US2677884A - Rotary razor shear head - Google Patents

Description

May 11, 1954 R. RICHARD 2,677,884 ROTARY RAZOR SHEAR HEAD Filed Dec. 29, 1948 INVENTOR. Rebel-6 BY rron/var Patented May 11, 1954 2,677,884 ROTARY RAZOR SHEAR HEAD Robert Richard, Morges, Switzerland, assignor to Richard & Ammann S. A.,

Switzerland Application December 29, 1948, Serial No. 67,956

2 Claims.

This invention relates to cutting heads for electric razors, of the type in which a pair of secured. Each of the blades preferably makes an angle of not more than 45 with a plane perpendicular to the axis of rotation of the blade assembly.

The invention reference to the which:

Figure 1 is a sectional elevation of a removable cutting head for an electric rotary razor ac cording to the invention;

Figure 2 is an end view of the cutting head shown in Figure 1, the grid or grating being omitted from one half of the View;

Figure 3 is a diagram showing the blade assembly on a larger scale; and

Figures 4 and 5 are diagrams showing two methods of securing the blades to the supporting spring.

is hereinafter described with accompanying drawings, in

it is to be understood that the invention is ap plicable also to razors in which the cutting head comprises a cap I, the closed. by a domed sheet 2 of very thin bronze (a suitable thickness being 0.05 mm), which sheet is perforated with a large number of small holes to form a grid or grating. The sheet 2 is kept in position and held in tension by a collar 3 fitting within the cap l. Bayonet slots 4 are provided for securing the cap to arazor body.

A spindle 5 carrying a coupling unit 6 for engagement with a complementary coupling unit in the body is mounted in a bearing 1 in the cap, a lubricating bushing 8 being provided in the bearing. The bearing is supported in a spider 9 secured in the cap by a spring ring I 0, which enables the spindle to be easily removed for inspection and maintenance.

The spindle 5 has secured to it by screw threads a support II to which is secured a spring memfrom a fiat resilient plate, the member having two tapering arms I3 and M which form approximately half-helices of opposite hand to one another. To the outer end of as to lie 1n planes making angles of between 20 with a plane perpendicular to the axis of rotation of the blades, the angle depending on the thickness of hair which the razor is intended to cut.

The curvature of the cutting blades l5 and Hi along their cutting edges is tangential to the domed part of the grid 2, so that during rotation, the blades, due to centrifugal force, are pressed against the inside surface of the grid, and they Figures 4 and 5 show two alternative arrangements of the connections between the spring arms l3 and I4, and the blades l5 and I6. In Figure 4, the blade I 5 is welded to a bent-over arm I 3 and thus makes an angle with the said arm, whereas in Figure 5 the blade [6 is welded to the arm M itself, and lies parallel to the said arm.

The spring arms [3 and I4 act to some extent as fan blades and produce a flow of air which assists in cooling the grid 2, to compensate for the heating tendency due to the friction of the blades I5 and IE thereon.

I claim:

1. A rotary shear head for dry shavers, comprising, a casing having means at its lower end for detachably connecting with the bottom of and having means for clamping the grid to said flange, a spider plate having an outer portion backing up the collar and having an inner portion constituting a bearing support, a split spring ring normally seated in the groove to hold the spider, collar and grid assembled within the casing, a bearing fitted in the inner portion of the spider, a shaft mounted in the bearing, a motor coupling at the lower end of the shaft, a blade support detachably fitted to the upper end of the shaft, a pair of shear blades with arcuate cutting edge disposed in opposite directions and bearing against the inner face of the grid, and

helically spaced spring arms having the shear blades mounted on their upper ends and have. ing their lower ends secured to the blade sup,- port.

2. In a rotary shear head for dry shavers, the combination, including, a spherical dished perforated grid forming the outer face of the head, a motor driven rotary support in the head and spaced from the grid, and a unitary resilient cutting unit confined between the grid and the su p.

port, said unit including a plate mounted on thesupport and having helicoidal spring arms integrally connected at their base with diametrically opposite portions of the plate, said arms extending upwardly toward the grid and providing free diametrically opposite terminal portions spaced approximately 90 from the junction of the base of said arms with the plate, and cutting blades. secured to. the said terminal portions of the arms and having arcuate leading cutting edges wiping the inner face of the grid.

lieierences, Cited in the file of this patent UNITED STATES PATENTS

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