JP2006314277A - Brush cutter - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a brush cutter capable of being driven by each of an engine and an electrically driven motor according to the use environment as a power source. <P>SOLUTION: A double-edged blade-type cutter 13 is joined to the tip of an operation arm 10 so as to be freely detachable. A follow-side joint 17 is installed in the rear side of the operation arm 10, and each of an engine output-side joint 30 of the engine 187, and a motor output-side joint 31 of the electrically driven motor 19 is selectively and detachably attached to the follow-side joint 17. The electrically driven motor 19 can be rotated in each normal or reverse direction by a selection switch 45, and the bush-cutting operation can be carried out at each of the normal and reverse rotations of the double-edged blade-type cutter 13. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a brush cutter capable of driving a cutter using either an engine or an electric motor as a power source.

  Brush cutters, also called mowers, are used to cut weeds that grow on the banks of Tabata and the banks of Kawahara, undergrowth and pasture of mountain forests. There are two types of brush cutters: an arm connection type in which a cutter is attached to the tip of the operating arm and a power source is attached to the rear end, and a direct-acting type in which a cutter is directly attached to the rotary shaft of the power source. As a source, there are a case where an engine is mounted and a case where an electric motor is mounted.

  A brush cutter using an electric motor as a power source is, for example, a linear motion type in which an electric motor is attached to the tip of an operation arm and a cutter is directly attached to the shaft of the electric motor, as described in Patent Document 1. Many. As described in Patent Document 2, for example, there are many arm connection types in which a cutter is attached to the front end of the operation arm and the engine is attached to the rear end.

For the arm connection type with the cutter attached to the tip of the operation arm and the engine attached to the rear end, the shoulder belt type with the engine mounted on the backrest and the loop belt attached to the operation arm on the shoulder There are a shoulder type that can be hung on a handle, a handle type that is operated by holding a handle provided on an operation arm, and the handle includes a loop handle and a two-hand handle. The cutter attached to these brush cutters has a disk-shaped metal blade provided with a plurality of cutting blades. Depending on the number of blades, four blades, eight blades, and 30 or more cutting blades are saw blades. There is what was provided in the shape. Conventionally, a single-edged metal blade in which a cutting edge is provided only on one side surface of the cutting blade is often used.
Japanese Utility Model Publication No.5-2620 JP 2004-8054 A

  When mowing with a single-edged cutter attached to such a brush cutter, the cutting surface of the cutting blade on the traveling direction side contacts the weeds by moving the rotating cutter almost parallel to the ground. Let this be reaped. In an arm-type brush cutter with a single-edged cutter attached, for example, the operator returns the arm to the position where it is swung to the right, and then swings the cutter from the right to the left by shaking it left. Mowing while moving. After swinging the arm once and mowing, the operator moves forward and similarly returns the arm to the right and then swings to the left to move the cutter from the right to the left. Do. The operator repeats the swinging and reciprocating movement of the arm until the mowing at the predetermined mowing site is completed, and when the cutter rotates counterclockwise when viewed from above, the cutting leaves are blown away to the left of the operator. become.

  When the mowing ground is an inclined land such as the bank of Kawahara, the operator performs the mowing operation while moving forward at almost the same height along the bank. When done, the foliage is blown away on the lower slopes. After moving forward to the end of the mowing area, the operator needs to return to the original position in order to carry out the mowing work in the area adjacent to the area already cut. This is because if the body is turned over and the adjacent region is cut without returning to the original position, the cut leaves are blown away to the higher side of the sloping ground in the opposite direction. For this reason, in order to blow all the foliage to the lower side of the slope, the operator needs to return to the original position, and there is a problem that workability is poor.

  The object of the present invention is to drive either the engine or the electric motor as a power source according to the usage environment and to blow the cutting leaves in either the left or right direction of the operator when driven by the electric motor. There is to do.

  A brush cutter according to the present invention includes a brush cutter body on which a cutter having a double-edged cutting blade is detachably connected to a tip end, and a driven shaft having a driven side connecting portion is rotatably attached to the cutter. An engine output having an electric motor that is detachably mounted on the main body of the dispenser and drives the cutter in both forward and reverse directions, and has a drive side connecting portion provided on the output shaft of the engine and connected to the driven side connecting portion. A driven side joint in which both the side joint and the motor side joint provided on the output shaft of the electric motor and incorporating the driving side connecting part connected to the driven side connecting part are detachably attached. A switching switch for switching the cutter driven by the electric motor between a normal rotation direction and a reverse rotation direction when the electric motor is mounted on the brush cutter main body. Characterized by detachably mounting the switch on the bush cutter body.

  The brush cutter according to the present invention is characterized in that the brush cutter main body is formed by a hollow bar-shaped operation arm into which a handle gripped by an operator is provided at a central portion in the longitudinal direction and the driven shaft is inserted.

  The brush cutter according to the present invention is characterized in that the changeover switch is connected to the electric motor via a cable and is provided in a holder that is detachably attached to the handle.

  According to the present invention, either the engine or the electric motor can be selectively attached to the brush cutter main body, and the engine and the electric motor are prepared as attachments, so that it can be used according to the usage environment in the mowing work. The brush cutter can be used as an engine driven type or a motor driven type. When the cutter is driven by an electric motor, a cutter having a cutting edge with a cutting edge formed in either the forward rotation direction or the reverse rotation direction is attached to the brush cutter body, and the cutter is moved in either forward or reverse direction. Can also be set to either the left or right direction. Therefore, for example, when an operator moves a weed that grows on an inclined land such as a bank of Kawahara along the bank, the mowing work is performed when the mowing work is performed with the lower left and when the mowing work is performed with the lower right. By reversing the direction of rotation of the cutter, the operator can perform the mowing work by continuously blowing the leaves toward the lowland side of the bank even if the body is inverted and the mowing work is continued. it can.

  According to the present invention, the brush cutter main body is formed by the operation arm provided with the handle, so that the operator can perform the cutting operation by grasping the handle and operating the operation arm. The changeover switch can be detachably attached to the handle by the holder, and by providing the changeover switch near the grip portion of the handle, the changeover switch can be operated with the handle held, and the workability is good.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a perspective view showing a brush cutter according to an embodiment of the present invention. FIG. 1 (A) shows a state in which an engine is mounted on a brush cutter body, and FIG. The state where the motor is mounted is shown. The brush cutter shown in FIG. 1 is of an arm connection type and has an operation arm 10 as a brush cutter body. The operation arm 10 is composed of a hollow rod-like member, and a driven shaft 11 is rotatably mounted inside (see FIGS. 2 and 4).

  A support member 12 is attached to the distal end portion of the operation arm 10, and a metal cutter 13 is rotatably attached to the support member 12, and the cutter 13 is attached to the distal end of the driven shaft 11 with a pair of bevel gears (not shown). ) Are detachably connected via a). As shown in FIG. 1, the cutter 13 is a disk-shaped metal blade provided with a plurality of chevron-shaped cutting blades 14, and the cutting blades 14 are provided with cutting edges on both the forward and reverse sides of the cutter 13. It is a formula. A cover 15 is attached to the tip of the operation arm 10 so as to cover the operator side of the cutter 13, thereby ensuring work safety.

  Two handles 16 are attached to the center of the operation arm 10 in the longitudinal direction, and the operator can lift and move the cutter 13 from the ground by holding the handle 16 with both hands. In the illustrated case, the brush cutter is a two-handed handle type in which two handles 16 are attached to the operation arm 10, but instead of this, a loop handle type may be used. It is also possible to attach a belt and make the brush cutter shoulder type.

  A driven side joint 17 is attached to the rear end portion of the operating arm 10 as a joint on the main body side of the brush cutter, and the operating arm 10 is a portion of the driven side joint 17, as shown in FIG. As shown in FIG. 1 (B), both the electric motor 19 and the electric motor 19 are selectively detachably mounted.

  2 is an enlarged sectional view showing a part of the brush cutter in FIG. 1 (A), FIG. 3 (A) is a front view of the engine, and FIG. 3 (B) is a view of the engine shown in FIG. It is a side view. The engine 18 is a four-cycle single-cylinder gasoline engine. A crankcase that rotatably supports an engine output shaft 21 including a crankshaft is incorporated in the engine cover 20, and a piston can reciprocate in the crankcase. An engine constituent member (not shown) such as a cylinder to be mounted on is installed. The engine output shaft 21 is provided with a recoil starter, and the engine 18 can be started by pulling the recoil knob 22. When the engine 17 is driven using gasoline in the fuel tank 23 as fuel, the cooling fan 24 attached to the engine output shaft 21 cools the engine 18.

  4 is an enlarged sectional view showing a part of the brush cutter in FIG. 1 (B), FIG. 5 (A) is a front view of the electric motor, and FIG. 5 (B) is the electric motor shown in FIG. It is a side view of a motor. The electric motor 19 has a substantially hexagonal columnar motor case 25, and a motor output shaft 26 made of an amateur shaft is rotatably supported by the motor case 25. A motor component (not shown) such as a fixed armature or a magnet facing the armature is incorporated. A rechargeable battery 27 such as a lithium ion battery is mounted on the outer periphery of the electric motor 19, and the electric motor 19 can be driven by electric power supplied from the battery 27.

  6A is a front view of the driven side joint, and FIG. 6B is a side view of the driven side joint shown in FIG. The driven joint 17 is formed in a cup shape having a larger diameter than the operation arm 10 and is attached to the rear end portion of the operation arm 10, and a square flange portion 28 is provided at the open end thereof. Fastening holes 28 a into which bolts 29 as fastening members are screwed are formed at the four corners of the flange portion 28.

  As shown in FIG. 3 (A), the engine cover 20 is provided with an engine output side joint 30 in which fastening holes 30a corresponding to the fastening holes 28a are formed. The engine 18 can be detachably mounted on the driven side joint 17 by screwing the bolts 29 into the fastening holes 28a, 30a in a state where the engine output side joint 30 is abutted. As shown in FIG. 5A, the motor case 25 is provided with a motor output side joint 31 having a fastening hole 31a corresponding to each of the fastening holes 28a, and is provided on the flange portion 28 of the driven side joint 17. The electric motor 19 can be detachably attached to the driven side joint 17 by screwing the bolts 29 into the fastening holes 28a, 31a in a state where the motor output side joint 31 is abutted. In addition, the code | symbol 32 shown in FIG. 2, FIG. 3 is a rubber-made sealing member.

  As shown in FIGS. 2 and 4, a clutch drum 33 that is fixed to the driven shaft 11 and rotates integrally with the driven shaft 11 is incorporated in the driven side joint 17. A driven side connecting portion is configured.

  As shown in FIG. 2, a pair of clutch shoes 35 provided at the tip of the engine output shaft 21 are incorporated in the engine output side joint 30, and a drive side connecting portion is configured by the clutch shoes 35. ing. As shown in FIG. 1A, when the engine 18 is mounted on the driven joint 17, the centrifugal clutch 36 is connected between the driven shaft 11 and the engine output shaft 21 by the clutch shoe 35 and the clutch drum 33. Composed.

  FIG. 7 is a cross-sectional view in FIG. As shown in FIG. 2, a disk-shaped rotating plate 37 is fixed to the engine output shaft 21, and as shown in FIG. 7, a clutch shoe 35 is swingably mounted on the rotating plate 37 by a pin 38. ing. A tension coil spring 39 is attached to each clutch shoe 35, and the tension coil spring 39 applies a spring force in a direction in which the friction contact portion 35 a is separated from the inner peripheral surface of the clutch drum 33 to each clutch shoe 35. It has been.

  Thus, when the engine 18 is started by pulling the recoil knob 22, the centrifugal clutch 36 is in an open state, and no great resistance is applied to the recoil knob 22, so that the engine 18 can be started easily. Furthermore, the clutch shoe 35 expands against the spring force of the tension coil spring 39 and is pressed against the inner peripheral surface of the clutch drum 33 by the centrifugal force that increases as the rotational speed of the engine 18 increases, and is connected to the clutch drum 33. Then, the engine output shaft 21 is directly connected to the driven shaft 11 via the centrifugal clutch 36, whereby the cutter 13 can be rotated via the driven shaft 11 to cut grass.

  A pair of clutch shoes 40 as drive side connecting portions are provided at the tip of the motor output shaft 26, and these clutch shoes 40 are incorporated in the motor output side joint 31, as shown in FIG. When the driven side joint 17 is fastened to the motor output side joint 31, the clutch shoe 40 and the clutch drum 33 constitute a centrifugal clutch 41 between the driven shaft 11 and the motor output shaft 26.

  As shown in FIG. 4, a disc-shaped rotating plate 42 is fixed to the motor output shaft 26, and a clutch shoe 40 is swingably mounted on the rotating plate 42 using a pin (not shown). Each clutch shoe 40 is provided with a tension coil spring 43, and the tension coil spring 43 applies a spring force in a direction in which the friction contact portion 40 a is separated from the inner peripheral surface of the clutch drum 33 to each clutch shoe 40. It has been.

  As a result, the clutch shoe 40 expands against the spring force of the tension coil spring 43 due to the centrifugal force that increases as the number of revolutions of the electric motor 19 increases, and is pressed against the inner peripheral surface of the clutch drum 33 to cause the clutch drum The motor output shaft 26 is connected to the driven shaft 11 via the centrifugal clutch 41 and can rotate the cutter 13 via the driven shaft 11 to cut grass. Further, when the cutter 13 stops rotating while the drive current is supplied from the battery 27 due to grass becoming entangled with the cutter 13, the motor output shaft 26 is moved by the slip of the clutch shoe 40 against the clutch drum 33. The motor continues to rotate, and an overcurrent is prevented from flowing through the electric motor 19. By controlling the electric power supplied to the electric motor 19, the rotation speed and the rotation direction of the motor output shaft 26 can be freely controlled.

  FIG. 8A is an enlarged perspective view showing a selector switch provided on the handle shown in FIG. 1B, and FIG. 8B is a circuit diagram showing a forward / reverse switching circuit of a motor having the selector switch. is there. A motor adjuster 46 having an adjustment dial 44 for controlling the motor rotation speed and a changeover switch 45 for switching the rotation direction is detachably mounted near the grip portion of the handle 16. The motor adjuster 46 has a holder 47 that is detachably attached to the handle 16, and in the illustrated case, the holder 47 has an attachment band 48 having a substantially C-shaped cross section. The notch 48a can be expanded. Bolts 49 are inserted into the notches 48a. After the handle 16 is fitted from the notches 48a, the bolts 49 are inserted into the notches 48a and fastened using the nuts 50. Thus, the motor adjuster 46 can be detachably attached to the handle 16. The motor adjuster 46 is connected to the control unit of the electric motor 19 via the cable 51. When the electric motor 19 is attached to the operation arm 10 as shown in FIG. The holder 47 is detachably attached to the handle 16. On the other hand, when the engine 18 is attached to the operation arm 10, the motor adjuster 46 is removed from the handle 16 as shown in FIG.

  A variable resistor (not shown) is incorporated in the adjustment dial 44, and the drive current supplied from the battery 27 to the electric motor 19 by changing the resistance value of the variable resistor by rotating the adjustment dial 44. The number of rotations of the electric motor 19 can be adjusted by changing. By adjusting the rotation speed of the electric motor 19, the rotation speed of the cutter 13 can be adjusted via the driven shaft 11.

  In the illustrated case, the changeover switch 45 is a push button type switch that switches between two positions, a position connected to the forward contact of the motor forward / reverse switching circuit and a position connected to the reverse contact. The position is held until the changeover switch 45 is pressed. When the changeover switch 45 is connected to the forward contact, the cutter 13 is driven to rotate in the forward direction indicated by an arrow N in FIG. 1B, for example, and when the changeover switch 45 is connected to the reverse contact, the cutter 13 is moved to the arrow R. As shown in FIG. Each rotation direction is held until the changeover switch 45 is pressed again. The shape and structure of the changeover switch 45 are not limited to those shown in the drawings, and any slide type, lever type, or rotational type can be used as long as the operator can switch the rotation direction of the electric motor 19 to both forward and reverse directions. A type of switch may be used.

  In such a brush cutter, the operating arm 10 can be mounted with the engine 18 to perform the cutting operation, and the operating arm 10 can be mounted with the electric motor 19 to perform the cutting operation. When the cutter 13 is driven to rotate by the electric motor 19 and the cutting operation is performed, the rotation direction of the cutter 13 can be changed to either forward or reverse by operating the changeover switch 45 with the fingertip while the handle 16 is held. Can be rotated.

  FIG. 9A is a plan view of a single-edged cutter, and FIG. 9B is a plan view of a double-edged cutter. As shown in FIG. 9A, the single-edged cutter 13a has a plurality of saw blades 14 on the outer periphery of a metal disk, and each of the cutting blades 14 rotates in the direction of the cutter 13a. The cutting edge 52 is formed on the front side and extends in the radial direction, and is formed on the rear side in the rotation direction and has an inclined surface 53. The inclined surface 53 is not formed with a cutting edge, and the cutting edge 52 rotates. It is formed only on one side in the direction. On the other hand, the double-edged cutter 13 is provided with a plurality of angle-shaped cutting blades 14 on the outer periphery of a metal disk, and each cutting blade 14 has cutting edges 52a, 52b is formed.

  Both the single-edged cutter 13a and the double-edged cutter 13 shown in FIG. 9 can be attached to the operation arm 10 to perform cutting work such as weeds using either the engine 18 or the electric motor 19 as a drive source. As shown in FIG. 1B, when the electric motor 19 is attached to the operation arm 10, a double-edged cutter 13 is attached so that the cutting operation can be performed regardless of which direction the cutter 13 is rotated. Can do. Even when the drive source is changed from the electric motor 19 to the engine 18 with the double-edged cutter 13 mounted on the operation arm 10, as shown in FIG. When the cutting operation can be performed by the engine 18, the cutting operation may be performed by the single-blade cutter 13a.

  FIG. 10 (A) is a schematic diagram showing a mowing procedure when a double-edged cutter 13 is mounted and a mowing operation is performed by a brush cutter using the electric motor 19 as a driving source. , 62 and front and rear edges 63, 64, when the cutting operation is performed from the area close to the right side 62 in FIG. Is rotated in the forward direction as indicated by the arrow N, the operator first returns the operating arm 10 to the right as indicated by the arcuate arrow and then swings it from the right to the left. The cutter 13 is moved from the right direction to the left direction to perform the cutting operation. After performing the mowing work by swinging the operation arm 10 in this manner, the operator moves forward along the side 62 and similarly returns the cutter 13 to the right, and then moves the cutter 13 to the left. Mowing is done by moving. Thus, the mowing operation proceeds by repeating the operation of swinging the operation arm 10 left and right and the forward movement of the operator.

  In this mowing operation, the cut leaves are blown off to the left side 61 in FIG. When the work has progressed to the end 63 on the work end side, the operator reverses the posture and operates the changeover switch 45 to switch the rotation direction of the cutter 13 to the reverse rotation direction. The cutter 13 is shown in FIG. In this way, mowing is performed when moving from the left side to the right side in the direction of travel. At this time, since the cutter 13 is reversed, the cut leaves are blown to the right in the traveling direction, so that the cut leaves are blown to the side 61 as in the case described above. Thus, in the case of performing the mowing work, the mowing work is performed both when moving forward from the work start side edge 64 toward the work end side edge 63 and when reciprocating when moving backward. Even if it performs, all the cuttings can be blown away to the one side 61 side.

  On the other hand, as shown in FIG. 10 (B), when a one-blade type cutter 13a is attached to a brush cutter to perform a cutting operation, the cutter 13a is rotated in the normal rotation direction to perform the cutting operation. Therefore, after moving from one end 64 side toward the turn-up end 63 and blowing off the cut leaves to the side 61, the area adjacent to the area after cutting In order to fly the cut leaves to the side 61 when the cut is cut, the cut leaves are blown to the side 62 when the cut is performed in reverse. Therefore, the operator needs to return to the position of the original start side edge 64 as indicated by the broken line, and can perform the mowing work only when returning.

  Accordingly, when the cutter 13 is rotated by the electric motor 19 to perform the cutting operation, the cutting leaves can be brought to one side by rotating the cutter 13 in both the forward and reverse directions. In particular, when the mowing is an inclined land such as a bank whose side 62 is high in FIG. 10, the operator can move the mowing leaves toward the lowland side during both reciprocating movements. Property is improved.

  The present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the scope of the invention. For example, the present invention can also be applied to a direct acting type brush cutter or a type of brush cutter in which a driving source and a cutter are mounted on a traveling carriage.

(A) shows a state where the engine is mounted on the brush cutter body, and (B) shows a state where the electric motor is mounted on the brush machine body. It is an expanded sectional view which shows a part of brush cutter shown in FIG. (A) is a front view of the engine, (B) is a side view of the engine shown in FIG. 3 (A). It is an expanded sectional view which shows a part of brush cutter shown in FIG.1 (B). (A) is a front view of an electric motor, (B) is a side view of the electric motor shown to FIG. 5 (A). (A) is a front view of a driven side joint, (B) is a side view of the driven side joint shown in FIG. 6 (A). It is a cross-sectional view in FIG. FIG. 2A is an enlarged perspective view showing a changeover switch provided on the handle shown in FIG. 1B, and FIG. 2B is a circuit diagram of the changeover switch. (A) is a top view of a single-edged cutter, and (B) is a plan view of a double-edged cutter. (A) is a schematic diagram showing a cutting operation procedure with a double-edged cutter, and (B) is a schematic diagram showing a cutting procedure with a single-edged cutter.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Operation arm 13 (double-blade type) cutter 13a (single-blade type) cutter 16 Handle 17 Driven side joint 18 Engine 19 Electric motor 30 Engine output side joint 31 Motor output side joint 45 Changeover switch

Claims (3)

A brush cutter main body on which a cutter having a double-edged cutting blade is detachably connected to the tip and a driven shaft having a driven side connecting portion is rotatably mounted; And an electric motor that drives the cutter in both forward and reverse directions,
An engine output side joint provided with an output shaft of the engine and connected to the driven side connecting portion, and a drive side provided with an output shaft of the electric motor and connected to the driven side connecting portion The brush cutter body is provided with a driven side joint that is selectively detachably attached to any of the motor side joints in which the connecting portions are incorporated,
A switch for switching the cutter driven by the electric motor between a normal rotation direction and a reverse rotation direction in a state where the electric motor is mounted on the brush cutter body is detachably mounted on the brush cutter body. Brush cutter characterized by.   2. The brush cutter according to claim 1, wherein the brush cutter body is formed by a hollow bar-shaped operating arm into which a handle gripped by an operator is provided at a central portion in a longitudinal direction and the driven shaft is inserted. Payment machine.   The brush cutter according to claim 2, wherein the changeover switch is provided in a holder that is connected to the electric motor via a cable and is detachably attached to the handle.

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