Gear cutting – milling – or planing – Milling – Process
Patent
1989-04-07
1990-11-13
Howell, Daniel W.
Gear cutting, milling, or planing
Milling
Process
51326, B23C 300
Patent
active
049697838
ABSTRACT:
In connection with a Fresnel lens in which concentric pitch base lines are drawn on a curved lens member at certain pitches and a number of radial partitioning lines are drawn so as to pass through the center of the concentric pitch base lines and to cross these lines so that a surface of the lens member is partitioned into a large number of arcuate Fresnel step design sections, and an angled Fresnel step is formed in each of the Fresnel step design sections so that light transmitted from a focal point of the lens at its rear side forms a substantially parallel flux of light through a refractive or reflective prism, the invention relates to the cutting of Fresnel steps in a mold element for forming the lens by causing a tool attached to a multiple axis milling cutter and having an acute point to perform reciprocating or circumferential cutting for every width of each of the inclined surfaces of said Fresnel steps while causing the tool to move radially to perform scan-cutting of the inclined surfaces. The cutting inclination angle at the point of the tool attached on said multiple spindle milling cutter may be made equal to the angle of the Fresnel step at its steep surface side. Alternatively, the tool axis may be varied during cutting to allow the tool angle to correspond to the given angle or angles of the inclined surfaces.
REFERENCES:
patent: 2831394 (1973-07-01), Heenan et al.
patent: 2890627 (1959-06-01), Onksen et al.
patent: 3267279 (1966-08-01), Doolittle
patent: 3744117 (1958-04-01), Heenan et al.
patent: 4149304 (1979-04-01), Brynjegard
patent: 4198182 (1980-04-01), Green
Igarashi Seiji
Kojima Noboru
Nagakura Akira
Ozawa Yasuo
Sakakibara Koichi
Howell Daniel W.
Koito Manufacturing Co. Ltd.
LandOfFree
Method of working fresnel step does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Method of working fresnel step, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method of working fresnel step will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-773460