William F Duffy

US Patent:

41004337, Jul 11, 1978

Filed:

Jan 4, 1977

Appl. No.:

5/756922

Inventors:

William Thomas Duffy - Tempe AZ
William Joseph Lillis - Tempe AZ

Assignee:

Motorola, Inc. - Schaumburg IL

International Classification:

G06G 712
G06G 724

US Classification:

307229

Abstract:

A monolithic circuit is disclosed which is suitable for providing a pair of logarithmic differential output current signals in response to an applied linear control voltage. The circuit comprises first and second operational amplifiers connected as voltage followers which act as low impedance driving sources. The linear control voltage is applied to a first one of the operational amplifiers and a reference voltage to the other. These two voltages substantially appear at the respective outputs of the operational amplifiers and are summed across a resistor connected therebetween to establish a difference potential thereacross of which the magnitude is a function of the applied input voltage. The difference potential is utilized to differentially drive the base emitter junctions of a pair of transistors which establish differential logarithmic currents at the collectors thereof.

US Patent:

53931858, Feb 28, 1995

Filed:

Oct 1, 1993

Appl. No.:

8/130182

Inventors:

William J. Duffy - Midlothian IL

Assignee:

Illinois Tool Works Inc. - Glenview IL

International Classification:

F16B 1900

US Classification:

411510

Abstract:

A push-in fastener including a head and a shank, the shank including at least one resilient fin integrally formed along its length for insertion and retention of the fastener within an aperture of an article where the fin includes at least one engagement rib formed on either side thereof for contact with the edges of the aperture and for absorbing any wear or shear caused by the edges upon insertion or removal of the fastener so the fin remains intact and maintains the originally designed insertion and retention forces.

US Patent:

52901378, Mar 1, 1994

Filed:

Apr 26, 1993

Appl. No.:

8/051976

Inventors:

William J. Duffy - Midlothian IL

Assignee:

Illinois Tool Works Inc. - Glenview IL

International Classification:

F16B 1306
F16B 1900

US Classification:

411 60

Abstract:

A pin bushing having a body portion including a head member, a shank member and a tapered axial bore extending therethrough. First and second substantially perpendicular lateral slots extend through the body portion where the first slot enables insertion and initial retention of the shank within an aperture in an article and the second slot enables a pin to be releasably retained within the shank to lock the bushing within the aperture.