Patent US3764741A successfully refreshed from Google Patents.
US3764741A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Lead screw control for linear drive system
Assignee: UNITED PRESS INT Inc
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Filing: 1970-11-27
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Granted: 1973-10-09
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Expires: 1990-11-27
Abstract
Abstract A lead control of a linear drive system particularly adapted to a drum type facsimile scanner is provided. The scanner head assembly is mounted for free movement on rails extending parallel to the axis of the drum. A half nut is affixed to the head assembly and engages a lead screw which is driven to linearly advance the head assembly. The lead screw is pivotally connected to the machine frame for rotation about an offset axis parallel to the axis of the lead screw. A friction clutch is provided between the lead screw and the machine frame and the reaction force produced by this clutch when the lead screw is rotated in a first direction causes the lead screw to pivot to bring the lead screw into meshing engagement with the half nut to effect a linear motion to the lead assembly relative to the drum. Rotation of the lead screw in the opposite direction produces an opposite reactive force through the friction clutch to pivot the lead screw away from the half nut, and terminate the linear motion of the head assembly.
Inventors
- 👤 J Long
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 21:55
CPC Classifications
H; H04; H04N; H04N1/00; H04N1/04; H04N1/06; H04N1/0671; H04N1/0678; G; G01; G01R; G01R17/00
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
119 words
A lead screw control assembly for a linear drive system which comprises a head assembly, means to support the assembly for linear movement in a fixed path, a half nut mounted in fixed relation to the assembly, an elongated lead screw with its axis extending parallel to said fixed path, support means for said screw to effect movement thereof laterally in parallel relation to said path to and from cooperative meshed engagement with said half nut, motor means rotatably drive said lead screw, and means acting on said support means for biasing said screw into engagement with said nut when rotated in one direction and out of engagement with said nut when said screw''s rotation is reversed or stopped.
Claim 2
Dependent Claim
119 words
A lead screw control assembly for a linear drive system which comprises a head assembly, means to support the assembly for linear movement in a fixed path, a half nut mounted in fixed relation to the assembly, an elongated lead screw with its axis extending parallel to said fixed path, support means for said screw to effect movement thereof laterally in parallel relation to said path to and from cooperative meshed engagement with said half nut, motor means rotatably drive said lead screw, and means acting on said support means for biasing said screw into engagement with said nut when rotated in one direction and out of engagement with said nut when said screw''s rotation is reversed or stopped.
Claim 3
Dependent Claim
36 words
An assembly according to claim 1 which includes means to change the fixed position of the half nut with respect to the head assembly to expose another portion of the threads thereof to the lead screw.
Claim 4
Dependent Claim
31 words
A control assembly according to claim 1 where said support means for said screw includes a V-shaped notch receiving said screw therein to support said screw along the full length thereof.
Claim 5
Dependent Claim
20 words
A control assembly according to claim 3 which includes a friction resistant layer on the surfaces of said V-shaped notch.
Claim 6
Dependent Claim
125 words
A control assembly according to claim 1 where said motor means includes a pinion rotatably driven on a driving axis, said support means for said screw comprises a mounting bar rotatably mounted in alignment with the axis of said motor means, said mounting bar rotatably supportinG said lead screw in spaced parallel relation to the pivotal mounting thereof, a spur gear operatively affixed to said lead screw and engaging the pinion of the motor means, and said means responsive to the rotatable drive of said lead screw comprises a torque clutch cooperating with the mounting bar to limit the pivotal movement thereof to and from meshing relation of the screw with the half nut directly dependent upon the direction of rotation of the motor means.
Claim 7
Dependent Claim
86 words
An assembly according to claim 5 wherein said torque clutch comprises a split block, spring means to resiliently control the split opening therein, a pair of spaced holes through the split in the block, one end of the lead screw received in frictional engagement through one hole, and a fixed mounted pin operatively received through the other hole, said pin being of smaller diameter than said other hole whereby the play of said pin in the second hole limits the pivotal relation of the mounting bar.
Claim 8
Dependent Claim
57 words
A control assembly according to claim 1 for a facsimile apparatus which includes first means to define an initial position of said head assembly with respect to said means to support said assembly, said first means also returning said head assembly to said initial position whenever said lead screw is in unmeshed relation with said half nut.
Claim 9
Dependent Claim
31 words
An assembly according to claim 7 which includes a second means to provide a controlled braking to the head assembly upon its return to an initial position by said first means.
Claim 10
Dependent Claim
105 words
An assembly according to claim 8 where said first means is a wind up tension device fixedly mounted in spaced relation to said head assembly, a cord connecting the tension device to the head assembly whereby the device winds up upon movement of the assembly away therefrom by the action of the cord extending therebetween, and said second means is a centrifugally acting braking capstan assembly mounted to said head assembly, and means to actuate said capstan assembly dependent upon the linear speed of said head assembly to effect a braking action to said head assembly when the linear speed thereof exceeds a predetermined minimum.
Claim 11
Dependent Claim
195 words
A scanning head drive mechanism for a telephoto facsimile transmitter, comprising: a scanning head assembly; frame means supporting the head assembly for linear movement; a lead screw having its longitudinal axis parallel to the direction of linear movement of the scanning head assembly; a mounting bar having journals at its opposite ends for rotatably carrying the lead screw, the mounting bar being supported for rotation about an axis parallel to but offset from the longitudinal axis of the lead screw; means for rotatably driving the lead screw; a torque clutch connected to the lead screw and rotatable therewith through a fixed arc, the arrangement being such that further rotation of the lead screw produces a rotation of the lead screw and mounting bar through a limited arc about the axis of rotation of the mounting bar; and a half nut fixedly carried by the scanning head assembly and having meshing engagement with the lead screw when the lead screw and mounting bar are at one extreme of their limited arc of rotation, and being a non-meshing relation when the lead screw and mounting bar are at the other extreme of their limited arc of rotation.
Claim 12
Dependent Claim
195 words
A scanning head drive mechanism for a telephoto facsimile transmitter, comprising: a scanning head assembly; frame means supporting the head assembly for linear movement; a lead screw having its longitudinal axis parallel to the direction of linear movement of the scanning head assembly; a mounting bar having journals at its opposite ends for rotatably carrying the lead screw, the mounting bar being supported for rotation about an axis parallel to but offset from the longitudinal axis of the lead screw; means for rotatably driving the lead screw; a torque clutch connected to the lead screw and rotatable therewith through a fixed arc, the arrangement being such that further rotation of the lead screw produces a rotation of the lead screw and mounting bar through a limited arc about the axis of rotation of the mounting bar; and a half nut fixedly carried by the scanning head assembly and having meshing engagement with the lead screw when the lead screw and mounting bar are at one extreme of their limited arc of rotation, and being a non-meshing relation when the lead screw and mounting bar are at the other extreme of their limited arc of rotation.
Claim 13
Dependent Claim
33 words
The mechanism according to claim 10 wherein the mounting bar extends along at least the threaded portion of the lead screw and is provided with a groove receiving and supporting the lead screw.
Claim 14
Dependent Claim
53 words
The mechanism according to claim 11 which includes tension means to return the head assembly to an initial position whenever the lead screw and half-nut are in unmeshed relation, and brake assembly means to effect a controlled braking of said tension means during the return of said head assembly to its initial position.
References Cited (Backward Citations)
US2601236A
Cited
US3280251A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-10-08 | 1977-04-09 | 1977-10-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-10-08 | 1981-04-09 | 1981-10-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-10-08 | 1985-04-09 | 1985-10-09 | $7700.00 | Window Closed / Lapsed |