US2875519A

US2875519A - Hair clipper having shear blade with teeth of uniform width except two marginal teeth of increased width encompassing amplitude of reciprocal blade vibration

Info

Publication number: US2875519A
Application number: US527500A
Authority: US
Inventors: Matthew G Andis
Original assignee: Andis Clipper Co
Current assignee: Andis Clipper Co
Priority date: 1955-08-10
Filing date: 1955-08-10
Publication date: 1959-03-03
Anticipated expiration: 1976-03-03

Description

March 3, 1959 ANDls 2,875,519

HAIR CLIPPER HAVING SHEAR BLADE WITH TEETH OF UNIFORM WIDTH EXCEPT TWO MARGINAL TEETH 0F INCREASED WIDTH ENCOMPASSING AMPLITUDE OF RECIPROCAL BLADE VIBRATION Filed Aug. 10, 1955 ENTOWL MA rn/Ew 6-. /va/s ATTo it 5Y5 United statcS Patent MARGINAL TEETH 0F INCREASED WIDTH t ENCOMPASSING AMPLITUDE OF RECIPROCAL BLADE VIBRATION a Matthew G. Andis, Racine, Wis, asslgnor m .Audls Chpper Co Racine, Wis., a corporation of Wisconsin Application August 10, 1955, Serial No. 527,500 3 Claims. (Cl. 30-210) This invention relates to an outlining hair clipper.

The clipper here involved has small blades with extremely fine teeth adapted to cut the hair so close to the skin as to give substantially the result of shaving. The device is used in lieu of shaving to provide a sharply defined outline for that portion of the hair which remains visible on the head.

From the standpoint of the blades involved, it becomes necessary to provide a fixed blade which tapers to become extremely thin at its toothed end, and one in which all the teeth are fine, even including the terminal teeth at the side margins of the blade which are ordinarily made very heavy. Moreover, these terminal teeth have to taper in a particular manner toward their apices in order to allow the close approach to the ears and other physical features of the patients head and to the hairline. There is, moreover, a more or less critical relationship between the dimensions of the terminal teeth of the fixed blade and the stroke of the movable blade as determined by the clipper motor, whatever its nature.

In the drawings:

Fig. 1 is a diagrammatic plan view of a clipper embodying the invention and having its blade powered by a vibratory motor.

Fig. 2 is a plane view of one of the blades on an enlarged scale.

Fig. 3 is a side elevation of the blade shown in Fig. 2. Fig. 4 is a fragmentary plan view of the end of the clipper showing the movable blade superimposed on the shear blade, the amplitude of vibration being indicated in dotted lines.

It will be understood that the vibratory type motor diagrammatically illustrated in Fig. 1 is purely by way of exemplification since it is broadly immaterial what kind of motor is used. In the type of motor illustrated, the armature 5 has a relatively fixed mounting at 6 and has an integral arm 7 at its end connected to the movable blade 8 which reciprocates respecting a fixed blade or comb plate 9 in a generally conventional manner. The frequency of vibration of the spring arm which provides the armature 5 is mechanically adjusted to enable it to vibrate in synchronism with frequency of the alternating currents supplied to the magnets 10, to and from the poles 11 of which the armature 5 vibrates.

In this type of motor, the amplitude of the armature of vibration is also determined by its design, including its length and thickness and the nature of material from which it is made. In practice, the armature bar is cut from cold rolled stock A; inch in thickness, or thereabouts. It is swedged down to a thickness of .080. If too thick, the armature will be unduly stiff. If too thin, it will not be still? enough and will hang on the poles 11. The manufacturing process is such as to coordinate the amplitude of vibratory movement with the blade teeth dimensions, the teeth being so minute that each intertooth space is completely cleared in each vibration of the movable blade, the over-all amplitude being 'such that despite the narrow marginal teeth of the fixed blade or shear plate, the movable blade doesnot ride beyond the marginal teeth. The thicker the metal of the armature, the shorter will be the amplitude of its vibration but either excessive thickness or excessive thinnesswill result in lossof power. In Fig. 4 the extremes of movable blade positions are indicated by dotted lines and the bracket 25 shows the amplitude of vibration. f The

side margins

12 and 13 of the fixed blade or comb plate 9 are desirably parallel, or approximately so, at the rear of the blade. At 14 and 15 the margins deviate from parallelism by about four degrees at each edge of the blade. Nevertheless, the

portions

14 and 15 continue rectilinearly convergent until they reach a point quite close to the terminal teeth 16 and 17. These teeth must be relatively wider and stronger than the intermediate teeth 18. Nevertheless, for the desired purpose, they must not interfere with use of the clipper in immediate proximity to the ears or nose or other features of the customer. Accordingly, the sidemargins of the blades are arcuately rounded at 19 on a A inch. radius and at 20 they are more sharply rounded on a 3/ inch radius tangent to the tip of the blade.

This leaves each of the teeth 16 and 17 relatively wide at its base but only slightly wider at its tip than the uniform width of the intervening teeth 18 which extend along the outer margin of the blade.

The cross section of the blade 9 from its base to its toothed edge is such as to provide a bearing surface at 22 near the base of the blade and a bearing surface 23 which includes the upper surfaces of the teeth. Between the

bearing surfaces

22 and 23, which are desirably parallel and may be in the same plane, there is an intermediate ofiset portion 24 in which the blade, as a whole, is progressively decreased in thickness from the bearing area 22 toward the bearing area 23 where the thickness is again somewhat increased. However, toward the tips of the

teeth

16, 17, 18, the taper in thickness continues until the finished blade has a thickness at the tips of the teeth which amounts approximately to .014 inch.

The width of the terminal teeth 16, 17 of the stationary blade or shear blade 9 is so determined with reference to the terminal teeth of the movable blade of the amplitude of the stroke of the movable blade that the movable blade will not materially project beyond blade 9 in the course of its reciprocation. Yet the teeth 18 are so fine on both blades that each tooth will, in the course of each reciprocation, move completely across an inter-tooth notch of the associated blade, whereby each inter-toothed space or notch is cleared completely in the course of blade movement, thus giving a clean shearing cut and enabling cut hair to be discharged. by the teeth.

I claim:

1. An outlining hair clipper comprising fixed and coacting movable blades having fine teeth, the movable blade being slightly narrower than the fixed. blade, means supporting the fixed blade, means including a motor for reciprocating the movable blade in a range of reciprocation having an amplitude just sufficient to effect clearance of inter-tooth spaces of the respective blades in the course of reciprocation and insufiicient to project the movable blade beyond the lateral margins of the fixed blade, the fixed blade having marginal teeth wider than the said fine teeth intermediate said marginal teeth, a side tooth of the movable blade overlying one of the marginal teeth of the fixed blade in all positions of the movable blade within said range.

2. The device of claim 1 in which the fixed blade has side margins which, at intermediate points in the side of the blade are slightly convergent, the convergence A aeraaw g I,

w 3 increasing upona radius "at-each side of the blade toward the tips of thesaid marginal teeth of thefixed-blade.

3. A hair clipper blade having a base portion of uniform thickness and a margin remote from said base portion having uniform intermediate teeth and terminal teeth slightly =wi'der'than said intermediate teeth, the sev- -eral-teet-h having -a-commonbearing surface at one face toothed mai'gin of the blade vvhere such side margins are formed on a radius of approximately 7 of an inch,

convergence of the side margins at the terminal teeth of the blade having a radius of approximately /5 of an inch ending at the tips of such terminal teeth.

References Citedinthe-file of this patent 'UNITED STATES PATENTS 757,429 Arc e Apr. 19, 1 904 1,487,189 -Wahl .Mar. 18, 1-924 1,596,908 Wahl a Aug. 124, 1926 2,013,229 Andis Sept. 3, 1935 2,182,597 'Oster Dec. 51 1939 2,704,887

Andis Mar. '29, 1955 ii-NJ