JPS5857163B2 - electric toothbrush - Google Patents

Description

[Detailed description of the invention] This invention relates to an electric toothbrush.

Conventional electric toothbrushes had short lifespans because no consideration was taken to absorb overload when it is applied to the output shaft that rotates the toothbrush back and forth.

Therefore, it is an object of this invention to provide an electric toothbrush with a long life.

A front view and an enlarged sectional view of essential parts of an embodiment of the electric toothbrush of the present invention are shown in FIGS. 1 and 2, respectively.

In these figures, 1 is the housing and 2 is the lower cover.
3 is a switch lever and 4 is a toothbrush.

The inside of the housing 1 is divided into two parts, with the upper side serving as a 1-drive section unit accommodating part 5 and the lower side serving as a battery accommodating part 6.

The drive unit housing section 5 includes a motor 7, a gear 8 press-fitted onto the output shaft of the motor 7, a reduction gear 10 having an eccentric pin 9 and loosely engaging with the shaft 10a, a drive lever 11 engaging with the eccentric pin 9, An output shaft 12 that is fitted into the drive lever 11 and rotated back and forth, a bearing 13, a waterproof gasket 14, an upper motor mount 15, a lower motor mount 16, an anode plate 17 that connects the motor 7 and the battery, A drive unit 19 consisting of a switch blade 18 is accommodated.

This drive unit 19 is fixed by a fixed spring body 21 having a fixed piece 20.

As shown in FIGS. 3 and 4, the drive lever 11 has a long groove 11a in a direction perpendicular to the output shaft 12 (FIG. 2).
The eccentric pin 9 engages with this long groove 11a and moves from side to side within the long groove 11a due to the rotation of the reduction gear 10.
In order to press the groove wall of a, the drive lever 11 is connected to the output shaft 12
The output shaft 12 swings around the center, thereby causing the output shaft 12 to reciprocate.

As shown in the figure, the lower motor mount 16 is adapted to be engaged with the upper motor mount 15 in an uneven manner.

A battery 6 a is housed in the battery housing section 6 , and its lower end is supported by the lower cover 2 .

The switch lever 26 consists of a switch lever 3, a copper ball 22, a spring 23, a switch cam 24, and an O-ring 25.
1 is attached to the upper part of the drive section unit accommodating section 5.

When the switch lever 3 is moved to the ON side along the circumference of the housing 1, the switch cam 30 presses the switch spring 18 and energizes the motor 7, so that the motor 7 rotates.

What should be noted is that when an overload is applied to the output shaft 12 as shown in FIG. It moves in the direction of the arrow.

With this configuration, when an overload is applied to the output shaft 12, the output shaft 12 moves in the direction of the arrow, and the distance a between the shaft 10a of the reduction gear 10 having the eccentric pin 9 and the output shaft 12 increases.

Therefore, the eccentric pin 9 comes to engage with the outside of the long groove 11a of the drive lever 11, and the swing angle of the drive lever 11 becomes smaller, and the rotation width of the reciprocating rotation of the output shaft 12 becomes smaller.

As a result, no overload is applied to the motor 7, resulting in a long life.

FIG. 5 is a rear view of a main part of an embodiment of the present invention, that is, a drive lever, and FIG. 6 is a sectional view thereof.

In this actual case, the outer portion of the long groove 31a of the drive lever 30, that is, the groove width 31a on the side opposite to the output shaft 12 is widened to increase the play of the eccentric pin 9.

The other parts are the same as the actual case described above.

As a result of doing this, when an overload is applied, the output shaft 1
In addition to the movement of 2, the play of the eccentric pin 9 increases,
The rotation width of the output shaft 12 becomes even smaller.

As described above, the electric toothbrush of the present invention is provided with a movable output shaft for attaching the toothbrush to the housing,
A drive lever with a long groove is fitted to this output shaft so that the long groove is perpendicular to the output shaft, and an eccentric pin is provided on the gear rotated by the motor and engaged with the long groove to rotate the drive lever back and forth. Since the output shaft moves away from the eccentric pin when an overload is applied to the output shaft, no overload is applied to the motor.

Therefore, electric toothbrushes have a longer lifespan.

[Brief explanation of the drawing]

Fig. 1 is a front view of one embodiment of the present invention, Fig. 2 is an enlarged sectional view of the main part thereof, Fig. 3 is a rear view of the 7 drive lever, Fig. 4 is a sectional view thereof, and Fig. 5 is an enlarged sectional view of the main part thereof. The rear view of the embodiment and FIG. 6 are its sectional views. 1...Housing, 4...Toothbrush,
7...Motor, 9...Eccentric pin, 10
...Reduction gear, 11... Drive lever
12... Output shaft, 15... Upper motor mounting base, 16... Lower morph mounting base, 27...
...Support protrusion, 28...Plate.

Claims (1)

[Claims] 1. A movable output shaft for attaching a toothbrush to the housing is provided, and a drive lever with a long groove is fitted to the output shaft so that the long groove is perpendicular to the output shaft. An electric toothbrush in which a pin is provided and engaged with a long groove to rotate the drive lever back and forth, so that when an overload is applied to the output shaft, the output shaft moves away from the eccentric pin.