A first embodiment of the present invention is explained with reference to
As shown in
At an upper end of the main unit 1, a pair of drivers 7 protrudes. A pair of inner cutters 4 of the electric shaver (hereinafter, simply “inner cutter”) that is detachably attached to the drivers 7 are reciprocated integrally with the drivers 7 that are driven by a motor (not shown). In the state where the outer cutter cassette 2 is set on the main unit 1, the inner cutters 4 respectively slide along inner surfaces of outer cutters 3 that are arranged at the upper end of the corresponding net cutter cassettes 6 in reciprocation. This reciprocating electric shaver cuts hairs such as beard that enter through cutter holes (not shown) of the outer cutters 3 by sandwiching with edge portions of the cutter holes of the outer cutters 3 and a plurality of cutting pieces 8 provided in the inner cutters 4. The drivers 7 constitute a driving unit 31 together with the motor.
The structure of the inner cutter 4 is explained in detail. As shown in
The inner cutter unit 10 is formed by bending a metal plate into an arch by a press. In the inner cutter unit 10, the multiple cutting pieces 8 in a U-shape are arranged in a row by forming a plurality of slit holes 12 in an upper portion 10a having a convex substantially-arc-shaped section. Moreover, in the inner cutter unit 10, a lower portion 10b that is a portion extended downward respectively from both bottom ends of the upper portion 10a serves as a pair of the supporting walls 9. In other words, both ends 8c of the cutting pieces 8 are fixed to a pair of the supporting walls 9.
In the present embodiment, the direction in which the cutting pieces 8 are arranged in a row (in other words, the direction in which the inner cutters 4 slide in reciprocation) is referred to as a right and left direction, and the direction perpendicular to the right and left direction and an up and down direction is referred to as a front and rear direction.
As shown in
On both sides of the cutting pieces 8 arranged in a row in the right and left direction, guard pieces 13 that are wider than the cutting pieces 8 are arranged. The guard pieces 13 are formed in a U-shape similarly to the cutting pieces 8, and both ends in the longitudinal direction are integrally supported by a pair of the supporting walls 9. By being arranged at both ends, the gourd pieces 13 connect the entire inner cutter unit 10 robustly so that the cutting pieces 8 are not damaged by an external shock.
In each of the supporting walls 9, a rectangular concave portion 16 that opens downward in a substantially rectangular shape is provided at a central part in the right and left direction. On both sides of each rectangular concave portion 16, circular concave portions 15 that open downward in a substantially circle shape are provided. From the inner circumference of the circular concave portion 15, a plurality of thin convex portions 27 project inwardly. Moreover, above the circular concave portion 15 positioned at the outer side of a pair of the circular concave portions 15 corresponding to each of the rectangular concave portions 16, a rectangular window 17 in a form of rectangular hole is provided at substantially center of the supporting wall 9 in the up and down direction.
The joint member 11 is long in the right and left direction within such length that can almost be housed inside the inner cutter unit 10. The joint member 11 is constituted of a main unit attaching portion 18 and inner cutter fixing portions 19 positioned both sides of the main unit attaching portion 18. The joint member 11 is formed with resin. In the joint member 11, rectangular convex portions 20 formed in a rectangular pillar shape project downward at a central part on both surfaces respectively facing front and rear. Furthermore, in the joint member 11, on the right and left sides thereof, heat seal bosses 21 in a cylindrical shape project. Above the heat seal boss 21 positioned away from the main unit attaching portion 18 of a pair of the heat seal bosses 21, a hollow portion 23 is formed. In addition, above this heat seal boss 21, a connecting hook 24 having a hook portion 24a is provided. A part of the hook portion 24a projects out from the hollow portion 23. In the upper end portions at right and left ends of the joint member 11, finger placing portions 25 as a portion picked at the time of attaching and detaching the inner cutter 4 to and from the main unit 1 are provided. From the upper portion of each of the finger placing portions 25, a protrusion 26 is extended above. The joint member 11 constitutes a base portion 33 together with a pair of the supporting walls 9 of the inner cutters 4.
Furthermore, on the upper surface of the joint member 11, the plate members 32 are integrally formed so as to project from the upper surface of the joint member 11. The plate member 32 includes a plate main body 32a and a cutting piece connecting portion 32b that is continuously provided at the upper end thereof. The plate members 32 are arranged in plurality (in the present embodiment, six pieces) keeping an interval between each other so as to be positioned under the cutting pieces 8 of the inner cutter unit 10. As shown in
As shown in
The upper end of the cutting piece connecting portion 32b is positioned closer to the inner circumference of the cutting edge 8 than an outer surface 8e of the curvature top portion 8b of the cutting piece 8. Specifically, a distance between the outer surface 8e of the cutting piece 8 and the cutting piece connecting portion 32b is 0.05 mm or more. Thickness in the right and left direction of the upper portion of the cutting piece connecting portion 32b is thicker than thickness in the right and left direction of the curvature top portion 8b and the plate main body 32a, and the lower portion of the cutting piece connecting portion 32b is tapered such that thickness of the bottom end thereof becomes the same thickness as that of the plate main body 32a. With this structure, in the plate member 32, thickness of the bottom end is thinner than thickness of the upper end.
As shown in
Furthermore, the position at which the bottom end of the plate member 32 and the base portion 33 (supporting wall 9) are fixed and the position at which the upper end of the plate member 32 and the cutting piece 8 are connected are shifted along the right and left direction (sliding direction). Moreover, rigidity of the plate member 32 is lower than rigidity of the cutting piece 8.
A connecting structure of the inner cutter unit 10 and the joint member 11 structured as above is explained. The inner cutter unit 10 and the joint member 11 are connected by heat sealing the heat seal boss 21 of the joint member 11 in such a state that the heat seal boss 21 is engaged in the circular concave portion 15 of the inner cutter unit 10. The bottom surface of the hook portion 24a of the connecting hook 24 of the joint member 11 is locked at the lower inner side surface of the rectangular window 17 of the inner cutter unit 10, thereby preventing the inner cutter unit 10 from escaping upward from the joint member 11. Furthermore, the rectangular convex portion 20 of the joint member 11 engages in the rectangular concave portion 16 in a pair of the supporting wall 9, thereby positioning the inner cutter unit 10 with respect to the joint member 11 in the right and left direction. Moreover, convex surfaces 22a of contact convex portions 22 formed on a front surface and a rear surface contacts inner surfaces of the supporting walls 9 of the inner cutter unit 10, thereby achieving positioning in the front and rear direction.
In such a structure, when hairs that have entered through the cutting holes of the outer cutter 3 are cut by sandwiching with the edges of the cutting holes and the curved portion 8a of the cutting pieces 8 of the inner cutters 4 that are slid in reciprocation along the inner surface of the outer cutter 3, the cutting pieces 8 are bent (elastically deformed) due to contact with the hairs that have entered through the cutting holes. At the time of cutting the hairs, the bend of the cutting pieces 8 are released (recovered) and the cutting pieces 8 vibrate to make the shaving sound. At this time, in the present embodiment, the plate member 32 whose bottom end is fixed to the base portion 33 and whose upper end is connected to the cutting piece 8 is elastically deformed corresponding to the elastic deformation of the cutting piece 8 to vibrate in a similar manner as the cutting piece 8. Therefore, compared to the case where the plate member is supported in the cantilever structure, the plate member 32 can vibrate more air. As a result, it is possible to make the shaving sound significantly louder and to realize comfortable shaving for users.
Moreover, in the present embodiment, as described above, the upper end of the plate member 32 and the curvature top portion 8b of the cutting piece 8 overlap with each other in the right and left direction (sliding direction). Therefore, even if the cutting piece 8 is bent much in the sliding direction, connection between the cutting piece 8 and the plate member 32 can be maintained, thereby securing reliability in connection between the cutting piece 8 and the plate member 32.
Furthermore, in the present embodiment, as described above, a distance between the outer surface 8e of the cutting piece 8 and the cutting piece connecting portion 32b is 0.05 mm or more. Therefore, the upper end of the plate member 32 does not disturb cutting hairs at the upper edges of the cutting piece 8, thereby ensuring cutting sharpness.
Moreover, in the present embodiment, as described above, rigidity of the plate member 32 is lower than rigidity of the cutting piece 8. Therefore, the plate member 32 is easily bent compare to the structure where the rigidity of the plate member is higher than the rigidity of the cutting piece 8. Therefore, it is possible to make increase in rigidity of the cutting piece 8 to which the plate member 32 is connected small, and to increase a bend amount of the cutting piece 8. Accordingly, the shaving sound can be certainly made louder.
Furthermore, in the present embodiment, as described above, the plate member 32 is formed such that thickness at the bottom end is thinner than thickness at the upper end. Therefore, the plate member 32 is easily bent as a whole. Accordingly, vibration volume increases, thereby enabling to make the shaving sound louder.
Moreover, in the present embodiment, as described above, the plate member 32 and the cutting piece 8 are arranged so as to enable relative movement along an inside-outside direction (up and down direction) of the curvature top portion 8b of the cutting piece 8. Therefore, it is possible to keep the increase in rigidity of the cutting piece 8 caused by connection with the plate member 32 small. Therefore, the movement of the cutting piece 8 can be made smooth. Accordingly, the shaving sound can be certainly made louder while keeping sharpness of the cutting piece 8.
Furthermore, in the present embodiment, as described above, the plate member 32 is formed with resin. Therefore, the rigidity of the plate member 32 can be kept low compared to the case where the plate member 32 is formed with steel. Therefore, the plate member 32 can be structured to bend easily, and the shaving sound can be certainly made louder.
Moreover, in the present embodiment, as described above, the plate member 32 is connected to the inner circumference of the curvature top portion 8b of the cutting piece 8, and thickness in the right and left direction of the curvature top portion 8b of the cutting piece 8 at the outer circumference is thicker than thickness in the right and left direction of the curvature upper portion 8b at the inner circumference of the curvature top portion 8b. Therefore, a projecting amount of the plate member 32 with respect to the cutting piece 8 in the right and left direction can be made small, thereby ensuring the cutting sharpness at the curvature top portion 8b of the cutting piece 8.
Furthermore, in the present embodiment, as described above, the position at which the bottom end of the plate member 32 and the base portion 33 are fixed and the position at which the upper end of the plate member 32 and the cutting piece 8 are connected are shifted in the right and left direction. Therefore, even when a shock is applied on the inner cutter 4 of the electric shaver due to, for example, a fall and the curved portion 8a of the cutting piece 8 is deformed in the direction of flattening the curvature, the plate member 32 flexibly bends. Therefore, it is possible to suppress an impact force on the cutting piece 8 to suppress the damage of the cutting piece 8.
Moreover, in the present embodiment, as described above, the plate member 32 is not arranged for each of the cutting pieces 8, and the plate members 32 are arranged keeping an interval corresponding to a space between two alternate cutting pieces 8 or larger. Thus, a sufficient space is kept between the plate members 32. Therefore, fewer cut hairs are collected between the plate members 32. In addition, between the plate members 32, through holes that open through the up and down direction are provided so that cut hairs fall down through the through holes. Therefore, fewer hairs are collected around the plate members 32.
Furthermore, in the present embodiment, as described above, the plate members 32 and the joint member 11 are integrally formed with resin. Therefore, it is possible to simplify the structure and to process easily at a low cost, to realize the inner cutter 4 that can cut cleanly and can make large shaving sound.
A manufacturing method of the groove 32c of the plate member 32 is explained.
While heating the cutting piece connecting portion 32b′ by transmission of heat to the cutting piece connecting portion 32b′ by heating the curvature top portion 8b of the cutting piece 8 with a heater (not shown), the inner cutter unit 10 is further moved downward until the upper end of the protrusion 26 of the joint member 11 contacts the bottom end of the gourd piece 13 to achieve the positioning of the inner cutter unit 10 and the joint member 11 in the up and down direction. Thus, the upper end of the plate member 32′ is pressed to the cutting piece 8.
At this time, the cutting piece connecting portion 32b′ of the plate member 32′ is thermally deformed by being pressed by the bottom end of the cutting piece 8 in the heated state, and the upper end of the plate member 32′ bites into the curvature top portion 8b of the cutting piece 8. Thus, the groove 32c is formed in the cutting piece connecting portion 32b, and the upper end of the plate member 32 and the curvature top portion 8b of the cutting piece 8 overlap with each other in the right and left direction as shown in
As described above, in the present embodiment, the upper end of the plate member 32 is pressed relative to the cutting piece 8 while being heated to form the groove 32c. Therefore, even if the pitch of the cutting pieces 8 and the pitch of the plate members 32 relatively vary, the variation can be absorbed. Accordingly, the cutting pieces 8 and the plate members 32 can easily be connected to each other. Moreover, it is possible to surely form the state in which all of the plate members 32 are overlapped with the cutting pieces 8 without applying a twist or modification to the cutting pieces 8.
A second embodiment of the present invention is explained with reference to
The present embodiment differs from the first embodiment in the connecting structure of a plate member 132 and the cutting piece 8. Specifically, in the present embodiment, by pressing the upper end of the plate member 132 to the curvature top portion 8b from one side by a restoring force of the plate member 132 that has been bent, the other end of the plate member 132 is connected to the cutting piece 8.
With this structure, the plate member 132 is engaged with the cutting piece 8 in the right and left direction, and is connected so as to enable relative movement in the up and down direction. Thus, also in the present embodiment, the plate member 132 is elastically deformed corresponding to the elastic deformation of the cutting piece 8, and vibrates in a similar manner as the cutting piece 8. Therefore, compared to the case where the plate member is supported in the cantilever structure, the plate member 32 can vibrate more air. As a result, it is possible to make the shaving sound significantly louder.
Moreover, with this structure, the inner cutter 4 can be structured simply, and the number of assembly process of the plate members 132 and the cutting pieces 8 at the manufacturing can be reduced, as compared to the case where the plate members 132 are bonded to the cutting pieces 8.
A third embodiment of the present invention is explained with reference to
The present embodiment differs from the first embodiment in the connecting structure of a plate member 232 and the inner cutter 4. Specifically, a right and left pair of protruding pieces 232d are provided at the upper end of the plate member 232 at positions shifted from each other in the longitudinal direction of the cutting piece 8, to form an engaging portion 232e. With this engaging portion 232e, the curvature top portion 8b of the cutting piece 8 is sandwiched. With this structure, the plate member 232 is engaged with the cutting piece 8 in the right and left direction, and is connected to enable relative movement in the up and down direction. The engaging portion 232e is formed in advance prior to the connection of the plate member 232 and the cutting piece 8.
Moreover, in the present embodiment, a plurality of (in this embodiment, three units) the plate units 241 in which two pieces of the plate members 232 are integrally formed are provided separately from the joint member 11, and it is structured such that the plate units 241 are fixed to the joint member 11 by engagement.
With this structure, also in the present embodiment, the plate member 232 is elastically deformed corresponding to the elastic deformation of the cutting piece 8, and vibrates in a similar manner as the cutting piece 8. Therefore, compared to the case where the plate member is supported in the cantilever structure, the plate member 32 can vibrate more air. As a result, it is possible to make the shaving sound significantly louder.
Furthermore, in the present embodiment, the plate member 232 and the cutting piece 8 are connected by engaging the engaging portion 232e, which is formed in advance, with the cutting piece 8. Therefore, the number of assembly process of the plate members 232 and the cutting pieces 8 at the manufacturing can be reduced compared to, for example, the case where the plate members 232 are bonded to the cutting pieces 8.
A fourth embodiment of the present invention is explained with reference to
The present embodiment differs from the first embodiment in that a space is provided between the bottom surface of the groove 32c of the plate member 32 and the lower surface of the cutting piece 8. This groove 32c is formed in advance prior to the connection of the plate member 32 and the cutting piece 8.
With this structure, the error in the forms in the up and down direction thereof can be absorbed at the time of connecting the plate member 32 and the cutting piece 8. Therefore, the plate member 32 and the cutting piece 8 can be connected easily.
The present invention is not limited to the above embodiments, and other embodiments can be made without departing from the scope of the invention.
For example, the plate member and the cutting piece can be connected by bonding while the plate member and the cutting pieces are struck to each other. Thus, the relative variation in the pitch of the cutting piece and the pitch of the plate member can be absorbed. Therefore, it is possible to simplify the assembly work.
Furthermore, by opening a through hole in the right and left direction at a central part of the plate main body of the plate member, or by providing a groove that opens downward from the bottom end to the central part of the plate main body in the right and left direction, it is possible to make hairs less likely to be collected around the plate members.
Moreover, the bottom ends (both ends in the longitudinal direction) of the cutting piece and the bottom end of the plate member can be positioned at the same level.
Number | Date | Country | Kind |
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2006-121232 | Apr 2006 | JP | national |