Patent US3889223A successfully refreshed from Google Patents.
US3889223A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Resistor trimming technique
Assignee: Olivetti SpA
•
Filing: 1974-08-05
•
Granted: 1975-06-10
•
Expires: 1994-08-05
Abstract
Abstract A printed circuit resistor pattern, designed to be trimmed by electro-erosion, has affixed to the side thereof a highly conductive strip. The current path passes through a portion of the resistor pattern and through the conductive strip; as the resistor is trimmed, a gap is created along the edge of the conductive strip causing the current path to pass through a greater length of resistive material and a lesser length of the conductive strip, thereby causing the overall resistance to current flow to be increased.
Inventors
- 👤 Lino Sella
- 👤 Claudio Dalmasso
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 19:11
CPC Classifications
H; H01; H01C; H01C17/00; H01C17/22; H01C17/24; H01C17/2408; H05; H05K; H05K1/00; H05K1/16; H05K1/167; H05K3/00; H05K3/02; H05K3/08; Y; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/49002; Y10T29/49082; Y10T29/49099
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
188 words
A resistor trimming arrangement comprising: a resistor pattern having a first and second end with an initial resistance between these ends, said pattern including a first portion of relatively resistive material and a second portion of relatively conductive material so that an electrical current passing through said pattern from said first to said second end will pass through a first length of said resistive material and a second length of said conductive material; electrically operable means for removing an amount of said resistive material; and circuit means electrically connected to said removing means and electrically connected to the second end of the resistor pattern for operating said removing means to effect the removal of an amount of resistive material to increase the length of resistive material through which an electrical current passing between said ends passes to a length of said resistive material which is greater than said first length and to decrease the length of conductive material through which the electrical current passes to a length of said conductive material which is shorter than said second length, thereby causing the resistance between said ends to be increased.
Claim 2
Dependent Claim
188 words
A resistor trimming arrangement comprising: a resistor pattern having a first and second end with an initial resistance between these ends, said pattern including a first portion of relatively resistive material and a second portion of relatively conductive material so that an electrical current passing through said pattern from said first to said second end will pass through a first length of said resistive material and a second length of said conductive material; electrically operable means for removing an amount of said resistive material; and circuit means electrically connected to said removing means and electrically connected to the second end of the resistor pattern for operating said removing means to effect the removal of an amount of resistive material to increase the length of resistive material through which an electrical current passing between said ends passes to a length of said resistive material which is greater than said first length and to decrease the length of conductive material through which the electrical current passes to a length of said conductive material which is shorter than said second length, thereby causing the resistance between said ends to be increased.
Claim 3
Dependent Claim
116 words
A resistor trimming arrangement comprising: a relatively resistive element having a given resistance between its extremities; a relatively conductive element positioned in electrical contact with said resistive element, the path Of least resistance between said extremities including a first length of said conductive element; electrically operating means for removing an amount of said resistive element; and means electrically connected to said removing means and to one extremity of said resistive element for operating said removing means to create an electrical open circuit through a portion of said resistive element so that the path of least resistance between said extremities includes a second length of said conductive element, said second length being shorter than said first length.
Claim 4
Dependent Claim
116 words
A resistor trimming arrangement comprising: a relatively resistive element having a given resistance between its extremities; a relatively conductive element positioned in electrical contact with said resistive element, the path Of least resistance between said extremities including a first length of said conductive element; electrically operating means for removing an amount of said resistive element; and means electrically connected to said removing means and to one extremity of said resistive element for operating said removing means to create an electrical open circuit through a portion of said resistive element so that the path of least resistance between said extremities includes a second length of said conductive element, said second length being shorter than said first length.
Claim 5
Dependent Claim
97 words
A resistor trimming technique for increasing the electrical resistance between at least two points including the steps of: providing a relatively resistive element extending between said points; providing a relatively conductive element in contact with a portion of said resistive element so that electrical current passing between said two points through said resistive element will also pass through said conductive element; electro-eroding a gap in said resistive element adjacent and parallel to a portion of said conductive element so that said electrical current will not pass through a portion of said conductive element adjacent to said gap.
Claim 6
Dependent Claim
97 words
A resistor trimming technique for increasing the electrical resistance between at least two points including the steps of: providing a relatively resistive element extending between said points; providing a relatively conductive element in contact with a portion of said resistive element so that electrical current passing between said two points through said resistive element will also pass through said conductive element; electro-eroding a gap in said resistive element adjacent and parallel to a portion of said conductive element so that said electrical current will not pass through a portion of said conductive element adjacent to said gap.
Claim 7
Dependent Claim
102 words
A combination for increasing the resistance between at least two points comprising: a strip of resistive material extending between said two points, said strip having a shoulder; a strip of conductive material extending between one of said points and said shoulder, said conductive strip being contiguous to said resistive strip between said shoulder and said one of said points; means for electro-eroding a gap through said resistive strip starting at said shoulder and extending parallel to said conductive strip; and circuit means causing the electrical energy released by said electro-erosion to pass to said one of said points through said conductive strip.
Claim 8
Dependent Claim
102 words
A combination for increasing the resistance between at least two points comprising: a strip of resistive material extending between said two points, said strip having a shoulder; a strip of conductive material extending between one of said points and said shoulder, said conductive strip being contiguous to said resistive strip between said shoulder and said one of said points; means for electro-eroding a gap through said resistive strip starting at said shoulder and extending parallel to said conductive strip; and circuit means causing the electrical energy released by said electro-erosion to pass to said one of said points through said conductive strip.
Claim 9
Independent Claim
114 words
A method of increasing the resistance between selected points on a circuit board comprising the steps of: constructing a strip of relatively resistive material between said points, said strip having a relatively narrow portion and a relatively wide portion; constructing a strip of relatively conductive material; said strips being constructed in electrical contact with each other with said conductive strip being contiguous to said wide portion and extending from the area where said wide portion meets said narrow portion to the end of said wide portion; forming a gap in said resistive strip, said gap extending parallel to said conductive strip and starting from said area where said wide portion meets said narrow portion.
Claim 10
Independent Claim
114 words
A method of increasing the resistance between selected points on a circuit board comprising the steps of: constructing a strip of relatively resistive material between said points, said strip having a relatively narrow portion and a relatively wide portion; constructing a strip of relatively conductive material; said strips being constructed in electrical contact with each other with said conductive strip being contiguous to said wide portion and extending from the area where said wide portion meets said narrow portion to the end of said wide portion; forming a gap in said resistive strip, said gap extending parallel to said conductive strip and starting from said area where said wide portion meets said narrow portion.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-06-09 | 1978-12-09 | 1979-06-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-06-09 | 1982-12-09 | 1983-06-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-06-09 | 1986-12-09 | 1987-06-10 | $7700.00 | Window Closed / Lapsed |