Intermittent motion device for high-speed rotating print drums

Claim 2

A printer comprising rotatable input means including a torsion shaft having first and second connection areas thereon; rotating means for rotating said input means at a substantially constant velocity; first and second printer drums secured to said first and second connection areas respectively, said drums having printing characters thereon; and magnetically operated exciter means including a first exciter located near one end of said torsion shaft and a second exciter located near the remaining end thereof; said exciters being adjusted to operate 180* out of phase with each other; each said exciter acting on its associated end of the torsion shaft to retard its rotation as the torsion shaft is rotated by said rotating means to cause said drums to oscillate in opposed relationship to each other at substantially the resonant frequency of said input means and drums to produce a dwell in the rotational movement of each drum for a cycle of oscillation, with the first printer drum experiencing any one of said dwells at a time when the second printer drum is rotating at substantially twice the velocity of said input means; said rotating means including an input shaft of predetermined flexibility being connected to one end of said torsion shaft to rotate it.

Claim 3

A printer comprising rotatable input means including a torsion shaft having first, second, and third connection areas thereon; rotating means including an input shaft of predetermined flexibility being connected to one end of said torsion shaft to rotate said input means at a substantially constant velocity; first, second, and third printer drums secured to said first, second, and third connection areas respectively; said drums having printing characters thereon; and magnetically operated exciter means acting on the opposed ends of said torsion shaft to retard them as the torsion shaft is rotated by said rotating means to cause the second drum to oscillate in opposed relationship with said first and third drums at substantially the resonant frequency of said drums and input means to produce a dwell in the rotational movement of each said drum for a cycle of oscillation, with the second drum experiencing any one of said dwells at a time when the first and third drums are rotating at substantially twice the velocity of said input means.

Claim 4

A printer comprising rotatable input means including a torsion shaft having first, second, and third connection areas thereon; rotating means including an input shaft of predetermined flexibility being connected to one end of said torsion shaft to rotate said input means at a substantially constant velocity; first, second, and third printer drums secured to said first, second, and third connection areas respectively; said drums having printing characters thereon; and magnetically operated exciter means acting on the opposed ends of said torsion shaft to retard them as the torsion shaft is rotated by said rotating means to cause the second drum to oscillate in opposed relationship with said first and third drums at substantially the resonant frequency of said drums and input means to produce a dwell in the rotational movement of each said drum for a cycle of oscillation, with the second drum experiencing any one of said dwells at a time when the first and third drums are rotating at substantially twice the velocity of said input means.

Claim 5

A printer comprising: a rotatable input means including a tubular torsion shaft having first, second, and third connection areas thereon; rotating means for rotating said input means at a substantially constant velocity and including an input shaft means which includes an input shaft inserted inside said torsion shaft and is secured to said third connection area, which is located inside said tubular shaft; first and second printer drums secured to said first and second connection areas respectively, said drums having printing characters thereon; and magnetically operated exciter means including a first exciter located near one end of said torsion shaft and a second exciter located near the remaining end thereof; said exciters being adjusted to operate 180* out of phase with each other; each said exciter acting on its associated end of the torsion shaft to retard its rotation as the torsion shaft is rotated by said rotating means to cause said drums to oscillate in opposed relationship to each other to produce a dwell in the rotational movement of each drum for a cycle of oscillation, with the first of said printer drums experiencing any one of said dwells at a time when the second printer drum is rotating at substantially twice the velocity of said input means.

Claim 6

A printer comprising: a rotatable input means including a tubular torsion shaft having first, second, and third connection areas thereon; rotating means for rotating said input means at a substantially constant velocity and including an input shaft means which includes an input shaft inserted inside said torsion shaft and is secured to said third connection area, which is located inside said tubular shaft; first and second printer drums secured to said first and second connection areas respectively, said drums having printing characters thereon; and magnetically operated exciter means including a first exciter located near one end of said torsion shaft and a second exciter located near the remaining end thereof; said exciters being adjusted to operate 180* out of phase with each other; each said exciter acting on its associated end of the torsion shaft to retard its rotation as the torsion shaft is rotated by said rotating means to cause said drums to oscillate in opposed relationship to each other to produce a dwell in the rotational movement of each drum for a cycle of oscillation, with the first of said printer drums experiencing any one of said dwells at a time when the second printer drum is rotating at substantially twice the velocity of said input means.

Claim 7

The printer as claimed in claim 1 in which the characters on said first and second drums are arranged in lines with the lines of characters of said first drum being staggered with respect to the characters on the second drum when the drums are at rest, but the lines of characters of both said drums become aligned with a printing line during the dwells of their respective drums when oscillating at said resonant frequency; said lines of characters being parallel to one another and to the rotating axis of said shaft.

Claim 8

The printer as claimed in claim 1 in which said first and second drums have equal rotating masses, and each of said drums has an inner end and an outer end, with the first drum having its outer end secured to said first area and the second drum having its outer end secured to said second area; the inner ends of said drums being adjacent to and spaced from each other.

Claim 9

The printer as claimed in claim 2 in which said third connection area on said torsion shaft is midway between said first and second connection areas and in which said drums have rotating axes which are coincident with the rotating axis of said shaft.

Claim 10

The printer as claimed in claim 2 further comprising first, second, and third groups of print hammers positioned along a print line and associated with said first, second, and third printer drums, respectively; each of the hammers of said groups of hammers being adapted to be energized when the associated one of said drums is experiencing a dwell.

Claim 11

The printer as claimed in claim 7 in which the characters on said first, second, and third drums are arranged in lines which are parallel to the said rotating axis of said shaft; said lines of characters on said first and second drums being aligned with each other but offset with respect to the lines of characters on said third drum.

Claim 12

The printer as claimed in claim 13 further comprising first and second groups of print hammers positioned along said print line and associated with said first and second printer drums, respectively; each of the print hammers of said groups of hammers being adapted to be energized when the associated one of said drums is experiencing a dwell.

Claim 13

The printer as claimed in claim 3 in which said rotating means further comprises: a driving shaft detachably connected to one end of said input shaft; and support means for detachably and rotatably supporting the remaining end of said input shaft so as to enable said input shaft along with said torsion shaft, and said first drum and second drum secured thereto to be removed as a unit from said printer.

Claim 14

The printer as claimed in claim 2 in which said first and second exciters are adjusted to operate in phase with each other.

Claim 15

The printer as claimed in claim 11 in which the second drum has a rotating mass which is equal to the combined rotating mass of said first and third drums.

Claim 16

The printer as claimed in claim 3 in which the characters on said drums are arranged in lines, with the lines of characters on the first printer drum being staggered with respect to the lines on the second drum when the drums are at rest; but the lines of characters of both of said drums become aligned wIth a printing line during the dwells of their respective drums.

Claim 17

The printer as claimed in claim 3 in which each said exciter has radially aligned stator poles and rotor poles lying in planes which are parallel to and spaced from each other and which planes are perpendicular to the rotating axes of said first and second drums; said poles being trapezoidally shaped in cross section, with the rotor poles being attached to the torsion shaft for rotation therewith and the stator poles being stationary relative thereto.

Claim 18

A printer comprising: rotatable input means including a torsion shaft having a plurality of connection areas thereon; rotating means for rotating said input means at a substantially constant velocity; first and second groups of printer drums, with each said drum being secured to said torsion shaft at one of said connection areas; and magnetically operated exciter means acting on the opposed ends of said torsion shaft to retard them as the torsion shaft is rotated by said rotating means to oscillate said first and second groups of drums at substantially the resonant frequency of said input means and drums to cause each group of drums to periodically dwell a predetermined number of times for each revolution of said input means; the drums of the first group experiencing said dwells at times when the drums of the second group are rotating at substantially twice the velocity of said rotating means; said exciter means including a first exciter located near one of said opposed ends of said torsion shaft and a second exciter located near the remaining said end; and said rotating means including a shaft of predetermined flexibility being connected to one end of said torsion shaft.

Claim 19

A printer comprising: rotatable input means including a torsion shaft having a plurality of connection areas thereon; rotating means for rotating said input means at a substantially constant velocity; first and second groups of printer drums, with each said drum being secured to said torsion shaft at one of said connection areas; and magnetically operated exciter means acting on the opposed ends of said torsion shaft to retard them as the torsion shaft is rotated by said rotating means to oscillate said first and second groups of drums at substantially the resonant frequency of said input means and drums to cause each group of drums to periodically dwell a predetermined number of times for each revolution of said input means; the drums of the first group experiencing said dwells at times when the drums of the second group are rotating at substantially twice the velocity of said rotating means; said exciter means including a first exciter located near one of said opposed ends of said torsion shaft and a second exciter located near the remaining said end; and said rotating means including a shaft of predetermined flexibility being connected to one end of said torsion shaft.

Claim 20

The printer as claimed in claim 15 further comprising first and second groups of print hammers associated with the first and second groups of drums respectively; the first and second groups of print hammers being selectively actuated to effect printing when the drums of their associated groups are experiencing one of said dwells.

Claim 21

The printer as claimed in claim 16 in which said drums have lines of characters thereon, with the lines being parallel to the rotating axis of said drums; and with the lines of characters of the drums of the first group being staggered with respect to the lines of characters of the drums of the second group.

Claim 22

The printer as claimed in claim 1 in which said rotating means further includes an extension shaft on the remaining end of the torsion shaft, which extension shaft is identical to said input shaft; reaction masses secured to the free ends of said input and extension shafts; each said reaction mass having a supporting member to rotatably support the torsion shaft; and means for rotating the reaction mass secured to the input shaft at a constant velocity.

Claim 23

The printer as claimed in claim 18 in which each supporting member is a tubular extension of its associated reaction mass, with each said tubular extension extending towards the associated said first and second connection areas and providing a bearing surface for rotatably supporting the torsion shaft.

Claim 24

The printer as claimed in claim 19 in which the characters on said drums are arranged in lines, with the lines of characters of the first drum being staggered with respect to the lines of characters of the second drum while the drums are at rest, but the lines of characters of both said drums become aligned with a printing line during the dwells of their respective drums.

Claim 25

The printer as claimed in claim 20 in which each said exciter has radially aligned stator poles and rotor poles lying in planes which are parallel to each other and perpendicular to the rotating axis of the torsion shaft.