JP2013146241A - Electric bush cutter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electric bush cutter capable of preventing driving in a contracted state of an extension pipe by an inexpensive structure, and allowing for compact transport and storage.SOLUTION: Provided is an electric bush cutter including: an operation pole 20 having an expansion pipe 30 and a handle part 25; a motor 60 supported on opposite side of the handle part; a cutting blade 52 rotationally driven by the motor; a power supply 10, which is arranged on the handle part side of the operation pole 20, for supplying electric power to the motor; a switch for switching on/off the power supply to the motor; and a connection terminal pair consisting of connection terminals 40a, 40b wherein an on/off state changes according to the extension and contraction of the extension pipe 30 and an off-state is available when the extension pipe 30 is in a contracted state.

Description

  The present invention relates to an electric brush cutter having an extendable pipe for reducing the size during transportation and storage.

  In a conventional telescopic electric brush cutter that can be compacted during transportation and storage, the power supply unit (curl cord) curled between the power supply unit at the rear end and the drive unit at the front end that rotates the cutting blade is placed in the expansion pipe. Was connected through. In addition, there has been a telescopic engine brush cutter in which a switch is disposed at a connecting portion of the telescopic pipe (Patent Document 1 below).

Japanese Utility Model Publication 4-32902

  In the conventional telescopic electric brush cutter using the curl cord, it is necessary to use an expensive curl cord. In addition, an inexpensive curl cord has a problem that the curl cord expands due to repeated expansion and contraction. Furthermore, it is desirable that a predetermined distance or more be ensured between the operator and the cutting blade, but driving was possible even when the telescopic pipe was reduced.

  Further, since the telescopic engine brush cutter of Patent Document 1 uses a switch with an operation lever, if the switch with an operation lever fails in a closed circuit state, the engine may be driven at the time of reduction.

  An object of the present invention is to provide an electric brush cutter that solves the above problems, prevents the expansion pipe from being driven in a contracted state with an inexpensive structure, and can be made compact during transportation and storage.

  One embodiment of the present invention is an electric brush cutter. The electric brush cutter includes an operating rod having an extendable pipe and a handle portion, a motor supported on the side opposite the handle portion of the operating rod, a cutting blade driven to rotate by the motor, and a handle portion of the operating rod. A power supply unit that is disposed on the side and supplies power to the motor, and a connection terminal pair that is disposed on a current-carrying circuit from the power supply unit to the motor and that is in a non-contact state when the telescopic pipe is contracted. Prepare.

  In the above aspect, the telescopic pipe has a large-diameter pipe portion and a small-diameter pipe portion movable inside the large-diameter pipe portion, and a connection terminal is provided in each of the large-diameter pipe portion and the small-diameter pipe portion. The connection terminal pair is configured, and the connection terminal pair may be in a non-contact state in a state where the small-diameter pipe portion has a large amount of entering the inside of the large-diameter pipe portion.

  The said aspect WHEREIN: The said large diameter pipe part and the said small diameter pipe part have an uneven | corrugated fitting part extended in the expansion-contraction axial direction, and it is good for the said connecting terminal pair to be arrange | positioned at the said uneven | corrugated fitting part.

  In the above aspect, the concave / convex fitting portions may be provided on the outer circumferences of the large-diameter pipe portion and the small-diameter pipe portion at intervals of 180 degrees, and the connection terminal pairs may be disposed in the concave / convex fitting portions. .

  It should be noted that any combination of the above-described constituent elements, and those obtained by converting the expression of the present invention between methods and systems are also effective as aspects of the present invention.

  According to the electric brush cutter according to the present invention, since the connection terminal pair that is disposed on the energization circuit from the power supply unit to the motor and is in a non-contact state when the expansion pipe is contracted is used, an inexpensive structure is provided. Thus, it is possible to reliably prevent the motor drive when the telescopic pipe is contracted, and to make it compact during transportation and storage. In addition, since the motor can be driven only when one connection terminal forming the connection terminal pair and the other connection terminal are in contact with each other, there is no failure in a closed circuit state.

The side view which shows the whole structure of the electric brush cutter which concerns on embodiment of this invention. The A section expanded sectional view of FIG. The B section expanded sectional view of FIG. DD sectional drawing of FIG. The C section expanded sectional view of FIG. The circuit diagram which shows an electrical connection.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings. In addition, the same code | symbol is attached | subjected to the same or equivalent component, member, process, etc. which are shown by each drawing, and the overlapping description is abbreviate | omitted suitably. In addition, the embodiments do not limit the invention but are exemplifications, and all features and combinations thereof described in the embodiments are not necessarily essential to the invention.

  As shown in FIGS. 1 to 6, the cordless electric brush cutter includes a power supply unit 10, an operation rod 20, and a drive unit 50. The power supply unit 10 is provided on one side of the operation rod 20, and the drive unit 50 is provided on the other side.

  As shown in FIG. 2, the power supply unit 10 holds a battery 12 serving as a power source at the rear of the power supply unit housing 11, and is accommodated in the housing 11 and a main power switch (push button switch) 15 attached to the housing 11. The switch 13 and the controller 14 are provided. When the switches 13 and 15 are turned on (ON), the battery 12 and the motor 60 provided in the driving unit 50 can be connected to each other, and a connection terminal pair (a connection terminal 40a and a connection terminal 40b, which will be described later with reference to FIGS. And the voltage controlled by the controller 14 drives the motor 60 when the battery 12 is placed in a contact state between the battery 12 and the motor 60.

  As shown in FIG. 1, the operating rod 20 has a handle portion 25 and an extendable pipe 30. The switch 13 is turned on and off (ON / OFF) via a connecting member such as a wire 28 by operating a lever 27 provided rotatably in the handle 26 of the handle portion 25.

  The telescopic pipe 30 has a large-diameter pipe portion 31 fitted and fixed to the power source housing 11 and a small-diameter pipe portion 32 fitted and fixed to the drive housing 65 in which the motor 60 is incorporated. 3 and FIG. 4, the small diameter pipe portion 32 enters the large diameter pipe portion 31 and is connected and held by the holder 33. The large-diameter pipe portion 31 and the small-diameter pipe portion 32 are respectively formed with recesses 31b and 32b at intervals of 180 degrees as viewed from the outer peripheral side (that is, two with respect to the outer periphery of 360 degrees). Since it is formed in the telescopic axis direction (longitudinal direction), the small-diameter pipe 32 slides and expands inside the large-diameter pipe portion 31, but does not rotate with respect to the telescopic shaft 48. The holder 33 is fixed to the large-diameter pipe portion 31, and a fixing clamp 34 is integrally provided on the holder 33. When the fastening screw of the fixing clamp 34 (not shown in FIG. 3) is loosened, the expansion and contraction pipe 30 can be expanded and contracted. When the fastening screw of the fixing clamp 34 is tightened, the fixing clamp 34 can reduce the diameter of the pipe. The outer periphery of the part 32 can be fixed at a predetermined length by tightening and holding.

  As shown in FIGS. 3 and 4, one end of the power supply line 39a is connected to the connection terminal 40a, and the connection terminal 40a is connected to the inside by a pressing means to the inner side (not shown) from the hole 31a of the large-diameter pipe portion 31. It is arranged so that it can protrude slightly. The other end of the power supply line 39 a is connected to the controller 14 through the holder 33 and the handle 26.

  One end of the power supply line 39b is connected to the connection terminal 40b, and the connection terminal 40b is disposed so as to be slightly protruded outward from the hole 32a of the small-diameter pipe portion 32 by a pressing means to the outside (not shown). . The other end of the power line 39 b passes through the small diameter pipe portion 32 and is connected to the motor 60.

  In addition, when the large diameter pipe part 31 and the small diameter pipe part 32 are metal, it is necessary to provide an insulating member between them and the connection terminals 40a and 40b.

  The holes 31a of the large-diameter pipe part 31 are arranged at the bottom of the recesses 31b provided at the outer periphery at intervals of 180 degrees, and the holes 32a of the small-diameter pipe part 32 are arranged at the bottoms of the recesses 32b provided at the outer periphery at intervals of 180 degrees. Has been placed. A pair of connection terminals (a set of connection terminals 40a and 40b) provided in the holes 31a and 32a of one of the recesses 31b and 32b is used to turn on and off the + side connection, and the other recess 31b at a position rotated 180 degrees. A pair of connection terminals (a set of connection terminals 40a and 40b) provided in the hole portions 31a and 32a of 32b is used for turning on and off the negative side connection. Since the pipe portions 31 and 32 do not rotate with respect to the telescopic shaft 48, different connections on the + side and the − side of the connection terminal 40a and the connection terminal 40b are prevented during the expansion and contraction work.

As shown in FIG. 1, the telescopic pipe 30 is provided with a protective cover 38 that covers a part of the cutting blade 52 provided on the auxiliary handle 37 and the drive unit 50.
As shown in FIG. 5, the drive unit 50 has a motor 60 incorporated in the drive unit housing 65 and a cutting blade 52 fixed to the output shaft 62a. The motor 60 is a disk motor, and a stator 67 having a plurality of permanent magnets 61 and yokes 66 arranged and fixed in a ring shape in a housing 65, a rotor 62 on which coils are printed, and a commutator 63 integrated therewith. And a carbon brush 64 in contact with the commutator 63. The rotor 62 is rotatably supported with respect to the housing 65 by an output shaft 62a integrated therewith. The carbon brush 64 is held so as to contact the commutator 63 on the housing 65 side. The carbon brush 64 is connected to the power line 39b, and when the main power switch 15 is turned on, the connection terminal pair (a set of the connection terminal 40a and the connection terminal 40b) is in a contact state. The cutting blade 52 connected to the output shaft 62a is rotated by the voltage applied when 13 is turned on.

  In the above-described configuration, during the mowing operation, the expansion pipe 30 is set in the extended state of FIG. As a result, the connection terminal pair (a set of the connection terminal 40a and the connection terminal 40b) provided in the pipe portions 31 and 32 surrounded by the holder 33 is brought into a contact state, and the electrical connection between the controller 14 and the motor 60 in FIG. A connection is made. In order to maintain this state, the small diameter pipe portion 32 is fixed by tightening the fixing clamp 34 integrated with the holder 33. Then, the main power switch 15 is turned on so that the electric brush cutter can be used. Thereafter, by grasping the handle 26 and the auxiliary handle 37 and pulling the lever 27 provided on the handle 26, the switch 13 is operated to energize the controller 14 from the battery 12, and the telescopic pipe 30 is connected via the power lines 39a and 39b. The motor 60 is activated by supplying power to the motor 60 at the tip, and the cutting blade 52 is rotationally driven by the rotation to perform operations such as mowing.

  At this time, if the telescopic pipe 30 is contracted, that is, if it is not extended to the specified position, the connection terminal pair (the combination of the connection terminal 40a and the connection terminal 40b) is in a non-contact state and the power supply line 39a and the power supply line 39b are connected. As a result, the motor 60 is not driven.

  According to the present embodiment, the following effects can be achieved.

(1) Aside from the switch 13 for turning on / off the power supply to the motor 60, the on / off (contact, non-contact) state changes according to the expansion / contraction of the expansion / contraction pipe 30, and the expansion / contraction pipe 30 contracts. Since the connection terminal pair that is turned off in the state is provided, it is possible to reliably prevent the motor from being driven when the telescopic pipe is contracted. That is, the motor 60 can be energized only in a state where a predetermined distance or more is ensured between the worker and the cutting blade. Further, the telescopic pipe 30 can be transported and stored in a compact state.

(2) The connection terminals 40a and 40b may be provided on the large-diameter pipe portion 31 and the small-diameter pipe portion 32 of the telescopic pipe 30 to form the connection terminal pair, respectively, and can be configured with a simple structure at low cost.

(3) The large-diameter pipe portion 31 and the small-diameter pipe portion 32 have concave and convex fitting portions (concave portions 31b and 32b) extending in the telescopic axis direction. Therefore, there is no positional deviation in the rotational direction between the connection terminals 40a and 40b.
(4) Since the recesses 31b and 32b are provided at intervals of 180 degrees on the outer circumference of the large-diameter pipe portion 31 and the small-diameter pipe portion 32, and the connection terminals 40a and 40b are respectively disposed there, one connection terminal A sufficient distance between the pair of 40a and 40b and the other pair of connection terminals 40a and 40b can be secured.

  The present invention has been described above by taking the embodiment as an example. However, it is understood by those skilled in the art that various modifications can be made to each component and each processing process of the embodiment within the scope of the claims. By the way. Hereinafter, modifications will be described.

  In the embodiment, by forming one or both of the connection terminals 40a and 40b long in the direction of the telescopic axis, it is possible to set a wide range of the length of the telescopic pipe 30 in which the connection terminals 40a and 40b can contact each other. is there.

  Although the disk motor is illustrated as the motor 60, it is not limited to this.

DESCRIPTION OF SYMBOLS 10 Power supply part 11 Power supply part housing 12 Battery 13 Switch 14 Controller 20 Operation rod 25 Handle part 26 Handle 27 Lever 28 Wire 30 Telescopic pipe 31 Large diameter pipe 31a, 32a Hole part 31b, 32b Recess 32 Small diameter pipe 33 Holder 34 Fixing Clamp 37 Auxiliary handle 38 Protective cover 39a, 39b Power line 40a, 40b Connection terminal 48 Telescopic shaft 50 Drive unit 52 Cutting blade 60 Motor 61 Magnet 62 Rotor 63 Commutator 64 Carbon brush 67 Stator

Claims (4)

An operating rod having a telescopic pipe and a handle portion;
A motor supported on the side opposite the handle of the operating rod;
A cutting blade driven to rotate by the motor;
A power supply unit disposed on the handle unit side of the operating rod to supply power to the motor;
An electric brush cutter comprising: a connection terminal pair that is disposed on an energization circuit from the power supply unit to the motor and is in a non-contact state when the expansion pipe is contracted.   The expansion pipe has a large-diameter pipe portion and a small-diameter pipe portion that is movable inside the large-diameter pipe portion, and connection terminals are provided in the large-diameter pipe portion and the small-diameter pipe portion, respectively. 2. The electric brush cutter according to claim 1, wherein a terminal pair is configured and the connection terminal pair is in a non-contact state in a state in which the small-diameter pipe portion enters a large amount inside the large-diameter pipe portion.   The electric brush cutter according to claim 2, wherein the large-diameter pipe portion and the small-diameter pipe portion have an uneven fitting portion extending in a telescopic axis direction, and the connection terminal pair is disposed in the uneven fitting portion. .   The said uneven | corrugated fitting part is provided in the outer periphery of the said large diameter pipe part and the said small diameter pipe part at intervals of 180 degree | times, The said connection terminal pair is arrange | positioned at each uneven | corrugated fitting part. Electric brush cutter.

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