JP4807736B2 - Electric razor and method of manufacturing inner blade - Google Patents

Description

  The present invention relates to an electric razor including an outer blade in which a sheet-shaped mesh blade is held in an arch shape, and an inner blade that is rotationally driven around a horizontal axis while being inscribed in the outer blade, and a method for manufacturing the inner blade About.

  Patent Document 1 discloses an electric razor in which an inner blade small blade is disposed on the outer peripheral surface of the body portion of the inner blade, and the inner blade small blade extends in a spiral shape in the length direction of the body portion. Yes.

  In Patent Document 1, it is described that the thickness of the base end side of the inner blade small blade is made larger than that of the blade edge portion, and the cutting resistance received from the ridge as much as the thickness of the inner blade small blade can be increased. Therefore, the bending of the inner cutter blade can be reduced. In addition, by reducing the wall thickness of the blade edge part of the inner blade small blade, it is difficult for the portion other than the blade edge to hit the inner surface of the fixed outer blade at the blade edge portion of the inner blade small blade, and the outer blade is damaged by the portion other than the blade edge. Can be prevented.

Japanese Patent Laid-Open No. 4-322629 (paragraph number 0027, FIG. 1-2) Japanese Utility Model Publication No. 59-125372 (Fig. 1-2) Japanese Patent Laid-Open No. 51-44068 (FIG. 6)

  In Patent Document 1, a separate accessory plate is attached and fixed to the base end side of the inner blade edge, and the thickness dimension of the inner edge blade is increased, and only the attachment plate is attached. It takes time to manufacture the inner blade.

  Patent Document 1 also describes that the inner blade edge is formed so as to increase the thickness of the base end side in place of the attached plate. However, in this case, since the thickness dimension of the cutting edge portion of the inner blade small blade is reduced by cutting or the like, it takes time to manufacture the inner blade by the amount of the cutting.

  Accordingly, an object of the present invention is to provide an electric razor that can increase the thickness of the base end side of the inner cutter blade while reducing the labor of processing.

  As shown in FIGS. 1 and 2, the electric razor targeted by the present invention includes an outer blade 15 in which a sheet-like mesh blade is held in an arch shape, and a horizontal axis 21 around the outer blade 15. And an inner blade 13 that is rotationally driven.

As shown in FIGS. 1 and 3, the electric shaver of the present invention includes an inner blade 13 having a columnar body portion 23, the horizontal shaft 21 arranged on the axis of the body portion 23, and an outer peripheral surface of the body portion 23. And an inner blade small blade 25 extending in the length direction of the body portion 23, and the inner blade small blade 25 has a protruding end from the body portion 23 of the inner blade 13 rather than the base end side. It is implanted in the trunk portion 23 in a forward leaning posture that precedes in the rotational direction. An edge 36 having a concave curved surface that is recessed in the thickness direction of the inner cutter blade 25 is formed on the cutting edge portion 25 a of the protruding end of the inner cutter blade 25. Due to the presence of the edge 36, the blade edge portion 25a associated with the protruding end of the inner blade small blade 25 from the body portion 23 is formed in a tapered shape that gradually decreases in thickness as it approaches the protruding end. Yes. The inner blade edge 25 is formed by forming a corrosion-resistant resist film 35 matching the outer shape of the inner edge blade 25 on the upper surface of a flat metal plate, and then removing the resist film 35. Is removed by etching from above. The edge 36 is an etched surface formed on the periphery of the metal plate corresponding to the inner blade edge 25 during the etching process.

A blade edge 25b that is inscribed in the outer blade 15 is formed in a flat shape on the blade edge portion 25a of the protruding end of the inner blade small blade 25. A concave curved edge 36 that is recessed in the thickness direction of the inner cutter blade 25 is formed between the rear wall surface of the inner cutter blade 25 and the rear edge of the blade edge 25b. Due to the presence of the edge 36, the cutting edge portion 25a of the inner cutting edge blade 25 is formed in a tapered shape that gradually decreases in thickness as it approaches the cutting edge 25b.

On the front wall surface of the inner cutter blade 25, a concave curved edge 36 that is recessed in the thickness direction of the inner cutter blade 25 is formed. Due to the presence of the edge 36, the cutting edge portion 25a of the inner cutting edge blade 25 is formed in a tapered shape that gradually decreases in thickness as it approaches the cutting edge 25b.

The present invention is a method for manufacturing an inner blade including a columnar body portion 23 and an inner blade small blade 25 that is fixed to the outer peripheral surface of the body portion 23 and extends in the length direction of the body portion 23. A concave curved edge 36 that is recessed in the thickness direction of the inner cutter blade 25 is formed on the cutting edge portion 25a of the inner cutter blade 25 that protrudes from the body portion 23 of the inner cutter blade 25. This manufacturing method includes a step of forming a corrosion-resistant resist film 35 that matches the outer shape of the inner blade edge 25 on the upper surface of a flat metal plate, and a metal plate excluding the resist film 35 from above. Removing by an etching process. The edge 36 is an etched surface formed on the peripheral edge of the inner blade edge 25 during the etching process.

  According to the present invention, the cutting edge portion 25a of the inner cutting edge small blade 25 is formed so that the thickness dimension decreases as it approaches the cutting edge 25b. Even if it is not attached, the thickness dimension of the base end side of the inner cutter blade 25 can be increased, and the thickness dimension of the cutting edge portion 25a of the inner cutter blade 25 can be decreased.

  In other words, it is possible to increase the rigidity by increasing the thickness dimension of the inner blade small blade 25 while reducing the labor when processing the inner blade 13 as much as it is not necessary to attach the attachment plate or the like, It is possible to prevent the sharpness of the inner blade small blade 25 from being bent due to the resistance received from the heel or the like and the sharpness from being lowered. In addition, as much as the thickness of the blade edge portion 25a can be reduced, it is possible to reliably prevent a portion other than the blade edge 25b of the blade edge portion 25a from hitting the inner surface of the outer blade 15 and damaging the outer blade 15.

  When the cutting edge portion 25a of the inner cutter blade 25 is formed using the concave curved edge 36 formed at the periphery when the inner cutter blade 25 is molded, the inner cutter blade 25 is molded. After the processing, it is not necessary to perform cutting or the like on the inner blade small blade 25 in order to reduce the thickness of the blade edge portion 25a, and the labor for processing the inner blade 13 can be reduced by that amount.

  When etching is performed on the flat plate material 31, the etching proceeds in a mortar shape, so that a concave curved blade edge portion 25 a is automatically formed along the peripheral edge of the inner blade edge 25, and only by that amount. It is possible to reduce time and labor when machining the inner blade 13.

Example 1 FIGS. 1 to 7 show Example 1 of a rotary electric shaver to which the present invention is applied. As shown in FIG. 2, the electric razor is float-supported by an egg-shaped main body 1 that also serves as a grip, a U-shaped support arm 2 that protrudes continuously upward from the main body 1, and the support arm 2. The head unit 3 is provided.

  A circuit board 5 and two secondary batteries 6 are accommodated in the main body 1. A decorative panel 7 is arranged on the front surface of the main body 1, and a push button type switch button 9 above and below it, a first indicator lamp 10 that lights up when the switch button 9 is turned on, and lights up when charging. A second indicator lamp 11 and the like are arranged.

  The head unit 3 transmits a head case 12, a movable inner blade 13 incorporated in the head case 12, a fixed outer blade 15 and an outer blade holder 16, a motor 17 for driving the inner blade, and motor power to the inner blade 13. A gear mechanism 19. The outer blade holder 16 can be removed from the head case 12.

  A pair of left and right support legs 20, 20 are provided on both sides of the lower surface of the head case 12, and by supporting these support legs 20, 20 with a support arm 2 via a float spring, the head portion 3 is formed. It is supported floating so that it can tilt left and right or move up and down simultaneously.

  The movable inner blade 13 is composed of a horizontal rotary blade, and a rotary shaft (horizontal axis) 21 is rotatably supported by an inner blade support base 22 shown in FIG. In the movable inner blade 13, a plurality of spiral inner blade blades 25 are arranged on the outer peripheral surface of a cylindrical body portion 23, and each inner blade blade 25 extends in the length direction of the body portion 23. ing. The rotary shaft 21 is disposed so as to penetrate the shaft core of the body portion 23.

  That is, as shown in FIGS. 3 and 4, the movable inner blade 13 is fixed to the peripheral surface of the plastic body portion 23 with each inner blade small blade 25 having a predetermined twist angle, and the rotating shaft. 21 is insert-molded so that both ends thereof protrude from the body 23. Furthermore, each inner cutter blade 25 is insert-molded in the body portion 23 with a predetermined rake angle (for example, 10 °) as shown in FIG. Each of the inner cutter blades 25 is made of a quenched martensitic stainless steel plate and has a thickness dimension of 0.2 to 0.3 mm.

  As shown in FIG. 1, the fixed outer blade 15 includes a sheet-like mesh blade body 26 formed by electroforming using nickel or a nickel-cobalt alloy, and the rear end side of the opposite edge of the mesh blade body 26 (FIG. 1). A holding frame 27 fixed to the right side) and a tension structure 29 attached to the front end side (left side in FIG. 1) of the opposite edge of the mesh blade body 26. The mesh blade body 26 is held in an arch shape by the outer blade holder 16.

  The tension structure 29 maintains the mesh blade body 26 in a tension state, and the blade edge 25b of the inner blade small blade 25 of the movable inner blade 13 is inscribed in close contact with the inner surface of the mesh blade body 26. A counter sink 26 a is formed in the inner surface of the mesh blade body 26 for the purpose of reducing the sliding load associated with the rotational sliding of the inner blade edge 25. The gear mechanism 19 is constituted by a gear train composed of a spur gear group, and the output shaft 26 of the motor 17 is connected to the gear mechanism 19 as shown in FIG. The movable inner blade 13 is rotationally driven around the rotation shaft 21 while being inscribed in the fixed outer blade 15 by the motor 17.

  In the present embodiment, in the electric shaver having the above-described structure, as shown in FIG. 1, the blade edge portion 25a of the inner blade small blade 25 is formed such that the thickness dimension gradually decreases as it approaches the blade edge 25b (FIG. 1 is the right side of the inner cutter blade 25 rotating counterclockwise).

  Each inner cutter blade 25 processes the material of the flat stainless steel plate material 31 shown in FIG. 6 by a photoetching method. That is, after a film-like photosensitive film is formed on the upper surface of the stainless steel plate material 31, the film-like photosensitive film is exposed and developed using the photomask 33 shown in FIG. In the photomask 33, each arcuate inner blade forming portion 33a is a portion where the inner blade small blade 25 is formed.

  As a result, the exposed portion of the film-like photosensitive film is removed, and a corrosion-resistant resist film 35 is patterned on the upper surface of the stainless steel plate 31 as shown in FIG. The stainless steel plate material 31 on which the resist film 35 is formed is placed on the base 32 and an etching process is performed by spraying an etching solution. For example, ferric chloride is used as the etching solution. When the non-exposed portion of the film-like photosensitive film is set to be removed, the photomask is formed so as to have a negative relationship with the photomask 33 shown in FIG.

  By the etching process, as shown in FIG. 6B, etching that is recessed into a mortar shape proceeds from the open surface 35 a of the resist film 35, and the etching is performed until the base 32 is reached. As a result, each of the inner cutter blades 25 can be extracted from the stainless steel plate material 31, and a concave curved edge 36 is formed on the periphery of the arcuate inner cutter blade 25. The edge 36 forms a blade edge portion 25a of each inner blade small blade 25 having a concave curved surface 37 on the downstream side in the rotation direction of the movable inner blade 13 (right side in FIG. 1).

  In each inner blade forming portion 33a of the previous photomask 33, a plurality of small hole forming portions 33b are formed side by side in the length direction of the inner blade forming portion 33a on the inner periphery (right side in FIG. 5). Thus, after the etching process, as shown in FIG. 3, a plurality of through small holes 25 c are formed in each inner blade edge 25.

  Thereafter, the resist film 35 is removed, and a cutting process from the stainless steel plate material 31 is performed at both ends in the length direction of each inner blade edge 25. That is, each inner blade small blade 25 is extracted from the stainless steel plate material 31 in a shape that matches each inner blade forming portion 33 a of the photomask 33.

  Next, after each inner blade small blade 25 is pressed into a spiral shape, it is insert-molded into the body portion 23 together with the rotating shaft 21. By this molding, as shown in FIG. 7, the molding resin has entered the through small holes 25 c of the inner cutter blades 25, thereby preventing the inner cutter blades 25 from coming off from the body portion 23. Thereafter, the tip of the edge 36 on the cutting edge side of each inner cutting edge 25 is polished to form the cutting edge 25b as shown in FIGS. Moreover, it is finish-ground if necessary. The cutting edge angle is, for example, 80 °.

  Thus, the cutting edge portion 25a of the inner cutting edge blade 25 has the concave curved surface 37 whose thickness is reduced as approaching the cutting edge 25b as the second corner, so that the cutting edge can be maintained while the rigidity of the inner cutting edge blade 25 is kept high. A portion other than the blade edge 25b in the portion 25a can be made difficult to hit the inner surface of the outer blade 15. Further, the scissors that have passed through the mesh of the mesh blade body 26 of the fixed outer blade 15 penetrate deeply into the razor by the amount that is guided along the concave curved surface 37, with the blade edge portion 25a of the inner blade small blade 25 being thin. It is easy to cut reliably.

  Moreover, since the concave curved surface 37 is formed using the concave curved edge 36 formed on the periphery of the inner blade small blade 25 when the inner blade small blade 25 is machined, the cutting edge portion of the inner blade small blade 25 is formed. In order to reduce the wall thickness of 25a, it is not necessary to grind the cutting edge portion 25a after each inner cutter blade 25 is extracted from the stainless steel plate material 31. Further, since the cutting edge 25b is polished as the first corner, the wrinkles are more reliably cut.

  For the resist film 35, various resist film forming methods such as a method of directly irradiating the photosensitive film with a laser beam without using the photomask 33 and curing it can be considered. Each inner cutter blade 25 may be extracted from the stainless steel plate material 31 by press working. In this case, the punching die is manufactured so that the edge 36 of the concave curved surface is formed on the peripheral edge of each inner cutter blade 25.

  In the above description, the through small hole 25c is made to penetrate the inner blade small blade 25, but the through small hole 25c does not necessarily have to penetrate the inner blade small blade 25. Further, instead of the through small hole 25c, as shown in FIG. 8A, a plurality of C-characters are formed on the edge (upper side in FIG. 8A) of the inner blade small blade 25 embedded in the body portion 23. The photomask 33 may be manufactured so that the notch 40 is formed. Also in this case, the molding resin enters the C-shaped cutout 40 to prevent the inner cutter blade 25 from coming off from the body portion 23.

  Further, as shown in FIG. 8B, a plurality of T-shaped protrusions 41 are formed on the edge of the inner blade edge 25 on the side embedded in the body portion 23 (upper side of FIG. 8B). As described above, the photomask 33 may be manufactured. Also in this case, the molding resin enters between the adjacent T-shaped projections 41 to prevent the inner cutter blade 25 from coming off from the body portion 23.

(Example 2) In Example 2, as shown in FIG. 9, the concave curved surface 37 of the blade edge part 25a of the inner blade small blade 25 is directed to the upstream side in the rotation direction of the movable inner blade 13 (left side in FIG. 9). . Further, the inner blade edge 25 has an inclination angle with respect to the circumferential direction of the body portion 23 smaller than that of the first embodiment, and the tip of the edge 36 is left as it is without being polished. Since the other points are the same as those of the first embodiment, description thereof is omitted.

(Example 3) In Example 3, as shown in FIG. 10, while turning the concave curved surface 37 of the blade edge | tip part 25a of the inner blade small blade 25 to the upstream of the rotation direction of the movable inner blade 13 (left side of FIG. 10), The middle part of the upper part of the inner cutter blade 25 protruding from the body part 23 is bent upstream in the rotational direction of the movable inner cutter 13. The inner cutter blade 25 is left as it is without polishing the tip of the edge 36. Since the other points are the same as those of the first embodiment, description thereof is omitted.

Vertical side view showing the main part of an electric shaver to which the present invention is applied External view of electric razor 1 is a longitudinal front view of a movable inner blade according to a first embodiment of the present invention. Vertical side view of the movable inner blade of Example 1 Plan view of a photomask for forming inner blades Sectional drawing for demonstrating the etching process of an inner blade small blade Expanded vertical side view of movable inner blade 8 (a) and 8 (b) are plan views of another embodiment of the inner cutter blade. Longitudinal side view of movable inner blade of embodiment 2 Vertical side view of the movable inner blade of Example 3

Explanation of symbols

13 Movable inner blade 15 Fixed outer blade 21 Rotating shaft 23 Body portion 25 Inner blade small blade 25a Blade edge portion 25b Blade edge 31 Stainless steel plate material 36 Edge

Claims (4)

Comprising a sheet-like net blades and outer blades (15) which is shape-retaining arched, and an inner cutter (13) which is rotated in a state that is inscribed horizontal axis (21) around the said outer blade (15) In electric razor,
The inner blade (13) is a columnar body portion (23), said barrel (23) the horizontal axis Ru disposed axis and (21), is disposed on the outer peripheral surface of the barrel (23) includes an inner blade and cutter blades (25) extending in the longitudinal direction of the body portion (23),
The inner blade small blade (25) is planted in the body portion (23) in a forward inclined posture in which the protruding end from the body portion (23) precedes the base end side in the rotation direction of the inner blade (13). Has been established,
A concave edge (36) that is recessed in the thickness direction of the inner cutter blade (25) is formed on the cutting edge (25a) of the protruding end of the inner cutter blade (25),
Due to the presence of the edge (36), the blade edge portion (25a) associated with the projecting end of the inner cutter blade (25) from the barrel (23) gradually decreases in thickness as it approaches the projecting end. It is formed in a tapered shape,
After the inner cutter blade (25) forms a corrosion-resistant resist film (35) that matches the outer shape of the inner cutter blade (25) on the upper surface of a flat metal plate, The metal plate excluding the film (35) is removed by etching from above ,
Electric shaver said edge (36) is, that during the etching process, and wherein the etching surface der Rukoto formed on the periphery of the metal plate corresponding to the inner blade cutter blades (25). A blade edge (25b) inscribed in the outer blade (15) is formed in a flat shape on the blade edge portion (25a) associated with the protruding end of the inner blade small blade (25) ,
A concave curved edge (36) that is recessed in the thickness direction of the inner cutter blade (25) is formed between the rear wall surface of the inner cutter blade (25) and the rear edge of the blade tip (25b). Has been
The presence of the edge (36) according to the cutting edge portion of the inner blade cutter blades (25) (25a), the gradual thickness dimension toward the cutting edge (25b) is that is formed to be smaller destination Subomari shape Item 1. An electric razor according to item 1. On the front wall surface of the inner cutter blade (25), a concave curved edge (36) that is recessed in the thickness direction of the inner cutter blade (25) is formed,
Due to the presence of the edge (36), the blade edge portion (25a) of the inner blade edge (25) is formed in a tapered shape that gradually decreases in thickness as it approaches the blade edge (25b). Item 1. An electric razor according to item 1. In the manufacturing method of the inner blade including the columnar body (23) and the inner blade small blade (25) that is fixed to the outer peripheral surface of the body (23) and extends in the length direction of the body (23),
A concave curved edge (36) that is recessed in the thickness direction of the inner cutter blade (25) is formed on the blade edge portion (25a) at the protruding end of the inner cutter blade (25) from the body portion (23). Is formed,
Forming a corrosion-resistant resist film (35) that matches the outer shape of the inner cutter blade (25) on the upper surface of the flat metal plate;
Removing the metal plate excluding the resist film (35) from above by an etching process,
The method of manufacturing an inner blade, wherein the edge (36) is an etched surface formed on a peripheral edge of the inner blade small blade (25) during the etching process .

Images