JPH0113868B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] This invention relates to an outer cutter for a rotary electric shaver.

[Prior art and its problems]

Generally, in this type of electric shaver, the circumferential speed of the cutting edge of the inner cutter during rotation is faster as it approaches the outer end, so the hair introduced into the hair introduction hole of the outer cutter that corresponds to the rotation trajectory on the outer end side is is easily ejected without being sheared by the inner cutter. Therefore, an outer cutter is required that can effectively maintain the captured shearing effect regardless of the circumferential speed of the cutting edge of the inner cutter.

For this reason, there are already a first group of curved ribs extending from the center of the outer cutter base toward the outer circumferential side and along a number of arcuate curves curving in the rotational direction of the inner cutter, and a number of arcuate curves curving in the opposite direction. A second curved rib group along a curved line intersects with the rib group, and hair introduction holes of similar shapes are formed in a large number of approximately rhombic partitioned areas formed by intersecting this rib group according to the area of each area. There is.

However, in the above configuration, the inner peripheral side of the outer cutter base has a larger number of curved ribs than the first curved rib group and the second curved rib group compared to the outer peripheral side.
Because the curved rib groups intersect closely, the aperture ratio on the inner peripheral side is smaller than the aperture ratio on the outer peripheral side, resulting in poor hair introduction.

By providing intersecting rib groups separately on the inner circumferential side and outer circumferential side of the outer cutter base, and setting the pitch of the intersecting rib group on the inner circumferential side to be coarser than that on the outer circumferential side, the inner circumferential It has been considered to try to avoid a decrease in the aperture ratio on the outer circumferential side, but in that case, the extending direction of the intersecting rib group on the inner circumferential side and the extending direction of the intersecting rib group on the outer circumferential side are Since they are no longer located on the same curved line, the boundary between the two intersecting rib groups is irregularly deformed due to the pushing force from the skin.
There is a possibility that it will not be able to handle strong pushing force.

[Means for solving problems]

This invention provides a first group of curved ribs extending from the center side of the outer cutter base body toward the outer peripheral edge side and along a number of arcuate curves that curve in the rotational direction of the inner cutter, and a number of arcuate curves that curve in the opposite direction. A cross rib group that intersects the second curved rib group along the outer blade base is provided on the outer peripheral side of the outer blade base, and the rib interval on the outermost circumference is equal to the outermost circumference of the first and second curved rib groups. A third curved rib group that is set larger than the rib spacing, extends from the center side toward the outer peripheral edge, and is curved in the rotation direction of the inner cutter, and a number of arcuate curves that curve in the opposite direction. A cross rib group formed by intersecting with a fourth curved rib group along a curve is formed on the inner peripheral side of the outer blade base, and the cross rib group on the outer peripheral side and the cross rib group on the inner peripheral side are formed. The above-mentioned drawbacks are solved by providing a separation zone consisting of a large number of slits at the boundary between the two.

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings.

FIGS. 1 and 2 show an example of a dome-shaped outer blade of a rotary electric shaver according to the present invention.
In the figure, reference numeral 1 denotes a circular outer cutter base made of a thin steel plate with a thickness of about 50 μm, and is formed by, for example, electroforming.

A large number of substantially diamond-shaped hair introduction holes 2 are formed in the outer peripheral portion 1a of the outer cutter base 1.

The hair introduction hole 2 is formed as follows. A first group of curved ribs along a large number of arcuate curves extending from the center P side of the base body 1 toward the outer peripheral edge Q side, for example, an involute curve that unfolds toward the rotation direction of the inner cutter 3 (direction of arrow a). 4 and the second curved rib group 5 along the involute curve that develops in the opposite direction to the rib group 6. Approximately diamond-shaped holes having similar shapes are formed according to the area, and these are used as the hair introduction holes 2.

Reference numeral 7 denotes a large number of substantially diamond-shaped hair introduction holes formed on the inner peripheral portion 1b side of the outer cutter base 1. This hair introduction hole 7 also has almost the same shape as the hair introduction hole 2 on the outer peripheral portion 1a side, extends from the center P side of the base body 1 toward the outer peripheral edge Q side, and expands in the rotation direction of the inner cutter 3. A large number of intersecting rib groups 10 are formed by intersecting the third curved rib group 8 along the involute curve developed in the opposite direction and the fourth curved rib group 9 along the involute curve developed in the opposite direction. This is obtained by forming approximately rhombus-shaped holes of similar shapes in the approximately rhombus-shaped divided regions Sb according to the area of each region Sb. The rib spacing tb on the inner peripheral portion 1b side is set larger than the rib spacing ta on the outer peripheral portion 1a side.

Reference numeral 11 denotes an annular separation zone provided between the intersecting rib group 6 on the outer circumferential portion 1a side and the intersecting rib group 10 on the inner circumferential portion 1b side, and is composed of a large number of slits 12.

In this embodiment, the longitudinal direction of each slit 12 is set along the radial direction of the inner cutter 3. 13 is an outer blade holder.

In the above configuration, the angle of the hair receiving corner m of the substantially diamond-shaped hair introduction hole 2 on the outer circumferential portion 1a side becomes smaller as it is located on the outer circumferential side. In other words, even if the peripheral speed of the outer end of the cutting edge of the inner cutter 3 is high, the hair can be reliably captured at a small angle, and therefore the hair will not be thrown out from the hair introduction hole 2.
effectively disconnected.

Furthermore, a group of intersecting ribs 6 and a group of intersecting ribs 10 are separately provided on the outer circumferential portion 1a side and the inner circumferential portion 1b side of the outer cutter base body 1, respectively, and the rib spacing tb of the intersecting rib group 10 on the inner circumferential portion 1b side is set at the outer circumference. Since the rib spacing ta on the side of the portion 1a is set larger than that on the side of the outer circumference 1a, the aperture ratio on the side of the inner circumference 1b is almost the same as that on the side of the outer circumference 1a.

In particular, the rib groups 6, 10 are divided into the outer circumferential portion 1a side and the inner circumferential portion 1b side of the outer cutter base 1, and the starting point and ending point of each intersecting rib group 6, 10 are continuous in the extending direction. Even if they do not match, both rib groups 6, 1
Since the slit separation zone 11 is provided between the
Even if the bending direction of both rib groups 6, 10 does not follow the pushing force from the skin at the boundary, irregular deformation at the boundary can be prevented by the separation band 11 of the slit. Moreover, in this embodiment, since the slit is oriented in the direction along the inner cutter 3, the outer cutter base 1 is easily deformed from the center P to follow the rotation of the inner cutter 3 due to the pushing force. Therefore, the occurrence of cracks along the rib groups 6, 10 is suppressed.

[Effects of the Invention] As described above, according to the present invention, the blades extend along a number of arcuate curves that extend from the center P side of the outer cutter base body 1 toward the outer peripheral edge Q side and curve in the rotation direction of the inner cutter 3. A cross rib group 6 that intersects the first curved rib group 4 and the second curved rib group 5 along a large number of arcuate curves curving in the opposite direction is attached to the outer peripheral portion 1 of the outer cutter base 1.
a side, and the outermost rib interval tb is set larger than the outermost rib interval ta of the first and second curved rib groups 4 and 5, and from the center P side to the outer peripheral edge Q side. The intersection of the third curved rib group 8 along a large number of arcuate curves extending toward the rotational direction of the inner cutter 3 and the fourth curved rib group 9 along a large number of arcuate curves curving in the opposite direction. A group of intersecting ribs 10 are formed on the inner circumferential portion 1b side of the outer cutter base 1, so that the intersecting rib group 6 on the outer circumferential portion 1a side and the inner circumferential portion 1
Since the separation zone 11 consisting of a large number of slits 12 is provided at the boundary with the cross rib group 10 on the b side, the aperture ratio on the inner peripheral side of the outer blade base is prevented from decreasing, and
It is possible to provide an outer blade for a rotary electric shaver that can suppress abnormal deformation when receiving pushing force from the skin.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing an outer cutter of a rotary electric shaver according to the present invention, and FIG. 2 is a plan view of the outer cutter. DESCRIPTION OF SYMBOLS 1...Outer blade base, 1a...Outer circumference, 1b...Inner circumference, 4...First curved rib group, 5...Second curved rib group, 6...Cross rib group, 8... Third curved rib group, 9...Fourth curved rib group, 10...Cross rib group, 11... Separation zone consisting of slits, 12
...Slit, ta, tb...Rib spacing, P...Center, Q...Outer periphery.

Claims (1)

[Claims] 1 The first curved rib group 4 extends from the center P side of the outer cutter base body 1 toward the outer peripheral edge Q side, and curves in the opposite direction to the first curved rib group 4 along a large number of arcuate curves that curve in the rotation direction of the inner cutter 3. A cross rib group 6 that intersects a second curved rib group 5 along an arcuate curve is provided on the outer peripheral portion 1a side of the outer cutter base 1, and the outermost rib interval tb is set to the first and second curved rib groups 5. is set larger than the rib spacing ta on the outermost periphery of the curved rib groups 4 and 5, and extends from the center P side to the outer peripheral edge Q side,
A group of intersecting ribs formed by intersecting a third group of curved ribs 8 along a number of arcuate curves curving in the rotational direction of the inner cutter 3 and a fourth group of curved ribs 9 along a number of arcuate curves curving in the opposite direction. 10 is formed on the inner circumferential portion 1b side of the outer cutter base 1, and a number of slits 12 are formed at the boundary between the intersecting rib group 6 on the outer circumferential portion 1a side and the intersecting rib group 10 on the inner circumferential portion 1b side. An outer blade of a rotary electric shaver characterized by being provided with a band 11.