Gear cutting – milling – or planing – Gear cutting – Gear tooth shape generating
Reexamination Certificate
1999-03-17
2001-05-08
Briggs, William (Department: 3722)
Gear cutting, milling, or planing
Gear cutting
Gear tooth shape generating
C409S025000, C409S038000, C409S041000, C409S050000, C409S051000, C451S047000, C451S147000
Reexamination Certificate
active
06227775
ABSTRACT:
FIELD OF THE INVENTION
The present invention generally relates to the internal gears and splines and more particularly also relates to the manufacture of internal gears and splines, i.e. gears and splines having a central toothed bore.
BACKGROUND OF THE INVENTION
In the past, internal gears and splines have been predominantly manufactured with two cutting methods: broaching and shaping.
Broaching involves the use of a broach, an elongated cutting tool having a series of cutting surfaces of increasing size. The broach is passed through the gear bore with the first cutting surface engaging the bore of the blank and thereby removing a small amount of material. With the passage of each successive cutting surface, with their increasing sizes, the length of the gear or spline teeth being made increases. Typically, when the broach passes completely through the bore, the gear or spline has been cut.
Shaping is a process which involves using a shaper-cutter tool which resembles, in appearance, a gear and a machine to manipulate this shaper-cutter tool. Shaping uses a reciprocating motion to cut. For every stroke of a cutter ram, the shaper-cutter tool travels through the bore, taking a slight cut. It then retracts from the edge of the bore and returns to the top of the stroke cycle and repositions itself for the next cutting stroke. This process is repeated until the desired tooth size is reached.
While both broaching and shaping have been successfully used to cut internal gears and splines in the past, they each have drawbacks. Broaches are typically quite expensive. They are often custom built to meet the peculiar needs of a particular gear- and spline-cutting job. They require frequent sharpening and have a limited useful life. Shaping cutters also require frequent sharpening and are relatively slow cutting, owing to the fact that they cut only during portions of one stroke. Because of this, they are actually cutting less than 50 percent of the time they are in operation.
Consequently, there exists a need for improved methods and apparatuses for manufacturing internal gears and splines.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide an economical approach to cutting internal gears and splines.
It is a feature of the present invention to include a milling apparatus for internal gear and spline cutting.
It is an advantage of the present invention to use a relatively inexpensive cutting tool surface.
It is another advantage of the present invention to allow for an increased duty cycle during which cutting actually occurs.
It is another object of the present invention to provide a versatile approach to cutting internal gears and splines.
It is another feature of the present invention to provide an adjustable milling apparatus.
It is another advantage of the present invention to provide a relatively easy approach to vary the size, shape, spacing and number of teeth in an internal gear or spline.
The present invention is a method and apparatus for cutting internal gears and splines which is designed to satisfy the aforementioned needs, produce the previously stated objects, include the above-listed features, and achieve the already articulated advantages.
Accordingly, the present invention is a milling apparatus where the cutting surface is disposed inside the bore of an internal gear or spline. The present invention is also a method of manufacturing internal gears and splines using such a milling apparatus and an internal gear or spline manufactured with such method using such milling apparatus.
REFERENCES:
patent: 1963753 (1934-06-01), Merz
patent: 2665612 (1954-01-01), Nübling
patent: 3570367 (1971-03-01), Looman et al.
patent: 3673660 (1972-07-01), Osplack et al.
patent: 3916569 (1975-11-01), Wydler et al.
patent: 3931754 (1976-01-01), Nishijima et al.
patent: 4058938 (1977-11-01), Härle et al.
patent: 4066001 (1978-01-01), Nishijima et al.
patent: 4083152 (1978-04-01), Lorenz
patent: 4130967 (1978-12-01), Easton et al.
patent: 4534684 (1985-08-01), Johnson
patent: 4543020 (1985-09-01), Shtipelman
patent: 4735019 (1988-04-01), Wiederkehr
patent: 4798504 (1989-01-01), Erwin et al.
patent: 2630406 (1977-02-01), None
patent: 961875 (1982-09-01), None
Briggs William
Simmons Perrine Albright & Ellwood PLC
LandOfFree
Internal gears and splines and milling method and apparatus... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Internal gears and splines and milling method and apparatus..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Internal gears and splines and milling method and apparatus... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2495721