US3659437A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Knitting machine defective needle detector
Assignee: RJ Reynolds Tobacco Co
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Filing: 1969-07-25
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Granted: 1972-05-02
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Expires: 1989-07-25
Abstract
Abstract A circular knitting machine, comprising a device for detecting defective needles by detecting the absence of a needle hook from its proper place. The device is placed at a locality adjacent the circular path of needle travel, and the needles are raised by a cam so that the hook of every good and properly positioned needle intercepts a collimated bead of radiant energy. The beam is not intercepted properly by a needle which has a broken, bent or otherwise defective hook or which, because of broken butt or other causes, has not been raised properly. The detector is connected to an alarm and may also be connected to a conventional stop motion device. Alternatively, a small magnet mounted on a piezoelectric crystal or magnetic pickup is positioned in the proximity of the hooks of the needles which have been raised by the cam referred to above. The magnet will be deflected by each passing needle of proper constitution and attitude in substantially the same manner, but will be deflected differently by a defective needle.
Inventors
- 👤 Colin S Mcarthur
- 👤 Benny L Hester
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 20:31
CPC Classifications
D; D04; D04B; D04B35/00; D04B35/10; D04B35/18
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
105 words
Apparatus for detecting defective needles in a knitting machine having a regular array of needles, comprising: a. means for generating a beam of radiant energy; b. means for producing relative motion between the beam and the needles so that the needles successively intersect and at least partially block the beam; c. means for detecting the beam, said means located on the opposite side of the intersecting needles from the generating means, said detecting means producing a signal varying as a function of the radiant energy impinging thereon; and d. means responsive to an irregular variation in said signal for indicating that a needle is defective.
Claim 2
Dependent Claim
105 words
Apparatus for detecting defective needles in a knitting machine having a regular array of needles, comprising: a. means for generating a beam of radiant energy; b. means for producing relative motion between the beam and the needles so that the needles successively intersect and at least partially block the beam; c. means for detecting the beam, said means located on the opposite side of the intersecting needles from the generating means, said detecting means producing a signal varying as a function of the radiant energy impinging thereon; and d. means responsive to an irregular variation in said signal for indicating that a needle is defective.
Claim 3
Dependent Claim
94 words
Apparatus as in claim 1 including: d. means for discriminating between, on the one hand, a first signal prodUced by the detecting means while said beam is intersected by a needle which is in its proper position, and, on the other hand, a second signal produced by the detecting means while said beam is directed toward the proper position of a needle which is not in its proper position; and e. an alarm and a stop-motion device, each energizable by said discriminating means upon the detection by said discriminating means of said second signal.
Claim 4
Dependent Claim
73 words
Apparatus as in claim 1 wherein said generating and said detecting means are positioned for directing the beam of radiant energy along a path intersected by the needle hoods, said detecting means producing a first type signal to correspond to a needle which has its hook in the normal position while intersecting the beam and producing a second type signal to correspond to a needle whose hook is absent from its normal position.
Claim 5
Dependent Claim
80 words
Apparatus as in claim 1 wherein said needles are in a circular array of needles, and including: a. means for rotating the needle array with respect to the beam and means for raising needles successively as the circular array of needles is rotated; and wherein b. the generating and the detecting means are positioned for directing the beam of radiant energy along a path intersected by the hooks of the needles as they are raised successively by said raising means.
Claim 6
Dependent Claim
37 words
Apparatus as in claim 1 wherein means is provided for collimating the beam of radiant energy to a width less than the width of a needle at the point where the beam is intersected by the needles.
Claim 7
Dependent Claim
37 words
Apparatus as in claim 1 wherein said array of needles is a circular array and including means for supporting said generating means and said detecting means entirely outside the space defined by said circular array of needles.
Claim 8
Dependent Claim
19 words
Apparatus as in claim 6 wherein said beam is parallel to a tangent of said circular array of needles.
Claim 9
Dependent Claim
176 words
Circular knitting apparatus, including a stationary support, a circularly disposed array of vertically movable needles of magnetic material, each needle having a hook at its top end, and means for rotating said array of needles; the improvement comprising: a. magnet means for generating a magnetic field intercepting the array of needles, said magnet means positioned near the normal path of travel of the needles as they are rotated; b. a transducer for converting mechanical stresses to electrical energy, said transducer being rigidly connected to said magnet means; and c. means connected to said stationary support for supporting the transducer, whereby said magnet means is affected in substantially the same manner by each passing needle which is in its proper position and is affected in a different manner by a passing needle which is not in its proper position, and whereby said transducer produces a first electrical signal in response to passing needles which are in their proper positions and a second, distinctively different electrical signal in response to needles which are not in their proper positions.
Claim 10
Dependent Claim
176 words
Circular knitting apparatus, including a stationary support, a circularly disposed array of vertically movable needles of magnetic material, each needle having a hook at its top end, and means for rotating said array of needles; the improvement comprising: a. magnet means for generating a magnetic field intercepting the array of needles, said magnet means positioned near the normal path of travel of the needles as they are rotated; b. a transducer for converting mechanical stresses to electrical energy, said transducer being rigidly connected to said magnet means; and c. means connected to said stationary support for supporting the transducer, whereby said magnet means is affected in substantially the same manner by each passing needle which is in its proper position and is affected in a different manner by a passing needle which is not in its proper position, and whereby said transducer produces a first electrical signal in response to passing needles which are in their proper positions and a second, distinctively different electrical signal in response to needles which are not in their proper positions.
Claim 11
Dependent Claim
58 words
Apparatus as in claim 8 wherein said magnet means is positioned adjacent the normal path of travel of the needle hooks, whereby said transducer produces a first electrical signal to correspond to needles which have their hooks in the proper position, and a second electrical signal to correspond to needles whose hooks are absent from their normal positions.
Claim 12
Dependent Claim
52 words
Apparatus as in claim 8 including: a. means for raising the needles as they approach the magnetic means; and b. means for positioning said magnet means adjacent the normal path of the hooks of the raised needles, whereby needle defects affecting the ability of a hook to be properly raised are detected.
Claim 13
Dependent Claim
25 words
Apparatus as in claim 8, including demagnetizing means positioned along the path of the needles past said magnet for removing residual magnetism from the needles.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-05-02 | 1975-11-01 | 1976-05-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-05-02 | 1979-11-01 | 1980-05-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-05-02 | 1983-11-01 | 1984-05-02 | $7700.00 | Window Closed / Lapsed |