Quotables
"The production of too many useful things results in too many useless people."
Karl Marx
PatentStorm News
Make the Most of Our Site
See this month's Top Inventors and Most Cited Patents.
Stay on top of the latest innovations by subscribing to an RSS feed.
Registered users: Manage your profile.
| Number | Title | Issue Date |
| 5201897 | Spring balancer for a roll-up door An improved spring balancer (10) includes a shaft (13) rotatably mounted on a support (11). A first torsional spring (14) acts between the support and the shaft. A second torsional spring (19) acts between the support and a cable drum assembly (63) journa... | 04/13/1993 |
| 4930561 | Roll-up door joint construction An improved joint construction (10) for a roll-up door includes specially-configured upper and lower panel sections (12, 11), a specially-configured hinge member (13) adapted to be longitudinally inserted into operative engagement wiht lower panel section... | 06/05/1990 |
| 3977123 | Upwardly-acting door structure An upwardly-acting door structure is adapted to close an access opening of a body member, such as an automobile-carrying railroad car. The door structure includes a stationary track on either side of the opening, movable tracks mounted for upward and down... | 08/31/1976 |
