US3842498A

US3842498A - Electric razor

Info

Publication number: US3842498A
Application number: US00282020A
Authority: US
Inventors: S Mizobata; Y Kawano; K Itoh
Original assignee: Matsushita Electric Works Ltd
Current assignee: Panasonic Electric Works Co Ltd
Priority date: 1971-08-26
Filing date: 1972-08-21
Publication date: 1974-10-22
Anticipated expiration: 1991-10-22
Also published as: JPS4832058A; GB1358949A; DE2241384B2; FR2151422A5; DE2241384A1; DE2241384C3

Abstract

Electric razor for cutting hairs with comb-shaped fixed and movable blades at their blade edges exposed out of body case which has a cylindrical gripping part extending in parallel plane with sliding direction of the movable blade and containing therein internal mechanism and power source. Elements of the mechanism such as movable blade driving means, motor and dry cell holding and electric contacting member are mounted to a frame so that the mechanism will be integral structure independent of the body case and mounted to the case through the frame. Blade holding and covering member is detachably mounted to the case at a slanted angle to the case.

Description

Elaited States Patent 1 Mizobata et al.

ELECTRIC RAZOR Inventors: Shire Mizobata; Yoshiro Kawano;

Kenzo ltoh; Takeshi Usui, all of Hikone, Japan Matsushita Electric Works, Ltd., Osaka, Japan Filed: Aug. 21, 1972 Appl. No.: 282.020

Assignee:

Foreign Application Priority Data Aug. 26, 1971 Japan 46-65357 References Cited UNITED STATES PATENTS 9/1932 Sireci 30/220 8/1939 Hoy 30/4392 X [1 1] 3,842,498 [451 Oct. 22,1974

2,773,306 12/1956 Ranson 30/4392 3,035,346 5/1962 Campbell 30/43.)2 X

Primary E.raminerAl Lawrence Smith Assistant Examiner-Gary L. Smith Attorney, Agent, or Firm-Pierce, Scheffler & Parker [57] ABSTRACT Electric razor for cutting hairs with comb-shaped fixed and movable blades at their blade edges exposed out of body case which has a cylindrical gripping part extending in parallel plane with sliding direction of the movable blade and containing therein internal mecha' nism and power source. Elements of the mechanism such as movable blade driving means, motor and dry cell holding and electric contacting member are mounted to a frame so that the mechanism will be integral structure independent of the body case and mounted to the case through the frame. Blade holding and covering member is detachably mounted to the case at a slanted angle to the case.

4 Claims, 8 Drawing Figures PMENTEB 3.8425498 sum 30; 4

ELECTRIC RAZOR This invention relates to electric razors and, in particular, an improvement in the electric razor consisting of a fixed blade having an exposed edge blade extending in comb-shape along the axial line of razor body and a movable blade which is reciprocally slidable while in contact with this fixed blade so as to be of a type of cutting hairs with the exposed edge blade of the fixed blade and the blade tip of the movable blade.

In conventional electric razors of the kind referred to, there have been involved such defects that driving mechanism for the movable blade, motor, dry cell, fittings for holding the cell and the like are substantially separately mounted to the razor case respectively and,

therefore, assembling, inspection, maintenance and the like workings are complicated and the whole structure or configuration is improper for the purpose of easy handling, that many metallic parts are employed in the driving mechanism, which causing many problems such as mechanical noises and wears occurring between such parts, and that disassembling of the razor blade is inconvenient and hence it is difficult to change the blade in respose to the usage of the razor. The present invention has been suggested to provide an improved electric razor in which the above defects are removed.

A main object of the present invention is therefore, to provide an electric razor of a simplified structure which is very easy to assemble and disassemble and has few component parts.

Another object of the present invention is to provide an electric razor of a configuration by which hair cutting or shaving operation can be made easily and efficiently. I

A further object of the present invention is to provide an electric razor of a structure wherein blade part and blade driving mechanism are so made as to developa maximum effect or utilizing the space without difficulty within a flat case of a small diameter containing the blade part and blade driving mechanism.

Other objects and advantages of the present invention will become clearer from the following descriptions referred to with reference to accompanying drawings, in which:

FIG. 1 shows in a side view with a part cut out an embodiment of the electric razor according to the present invention.

FIG. 2 is an elevation of the razor shown in FIG. 1 with a part cut out.

FIG. 3 is a side view showing its internal mechanism.

FIG. 4 is a side view showing only the internal mechanism.

FIG. 5 is a perspective view showing the internal mechanism of FIG. 4 as disassembled into parts.

FIG. 6 is a sectioned view of blade part of the razor as taken along VI VI line in FIG. 3.

FIG. 7 is a perspective view of the blade part and blade holder of the razor as disassembled from the razor body and into the respective parts, and

FIG. 8 shows in similar manner with FIG. 4 an arrangement of dry cell supporting member in another embodiment of the present invention.

While the present invention shall be explained with reference to the particular embodiments shown, it should be understood that the intention is not to limit the invention to these embodiments but rather to include all modifications and equivalent arrangements covered by the scope of the appended claims.

In the drawings, 1 is a case of the electric razor and said case 1 is formed so as to be dividable into a cylindrical dry cell case 2 closed at one end and a covering case comprising two

halves

3 and 4 split in parallel to the razor blade surface for covering the blade part and driving mechanism therefor, and one half 4 is formed so as to be further dividable at a part facing the blade part as a blade holder 5. 6 is an entire internal mechanism formed as a block independently of the case 1 (FIG. 4), which comprises a blade driving part 7, motor 8, electric dry cell 9 and electrically conductive cell supporting metal piece 10. The motor 8 is fixed to a frame 11 forming the driving part 7 and to the cell supporting metal piece 10 with screws 12. The dry cell 9 is removably fitted between the motor 8 and an engaging part 13 formed by bending the lower end of the cell supporting metal piece 10. A compression coil spring 14 is inserted between the dry cell 9 and said engaging part 13. Said dry cell 9 is connected at the anode side directly with the motor 8 and at the cathode side with the motor 8 through the compression coil spring 14 and the dry cell supporting metal piece 10.

Referring to the internal mechanism 6 with reference to FIGS. 3 5, the driving part 7 driven by the motor 8 for driving the movable cutter blade comprises various component parts fitted to the frame 11 made of a plastic material, for example, a synthetic resin and fixed to an end of the motor 8, as detailed later. The component parts forming the driving part 7 are preferably formed of such synthetic resin as nylon, Derlin (trade name of a polyacetal resin), molybdenumcontaining nylon, glass fiber-containing nylon or the like. In the structure, as shown in FIG. 3, a worm 17 and a worm wheel 18 meshing with it, having an eccentric cam 19 in the lower part are connected with a motor shaft 16 passed through a bottom plate 15 of the frame 11. The worm wheel 18 is mounted for rotation on a shaft 20 provided to project on the frame 11. The eccentric cam 19 is, as seen in FIG. 5, to fit in a slot 22 provided at the rear end of a reciprocating sliding lever 21 so that, when the wheel 18 is driven and said eccentric cam 19 rotates in the slot 22, said reciprocating sliding lever 21 will reciprocate and slide upward and downward in the drawing with a pin 24 as a guide which is provided to project on the frame 11 and passed through a slot 23 in the reciprocating sliding lever 21. A switch block 25 is disposed in a recess 27 provided in the frame 11. A frame cover 26 is fixed over the frame 11 so that the switch block 25 will be exposed through a notch 27 in the frame cover 26. Two projections 28 provided to project on the frame 1 1 are passed through the frame cover 26 and the cover 26 is fixed to the frame 11 with screws 29.

The internal mechanism 6 assembled as one block in the above manner is to be housed in the case 1 in such manner that the motor 8 and driving part 7 are initially placed in the one half 3 of the covering case and are then covered with the other half 4 of the covering case excluding the blade holder 5, the two

halves

3 and 4 are fixed to each other with a screw 30 substantially at the center of the half 3 (FIGS. 1 and 2), and then the dry cell case 2 is screwed at the open end to threaded ends 31 and 32 (FIG. 2) of the respective covering

halves

3 and 4. In such case,

respective projections

33, 33

formed on both sides of the bottom plate of the frame 11 of the driving part 7 fixed to the motor 8 will simultaneously fit in the notches 34, 34' respectively formed on the inner peripheral surfaces of the two

cover halves

3 and 4 and a bottom plate 35 of the dry cell case 2 will push up the engaging part 13 formed by bending the lower end of the dry cell supporting metal piece 10. Thus the internal mechanism 6 is to be supported at three points of the

projections

33, 33 fitted in the two covering

halves

3 and 4 and the engaging part 13 of the dry cell supporting metal piece 10.

Referring to FIGS. 6 and 7, 36 is a blade part of the electric razor. Said blade part 36 is preliminarily fitted to the blade holder 5 forming the covering case half 4 and the holder 5 is then removably fitted to the inner surface of the tip of the other half 3 of the case 1.

In the blade part 36, a projection 42 having a hole 41 and provided in the middle of a guide plate 40 made of a synthetic resin and projections 43 provided on both side of said projection 42 are passed respectively through a center hole 38 and holes 39 on both sides of a movable blade 37, the movable blade 37 and guide plate 40 are fixed to each other with screws 44. Said guide plate 40 and movable blade 37 are mounted on the inside surface of the blade holder 5 through compression coil springs 46 engaged at one end with projections 45 on the inside surface of the blade holder 5, a central slot 48 of a fixed blade 47 and the central projection 42 of the guide plate 40 are opposed to each other, the fixed blade 47 is mounted on the upper surface (in FIG. 7) of the movable blade 37, so that the projections 43 on both sides of the guide plate 40 will slidably pass respectively through slots 49 on both sides of the fixed blade 47. In this case, both side projections 54, 54' of a notched opening 52 of the blade holder 5 are fitted respectively in notches 53, 53' formed on both sides of the rear part of an exposed edge blade 50 of the fixed blade 47, so that the exposed edge blade 50 of the fixed blade 47 and the blade tip 51 of the movable blade 37 will project out of the notched opening 52 of the holder 5. Then the fixed blade 47 is fixed to screw holes 56 made on the inside surface of the blade holder 5 with screws 55. In fixing the fixed blade 47 to the blade holder 5 with screws 55, a blade holder fixing metal piece 58 having a spring section 57 erected in the form of V is fixed to the fixed blade 47 simultaneously with the screw 55 for fixing the fixed blade at a position adjacent the tip of the blade holder 5. The blade holder 5 fitted with the blade part 36 is removably fitted to the inside surface of the tip of the covering case one half 3, by engaging a projection 60 (FIGS. 1 and 7) formed in the rear part with the lower part of a tip 61 of the covering case one half 4 and engaging the V-shaped spring 57 of the blade holder fixing metal piece 58 fixed to the fixed blade 47 with a projection 62 (FIGS. 2 and 3) formed at the tip of the covering case one half 3. The cross-section in the blade part fitting part is approximately in the form of a horseshoe formed of the covering case half 3 and blade holder 5 as shown in FIG. 6 and, in an inner wide part 63 of said horseshoe formation, a vertical projection 64 formed at the tip of the reciprocating sliding lever 21 is fitted in the hole 41 made in the central projection 42 of the guide plate 40 fixed to the movable blade 37 through the central slot 48 of the fixed blade 47, so that the movable blade 37 will reciprocate and slide as operatively connected with the reciprocating sliding lever 21. A sliding button 65 of the switch block 25 fitted to the internal mechanism 6 slidably projects out of the surface of the covering case half 4 (FIGS. 1 and 2). The cylindrical battery containing section 2 of the casing together with the cylindrically configured part of the two

halves

3,4 of the section threadably connected therewith form a cylindrical gripping portion the axis of which extends in a plane parallel with the sliding direction of the movable blade.

In the internal mechanism 6 shown in FIG. 8, the cell supporting metal piece 10 is prepared in a modified form. That is, the supporting metal piece 10 in this embodiment is divided into two parts 10' and 10 and one part 10' at the motor side is fixed to the bottom plate 15 by the screws 12 and terminated at point 10a substantially adjacent the bottom end of the motor 8, while the other part 10 at the cell side is preferably contained in the cell case 2 so as to extend vertically along inner wall of the case 2 and to be bent at the section 13 along the bottom wall of the case 2 in the similar manner with the arrangement of FIG. 3 or 4. Upper end of the part 10" is terminated at a position 10a" where the same faces the terminating end of the part 10', which position is preferably adjacent the upper open end of the case 2 so that the both ends 10a and 10a" of the two parts 10' and 10" will be depressed for electric contact by means of the open end of the case 2 when the latter is fitted to the

covering case halves

3 and 4. As shown, it is preferable to provide in this case two parallel ends respectively in both the two

parts

10 and 10" so as to ensure the electric connection between the two parts.

The operation of the electric razor according to the present invention is as follows:

When the slidable button of the switch block 25 is slid, the electric connection between the dry cell 9 and the motor 8 is established and the motor is driven. As the motor 8 is driven, the eccentric cam 19 associated integrally with the worm wheel 18 is rotated by the motor through the worm 17 inside the slot 22 of the sliding lever 21. The rotation of the'cam 19 causes the lever 21 to be reciprocally slid in the longitudinal direction of the lever 21 along the pin 24 inserted in the slot 23 of the lever as a guide thereof. This reciprocal sliding movement of the lever 21 is transmitted to the guide plate 40 through the projection 64 at the tip of the lever 21 fitted in the hole 41 of the plate 40, so that the guide plate 40 and the movable blade 37 integrally fixed thereto will be reciprocally slid.

Thus the blade tip 51 of the movable blade 37 is reciprocated while being in contact with the stationary edge blade 50 of the fixed blade 47 so as to enable it to cut the hairs.

As described above, according to the present invention, the assembly and disassembly of the razor are made very easy by the combination of these effects, the structure has few component parts and is simplified and thus a shaving or hair cutting operation can be made easily and efiiciently.

What we claim is:

1. A battery operated electric razor comprising a pair of comb-shaped fixed and movable blades, said movable blade being reciprocally slidable in contact with said fixed blade, a frame member, driving means including a driving lever coupled at one end thereof to said movable blade for reciprocally sliding the same and fixed to one side of said frame member, a motor fixed to the other side of said frame member'for operating said driving means and provided with a rotary shaft extending through said frame member, at least one dry cell battery disposed in contact at one pole thereof with an input terminal of said motor, an electrically conductive metallic member for supporting said dry cell battery secured at one end thereof to said frame member and having the opposite end thereof in contact with the other pole of said battery, and a case enclosing said frame member and the components secured thereto which form an integral internal mechanism independent of the case, said case being constituted by a first cylindrical section closed at one end for housing said battery and threaded at the other open end thereof and a second section comprising two connected together halves divided in the axial direction of the razor, one part of said second section of said case housing said driving means and another part of said section having.

a cylindric configuration housing said motor and terminating in an open threaded end which is screw connected to the threaded open end of said first cylindrical section, said first cylindrical section together with said cylindrically configured part of said second section of said casing establishing a gripping portion having its axis extending in a plane parallel with the sliding direction of said movable blade.

2. An electric razor as defined in claim 1 wherein said frame member is provided with at least one projection, wherein said second section of said case is provided with a complementary notch which fixes said internal mechanism into its proper position within said case and wherein the closed end of said first cylindrical section of said case when screwed into place onto said cylindric part of said second section urges the poles of said battery into engagement respectively with the end of said metallic battery supporting member and said motor input terminal.

3. An electric razor as defined in claim 1 and wherein one of said halves of said second section of said case is divided into two parts such that one part thereof holds said fixed and movable blades and is detachable while holding said blades.

4. An electric razor as defined in claim 1 wherein one of said halves of said second section of said case is divided into two parts at a right angle to the axial direction of the razor such that one part thereof constitutes a detachable holder for said fixed and movable blades, said holder having a projection at the divided-side end for engaging the inside surface of the other part and a resilient projection at the other end for fitting resiliently into the inside wall at the corresponding end of the other half of said second section of said case such that when said holder to which said fixed blade is secured and said movable blade is held slidably between said holder and said fixed blade is mounted on the case said holder will be detachably fixed in position and at the same time said movable blade will be operatively engaged with a projection on the lever member of said driving means.

Claims

1. A battery operated electric razor comprising a pair of combshaped fixed and movable blades, said movable blade being reciprocally slidable in contact with said fixed blade, a frame member, driving means including a driving lever coupled at one end thereof to said movable blade for reciprocally sliding the same and fixed to one side of said frame member, a motor fixed to the other side of said frame member for operating said driving means and provided with a rotary shaft extending through said frame member, at least one dry cell battery disposed in contact at one pole thereof with an input terminal of said motor, an electrically conductive metallic member for supporting said dry cell battery secured at one end thereof to said frame member and having the opposite end thereof in contact with the other pole of said battery, and a case enclosing said frame member and the components secured thereto which form an integral internal mechanism independent of the case, said case being constituted by a first cylindrical section closed at one end for housing said battery and threaded at the other open end thereof and a second section comprising two connected together halves divided in the axial direction of the razor, one part of said second section of said case housing said driving means and another part of said section having a cylindric configuration housing said motor and terminating in an open threaded end which is screw connected to the threaded open end of said first cylindrical section, said first cylindrical section together with said cylindrically configured part of said second section of said casing establishing a gripping portion having its axis extending in a plane parallel with the sliding direction of said movable blade.