JPS6014445Y2 - Rotary electric shaver inner blade support device - Google Patents

Description

[Detailed description of the invention] This invention is a rotary electric shaver that supports the inner blade so that it rotates so that the tips of the inner blades are always in contact with the outer blade at a constant angle, resulting in good sharpness. be.

Hereinafter, one embodiment of the present invention will be described based on the drawings.
Reference numeral 1 denotes a circular inner cutter base made of synthetic resin or the like, which is provided with slots 3, 3.3 so that three inner cutter pieces 2, 2.2 can be attached radially.

4, 4.4 is a plate-shaped spring attached to the back surface of the inner cutter stand 1, which is bent in an arc shape, and has a key hole 5 at the base end.
This hole 5 is fitted into a mounting boss of the same shape on the back side of the inner cutter base, and the boss is burned and fixed.

Conventionally, the inner blade piece 2 is attached to the plate spring 4 by simply providing a horizontally elongated attachment hole 6 at the lower end of the inner blade element 2, and inserting the free end of the plate spring 4 into the attachment hole 6. was inserted.

Therefore, since the plate spring 4 is loosely inserted into the mounting hole 6, the inner blade piece 2 is movable.

Next, the situation when the inner blade piece installed in the conventional method mentioned above slides against the outer blade to cut hair will be explained based on Fig. 1.
When there is no load, that is, when no whiskers are introduced and the inner cutter base 1 is simply rotating in the direction of the arrow, the inner cutter piece 2 is affected only by the sliding resistance with the outer cutter 7, and the dotted line As in its current state, it has fallen slightly backwards.

When the whiskers are introduced from the outer cutter hole, the shearing resistance of the whiskers is added, which causes the inner blade element 2 to further gradually tilt backwards, and following this, the lower end of the inner blade element 2 becomes plate-shaped. The body moves on the spring 4 and becomes a solid line state.

When cutting the beard in this way, the inner blade piece 2 cuts while moving from the dotted line state to the solid line state, so the beard is pulled and feels damaged, resulting in poor sharpness.

Also, as shown by the solid line, the inner cutter piece 2 comes into contact with the edge of the inner cutter base slot 3 at its two upper and lower ends C and D, respectively, and the frictional resistance causes the inner cutter piece 2 to move smoothly. Vertical movement is impaired.

As a result, if the spring force is weak, the cutting edge 2' of the inner blade piece 2
The blade does not come into contact with the back surface of the outer blade with appropriate pressure, creating a gap, and in this case too, the hairs escape, leading to a decrease in sharpness.

The present invention attempts to improve these drawbacks.

For this purpose, it is necessary to fix the inner blade piece 2 in a constant state so that it does not move around when cutting the beard.

Therefore, in the present invention, a protruding portion 8 is provided at the center of the lower end of the inner blade piece 2.
is provided, and two grooves 9, 9 are formed in a set in this portion 8 to form three projecting pieces 10°, 11, and 10.

Notches i12, 12 are formed in the lateral direction at the outer edges of the two outer elastic protrusions 10, 10.

On the other hand, at the tip of the plate spring 4, a horizontally elongated insertion hole 13 is formed, the length of which is equivalent to the width A between the inner edges of the notched grooves 12 and 12 shown in FIG.

The width B of the insertion hole 13 in the front-rear direction is slightly larger than the thickness of the inner blade piece 2.

Next, to explain how to attach this inner cutter piece 2, the protruding pieces 10, 10 parts that protrude downward of the inner cutter piece 2 after being inserted into the slot 3 of the inner cutter base 1 are 4. As shown in FIG. 4, bend each other inwardly and insert into the insertion hole 13 of the plate spring 4.

Then, as shown in FIG. 3, when the elastic protrusions 1G and 10 are restored, the cutout grooves 12 and 12 completely fit into the longitudinal edges 13' and 13' of the insertion hole 13, and are securely fixed. .

As a result, the inner blade piece 2 is fixed at a fixed point relative to the plate-shaped spring 4, and does not move on the spring 4 because it is not simply inserted through the spring 4 as in the conventional case.

With the support device of this invention, both before and after shearing the beard,
The cutting edge 2' maintains contact with the back surface of the outer blade at a constant angle, and cuts hairs at this constant angle without wobbling as in the conventional case, allowing sharp shearing.

Also, the area where the inner edge of the inner cutter base slot 3 and the inner cutter piece 2 rub against each other is at one point C' in the figure, and the other area D' where they used to rub against each other is eliminated. The vertical movement of the inner blade piece 2 is now very smooth, and compared to the past, the phenomenon that the cutting edge 2' of the inner blade piece 2 separates from the back surface of the outer blade 7 has almost disappeared, resulting in a decrease in sharpness. The phenomenon will drastically decrease.

As mentioned above, the inner blade support device in conventional rotary electric shavers simply inserts the tip of the inner blade push-up spring into the mounting hole provided at the lower end of the inner blade piece. ,
When shearing the beard, the inner blade tips tend to escape due to the shearing resistance and pull the beard as if cutting, resulting in poor sharpness and an inability to make sharp cuts.

However, in the present invention, the lower end of the inner blade element is fixed to the inner blade push-up spring.

That is, a pair of elastic protrusions are provided at the lower end of the inner blade element, and a notch groove is formed in the lateral direction on the outer edge of each of these pieces.On the other hand, the tip of the plate spring for pushing up the inner blade is provided with a pair of elastic protrusions at the lower end of the inner blade element. A hole is provided for the insertion of the inner blade piece, and when installing the protruding pieces of the inner blade piece are inserted into this hole in a state in which they are bent inwardly, and then bent in the opposite direction again to return to the original state. Each cutout groove fits into the inner edge of this insertion hole to ensure secure fixation.

Therefore, the inner blade pieces maintain a constant state before and after shearing, and the tips of the inner blades contact the back surface of the outer blade at a constant angle and with a constant contact pressure.
The sharpness is always kept good.

In addition, the number of points of contact between the inner blade piece and the inner edge of the inner cutter base slot to which it is attached has been reduced from two places in the past to one, reducing frictional resistance and allowing the inner blade piece to move up and down smoothly. Stable sliding rotation with the outer cutter can be obtained.

[Brief explanation of the drawing]

Figure 1 is a cross-sectional view of the main parts of the inner blade attached using the conventional method, showing the movement of the inner blade piece before and after shearing, and an enlarged partial view of the cutting edge B part. 3 is a side sectional view and a bottom view of the inner cutter base equipped with a piece, FIG. 3 is a diagram showing the pattern before and after the inner cutter piece according to the present invention is attached, and FIG. 4 is a state before attachment and a protruding piece when attached. An external view of the inner blade piece in a state where it is bent and an external view of the plate spring for pushing up the inner blade,
FIG. 5 is a diagram of an attached state of the inner blade piece according to the present invention and an enlarged partial view of the cutting edge during shearing. 1...Inner blade stand, 2...Inner blade piece, 4.
...Plate spring, 10, 10... Projection piece, 12, 12... Notch groove, 13...
Inner blade piece insertion hole, 13', 13'... Insertion hole edge.

Claims (1)

[Scope of utility model registration request] The lower end of the inner cutter pieces arranged radially on the inner cutter stand is pushed up and supported by a plate-shaped spring attached to the back surface of the inner cutter stand, in which a pair of protrusions are provided at the lower end of the inner cutter piece. A horizontal notch groove is formed on the outer edge of each of the protruding pieces, the inner blade piece insertion hole is provided at the free end of the plate spring, and the protruding piece is inserted into the insertion hole. In addition, an inner blade support device for a rotary electric shaver, wherein the notch groove is engaged with the edge of the insertion hole.