Marvin Phillip Thomas

US Patent:

40249000, May 24, 1977

Filed:

Jul 17, 1975

Appl. No.:

5/596322

Inventors:

Marvin C. Thomas - Lyons CO

International Classification:

B60C 2720

US Classification:

152214

Abstract:

Method and apparatus for providing selectively engageable and disengageable traction surface, on the periphery of a vehicle wheel by means of an apparatus mounted to a fixed portion of a vehicle, selective positioning of a journalled outer portion of the apparatus to engage and rotate with the outer, or tire, portion of the wheel, or, alternatively, to retract to a stored inactive position. The apparatus further provides for positive deployment with spring-loaded extension pressure, accommodation of localized variations in diameter and resilient mounting of traction bars.

US Patent:

43554512, Oct 26, 1982

Filed:

May 12, 1980

Appl. No.:

6/148874

Inventors:

Marvin C. Thomas - Lyons CO

International Classification:

B23P 1902
B23P 1904
B60C 2720
B60C 2714

US Classification:

294266

Abstract:

Device and method utilizing a fixed assembly attachable to a vehicle wheel back support plate, and a journaled, rotatable assembly carrying a track which may be deployed to engage and rotate with the wheel, or retracted for stable storage. The track is supported by leading and trailing arms carried on the rotatable assembly of the device, which arms in turn are movable concentrically to the device journal to expand the track around the tire and move inwardly upon completion of the track expansion to encircle the tire. Tracks utilizing linkages and rigid traction bars, or resilient members may be employed. Deployment and retraction power may be manual or provided by springs preloadable utilizing the rotational energy of the wheel, by fluid means, i. e. hydraulic vacuum and pneumatic, or by electric power, with the deployment and retraction being powered by a common means, or with the two movements or portions thereof being powered by a combination of power means.