JPH077333U - Emergency cutting blade stop device for brush cutter - Google Patents

Abstract

(57) [Summary] [Purpose] The brush cutter 10 that stops the rotation of the cutting blade 20 in an emergency.
In the emergency cutting blade stop device, the maintenance is facilitated and the cutting blade 20 can be quickly stopped in an emergency. [Structure] The brush cutter 10 is already equipped with a battery 46 for operating an engine starting motor. The electromagnetic brake 38 is
It is provided on the proximal end side of the transmission shaft 18 that rotates in conjunction with the cutting blade 20, and the coil 42 is energized by the power of the battery 46 with the operation of the emergency stop switch 26 of the operating handle 12. ,
Braking the transmission shaft 18.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to an emergency cutting blade stop device for a brush cutter capable of stopping the cutting blade in an emergency.

[0002]

[Prior art]

 When cutting grass with a brush cutter, the cutting blade may collide with stones, rocks, etc., causing damage, and fragments may scatter around.In such a case, it is necessary to stop the cutting blade urgently. There is.

A mechanical friction brake is used for an emergency cutting blade stopping device of a conventional brush cutter (eg, Japanese Utility Model Laid-Open No. 51-67230 and Japanese Utility Model Laid-Open No. 59-95841).

[0004]

[Problems to be solved by the device]

 When the rotation of the cutting blade is stopped by the mechanical friction brake, the mechanical friction brake includes a motion mechanism such as a friction material, which makes maintenance troublesome. Also, the force that presses the friction material against the rotating part is generated by the operating force of the operator, so when the operator is in a hurry, a large operating force is not readily generated and the rotation stop of the cutting blade is delayed. .

An object of the present invention is to provide an emergency cutting blade stop device for a brush cutter that facilitates maintenance and can quickly stop the cutting blade in an emergency.

[0006]

[Means for Solving the Problems]

 The invention will be described using the reference numerals of the drawings corresponding to the embodiments. The emergency cutting blade stop device of the brush cutter (10) of the present invention has the following components (a) to (c). (A) Battery (46) that supplies power to the engine start motor (b) Electromagnetic brake (38) that stops rotation of the cutting blade (20) when energized (c) Operates the electromagnetic brake (38) by operating in an emergency Emergency stop switch (26) that is energized by the power of the battery (46)

[0007]

[Action]

 In an emergency where the cutting blade (20) is damaged, the operator immediately operates the emergency stop switch (26). As a result, electric power is supplied to the electromagnetic brake (38) from the battery (46) for operating the engine starting motor, the electromagnetic brake (38) is energized, and the cutting blade (20) is rotationally braked.

[0008]

【Example】

 The present invention will be described below with reference to the embodiments shown in the drawings. FIG. 1 is a structural diagram of the main part of the brush cutter 10. The operating rod 12 extends substantially linearly and has a power unit 14 attached to the upper end side. The power unit 14 is equipped with a small two-cycle engine 16, an engine starting motor (not shown), a battery 46 that supplies electric power to the engine starting motor, and the like. It is adapted to be transmitted to a cutting blade 20 (only the reference numeral is shown) on the tip end side of the operating handle 12 through a transmission shaft 18 penetrating therethrough. The antivibration grip 22 is fitted and fixed to a portion of the operating baffle 12 near the power unit 14, and the engine switch 24 and the emergency stop switch 26 are further provided at a portion of the operating baffle 12 on the tip side of the antivibration grip 22. Is installed. The engine switch 24 allows the ignition current of the small two-cycle engine 16 to be generated in the on position, and prohibits the ignition current from being generated in the off position. The emergency stop switch 26 prevents the switch part inside by opening the cover of the case 27 with the cover and normally operating the switch part carelessly.

A crankshaft 28 as an output shaft of the small two-cycle engine 16 has a flywheel 30 with a cooling fan fixed at an end thereof, and a centrifugal clutch 32 controls a connection between the flywheel 30 with a cooling fan and the transmission shaft 18. . The centrifugal clutch 32 is disposed inside the drum 34, which rotates integrally with the transmission shaft 18, and rotates integrally with the flywheel 30 with a cooling fan. It has a centrifugal pressure contact member 36 that expands outward and engages with the inner peripheral surface of the drum 34.

The electromagnetic brake 38 is arranged in the clutch case 48 together with the centrifugal clutch 32. In the electromagnetic brake 38, the circular conductive plate 40 is fixed to the transmission shaft 18 adjacent to the end surface of the drum 34 and has a larger diameter than the drum 34. The pair of magnetic poles 44 are arranged so as to have a narrow space between the pair of magnetic poles 44 and the circular conductive plate 40 so as to sandwich the circular conductive plate 40 from both sides, and generate a magnetic force as the coil 42 is energized. The emergency stop switch 26, the coil 42, and the battery 46 form a closed loop circuit, and when the emergency stop switch 26 is on, the coil 42 is energized by the power of the battery 46.

The operation of the embodiment will be described. In the event of an emergency in which the cutting blade 20 collides with stones, rocks, etc. during work such as mowing with the brush cutter 10, the operator opens the case 27 with the lid of the emergency stop switch 26 to open the lid. Immediately turn on the switch in case 27. As a result, the electric power of the battery 46 is transmitted to the coil 42 of the electromagnetic brake 38, the pair of magnetic poles 44 generate a large magnetic force, and the circular conductive plate 40 generates an eddy current in a direction that cancels the magnetic force of the magnetic pole 44. As a result, the centrifugal pressure contact member 36 is braked, and the cutting blade 20 quickly stops rotating via the transmission shaft 18.

[0012]

[Effect of device]

 The effects of this device are as follows. (A) The electromagnetic brake has no portion that is displaced when the cutting blade is rotationally braked, and therefore maintenance is simple. (B) Since the battery for energizing the electromagnetic brake in an emergency uses the one already installed for operating the engine starting motor, the addition of a new battery can be omitted. (C) The operator only needs to operate the emergency stop switch, and does not require the large operating force required to operate the mechanical friction brake, so even when the operator is in a hurry, the cutting blade The rotation can be stopped quickly.

[Brief description of drawings]

FIG. 1 is a structural diagram of a main part of a brush cutter.

[Explanation of symbols]

 10 Mower 20 Cutting blade 26 Emergency stop switch 38 Electromagnetic brake 46 Battery

Claims (1)

[Scope of utility model registration request] 1. A battery (46) for supplying electric power to an engine starting motor, (b) an electromagnetic brake (38) for stopping the rotation of the cutting blade (20) when energized, and (c) an emergency. An emergency stop switch (26) that is operated to energize the electromagnetic brake (38) with the power of the battery (46).
An emergency cutting blade stop device for a brush cutter, comprising: