Epicyclic gear exercise device
View Patent ↗An improved elliptical path exercise machine is provided that is simple and robust in its construction, requires minimal maintenance, provides smooth even exercise motion, and which has a compact foot-print. The apparatus includes a pair of planetary gears, sun/ring gears and at least one crank. The crank is supported and arranged so as to be rotatable about a crank axis. Each planetary gear is pivotably secured to the crank about a pivot point located and arranged such that as the crank is rotated the planetary gears engage and rotate relative to their corresponding sun/ring gears while simultaneously revolving about the crank axis so as to form right and left epicylic gear trains. Two foot pedals are each pivotably secured to a corresponding one of the planetary gears and are sized and arranged to support the feet of a user. The layout and geometries of the device are such that each foot-pedal follows a substantially elliptical foot-path as the crank is rotated. The major axis of the elliptical foot-path is greater than twice the effective crank-arm length of the crank so that a compact foot print is attained.
1. An exercise apparatus comprising:
a support frame and a ring gear supported by said support frame, said ring gear comprising an effective working diameter and being generally fixed relative to said support frame;
a crank supported for rotation about a crank axis relative to said support frame, said crank comprising an effective crank-arm length;
a planetary gear positioned within and engaged with said ring gear, said planetary gear being rotationally connected to said crank about a planetary gear axis and comprising an effective working diameter, said planetary gear axis being generally parallel to and offset from said crank axis;
a foot-pedal rotationally connected to said planetary gear, whereby said foot-pedal follows a substantially elliptical foot-path as pedal circulates about said planetary gear axis and said crank rotates about said crank axis; and
said effective working diameter of said planetary gear being equal to one-half said effective working diameter of said ring gear.
2. An exercise apparatus comprising:
a support frame and a ring gear supported by said support frame, said ring gear comprising an effective working diameter and being generally fixed relative to said support frame;
a crank supported for rotation about a crank axis relative to said support frame, said crank comprising an effective crank-arm length;
a planetary gear positioned within and engaged with said ring gear, said planetary gear being rotationally connected to said crank about a planetary gear axis and comprising an effective working diameter, said planetary gear axis being generally parallel to and offset from said crank axis;
a foot-pedal rotationally connected to said planetary gear, whereby said foot-pedal follows a substantially elliptical foot-path as pedal circulates about said planetary gear axis and said crank rotates about said crank axis; and
the number of teeth formed on said planetary gear is equal to one-half the number of teeth formed on said ring gear.
3. An exercise apparatus comprising:
a support frame and a ring gear supported by said support frame, said ring gear comprising an effective working diameter and being generally fixed relative to said support frame;
a crank supported for rotation about a crank axis relative to said support frame, said crank comprising an effective crank-arm length;
a planetary gear positioned within and engaged with said ring gear, said planetary gear being rotationally connected to said crank about a planetary gear axis and comprising an effective working diameter, said planetary gear axis being generally parallel to and offset from said crank axis;
a foot-pedal rotationally connected to said planetary gear, whereby said foot-pedal follows a substantially elliptical foot-path as pedal circulates about said planetary gear axis and said crank rotates about said crank axis; and
said effective working diameter of said planetary gear being equal to about twice said effective crank-arm length of said crank.
4. An exercise apparatus comprising:
a support frame and a ring gear supported by said support frame, said ring gear comprising an effective working diameter and being generally fixed relative to said support frame;
a crank supported for rotation about a crank axis relative to said support frame, said crank comprising an effective crank-arm length;
a planetary gear positioned within and engaged with said ring gear, said planetary gear being rotationally connected to said crank about a planetary gear axis and comprising an effective working diameter, said planetary gear axis being generally parallel to and offset from said crank axis:
a foot-pedal rotationally connected to said planetary gear, whereby said foot-pedal follows a substantially elliptical foot-path as pedal circulates about said planetary gear axis and said crank rotates about said crank axis;
a major axis of said elliptical foot-path being greater than twice said effective crank-arm length; and
said major axis of said elliptical foot-path being about quadruple said effective crank-arm length.
5. An elliptical foot-path exercise apparatus comprising:
a support frame;
a crank rotatable relative to said support frame about a crank axis, said crank having an effective crank-arm length;
a foot pedal in mechanical communication with said crank, said foot pedal being sized and arranged relative to said crank so as to follow a substantially elliptical foot-path relative to said support frame and a major axis of said substantially elliptical foot-path being greater than twice said effective crank-arm length;
a planetary gear mechanically coupling said crank to said foot pedal, said planetary gear comprising an effective working diameter and being sized and arranged to engage a sun/ring gear so as to form an epicyclic gear train, and said sun/ring gear comprising an effective working diameter; and
said effective working diameter of said planetary gear being equal to one-half said effective working diameter of said sun/ring gear.