush cutter that uses a battery as a power source, the duration of the battery can be extended, and this effect is significant.

1 is a perspective view of a cord-type brush cutter according to an embodiment; FIG. FIG. 2 is a drawing showing how the brush cutting head for the cord type brush cutter of the embodiment is attached to the cord type brush cutter. 1 is an exploded perspective view of a brush cutting head for a cord type brush cutter according to an embodiment; FIG. FIG. 2 is an enlarged cross-sectional view of the outer edge portion of the cutter cover of the cord-type brush cutter head of the embodiment. Fig. 4 is a diagram showing the relationship between the diameter of the cutter cover and the diameter of the head body, relating to the brush cutting head for the cord type brush cutter of the embodiment; FIG. 2 is a view of the cord-type brush cutter head of the embodiment, showing a state where the head body and the cutter cover are brought into contact with a horizontal surface; Fig. 2 is a view showing the upturn angle of the cord cutter in the brush cutting head for the cord type brush cutter according to the embodiment;

DETAILED DESCRIPTION OF THE INVENTION Embodiments of a cord type brush cutter head according to the present invention and a cord type brush cutter using the cord type brush cutter head will be described below with reference to the drawings. FIG. 1 is a perspective view of a cord-type brush cutter. As shown in FIG. 1, this cord-type brush cutter includes an operating rod 50, a gear box 51 attached to the tip of the operating rod 50, and a cord-type brush cutter rotatably attached to the gear box 51. It has a cutting head 1 (hereinafter referred to as "brush cutting head 1") and a battery 55 as a power source for rotating the cutting head 1 at high speed.

FIG. 2 is a diagram showing how the brush cutting head 1 is attached to the operation rod 50 of the cord type brush cutter. As shown in FIG. 2, the brush cutting head 1 is attached by bolts 53 to a mounting shaft 52 protruding from a gear box 51 at the tip of an operating rod 50 of the cord type brush cutter. The weeding head 1 is composed of a substantially cylindrical head body 2 and a substantially doughnut-shaped cutter cover 3 integrally provided on the top of the head body 2 . The head body 2 has a cord cutter C with both ends protruding from two cord outlets 38 provided below the cutter cover 3 . In this cutting head 1, since the cutter cover 3 is provided above the cord outlet 38 from which the cord cutter C protrudes, even if the cord cutter C hits unevenness of the ground surface, stones, etc., the cutter will not be cut off. The cover 3 prevents the base end of the cord cutter C from being flipped up. Further, since the surface of the cutter cover 3 and the rotation plane of the cord cutter C are substantially parallel, the angle between the rotation plane of the cord cutter C and the ground surface can be easily grasped by visually checking the surface of the cutter cover 3. be able to. Furthermore, since the tip of the cord cutter C is outside the outer edge of the cutter cover 3, the mowing position can be reliably grasped by using the outer edge of the cutter cover 3 as a guide.

FIG. 3 is an exploded perspective view of the brush cutting head 1. FIG. As shown in FIG. 3, this head body 1 has a lid 10, a stopper 20, a spring 25, a case 30, and a cord holder 40. As shown in FIG. The cutting head 1 can cut grass by rotating both ends of the cord C around the axis L of the attachment shaft 52 at high speed. The lid 10 has a hollow disk-shaped lid body 11 and a cylindrical portion 12 projecting from the center of the lid body 11 . A cutter cover 3 is provided integrally with the lid body 11 . A female thread 12a is formed on the inner periphery of the cylindrical portion 12, and the female thread 12a is screwed with a male thread 41b formed on the outer peripheral portion of the cylindrical portion 41 of the cord holder 40, which will be described later. By screwing the female screw 12a and the male screw 41b together to fix the lid 10 and the cord holder 40 together, the lid 10 and the cord holder 40 can be rotated integrally. Also, two cylindrical rotating struts 13, two cylindrical pressing struts 14, and two mounting portions 15 are provided at symmetrical positions on concentric circles.

The cutter cover 3 is composed of a concave portion 4 which has a through hole in the center and is recessed upward, and a flange portion 5 provided continuously from the concave portion 4 to the outside. The concave portion 4 and the lid body 11 are integrally formed. In addition, a thick protective projection 5a is formed on the rear surface of the outer edge portion of the collar portion 5, and a groove 5b is formed on the front surface. FIG. 4 is an enlarged cross-sectional view of the outer edge of the cutter cover 3. As shown in FIG. As shown in FIG. 4, the protective protrusion 5a has a substantially trapezoidal cross section, but it may also have a semicircular shape, an inverted triangular shape, or the like. The protection projection 5a can prevent the cutter cover 3 from being damaged even when an obstacle such as a stone hits the outer edge of the flange 5 or when a cord cutter jumps up and hits it. Further, the grooves are formed concentrically around the axis L, and although three grooves are formed in this embodiment, the number of grooves may be more than three, or may be one. The groove 5b is provided to balance the weight of the outer edge of the cutter cover 3 with the protective protrusions 5a so that the outer edge of the cutter cover 3 does not become too heavy, and to reduce the weight of the cutter cover 3 as a whole. The configuration, operation, and effects of the brush cutting head 1 other than the lid 10 are substantially the same as those of Japanese Patent Application Laid-Open No. 2016-59310 previously filed by the inventor of the present application, and will be briefly described below.

As shown in FIG. 3, the stopper 20 has a plate-like shape that is slightly bent into a hook shape. is open. The rotation support 13 of the lid 10 is inserted into the rotation hole 21, and the stopper 20 is rotatable around the rotation support 13. As shown in FIG. A locking claw 22 is formed on the distal end portion 20a. Furthermore, the weight from the rotation hole 21 to the rear end portion 20b is heavier than the weight from the rotation hole 21 to the tip portion 20a. A step portion 24 is formed in the tip portion 20a. A cylindrical projection 23 as a return portion protrudes toward the case 30 from the rear end portion 20b.

The spring 25 is a torsion spring and consists of a coil portion 25a, a first arm 25b and a second arm 25c. The pressing strut 13 of the lid 10 is inserted into the coil portion 25a, and the first arm 25b is hung on the mounting portion 15 of the lid 10. As shown in FIG. Then, the second arm 25c is hung on the stepped portion 24 of the stopper 20 . As a result, the tip 20 a of the stopper 20 is pressed radially outward of the lid 10 by the spring 25 .

The case 30 has a cylindrical shape with concave portions 31 and 32 on both sides and an insertion hole 30a in the center. A stopper 20 is accommodated in the recess 31, and an outer peripheral surface 33 for guiding the locking claws 22 of the stopper 20 is formed in a circular shape on the outer periphery. A locking surface 34 for locking is formed. A projection 35 is provided inside the outer peripheral surface 33 as a guiding portion for guiding the protrusion 23 provided on the rear end portion 20 b of the stopper 20 to move the locking claw 22 along the outer peripheral surface 33 . It is The protrusion 23 is slid on the side surface of the ridge 35 on the axial center L side to force the locking claw 22 to move along the outer peripheral surface 33 . Two sets of cord outlets 38 are provided at symmetrical positions on the outer periphery on the side of the recess 32 .

The cord holder 40 has a cylindrical portion 41 , a bottom plate 42 and a flange 43 . The cylindrical portion 41 has a cylindrical shape and is erected in the center of a hollow disk-shaped bottom plate 42 . A disc-shaped flange 43 is provided in the central portion of the cylindrical portion 41 , and a cord winding portion 44 is formed between the bottom plate 42 and the flange 43 . The cord C is wound around the cord winding portion 44 and stored. Two through-holes (not shown) are formed at symmetrical positions of the cylindrical portion 41 located in the winding portion 44 . A male screw 41b is formed on the outer peripheral portion of the cylindrical portion 41 on the distal end side of the cord winding portion 44 . Further, a central hole 41a is formed in the inner peripheral surface of the cylindrical portion 41, and the cord C can be inserted into the cord winding portion 44 through the through hole from the central hole 41a when winding the cord C. It's becoming

In this bush cutting head 1, when the rotation of the cord holder 40 is less than a predetermined rotation, the engaging claw 22 and the engaging surface 34 engage to rotate the case 30 integrally with the cord holder 40 and the lid 10. . When the rotation of the cord holder 40 exceeds a predetermined number of rotations, the centrifugal force acting on the stopper 20 increases, disengaging the locking pawl 22 from the locking surface 34, and the case 30, cord holder 40 and The lid 10 rotates relatively. At this time, the projection 23 and the projection 35 move the locking claw 22 along the outer peripheral surface 33 to the engagement position with the next locking surface 34, and the cord C of a certain length is drawn out. While the rotation of the cord holder 40 is more than the predetermined rotation, this operation occurs continuously, and the movement of the locking claw 22 to the engaging position with the adjacent locking surface 34 is not skipped. 30 does not rotate rapidly with respect to cord holder 40 and lid 10 . Therefore, even if the locking claw 22 and the locking surface 34 are engaged with each other, a strong impact force is not applied to the stopper 20, and breakage of the stopper 20 and the locking surface 34 can be suppressed. Further, since the cord C continues to be let out until the rotation of the cord holder 40 becomes smaller than the predetermined rotation and the engaging claw 22 and the engaging surface 34 are engaged with each other, the cord C protruding from the case 40 has a predetermined length. is ensured.

Next, the relationship between the cutter cover 3 and the head main body 2 of the weeding head 1 having the above configuration, functions and effects will be described with reference to FIGS. 5 to 7. FIG. FIG. 5 is a diagram showing the relationship between the diameter φ2 of the cutter cover 3 and the diameter φ1 of the head body 2. As shown in FIG. The diameter φ2 of the cutter cover 3 is two times or more and four times or less the diameter φ1 of the head body 2, so that the tip of the cord cutter C can easily cut grass while maintaining the operability of the cord type brush cutter. Here, if the diameter φ2 of the cutter cover 3 is smaller than twice the diameter φ1 of the head body 1, the base end portion of the cord cutter C, which has inferior cutting ability, will protrude from the cutter cover 3, increasing the load on the battery 55. In addition, it becomes difficult to stably operate the cord-type brush cutter. Further, if the diameter φ2 of the cutter cover 3 is larger than 4 times the diameter φ1 of the head body 1, the length of the cord cutter C protruding from the cord outlet 38 of the head body 1 becomes longer and the load on the battery 55 increases. The weight and surface area of the cutter cover 3 are increased, and the operability of the cord type brush cutter is deteriorated.

FIG. 6 is a diagram showing a state in which the head body 2 and the cutter cover 3 are brought into contact with the horizontal surface HP. However, the cord cutter C is omitted. As shown in FIG. 6, when the outer edge of the lower end of the head body 2 and the outer edge of the cutter cover 3 are brought into contact with the horizontal plane HP, the angle θ1 formed by the lower surface of the cutter cover 3 and the horizontal plane HP is 30 degrees or less. is. Therefore, the tip portion of the cord cutter C can be lowered to near the ground surface while the surface of the cutter cover 3 and the ground surface are kept substantially horizontal, and the tip portion of the cord cutter C can be lowered to the ground surface without touching the ground surface. You can mow it down. On the other hand, if the angle θ1 between the lower surface of the cutter cover 3 and the horizontal plane HP is greater than 30 degrees, the grass cannot be cut to the root unless the surface of the cutter cover 3 is greatly inclined with respect to the ground surface. The tip of C is likely to hit the ground surface.

FIG. 7 is a diagram showing the bounce angle θ2 of the cord cutter C. As shown in FIG. Here, the bounce angle .theta.2 is the angle formed by the rotation plane SR of the cord cutter C and the imaginary straight line VL connecting the cord outlet 38 of the head body 2 and the tip of the cord cutter C. As shown in FIG. The maximum value of this bounce angle θ2 is 15 degrees or less. Therefore, even if the cord cutter C is hit by an obstacle such as a stone, the vertical movement of the cord cutter C does not increase so much.

In the cord-type brush cutter head of the embodiment, since the cutter cover 3 is provided above the cord outlet 38 from which the cord cutter C protrudes, the cord cutter C does not hit the unevenness of the ground surface, stones, etc. Even in this case, the cutter cover 3 prevents the base end of the cord cutter C from being flipped up. Further, since the surface of the cutter cover 3 and the rotation plane of the cord cutter C are substantially parallel, the angle between the rotation plane of the cord cutter C and the ground surface can be easily grasped by visually checking the surface of the cutter cover 3. be able to. Therefore, by making the surface of the cutter cover 3 substantially parallel to the ground surface, the rotating surface of the cord cutter C and the ground surface can be easily maintained in parallel or at an angle close to parallel. Furthermore, since the tip of the cord cutter C is outside the outer edge of the cutter cover 3, the mowing position can be reliably grasped by using the outer edge of the cutter cover 3 as a guide.

In addition, since the diameter φ2 of the cutter cover 3 is two times or more and four times or less the diameter φ1 of the head body 2, it is easy to cut grass with the tip of the cord cutter C while maintaining the operability of the cord type brush cutter. . Further, when the outer edge of the lower end of the head body 1 and the outer edge of the cutter cover 3 are brought into contact with the horizontal plane HP, the angle formed by the lower surface of the cutter cover 3 and the horizontal plane HP is 30 degrees or less. Therefore, the tip portion of the cord cutter C can be lowered to near the ground surface while the surface of the cutter cover 3 and the ground surface are kept substantially horizontal, and the tip portion of the cord cutter C can be lowered to the ground surface without touching the ground surface. You can mow it down. In addition, since the maximum value of the bounce angle θ2, which is the angle between the imaginary straight line VL connecting the cord outlet 38 and the tip of the cord cutter C and the rotation surface SR of the cord cutter C, is 15 degrees or less. The vertical movement is not so large, and stable operation of the cord-type brush cutter is possible. Therefore, according to this brush cutting head for a cord type brush cutter, it is possible to suppress consumption of the cord cutter C and reduce the load on the battery 55 .

Further, in this cord-type brush cutter head, a thick protection projection 5 a is formed on the outer edge of the cutter cover 3 . Therefore, when an obstacle such as a stone hits the outer edge of the cutter cover 3, damage to the cutter cover 3 can be suppressed.

Further, in this cord-type brush cutter head, not only is the lid 10 integrally provided with the cutter cover 3, but also the stopper 20 is provided. Therefore, the lid 10 itself serves multiple roles, and the number of parts can be reduced.

In addition, since the cord-type brush cutter uses the brush-cutting head 1, it is possible to suppress consumption of the cord cutter C and reduce the load on the battery 55, thereby extending the life of the battery 55.例文帳に追加

The cord type brush cutter head 1 of the present invention and the cord type brush cutter using the cord type brush cutter head 1 have been described above, but the present invention is not limited to these. It goes without saying that the present invention can be modified as appropriate and applied as long as it does not contradict the technical idea of the present invention.

DESCRIPTION OF SYMBOLS 1... Weeding head, 2... Head main body, 3... Cutter cover, 5a... Protective protrusion, 10... Lid, 20... Stopper, 22... Locking claw, 23... Return part (protrusion), 30... Case, 33... Periphery Surface 34 Locking surface 35 Induction part (protrusion) 38 Cord outlet 40 Cord holder 50 Operating rod 51 Gear box 52 Mounting shaft 55 Power source (battery) C: code, HP: horizontal plane, VL: virtual straight line, SR: plane of rotation, θ2: bounce angle.

Claims (4)

A cord-type mower consisting of a substantially cylindrical head body rotatably attached to a mounting shaft provided at the tip of an operating rod, and a substantially doughnut-shaped cutter cover integrally provided on the top of the head body. A mowing head for a mower,
The head body has a cord cutter with both ends protruding from two cord outlets provided below the cutter cover,
The diameter of the cutter cover is two times or more and four times or less the diameter of the head body,
When the outer edge of the lower end of the head body and the outer edge of the cutter cover are brought into contact with a horizontal plane, the angle formed by the lower surface of the cutter cover and the horizontal plane is 30 degrees or less,
A mower for a cord type brush cutter, characterized in that the maximum value of a bounce angle formed by an imaginary straight line connecting the cord outlet and the tip of the cord cutter and the rotating surface of the cord cutter is 15 degrees or less. pay head. 2. A brush cutting head for a cord type brush cutter according to claim 1, wherein a thick protective projection is formed on the outer edge of said cutter cover. The head body includes: a cord holder around which the cord cutter is wound and rotated about the axis of the mounting shaft; a case disposed above the cord holder and accommodating the cord cutter and projecting both ends thereof; and the case. and a lid that rotates integrally with the cord holder disposed on the top of the
The lid is integrally provided with the cutter cover,
A stopper having an engaging claw at its tip is rotatably supported on one of the lid and the case,
The other of the lid and the case is formed with a circular outer peripheral surface having a plurality of locking surfaces that engage with the locking claws and rotate the case integrally with the cord holder and the lid,
The other of the lid and the case has a guiding portion inside the outer peripheral surface for guiding the return portion provided at the rear end of the stopper to move the locking pawl along the outer peripheral surface. 3. The brush cutting head for a cord type brush cutter according to claim 1 or 2, wherein the brush cutting head is provided with: 4. Any one of claims 1 to 3, wherein said operating rod, a gearbox attached to the tip of said operating rod, said attachment shaft protruding from said gearbox, and rotatably attached to said attachment shaft. A cord type brush cutter comprising: a cord type brush cutter head according to claim 1; and a power source for rotating the cord type brush cutter head at high speed.

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