JP3427213B2 - Inner blade of reciprocating electric razor - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a reciprocating electric shaver, and more particularly to an inner blade for a reciprocating electric shaver in which the outer blade is curved even in the reciprocating direction of the inner blade.

[0002]

2. Description of the Related Art In a reciprocating electric shaver, an outer blade is generally curved only in a direction orthogonal to the reciprocating direction of the inner blade, and has an arcuate cross-section that is not curved in the reciprocating direction of the inner blade. However, in this case, when shaving the hair in a recessed area such as the submandibular region or the armpit, the outer blade does not adhere to the skin, and thus the hair cutting efficiency is greatly reduced.

For this reason, as disclosed in Japanese Patent Publication No. 57-53748, the outer blade is curved even in the reciprocating direction of the inner blade, and the inner blade slidably contacts the inner surface of the outer blade.
There is a reciprocating electric shaver in which the envelope of the upper end in the reciprocating direction is arcuate and the inner blade reciprocates along the inner surface of the outer blade.

[0004]

Here, the inner blade is usually composed of an inner blade base and a large number of inner blade blades supported by the inner blade base. When the blades are arranged radially so as to be orthogonal to the curved surface of the blade, it becomes impossible to form the inner blade by simultaneously molding the inner blade blade and the inner blade base made of synthetic resin. And for simultaneous molding, when the inner blades are arranged in parallel, the upper end of the inner blade that slides against the inner surface of the outer blade
Inner blade so that the envelope in the reciprocating direction of
When the upper edge of the blade is ground , the blade edge angle on one side of the reciprocating movement of the inner blade (sliding on the outer blade of the inner blade)
Although the upper end surface in contact with the side surface becomes a cutting edge angle) is 90 ° or less formed by the opposite side edge angle becomes 90 ° or more, sharpness is poor, drawback pulling the hairs occurs.

The present invention has been made in view of the above points, and an object thereof is to easily form an inner blade in a case where the outer blade is curved in the reciprocating direction of the inner blade, Moreover, it is to provide an inner blade of a reciprocating electric razor having a good sharpness.

[0006]

SUMMARY OF THE INVENTION The present invention, however, includes an outer blade having a large number of blade holes, and an inner blade which is reciprocally driven and slidably contacts the inner surface of the outer blade, and the outer blade reciprocates. Reciprocating at the upper edge of the inner blade , which is curved in the direction and makes sliding contact with the inner surface of the outer blade
In a reciprocating electric shaver in which the inner blade having an arcuate envelope in the moving direction reciprocates along the curved surface of the outer blade, supports a large number of parallel inner blades and these inner blades. Inner blade blade in the inner blade consisting of the inner blade base, on the surface of one side in the reciprocating direction,
Contrast with the normal of the arc-shaped envelope that connects the cutting edge of each inner blade
In addition to having a rake angle , this normal direction
Shaped on the side of the inner blade to set the rake angle against
The formed recess is outward from the center of the inner blade, facing both ends of the reciprocating motion.
The feature is that it is provided on the surface of the armor .

[0007]

According to the present invention, the outer cutter is arranged in the reciprocating direction of the inner cutter.
Reciprocating motion of the upper edge of the inner blade that is curved and slidably contacts the inner surface of the outer blade
The envelope in the direction is arcuate> The inner blade is the outer blade
Even in the case of reciprocating along the curved surface, the inner blade
While arranging the blades in parallel, set the blade angle of the inner blade to 9
It can be kept at 0 ° or less.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below with reference to the illustrated embodiments. As shown in FIG. 3, this electric shaver has a plurality of outer blades 1 and a plurality of outer blades 1 each formed as a net blade having a plurality of blade holes. A trimmer blade composed of a comb-shaped fixed blade 3 and a movable blade 4 is provided on both sides of a main blade M composed of an inner blade 2 having an inner blade blade 21 formed on the inner blade base 20. T, T
Are formed by arranging each of them.

As shown in FIG. 4, the outer blade 1 of the main blade M here is not only curved in the direction Y orthogonal to the reciprocating direction X of the inner blade 2, but also in the reciprocating direction X of the inner blade 2. Is also curved, and is attached to the outer blade frame 15 formed in a rectangular frame shape. This attachment is performed by inserting a plurality of attachment bosses 16 protruding from the outer cutter frame 15 into the attachment holes 10 provided on both sides of the outer cutter 1. At this time, the mounting holes 10 located at both ends of the outer blade 1 in the reciprocating direction of the inner blade 2
Only the mounting boss 16 inserted into the mounting hole 10 is heat crimped, and the other mounting bosses 16 are simply inserted into the mounting hole 10. This is to make the curvature of the outer blade 1 in the reciprocating direction of the inner blade 2 smooth and to have a required radius of curvature R1, and the arc of the radius of curvature R3 connecting each mounting boss 16 is the outer blade 1. The reason why it has the same center as the arc having the above-mentioned radius of curvature R1 is that the notch 11 is formed at both ends of the outer cutter 1 in the center of the inner cutter 2 in the reciprocating direction and in the direction orthogonal to the reciprocating direction. It is provided for the same reason.

The outer blade frame 15 to which the outer blade 1 is attached in this manner is attached to the blade frame 8 shown in FIG. The blade frame 8 in the shape of a rectangular tube that opens vertically is provided with locking projections 83 and inclined surfaces 84 located below the locking projections 83 on the inner wall surfaces at both ends in the longitudinal direction.
If the outer blade frame 15 having the elastic pieces 18 protruding from both ends in the longitudinal direction and having the flat portions 17 on the upper surfaces of both ends is pushed in from the lower side of the blade frame 8, as shown in FIG. Is in a state in which the flat portion 17 is brought into contact with the lower surface of the locking projection 83 by the upward biasing force generated by the tip of the elastic piece 18 coming into contact with the inclined surface 84.
The outer blade frame 15 is attached to the blade frame 8 without rattling, and at the same time, it is prevented from being accidentally detached from the blade frame 8 when the blade frame 8 is detached and cleaned.

On the other hand, the inner blade 2 has a large number of inner blades 21.
Are formed in parallel with each other on the upper surface of the inner blade base 20, and the inner blade blades 21 connect the upper ends of the inner blade blades 21 as shown in FIG. After being planted so that the envelope has an arc 2a having a certain radius of curvature, it is ground to the point where the arc having the radius of curvature R4 shown in FIG. 2b becomes the envelope connecting the upper ends. In this case, the cutting edges located on both sides of the tip of each inner blade 21 are 90 ° or less on the one hand, but 90 ° or more on the other hand, but here, in order to keep the cutting edge angle at an acute angle.
Recessed part for setting rake angle 26
When the blade is provided on the side surface of the inner blade 21, a peg portion 26 having different directions on one side and the other side in the reciprocating direction is provided. The direction of each piling portion 26 is set to be outward.

[0012] The rake angle β is set by the provision of such a beating portion 26.
The rake angle β is set to be larger than the opening angle α (see FIG. 1) from the center of the cutting edge radius R4 of the inner blades 21 located at both ends. That is, even with respect to the normal line of the envelope 2b,
It has a rake angle δ, and the cutting edge angle γ is 90 ° or less. As a result, the total inner blade 21
Although the rake angle β is common and the same rake angle can be used, the cutting edge angles are all 90 ° or less. It should be noted that, because the beveled portions 26 have the same rake angle β, the cutting edge angle of the inner blade blade 21 located on the center side of the inner blade base 20 is smaller than the cutting edge angle of the inner blade blades 21 located at both ends. It is sharp.

The inner blade 2 thus formed is shown in FIG.
It is reciprocally driven by the driver 7 shown in FIG. A vertically middle portion is pivotally supported by a pin 70 so as to be swingable, and a cam groove 71 with which an eccentric shaft 77 with a balancer attached to an output shaft of a motor 76 engages is provided at a lower end. The driving element 7 in which the inner blade 2 is connected to the upper end swings around the pin 70 as the motor 76 rotates.

The drive element 7 and the inner blade 2 are connected to each other by projecting from the inner blade base 20 in the upper end portion of the drive element 7 which is cylindrical and in which the compression coil spring 25 is housed. The connecting boss 22 is inserted, and the engaging portion 23 protruding on both sides of the connecting boss 22 and the hook 72 provided on the upper end of the driver 7 are prevented from coming off. The joint portion 23 is located in a vertically long groove 73 in the driver 7, and the inner blade 2 is slidable within a predetermined range in the axial direction of the driver 7.

The inner blade 2 of the main blade M constructed as described above reciprocates along an arcuate locus along the inner surface of the outer blade 1 when the motor 76 is rotated. Two
In order to make the reciprocating movement of the inner blade 2 smooth, here, the drive radius R2 of the inner blade 2, that is, the pin 70 supporting the driver element
To the edge of the inner blade 2 at the center of the inner blade 2 is smaller than the radius R1 of the outer blade 1.

As shown in FIG. 6, a pair of trimmer blades T arranged on both sides of the main blade M are fitted with a base 5 and a fitting projection 57 on the curved upper surface of the base 5. And a movable blade 4 arranged on the upper surface side of the fixed blade 3 and slide-guided by the fitting protrusion 57.
And a pressing spring 65 that presses the movable blade 4 toward the fixed blade 3 side.
When the vertical flat plate portion 66 of the pressing spring 65 is attached to the cover 6 by engagement with the spring stop projection 60, and the cover 6 is attached to the base 5 by the hook 61, With the vertical flat plate portion 66 sandwiched and fixed between the cover 6 and the base 5, a plurality of spring pieces 6 are provided.
7 is brought into contact with the upper surface of the movable blade 4.

Further, the base 5 has a pair of locking pieces 50, 50, a pair of hooks 52, 52, and a pair of locking pieces 51, 51 projecting downward, and at the center thereof. The trimmer driver 54 supported by the pair of thin elastic pieces 53, 53 is provided, and the two pairs of locking portions 8 formed on the inner wall surface of the blade frame 8 in the lateral direction.
The locking pieces 50 and 51 are inserted into the blades 1 and 82, and the trimmer driver 54 is pivotally supported by the support shaft 80, whereby the trimmer driver 54 is attached to the blade frame 8. However, of both trimmer blades T, the trimmer driver 5 of one trimmer blade T
The support shaft 80 that supports 4 is provided on a slide button 85 that is vertically slidably attached to the blade frame 8, and the engagement between the engaging portions 81 and 82 and the engaging pieces 50 and 51 is up and down. In addition to being slidable, one of the trimmer blades T also slides up and down as the slide button 85 slides up and down.

The lower end of the trimmer driver 54, whose upper end is an engaging portion 55 for engaging the movable blade 4, engages with the drive projection 75 provided on the driver 7, and the driver 7
Engaged portion 56 whose movement is transmitted to the trimmer driver 54
Has become. When the driver element 7 swings, the trimmer driver element 54 swings around the support shaft 80 and is also formed in a comb tooth shape with respect to the fixed blade 3 formed in a comb tooth shape. The movable blade 4 is slid back and forth. The engaging portion 55 and the engaged portion 56 are positioned on the same straight line in the vertical direction so that the trimmer driver 54 is not easily twisted.

Here, from the support shaft 80 to the engaged portion 8
As shown in FIG. 3, the length L1 up to 5 is shorter than the length L2 from the support shaft 80 to the engaging portion 80. Therefore, although power is taken from the middle of the driver element 7, Movable blade 4
The reciprocating stroke is long enough. Also,
With respect to the trimmer blade T on the side supported by the support shaft 80 of the slide button 85, the driver 7 has two upper and lower drive protrusions 7.
5 and 75, the upper drive projection 75 is engaged with the engaged portion 56 when the slide button 85 is moved upward to move the trimmer blade T upward. However, at this time, the swing strokes of the upper and lower two drive projections 75, 75 are different, and the swing stroke of the upper drive projection 75 is larger than that of the lower drive projection 75. The vertical distance E between the two drive projections 75, 75 is made smaller than the vertical slide amount of the slide button 85 so that the reciprocating stroke of the movable blade 4 does not change even if the trimmer blade T is moved up and down.

Further, the trimmer blade T here cuts hair in cooperation with the main blade M, that is, long hair is trimmer blade T.
In order to smoothly perform the operation of cutting the short bristles after cutting with the trimmer blade T with the main blade M, the trimmer blade T in the reciprocating direction of the inner blade 2 in the main blade M can be smoothly operated. Is also curved,
At this time, the ridgeline of the outer blade 1 of the main blade M and the sliding surface of the trimmer blade T between the movable blade 4 and the fixed blade 3 are kept at a constant distance D throughout.

FIG . 8 shows another embodiment. Upon this means using inner cutter blade 21 having a rake angle on only one side, reciprocating only inner cutter blade 21 located opposite end to that shall have a rake angle on the inside, also the inner cutter blade across 21 Only the blade edge angle outside is set to 90 ° or more. This is because when the inner blade 2 is reciprocated in an arc along the curvature of the outer blade 1, the inner blade blades 2 at both ends of the inner blade 2 are moved.
In view of the fact that 1 tends to stick to the outer blade 1 and the inner blade 2 floats from the outer blade 1, the outer cutting edge angle of the inner blade blades 21 at both ends caught in the outer blade 1 is obtuse. By setting it, it is possible to prevent it from getting stuck. Inner blade breaks located at both ends of the inner blade 2 in the reciprocating direction
By tilting only the blade 21 inward, the inner blades at both ends
Only the outer edge angle of 21 should be larger than 90 °
You may.

[0022]

As described above, in the present invention, the outer blade is
The outer blade is curved in the reciprocating direction of the inner blade as well.
Envelope in the reciprocating direction of the upper edge of the inner blade slidingly contacting the inner surface
Is an arc shape, and the inner blade is reciprocated so that it follows the inner surface of the outer blade.
In spite of being able to make it, it is possible to make it easy to form the inner blades in parallel and at the same time,
The blade angle of the inner blade can be maintained at 90 ° or less, and it is possible to improve productivity and secure sharpness by simultaneous molding with the inner blade base of the inner blade.

[Brief description of drawings]

FIG. 1 shows an embodiment, (a) is a front view of an inner blade,
(b) is an enlarged view of part A.

FIG. 2 is a vertical sectional view of the above.

FIG. 3 is a transverse sectional view of the above.

FIG. 4 is an exploded perspective view of the main blade of the above.

FIG. 5 is an exploded perspective view of the above-mentioned motor and driver.

FIG. 6 is an exploded perspective view of a pair of trimmer blades of the same.

FIG. 7 is a cutaway perspective view of the above blade frame.

FIG. 8 shows another example, (a) is a front view and (b) is an enlarged sectional view.

[Explanation of symbols]

2 inner blade 20 Inner blade base 21 Inner Blade γ Cutting edge angle

─────────────────────────────────────────────────── ─── Continuation of front page (56) Reference JP-A-58-209375 (JP, A) JP-A-4-352988 (JP, A) JP-A-4-343883 (JP, A) Actual development Sho-50- 3788 (JP, U) S. 54-6638 (JP, Y1) S. 36-2442 (JP, Y1) (58) Fields investigated (Int.Cl. ⁷ , DB name) B26B 19/04

Claims (3)

(57) [Claims] 1. An outer blade having a large number of blade holes, and an inner blade that is reciprocally driven to slidably contact the inner surface of the outer blade, and the outer blade is curved in the reciprocating direction of the inner blade and slides on the inner surface of the outer blade. Touch
The inner edge of the inner blade in the reciprocating direction has a circular arc shape.
In a reciprocating electric shaver in which the inner blade is reciprocating along the curved surface of the outer blade, an inner blade consisting of a number of inner blades arranged in parallel and an inner blade base supporting these inner blades. Inner blade blade in, on the surface of one side in the reciprocating direction, with a rake angle to the normal of the arc-shaped envelope connecting the blade tips of each inner blade,
In order to set the rake angle for this normal direction,
Reciprocating the recess formed on the side of the blade from the center of the inner blade
Inner blade of a reciprocating electric razor, which is provided on the outer surface facing both ends of . 2. Inner blade blades located at both ends in the reciprocating direction
The inner blade of the reciprocating electric shaver according to claim 1, wherein only the angle of the outer cutting edge is 90 ° or more . 3. Inner blade blades located at both ends in the reciprocating direction
Has no rake angle on its outer surface
The inner blade of the reciprocating electric razor according to claim 2 .