JPH02215492A - Vibrating type electric razor - Google Patents

Abstract

PURPOSE:To simultaneously obtain the reduction of a load and the improvement of sharpness by providing a weight supported with an elastic leg and vibrating the weight with a cam provided to the driving shaft of a motor. CONSTITUTION:In the internal part of a grip part 11 side of a head part 12, an annular weight 4 supported with a pair of elastic legs 40 is arranged. For the motor 2 arranged in the upper part of the grip part 11, a cam 3 is attached to an output shaft projected into the head part 12, and the cam 3 is positioned in the opening of the central part of the weight 4. At present, when the cam 3 is rotated once by the motor 2, the cam 3 equipped with three tops reciprocates the weight 4 three times in the short shaft direction of the central opening, the vibration three-fold that of the rotating speed of the motor 2 is given to the weight 4, and the vibration of the weight supported with the elastic legs 40 is transmitted to the head part 12. The vibrating direction is made to coincide with the blade tip direction of a razor blade 16 attached to a fitting base 15.

Description

[Detailed description of the invention] [Industrial application field]

The present invention relates to a vibrating electric shaver that vibrates a head portion to which razor blades are attached.

[Conventional technology]

The most common means of shaving is a so-called safety razor, but in the case of people with thick beards, it is necessary to press it against the skin with great force to shave the beard, and it can sometimes irritate the skin. There is a risk of cutting it. Electric shavers are generally equipped with an outer cutter and an inner cutter that slides against the inner surface of the outer cutter.
There are also vibrating electric razors that have a vibrating head that has razor blades attached to them, similar to those used in safety razors. This type of electric shaver disclosed in Japanese Unexamined Patent Publication No. 63-220898 has an eccentric weight 6 attached to the output shaft of a motor 8, as shown in FIG. 17, and vibration is suppressed by rotating the eccentric weight 6. It was something that caused it to happen.

[Problem to be solved by the invention]

In this case, the inertial force F of the eccentric weight is the mass of the eccentric weight W
, when the eccentricity is e, the angular velocity is ω, and the gravitational acceleration is 2. F=W-e・ω"/g, and this inertial force F acts as a load on the output shaft of the motor. Inertial force is a factor that determines the amplitude of the head, and the In order to optimize the sharpness of the razor, the amplitude setting is performed by appropriately selecting the mass W and eccentricity e of the eccentric weight.In other words, the load is automatically determined by these. Therefore, if you try to reduce the above-mentioned load in a battery-powered product in order to extend the shaving time, this will have no choice but to reduce the frequency and amplitude, which will also reduce the sharpness. In addition, with the above structure, the frequency = the number of rotations of the motor, and considering the life of the motor and the power consumption of the motor,
It is difficult to obtain a rotation speed (vibration frequency) of 10,000 rpm or more, and 110,000 s is desired to improve sharpness.
Even if the amplitude is reduced by decreasing the value of W-e in the above formula in order to obtain a frequency higher than p, the load on the motor and the current consumption by the high-speed motor will increase, and the time available for shaving will be reduced. This will end up making it shorter. The present invention has been made in view of these points, and its purpose is to provide a vibrating electric shaver that can reduce the load and improve the sharpness at the same time.

[Means for Solving the Problems] Accordingly, the present invention provides a vibrating electric shaver that vibrates a head portion to which razor blades are attached, and provides a weight supported by elastic legs to drive the motor. Its unique feature is that it vibrates using a cam attached to the shaft. [Function] According to the present invention, vibration is generated by a cam rotationally driven by a motor vibrating a weight supported by an elastic leg, and it is possible to generate vibration regardless of eccentricity. Because of this, the inertial force is small, so the load can be reduced, and the vibration frequency can also be set to an integral multiple of the motor rotation speed depending on the shape of the cam. [Example] The present invention will be described in detail below based on the illustrated example.
Figures 3 to 3 show one embodiment. This vibrating electric shaver 1 includes a grip part 11 containing a motor 2 and a battery 5, a battery cover 13 attached to the lower end of the grip part 11, and a head part 1 connected to the upper end of the grip part 11.
2 and two razor blades 16.16.
Reference numeral 14 in Fig. 6 is a switch, which is formed by a cartridge-type mounting base 15 that is detachably attached to the upper end of the switch. An annular weight 4 supported by a pair of elastic legs 40, 40 is disposed inside the head section 12 on the grip section 11 side. Both elastic legs 40 have a fixing piece 41 at the lower end that is clamped and fixed between the head section 12 and the grip section 11.
．． 40 has a ring-shaped upper part, and the annular weight 4 is fixed to the inner surface of this ring-shaped part. The elastic legs 40, 40 formed into thin plate shapes are as follows:
The razor blade 16 mounted on the mount 15 is flexible in the direction of the cutting edge, but is difficult to bend in the direction perpendicular to this direction. The motor 2 disposed in the upper part of the grip part 11 has a cam 3 attached to an output shaft protruding into the head part 12, and this cam 3 is positioned within the opening in the center of the weight 4. are doing. Here, the central opening of the weight 4 has a rectangular planar shape, and the cam 3 has the shape shown in FIGS. 4 and 5.
As shown in the figure, the planar shape is a triangle (rice ball shape) in which the length of two line segments passing through the center of rotation is constant. Now, when the cam 3 rotates once by the motor 2, the cam 3, which has three tops, makes the weight 4 reciprocate three times in the direction of the short axis of its central opening.
twice as much vibration is applied to the weight 4, and the elastic leg 40.40
The vibration of this weight 4 supported by the head part 12
transmitted to. Note that the vibration direction is made to match the direction of the cutting edge of the razor blade 16 mounted on the mounting base 15. The rotation center of the cam 3 is not eccentric, so the inertial force in the cam 3 is zero, and the inertial force F' of the weight 4 is a simple harmonic motion in the direction of the cutting edge, so F'= (W-e・027g)・2/π Also, the inertia force F” of the elastic leg 40.40 is calculated as follows: F”=P・
2/π, and the value of F" can be reduced by reducing the spring constant of the elastic leg 40.40 or by reducing the amount of eccentricity e, so the inertia in the conventional example can be reduced. Compared to the force F, F>F'+F''', specifically, it can be reduced by about 2/π, and the load on the motor 2 can be reduced. Furthermore, even if the inertial force becomes smaller, the maximum centrifugal force in the vibration direction remains the same as before, so the amplitude does not decrease.As mentioned above, the vibration frequency is 3 times the rotational speed of the motor 2. Because of this, even if the amplitude is small, it is possible to secure sharpness with a high frequency, so even if the value of F is further reduced and the load is reduced, good sharpness can be obtained. becomes. Moreover, since the vibration direction is only a component in the direction of the cutting edge, it is possible to prevent skin cutting, which would be a problem when vibration occurs in a direction parallel to the cutting edge. The shape of the cam 3 may be an eccentric circular shape as shown in FIG. 6 or an eccentric elliptical shape as shown in FIG. 7. However, in this case, the cam 3 may be eccentric in the opposite direction. It is preferable to provide a balancer 30 such that the center of gravity coincides with the center of rotation of the motor 2.Also, even when using such an eccentric cam 3, as shown in FIG. If the cams 3 and 3' are provided, the vibration frequency can be made an integral multiple of the rotational speed of the motor 2. In the figure, 30' is a balancer corresponding to the cam 3'. In the above embodiment, the elastic legs 40 supporting the weight 4 are arranged by sandwiching the fixing piece 41 between the grip part 11 and the head part 12, but as shown in FIGS. 1
As shown in Figure 0, the fixing piece 41 is annular and the motor 2 is press-fitted into the fixing piece 41 so that the elastic legs 40 do not come into direct contact with the grip part 11 or the head part 12. 42 in the figure is the engagement with the motor 2, which can prevent the occurrence of a situation where the fixing condition of the fixing piece 41 of the elastic leg 40 changes due to an external load, resulting in an increase in load. This is a protrusion that prevents rotation. Further, as shown in FIG. 11, when the fixing piece 41 is held between the grip part 11 and the head part 12, by interposing a cushion material 43, it is possible to similarly prevent an increase in load due to the degree of gripping. Can be done. Furthermore, as shown in FIGS. 12 to 14, a slit or the like is formed in the fixed piece 41 of the elastic leg 40 to form an elastic portion 44 that is easily deflected in a direction orthogonal to the direction in which the elastic leg 40 is deflected. By doing so, the elastic leg 40 can be prevented from twisting due to the frictional resistance acting between the cam 3 and the weight 4 by the deflection of the elastic part 44. Strength can be ensured. As shown in Fig. 15, when the weight 4 made of metal is integrally molded with the elastic leg 40, 40 made of synthetic resin, the weight 4 is embedded in the synthetic resin so that the contact with the cam 3 has high wear resistance. The cam 3 is made of metal and is made of a molded product.
By preventing direct contact with the weight 4, noise can be suppressed, and by filling with grease or the like, wear resistance can be increased. As shown in FIG. 16, if the thickness of the cam 3 is made smaller than the thickness of the central opening of the weight 4, or if the outer peripheral surface of the cam 3 is made spherical, the output shaft of the motor 2 to which the cam 3 is attached Weight 4 supported by center line and elastic legs 40.40
Even if the parts are assembled so that their center lines intersect with each other, an increase in load due to twisting can be prevented.

【Effect of the invention】

As described above, in the present invention, vibration is generated by a cam rotationally driven by a motor vibrating a weight supported by an elastic leg, and it is possible to generate vibration regardless of eccentricity. Because of this, the inertia force is small, and therefore the load can be reduced.In addition, the vibration frequency can be set to an integral multiple of the motor rotation speed depending on the shape of the cam, resulting in good sharpness. It is possible to easily achieve the high vibration frequency required to obtain a sharp cutting edge, and it is possible to reduce the load and improve sharpness at the same time.

[Brief explanation of the drawing]

Fig. 1 is a perspective view of an embodiment of the present invention, Fig. 2 is a vertical sectional view of the same, Fig. 3 is a perspective view of the elastic legs and weight of the same, Fig. 4 is a horizontal sectional view of the same, and Fig. 5 is a perspective view of an embodiment of the invention. (a) and (b) are a plan view and a sectional view of the same cam as above, FIGS. 6(a) and (b) are a horizontal sectional view and a partial sectional view of another embodiment, and FIGS. 7(a) and (b) are A plan view and a sectional view of another cam, Fig. 8(a), (b), and (c) are a plan view, a sectional view, and a sectional view of another cam, and Fig. 9 is another example of the elastic leg fixing structure. 10 is a perspective view of the same elastic leg as above, FIG. 11 is a sectional view showing still another example of the fixing structure of the elastic leg, and FIG. 12 is a sectional view showing still another example of the elastic leg. , FIGS. 13(a) and 13(b) are a cross-sectional view taken along line AA and line B-B in FIG. 12, and FIG. 14 is a perspective view of the elastic leg shown above.
FIG. 15 is a sectional view of another example of an elastic leg and weight, FIG. 16 is a sectional view of another example of a cam, and FIG. 17 is a sectional view of a conventional example, in which 2 is a motor, 3 is a cam, 4 is the weight, 12 is the head part,

Claims (1)

[Claims] (1) A vibrating electric shaver that vibrates the head to which razor blades are attached is characterized by providing a weight supported by elastic legs and causing this weight to vibrate with a cam provided on the drive shaft of the motor. A vibrating electric razor.