JP5265397B2 - Power tool switch - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve a problem wherein a switch of a power tool, which includes a lock-on mechanism for locking a switch lever of the power tool into its ON position and a lock-off mechanism for locking the switch lever into its OFF position, occasionally enters the lock-on state even without a user's intention because the switch is conventionally operated in the same direction to release the lock-off mechanism and to activate the lock-on mechanism, and to make the user enable to clearly distinguish between the operations of the two mechanisms and the switch enable to reliably reflect the user's operational intention. <P>SOLUTION: The switch is configured such that different operation members are used to release the lock-off state and to enter the lock-on state, thereby preventing the user from unintentionally perform the two operations continuously. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

  The present invention relates to a switch for starting a hand-held disc grinder used for, for example, stone processing.

For example, the above-mentioned hand-held disc grinder includes a main body portion that includes an electric motor as a drive source, a gear head that is assembled to the front portion of the main body portion, and a handle portion that is assembled to the rear portion of the main body portion.
A gear train for decelerating the rotational output of the electric motor is incorporated in the gear case of the gear head. The rotation output decelerated by the gear train is output to the spindle. A circular grindstone (disk) is mounted on this spindle.
The handle portion is a portion that is held by the user of the power tool with one hand, and a switch lever that the user pulls or slides between an on position and an off position with a fingertip is provided below the handle portion. For example, when the user holds the handle portion and moves the switch lever to the on position by, for example, pulling the switch lever with the fingertip (operation for grasping the handle portion), the power supply circuit is turned on and the electric motor of the main body portion is activated. When the electric motor is started, the rotation output is output to the spindle through the drive head, and the grindstone rotates. When the pulling operation of the switch lever is released, the switch lever is returned to the off position by, for example, a spring biasing force and the power supply circuit is shut off, so that the electric motor stops.
As for a switch including such a switch lever, a switch on which a lock-on mechanism for locking the switch lever in an on position and a lock-off mechanism for locking the switch lever in an off position are provided. According to the lock-on mechanism, even if the user does not hold the switch lever in the pulled state, the switch lever is held in the ON position and the electric motor is locked in the activated state. The workability of the electric tool (usability of the switch) can be improved. On the other hand, according to the lock-off mechanism, since the switch lever is locked in the off position and cannot be moved to the on position even if the user pulls it, the electric motor is inadvertently activated. Is prevented.
As a lock operation member for switching the lock-on mechanism and the lock-off mechanism, there is a structure using the movement of the switch lever itself, or a structure using a lever or a push button provided separately from the switch lever. Is provided. A technique related to the former configuration is disclosed in, for example, Patent Document 1 below, and a technique related to the latter structure is disclosed in, for example, Patent Document 2 below.

German patent DE3638952C2 Japanese Patent No. 2970776

However, according to the conventional switch having both the lock-on mechanism and the lock-off mechanism, the operation direction for releasing the lock-off mechanism and the operation direction for enabling the lock-on mechanism are substantially the same. Therefore, depending on the user, both operations are easily performed as a series of operations.
For this reason, the user intends to release only the lock-off state when attempting to use the power tool after releasing the state in which the switch lever cannot be moved to the on position (lock-off state) by the lock-off mechanism. Even if it is, even the lock-on mechanism may be operated and the switch lever may be locked in the on position.In this case, even if the user stops pulling the switch lever to stop the power tool, The power tool is maintained in the activated state. Thus, conventionally, there has been a problem that it is difficult to clearly reflect the user's intention between the operation of releasing the lock-off state and the operation of switching to the lock-on state.
The present invention has been made in view of the conventional problems, and in a switch including both a lock-off mechanism and a lock-on mechanism, the user's will regarding the operation for releasing the lock-off state and the switching operation to the lock-on state. The purpose is to ensure that these are clearly reflected.

Said subject is solved by each following invention.
According to a first aspect of the present invention, there is provided a switch lever capable of moving between an on position for starting and stopping an electric tool, a lock-on mechanism for locking the switch lever to an on position, and an off position of the switch lever. The switch is provided with a lock-off mechanism for locking, and an operation for enabling the lock-on mechanism and an operation for releasing the lock-off mechanism are performed by different operation members.
According to the first aspect, since the operation for enabling the lock-on mechanism and the operation for releasing the lock-off mechanism are performed by different operation members, the user releases the lock-off state. And the operation for enabling the lock-on mechanism can be clearly distinguished. For this reason, the lock-off state (the state where the lock-on mechanism is functioning) is not unconsciously switched to the lock-on state (the state where the lock-on mechanism is functioning) in accordance with the operation for releasing the lock-off state (the state where the lock-off mechanism is functioning). The will of the user is clearly reflected in the operation of the lock operation member.
A second invention is a switch according to the first invention, wherein the switch lever is moved and operated in a direction intersecting the operation direction between the on position and the off position to release the lock-off mechanism.
According to the second invention , the switch lever is slid forward, for example, to release the lock-off state, and the switch lever can be moved to the on position by grasping the switch lever in a direction crossing the sliding direction. Therefore, the lock-off releasing operation and the on-operation can be quickly performed as a continuous operation, and the operability (usability) of the switch can be improved in this respect. Even in this case, since it is necessary to operate an operation member provided separately from the switch lever in order to switch to the lock on state, the lock lever is clearly distinguished from the lock lever release operation and the on operation. An on operation is performed.
A third invention is the switch according to the first invention, wherein the lock-on mechanism is made effective by operating a lock-on operation member provided separately from the switch lever.
According to the third invention , the lock-on mechanism can be made effective by operating a lock-on operation member provided separately from the switch lever. Therefore, the user's intention is clearly reflected because the lock-on operation is clearly distinguished from the operation of the switch lever in order to release the lock-off mechanism.
Although different from the second and third inventions described above, a lock-off release operation member and a lock-on operation member may be provided separately from the switch lever. Even in this case, the operation for releasing the lock-off state, the operation for moving the switch lever to the ON position, and the operation for locking the ON position are performed as separate operations. The operation of releasing the mechanism and the operation of enabling the lock-on mechanism are prevented from being performed as a series of operations, and therefore the user's intention to operate can be clearly reflected.

It is a whole side view of an electric tool provided with a switch concerning an embodiment of the present invention. In this figure, a disc grinder is shown as an electric tool. It is a longitudinal cross-sectional view of the handle part provided with the switch of this embodiment. This figure shows the lock-off state. It is a longitudinal cross-sectional view of the handle part provided with the switch of this embodiment. This figure shows a state in which the lock lever is released and the switch lever is tilted to the on position. It is a longitudinal cross-sectional view of the handle part provided with the switch of this embodiment. This figure shows the lock-on state. It is a disassembled perspective view of the switch of this embodiment. In the figure, only the switch base and the switch lever are shown.

Next, an embodiment of the present invention will be described with reference to FIGS. FIG. 1 shows an electric tool 1 including a switch 10 according to the present embodiment. The electric tool 1 is a hand-held disc grinder, and includes a tool main body 2, a gear head 3, and a handle portion 4. A gear head 3 is coupled to the front portion of the tool body portion 2 and a handle portion 4 is integrally provided at the rear portion.
An electric motor 5 is built in the tool body 2. The rotational output of the electric motor 5 is output to the spindle 7 after being decelerated by the gear train 6 built in the gear head 3. A circular grindstone 8 is attached to the tip of the spindle 7.
The handle portion 4 mainly includes a handle case 4a having a thickness and a length that can be easily grasped by a user with one hand, and extends rearward from the rear portion of the tool main body portion 2. A power supply cord 9 for supplying power is drawn into the rear end portion of the handle portion 4. The electric motor 5 of the tool body 2 is activated using the power supplied from the power cord 9 as a power source.
The switch 10 of the present embodiment is provided on the lower surface side of the handle portion 4. Details of the switch 10 of this embodiment are shown in FIGS. The switch 10 is turned on and off by the switch base 19 fixed inside the handle case 4a, the switch lever 11 supported so as to be tiltable up and down with respect to the switch base 19, and the operation of the switch lever 11. The switch body 12 is provided.
The switch body 12 is attached in a state of being sandwiched between the switch base 19 and the handle case 4a, and is provided in the center of the handle case 4a. The operating knob 12a of the switch body 12 is directed downward (on the switch lever 11 side) through a window portion 19a provided at substantially the center of the switch base 19. The switch body 12 is turned on when the operation knob 12a is pushed upward, and turned off when the operation knob 12a is protruded downward by a spring biasing force. When the switch body 12 is turned on, a power supply circuit for starting the electric motor 5 is turned on. When the switch body 12 is turned off, the electric motor 5 is stopped. The switch body 12 and the power supply circuit are known techniques, and no particular changes are required in this embodiment.
The present embodiment is characterized by a switch lever 11 for turning on and off the switch body 12 and a lock-on mechanism and a lock-off mechanism for regulating the operation of the switch lever 11.

The switch lever 11 is supported in a state of extending in the front-rear direction generally along the lower portion of the switch base 19. The rear portion of the switch lever 11 is coupled to the rear portion of the switch base 19 via the support shaft 14 so that the switch lever 11 can be tilted up and down. The support shaft 14 is inserted into a long slot 11b that is long at the front and rear provided at the rear portion of the switch lever 11. Therefore, the switch lever 11 can be tilted up and down around the support shaft 14 and can be slid in a predetermined range in the front-rear direction.
A pair of left and right restricting arm portions 11 c and 11 c are provided on the left and right side portions on the front side of the switch lever 11. Both regulating arm portions 11c, 11c extend upward in a state of being parallel to each other. Engaging claws 11d are provided on the upper end portions of the restricting arm portions 11c and 11c, respectively. On the other hand, at the front portion of the switch base 19, two insertion groove holes 19b and 19b are provided corresponding to the restriction arm portions 11c and 11c. Both the insertion groove holes 19b, 19b are formed in parallel with each other and long in the front-rear direction. The restricting arm portions 11c and 11c of the switch lever 11 are respectively inserted into the insertion groove holes 19b and 19b from the lower side to the upper side, and the switch lever 11 is assembled to the switch base 19. By engaging the engaging claws 11d and 11d of the restricting arm portions 11c and 11c with the upper surface of the switch base 19, respectively, the withdrawal of the restricting arm portions 11c and 11c from the insertion groove holes 19b and 19b is restricted. Yes.
The switch lever 11 can be tilted up and down with respect to the switch base 19 within a range in which both the restricting arm portions 11c and 11c can advance and retract in the insertion groove hole 19b. Further, the switch lever 11 can be slid back and forth with respect to the switch base 19 within a range in which both the restricting arm portions 11c and 11c can move within the insertion groove hole 19b.
Two compression springs 13 and 18 (not shown in FIG. 5) are interposed between the switch lever 11 and the switch base 19. The switch lever 11 is urged in a direction tilting toward the lower OFF position (the direction opposite to the arrow C direction) by the compression spring 13 interposed in the vertical direction. The switch lever 11 is urged in a direction (a direction opposite to the arrow A direction) to slide toward the lock-off position on the rear side by a compression spring 18 interposed in the front-rear direction.

The switch lever 11 is provided with a lock-on mechanism and a lock-off mechanism. The lock-on mechanism has a function of locking the switch lever 11 in the on position, and the lock-off mechanism has a function of locking the switch lever 11 in the off position. Both mechanisms are released from the lock-off state and are switched to the lock-on state by operating different operation members. In this embodiment, the unlocking operation of the lock-off mechanism is performed by sliding the switch lever 11, and switching to the lock-on state is performed by operating a lock-on operation member 15 described later.
The lock-on operation member 15 is supported on the front side of the switch lever 11. A tip end portion 15 b of the lock-on operation member 15 is projected downward through a window portion 11 a provided on the lower surface of the switch lever 11. The lock-on operation member 15 is supported so as to be tiltable back and forth via a support shaft portion 15a. The lock-on operation member 15 is urged by the torsion spring 16 in the counterclockwise direction in FIG. 2 and displaces the tip 15b rearward (lock-on release position side). An engagement arm portion 15 c is integrally provided at the front portion of the lock-on operation member 15. The engagement arm portion 15c extends upward. A lock-on claw 15d is integrally provided on the upper portion of the engagement arm portion 15c. This lock-on claw 15d is provided in a state of projecting to the rear side.
Corresponding to the engagement arm portion 15 c, a lock arm 17 is integrally provided at the front portion of the switch base 19. The lock arm 17 is provided so as to extend downward from the lower surface of the switch base 19. A lock claw 17 a is integrally provided at the front lower portion of the lock base 17.

According to the switch 10 of this embodiment configured as described above, when the user does not operate the switch lever 11 as shown in FIG. 2, the switch lever 11 is moved downward by the urging force of the compression spring 13. It is located at the off position and is located at the rear lock-off position by the urging force of the compression spring 18. When the switch lever 11 is in the off position, the lock-on operation member 15 is held at the lock-on release position in which the tip end portion 15b is displaced rearward by the biasing force of the torsion spring 16.
In the initial state where the lock-on operation member 15 is located at the lock-on release position, the lock arm 17 is located directly above the engagement arm portion 15c. Therefore, in this lock-off position, even if the switch lever 11 is tilted to the on-position side (upward) at the rear-side lock-off position, the upward displacement of the engagement arm portion 15 c is restricted by the lock arm 17. Therefore, the switch lever 11 cannot be tilted to the on position side (the direction indicated by the white arrow C in FIG. 3) (lock-off state). This lock-off state prevents an inadvertent on operation of the switch lever 11.
On the other hand, as shown in FIG. 3, when the switch lever 11 is slid in the direction indicated by the white arrow A against the compression spring 18, the engagement arm portion 15 c is retracted to the front side with respect to the lock arm 17. Therefore, the switch lever 11 can be tilted to the on position side (arrow C direction) (lock-off release state). After releasing the lock-off state in this way, when the switch lever 11 is strongly held and tilted to the ON position side (in the direction of the white arrow C) as it is, the operation knob 12a is pushed in and the switch body 12 is turned on. The electric motor 5 is activated.
When the user stops the tilting operation of the switch lever 11 to the on position side by the fingertip, the switch lever 11 is returned to the lower off position by the compression spring 13. After the switch lever 11 is returned to the OFF position, when the user further releases the sliding operation to the front side of the switch lever 11, the switch lever 11 is returned to the rear lock-off position by the compression spring 18. When the switch lever 11 is returned to the lock-off position, the engagement arm 15c is located immediately below the lock arm 17, so that the switch lever 11 is returned to the lock-off state in which the pulling operation to the on-position side is prohibited.

In addition to the above lock-off function, the switch 10 of this embodiment has a lock-on function. As shown in FIG. 3, the switch body 11 is turned on by tilting the switch lever 11 to the ON position indicated by the white arrow C while the switch lever 11 is slid to the lock-off release position indicated by the white arrow A. Thus, the electric motor 5 can be started. After that, as shown in FIG. 4, the lock operation member 15 is tilted to the lock-on position side indicated by the white arrow B (the direction in which the front end portion 15b is displaced to the front side).
By this lock-on operation, the lock-on claw 15 d of the engagement arm portion 15 c enters above the lock claw 17 a of the lock arm 17. For this reason, if the grip of the switch lever 11 toward the on position side is weakened while holding the lock-on operation of the lock-on operation member 15, the lock-on claw 15 d is moved by the urging force of the compression spring 13 against the switch lever 11. The lock claw 17a is engaged so as to be pressed from above. Since the lock-on claw 15d of the engagement arm portion 15c is engaged with the lock claw 17a of the lock arm 17 from above, the lock operation member 15 is held at the lock-on position and the switch lever 11 is off-side. The tilt to is restricted.
Since the tilting of the switch lever 11 toward the off position is restricted and held in the on position, the switch body 12 is held in the on state, and thus the electric motor 5 is locked in the activated state. Since the switch lever 11 is locked in the ON position, the user can lock the electric motor 5 in the activated state without pulling the switch lever 11, and therefore, the user can grip the handle portion 4 and work easily. be able to.

When the user grips the switch lever 11 again from this lock-on state, the lock-on claw 15d of the lock operation member 15 is displaced upward and the engagement state of the lock arm 17 with the lock claw 17a is released. Therefore, the lock operating member 15 is returned to the direction (the counterclockwise direction in the drawing, the lock-on release position side) in which the tip end portion 15b is displaced rearward by the urging force of the torsion spring 16. As shown in FIG. 3, when the lock operating member 15 is returned to the lock-on release position, the switch lever 11 can be returned to the lower OFF position side. After the switch lever 11 is returned to the off position side and the switch body 12 is turned off, when the slide operation to the front side of the switch lever 11 is stopped, the switch lever 11 is moved to the rear lock-off position by the urging force of the compression spring 18. Returned to
As shown in FIG. 2, when the switch lever 11 is returned to the lock-off position on the rear side, the engagement arm portion 15c of the lock operation member 15 is again positioned directly below the lock arm 17, so that the switch 10 is The initial lock-off state is restored.
As described above, according to the switch 10 of the present embodiment, the switch lever 15 is released from the lock-off state by sliding the switch lever 15 in the lock-off release direction indicated by the white arrow A in FIG. be able to. Further, the switch lever 11 can be switched to the lock-on state by tilting the lock operation member 15 in the lock-on direction indicated by the white arrow B in FIG. 4 while the switch lever 11 is held in the on position. Since the member operated to release the lock-off mechanism (switch lever 11) and the member operated to activate the lock-on mechanism (lock operating member 15) are different members, the user can lock the lock-off mechanism. The off-release operation and the lock-on switching operation can be clearly distinguished and operated. Therefore, after the lock-off state is released, the switch 10 is not unintentionally switched to the lock-on state, and the switch 10 that clearly reflects the user's operation intention in this respect. Can do.

Various modifications can be made to the embodiment described above. For example, although the switch lever 11 is illustrated as an operation member for releasing the lock-off state of the switch 10, another operation member may be provided to release the lock-off state.
In addition, the configuration in which the switch lever 11 is slid to release the lock-off state is illustrated. However, in the case of using another operation member, the lock-off state may be released by a tilting operation instead of the sliding operation. .
Further, the lock-off state may be released by operating an operation member provided separately from the switch lever 11, and then the slide lever 11 may be switched to the lock-on state by, for example, a sliding operation to the front or rear side.
Further, although the disk grinder is exemplified as the electric tool, the switch according to the present invention can be widely applied as a switch of other electric tools such as an electric drill for drilling.

1 ... Electric tool (disc grinder)
DESCRIPTION OF SYMBOLS 2 ... Tool body part 4 ... Handle part 4a ... Handle case 5 ... Electric motor 8 ... Grinding stone 10 ... Switch 11 ... Switch lever 11a ... Window part, 11b ... Long groove hole, 11c ... Restriction arm part, 11d ... Engagement claw 12 ... Switch body, 12a ... Operating knob 13 ... Compression spring 14 ... Support shaft 15 ... Lock-on operation member 15a ... Support shaft portion, 15b ... Tip portion, 15c ... engaging arm portion, 15d ... Lock-on claw 17 ... Lock arm, 17a ... Lock claw, 17b ... Engaging protrusion 18 ... Compression spring 19 ... Switch base, 19a ... Window

Claims (2)

A switch lever that can be tilted up and down between an on position for starting the electric tool and an off position for stopping the electric tool and can be slid in the front-rear direction, a lock on position that locks the switch lever in the on position, and the lock on A switch having a lock-on operation member capable of moving between a lock-on release position for releasing the state ,
The lock-on operation member is provided on the switch lever so as to be movable.
In the initial position where the switch lever is slid rearward, the lock-on operation member located at the lock-on release position restricts the tilting operation of the switch lever toward the on-position side to enter the lock-off state. The off-state is released by sliding the switch lever forward, so that the switch lever can be tilted to the on-position side, and the lock-on operation member is moved in a state in which the switch lever is tilted to the on-position side. A switch configured to be in a lock-on state in which the switch lever is locked at the on position by moving to the lock on position . An electric tool comprising the switch according to claim 1.

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