US 3745433 A
Description (OCR text may contain errors)
United States Patent 1 Kelby, Jr. et al. I
[ July 10, 1973 ROTARY & LINEAR MAGNETOMOTIVE POSITIONING MECHANISM  Inventors: Edward Kelby, Jr., Schaumberg;
Alan G. Wallskog, Prospect Heights, both of 111.
 Assignee: Teletype Corporation, Skokie, 111.
 Filed: Feb. 2, 1971  Appl. No.: 112,001
Related US. Application Data  Continuation-impart of Ser. No. 754,427, Aug. 21,
 US. Cl. 318/115, 318/687  Int. Cl. H021; 41/00  Field of Search 318/115, 687, 663
 References Cited UNITED STATES PATENTS 3,394,295 7/1968 Cory 318/115 3,243,238 3/1966 Lyman 318/687 X 3,430,120 2/1969 Kotaka et al. 318/687 X 2,437,904 3/1948 Adams et a1 318/115 X 3,495,145 2/1970 Sordello et al 318/663 Primary Examiner-T. E. Lynch Attorney-J. L. Landis and R. P. Miller  ABSTRACT A positioning mechanism for moving a cylinder axially and rotationally is adapted for a printer which has a cylindrical type carrier on which the dies are arranged in intersecting rows and columns.
A first electrically conductive coil is coaxial with and mounted on one end portion of the cylinder. A second electrically conductive coil has an axis perpendicular to the axis of and is mounted on the other end portion of the cylinder. A pair of permanent magnets are positioned about opposite end portions of the cylinder such that each coil is disposed for magnetic coupling in the magnetic flux field of a corresponding magnet.
By selectively energizing the coils, magnetic effects are produced thereabout for coaction with the permanent magnetic flux fields simultaneously to drive the cylinder axially of and angularly about its axis. A feed back system for sensing the instantaneous longitudinal and angular positions of the cylinder is adapted simultaneously to provide electrical effects, whereby from any axial and angular conditions the cylinder can be driven to any other selected axial and angular conditions.
4 Claims, 5 Drawing Figures PAIENIEU JUL 1 0191s FIG. 2
fl y 5 MA" 2 2 A yw W,
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ATTORNEY FIG. 5
6 WOW 3 K YS w p L mum W MM WA DL E A VI B 3 2 M O 4 6 3 3 4 0 W WP EM EM SA SA. 7 Rn! w 3 3 4 m m T mm W.. E AR 0 WW R WP L AN R HE CG m 9 3 ROTARY & LINEAR MAGNETOMOTIVE POSITIONING MECHANISM This application is a continuation in part of application Ser. No. 754,427, now abandoned filed Aug. 21, 1968.
BACKGROUND OF THE INVENTION Known telegraph receivers and other remotely controlled printers print by driving an inked ribbon into a selected type face or die from an array thereof. Conventionally, the dies in the array are arranged in rows and columns on a carrier which may be a type cylinder, the latter being arranged for movement in intersecting paths, that is, rotationally and axially to align a selected die with a percussive implement for impression on a web. It is this class of printer with which the present invention is concerned. Heretofore, carriers of such printers have been controlled by signal operated mechanical means; and, accordingly, printing speed has been limited by the speed at which such mechanical means function.
SUMMARY OF THE INVENTION It is a primary object of the present invention to maximize printing speed of a printer of the indicated class.
It is another object of the invention to provide an improved positioning mechanism.
To effect the foregoing, and other objects of the invention which will become apparent from ensuing description, a positioning mechanism for a cylinder comprises means for generating a first magnetic flux field. An electrically conductive coil is coupleably disposed in said magnetic flux field for driving the cylinder. Means are provided for producing an output effect representative of the position of the cylinder and for energizing the coil in response to the output effect to generate a second magnetic flux field to coact with the first magnetic flux field and drive the cylinder to a predetermined position.
From another aspect, the foregoing objects are effected, in a positioning mechanism for a plurality of dies which are supported on a carrier in printing apparatus in intersecting rows and columns, by means which magnetomotively drive the carrier in a path defining the vector sum of a pair of intersecting force components which are applied to the carrier in intersecting directions parallel to said rows and columns.
BRIEF DESCRIPTION OF THE DRAWINGS A more complete understanding of the invention may be had by referring to the following Detailed Description when taken in conjunction with the accompanying drawings wherein:
FIG. 1 is a perspective view of a positioning mechanism embodying the invention; a cylinder operated by said mechanism being seen from the front in one extreme axial condition and in a centered rotational condition;
FIG. 2 is an elevational view of said cylinder seen from its back, parts being broken away and parts being shown in section;
FIG. 3 is a sectional view according to the line 3--'3 in FIG. 2;
FIG. 4 is a sectional view according to the line 4-4 in FIG. 2; and
FIG. 5 is a scheme of a circuit for operating said mechanism.
DETAILED DESCRIPTION OF THE INVENTION Referring now to the drawings and more particularly to FIG. 1, the positioning mechanism, generally designated 10, comprises magnet means defined by an axial or lineal positioning permanent magnet 11 and a rotational or angular positioning permanent magnet 12. Magnet 11 is shown as having a C-shaped outer section 13, an integral magnetic end plate 14 and a cylindrical magnetic bearing or inner portion 15 which extends integrally from plate 14 and is disposed concentrically within outer section 13. Magnet 12 similarly has a C- shaped outer section 16 with an integral magnetic end plate 17 from which a magnetic bearing 18 projects inwardly, concentrically with outer section 16.
Herein, the magnets are mounted from a preferably non-magnet base or support member 19. They are carried coaxially from opposed ends of a brass or other magnetic insulating rod 20 in spaced apart alignment; the bearings 18 preferably being of the same diameter.
Magnets 11 and 12 are magnetized such that each of the outer sections 13 and 16 is of a polarity opposite from its corresponding of bearing portions 15 and 17. This arrangement provides a pair of magnetic flux fields comprised of radial lines of magnetic flux partially extending about both bearings. A selected state of magnetization is illustrated in the drawings, North and South polar areas being indicated by the conventional N and S symbols.
A type carrier, herein being in the form of a cylinder 21 is disposed about and concentric with rod 20. It has opposed ends which are slidably supported on bearings 15 and 18 for axial or longitudinal and rotational or angular movement with respect to said rod. The type cylinder, which may be of a conventional non-conductive fabric, such as a plastic, supports a plurality of dies or type faces 22 (only a few of which are numerically identified). They are arranged in horizontal rows a-e (FIG. 1) and vertically arcuate columns I-VII on a portion of the outer surface of the type cylinder, which is disposed medially of magnets 11 and 12.
On its opposed end portions, which are disposed within sections 13 and 16, type cylinder 21 also supports coil means comprised of a pair of electrically conductive coils 23 and 24. They are secured to the outer surface of the cylinder by any suitable means such as an adhesive.
Coil 23 is disposed within magnet 11 and is wound about the outer surface of the cylinder in a helix coaxially with said cylinder. This arrangement coupleably places said last named coil in the air gap 25 (FIG. 2) with each of its strands intersecting the flux field of magnet 11 at right angles such that upon generation of an electrical effect in said coil, an induced magnetic field will be generated thereabout for coacting with the magnetic flux field of magnet .11 and shifting cylinder 21 longitudinally of its axis.
Coil 24 is positioned partially within the magnetic flux field of magnet 12 and is wound wholly in an arcuate plane on the outer surface of type cylinder 21 in a somewhat rectangular picture frame configuration as shown, such that the axis about which it is wound is perpendicular to the axis of said cylinder. Coil 24 is arranged such that at least part of a section 26 of said last coil and running parallel to the axis of the type cylinder is always disposed in the flux free space 27 (FIG. 3) of magnet 12 between its spaced apart ends 47 and 48. However, the strands of section 49 (FIG. 3), which is parallel to section 26, are disposed in air gap 50 at right angles to the lines of flux in the field of said last magnet. Thereby, upon generation of an electrical effect in coil 24, an induced magnet field will be generated thereabout for coacting with the magnetic flux field of magabout which said rod is arranged for angular movement.
Such angular movement is effected through the agency of a pair of pinions 42,42 which are secured to net 12 and angularly displacing or rotating the type cyl- 4 inder about its axis of rotation.
The design and proportioning of magnets 11 and 12 permits a relatively movable web of paper 28 (FIG. 4) to be positioned operatively and closely adjacent dies 22 with an inking member 29, such as a typewriter ribbon or the like, disposed between said web and said dies. A percussive implement, herein shown as a hammer 30, is arranged for selectively driving the web and the inking member toward a selected die 22 to effect the printing of the image of the selected die on the web.
Mechanism 10 may be operated to position a selected die 22 at the printing station, that is in alignment with hammer 30, by employing the exemplary circuit (FIG. Particularly, the feed back system shown therein includes detecting or sensing means comprised of a linear potentiometer 31. It is responsively associated with cylinder 21, being coupled thereto for generating a voltage in a known manner according to the instantaneous condition of said cylinder longitudinally of its axis. To that end, the potentiometer is supported adjacent the cylinder from a bracket 32 (FIG. 2), the latter being fixed and projecting upwardly from base 18. v The output of said potentiometer varies according to the condition of a sensing element, here shown as a rod 33, longitudinally of its axis along which it is arranged for movement parallel to the axis of the cylinder. Such longitudinal movement is effected through the agency of a boss 34. It is carried from an end portion of said rod and is engaged in the space between and bears against a pair of parallel vertically, arcuately extending racks 35,35, secured to the back surface of said cylinder. Thereby, as said cylinder shifts longitudinally, rod 33 will shift correspondingly to move a contact, such as a wiper arm (not shown) in the potentiometer, and generates a corresponding output effect.
The output effect of potentiometer 31 is an input to one side of a servo amplifier 36 through a lead 37. Said servo amplifier is adapted for reception of another signal through lead 38 from an input circuit or character generator 39. The last signal corresponds to a selected one of the columns I-Vll in which a desired or selected type face is disposed. The inputs to servo amplifier 36 are added therein algebraically to produce an output effect which is connected directly to coil 23 through one of its leads 40 for inducing a magnetic flux field thereabout for shifting the cylinder magnetomotively in a straight path from any existing condition to a selected other condition and aligning the column having the selected die 22 with hammer 30.
The feed back system also includes detecting or sensing means comprised of a rotary potentiometer 41. It
' is responsively associated with cylinder 21, being cou pled thereto for generating a voltage according to the instantaneous rotational or angular position of said cylinder about its axis. To that end potentiometer 41 is also supportedfrom bracket 32; and said potentiometer has an-output which varies according to the angular condition of said rod 33 about its longitudinal axis rod 33 and operably mesh with rack gears 35,35. Thereby, each angular condition of cylinder 21 has a corresponding angular rod condition. By squaring rod 33 (as shown in FIG. 4) along substantially its entire length, it is adapted rotationally to drive a contact, such as a wiper arm (not shown) in potentiometer 41 to an angular position corresponding to eachangular position of the cylinder, thereby to cause corresponding output effects from potentiometer 41, regardless of the longitudinal condition of said rod.
The output effect of potentiometer 41 is an input to one side of servo amplifier 43 through a lead 44. The last servo amplifier is adapted for reception of another signal through a lead 45 from character generator 39. The last named signal corresponds to a selected of the rows a-e in which the desired or selected die is disposed. The inputs to servo amplifier 43 are added algebraically therein to produce an output which is connected directly to coil 24 through one of its leads 46 for inducing a magnetic flux field for angularly or rotationally displacing said cylinder magnetomotively in an arcuate path about its axis from any existing condition to a selected other condition and aligning the row having the selected die with hammer 30.
By way of example, the linear potentiometer 31 can be of the type manufactured by Helipot Division of Beckman Industries and identified by the company as Model Number 1431-10-0; the rotary potentiometer 41 can be of the type manufactured by New England Instrument Company and identified by that company as Model Number 78EBBl02, and the servo-amplifiers 36 and 43 can be of the type manufactured by Inland Controls Incorporated and identified by that company as Model 300B.
By reason of the foregoing construction any selected die 22 can be aligned with hammer. 30 for printing. Die selection can be through the agency of a known typewriter key (not shown) to which character generator 39 can be directly or indirectly responsive by known means (not shown) to produce a pair of output effects through leads 38 and 45 characteristic of the row and column in which the corresponding die is disposed. Such outputs can be algebraically added simultaneously in servo amplifiers 36 and 43 to provide simultaneous signals which are being fed back to the servo amplifiers from potentiometers 3land 41 and representative of the instantaneous angular and longitudinal conditions of cylinder 21. In consequence, simultaneously a pair of resultant amplifier outputs will be generated to coils 23 and 24, if the cylinder is to move both angularly and lineally, for simultaneously effecting both movements which will translocate the selected die from its position immediately prior to selection to a position aligned with hammer 30 for printing. The movement will be along a vector path having a lineal coordinate axially of said cylinder and an arcuate coordinate concentric with the cylinder axis.
Although only one embodiment of the invention is shown in the drawing and described in the foregoing specification, it will be understood that the invention is not limited to the specific embodiment shown but is capable of modification, rearrangement and substitution of parts and elements without departing from the scope of the invention.
1. A mechanism for shifting to a station any one of an array of elements supported on a cylinder mounted for movement in intersecting first and second dimensions, each element having an address defined by intersecting coordinates related to said dimensions, and comprising:
first means for magnetomotively moving said cylinder to any selected position longitudinally of said first dimension in the absence of a force for moving said cylinder longitudinally of said second dimension;
second means for magnetomotively moving said cylinder to any selected position longitudinally of said second dimension in the absence of a force for moving said cylinder longitudinally of said first dimension;
third means for simultaneously generating a pair of first signals representative of the coordinates of any selected address of said cylinder;
a linear potentiometer for generating one of a pair of second signals;
a rotary potentiometer for generating the other of said pair of second signals; fourth means movable linearly and rotationally in response to corresponding movement of said cylinder for changing said pair of second signals so that said pair of second signals is representative of the coordinates of the actual position of said cylinder;
fifth means for developing a first output from one of the signals of each of said pairs of first and second signals;
sixth means for developing a second output from the other of the signals of each of said pairs of first and second signals; and
seventh means for simultaneously imposing said out puts on said first and second means and moving said cylinder in a third dimension resulting from the forces tending to move said cylinder longitudinally of said first and second dimensions.
2. A mechanism for positioning a cylinder to align any position on the surface thereof with a reference station and comprising:
a first conductive coil mounted coaxially on one end portion of said cylinder;
second conductive coil mounted on the other end portion of said cylinder in an arcuate plane, said second coil wound about an axis perpendicular to the axis of said cylinder; and
a pair of magnetic flux fields disposed about said cylinder ends and cut by said coils for (a) moving said cylinder when said coils are selectively energized either in a circular path to any selected position angularly about the cylinder axis or a linear dimension to any selected position longitudinally of said axis and (b) moving said cylinder in a vector course when said coils are simultaneously energized, said vector course including movement longitudinally and angularly about said axis.
3. A combination according to claim 2 further having:
means for generating a pair of first signals corresponding to the angular and linear coordinates of an address of any selected position on said cylinder;
means for simultaneously and independently generating a pair of second signals corresponding to the angular and linear coordinates of the address of an actual position on said cylinder; and
means for generating a pair of combined outputs from (a) the signals corresponding to the linear coordinates and (b) the signals corresponding to the angular coordinates, and for imposing each output on one of said coils to move said cylinder from an actual position to an address longitudinally of and angularly about said axis and having any desired angular and lineal coordinates.
4. A combination according to claim 1 wherein said fourth means comprises:
a rod secured to said cylinder and mounted for reciprocation in a path parallel to the axis of said cylinder; and
means having parts on said rod and said cylinder for rotating said rod in response to rotation of said cylinder.