JPS5836382Y2 - Rotary electric razor outer blade - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to the outer blade of a rotary electric razor, and relates to the structure of the net blade used therein, particularly the bone portion that forms the beard introduction hole (hereinafter simply referred to as the hole). .

The purpose of the present invention is to improve the strength of the outer cutter itself.

Conventionally, the hole shapes of outer cutters include round holes, square holes, hexagonal holes,
Elongated holes and their variations have been used, and spiral, concentric, continuous single hole arrangements, and combinations of two or more types of holes have been used, but when considering the shaving effect, , a concentric pattern in which the holes are arranged concentrically is most advantageous and has the following advantages:

First of all, the outer blade of a rotary electric razor is generally a part of a spherical surface, that is, a dome shape, so if the holes are arranged concentrically, the holes can be arranged efficiently, and the The area covered by the holes, that is, the aperture ratio can be increased.

The high aperture ratio makes it easy to capture beards, making it possible to cut long beards, curly hair, and other beards that were previously difficult to capture.

Next, since it is a concentric pattern, the rotation center of the inner cutter and the center of the outer cutter pattern almost coincide, and the relationship between the inner cutter and the hole, or the constituent elements of the hole itself can be expressed as a function of the distance from the center of the outer cutter.

For example, in order to perform a rough shave at the periphery of a dome blade and a final shave at the center, long holes may be placed at the periphery and fine holes at the center, or the hole and inner blade may be placed for the same purpose. It is possible and easy to increase the scissoring angle of the beard from the center of the outer blade toward the outer periphery, and to select various components of the outer blade hole depending on the use and purpose of the razor.

Although the concentric pattern has various advantages as described above, it also has the following disadvantages.

As shown in FIG. 1, when the outer cutter is viewed in the circumferential direction, band portions with continuous holes 1 and band portions 2b with continuous bones are alternately adjacent to each other.

When an external force is applied to the dome-shaped outer cutter, the outer cutter bends in the circumferential direction due to the difference in rigidity between the portion where the holes are continuous and the portion where the bone is continuous.

When considering the strength in the circumferential direction, the continuous part of the hole is several orders of magnitude weaker than the continuous part of the bone.

Therefore, stress is concentrated on the bone 2a in the radial direction, and there is a drawback that the bone 2a is weak in this portion.

Also, as shown in Fig. 3, the inner cutter 3 cannot reach the outer cutter center 4, or the circumferential speed is slow, so it is impossible to cut the beard, and there are no holes or even if there are holes. Some have a width of Q that does not contain whiskers, and have round holes of 1 mm or less, long holes, or no holes at all.

In the area where the hole is located, near the center of the outer cutter, near the boundary with the outer cutter center 4, as well as near the border between the outer cutter periphery 5 and the outer edge 6 of the outer cutter where no hole is provided. ,
Ranges of materials with different rigidities are adjacent to each other.

Therefore, when an external force is applied to the outer cutter, since the deflection of both the boundary parts is different, stress concentrates on the boundary part, resulting in a disadvantage that this boundary part is weak.

The present invention eliminates the above two drawbacks and takes advantage of the advantages of the concentric pattern.

The following will explain based on examples.

In FIG. 1, the concentric pattern is such that continuous portions of the hole 1, which in this embodiment is diamond-shaped (other shapes are also acceptable), and continuous portions of the circumferential bone 2b are alternately band-shaped in the circumferential direction. Since the outer cutter is connected to the outer cutter, when an external force is applied to the outer cutter, the rigidity of the two sharply differs, resulting in stress concentration and an imbalance in strength.

Therefore, in order to improve this problem, it is sufficient to reinforce the bones in the weak direction, and as shown in FIG. It is better to make it thicker than .

If the value of A/B is set to 1.1 to 2, especially 1.1 to 1.6, the purpose of the present invention can be fully achieved without impairing the ability to capture whiskers.

Next, in FIG. 3, the boundary between the outer blade center part 4 and the outer blade shaving perforation 7 and the boundary between the outer blade perforation 7 and the outer edge 6 of the outer blade are weak Although this is a problem, this can be improved by gradually changing the bone width or hole size.

That is, as shown in FIG. 3, in the shaving perforation, on the outer blade center side, the outer blade center boundary zone 8 has a bone width that gradually increases toward the center 4.

Also, in the outer cutter peripheral portion 5, the bone width is gradually increased toward the outer cutter outer edge portion 6.

The range of thickening is the commonly used length of 0.5 to 1.
If the hole is 8 mm, the bone width will be changed within the range of 2 to 4 holes.

Moreover, the range is from 2 to 2 of the bone width at the intermediate part between the outer blade center part 4 and the outer blade peripheral part 5, which occupy the majority of the outer blade.
A change of up to 4 times satisfactorily serves the purpose of the present invention.

In this embodiment, the bone width was changed, but the hole size may also be made smaller; in other words, the area of the hole per unit area, that is, the opening ratio, may be gradually changed.

What is necessary is to gradually reduce the aperture ratio from the center of the outer blade toward the outer edge.

In addition to the part where the opening ratio changes rapidly, when looking at the entire outer blade, the opening ratio may be gradually changed by gradually changing the bone width.

The aperture ratio is the percentage of the area covered by holes,
There is also a correlation with bone area, and the size of bone area per unit area is closely related to mechanical flexural rigidity.

In other words, it represents the degree of displacement when external force is applied.

The purpose of reducing changes in the aperture ratio is to prevent this deflection stiffness from changing rapidly.If the aperture ratio changes continuously, the deflection when an external force is applied will also be continuous. There are no places where stress is concentrated, and it becomes evenly distributed.

Therefore, the outer blade is strong against external forces.

Moreover, the following advantages are also produced at the same time.

That is, if the outer cutter is manufactured by an electrochemical method such as electroforming, the thickness of the outer cutter is determined by the current density, which is replaced by the aperture ratio of the outer cutter.

In the outer cutter according to the present invention, the aperture ratio gradually decreases from the center toward the outer edge, so the current density also gradually increases.

Therefore, when looking at the thickness of the completed outer cutter, the thickness changes gradually in some parts, and there is no place where the thickness changes suddenly.

Therefore, from this, when an external force is applied to the outer blade,
As the deflection changes gradually and the stress concentration occurs every time, it can be said that it is a strong external force.

Moreover, since the thickness can be made almost uniform, the razor effect can be made constant.

In this example, the center of the outer cutter and the rotation center of the outer cutter were made to coincide.

Further, in FIG. 3, a plurality of radial bone portions 9 extending from the center to the peripheral portion are provided, and a large number of blocks exist, with each adjacent bone portion being defined as one block.

Further, in the radial bone portion 9, a step is created so that the bone portion in the circumferential direction is discontinuous, so that the strength of the bone portion between the blocks is improved.

In addition, the center position of the circumferential bone portion is as shown in Figure 3.
In addition to being present on the center portion 4 side of the outer cutter, it may be located anywhere, but in this case, it is desirable that the centers be provided in the same direction within the block.

Therefore, if the outer cutter according to the present invention is used, it is possible to obtain a razor that is sufficiently strong, has good grip on beards, and has a good cutting quality.

[Brief explanation of drawings]

FIG. 1 is a partially enlarged view of a conventional concentric pattern outer cutter, FIG. 2 is a partially enlarged view of a concentric pattern outer cutter according to the present invention, and FIG. 3 is a plan view of an embodiment of the present invention. 1... Shaving hole (hole), 2a...
・Radial bone, 2b...Circumferential bone, 3...
...Inner cutter, 4...Outer cutter center, 5...
・Outer blade peripheral area, 6... Outer blade outer edge area, 7...
... Outer blade perforation part, 8... Outer blade center boundary zone.

Claims (3)

[Scope of utility model registration request] (1) In an outer blade in which shaving holes are arranged concentrically, the width of the bone in the radial direction is wider than the bone width in the circumferential direction among the bones constituting the holes, and the boundary part on the center side of the outer blade in the shaving hole part The outside of the rotary electric razor is characterized in that the width of the bone gradually increases as it approaches the center of the outer blade, and as it goes away from the outer edge of the outer blade near the outer boundary of the shaving perforation. blade. (2) The outer blade of the rotary electric shaver according to claim 1, wherein the opening ratio of the shaving holes is gradually reduced as the bone width gradually increases. (3) A plurality of radial bone parts extending from the center to the peripheral part are provided, a block is defined between the adjacent radial bone parts, and the shaving holes in the block are arranged concentrically, and the radial bone parts are arranged concentrically. The outer blade of a rotary electric shaver according to claims 1 and 2, wherein a step is created so that the bone portion in the circumferential direction is discontinuous.