US2555621A

US2555621A - Electric shaver or razor

Info

Publication number: US2555621A
Application number: US49714A
Authority: US
Inventors: Benjamin F Williamson; Jacques Alfred W St
Original assignee: WILLIAMSON Co
Current assignee: WILLIAMSON Co
Priority date: 1948-09-17
Filing date: 1948-09-17
Publication date: 1951-06-05
Anticipated expiration: 1968-06-05

Description

June 5, 1951 B. F. WILLIAMSON ET AL 5,62

ELECTRIC SHAVER 0R RAZOR Filed Sept. 17, 1948 I rl/l/l/J 7/4 a Ill/Ill: v u I I l I N V EN TORS. BEA/J/YM/N E WILL/H4450 QLFQED 6 5x JHC'QUES fl TTOEA/E Patented June 5, 1951 UNITED STATES PATENT OFFICE W. St; Jacques, Glendale, Calif.;

said St.

Jacques assignor to said Williamson Application September 17, 1948, Serial No. 49,714

6 Claims.

This invention relates to mechanically actuated shavers or razors. Such razors are usually actuated by an electric motor mounted within the casing of the razor or through the instrumentality of a flexible shaft.

This type of razor has a cutter-head including a cutter that oscillates to and fro behind a perforated concavo-convex guard. As the guard is pressed against the face and advanced, some of the hairs that project through the perforations are shaved off, or cut off. But the action of such a razor is somewhat disappointing, because it is usually necessary to pass and repass the guard over the same areas to obtain a clean shave. This is probably due to the fact that in a certain position, when the blade is passing a certain series of perforations, the hairs between these perforations remain uncut.

One of the objects of this invention is to provide a razor of this type with a cutter-head mounted in such a way that the entire cutterhead as an entity is oscillated, so that when the cutter head is advanced across ones face the guard together with the cutter within it, will be shifted continuously into a number of slightly altered positions. As the cutter is oscillating at a relatively high speed, the result is that if certain hairs are missed on one stroke of the cutter, they will be in a relation to the perforations that will insure their being shaved off on some succeeding stroke of the cutter blade.

Another object of the invention. is to provide a construction that will enable this improvement to be applied to a well-known type of automatic razor without altering its driving means for the cutter, and by making relatively slight alterations in the details of the razor.

Further objects of the invention will appear hereinafter.

The invention consists in the novel parts and combinations of parts to be described hereinafter, all of which contribute to produce an efficient electric shaver or razor.

A preferred embodiment of the invention is described in the following specification, while the broad scope of the invention'is pointed out in the appended claims.

In the drawing Fig. 1 is a vertical section through the cutterhead of an electric shaver or automatic razor, illustrating our improvement applied to the same; this section is taken about in the plane of the line |l of Fig. 2, but is upon a larger scale'than Fig. 2. This view shows the oscillating head in its neutral or mid position; and the body of the razor is broken away.

Fig. 2 is an ideal vertical section passing down through the guard, showing some of the parts in side elevation, and further illustrating details of our improvement.

Fig. 3 is a view similar to Fig. 1 but showing the cutter-head at an extreme point in its oscillation toward the right.

Fig. 4 is a view also similar to Fig. 1 but showing the cutter-head at an extreme point of its oscillation toward the left.

Fig. 5 is a side elevation of the complete razor as projected onto a plane parallel to the medial plane that passes through the axis on which the cutter rocks.

Fig. 6 is a diagrammatic view graphically illustrating how the guard is pressed. against ones cheek in shaving, and includes arrows indicating how the cutter-head is oscillated to and fro automatically as it is moving along the check by ones hand.

Referring more particularly to the parts, the razor to which we have applied our improvement, includes a body I including a casing or housing 2 and motivating means including a motor 3 from which a driving shaft l extends upwardly through a base plate 5.

In this type of razor the drive-shaft 4 carries a rigid driving disc '5 that carries a drive-pin l on its upper side that is located in a plane that is radial to the axis of the shaft, and. inclines toward the shafts axis in an upward direction. This pin fits freely in a slot 8 between two parallel plates 59 that project down from the rockshaft it that swings the cutter blade ii to and fro. This rock-shaft it has its bearings in a bonnet 12 with inclined side walls Ilia and I21) that are united to each other above by an arcuate peak [3.

In the razor to which we have applied our improvement, this bonnet or housing 52 is fixed. Furthermore, its upper side has two deep notches 14 that extend down into it from above, through which the rock-shaft Ill extends.

In each of these notches a rocker arm I5 is secured rigidly to the rock-shaft. These rocker arms extend toward the guard l6 and their ends have slots ll. They carry the back edge of a cutter blade ii, that rests against two collars l5 that slide freely on the rocker arms It. Coil springs 24: on the arms 45 maintain the outer edge of the blade ll pressed gently against the inner face of the guard 56.

In applying our improvement to a razor of this type, we mount the bonnet it so that it can rock to and fro on a transverse axis, that is to sayrwe prefer to provide theends of the bonnet with gudgeons 2| that have their bearings in fixed frame plates 22 that extend up as brackets from the base-plate 5. This transforms the bonnet into an oscillating frame capable of oscillating about the axes of the gudgeons 2| which, of course, are in line with each other.

We provide means for oscillating the bonnet or oscillator frame from the drive-shaft 4. The oscillator frame is preferably oscillated at much lower frequency than the oscillation of the cut ter means. To accomplish this we provide a bracket 23 with cars 24 at its ends that are secured by means such as screws 25 to substantially vertical side walls 26 of the bonnet l2.

This bracket 23 is of substantially triangular form, as illustrated, and its lower angle or end is formed with means to engage a rotary part driven by the drive-shaft 4. For this purpose we prefer to provide a countershaft 2'! with end journals having their bearings in the end brackets or plates 22 already referred to. This countershaft 21 has a cam r eccentric 28 that fits into a slot 29, and of course as the cam rotates on the axis of the countershaft it swings the bonnet l2 alternately toward the right as illustrated in Fig. 3, and toward the left as indicated in Fig. 4. This swinging movement of the rocker-bonnet does not interfere with the driving function of the driving pin 1, that continues its driving movement regardless of the oscillations of the bonnet I2.

The bonnet I2 has integral end walls 30 with arcuate edges 3| that conform to the shape of the guard I6 which is of the usual cylindrical shell form to enable the two cutting edges 13a of the cutter blade I l to sweep along it. The side edges of the guard seat in shouldered notches 30a formed in the side edges of the end plates 30 of the bonnet, and they are held there by side plates 32 that have offset hooks 33 at their upper edges that take hold in slots 34 located near the side edges of the guard l6.

These side-plates 32 have hooks 35 at their lower edges that hook under the lower edges of the side walls 26 of the bonnet [2.

The side-plates 32 are preferably formed with bows 36 that give them resiliency that facilitates the application of the

hooks

33 and 35 when attaching these side plates in position.

In order to drive the countershaft 27 we prefer to employ a reduction gear including a worm 31 keyed to shaft 4 and meshing with a worm-wheel 38 keyed on the countershaft 21. Such a drive connection preferably reduces at approximately 1 to this ratio in the razor to which we have applied our invention would give the cutter-head about twenty oscillations per second about the axis of countershaft 21. In other words, in one second the cutter blade would pass the hairs in a great multiplicity of different positions, making it practically impossible for any hairs to escape the cutter.

This mode of operation is illustrated in Fig. 6

in which the long arrow 39 indicates the advance of the razor by ones hand in passing over the surface 40 of the face. During the period of one second the cutter-head moves forward and back through about twenty short movements as indicated by the'two short'arrows. In practice the amount of this step-by-step movement of the oscillating head need be very slight; a movement of one thirty-second of an inch would probably be sufficient. But in order to disclose the invention more graphically, the amplitude of wobble or 4 oscillation of the cutter-head has been exaggerated in the drawing.

Attention .is called to the nice co-operation between the elements of our invention with this type of driving connection from the drive-shaft to the rock-shaft Ill. Our improvement is particularly adapted for co-operation with a free or slip-connection such as the revolving pin 1 working in the slot 8. Such a free connection permits the shifting movements of the cutter-head without any possibility of causing any binding in the drive connection to the cutter blade, or developing any stresses in the parts employed in this driveconnection.

Attention is also called to the fact that in order to transform an electric shaver of the type described and illustrated, to include our invention, it is not necessary to alter any of the mechanism or working parts that supply the motive power for the cutter blade. It is merely necessary to mount the cutter-head assembly including the guard and cutter blade so that they can be oscillated as a unit or entity; and to lengthen the drive shaft 4 suificiently to provide it with a driving connection for effecting the oscillations of the cutter-head assembly. In practice, the amount of extension required for the drive shaft is very slight. In Fig. 1, however, the proportions have been purposely exaggerated so as to illustrate more clearly the parts of our invention and their relation to the other parts with which they cooperate.

In the operation of this razor the oscillation of the cutter head causes the point of contact of the guard with the cheek to apply slight pressure to the skin, which causes the flesh to depress slightly to conform to the curvature of the shell or guard of the cutter-head. This oscillating movement is of course automatic and occurs continuously in a forward and backward direction with a wiping or brushing effect against ones face. Many times per second these forward and. backward movements occur while the razor is being passed over the face by ones hand. As a result of the co-operation of these two movements the short whiskers are caused to protrude through the perforations in the shell of the head where they are clipped or shaved; This insures a close shave and an eflicient shave, cutting off all of the hairs close to ones skin.

Many other embodiments of the invention may be resorted to without departing from the spirit of the invention.

We claim as our invention:

1. In an electric shaver, the combination of a casing, motivating means carried therein, an oscillator frame mounted for rocking movement in the casing, a guard of shell form supported on the oscillator frame, and curved about an axis on the oscillator frame, a blade behind the guard, supported on the oscillator frame to move to and fro on said axis, a drive-shaft rotatably mounted in the casing, means for actuatingthe blade by the driving shaft, and means for effecting the rock; ing of the oscillator frame by the drive shaft at a lower frequency than that of the cutter means.

2. In an electric shaver, the combination of a casing, motivating means carried thereon, an oscillator frame mounted for rocking movement in the casing, a guard of shell form supported on the oscillator frame, and curved about an axis on the oscillator frame, a blade behind the guard, supported on the oscillator frame to move to and fro on said axis, a drive-shaft rotatably mounted I6 in the casing, means for actuating the blade by the driving shaft, including a reduction gear with a rotary part mounted to rotate about an axis on the casing extending in a plane transverse to the axis on which the oscillator frame rocks and driven by the said driving shaft.

3. An electric shaver according to claim 1, including end members fixed with respect to said casing, and in which the means for effecting the rocking of the oscillator frame includes a camshaft supported on said end members with a cam engaging the oscillator frame at a point removed from its axis of rotation.

4. An electric shaver according to claim 1, including end members fixed with respect to said casing, and in which the means for effecting the rocking of the oscillator frame includes a camshaft supported on said end members and a cam engaging the oscillator frame, at a point removed from its axis of rotation, and a gear connection between the drive-shaft and the cam-shaft for driving the latter.

5. An electric shaver according to claim 1, in which the means for rocking the cutter-means includes a driving pin mounted on the drive shaft with its axis inclined toward the axis of the drive shaft and projecting toward the cutter-means, and means for engaging the pin and actuated thereby to oscillate the cutter about an axis.

6. In an electric shaver, the combination of a casing, motivating means carried therein, an oscillator mounted to rock on the casing, a guard mounted on the oscillator, a cutter blade with means for mounting the same to rock to and fro on an axis on said oscillator, a drive shaft mounted in the casing with its axis substantially in line with the said axis of movement of the cutter, and driven by the motivating means, a free driving connection between the driving shaft and the said cutter blade capable of maintaining the said drive connection regardless of relative shifting of the axis on Which the cutter rocks with respect to the axis of said drive shaft; and means including a driven member actuated by the driveshaft, disposed laterally therefrom, and engaging the oscillator frame for effecting the oscillation of said cutter head from the said drive shaft.

BENJAMIN F. WILLIAMSON. ALFRED W. ST. JACQUES.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS 2,342,467 Hagopian Feb. 22, 1944