JP2010200629A - Cord type bush cutter - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve the working efficiency and working accuracy of a cord type bush cutter. <P>SOLUTION: This cord type bush cutter has a cutter unit 30 equipped with a cord 32, an LED 50, cables 54, 56 for supplying electric power to the LED 50 and a centrifugal switch 60 for opening and closing the supplying pathway of the electric power supplied from a button type battery 52 and passing through the cables 54, 56. Here, the LED 50 is arranged to oppose to the fixed edge surface 320 of the cord 32. When a cutter unit 30 is rotated, the centrifugal switch 60 closes the electric power pathway consisting of the cables 54, 56 to supply the electric power for the LED 50. The LED 50 irradiates laser light to the fixed edge surface 320 of the cord 32 by being supplied with the electric power. The incident laser light from the fixed edge surface 320 is emitted to the outside of the cutter unit 30. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a cord type brush cutter including a light emitting unit.

As a tool for cutting weeds or the like, a cord type brush cutter is generally provided which is provided with a string of nylon or the like as a cutting blade and is cut by rotating the cutting blade. When the cord type brush cutter is used for a long time, the cutting blade is broken by abrasion. Even if the life of the cutting blade has expired due to cutting of the cutting blade due to wear, etc., the cord type brush cutter can be used for a long time by replacing only the cutting blade or the entire rotor connected to the cutting blade. used.
The cord type brush cutter disclosed in Patent Document 1 includes a cutting blade made of a biodegradable material such as polypropylene, and an end portion of the cutting blade is scattered around the cutting position by breakage due to abrasion. However, since it is decomposed by microorganisms or the like, it is considered to reduce the burden on the natural environment.

Japanese Patent Laid-Open No. 2003-230312

Cord type brush cutters are mainly used to cut the roots of weeds. In many cases, the upper part of the weed to be cut is bent. For this reason, weeds will be cut off mainly in the space behind the top of the weeds, and it is difficult to visually recognize the cutting blade. In particular, it is difficult to visually recognize the cutting blade during work in a place where it is not exposed to the sun or work at nightfall.
In order to improve the visibility of the cutting blade, a cord type brush cutter using a blade portion made of a fluorescent color material is generally used, but even if it is a fluorescent color, the visibility is improved when the blade portion is rotated at a high speed. It was difficult to keep good.
As described above, if it is difficult to visually recognize the cutting blade, an unintended portion may be trimmed off. Therefore, the operator must work carefully, and the work efficiency is low. In addition, when the setting at the time of the brush cutting range is fine, the brush cutting work is difficult and the work accuracy is low.

  Even if it is difficult to visually recognize the cutting blade, it is conceivable to perform the brushing work by predicting the length of the cutting blade. However, since the cutting blade of the cord type brush cutter disclosed in Patent Document 1 is broken by abrasion, the length varies. This makes it difficult for the operator to predict the length of the cutting blade.

  The present invention has been made in view of such problems, and an object thereof is to improve the work efficiency and work accuracy of a cord type brush cutter.

The cord type brush cutter according to the present invention is
A driving source;
A cord-like blade used as a cutting blade;
A rotating body that is rotatably provided by the drive source and holds the blade part;
A cord type brush cutter comprising:
A light emitting unit disposed inside the rotating body and irradiating light to the outside of the rotating body;
It is characterized by that.

For example, the light emitting unit irradiates light to one end of the blade unit,
It is preferable that the blade portion has translucency, and the light incident from the one end is propagated by the light emitting portion and emitted to the outside of the blade portion.

  Furthermore, it is preferable that the blade portion emits the light incident from one end surface of the blade portion from the other end surface of the blade portion.

Further, the blade portion has a diffusion material that diffuses the light,
The light emitted from the light emitting part may be incident from one end surface of the blade part, diffused by the diffusing material, and emitted from the peripheral surface of the blade part.

Further, the blade portion has a rough surface texture,
The light emitted from the light emitting part may be incident from the one end surface of the blade part, irregularly reflected on the surface of the blade part, and emitted from the peripheral surface of the blade part.

When the rotational speed of the rotating body is equal to or lower than a predetermined rotational speed, the power supply path to the light emitting unit is shut off,
It is preferable to further include a centrifugal switch that conducts the supply path of the power to the light emitting unit when the rotational speed of the rotating body exceeds a predetermined rotational speed.

  Moreover, it is preferable that the said blade part is formed from the synthetic resin which is colorless and transparent.

  According to the present invention, the work efficiency and work accuracy of a cord type brush cutter can be improved.

It is a side view which shows typically the cord type brush cutter concerning a 1st embodiment. It is side surface sectional drawing which shows typically the cutter unit of the cord type brush cutter which concerns on 1st Embodiment. It is a top view which shows typically the centrifugal switch provided in the cutter unit at the time of the non-working of the cord type brush cutter which concerns on 1st Embodiment. It is a top view which shows typically the centrifugal switch provided in the cutter unit at the time of the operation | work of the cord type brush cutter which concerns on 1st Embodiment. It is side surface sectional drawing which shows typically the cutter unit of the cord type brush cutter which concerns on 2nd Embodiment. It is an AA cross-sectional arrow view in FIG. 5 of the reel provided in the cutter unit of the cord type brush cutter according to the second embodiment.

  Hereinafter, embodiments of the present invention will be specifically described with reference to the accompanying drawings.

<First Embodiment>
As shown in FIG. 1, the cord type brush cutter 10 according to the first embodiment mainly includes a main body 20, a cutter unit 30, and an engine (drive source) 40.

  The main body 20 is formed in a cylindrical shape and includes a rotation shaft 200 therein. Further, a handle 22 held by the user is fixed to a part of the peripheral surface of the main body 20.

  The engine 40 produces rotational power of a crankshaft (not shown). The rotational power of the crankshaft is transmitted to a cutter unit 30 to be described later via a centrifugal clutch (not shown) and further via a rotary shaft 200 and a bevel gear (not shown) provided in the main body 20.

Next, the cutter unit 30 will be described in detail with reference to FIG. The cutter unit 30 is of a type that replaces the cord 32 having a predetermined length when the cord (cutting blade, blade portion) 32 wears out and becomes unusable.
The cutter unit 30 includes an upper case 300, a lower case 302 (the upper case 300 and the lower case 302 are also referred to as rotating bodies), a cord 32, an LED (light emitting diode, light emitting unit) 50, a button type battery 52, and a centrifugal switch 60 ( 3 and 4).

  On the lower case 302, two cords 32, two LEDs 50, and two button-type batteries 52, which will be described later, are placed.

  The cord 32 is colorless and transparent, and is made of nylon having translucency. The cord 32 is fixed by holding a fixed end face (one end face) 320 between the upper case 300 and the lower case 302 and preventing the cord 32 from coming off by a metal retaining bracket 34 provided on the outer periphery of the fixed end. The two are arranged symmetrically at the center of the cutter unit 30. As the cutter unit 30 rotates, a portion of the cord 32 that extends outside the case functions as a cutting blade.

  Two LEDs 50 are arranged in the cutter unit 30 so as to face the fixed end surfaces 320 of the two cords 32. The LED 50 is supplied with power from two button-type batteries 52 provided in the cutter unit 30 via cables (power supply paths) 54 and 56, and irradiates the fixed end surface 320 of the cord 32 with laser light.

  The upper case 300 is fixed to the rotary shaft 200 provided in the main body 20 by screwing the upper center 301 in the drawing. In addition to the two cords 32, two LEDs 50 and two button-type batteries 52 are also sandwiched between the upper case 300 and the lower case 302.

Next, the centrifugal switch 60 will be described with reference to FIGS.
The centrifugal switch 60 is mainly composed of a switch unit 61, an operation plate 62, a torsion spring 64, and a stopper 66.

  The switch unit 61 is connected to the LED 50 via a cable 56, and opens and closes the power supply path of the cable 56 according to the operation of an operation plate 62 described later.

  The operation plate 62 is disposed such that one end 620 faces the switch unit 61. A central portion 624 at substantially the center of the operation plate 62 is rotatably supported by the lower case 302. The mass on the one end 620 side from the central portion 624 is made lighter than the mass on the other end 622 side from the central portion 624. For this reason, the centrifugal force is greatly applied to the other end 622 side of the operation plate 62. Accordingly, when the cutter unit 30 rotates, the operation plate 62 rotates around the central portion 624 so that the other end 622 side is away from the center of the cutter unit 30.

  The torsion spring 64 has one end fixed to the stopper 66 and the other end fixed to one end 620 of the operation plate 62. The torsion spring 64 is urged by a predetermined elastic force so that the one end 620 of the operation plate 62 moves away from the center of the cutter unit 30 (the other end 622 of the operation plate 62 approaches the center of the cutter unit 30). Yes. In other words, the torsion spring 64 is biased in a direction to suppress the rotation of the operation plate 62 when the cutter unit 30 rotates.

Next, the operation of the cord type brush cutter 10 according to the present embodiment will be described.
When the engine 40 is operated and the rotational speed of the crankshaft (not shown) exceeds a predetermined value, the centrifugal clutch (not shown) transmits the rotational power of the crankshaft to the rotary shaft 200.

  When rotational power is transmitted to the rotating shaft 200, the rotational speed of the cutter unit 30 with the upper case 300 fixed to the rotating shaft 200 increases.

  When the rotational speed of the cutter unit 30 increases and exceeds the predetermined rotational speed, the operation plate 62 of the centrifugal switch 60 rotates counterclockwise in the drawing around the central portion 624 and presses the switch portion 61. .

  When the switch unit 61 is pressed by the operation plate 62, the power supply path to the LED 50 of the cable 56 is closed. When the power supply path is closed, the two LEDs 50 respectively irradiate the fixed end surfaces 320 of the two opposing cords 32 with laser light. The two cords 32 propagate laser light incident on the fixed end surface 320 from the LED 50 and emit the laser light from the free end surface (other end surface) 322.

  In the state where the cutter unit 30 is rotating, the cord 32 is brought into contact with the weeds or the like to be trimmed while emitting the laser beam, and cuts the weeds or the like.

  The operator can perform the brushing work while checking the position of the cord 32 by looking at the laser beam. In particular, at this time, a large amount of laser light is emitted from the free end surface 322 of the cord 32 which is the outermost contour of the trimming range, so it is easy to confirm the trimming range.

As described above, in order to check the trimming range of the cord 32, the laser beam may be emitted from the free end surface 322 of the cord 32. However, the method of emitting the laser beam is not limited to this. Laser light may be emitted from the free end surface 322 and the peripheral surface 324 of the cord 32 by using the cord 32 having a rough surface 324.
Furthermore, the light may be emitted from the peripheral surface 324 by containing a light diffusing substance (for example, metal powder) in the cord 32.

  Although the centrifugal switch 60 in the above embodiment has been described as closing the power supply path when the rotation of the cutter unit 30 reaches a predetermined number of rotations or more, the rotational power is transmitted from the rotary shaft 200 to the cutter unit 30 and the power supply path is turned off. The elastic force of the torsion spring 64 and the center of gravity (centrifugal force) of the operation plate 62 may be set so as to be closed. By doing so, the laser beam can be emitted from the cord 32 instantaneously at the time of work.

<Second Embodiment>
Next, a cutter unit 70 according to the second embodiment will be described with reference to FIGS. 5 and 6. FIG. 5 is a side cross-sectional view schematically showing the cutter unit 70, and FIG. 6 is a cross-sectional view taken along the line AA of FIG.
The cutter unit 30 according to the first embodiment described above is a type that replaces the cord 32 having a predetermined length when the service life of the cord 32 drawn from the cutter unit 30 is reached. In the cutter unit 70 according to this embodiment, the cord 32 is wound around a reel 72 described later, and the wound cord 32 can be pulled out from the reel 72 when the drawn cord 32 reaches the end of its useful life. It is a type that can. This type of cutter unit 70 replaces only the reel 72 when the portion where the cord 32 is wound is lost. Hereinafter, the cutter unit 70 will be described.
The cutter unit 70 mainly includes an upper case 700, a lower case 702, a reel 72 (the upper case 700, the lower case 702, and the reel 72 are also referred to as a rotating body), a cord 32, an LED 50, a dry battery 53, and a centrifugal switch 60. The

A reel 72 described later is disposed on the lower case 702.
The reel 72 includes an upper reel 72a and a lower reel 72b that are each formed in a bobbin shape and are integrally formed vertically. A cord 32a, which will be described later, is wound around the upper reel 72a, and a cord 32b, which will be described later, is wound around the lower reel 72b.
In the reel 72, cables 54 and 56 that electrically connect an LED 50, which will be described later, and the centrifugal switch 60 and the dry battery 53, are disposed through the inside.
Inside the center of the reel 72, there are provided a protrusion 722 and a compression spring 74 that is disposed between the protrusion 722 and the lower surface of the upper case 700 described later and biases the reel 72 downward in the drawing.
Locking portions 724 are respectively provided at portions where the reel 72 and the lower case 702 come into contact with each other. The operation of the locking portion 724 will be described later.
A reel cover 720 is fitted to the lower end of the reel 72. A dry battery 53 and a centrifugal switch 60 are accommodated in a space between the reel 72 and the reel cover 720.

The cord 32 is made of translucent nylon and includes a cord 32a wound around the upper reel 72a and a cord 32b wound around the lower reel 72b.
The fixed end faces 320a and 320b (see FIG. 6) of the cords 32a and 32b are fixed to the two cord pressers 76a and 76b, respectively. Further, the two cord pressers 76a and 76b are fixed to the reel 72 by fixing screws 78a and 78b.

  As shown in FIG. 6, the two LEDs 50 are arranged so as to face the fixed end faces 320a and 320b of the cords 32a and 32b, respectively. The two LEDs 50 are fixed to the two cord pressers 76a and 76b, respectively, like the cords 32a and 32b. The LED 50 is supplied with electric power from the two dry batteries 53 provided in the space between the reel 72 and the reel cover 720 via the cables 54 and 56, and transmits laser light to the fixed end faces 320a and 320b of the cords 32a and 32b. Irradiate.

The upper case 700 is fitted to the lower case 702, and the upper center 701 in FIG. 5 is screwed to the rotating shaft 200 provided in the main body 20 (see FIG. 1) and fixed.
Further, the cutter unit 70 is provided between the upper case 700 and the lower case 702, has a through hole, and includes a restricting portion 704 that restricts the operation of the cord 32.

  The operation of the cutter unit 70 according to this embodiment will be described with reference to FIGS. 1, 5, and 6.

  In the cutter unit 70 according to the present embodiment, when rotational power is transmitted from the engine 40 to the rotary shaft 200, the rotational speed of the cutter unit 70 having the upper case 700 fixed to the rotary shaft 200 increases.

  When the rotational speed of the cutter unit 70 increases and exceeds the predetermined rotational speed, the operation plate 62 of the centrifugal switch 60 presses the switch portion 61.

  When the switch unit 61 is pressed by the operation plate 62, the power supply path to the LED 50 of the cable 56 is closed. When the power supply path is closed, the two LEDs 50 irradiate laser light onto the fixed end faces 320a and 320b of the two opposing cords 32a and 32b, respectively. The two cords 32 propagate the laser light incident on the fixed end faces 320a and 230b from the LED 50, and exit from the free end faces 322a and 322b.

  In the state where the cutter unit 30 is rotating, the cord 32 is brought into contact with the weeds or the like to be trimmed while emitting the laser beam, and cuts the weeds or the like.

The operator can perform the brushing work while checking the position of the cord 32 by looking at the laser beam. In particular, at this time, a large amount of laser light is emitted from the free end surface 322 of the cord 32 which is the outermost contour of the trimming range, so it is easy to confirm the trimming range.
As described above, in order to check the trimming range of the cord 32, the laser beam may be emitted from the free end surface 322 of the cord 32. However, the method of emitting the laser beam is not limited to this. Laser light may be emitted from the free end surface 322 and the peripheral surface 324 of the cord 32 by using the cord 32 having a rough surface 324.
Furthermore, the light may be emitted from the peripheral surface 324 by containing a light diffusing substance (for example, metal powder) in the cord 32.
The cutter unit 70 also presses the lower surface of the reel cover 720 against the ground or the like when the cord 32 is shortened due to wear of the cord 32 due to aging, etc. Can be put out for a long time.

  Briefly describing this mechanism, when the rotational power of the rotary shaft 200 is transmitted to the upper case 700, the lower case 702 fitted to the upper case 700 and the reel 72 locked to the lower case 702 rotate integrally. To do. In this state, when the lower surface of the reel cover 720 is pressed against the ground or the like, the reel 72 moves upward against the downward biasing of the compression spring 74, and the locking of the locking portion 724 is released. Then, a difference occurs in the relative rotational speed between the reel 72 and the upper case 700 and the lower case 702, and the cords 32a and 32b are pulled out by a predetermined amount.

  In this way, even if the cord 32 is shortened due to wear or the like, if the cord 32 is wound around the reel 72, the cord 32 can be easily removed by pressing the lower surface of the reel cover 720 against the ground or the like. 72. Further, when there is no more portion wound around the reel 72, the cutter unit 70 can be used again by newly replacing the cord 32 or replacing each reel 72.

  In the cutter unit 70 according to the second embodiment, similar effects are obtained by attaching the LED 50 so as to face the fixed end faces 320a and 320b of the cord 32, similarly to the cutter unit 30 according to the first embodiment. be able to.

  Since the cord type brush cutter 10 and the cutter units 30 and 70 according to the embodiment are provided with the LED 50 inside and emit laser light through the cord 32, the visibility of the cord 32 is improved. As a result, work efficiency and work accuracy can be improved.

  Further, by allowing light from the LED 50 to enter the fixed end surface 320 of the cord 32 and emitting laser light from the free end surface 322, it is possible for the operator to easily view the outermost contour of the brushing range.

  Further, by allowing the cord 32 to contain a diffusing material that diffuses light and emitting laser light from the peripheral surface 324 of the cord 32, it is possible for the operator to easily see the trimming range as a whole.

  Further, by making the peripheral surface of the cord 32 have a rough surface property and similarly emitting laser light from the peripheral surface 324 of the cord 32, it is possible for the operator to easily view the entire trimming range.

  Furthermore, when the cutter units 30 and 70 exceed a predetermined number of rotations, a centrifugal switch 60 is provided to connect the power supply path to the LED 50, so that the cord type brush cutter 10 can automatically perform the brush cutting operation. Laser light is emitted from the cord 32, and workability can be improved.

  In addition, by forming the cord 32 with a colorless and transparent synthetic resin having good translucency, the laser light can be emitted from the cord 32 to the outside satisfactorily.

  The battery used in the first embodiment has been described as the button-type battery 52, and the battery used in the second embodiment has been described as the dry battery 53. However, it is sufficient that power can be supplied to the LED 50, and the form of the battery is not limited. For example, batteries that are opposite to each other may be used.

  Although the cord in the above embodiment has been described as being made of colorless and transparent nylon, it may be formed of other materials or may be colored as long as it has translucency.

  In addition, a cord composed of a plurality of layers having a layer with a high refractive index of light on the outer layer (that is, a configuration similar to that of an optical fiber used for communication) is adopted, and emission of light from the side surface of the cord is suppressed. A large amount of light may be emitted from the free end surface.

10: Cord type brush cutter 30, 70: Cutter unit 300, 700: Upper case (rotating body)
302, 702: Lower case (rotating body)
32, 32a, 32b: Cord (cutting blade, blade)
320, 320a, 320b: fixed end face (one end face)
322, 322a, 322b: free end face (other end face)
324, 324a, 324b: peripheral surface 40: engine (drive source)
50: LED (light emitting diode, light emitting part)
52: Button type battery 53: Dry cell 54, 56: Cable (power supply path)
60: Centrifugal switch 72: Reel 76a, 76b: Cord presser

Claims (7)

A driving source;
A cord-like blade used as a cutting blade;
A rotating body that is rotatably provided by the drive source and holds the blade part;
A cord type brush cutter comprising:
A light emitting unit disposed inside the rotating body and irradiating light to the outside of the rotating body;
Cord type brush cutter characterized by that. The light emitting part irradiates light to one end of the blade part,
The blade portion has translucency, propagates light incident from the one end by the light emitting portion, and emits the light to the outside of the blade portion.
The cord type brush cutter according to claim 1. The blade portion emits the light incident from one end surface of the blade portion from the other end surface of the blade portion,
The cord type brush cutter according to claim 1 or 2. The blade portion has a diffusion material that diffuses the light,
The light emitted from the light emitting part is incident from one end surface of the blade part, diffused by the diffusion material, and emitted from the peripheral surface of the blade part,
The cord type brush cutter according to any one of claims 1 to 3. The blade has a rough surface texture,
The light emitted from the light emitting portion is incident from the one end surface of the blade portion, is irregularly reflected on the surface of the blade portion, and is emitted from the peripheral surface of the blade portion.
The cord type brush cutter according to any one of claims 1 to 4. When the rotational speed of the rotating body is equal to or lower than a predetermined rotational speed, the power supply path to the light emitting unit is shut off,
When the rotational speed of the rotating body exceeds a predetermined rotational speed, further comprising a centrifugal switch for conducting the supply path of the power to the light emitting unit,
The cord type brush cutter according to any one of claims 1 to 5. The blade portion is formed of a synthetic resin that is colorless and transparent,
The cord type brush cutter according to any one of claims 1 to 6.

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