James Joseph Wulfing

45277559, Jul 9, 1985

Oct 17, 1983

6/542414

Robert M. Rood - Woodbury MN
James J. Wulfing - Afton MN

Minnesota Mining and Manufacturing Company - St. Paul MN

G03B 104
G11B 1532

242199

A videotape cassette has a visor-type door, at each end of which is an ear or corner part at which a pin hinges the door to a housing. As in the prior art, the door is biased to either a fully opened or fully closed position. In the novel cassette, the biasing results from a free-standing finger formed in a wall of the housing, which finger acts as a spring against a squarish platform on the inner face of an ear of the door.

45209693, Jun 4, 1985

Oct 17, 1983

6/542430

James J. Wulfing - Afton MN
Robert M. Rood - Woodbury MN

Minnesota Mining and Manufacturing Company - St. Paul MN

B65H 7518
G03B 104
G11B 1532

242 718

Videocassette tape spool, the wear button of which is a protuberance of a small plastic piece which may serve to lock the parts of the spool together. By using a small piece for the wear button, substantial savings in raw material can be realized since highly wear-resistant plastics tend to be quite expensive. The novel tape spool also can be assembled less expensively compared to tape spools now used in videocassettes.

45153302, May 7, 1985

Oct 17, 1983

6/542416

James J. Wulfing - Afton MN
Robert M. Rood - Woodbury MN

Minnesota Mining and Manufacturing Company - St. Paul MN

G03B 104
G11B 1532
B65H 1722

242197

A tape roller has a plastic sleeve which is journalled between bearings formed in opposing walls of a plastic cassette housing. The wall is cored out around at least one of those bearings so that the bearing is supported only by bridges which bow outwardly to receive an oversize sleeve. Preferably there are two such bridges at the bearing, the thicknesses of which are about 20% that of the wall.

56402988, Jun 17, 1997

Jul 28, 1995

8/509032

James J. Wulfing - Stillwater MN

Imation Corp. - Oakdale MN

G11B 2303

360133

A cartridge including a cover casing, a back casing, and a disc-shaped medium provided between the casings. The cover casing has a centrally-located, raised surface on its interior surface which is chemically and physically integral with the cover casing. When the cartridge is inserted into a drive for reading/writing the medium, a drive pin from the drive contacts the raised surface. The cover casing is comprised of high-impact polystyrene containing silicone.

44727534, Sep 18, 1984

Oct 24, 1983

6/544867

James J. Wulfing - Afton MN

Minnesota Mining and Manufacturing Company - St. Paul MN

G11B 2302
G11B 1512
G03B 104
B65H 1748

360132

The length of tape that can be wound into a videotape cassette such as Betamax or VHS can be increased by modifying the casette to employ the braking mechanism of the invention. This involves a flanged reel in which teeth are formed only in the outer face of one flange, and a brake lever which has a finger formed with a tooth-engaging ramp that is inclined at 30. degree. -60. degree. to the inner face of said flange when the finger fits between adjacent teeth.

45153230, May 7, 1985

Oct 17, 1983

6/542415

Robert M. Rood - Woodbury MN
James J. Wulfing - Afton MN

Minnesota Mining and Manufacturing Company - St. Paul MN

B65H 7528

242 741

A prior tape spool comprises two hub parts which are wedged together to pinch a tape leader between the walls of a narrow passage that opens through the tape-winding surface. The novel tape spool differs from the prior tape spool in that the passage pinches the leader only in a region remote from the opening through the tape-winding surface, so that if the leader is accidentally crimped or off center, it would tend to straighten out before emerging from the opening.

51895862, Feb 23, 1993

Feb 21, 1991

7/658547

Paul D. Rumpza - Roseville MN
James J. Wulfing - Stillwater MN

Minnesota Mining and Manufacturing Company - St. Paul MN

G11B 2303

360133

A disk cartridge including a rotatable disk, a cartridge case for housing the disk, and a U-shaped shutter slidably disposed on the front wall of the cartridge case is disclosed. The cartridge case includes upper and lower walls, and a head access opening formed in both walls between a central axis and the front wall to access the disk. The access opening is opened and closed by the shutter which is biased closed. An indented portion is formed on the walls for receiving the shutter. Two tabs are formed in one shutter arm portion and are received in a slot formed in the cartridge case.

47520469, Jun 21, 1988

Jun 10, 1986

6/872543

James J. Wulfing - Afton MN

Minnesota Mining and Manufacturing Company - St. Paul MN

B65H 7518

242 718

A tape spool provides resistance to disassembly from shocks caused by rough handling by providing an annular hub projection extending axially of the spool hub to define a shoulder which interacts with an inner radial wall of a disk providing the second flange of the spool. The inner radial wall of the disk defines a central hole surrounding the hub projection, with contact between the radial wall of the disk and the shoulder of the hub restricting radial movement of the disk with respect to the hub. The disk and the hub also may include intermeshing splines which prevent relative rotation of the disk and the hub.