Abstract The invention relates to gear drives. The globoid worm gearing comprises a cylindrical worm-wheel in mesh with a globoid worm. The side surfaces of the thread of said globoid worm are shaped so as to envelop the side surfaces of the worm-wheel teeth with the result that in the process of successive engagement of the worm thread with the worm-wheel teeth the worm thread makes a linear contact throughout the side surface of the worm-wheel teeth. Said globoidal gearing is capable of transmitting larger torques and possesses a greater kinematic accuracy than like-size modified globoid worm gears known in the prior art. A method of making the globoid worm is provided whereby the worm is generated through relative movements of the worm blank and a rotary cutter and thereafter the side surfaces of the worm thread are finished by honing. The cutting edges of the rotary cutter are located on a generating surface having the shape of the side surfaces of the cylindrical worm-wheel teeth. The finishing is effected by means of a hone with teeth whose side surfaces are identical with the side surfaces of the cylindrical worm-wheel teeth.
A globoid worm gearing comprising: a cylindrical worm-wheel having a plurality of teeth with side surfaces, a globoid worm having a thread with side surfaces and a throat, the side surfaces of the thread of said globoid worm shaped to envelop the side surfaces of the teeth of said cylindrical worm-wheel, means for meshing said worm-wheel with said globoid worm and for engaging the thread of said globoid worm with the teeth of said cylindrical worm-wheel such that said worm thread makes a linear contact throughout the entire side surface of said worm-wheel teeth wherein the contact surface of the globoid worm gearing comprises the contact surface of the cylindrical worm-wheel; the contact lines of the cylindrical worm-wheel envelop the entire side surface of the worm-wheel teeth, while the contact lines of the globoid worm gearing occupy only the medium portion of the tooth side surface, said contact lines on the worm-wheel teeth intersect on the side surface of the working wheel teeth during successive engagement of the globoid worm thread with the teeth of the cylindrical worm-wheel.
Claim 2
Dependent Claim
178 words
A globoid worm gearing comprising: a cylindrical worm-wheel having a plurality of teeth with side surfaces, a globoid worm having a thread with side surfaces and a throat, the side surfaces of the thread of said globoid worm shaped to envelop the side surfaces of the teeth of said cylindrical worm-wheel, means for meshing said worm-wheel with said globoid worm and for engaging the thread of said globoid worm with the teeth of said cylindrical worm-wheel such that said worm thread makes a linear contact throughout the entire side surface of said worm-wheel teeth wherein the contact surface of the globoid worm gearing comprises the contact surface of the cylindrical worm-wheel; the contact lines of the cylindrical worm-wheel envelop the entire side surface of the worm-wheel teeth, while the contact lines of the globoid worm gearing occupy only the medium portion of the tooth side surface, said contact lines on the worm-wheel teeth intersect on the side surface of the working wheel teeth during successive engagement of the globoid worm thread with the teeth of the cylindrical worm-wheel.
Claim 3
Dependent Claim
37 words
A globoid worm gearing as claimed in claim 1, in which the facewidth of the teeth of said cylindrical wormwheel is substantially equal to the root diameter of the thread at the throat of the globoid worm.
Claim 4
Dependent Claim
29 words
A globoid worm gearing as claimed in claim 1, wherein said cylindrical worm-wheel teeth side surfaces are concave in the direction of the thread helix of said globoid worm.
Claim 5
Dependent Claim
56 words
A globoid worm gearing as claimed in claim 1, wherein the said globoid worm thread has a height which gradually diminishes from the throat of the worm to the ends of the worm, and has a thickness between its side edges which gradually diminishes from the throat of the worm to the ends of the worm.