JPH0115596B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method of manufacturing an outer cutter for a reciprocating electric shaver.

[Conventional technology]

As is well known, the outer blade of a reciprocating electric shaver has a thin, flexible outer blade base with a large number of hair introduction holes remaining around it for reinforcement. It is generally formed using the wearing method.

Looking at the structure of the outer blade from the viewpoint of electrical resistance during electrodeposition, there are a hole region with a relatively high resistance value, a peripheral margin region with a relatively low resistance value, and furthermore, a hole region and a peripheral margin region. It can be divided into three boundary areas.

In the electrodeposition method, since the amount of electrodeposition per unit area is approximately constant, electrodeposition is performed to the same thickness in the hole region and the peripheral margin region. In this case, the hole region has a small area to be electrodeposited, whereas the peripheral margin region has a large area because it is often solid. Therefore, when electrodeposited for the same amount of time, the hole area is thicker and
It tends to be thinner in the peripheral areas. On the other hand,
Even in the above boundary region where high and low resistance values are mixed, the amount of electrodeposition per hour is the same as in other regions, but electrodeposited metal ions, such as nickel ions, have a low resistance value. It adheres more to people. In other words, in this boundary area, the ribs are pulled and adhered more toward the peripheral margin area, so that the rib thickness on the hole area side becomes thinner. In other words, between the central part of the hole region and the peripheral margin region, the hole region with a smaller electrodeposition area is thicker, but in the boundary region, the hole region with a higher resistance value is closer to the peripheral margin region with a small low resistance value. This results in a change in thickness within a single flat plate, such that it becomes thicker in some areas.

[Problem that the invention seeks to solve]

For this reason, it is proposed to reduce the diameter of the hair introduction holes existing in the boundary area and conversely widen the rib width to reduce the resistance value, thereby increasing the rib thickness and increasing mechanical strength. However, with such means for changing the hole diameter, when the outer cutter is curved and stretched, there are parts that are difficult to bend and parts that are easy to bend, resulting in poor contact with the inner cutter.

Moreover, when laying out the hair introduction holes, the shape, position, and aperture ratio of the hair introduction holes must be considered depending on each region, which results in a low degree of design freedom.

[Means for solving problems]

Therefore, the present invention provides the above-mentioned methods for forming a flexible rectangular outer blade base with a flat surrounding area surrounding a hole area where a large number of hair introduction holes are present, by an electrodeposition method. An electrically insulating thin film is formed on the main surface of the electrodeposited matrix corresponding to the hair introduction holes, and an isolated notch is formed in the electrically insulating thin film on one or all surfaces of the matrix. , the ratio of the surface area of the notch to the surface area of the thin film is,
The above-mentioned drawbacks are solved by making the portions closer to the center of the base body larger, and then performing electrodeposition on the main surface of the matrix.

〔Example〕

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

FIG. 1 shows the outer blade of a reciprocating electric shaver obtained by the manufacturing method of the present invention. In the figure, 1 is a flexible thin-walled outer blade base, which is formed by an electrodeposition method. It is something. Reference numeral 2 denotes a large number of hair introduction holes formed in the outer blade base 1 and having a planar shape such as a rectangle, square, or hexagon.
Assuming that the rectangular area in which the hole area S 1 exists is defined as the hole area S ₁ , the surrounding area is a reinforcement room S ₂ that surrounds the hole area S ₁ , and there is a boundary area between the two areas S ₁ and S ₂ .
S ₃ is present. Reference numerals 3 and 3 denote reinforcing plates made of synthetic resin or thin steel plate formed along both side edges of the outer cutter base 1, and 5 is a mounting piece for attaching to an outer cutter holder (not shown).

Next, the method for manufacturing the above-mentioned outer cutter will be explained step by step.

First, as shown in FIG.
A partially electrically insulating thin film 22 is formed on the main surface of the bristle insulating film 22 corresponding to the hair introduction hole 2, and each of these thin films 22 has an isolated notch 23 (boundary area S _{3 )} as shown in FIG. 23 ₁ . . . 23 _o ) are formed from the sides toward the central portion Sa, and the main surface of the mother die 21 is partially exposed. The ratio of the surface area of the notch 23 to the surface area of the electrically insulating thin film 22 is set to be larger (23 ₁ <23 _o ) as the portion approaches the center Sa side.

In this embodiment, all electrically insulating thin films 22
Although the notches 23 are formed so that the areas closer to the central portion Sa are larger, the notches 23 may be selectively provided in the electrically insulating thin film 22. The thin film 22 is formed by a well-known method, that is, by uniformly applying a photosensitive resin that is hardened by light, becomes insoluble, and has chemical resistance on the main surface of the matrix, and then a positive printing plate is tightly attached thereon. Then, each process of printing and development is performed. In addition to this method, a method of forming an oxide film on the surface of an aluminum matrix may also be used.

The matrix 21 on which the thin film 22 has been formed is immersed in an electrodeposition layer (not shown) to perform primary electrodeposition, and the primary electrodeposition is performed on the conductive surface of the matrix 21 to a thickness exceeding the thickness of the thin film 22. Form layer 24 (FIG. 4).

Through this primary electrodeposition, the cutout portions 23 ₁ ...2
An unnecessary electrodeposited layer 25 ₁ ...25 _o that does not become a product is also formed at the part _3o as a so-called waste electrodeposition part exceeding the thickness of the thin film 22, and in this state, the notch 23
The peripheral edge of the plate is also held down by electrodeposition to prevent it from turning up and lifting up, and to prevent it from shifting due to external force or other processing liquids in the next process.

Next, the matrix 21 is immersed in an aqueous solution of potassium dichromate or the like to perform a peeling treatment, and then a second electrodeposition is performed to form a second electrodeposition on the first electrodeposition layer 24. Form layer 26. Through this secondary electrodeposition, the electrodeposition layer 25 as the above-mentioned sacrificial electrodeposition portion
₁ ... _25o. Unnecessary electrodeposited layers 271... _27o are also formed on the electrodeposited layers ₂₇₁ ...27o.

After the second electrodeposition, if the matrix 21 is pulled up from the electrodeposition layer and the second electrodeposition layer 26 is peeled off from the peeling surface, the second electrodeposition layer 26 will be removed as shown in FIG. An outer cutter is obtained which constitutes the outer cutter base 1 between the hair introduction holes. The above unnecessary electrodeposition layers 25 ₁ ... 25 _o and 27
₁ ...27 _o are isolated at the portions corresponding to the hair introduction holes 2, and are therefore left on the matrix 21 side.

Here, since the above-mentioned notch 23 is formed to have a larger area toward the center Sa side (23 ₁ <
_23o ), electrodeposition in which almost the same amount of deposits per unit area is performed is that in areas where notches ₂₃₁ ... _23o are provided, the ribs between the hair introduction holes are deposited in the amount deposited on these notches ₂₃₁ ... _23o . The amount of electrodeposition on the rib portion decreases, and the amount of electrodeposition on the rib portion increases from the center Sa side to the peripheral side. In other words, the thickness is prevented from increasing rapidly as it approaches the hole region _S1 , and therefore, when the outer cutter is curved and stretched, it bends evenly and there is no risk of cracking or the like.

〔effect〕

As described above, according to the present invention, a flexible rectangular outer cutter base 1 is provided in which the area surrounding the hole area S1 where a large number of hair introduction holes ₂ are present is made into a flat peripheral clearance area _S2 . When forming by the electrodeposition method, an electrically insulating thin film 22 is formed on the main surface of the electrodeposited matrix 21 corresponding to each of the hair introduction holes 2, and the electrically insulating thin film 22 is formed on the main surface of the electrodeposition matrix 21 on one or all surfaces of the matrix 21. After forming the notch 23 in isolation in the electrically insulating thin film 22 and setting the ratio of the surface area of the notch 23 to the surface area of the thin film 22 to be larger at the portion closer to the center Sa side of the base 1, Since electrodeposition is performed on the main surface of the matrix 21, rapid thickness changes in the boundary area between the hole area of the outer cutter base and the peripheral clearance area can be suppressed, and the strength can be increased. The opening area and layout of the electric shaver can be freely set, which has the advantage of providing an electric shaver outer blade with a high degree of freedom in design.

Moreover, in the actual manufacturing process, it is only necessary to add a notch to the mask screen, and there is no need to set up a special process or improve equipment.
A low-cost and efficient manufacturing method can be achieved.

[Brief explanation of drawings]

FIG. 1 is a perspective view showing the outer blade of a reciprocating electric shaver obtained by the manufacturing method of the present invention, and FIGS.
The figure is a sectional view showing the manufacturing method of the outer cutter in order of steps. DESCRIPTION OF SYMBOLS 1... Outer blade base, 2... Hair introduction hole, 21... Electrodeposition matrix, 22... Electrically insulating thin film, 23... Notch, S ₁ ... Hole area, S ₂ ... Surrounding space Area, S ₃ …
...border area, Sa...central area.

Claims (1)

[Claims] 1 In forming a flexible rectangular outer blade base 1 with a flat peripheral margin area _S2 surrounding the hole area S1 where a large number of hair introduction holes ₂ are present, each of the above-mentioned Electroplated matrix 2 corresponding to hair introduction hole 2
1, an electrically insulating thin film 22 is formed on the main surface of the matrix 21, a notch 23 is formed isolated in the electrically insulating thin film 22 on a part or all of the surface of the matrix 21, and the surface area of the thin film 22 is Notch 23 for
The outer blade of a reciprocating electric shaver is characterized in that the ratio of the surface area of the base body 1 is set to be larger in the portion closer to the center Sa side, and then electrodeposition is performed on the main surface of the mother mold 21. manufacturing method.