JPH0790521B2 - Electric knife equipment - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric cutting tool device for cutting an object to be cut by rotationally driving the cutting blade.
The present invention relates to an electric cutting tool device equipped with means for turning off a power switch and means for locking rotation of a blade.

[0002]

2. Description of the Related Art Electric cutting equipment cuts wood, metal, etc. like a circular saw, and cuts grass and weeds like a lawn mower. It is extremely dangerous to touch it, etc., and it may be scratched if you touch other things, so be careful when handling it.

Particularly in a rechargeable electric blade device, since the power cord is not provided in the main body, it is easy to carry and operate, while the battery is still attached to the main body.
It is often carried, stored in a carrying case, or the blade is replaced, and if the power switch is inadvertently turned on, the danger to the human body is considerably high. For this reason, there is one equipped with an off-lock lever so that the power switch is not turned on carelessly.
Normally, the off-lock lever cannot be pulled in by inserting an inclusion (a part of the off-lock lever) between the trigger lever of the power switch and the switch body that slidably supports the trigger lever. I am trying. This inclusion is always biased by a spring toward the trigger lever, and normally there is an inclusion between the switch body and the trigger lever.
In that condition, the trigger lever cannot be retracted. In the case of use, first, it is necessary to slide (move) the off-lock lever and then retract the trigger lever of the power switch. Therefore, even if an object or a finger accidentally touches the trigger lever, it does not move.

However, in such a conventional example, the power switch is off-locked, but the rotation of the blade is not stopped when the blade is replaced. In other words, the shaft to which the blade is attached is connected to the motor via the reduction block, the blade is sandwiched between the fixing flange and the tightening flange of this shaft, and the tightening screw is screwed into the shaft through the tightening flange to fix it. The structure makes it difficult to loosen and tighten the tightening screw when the shaft rotates. In particular, when tightening and tightening the screw to attach the blade, the deceleration block and the motor run idle at the same time without tightening until the end, and there is a problem that the blade cannot be firmly fixed as it is. Therefore, those disclosed in Japanese Utility Model Publication No. 59-5302 and Japanese Utility Model Publication No. 59-87910 have been proposed. 59-
As disclosed in Japanese Patent Publication No. 5302, a flat portion d is provided on a collar c of a shaft b for fixing a circular saw blade a as shown in FIG. 7, and a shaft stopper e which can be fitted in the flat portion d is movable back and forth. f
The shaft stopper e is urged by a spring g so as to separate from the flat surface portion. When replacing the blade, the shaft stopper e is slid against the spring g to fit the shaft stopper e into the flat surface portion d of the collar c and hold the shaft b so as not to rotate. ing. 59-87
The lock pin disclosed in Japanese Patent No. 910 has a gear h integrally provided on a shaft b for fixing a circular saw blade a, an engaging hole i provided therein, and a gear case j slidably mounted as shown in FIG. k
The distal end of the lock pin is freely engaged with and disengaged from the engagement hole i, and the lock pin k is biased by the spring m so as to be disengaged from the engagement hole i.
An auxiliary switch n is arranged near the lock pin k, and the auxiliary switch n and the power switch are connected in series. If the lock pin k is pushed against the spring m when replacing the blade, the lock pin k will be engaged with the engaging hole i.
The shaft b can be held so as not to rotate by engaging with, and at this time, the auxiliary switch n is turned off so that the power is not turned on.

[0005]

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention
In the case of Japanese Patent No. 5302, there is a possibility that the power switch is inadvertently turned on when the shaft is rotationally locked so that the shaft does not rotate, which is dangerous and of course the motor is overloaded and locked. The motor may be burned or the mechanical part may be damaged. In addition, actual development Sho 59-87910
Since the auxiliary switch is connected in series to the main circuit in the publication of the publication, there is a problem that electrical loss occurs, and when carrying it, accidentally turning on the power switch causes injury or contact Problems such as non-function when welded cannot be solved.

SUMMARY OF THE INVENTION The present invention is intended to solve the above-mentioned problems, and is intended to provide an electric bladed tool in which the blade can be easily replaced and is safe, and damage to the apparatus can be prevented. is there.

[0007]

In order to achieve the above object, the electric cutting tool of the present invention mechanically locks a locking means for locking the rotation of the rotary shaft so that the blade 7 does not rotate and a power switch 3 at an off position. in the electric tool device having an off-lock unit configured to, the power switch 3 on and off operation
Block the movement of the trigger lever 3b to the ON position.
The off lock lever 8 having the stopper 8c
And a pinio which is provided on the motor shaft 14a.
A tooth portion that meshes with the motor 15 and prevents rotation of the motor shaft 14a.
Locking means is constituted by the lock lever 10 having 10b
If the motor shaft 14a is locked by the locking means,
Of the trigger lever 3b.
The lock lever 10 is installed so that it cannot be released in the locked state.
The protrusion 13 and the off-lock lever 8 provided
It is characterized in that the locking means and the off-lock means are interlocked with each other at the projection portion 28 .

[0008]

According to the above construction, when the power switch 3 is off-locked by the off-lock means, the power switch 3 is kept in the off state, and there is no possibility that the power is inadvertently turned on. When the rotary shaft is locked by the locking means, the blade 7 does not rotate, and the blade 7 can be easily replaced. Further, when the blade 7 is locked so as not to rotate, the power switch 3 is always off-locked and the power switch 3 is never turned on.

[0009]

EXAMPLES The present invention will be described in detail below with reference to examples of circular saws.
As shown in FIGS. 1 to 4, a motor 14 and a gear box 9 are arranged in a housing 1 in which a handle portion of a circular saw body is formed, and a motor 14 is turned on and off in a central portion. There is a power switch 3, a contact fitting 2a is projected from the rear end of the power switch 3 toward the battery pack 2, and the contact fitting 2a is connected to the battery pack 2. The motor 14 is fixed to the gear box 9,
As shown in FIG. 4, a pinion 15 meshing with a gear 18 is fixed to the motor shaft 14a. The gear 18 and the gear 19 are fixed to a shaft 17 rotatably supported by a bearing 16, and the gear 19 is arranged so as to mesh with a gear 22 press-fitted and fixed to an output shaft 23. Bearing 20
Also, a fixed flange 23b is integrally provided at one end of the output shaft 23 rotatably supported by the bearing 21, and a blade 7 such as a saw blade is provided on the blade mounting protrusion 23a of the fixed flange 23b.
Is positioned and the tightening screw 25 is screwed into the screw hole 23c through the tightening flange 24 to fix the blade 7. The gear box 9 is fixed to the housing 1 of the circular saw body, and a lower guard 6 is rotatably supported at one end of the gear box 9, and a retaining ring prevents the gear box 9 from coming off. This lower guard 6 is located outside the housing 1 of the circular saw body, and a safety cover 5 is fixed to the outer periphery of the housing 1 so as to surround the lower guard 6 and the blade 7. Further, the circular saw body is supported by the base 4, and the lower guard 6 portion extends below the base 4 through a through hole formed in the base 4.

At the center of the circular saw body, an off-lock lever 8 of off-lock means is rotatably supported by a shaft 8a protruding from the housing 1, and the off-lock lever 8 is operated.
The portion 8b is exposed to the outside of the housing 1. A stopper 8c is provided in the center of the off-lock lever 8 so as to project toward the power switch 3 side, and the stopper 8c is inserted in a gap 3c between the switch body 3a of the power switch 3 and the trigger lever 3b. It is like this.
A spring shaft 8d is formed on the off-lock lever 8 so as to project in a direction opposite to the stopper 8c. The spring shaft 8d has an arc shape centered on the shaft 8a. The spring shaft 8d is slidably inserted into a slit provided in the rib 8e of the housing 1, and the coil spring 12 is inserted into the spring shaft 8d, and the coil spring 12 is inserted into the rib 8e of the housing 1 and the off-lock lever 8. And the off-lock lever 8 is urged toward the power switch 3 side. A lock lever 10 as a locking means is arranged between the off-lock lever 8 and the gear box 9, and the lock lever 1 is attached to a shaft 10 a protruding from the housing 1.
0 is rotatably supported. This lock lever 10
Is provided with a tooth portion 10b that meshes with the pinion 15.
A tension spring 10e is provided between the boss 10c provided on the lock lever 10 and the boss 10d provided on the housing 1.
The pulling spring 10e urges the lock lever 10 to rotate toward the pinion 15 side so that the tooth portion 10b engages with the pinion 15. Further, the lock lever 10 is provided with a rotary protrusion 11 having a smooth curved surface, and the rotary protrusion 11 faces a stop rib 30 provided on the gear box 9. The housing 1 is provided with a hole 1a communicating with the outside so as to correspond to this portion, and a piece of the hexagon wrench 26 can be inserted into the hole 1a. Hex wrench 26 between 11 and stop rib 30
It is designed to be sandwiched between. Further, the off-lock lever 8 and the lock lever 10 are provided with projecting portions 13 and 28 which come into contact with each other in a predetermined positional relationship. A cover 27 that opens and closes the hole 1a by sliding is attached to a portion of the housing 1 to which the hexagon wrench 26 is attached. The cover 27 has ribs 2 protruding into the housing 1.
7a is provided.

Next, the operation of the off-lock lever 8 which is the off-lock means will be described. FIG. 6 shows a state in which the off-lock lever 8 is not operated. The off-lock lever 8 is rotated toward the power switch 3 by the bias of the coil spring 12.
Therefore, the stopper 8c of the off-lock lever 8 is inserted into the gap 3c of the power switch 3, the trigger lever 3a cannot move, and the power switch 3 is carelessly moved.
The motor 14 will not rotate due to. Here, as shown in FIG. 1, when the off-lock lever 8 is tilted toward the arrow A side, the stopper 8c comes out of the gap 3c and does not exist between the trigger lever 3b and the switch body 3a. Therefore, the trigger lever 3b is pushed to turn on the power switch 3. Can be turned on. Further, when the trigger lever 3b is pushed in, the off-lock lever 8 remains tilted to the arrow A side even if the trigger lever 3b is not operated. The lever 8 rotates to lock the power switch 3 off as described above.

Next, the operation of the lock lever 10 as the lock means will be described. FIG. 6 shows a state in which the blade 7 is locked so as not to rotate. At this time, the lock lever 10 acts on the tooth portion 10b and the pinion 1 by the action of the tension spring 10e.
5, the motor shaft 14a does not rotate and the output shaft 23 does not rotate.
The blade 7 is replaced in this state, and the tightening screw 25 is operated with the hexagonal wrench 26 to tighten or loosen it. Since the output shaft 23 does not idle when the tightening screw 25 is operated, the operation is easy and the screw can be securely tightened when tightened. Further, in this state, the protrusion 13 provided on the lock lever 10 is in a positional relationship of engaging with the protrusion 28 of the off-lock lever,
The off-lock lever 8 does not rotate even if the off-lock lever 8 is pressed toward the arrow A side in an attempt to rotate the shaft 8 a, and the stopper 8 c of the off-lock lever 8 includes the switch body 3 a of the power switch 3 and the trigger lever 3 b. Gap 3 between
The power switch 3 cannot be turned on because it is interposed in c. That is, when the output shaft 23 or the like is locked so as not to rotate, even if the trigger lever 3b of the power switch 3 is accidentally touched, the power switch 3 remains in the off state, so that troubles such as burnout of the motor 14 are prevented. be able to. Next, when the cover 27 is moved to the arrow B side in FIG. 6 and one piece of the hexagon wrench 26 is inserted in the direction of the arrow C from the hole 1a provided in the housing 1, the smooth curved surface portion of the rotation protrusion 11 of the lock lever 10 is inserted. Abut. Furthermore, the hexagon wrench 2 is resisted against the biasing force of the tension spring 10e.
When 6 is pushed in, the lock lever 10
Rotates about the shaft 10a, and the engagement between the tooth portion 10b and the pinion 15 is released. At the same time, the protrusion 13 of the lock lever 10 does not move to prevent the protrusion 28 on the off-lock lever 8 from moving. That is, when the hexagon wrench 26 is attached to the housing 1, the rotation lock of the output shaft 23 and the like is released and the power switch 3 can be operated. Next, when the off-lock lever 8 is operated in the direction of arrow A in FIG.
When the off-lock lever 8 is tilted, the cover 27 is pushed by the spring shaft 8d and moves in the direction opposite to the arrow B to close the cover 27. By the operation of closing the cover 27, the hexagon wrench 26 is prevented from being unintentionally removed, and at the same time, the hole 1a is closed to prevent chips generated during the work from entering the housing 1. Further, when the off-lock lever 8 is tilted and the power switch 3 is turned on, the hexagon wrench 26
Cannot be removed, and the motor 1
The problem of locking the rotation of 4 can be solved.

[0013]

Since the present invention is configured as described above, when the power switch is off-locked by the off-lock means, there is a risk that the power switch is kept in the off state and the power is turned on carelessly. The blade does not rotate when the rotary shaft is locked by the locking means and the blade can be easily replaced, but the power switch is always off-locked when the blade is locked so that it does not rotate. There is no need to drive the motor in a locked state so that the blade does not rotate, and it is possible to prevent burnout of the motor and damage to the mechanical part,
In addition, the number of parts can be reduced and electrical loss does not occur compared to using an auxiliary switch as in the past, and the power switch does not turn on when locked so that the blade does not rotate. Since it is mechanically locked, it is more safe than conventional auxiliary switches. In addition, the power switch on / off
A stopper that prevents the gar lever from moving to the ON position
Rotate off-lock means consisting of off-lock lever
Auxiliary switch can be
The shaft will not rotate when the blade is replaced
Power switch turns on carelessly when locked
The danger can be prevented without

[Brief description of drawings]

FIG. 1 shows an embodiment of the present invention and is a partially omitted cross-sectional view of a lock release state.

FIG. 2 is a side view of FIG.

FIG. 3 is a front view of FIG.

FIG. 4 is a cross-sectional view showing the speed reduction unit of the above.

FIG. 5 is a cross-sectional view showing a mounted state of the above blade.

FIG. 6 is a partially omitted cross-sectional view of the locked state of FIG.

FIG. 7 is a view showing a conventional example, in which (a) is a front view,
(B) is a sectional view.

FIG. 8 is a cross-sectional view showing another conventional example.

[Explanation of symbols]

 3 Power switch 7 Blade 8 Off lock lever 10 Lock lever

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Hideo Hatta 1048 Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Works Co., Ltd. (56) References: 59-87910 (JP, U) (JP, U)

Claims (1)

[Claims] 1. An electric cutting tool having lock means for locking the rotation of a rotary shaft so that the blade does not rotate and off-lock means for mechanically locking the power switch at an off position, and turning on / off the power switch. Trigger lever
With a stopper that prevents the
The flock lever constitutes the off-lock means, and the motor shaft
Prevents rotation of the motor shaft by meshing with a pinion provided on the
Locking device is composed of a lock lever with a tooth
However, when the motor shaft is locked by the locking means, the
Disengage the flock lever with the trigger lever in the off-locked state.
With the protrusion provided on the lock lever so that it cannot be removed
An electric bladed device, characterized in that the locking means and the off-lock means are interlocked with each other by a protrusion provided on the off-lock lever .