Richard E Caddock

US Patent:

53613007, Nov 1, 1994

Filed:

Mar 26, 1993

Appl. No.:

8/037927

Inventors:

Richard E. Caddock - Winchester OR

Assignee:

Caddock Electronics, Inc. - Riverside CA

International Classification:

H01C 112

US Classification:

379412

Abstract:

A balancing resistor and thermistor network for telephone circuits, and combination with an external relay, which reliably handles all three levels of adverse conditions, automatically resets under certain conditions, is physically small in size, and is strong. It is a flat ceramic substrate on both surfaces of which are screen-printed thick-film balancing resistor films. Also screen-printed on both surfaces are termination traces having portions so located that when the substrate substantially instantaneously fractures it reliably and substantially instantaneously breaks the circuits through the resistive films, the fracture occurring in response to a sudden high-voltage overload. Accordingly, there is no damage to, or melting or burning of, small wires in the telephone circuits at points near to or remote from the balancing resistor network. A thermistor film is screen-printed directly onto the substrate at a central region where there is no resistive film.

US Patent:

52529444, Oct 12, 1993

Filed:

Apr 6, 1992

Appl. No.:

7/863834

Inventors:

Richard B. Caddock - Winchester OR

Assignee:

Caddock Electronics, Inc. - Riverside CA

International Classification:

H01C 1034

US Classification:

338275

Abstract:

The film-type electrical power resistor includes a flat chip of aluminum oxide, having a resistive film screen-printed onto one of its sides. Leads are bonded to that side and electrically connected to the film, the leads being such that the chip may be cantilevered by the leads in a mold cavity before introduction of synthetic resin into the cavity, and with the lower chip surface spaced above the bottom cavity wall. A molded body is molded in the cavity to fully encapsulate the chip, film, and inner ends of the leads, there being no mold cup around the molded body. The molded body is formed of high thermal-conductivity thermosetting synthetic resin. Provided through the body is a bolthole for clamping of the resistor to an external chassis or heatsink. The space between the bottom surface of the chip and the flat bottom surface of the molded body is a heat-sinking volume formed of the high thermal-conductivity resin; and the bottom surface of such volume of resin is the bottom surface of the resistor. The stated volume does not contain any metal that is either in an electric circuit, or projects outwardly relative to the edges of the chip.

US Patent:

55944078, Jan 14, 1997

Filed:

Jul 12, 1994

Appl. No.:

8/274018

Inventors:

Richard E. Caddock - Winchester OR

Assignee:

Caddock Electronics, Inc. - Riverside CA

International Classification:

H01C 710

US Classification:

338 24

Abstract:

A resistor combination and method, that is formed by a substrate having a resistive film on it, and pins extruding from one edge of the substrate and connected to the film. A U-shaped cold region is provided on the substrate around at least much of the film, and is so constructed that application of common high overload voltages to the pins causes vertical fracture of the substrate. The resulting substrate pieces are held by the pins to the circuit board. In one embodiment, a synthetic resin housing is provided around the substrate.

US Patent:

52549690, Oct 19, 1993

Filed:

Mar 12, 1993

Appl. No.:

8/032537

Inventors:

Richard E. Caddock - Winchester OR

Assignee:

Caddock Electronics, Inc. - Riverside CA

International Classification:

H01C 1012

US Classification:

338308

Abstract:

An apparatus and method by which a flat film-type resistor is intentionally caused to thermal-shock fracture in response to a predetermined high-voltage overload condition. A stressed spring wire is mounted on such film-type resistor and connected in circuit with it. A predetermined solder and temperature gradient are employed to hold the spring wire in bent condition until the solder melts, whereupon the spring flexes and the circuit breaks. Heatsink portions are provided in the circuit board for such resistor, and receive terminal pins thereof.

US Patent:

53009193, Apr 5, 1994

Filed:

May 5, 1992

Appl. No.:

7/879185

Inventors:

Richard E. Caddock - Roseburg OR

Assignee:

Caddock Electronics, Inc. - Riverside CA

International Classification:

H01C 1028

US Classification:

338250

Abstract:

The power resistor has a metal housing and heatsink, the bottom wall of which is planar and has a bolt hole therethrough for tight securing of the resistor to a chassis. A planar film-type power resistor is mounted in the housing and encapsulated therein, being held close to the bottom wall of the housing. Heat from the film-type resistor passes through the bottom wall into the chassis, the result being that the power rating of the resistor is high. The metal housing is die-cast of a zinc alloy, at extremely low cost yet with substantially the same heat-transmission characteristic as that of conventional die-castable aluminum alloys.

US Patent:

62534467, Jul 3, 2001

Filed:

Jan 25, 1999

Appl. No.:

9/237977

Inventors:

Richard E. Caddock - Winchester OR

International Classification:

H01O 1700

US Classification:

296101

Abstract:

A fault current fusing resistor, comprising a substrate on which there is a line of resistive film formed of metal and glass in a conductive film, which line is closely confined by containing and sealing substances to prevent venting of vapor from the line during the fusing caused by an electrical fault condition.

US Patent:

54812410, Jan 2, 1996

Filed:

Nov 12, 1993

Appl. No.:

8/151430

Inventors:

Richard E. Caddock - Winchester OR

Assignee:

Caddock Electronics, Inc. - Riverside CA

International Classification:

H01C 108

US Classification:

338 51

Abstract:

A low-cost heat sink-mounted power film resistor having a high power rating for its footprint size, and not incorporating any housing. The resistor is bolted or otherwise secured tightly to an external heat sink in high heat-conduction relationship, the external heat sink being contacted flatwise by a rectangular internal heat sink. The footprint size and shape of the internal heat sink correspond substantially to those of commercially-marketed power film resistors having molded synthetic resin housings. The internal heat sink is bonded in high heat-conductivity relationship to a ceramic chip having a resistive film on the side thereof remote from the heat sink. Over such resistive film is a thin environmental coating. The leads are provided and connected to spaced portions of the film, on metalization pads.

US Patent:

56213786, Apr 15, 1997

Filed:

Apr 20, 1995

Appl. No.:

8/425913

Inventors:

Richard E. Caddock - Winchester OR
Richard E. Caddock - Roseburg OR

Assignee:

Caddock Electronics, Inc. - Riverside CA

International Classification:

H01C 108

US Classification:

338 51

Abstract:

A power resistor having much improved heat dissipation ability to an underlying heatsink because a step or protuberance is provided that cooperates with the mounting bolt or screw to largely nullify the effects of molding-caused camber or curvature.