US3595147A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Photoelectric drafting apparatus
Assignee: Individual
•
Filing: 1968-08-23
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Granted: 1971-07-27
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Expires: 1988-08-23
Abstract
Abstract The apparatus includes a light source, a first aperture diaphragm and a condenser lens, the lens producing a real image of the aperture upon passing light through the diaphragm, a partially silvered mirror disposed at the rear of the condenser at an angle of 45* to the optical axis thereof to transmit part of the light beam emerging from the condenser lens and to reflect the remaining part of this light beam through an angle of 90*, a second aperture diaphragm to receive the reflected part of the light beam and for determining the thickness of the drawn stroke, a mirror and lens for forming an image of the second aperture on the photographic layer of a photoelectric cell to continuously measure the light intensity and disposed in the path of the light beam which is transmitted by the partially silvered layer which cell controls a servometer for a movable wedge filter which is arranged behind the first aperture diaphragm and which adjusts the light intensity which passes from the aperture of the first diaphragm onto the condenser lens.
Inventors
- 👤 Karl Blattner
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 14:28
CPC Classifications
G; G06; G06K; G06K15/00; G06K15/22; G06K15/225; G03; G03B; G03B15/00; G03B7/00; G03B7/08; G03B7/081; G03B7/087
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
250 words
An apparatus for automatically controlling the exposure of an aperture diaphragm which is arranged on the work carriage of an automatic, photoelectric drafting machine or the like, in which an image of the aperture diaphragm is formed for the purpose of drawing a stroke on to a photographic layer, the apparatus comprising: a light source, a first aperture diaphragm and a condenser lens, the lens producing a real image of the aperture upon passing light through the diaphragm, a partially silvered mirror disposed at the rear of the cOndenser lens at an angle of 45* to the optical axis thereof to transmit part of the light beam emerging from the condenser lens and to reflect the remaining part of this light beam through an angle of 90*; means to determine the thickness of a drawn stroke comprising a second aperture diaphragm to receive the reflected part of the light beam; mirror and lens means for forming an image of said second aperture on the photographic layer; a photoelectric cell disposed in the path of the light beam which is transmitted by the partially silvered mirror to continuously measure the light intensity of the light beam and control, through the intermediary of an electronic control device; means to adjust to a prescribed value the light intensity of the light beam which passes from the aperture of the first aperture diaphragm on to the condenser lens comprising a servometer for a movable wedge filter which is arranged behind the first aperture diaphragm.
Claim 2
Independent Claim
250 words
An apparatus for automatically controlling the exposure of an aperture diaphragm which is arranged on the work carriage of an automatic, photoelectric drafting machine or the like, in which an image of the aperture diaphragm is formed for the purpose of drawing a stroke on to a photographic layer, the apparatus comprising: a light source, a first aperture diaphragm and a condenser lens, the lens producing a real image of the aperture upon passing light through the diaphragm, a partially silvered mirror disposed at the rear of the cOndenser lens at an angle of 45* to the optical axis thereof to transmit part of the light beam emerging from the condenser lens and to reflect the remaining part of this light beam through an angle of 90*; means to determine the thickness of a drawn stroke comprising a second aperture diaphragm to receive the reflected part of the light beam; mirror and lens means for forming an image of said second aperture on the photographic layer; a photoelectric cell disposed in the path of the light beam which is transmitted by the partially silvered mirror to continuously measure the light intensity of the light beam and control, through the intermediary of an electronic control device; means to adjust to a prescribed value the light intensity of the light beam which passes from the aperture of the first aperture diaphragm on to the condenser lens comprising a servometer for a movable wedge filter which is arranged behind the first aperture diaphragm.
Claim 3
Dependent Claim
119 words
Apparatus according to claim 1, in which the second aperture diaphragm is continuously adjustable by a programmed control device of the drafting machine or the like in accordance with the stroke thickness required at any given time, and the condenser lens which forms an image of the first aperture diaphragm is movable in a guide along its optical axis by a servomechanism which is controlled by the said programmed control device of the drafting machine, synchronously with the movement of the rotary diaphragm, drum diaphragm or iris diaphragm, to bring the lens into a position such that the light reflected by the partially silvered mirror falls wholly upon the aperture of the rotary diaphragm, drum diaphragm or iris diaphragm.
Claim 4
Dependent Claim
28 words
Apparatus according to claim 1, in which the partially silvered mirror discriminates between the different wavelengths of the light incident thereon and transmits the long wavelength light components.
Claim 5
Dependent Claim
39 words
Apparatus in accordance with claim 2 in which a device for regulating the quantity of light falling upon the aperture of said second aperture diaphragm in agreement with the size of this aperture is located before said second diaphragm.
References Cited (Backward Citations)
US3205767A
Cited
US3323414A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-07-26 | 1975-01-25 | 1975-07-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-07-26 | 1979-01-25 | 1979-07-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-07-26 | 1983-01-25 | 1983-07-27 | $7700.00 | Window Closed / Lapsed |