# US 7,744,509 B1 · Reinforcement member to enhance rotational motion such as for use in a stilt device > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 7,744,509 B1 - Document ID: US7744509B1 - Status: Granted - Kind: B1 - Application number: 11/361,241 - Filed: 2006-02-24 - Granted: 2010-06-29 - Earliest claimed: 2006-02-24 - Assignees: Emmert Second Limited Partnership - Inventors: Raymond L. Emmert - Web page: https://patentgrep.com/patent/US7744509B1 ## CPC - A63B 25/00: Stilts or the like - A63B 21/023: {Wound springs} - A63B: APPARATUS FOR PHYSICAL TRAINING, GYMNASTICS, SWIMMING, CLIMBING, OR FENCING; BALL GAMES; TRAINING EQUIPMENT (apparatus for passive exercising, massage A61H) ## Abstract Apparatus for enhancing relative rotation between a substrate and a rotatable member. The substrate preferably comprises a pole of a leg support assembly in a stilt device, and the rotatable member preferably comprises a leg engagement assembly of the stilt device which engages a user's leg. The reinforcement member preferably operates as a spacer for the substrate, as well as to reduce wear between the substrate and an elongated member which couples the rotatable member to the substrate. A limit surface of the reinforcement member limits mechanical deflection of the elongated member and preferably comprises an annular sidewall of an aperture. A locking feature of the reinforcement member preferably comprises a tab which engages a channel in the substrate to maintain a desired axial orientation of the reinforcement member. ## Claims ### Claim 1 An apparatus comprising: a substrate comprising a wall surface with an annular sidewall of a first aperture that extends through the substrate and has a first overall diameter; a rotatable member adjacent the substrate; an elongated member comprising a sidewall which extends adjacent the wall surface to form a first gap therebetween, the elongated member facilitating relative rotation between the substrate and the rotatable member about a central axis along which the elongated member is nominally aligned; and a reinforcement member comprising: a limit surface which comprises an annular sidewall of a second aperture that extends through the reinforcement member and has a second overall diameter less than the first overall diameter, the limit surface extending adjacent the sidewall of the elongated member to form a second gap therebetween, the limit surface configured to reduce mechanical contact between the sidewall of the elongated member and the wall surface of the substrate as a result of mechanical deflection of the elongated member away from the central axis and toward the wall surface during said relative rotation; and a locking feature which engages the substrate to substantially prevent axial displacement of the reinforcement member relative to the substrate so that the wall surface and the limit surface are substantially maintained in a fixed relationship with respect to the central axis; wherein the substrate is characterized as a pole, wherein the reinforcement member is characterized as a spacer sized to nest within said pole, and wherein the elongated member successively and concurrently extends through a first side of the pole, through a first side of the reinforcement member, through a second opposing side of the reinforcement member, and through a second opposing side of the pole. ### Claim 2 (depends on 1) The apparatus of claim 1, wherein the wall surface of the substrate comprises an annular sidewall of an aperture that extends through the substrate. ### Claim 3 (depends on 2) The apparatus of claim 2, wherein the aperture is characterized as a first aperture, and wherein the limit surface of the reinforcement member comprises an annular sidewall of a second aperture that extends through the reinforcement member. ### Claim 4 (depends on 3) The apparatus of claim 3, wherein the first aperture has a first diameter, and wherein the second aperture has a second diameter less than the first diameter. ### Claim 5 (depends on 1) The apparatus of claim 1, wherein the elongated member comprises a threaded fastener which engages the substrate and the rotatable member to apply a compressive force thereto. ### Claim 6 (depends on 1) The apparatus of claim 1, wherein the rotatable member comprises a leg attachment assembly configured to engage a leg of a user. ### Claim 7 (depends on 1) The apparatus of claim 1, wherein the reinforcement member comprises a cap portion configured to engage a second wall of the substrate, a body which depends from the cap portion, and a collar portion which extends from the body. ### Claim 8 (depends on 7) The apparatus of claim 7, wherein the limit surface comprises an annular sidewall of an aperture which extends through the collar portion, and wherein the locking feature comprises a tab which extends from the body. ### Claim 9 An apparatus comprising: a reinforcement member configured to reduce mechanical wear between a substrate and an elongated member, the reinforcement member comprising: a limit surface which extends adjacent a sidewall of the elongated member to form a gap therebetween, the limit surface configured to reduce mechanical contact between the sidewall of the elongated member and a first wall surface of the substrate as a result of mechanical deflection of the elongated member away from a central axis and toward the wall surface; a cap portion configured to engage a second wall surface of the substrate, a body which depends from the cap portion, and a collar portion which extends from the body; and a locking feature which engages the substrate to substantially prevent axial displacement of the reinforcement member relative to the substrate so that the wall surface and the limit surface are substantially maintained in a fixed relationship with respect to the central axis, wherein the wall surface of the substrate comprises an annular sidewall of a first aperture that extends through the substrate and has a first overall diameter, wherein the limit surface of the reinforcement member comprises an annular sidewall of a second aperture that extends through the reinforcement member and has a second overall diameter less than the first overall diameter, and wherein the elongated member concurrently extends through the first and second apertures. ### Claim 10 (depends on 9) The apparatus of claim 9, wherein the limit surface of the reinforcement member comprises an annular sidewall of an aperture which extends through the collar portion, wherein the elongated member extends through said aperture. ### Claim 11 (depends on 9) The apparatus of claim 9, wherein the body is characterized as annular and configured to nest within the substrate. ### Claim 12 (depends on 9) The apparatus of claim 9, wherein the reinforcement member further comprises a second collar portion comprising a second aperture with an annular sidewall configured as a second limit surface, wherein the elongated member further extends through said second aperture. ### Claim 13 (depends on 9) The apparatus of claim 9, wherein the reinforcement member further comprises a spacer surface that engages the substrate to resist a compressive force applied to the substrate by the elongated member. ### Claim 14 (depends on 9) The apparatus of claim 9, wherein the locking feature comprises a tab which engages a corresponding channel in the substrate to establish a desired angular orientation of the reinforcement member with respect to the substrate. ### Claim 15 (depends on 9) The apparatus of claim 9, wherein the substrate comprises a leg support pole of a stilt device leg attachment assembly, wherein the elongated member comprises a threaded fastener that secures an engagement assembly configured to engage a user's leg to the support pole, and wherein the retention member is configured to nest within a distal end of the support pole. ### Claim 16 (depends on 9) The apparatus of claim 9, wherein the substrate and the elongated member are each formed of metal, and wherein the reinforcement member comprises nylon.