US3741663A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Hole detector (for moving web)
Assignee: NEVINS MACHINERY CORP
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Filing: 1972-03-27
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Granted: 1973-06-26
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Expires: 1992-03-27
Abstract
Abstract A hole detector for a moving web of translucent or opaque material capable of indicating the presence of relatively small holes at high web speeds. An elongate light source and light sensing trough are spaced on opposite sides of the moving web and extend transversely across the portion of the web to be monitored. Light sensors are spaced along the bottom wall of the trough remote from the web for receiving direct light inputs through web holes passing over the open top of the trough. The light sensors are nonresponsive to spurious light inputs and each sensor responds negligibly, at most, to passage of a web hole over neighboring sensors, while permitting a space to be maintained between the web and the trough to prevent abrasion damage to the web being monitored despite normal flexing of the web. The trough depth substantially exceeds its width. The sidewalls of the trough diverge at a very shallow included angle from a bottom wall and terminate in shorter, parallel upper sidewalls. The sensors are separately compartmented within the trough, the walls of each compartment being substantially fully light absorptive. The trough has externally extending flanges at the top thereof for preventing light reflected from the undersurface of the web from reaching the sensors. The device is adapted to handle webs of decreased widths and includes devices for indicating the presence and locations of holes in the web.
Inventors
- 👤 M Nevins
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 19:43
CPC Classifications
G; G01; G01N; G01N21/00; G01N21/84; G01N21/88; G01N21/89; G01N21/892; G01N21/894
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
257 words
A hole detector for a moving web having a light source on one side thereof, comprising in combination: an elongate trough having a depth substantially exceeding its width, said trough being substantially V-shaped in crosssection and having opposed longitudinal sidewalls diverging at a narrow angle from a narrow longitudinal bottom wall and fixedly carrying a substantially transparent covering plate; a plurality of pairs of substantially triangular barrier walls distributed along the length of the trough, the barrier walls of each said pair extending divergently from said bottom wall between and in contact with the sidewall, each of said barrier wall pair defining a separated substantially pyramidal compartment opening at its larger end toward the plate, the opposed surfaces of the wall of each of said compartment being light absorptive and nonreflecting; a light sensor at the bottom wall of each compartment oriented for receiving direct light entering said compartment through said plate; support means locating said trough on the opposite side of said web and with said plate in close spaced, substantially parallel relation to said web, said trough extending transversely across said web so that light transmitted through a hole in said web and through said plate will strike one of said sensors; shielding means on said trough adjacent said plate and cooperating with said web for preventing light inputs other than through web holes from entering said trough at an angle to strike said sensors; indicating means responsive to actuation of said sensors by light for indicating the presence of a hole in said web.
Claim 2
Dependent Claim
257 words
A hole detector for a moving web having a light source on one side thereof, comprising in combination: an elongate trough having a depth substantially exceeding its width, said trough being substantially V-shaped in crosssection and having opposed longitudinal sidewalls diverging at a narrow angle from a narrow longitudinal bottom wall and fixedly carrying a substantially transparent covering plate; a plurality of pairs of substantially triangular barrier walls distributed along the length of the trough, the barrier walls of each said pair extending divergently from said bottom wall between and in contact with the sidewall, each of said barrier wall pair defining a separated substantially pyramidal compartment opening at its larger end toward the plate, the opposed surfaces of the wall of each of said compartment being light absorptive and nonreflecting; a light sensor at the bottom wall of each compartment oriented for receiving direct light entering said compartment through said plate; support means locating said trough on the opposite side of said web and with said plate in close spaced, substantially parallel relation to said web, said trough extending transversely across said web so that light transmitted through a hole in said web and through said plate will strike one of said sensors; shielding means on said trough adjacent said plate and cooperating with said web for preventing light inputs other than through web holes from entering said trough at an angle to strike said sensors; indicating means responsive to actuation of said sensors by light for indicating the presence of a hole in said web.
Claim 3
Dependent Claim
67 words
The device of claim 1, in which said indicating means includes a plurality of amplifiers connected to corresponding ones of said light sensors, a Control circuit connected to the output of each amplifier and a plurality of output devices associated with each said control circuit for indicating the presence of a hole in a width segment of the web corresponding to an actuated one of said sensors.
Claim 4
Dependent Claim
53 words
The device of claim 2, including OR gate means having a plurality of inputs each connected to one of said control circuits and an output terminal, recorder means actuable by the output of said OR gate means for making a visual recording of the occurrence in time of holes in the moving web.
Claim 5
Dependent Claim
76 words
The device of claim 2, in which said control circuit includes an instantaneous lamp, means for actuating same for substantially the duration of passage of a hole in said web across said trough, a memory lamp, means for actuating said memory lamp in response to the passage of a hole in said web across said trough and for holding said memory lamp in an on condition thereafter and manually actuatable means for de-energizing said memory lamp.
Claim 6
Dependent Claim
127 words
The device of claim 2, in which said control circuit includes an actuator responsive to energization of a corresponding sensor and capable of remaining actuated for a preselected time duration beginning in preselected time relation with the energization of said sensor, marking means opposed to the face of the web and extending thereacross, said marking means including a plurality of marking units which correspond in alignment along the web with ones of said sensors, each marking unit being capable of applying an elongated visible mark to the web in the transverse segment of the web corresponding to a hole sensed by the corresponding sensor and extending longitudinally of the web on both sides of said hole for visually indicating the presence of a hole in the web.
Claim 7
Dependent Claim
74 words
The device according to claim 5, in which said marking means includes a marking fluid reservoir supported in fixed relation to the trough and adjacent the web downstream of said trough, said marking units each comprising a fluid applicator pivotally mounted with respect to said reservoir and responsive to the corresponding actuator means for contacting the opposed face of the web, each said applicator being supplied marking fluid by means connected to said reservoir.
Claim 8
Dependent Claim
147 words
The device of claim 1, in which said indicating means comprises a chart recorder arranged for recording over a period of time holes detected in the moving web, a plurality each of instantaneous warning lights, memory lights and web marking units, each of said lights and marking units being associated with at least one of said sensors, said marking devices each being located adjacent the web and in longitudinally aligned relation with and downstream of their corresponding sensor, said lights being arranged in distributed relation across the web at a station along the web spaced from said trough and downstream thereof, said lights being aligned longitudinally of the web with their corresponding sensor whereby ignition of one of said lights indicates a hole in the corresponding segment of the web located adjacent thereto, and circuitry connecting said lights and marking devices and said recorder with said sensors.
Claim 9
Dependent Claim
84 words
The device of claim 1, in which said shielding means comprises a flange extending around the periphery of said trough and at least extending the length of the sidewalls of said trough and located in contacting and underlying supporting relation with said plate, the width of the flanges being at least half the width of the trough for preventing spurious light inputs from below the trough from extending therepast and being reflected by the web into the trough in alignment with the light sensors.
Claim 10
Dependent Claim
134 words
The device of claim 1, in which said shielding means includes a light shield at each end of said trough slidable along the length of said trough atop said plate, each said shield having substantially C-shaped portion for securing same for sliding motion along said plate and further having a first upwardly and outwardly angled wall and a second substaNtially horizontal and inwardly extending wall atop said first wall, said first and second walls of said light shields defining opposed pockets for receiving the edge portions of said web, each said edge portion of said web being located in spaced relation to the adjacent first and second walls but overlapping both sidewalls so as to prevent spurious light inputs into said trough from the ends thereof by passage between said plate and said web.
Claim 11
Dependent Claim
89 words
The device of claim 9, in which the shield means further includes substantially coplanar flanges surrounding said trough and lying at the free longitudinal edges of said sidewalls for snugly contacting said plate in underlying relation therewith, said flanges being provided with curved, thickened outer edge portions, the C-shaped portions of said light shields folding over the thickened flange outer edge portions, said C-shaped portions including spaced slots defining resilient fingers which grip said flange outer edges for preventing unintended shifting of said light shields longitudinally of said trough.
Claim 12
Dependent Claim
52 words
The device of claim 1, in which said support means includes a base portion fixed with respect to the path of the web and a movable portion fixed to the trough for allowing shifting of said trough out of adjacency with said web to facilitate web threading and access to said sensors.
Claim 13
Dependent Claim
161 words
The device of claim 1, in which said sidewalls of said trough comprise an angled bottom portion extending from said bottom wall and substantially parallel upper portions extending from said lower portions to adjacency with said plate, said angled lower portions being of height approximating twice that of said upper portions, said barrier walls each including substantially triangular shaped lower portions joined at the base edges thereof substantially in a plane passing through the line of joining of the upper and lower sidewalls, said barrier walls each further including an upstanding substantially rectangular upper barrier wall portion extending integrally from the base edge of one of said triangular portions substantially to said plate, said upper barrier wall portion being equally angled with respect to both of the adjacent lower barrier wall portions. Said trough further having end walls shaped to conform to the cross-sectional configuration of said trough and having one lower barrier portion angling inboard therefrom toward said bottom wall.
Claim 14
Dependent Claim
79 words
The device of claim 1, including a plurality of conductors connected to the light sensors of each of said compartments and defining a cable extending adjacent and outside of the bottom wall of said trough and further including a hollow cable housing fixed to the sidewalls of said trough and in spaced surrounding relationship to the exterior face of the bottom wall of said trough for enclosing said cable, said cable exiting from one end of said cable enclosure.
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) | 1976-06-25 | 1976-12-25 | 1977-06-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-06-25 | 1980-12-25 | 1981-06-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-06-25 | 1984-12-25 | 1985-06-26 | $7700.00 | Window Closed / Lapsed |