Assignee
KEYSTONE IND INC
US·16 granted patents·223 citations·filing 1972–1998
Top patents by PatentIndex Score
16 records- 0173US5671684ARailway car outlet gate assembly with automatic lockKEYSTONE IND INC·Filed 1996·Granted Sep 30, 1997·31 cites·7 claims
- 0265US5584251ARailway car outlet gate assembly with automatic lockKEYSTONE IND INC·Filed 1995·Granted Dec 17, 1996·23 cites·32 claims
- 0357US5927523ARail car bufferKEYSTONE IND INC·Filed 1997·Granted Jul 27, 1999·19 cites·32 claims
- 0454US4026418AHydraulic cushioning unit with a gas returnKEYSTONE IND INC·Filed 1975·Granted May 31, 1977·13 cites·15 claims
- 0553US4224879ARailway hopper car door latchKEYSTONE IND INC·Filed 1978·Granted Sep 30, 1980·11 cites·9 claims
- 0651US5746335ADouble acting center-of-car cushioning deviceKEYSTONE IND INC·Filed 1996·Granted May 5, 1998·17 cites·14 claims
- 0751US4601461ALading protection deviceKEYSTONE IND INC·Filed 1984·Granted Jul 22, 1986·13 cites·18 claims
- 0850US5598937ASlackless drawbar assemblyKEYSTONE IND INC·Filed 1996·Granted Feb 4, 1997·16 cites·26 claims
- 0946US6012397ARailway car outlet gate assembly with inertial latchKEYSTONE IND INC·Filed 1998·Granted Jan 11, 2000·15 cites·45 claims
- 1046US3989287AAutomotive vehicle door retarding and closing mechanismKEYSTONE IND INC·Filed 1972·Granted Nov 2, 1976·14 cites·9 claims
- 1145US5908123ARail car buffer and methodKEYSTONE IND INC·Filed 1997·Granted Jun 1, 1999·13 cites·50 claims
- 1244US4312607APellet gate for pneumatic discharge hopper carKEYSTONE IND INC·Filed 1980·Granted Jan 26, 1982·14 cites·9 claims
- 1342US4304338ACenter-of-car cushioning device with gas returnKEYSTONE IND INC·Filed 1979·Granted Dec 8, 1981·8 cites·8 claims
- 1440US4033616AAutomotive vehicle door retarding and closing mechanismKEYSTONE IND INC·Filed 1976·Granted Jul 5, 1977·11 cites·6 claims
- 1535US4534298ALock and seal for hopper outletKEYSTONE IND INC·Filed 1983·Granted Aug 13, 1985·5 cites·4 claims
- 1626US4562929ABackstop assembly for use with cushioning device in sill of railway carKEYSTONE IND INC·Filed 1983·Granted Jan 7, 1986·0 cites·2 claims
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Counts cover granted patents and pending applications in the PatentIndex corpus. How scoring works →