US3261091A

US3261091A - Shaving head having concentric cutter elements

Info

Publication number: US3261091A
Application number: US384613A
Authority: US
Inventors: Driest Jan Van Den
Original assignee: US Philips Corp
Current assignee: US Philips Corp; North American Philips Co Inc
Priority date: 1963-08-20
Filing date: 1964-07-23
Publication date: 1966-07-19
Anticipated expiration: 1983-07-19
Also published as: ES303268A1; DE1285917B; FR1406225A; CH439008A; NL296894A; BE651972A; GB1075899A

Description

July 19, 1966 J. VAN DEN DRIEST 3,261,091

SHAVING HEAD HAVING CONGENTRIC CUTTER ELEMENTS Filed July 25, 1964 Inn INVENTOR.

JAN VAN DEN DRIEST AGENT United States Patent C) 3,261,091 SHAVING HEAD HAVING CONCENTRIC CUTTER ELEMENTS Jan van den Driest, Drachten, Netherlands, assignor to North American Philips Company, Inc., New York, N .Y., a corporation of Delaware Filed July 23, 1964, Ser. No. 384,613 Claims priority, application Netherlands, Aug. 20, 1963, 296,894 3 Claims. (Cl. 30-43;.6)

The invention relates to a shaving head for use in a dry shaving apparatus comprising a round shear plate having concentric running grooves for the cutting members in a single plate, co-operating with a cutting head provided with concentric cutter rims united to form an integral part on a single support.

Such constructions have rarely been employed in practice or they have not been used at all, since it did not appear to be possible to obtain such a co-operation between the races and the cutting members to be produced in series without excessive cost that, when the shaving head is pressed against the skin a uniform shaving effect is obtained.

The invention has for its object to provide an improvement in this respect and is characterized in that the thickness of the upright edges of the plate, bounding the laminations, measured along a radial line through said edges, is more than twice the length of the laminations between said edges, while the cutter rims are centered with respect to the plate by direct guiding of the cutter support along an annular face which is located on the inner side with respect to the outer side of the inner cutter rim.

Consequently, in accordance with the invention there is provided a comparatively great thickness of material in a radial sectional area of the portion of the plate where the running grooves are provided, as compared with the width of said running grooves. With a given diameter of the plate the surface of the shaving operation is smaller than is theoretically possible, but the active shaving surface is nevertheless sufiiciently enlarged in this way to justify the complication involved in providing concentric running grooves and concentric cutter rims. In actual manufacture, however, the advantage is obtained that a very small thickness of laminations is permitted with the said ratio between the thickness of the material and the length of the lamination parts bridging the running grooves while the rigidity remains sufficient. Moreover, the upper surface of the plate, as a whole, maintains such a rigidity that the guide of the cutter-rim support, as stated above, can be provided in the inner part of the plate. This provides a simple and accurate guide along an annular path of small diameter, which is of great importance for such a choice of the width of the cutting edges of the cutters with respect to the width of the running grooves that a small clearance will be sufficient, which is conducive to the active shaving surface.

In this case an accurate arrangement of the cutter rims relative to each other and to the axis of rotation is very important and in an advantageous embodiment this is achieved in that the inner cutter rim is welded in the form of a central ring to the bottom of the cup-shaped body of the outer cutter rim while the inner side of the inner cutter rim is guided along the corresponding side of the associated running groove.

In a further embodiment suitable for this purpose a known technique is applied in which separate cutters are arranged in a rim around the axis of rotation of the cutter head formed by a pressure-cast piece and fixed separately in the bottom part thereof, while the cutting edges are located on the head side of the cutter head.

The known cutter heads of this type have a fairly complicated shape, the cutters having for example the form 3251,91 Patented July 19, lgfifi of a T, the long limb of which extends through an opening in the cast piece in downward direction, where it is fixed by separate clamping members, the cutter being at the same time urged laterally against a supporting face.

In accordance with the present invention this construction is such that the walls of the radial grooves are in direct contact with the lower parts of the cutters, the lower edges of which bear throughout their length on the bottom of the groove, while the cast piece supports, in addition, a central, upwardly extending centering pin which fits in a central bore of a shear plate to be arranged over the cutter head.

In this Way the cutters can be rigidly fixed during pressing or casting of the cutter head, while they are held throughout their length both on the two sides and at the lower edges, whereas the ends of the grooves can be left completely open and no downwardly projecting extension is required for fixing the cutters by separate members and to prevent a displacement in the longitudinal direction. In order to allow suitable tolerances in the disposition in the radial direction, for an inexpensive manufacture, without the need for grinding the end edges of the cutters to measure, the centering pin can be formed together with the casting and be directly provided in the central bore of the shear plate. Thus a radial movement of the cutters in the running groove of the shear plate is prevented and a small clearance in the running groove will suflice.

The cut hairs can be readily conducted away to the hair chamber in an advantageous embodiment which is characterized in that the radial grooves are provided in limbs projecting radially from the casting, the upper edges of said limbs extending over part of the bottom surface being bevelled in upward direction towards the grooves.

The invention will now be described with reference to the drawing, while various advantageous aspects thereof will be set forth.

FIG. 1 shows a first embodiment in a vertical sectional view through the axis.

FIG. 2 shows perspectively in a half sectional view a shear plate in a second embodiment and FIG. 3 also shows perspectively the support for the cutter rims, while a cutter removed from the support is shown separately.

Referring to FIG. 1, reference numeral 1 designates the shear plate and 2 designates the support of the cutter rims. It is shown that on the bottom 3 of said support, which has the shape of a cup or dish and with which the outer cutter rim 4 is integral, there is welded a central ring 5, which holds the inner cutter rim 6. The inner side 7 of the cutter rim 6 is guided along the inner side 8 of the corresponding running groove 9.

Viewing a portion of the cutting head indicated by the arrow P, going through the ends of the cutters and the boundaries of the running grooves, it will be apparent that there is supporting material on either side of the laminated parts 10 which bridge the running grooves. The overall width of the two running grooves in a practical embodiment is 3 mms. and the length of the part P is about 8 mms.

In the embodiment shown in FIGS. 2 and 3 the laminated shear plate 11 has two concentric running

grooves

12 and 13, in each of which a cutter rim is adapted to rotate.

The two rows of cutter rims are obtained (see FIG. 3) by fixing a series of cutter plates 14 in a cutter head support 15, each cutter plate having the shape of a U, the ends of the

legs

17 and 18 form the cutting edges, while the ridge or the web 16 is fixed in one of the grooves 19 in support 15.

The upwardly projecting centering pin 21, which is integral with the bottom of the cutter head, is journalled, after mounting, in the central bore 22 of a bearing sleeve 3 23, the latter being housed in the central opening shear plate 11.

The radial grooves 19 are provided in legs radially projecting from the support 15, said legs bearing the reference numeral 24; the upper sides 25 of said legs are projected over a given distance above the top surface 20 of the support 15. On either side of the cutter these sides are bevelled in upward direction, so that the

sloping faces

26 and 27 are formed. The cut hairs can therefore be readily conducted away between the legs 24 towards the hair chamber below the support 15.

From the cutter shown separately in FIG. 3 it will be seen that the Web 16 of each cutter is provided with

openings

28 and 29 so that in the pressure or spray casting process for the cutter head support 15 a material connection is obtained between the sides of the grooves across said openings. The manufacture may be carried out by means of an extrusion process and the casting may consist of so-called sprayed aluminum. The central pin 21 may be made of steel and may be cast at the same time of a sleeve of steel or brass which may he slipped onto an aluminum pin which is integral with the support 15.

In FIG. 3, the broken lines indicate in the separate outter 16 that the legs of the U-shaped cutter may be bent over to one side, so that a sharp cutting angle is obtained after horizontal grinding.

What is claimed is:

1. A shaving head for use in a dry shaver comprising an inverted cup-shaped, apertured shear plate having conof the centric annular grooves therein and a central bore, a 30 rotary cutter support having at least two concentric rings of cutter blades, each of said blades being rotatable in the grooves of said shear plate adjacent to said apertures, the thickness of the lateral walls of the shear plate surrounding said grooves being more than twice the thickness of the portions of the shear plate directly above said grooves, said rotary cutter support being provided with an upwardly projecting centering pin fitted in said central bore, and a plurality of additional grooves extending radially from said rotary cutter support and each adapted to have secured therein at least one of said cutter blades.

2. A shaving head for use with a dry shaver as claimed in claim 1 wherein said cutter blades are U-shaped, with the ends of said legs forming the cutting surfaces.

3. A shaving head for use with a dry shaver as claimed in claim 1 further comprising bevelled side portions adjacent to each of said additional grooves for permitting the cut hair which accumulates thereon to further fall by gravity away from said rotary cutter support.

References Cited by the Examiner UNITED STATES PATENTS 2,119,021 5/1938 Moskovics et a1 30--41.5 2,220,800 11/1940 Jepson 30-354 X 2,238,278 4/1941 Moskovics et al. 30354 X 2,282,539 5/1942 Bahr 3043.6 2,575,741 11/1951 Abrams et al 3034.1 2,616,168 11/1952 Dankers 3043.6 2,632,948 3/1953 Konrad 30-43.6

FOREIGN PATENTS 1,088,648 9/ 1954 France. 571,355 1/1958 Italy.

' WILLIAM FELDMAN, Primary Examiner.

MYRON C. KRUSE, Examiner.

Claims

1. A SHAVING HEAD FOR USE IN A DRY SHAVER COMPRISING AN INVERTED CUP-SHAPED, APERTURED SHEAR PLATE HAVING CONCENTRIC ANNULAR GROOVES THEREIN AND A CENTRAL BORE, A ROTARY CUTTER SUPPORT HAVING AT LEAST TWO CONCENTRIC RINGS OF CUTTER BLADES, EACH OF SAID BLADES BEING ROTATABLE IN THE GROOVES OF SAID SHEAR PLATE ADJACENT TO SAID APERTURES, THE THICKNESS OF THE LATERAL WALLS OF THE SHEAR PLATE SURROUNDING SAID GROOVES BEING MORE THAN TWICE THE THICKNESS OF THE PORTIONS OF THE SHEAR PLATE DIRECTLY ABOVE SAID GROOVES, SAID ROTARY CUTTER SUPPORT BEING PROVIDED WITH