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US3753451A Expired / Lapsed US ⏱️ 0.0 years remaining

Let-off motion in loom

Assignee: Teijin Ltd
•
Filing: 1970-03-30
•
Granted: 1973-08-21
•
Expires: 1990-03-30
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Abstract

Abstract A warp let-off mechanism for a loom having a warp beam driven through a variable speed transmission and a backrest over which the warp runs, the backrest being movable in a direction for increasing and decreasing warp tension and being resiliently urged against warp tension in the tension increasing direction, the variable speed transmission having means for varying the speed thereof. The warp let-off mechanism is comprised of a first adjustment means comprising backrest coupling means coupled between the backrest and the means for varying the speed of the variable speed transmission and responsive to an increase or decrease in tension in the warp as the removal of the warp from the warp beam progresses for adjusting the position of the varying means to increase or decrease, respectively, the speed of the warp beam for reducing or increasing, respectively, the tension. A second adjustment means is coupled to the first adjustment means and is responsive to adjusting movement of the first adjusting means for adjusting the coupling between the coupling means and the varying means to return the backrest to its initial position while maintaining the varying means in its adjusted position.

Inventors

  • 👤 S Hosono
  • 👤 K Kida

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-03 14:10
CPC Classifications
D; D03; D03D; D03D49/00; D03D49/04; D03D49/06

Claims Analysis

Total Claims: 8
Claim 1
Independent Claim 186 words
In a loom having a warp beam driven through a variable speed transmission and a backrest over which the warp runs, the backrest being movable in a direction for increasing and decreasing warp tension and being resiliently urged against warp tension in the tension increasing direction, the variable speed transmission having means for varying the speed thereof, a warp let-off mechanism comprised of a first adjustment means comprising backrest coupling means coupled between said backrest and said means for varying the speed of said variable speed transmission and responsive to an increase or decrease in tension in the warp as the removal of the warp from the warp beam progresses for adjusting the position of said varying means to increase or decrease, respectively, the speed of the warp beam for reducing or increasing, respectively, the tension, and a second adjustment means coupled to said first adjustment means and responsive to adjusting movement of said first adjusting means for adjusting the coupling between said coupling means and said varying means to return the backrest to its initial position while maintaining said varying means in its adjusted position.
Claim 2
Dependent Claim 186 words
In a loom having a warp beam driven through a variable speed transmission and a backrest over which the warp runs, the backrest being movable in a direction for increasing and decreasing warp tension and being resiliently urged against warp tension in the tension increasing direction, the variable speed transmission having means for varying the speed thereof, a warp let-off mechanism comprised of a first adjustment means comprising backrest coupling means coupled between said backrest and said means for varying the speed of said variable speed transmission and responsive to an increase or decrease in tension in the warp as the removal of the warp from the warp beam progresses for adjusting the position of said varying means to increase or decrease, respectively, the speed of the warp beam for reducing or increasing, respectively, the tension, and a second adjustment means coupled to said first adjustment means and responsive to adjusting movement of said first adjusting means for adjusting the coupling between said coupling means and said varying means to return the backrest to its initial position while maintaining said varying means in its adjusted position.
Claim 3
Dependent Claim 235 words
In a loom having a warp beam driven through a variable speed transmission and a backrest over which the warp runs, the backrest being movable in a direction for increasing and decreasing the warp tension and being resiliently urged against warp tension in the tension increasing direction, the variable speed transmission having a lever for varying the speed thereof, a warp let-off mechanism comprised of a first adjustment means comprising a lever and rod means and a threaded shaft coupled to the backrest and a joint on said threaded shaft connected to said variable speed transmission lever, the variable speed transmission lever being moved to an adjusted position to increase or decrease the speed of the warp beam for reducing or increasing, respectfully, the warp tension in response to an increase or decrease, respectively, of warp tension as the removal of the warp from the warp beam progresses, and a second adjustment means comprising a shaft rotating means positioned adjacent said threaded shaft and coupled to said threaded shaft only when said threaded shaft moves in response to changed warp tension, and driving means coupled to said shaft rotating means for driving said shaft rotating means, said shaft rotating means rotating said threaded shaft in a direction to move said shaft relative to said joint to return the backrest to its initial position while maintaining said joint and said transmission lever at the adjusted position.
Claim 4
Dependent Claim 235 words
In a loom having a warp beam driven through a variable speed transmission and a backrest over which the warp runs, the backrest being movable in a direction for increasing and decreasing the warp tension and being resiliently urged against warp tension in the tension increasing direction, the variable speed transmission having a lever for varying the speed thereof, a warp let-off mechanism comprised of a first adjustment means comprising a lever and rod means and a threaded shaft coupled to the backrest and a joint on said threaded shaft connected to said variable speed transmission lever, the variable speed transmission lever being moved to an adjusted position to increase or decrease the speed of the warp beam for reducing or increasing, respectfully, the warp tension in response to an increase or decrease, respectively, of warp tension as the removal of the warp from the warp beam progresses, and a second adjustment means comprising a shaft rotating means positioned adjacent said threaded shaft and coupled to said threaded shaft only when said threaded shaft moves in response to changed warp tension, and driving means coupled to said shaft rotating means for driving said shaft rotating means, said shaft rotating means rotating said threaded shaft in a direction to move said shaft relative to said joint to return the backrest to its initial position while maintaining said joint and said transmission lever at the adjusted position.
Claim 5
Dependent Claim 69 words
A warp let-off mechanism as claimed in claim 2 in which said second adjustment means comprises ratchet wheel means on said threaded shaft and ratchet means positioned adjacent said shaft and spaced from said ratchet wheel means when the backrest is in the normal position and engaged with said ratchet wheel means when said backrest is displaced from the normal position due to a change in the warp tension.
Claim 6
Dependent Claim 48 words
A warp let-off mechanism as claimed in claim 3 in which said driving means coupled to said shaft rotating means comprises a lever means on which said ratchet means is mounted, and cam means driven by said transmission engaged with said lever means for oscillating said lever means.
Claim 7
Dependent Claim 73 words
A warp let-off mechanism as claimed in claim 2 in which said second adjustment means comprises bevel gear means on said threaded shaft and further bevel gear means positioned adjacent said shaft and spaced from said firstmentioned bevel gear means when the backrest is in the normal position and engaged with said firstmentioned bevel gear means when said backrest is displaced from the normal position due to a change in the warp tension.
Claim 8
Dependent Claim 35 words
A warp let-off mechanism as claimed in claim 5 in which said driving means coupled to said shaft rotating means comprises a drive shaft coupled to said further bevel gear and driven by said transmission.

References Cited (Backward Citations)

US1729130A Cited
US2435437A Cited
US2681080A Cited
US2819734A Cited
DE964432C Cited
US2888955A Cited
US3308854A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1976-08-20 1977-02-19 1977-08-21 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1980-08-20 1981-02-19 1981-08-21 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1984-08-20 1985-02-19 1985-08-21 $7700.00 Window Closed / Lapsed

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