Daniel C Schaeffer

US Patent:

50608460, Oct 29, 1991

Filed:

Apr 23, 1990

Appl. No.:

7/512722

Inventors:

Daniel J. Schaeffer - Arlington Heights IL
Raymond M. Fardoux - Wilmette IL
Robert P. Dein - Elmhurst IL
Linda D. Limper - Glenview IL

Assignee:

Motorola, Inc. - Schaumburg IL

International Classification:

B23K 308

US Classification:

228447

Abstract:

The present invention discloses a device for positioning a multi-planar or multi-leaded surface mount electronic component on a printed circuit board (PCB) during reflow soldering. By design this non-conductive device made of thermoplastic resins comprises a fence, having a cavity, wherein the electronic component is positioned relative to printed circuit board foot print contacts. Attached to the bottom surface of the fence is a pair of collapsible slotted pegs. These pegs extend vertically downward from the fence and are adapted to provide a snap-fit insertion and retention mechanism whereby the fence is held in place by inserting the collapsible pegs into holes in a printed circuit board. Thereafter, a pair of cantilever beams which are attached to the fence sidewalls and extend into the fence cavity, make contact with the electronic component. As the fence is inserted into the printed circuit board, the cantilever beams press and hold the electronic component in place during reflow soldering.

US Patent:

43993540, Aug 16, 1983

Filed:

Mar 17, 1980

Appl. No.:

6/131249

Inventors:

Daniel Schaeffer - Chicago IL

Assignee:

Vorne Industries, Inc. - Chicago IL

International Classification:

H03K 2130

US Classification:

377 26

Abstract:

A digital rate monitor including a microprocessor operating under program control to receive and process event pulses to calculate the rate of the event pulses, and display the calculated rate. The rate is calculated by accumulating a batch of pulses and measuring the time it takes to accumulate such number of pulses. The batch size for a given calculation is a function of the event pulse rate, and a different batch size is automatically selected if the event pulse rate increases or decreases within a certain range. The rate is calculated once per second by averaging sixteen pulses for high speed inputs, four pulses for intermediate rates, and using a single pulse for low speed inputs.