David R Cronin

US Patent:

55837336, Dec 10, 1996

Filed:

Dec 21, 1994

Appl. No.:

8/361426

Inventors:

David V. Cronin - Peabody MA

Assignee:

Polaroid Corporation - Cambridge MA

International Classification:

H01L 2300

US Classification:

361111

Abstract:

An electrostatic discharge protection device is disclosed which automatically connects selected connector pins of a semiconductor chip package ("SCP") or connectors on printed circuit boards such that the connector pins are held at a common voltage until insertion of the SCP into a receptor or until insertion of a cable into the connector which overcomes an internal resilient bias of the electrostatic discharge protection device causing the common connection to be removed. Removal of the SCP from the receptor or the cable from its connector removes the force which overcomes the bias, thereby reestablishing the common electrical connection thus automatically moving the electrostatic discharge protection device between inoperative and operative positions.

US Patent:

45417016, Sep 17, 1985

Filed:

Mar 26, 1984

Appl. No.:

6/593519

Inventors:

David V. Cronin - Peabody MA

Assignee:

Polaroid Corporation - Cambridge MA

International Classification:

G03D 900
G03D 302

US Classification:

354324

Abstract:

A processing apparatus is provided for immersion treating a photograhic film unit with a low viscosity processing liquid. The apparatus comprises a flexible bag-like liquid container having a film unit receiving section and a communicating liquid reservoir section, and a device for manipulating the container to selectively change the configuration of the container and the distribution of liquid therein. The device includes a pivoting frame which moves components of the receiving section between an open position for facilitating film insertion and withdrawal and a closed position defining the receiving section which is flooded with liquid from the reservoir section to treat a film unit therein.

US Patent:

53881192, Feb 7, 1995

Filed:

May 17, 1994

Appl. No.:

8/245022

Inventors:

David V. Cronin - Peabody MA
Louis J. Brozyna - Somerville MA

Assignee:

Polaroid Corporation - Cambridge MA

International Classification:

H01S 309

US Classification:

372 69

Abstract:

In a laser light pump, a multiplicity of micromanipulators adjust the positions of a cylindrical lens and line of optical fiber ends relative to each other and relative to a light source composed of a line of laser diode facets. Each micromanipulator achieves extremely fine resolution by imposing a vernier or differential screw arrangement into a flexure ratio divider, and thereby multiplying its resolving capability. The vernier screw arrangement spreads two members of different stiffnesses, and the stiffer one of the members moves the lens or the line of fiber ends.

US Patent:

49715682, Nov 20, 1990

Filed:

Dec 11, 1989

Appl. No.:

7/448228

Inventors:

David V. Cronin - Peabody MA

Assignee:

Polaroid Corporation - Cambridge MA

International Classification:

H01R 13703

US Classification:

439188

Abstract:

For an electrical connector member which has a plurality of pins which mates with a complementary receptacle member, there is provided a shorting member comprising a thin conductive sheet having a base portion fixedly connected with respect to the connector member in spaced relation with respect to the pins and a plurality of thin elongated arm portions each integrally connected at one end to the base portion and cantilevered therefrom to extend past at least a respective one of the pins, the other end of each arm portion extending laterally outward so as to electrically contact a side of the pin past which that arm portion extends, each of the arm portions having an inherent spring bias so as to urge its laterally extending end portion away from the connector member and into electrical contact with a respective pin so as to short a select number of pins upon disconnection of the connector and receptacle members.

US Patent:

55992056, Feb 4, 1997

Filed:

Jul 20, 1994

Appl. No.:

8/278063

Inventors:

David V. Cronin - Peabody MA

Assignee:

Polaroid Corporation - Cambridge MA

International Classification:

H01R 13703

US Classification:

439507

Abstract:

A plurality of electrostatic discharge protection devices are disclosed for use with semiconductor chip packages of a type having a top surface, a bottom surface, and disposed between the top surface and the bottom surface a plurality of lateral surface with extending therefrom a plurality of connector pins disposed thereon. The electrostatic discharge protection devices disclosed herein are heat sensitive in that they automatically withdraw from electrical contact with the connecting pins upon introduction of sufficient heat such as that of soldering. In addition, disclosed herein is a electrostatic discharge protection device for manual withdrawal should the electrostatic discharge protection be required after the soldering process has been terminated.

US Patent:

51638509, Nov 17, 1992

Filed:

Nov 27, 1991

Appl. No.:

7/800612

Inventors:

David V. Cronin - Peabody MA

Assignee:

Polaroid Corporation - Cambridge MA

International Classification:

H01R 909
H01R 13703

US Classification:

439507

Abstract:

A plurality of electrostatic discharge (hereafter referred to as "ESD") protection devices are disclosed for use with semiconductor chip packaging (hereafter referred to as "SCP"). The electrostatic protection devices comprise electrically conductive shorting devices that may be removably connected to the SCP during the manufacture to short selected pins from the SCP. The ESD protection devices remain in place to provide ESD protection during all phases of handling and shipping and may be either automatically unshorted or be manually removed during final assembly when the SCP is installed in its end product.

US Patent:

48434949, Jun 27, 1989

Filed:

Oct 15, 1987

Appl. No.:

7/109289

Inventors:

David V. Cronin - Peabody MA
John M. Guerra - Concord MA
Paul F. Sullivan - Westwood MA
Patricia A. Mokry - Medford MA
Peter P. Clark - Acton MA
Vincent L. Cocco - Wakefield MA

Assignee:

Polaroid Corporation - Cambridge MA

International Classification:

G11B 1300

US Classification:

360 7703

Abstract:

A magnetic data storage system for use with a double sided disk in which a prerecorded pattern of opaque optical lines is used to define the tracks in which magnetic data is to be stored. A separate optical system including an illumination source and a photosensitive detector is provided on a read/write assembly for each side of the disk. Each detector is designed also to serve as a reference grating. The illumination source is designed to image the prerecorded pattern of optical lines on the reference grating as an indication of the alignment of the read/write head of the assembly and a desired data rack and any misalignment of the head and track generates a servo signal. The detector uses four separate photocells interleaved in a prescribed fashion to form a quadrature detector that is adjustable to compensate for various non-uniformities. One form of illumination source uses a surface-emitting light emitting diode and optics for forming a multiple beam source.

US Patent:

54900336, Feb 6, 1996

Filed:

Apr 28, 1994

Appl. No.:

8/234917

Inventors:

David V. Cronin - Peabody MA

Assignee:

Polaroid Corporation - Cambridge MA

International Classification:

H05F 300

US Classification:

361212

Abstract:

An electrostatic discharge protection device that fits within a connector for high frequency cables having a tubular ground conductor surrounding one or more core conductors. The electrostatic discharge protection device creates a shunt across the one or more core conductors and the ground conductor thus electrically grounding any electrostatic discharge on the one or more core conductors. Upon joining of a complimentary receptor to the connector, the electrostatic discharge protection device automatically withdraws the shunt reestablishing electrical isolation among the one or more core conductors and the ground conductor.