# US 5,330,407 A · Exercise method and apparatus utilizing elastomeric spheres > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 5,330,407 A - Document ID: US5330407A - Status: Granted - Kind: A - Application number: 07/699,771 - Filed: 1991-08-19 - Granted: 1994-07-19 - Earliest claimed: 1991-08-19 - Assignees: Spherepoint, Inc. - Inventors: Mark J. Skinner - Web page: https://patentgrep.com/patent/US5330407A ## CPC - A63B 21/012: using frictional force-resisters {(electromagnetically-controlled brakes A63B21/0056)} - A63B 21/00069: {Setting or adjusting the resistance level; Compensating for a preload prior to use, e.g. changing length of resistance or adjusting a valve} - A63B: APPARATUS FOR PHYSICAL TRAINING, GYMNASTICS, SWIMMING, CLIMBING, OR FENCING; BALL GAMES; TRAINING EQUIPMENT (apparatus for passive exercising, massage A61H) ## Abstract A controlled mechanical friction principle is disclosed utilizing elastomeric spheres. The spheres are grouped in radial or nested formation between at least two working surfaces and contained in such a manner that compression sliding friction occurs between spheres. A frictional resistance adjustment is provided by means controlling the degree to which the elastomeric spheres are compressed. A walled container has pliable balls arranged as a single covering therein against a back surface, and an opposing piston is structured to move freely within the container walls. The degree of adjustable contact made by the cylinder inner wall surfaces against the spheres regulates the applied frictional resistance. Variable degrees of power transfer or brakeage is developed between the container inner surface wall and the opposing cylinder inner surface wall with the compressed spheres as the passage medium. ## Claims ### Claim 1 A variable friction device comprising, in combination: a first member having a first engaging surface, a second member having a second engaging surface, said first and second engaging surfaces of said first and second members spaced apart, at least one of said first and second members being a sphere with the engaging surface of said one member being spherical, at least one elastomeric sphere located between said first and second members and in contact with said first and second engaging surfaces, and means for moving one of said engaging surfaces or said elastomeric sphere relative to at least one of said first and second member, said at least one elastomeric sphere including a plurality of a elastomeric spheres located between said first and second members, each of said spheres in contact with both of said first and second engaging surfaces and with at least one other sphere and wherein said moving means moves said elastomeric sphere and said means for moving said elastomeric sphere causes the surfaces of said spheres to move with respect to said first and second surfaces and produces sliding friction between at least a pair of said spheres in contact with one another. ### Claim 2 A variable friction device comprising, in combination: a first member having a first engaging surface, a second member having a second engaging surface, said first and second engaging surfaces of said first and second members spaced apart, at least one of said first and second members being a sphere with the engaging surface of said one member being spherical, a plurality of elastomeric spheres located between said first and second members, means laterally of at least one of said first and said second engaging surfaces for confining said spheres in the space between said first and second engaging surfaces, each of said spheres in contact with both of said first and second engaging surfaces and with at least one other sphere, means for moving one of said engaging surfaces or said spheres relative to one of said laterally confining means, said first engaging surface and said second engaging surface to produce sliding friction between at least a pair of said spheres in contact with one another. ### Claim 3 (depends on 2) The device of claim 2 wherein at least one of said first and second surfaces is at least hemispherical. ### Claim 4 A variable friction device comprising, in combination: a first member having a first engaging surface, a second member having a second engaging surface, said first and second engaging surfaces of said first and second members spaced apart, at least one of said first and second members being a sphere with the engaging surface of said one member being spherical, a plurality of elastomeric spheres located between said first and second members, means laterally of at least one of said first and said second engaging surfaces for confining said spheres in the space between said first and second engaging surfaces, each of said spheres in contact with both of said first and second engaging surfaces and with at least one other sphere, means for moving one of said engaging surfaces or said spheres relative to one of said laterally confining means, said first engaging surface and said second engaging surface to produce sliding friction between at least a pair of said spheres in contact with one another and means for moving said first and second members relative to one another in the direction of the shortest distance between said first and second services of said first and second members to change the compression on said spheres by said first and second members. ### Claim 5 A variable friction device comprising, in combination: a first member having a first engaging surface, a second member having a second engaging surface, said first and second engaging surfaces of said first and second members spaced apart, at least one of said first and second members being a sphere with the engaging surface of said one member being spherical, a plurality of elastomeric spheres located between said first and second members, means laterally of at least one of said first and said second engaging surfaces for confining said spheres in the space between said first and second engaging surfaces, each of said spheres in contact with both of said first and second engaging surfaces and with at least one other sphere, means for moving one of said engaging surfaces or said spheres relative to one of said laterally confining means, said first engaging surface and said second engaging surface to produce sliding friction between at least a pair of said spheres in contact with one another and said moving means moving said elastomeric spheres, said means for moving said elastomeric spheres including means for moving one of said first and second engaging surfaces at the point of contact of said one of said first and second engaging surfaces with at least one of said elastomeric spheres in a direction parallel to the plane of the other of said engaging surfaces at the point of contact of said engaging surface with said one elastomeric sphere. ### Claim 6 A variable friction device comprising, in combination: a first member having a first engaging surface, a second member having a second engaging surface, said first and second engaging surfaces of said first and second members spaced apart, at least one of said first and second members being a sphere with the engaging surface of said one member being spherical, a plurality of elastomeric spheres located between said first and second members, means laterally of at least one of said first and said second engaging surfaces for confining said spheres in the space between said first and second engaging surfaces, each of said spheres in contact with both of said first and second engaging surfaces and with at least one other sphere, means for moving one of said engaging surfaces or said spheres relative to one of said laterally confining means, said first engaging surface and said second engaging surface to produce sliding friction between at least a pair of said spheres in contact with one another and said moving means moving said elastomeric spheres, said means for moving said elastomeric spheres including means for moving at least one of said first and second engaging services relative to said lateral confining means. ### Claim 7 A variable friction device comprising, in combination: a first member having a first engaging surface, a second member having a second engaging surface, said first and second engaging surfaces of said first and second members spaced apart, at least one of said first and second members being a sphere with the engaging surface of said one member being spherical, a plurality of elastomeric spheres located between said first and second members, means laterally of at least one of said first and said second engaging surfaces for confining said spheres in the space between said first and second engaging surfaces, each of said spheres in contact with both of said first and second engaging surfaces and with at least one other sphere, means for moving one of said engaging surfaces or said spheres relative to one of said laterally confining means, said first engaging surface and said second engaging surface to produce sliding friction between at least a pair of said spheres in contact with one another, said means for moving said elastomeric spheres including means for removing both of said first and second surfaces relative to said lateral confining means. ### Claim 8 (depends on 2) The device of claim 2 including at least three elastomeric spheres having their diameters substantially aligned together and normal to said lateral confining means.