Patent US3908920A successfully refreshed from Google Patents.
US3908920A
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Process and apparatus for maintaining constant thread tension
Assignee: FMN Schuster GmbH and Co KG
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Filing: 1973-07-17
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Granted: 1975-09-30
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Expires: 1993-07-17
Abstract
Abstract The process and an apparatus for maintaining a constant thread tension is disclosed for feeding a thread to a processing textile machine. A constant air stream is blown against the thread to form a thread loop having an apex. The displacement of the loop apex resulting from thread speed fluctuations is monitored. The amount of displacement of the loop apex is used as an adjusting value for the regulation of the thread supply. The blowing operation is effected within an open ended elongated channel. Means providing at least two light barriers which extend in a direction across the path of movement for the apex of the thread loop within the air channel are used to effectuate the monitoring step. Means associated with the light barriers are used to regulate the supply of thread along its path of movement through the air channel to the processing textile machine.
Inventors
- 👤 Peter Hermanns
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 13:04
CPC Classifications
B; B65; B65H; B65H59/00; B65H59/10; B65H59/105; B65H59/38; B65H59/384; B65H59/385; B65H2701/00; B65H2701/30; B65H2701/31
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
245 words
An apparatus for maintaining a constant thread tension while feeding a thread to a processing textile machine comprising: a. housing means forming an open ended, elongated air channel, b. means for moving a thread along a path transversely across the air channel at one end thereof, c. means adjacent the channel for blowing a fluid stream against the thread to form a thread loop having an apex which moves within the air channel, d. at least two light barrier means disposed at laterally spaced locations with respect to each other and extending in a direction across the path of movement for the apex of the thread loop within the air channel, e. each light barrier means defining a signal point within the air channel where an electrical signal is generated by the thread loop as it passes by a signal point, f. the electrical pulse signals generated by the thread loop at both signal points being transmitted to separate inputs of a bistable element that stores in each case the last pulse signal up to the receipt of the next signal, g. the output of the bistable element being connected with a circuit and at the output of said circuit there is generated a voltage change dictated by the pulse sequence at the bistable element due to the pulse scanning ratio, and h. means responsive to the electrical signals generated at the light barriers for regulating the supply of thread along its path of movement.
Claim 2
Independent Claim
245 words
An apparatus for maintaining a constant thread tension while feeding a thread to a processing textile machine comprising: a. housing means forming an open ended, elongated air channel, b. means for moving a thread along a path transversely across the air channel at one end thereof, c. means adjacent the channel for blowing a fluid stream against the thread to form a thread loop having an apex which moves within the air channel, d. at least two light barrier means disposed at laterally spaced locations with respect to each other and extending in a direction across the path of movement for the apex of the thread loop within the air channel, e. each light barrier means defining a signal point within the air channel where an electrical signal is generated by the thread loop as it passes by a signal point, f. the electrical pulse signals generated by the thread loop at both signal points being transmitted to separate inputs of a bistable element that stores in each case the last pulse signal up to the receipt of the next signal, g. the output of the bistable element being connected with a circuit and at the output of said circuit there is generated a voltage change dictated by the pulse sequence at the bistable element due to the pulse scanning ratio, and h. means responsive to the electrical signals generated at the light barriers for regulating the supply of thread along its path of movement.
Claim 3
Dependent Claim
17 words
An apparatus as defined in claim 1 wherein means is provided for oscillating the light barrier means.
Claim 4
Dependent Claim
46 words
An apparatus as defined in claim 1 wherein the circuit comprises an integration step with a condenser changeable via a first transistor and a resistance and dischargeable by a second transistor and a resistance, both said transistors being controlled by the output of the bistable element.
Claim 5
Dependent Claim
86 words
An apparatus as defined in claim 1 wherein the processing textile machine has a take-up means driven by an electrical drive motor for taking up the thread moving along said path and means providing a signal corresponding to the speed of the take-up means, the output signal of the integration step and the signal corresponding to the speed of the take-up means are provided at the entries of a differential amplifier which, if necessary through a power amplifer, controls the drive motor of the take-up means.
Claim 6
Dependent Claim
33 words
An apparatus as defined in claim 1 wherein the charging time constant and the discharging time constant of the integration step is great relative to a cycle of movement of a setting device.
Claim 7
Dependent Claim
23 words
An apparatus as defined in claim 5 wherein the charging time constant and the discharging time constant of the integration step are equal.
Claim 8
Dependent Claim
50 words
An apparatus as defined in claim 1 wherein means are provided to effect oscillating movement of the light barrier means, and the charging time constant and the discharging time constant of the integration step is great relative to a cycle of movement of the oscillating movement of the light barriers.
Claim 9
Dependent Claim
23 words
An apparatus as defined in claim 7 wherein the charging time constant and the discharging time constant of the integration step are equal.
Claim 10
Dependent Claim
88 words
An apparatus as defined in claim 1 wherein said two light barrier means constitute primary light barriers and there are supplemental light barriers disposed outside the region of the primary light barriers, the supplemental light barriers are electrically connected in the control circuit to generate supplemental electrical signals when the length of the thread loop passes by a signal point established by the supplemental light barriers, and second means responsive to said supplemental electrical signals are provided for regulating the supply of thread along its path of movement.
Claim 11
Independent Claim
149 words
An apparatus for maintaining a constant thread tension while feeding a thread to a processIng textile machine comprising: a. housing means forming an open ended, elongated air channel, b. means for moving a thread along a path transversely across the air channel at one end thereof, c. means adjacent the air channel for blowing a fluid stream against the thread to form a thread loop having an apex which moves within the air channel, d. at least two light barrier means disposed at laterally spaced locations with respect to each other along the air channel and extending in a direction across the path of movement for the apex of the thread loop within the air channels, e. means for oscillating the light barrier means, and f. means responsive to the electrical signals generated at the light barrier means for regulating the supply of thread along its path of movement.
Claim 12
Independent Claim
149 words
An apparatus for maintaining a constant thread tension while feeding a thread to a processIng textile machine comprising: a. housing means forming an open ended, elongated air channel, b. means for moving a thread along a path transversely across the air channel at one end thereof, c. means adjacent the air channel for blowing a fluid stream against the thread to form a thread loop having an apex which moves within the air channel, d. at least two light barrier means disposed at laterally spaced locations with respect to each other along the air channel and extending in a direction across the path of movement for the apex of the thread loop within the air channels, e. means for oscillating the light barrier means, and f. means responsive to the electrical signals generated at the light barrier means for regulating the supply of thread along its path of movement.
Claim 13
Independent Claim
252 words
An apparatus for maintaining a constant thread tension while feeding a thread to a processing textile machine comprising: a. housing means forming an open ended, elongated air channel, b. means for moving a thread along a path transversely across the air channel at one end thereof, c. means adjacent the air channel for blowing a fluid stream against the thread to form a thread loop having an apex which moves within the air channel, d. at least two light barrier means disposed at laterally spaced locations with respect to each other along the air channel and extending in a direction across the path of movement for the apex of the thread loop within the air channel, e. each light barrier means defining a signal point within the air channel where an electrical signal is generated by the thread loop as it passes by a signal point, f. the electrical pulse signals generated by the thread loop at both signal points are being transmitted to separate inputs of a trigger step means storing in each case the last pulse signal up to the receipt of the next signal, g. the output of the trigger step being connected with a circuit and the output of the said circuit there is generated a voltage change dictated by the pulse sequence at the trigger step due to the pulse scanning ratio, and h. means responsive to the electrical signals generated at the light barrier means for regulating the supply of thread along its path of movement.
Claim 14
Independent Claim
252 words
An apparatus for maintaining a constant thread tension while feeding a thread to a processing textile machine comprising: a. housing means forming an open ended, elongated air channel, b. means for moving a thread along a path transversely across the air channel at one end thereof, c. means adjacent the air channel for blowing a fluid stream against the thread to form a thread loop having an apex which moves within the air channel, d. at least two light barrier means disposed at laterally spaced locations with respect to each other along the air channel and extending in a direction across the path of movement for the apex of the thread loop within the air channel, e. each light barrier means defining a signal point within the air channel where an electrical signal is generated by the thread loop as it passes by a signal point, f. the electrical pulse signals generated by the thread loop at both signal points are being transmitted to separate inputs of a trigger step means storing in each case the last pulse signal up to the receipt of the next signal, g. the output of the trigger step being connected with a circuit and the output of the said circuit there is generated a voltage change dictated by the pulse sequence at the trigger step due to the pulse scanning ratio, and h. means responsive to the electrical signals generated at the light barrier means for regulating the supply of thread along its path of movement.
Claim 15
Dependent Claim
51 words
An apparatus as defined in claim 11 wherein the circuit comprises an integration step with a condenser chargeable via a first electronic switch and a resistance and is dischargable via a second electronic switch and a resistance, both said electronic switches being controlled by the output of the trigger step means.
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) | 1978-09-29 | 1979-03-31 | 1979-09-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-09-29 | 1983-03-31 | 1983-09-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-09-29 | 1987-03-31 | 1987-09-30 | $7700.00 | Window Closed / Lapsed |