Patent US1610971A successfully refreshed from Google Patents.
Patent US3829220A successfully refreshed from Google Patents.
US3829220A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Gauging dimensions
Assignee: TI Group Services Ltd
•
Filing: 1973-03-16
•
Granted: 1974-08-13
•
Expires: 1993-03-16
Abstract
Abstract A profile gauge in which two beams are scanned in unison, one of them being scanned in a parallel manner across an object being measured and producing a profile signal in a first light detector, and the other being scanned in a parallel across a diffraction grating which transmits light that produces a pulsed measuring signal in a second light detector, one pulse being produced for each line spacing interval of the grating traversed by the second beam and these measuring pulses being produced continuously during scanning so as to permit direct measurement of the width of the object by summing those pulses occuring when the first beam is interrupted by the object. Preferably, the second beam is a monochromatic beam and an additional diffraction grating is provided in the path of said second light beam before it is scanned across the first grating so that diffraction of the light in both gratings causes a first order diffraction spot to be focussed onto a detection plane, which spot is used to produce said pulsed measuring signal. Further, the two light beams are preferably scanned by the same scanning means which comprises a parallel sided block of regular cross-section which is rotated about an axis through its centre parallel to its sides and which refracts the beams directed normal to its axis of rotation.
Inventors
- 👤 G Parkinson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 14:52
CPC Classifications
G; G01; G01B; G01B11/00; G01B11/08; G01B11/10; G01B11/105; G01B11/24
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
273 words
A profile gauge comprising a light source which produces a first beam of light; scanning means which scans said first beam of light in a parallel manner across a measuring space in which an object to be measured is to be disposed; first light deTecting means which is disposed to receive said first beam when it is not interrupted by an object in said measuring space and which produces a profile signal which varies in amplitude with the intensity of said beam; a monochromatic light source which produces a second beam of light; a first diffraction grating through which said second beam passes in a fixed direction and which diffracts said second beam; scanning means which is disposed in the path of said second beam from the first diffraction grating and which scans said second beam in a parallel manner in synchronism with said first beam; a second diffraction grating which is disposed in the path of said second scanned beam of light so that it is scanned thereby and further diffracts said second beam so as to produce a diffraction spot in a detection plane; second light detecting means which is disposed to receive the light from said second beam forming said diffraction spot and which produces a corresponding pulsed measuring signal continuously during scanning of the second beam, each pulse produced corresponding to a scanning movement of the second beam by one line spacing intervals across said second grating; gating means which gates said pulsed measuring signal under the control of said profile signal; and counting means which counts the pulses in said gated measuring signal and produces corresponding width measurements.
Claim 2
Dependent Claim
273 words
A profile gauge comprising a light source which produces a first beam of light; scanning means which scans said first beam of light in a parallel manner across a measuring space in which an object to be measured is to be disposed; first light deTecting means which is disposed to receive said first beam when it is not interrupted by an object in said measuring space and which produces a profile signal which varies in amplitude with the intensity of said beam; a monochromatic light source which produces a second beam of light; a first diffraction grating through which said second beam passes in a fixed direction and which diffracts said second beam; scanning means which is disposed in the path of said second beam from the first diffraction grating and which scans said second beam in a parallel manner in synchronism with said first beam; a second diffraction grating which is disposed in the path of said second scanned beam of light so that it is scanned thereby and further diffracts said second beam so as to produce a diffraction spot in a detection plane; second light detecting means which is disposed to receive the light from said second beam forming said diffraction spot and which produces a corresponding pulsed measuring signal continuously during scanning of the second beam, each pulse produced corresponding to a scanning movement of the second beam by one line spacing intervals across said second grating; gating means which gates said pulsed measuring signal under the control of said profile signal; and counting means which counts the pulses in said gated measuring signal and produces corresponding width measurements.
Claim 3
Dependent Claim
61 words
A gauge as claimed in claim 1 in which the periodic line spacing interval of both gratings is the same and the width of the beam is such that it covers a plurality of line intervals on both gratings, the beam transmitted by said additional grating remaining effectively as a single beam comprising several component diffracted beams between the two gratings.
Claim 4
Dependent Claim
31 words
A gauge as claimed in claim 2 in which the two gratings and the lines ruled on them are parallel to one another, and the beam is incident on them normally.
Claim 5
Dependent Claim
19 words
A gauge as claimed in claim 1 in which the two beams are scanned by the same scanning means.
Claim 6
Dependent Claim
71 words
A gauge as claimed in claim 4, in which the scanning means comprises a parallel sided block of light refracting material of regular polygonal cross-section through which both light beams pass, the block being mounted to rotate about an axis through the centre of the block parallel to its sides and the light beams being directed at the sides of the block along fixed axes normally to the axis of rotation.
Claim 7
Dependent Claim
27 words
A gauge as claimed in claim 5 in which the block has a square cross-section and the two beams are directed at right angles to one another.
Claim 8
Dependent Claim
51 words
A gauge as claimed in claim 5 in which the first beam if it is not interrupted by an object is reflected by a mirror after traversing said measuring space and retraces its path back through said block to said first light detecting means which takes the form of a photo-detector.
Claim 9
Dependent Claim
26 words
A gauge as claimed in claim 1 which includes focusing means that focuses said first beam in the profile plane through an object to be measured.
Claim 10
Dependent Claim
22 words
A gauge as claimed in claim 1 in which both of said light sources are provided by a single monochromatic light source.
Claim 11
Dependent Claim
20 words
A gauge as claimed in claim 1 in which the pulsed measuring signal is increased in frequency by electronic means.
Claim 12
Dependent Claim
118 words
A gauge as claimed in claim 10 in which said electronic means comprises an adjustable frequency oscillator, a frequency divider unit which receives the signal from the oscillator and divides it by a preset factor, and comparator means which receives the signal from the divider unit and the pulsed measuring signal and which produces an output signal which is dependent on the difference in frequency between the two input signals and which adjusts the frequency of the oscillator so that it is higher by said preset factor than the frequency of the pulsed measuring signal, the output signal from the oscillator being used as the new higher frequency pulsed measuring signal which is supplied to said gating means.
Claim 13
Dependent Claim
119 words
A gauge as claimed in claim 1 which further includes an oPtical beam splitting device in the path of the first beam between the scanning means and the measuring space, which device is adapted to split the beam into two parallel beams which scan the measuring space in unison with the incident beam, said first light detecting means comprising a separate lens and detector associated with each beam so that the respective lens focuses the beam onto the respective detector after it has traversed the measuring space, the two detectors thereby producing separate signals which indicate the presence of a respective edge of the object and which are fed to means which processes them to form said profile signal.
Claim 14
Dependent Claim
65 words
A gauge comprising two gauges as claimed in claim 1 which operate sinultaneously to measure the width of an object; and means to average the measurements which they make; the scanning means which scans the first beam in each gauge being adapted so that the two beams are parallel and scan in unison but with the beams always moving in opposite directions to one another.
Claim 15
Dependent Claim
66 words
A gauge as claimed in claim 13 in which the two beams in each gauge are scanned by the same scanning means which takes the form of a parallel sided block of light refracting material of regular polygonal cross-section and which is rotated about an axis through its centre parallel to its sides, the two blocks being rotated at the same speed but in opposite directions.
Claim 16
Dependent Claim
261 words
A profile gauge comprising light source means which produces first and second beams of light; scanning means in the form of a parallel sided block of light refracting material of regular cross section through which both beams pass, the block being mounted to rotate about an axis through the centre of the block parallel to its sides and the beams being directed at the sides of the block along fixed axes normal to the axis of rotation so that each beam is scanned in a parallel manner and both beams are scanned in synchronism, the first beam scanning across the measuring space in which an object to be measured is to be disposed; first light detecting means which is disposed to receive said first beam when it is not interrupted by an object in said measuring space and which produces a profile signal which varies in amplitude with the intensity of said beam; a diffraction grating which is disposed in the path of said second scanned beam of light so it is scanned thereby; second light detecting means which is disposed to receive light from said second beam after it has passed through said grating and which produces a pulse measuring signal continuously during scanning of the second beam, each pulse produced corresponding to a scanning movement of the second beam by one line spacing interval across the grating; gating means which gates said pulsed measuring signal under the control of said profile signal; and counting means which count the pulses in said gated measuring signal and produces corresponding width measurements.
Claim 17
Dependent Claim
261 words
A profile gauge comprising light source means which produces first and second beams of light; scanning means in the form of a parallel sided block of light refracting material of regular cross section through which both beams pass, the block being mounted to rotate about an axis through the centre of the block parallel to its sides and the beams being directed at the sides of the block along fixed axes normal to the axis of rotation so that each beam is scanned in a parallel manner and both beams are scanned in synchronism, the first beam scanning across the measuring space in which an object to be measured is to be disposed; first light detecting means which is disposed to receive said first beam when it is not interrupted by an object in said measuring space and which produces a profile signal which varies in amplitude with the intensity of said beam; a diffraction grating which is disposed in the path of said second scanned beam of light so it is scanned thereby; second light detecting means which is disposed to receive light from said second beam after it has passed through said grating and which produces a pulse measuring signal continuously during scanning of the second beam, each pulse produced corresponding to a scanning movement of the second beam by one line spacing interval across the grating; gating means which gates said pulsed measuring signal under the control of said profile signal; and counting means which count the pulses in said gated measuring signal and produces corresponding width measurements.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-08-12 | 1978-02-11 | 1978-08-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-08-12 | 1982-02-11 | 1982-08-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-08-12 | 1986-02-11 | 1986-08-13 | $7700.00 | Window Closed / Lapsed |