Patent US3916144A successfully refreshed from Google Patents.
US3916144A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for adjusting resistors by lasers
Assignee: Draloric Electronic GmbH
•
Filing: 1974-03-26
•
Granted: 1975-10-28
•
Expires: 1994-03-26
Abstract
Abstract A method for adjusting the resistance of cylindrical layer resistors comprising utilization of a laser beam. The resistor is rotated about its longitudinal axis at a predetermined rotational speed. Simultaneously therewith, a pulsating laser beam is moved at a predetermined linear speed along a line parallel to the longitudinal axis of the resistor element. The resistor rotational speed is preferably an integral multiple of the linear speed of the laser beam. The impulse time (t) of the laser beam preferably lies within the range from 0.1 to 0.9 of the period time (T). The above relationships produce a resistance element of high quality and having a uniform current density preventing premature burn out of the elements.
Inventors
- 👤 Walter Schuermann
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 11:27
CPC Classifications
H; H01; H01C; H01C17/00; H01C17/22; H01C17/24; H01C17/242; H01C17/245; Y; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/49002; Y10T29/49082; Y10T29/49099
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
187 words
A method for adjusting the resistance value of resistance elements having a single cylindrical resistance layer whereby a substantially uniform current density distribution is obtained over the entire surface of the resistance layer, comprising the steps of: a. generating a pulsating laser beam having a time period (T) between successive pulses and directing said laser beam toward said resistance layer; b. rotating the resistance element about its longitudinal axis with a rotation time (Tu) required to complete one full revolution equal to a rational multiple number (n) of the pulsating laser beam time period (T), according to the formula T n.T; where the number n is greater than 1: c. selecting a common impulse duration time (t) in the range of 0.1 to 0.9 times the time period (T) of the laser beam for all pulses of said pulsating laser beam to form at least one discontinuous adjustment groove in said resistance layer, each adjustment groove encircling less than one-half the circumference of the resistance layer; and d. linearly moving the pulsating laser beam in a direction substantially parallel to the longitudinal axis of the resistance element.
Claim 2
Independent Claim
187 words
A method for adjusting the resistance value of resistance elements having a single cylindrical resistance layer whereby a substantially uniform current density distribution is obtained over the entire surface of the resistance layer, comprising the steps of: a. generating a pulsating laser beam having a time period (T) between successive pulses and directing said laser beam toward said resistance layer; b. rotating the resistance element about its longitudinal axis with a rotation time (Tu) required to complete one full revolution equal to a rational multiple number (n) of the pulsating laser beam time period (T), according to the formula T n.T; where the number n is greater than 1: c. selecting a common impulse duration time (t) in the range of 0.1 to 0.9 times the time period (T) of the laser beam for all pulses of said pulsating laser beam to form at least one discontinuous adjustment groove in said resistance layer, each adjustment groove encircling less than one-half the circumference of the resistance layer; and d. linearly moving the pulsating laser beam in a direction substantially parallel to the longitudinal axis of the resistance element.
Claim 3
Dependent Claim
15 words
A method of claim 1 wherein said discontinuous adjustment grooves lie along a helical path.
Claim 4
Dependent Claim
23 words
The method of claim 1 in which the impulse time preferably lies in the range from 0.3 to 0.8 of the period time.
Claim 5
Dependent Claim
68 words
The method of claim 1, wherein step (b) further comprises the step (e) of selecting the multiple number (n) in accordance with the formula n (Tu/T - 1/n2), where n is a first integral number greater than one and n2 is a second integral number greater than one, to obtain meander-like current paths along the surface of said resistance layer for minimizing inductive effects of the adjustment grooves.
Claim 6
Dependent Claim
51 words
The method of claim 1, wherein step (b) further comprises the step of selecting the rational multiple number (n) in accordance with the formula n (Tu/T - 1/2 ), where n is an integral number greater than 1, for maximizing current loadability of said resistance element even while minimizing inductive effects.
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) | 1978-10-27 | 1979-04-28 | 1979-10-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-10-27 | 1983-04-28 | 1983-10-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-10-27 | 1987-04-28 | 1987-10-28 | $7700.00 | Window Closed / Lapsed |