Upwardly-acting door structure

Patent 3977123 Issued on August 31, 1976. Estimated Expiration Date:

August 31, 1993. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.

Abstract Claims Description Full Text

Patent References

1439373

2154421

3067813

3616575

3911831

Inventors

Assignee

Whiting Roll-up Door Mfg. Corp.

Application

No. 05/590384 filed on 06/25/1975

US Classes:

49/102, Cable interconnected105/410, Ends160/193, Strand160/194, Movably mounted track410/26, Multilevel deck; i.e., four-wheel support49/125MOUNTED FOR MOVEMENT TO FACIALLY STACKED POSITION

Examiners

Primary: Downey, Kenneth

Attorney, Agent or Firm

Sommer & Sommer

International Classes

B61D 3/02 (20060101)
B61D 17/04 (20060101)
B61D 3/18 (20060101)
B61D 19/00 (20060101)
B61D 3/00 (20060101)
B61D 17/06 (20060101)
E05D 15/18 (20060101)
E05D 15/16 (20060101)
E05F 11/38 (20060101)
E05F 11/48 (20060101)

Abstract

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 downward movement along the stationary tracks, an upper panel mounted on the movable tracks, a lower panel mounted to move upwardly and downwardly along the movable tracks at twice the speed, flexible chains arranged to interconnect the lower panel with the movable tracks, torsional springs arranged to counterbalance and support the aggregate weight of the raised movable tracks, and handles operatively arranged to raise and lower the movable tracks. The upper and lower panels may be raised to uncover the access opening, or lowered to cover the access opening.