US3696204A

US3696204A - Type carrier assembly

Info

Publication number: US3696204A
Application number: US41335A
Authority: US
Inventors: Alan G Wallskog
Original assignee: Teletype Corp
Current assignee: AT&T Teletype Corp
Priority date: 1970-05-28
Filing date: 1970-05-28
Publication date: 1972-10-03
Anticipated expiration: 1989-10-03
Also published as: CA936808A

Abstract

Drivable type dies of a teleprinter are supported in intersecting rows and columns from a type carrier which is arranged for adjustment in intersecting paths at successive stations to which the carrier is moved for presenting any selected die in a position for character reproduction. Adjustment and movement of the carrier and translocation of an impeller to successive printing stations for driving successively selected dies between print and non-print modes results from magnetomotive phenomena generated by a linear electric motor.

Description

SID-15 SR FIPSSSQ, KR

QJHHEEQQ S18E08 P369111 Wallslrog 1541 TYPE CARRIER ASSEMBLY [72] Inventor: Alan G. Wallskog, Prospect Heights,

[73] Assignee: Teletype Corporation, Skokie, Ill.

[22] Filed: May 28, 1970 [21] Appl. No.2 41,335

[ 51 Oct. 3, 1972 3,369,163 2/1968 Peterson ..235/151 l 1 1 1,769,780 7/1930 Hallwood ..177/212 OTHER PUBLICATIONS Smeltzer, Linear Actuator, IBM Tech. Disclosure Bulletin, Vol. 4, No. 3, August 1961.

Poyloujadoff, Linear Induction Machines, Spectrum, 2/71, p. 72 80.

Primary Examiner-Kathleen H. Claffy Assistant Examiner-William A. Helvestine [5 7] ABSTRACT Drivable type dies of a teleprinter are supported in intersecting rows and columns from a type carrier which is arranged for adjustment in intersecting paths at successive stations to which the carrier is moved for presenting any selected die in a position for character reproduction. Adjustment and movement of the carrier and translocation of an impeller to successive printing stations for driving successively selected dies between print and non-print modes results from magnetomotive phenomena generated by a linear electric motor.

14 Claims, 9 Drawing Figures PATENTEDnm 3 I972 3 696, 204

sum 1 or 4 FIG. I

30 III! 44 II as 4 H-Q INVENTOR ALAN G. WALLSKOG ATTORNEY PATENTEDUCT 3 m2 SHEEI 2 OF 4 .2; w V 2?- m 2 2. 4 n

PATENTEDIIIIG I972 3 696, 204

SHEET

3 or 4 ISO FIG. 6

FIG. 7

VERTICAL I90 POSITION ADDER ADDER SUBTRACTOR I92 L 5222 66 I80 I74 SPACE HORIZONTAL I82 REGISTER POSIT'ON LIFEED BACK '0) '72 CHARACTER PR'ME L 26 GENERATOR DELAY -IMPELLER I TRIGGER PATENTEDnm 3 I972 3.696.204

saw u or 4 1 w 244\ /248 :QlMPELLER DELAY DELAY 250 242 24o 252-- SPACE POSITION CHARACTER REGISTER REGISTER GENERATOR 258 V ADDER 264 LOCATION 1 1 7 REGISTER PULSE DRIVE I CIRCUIT 272 270 LOCATION r REGISTERR SUBTRACTOR A 1 A 4 l FIG. 9

DRIVE CIRCUIT 214 T TYPE CARRIER ASSEMBLY FIELD OF THE INVENTION BACKGROUND OF THE INVENTION A teleprinter adapted as a terminal is often associated with an intelligence storage or bank for intelligence translation. Conventionally, a teleprinter has a carrier for dies of a plurality of symbols or characters from which selection is made for printing. The dies are arranged selectively to be driven at a printing station by an impeller into a printing mode.

In one class of teleprinters, the web on which intelligence is reproduced is immobilized from horizontal shifting during printing. To effect printing then, the impeller is adapted for translocation in steps to successive adjoining horizontally aligned stations. At each successive station a selected die is presented; and to that end means are adapted for moving the die carrier to successive stations and for adjusting the carrier to align a selected die with the impeller. I

In the art of intelligence recovery, significant resources have been and currently are being invested to increase the speed of intelligence reproduction to maximize the availability of intelligence bank or storage facilities or the intelligence contained therein. Production costs of improvement which heretofore have been developed parallel increase in speed the speed of intelligence recovery achieved thereby and accordingly, tend to limit exploitation of the innovations.

The disclosure of the present invention is related to material disclosed and claimed in two contemporaneously filed applications Ser. No. 41,485 in the name of G. Cless and Ser. No. 41,486 in the name of G. Cless and J. L. DeBoo.

It is an object of the present invention rapidly to translate intelligence.

It is another object of the invention to minimize the cost of intelligence translation.

It is a further object of the invention to provide an improved terminal for a data storage system.

Moreover, it is an object of the invention to provide an improved teleprinter.

SUMMARY OF THE INVENTION To effect the foregoing and other objects which shall become apparent from ensuing description, the present invention has been adapted for a teleprinter. A plurality of dies which comprise the printing means of the teleprinter are supported in a plurality of rows and columns from a carrier which is moveably arranged for disposition at a printing station. A linear electric motor with a combination output having axial components in a plurality of dimensions is adapted for adjusting the carrier to present any selected die at the printing station.

From another aspect, the foregoing objects are achieved according to the invention summarized as aforesaid with means for moving any selected die between passive and printing modes and additional means associated with the motor for translocating said moving means to successive printing stations.

From still another aspect, the foregoing objects are achieved according to the present invention by algebraically combining a spacing position signal with a signal representative of the horizontal or column position within the type carrier of the desired type die and using this combined signal to energize a type-carrier moving means to bring the desired type die to the printing station.

BRIEF DESCRIPTION OF THE DRAWINGS In the ensuing detailed description, reference is had to the accompanying drawings on which:

FIG. 1 is a perspective view of the invention embodied in a teleprinter and looking toward the front thereof from its platen;

FIG. 2 is a perspective view of the teleprinter looking from the front thereof toward the platen, parts being broken away for illustration;

FIG. 3 is a view according to the section line 33 on FIG. 1;

FIG. 4 is a view according to the section line 4-4 on FIG. 1;

FIG. 5 is an electrical scheme for the teleprinter;

FIG. 6 is a partial view the teleprinter showing an alternate embodiment of the type carrier positioning mechanism;

FIG. 7 is a schematic diagram of a logic system for operating the embodiment illustrated in FIG. 6;

FIG. 8 is a schematic diagram of another alternate embodiment of the horizontal or column position adjusting mechanism with an impeller position adjusting mechanism; and

FIG. 9 is a schematic diagram of a logic system for operating the embodiment illustrated in FIG. 8.

DETAILED DESCRIPTION-FIRST EMBODIMENT Referring now to the accompanying drawings and more particularly to FIGS. 1 through 5, inclusive, a teleprinter 10 is referred to. This teleprinter 10 is more fully described and is claimed in the above-mentioned G. Cless application, which is incorporated herein by reference. However, sufficient of the disclosure of the G. Cless application is reproduced herein for purpose of convenient illustration of the present invention. The teleprinter 10 comprises a platen 12 which may be of conventional construction and cylindrical configuration and is immobilized from lateral or horizontal shifting. The platen is adapted for supporting a web 14 (FIG. 3), such as paper or the like on which intelligence is reproduced and is rotatable about its longitudinal and horizontally extending axis for shifting the web vertically a line at a time in a conventional manner. Means (not shown) which may be conventional are arranged for supporting an inked ribbon l6 longitudinally of the axis of platen l2 and spaced slightly forwardly of the web 14.

A box or carrier 18 is disposed slightly forwardly from ribbon 16; and is arranged for movement horizontally, longitudinally of the axis of platen 12. The carrier supports a font of type or dies 20 (FIG. 1) which are arranged in horizontal rows 19 and in vertical columns 21 only some of which are numbered. In accordance with conventional practice, the dies may be faced with alphanumeric characters and selected other designs or symbols; and each has an exposed shank 22 which extends forwardly from the carrier.

By means not shown, each of the dies 20 is biased or urged forwardly toa non-print or passive mode in which its printing face is spaced slightly forwardly from rib bon 16. However, each die is mounted for movement horizontally transversally of the axis of platen 12 between its passive or non-print mode and a print mode in which it has been driven rearwardly against its normal bias into contact with ribbon 16 for printing in a conventional fashion on web 14.

Means for moving dies 20 between passive and printing modes comprises an impeller or solenoid 24 whose driven member terminates in a striker 26. The latter is normally biased or urged to a withdrawn or forward position and is arranged for movement in a path coincident with the path of movement of a selected die. Moreover, the dimensions of the striker are such that when the impeller is actuated, only a selected die will be driven toward a print mode.

Carrier 18 is arranged for adjustment vertically as well has horizontally; and the parts are proportioned such that at any adjusted position a single one of the dies 20 will be disposed suitably for printing at a printing station. Teleprinter is adapted for a printing station which moves horizontally a space at a time, whereby a succession of symbols can be formed to print a line of intelligence. Accordingly, impeller 24, the position of which defines a printing station, is arranged for successive horizontal movements.

In accordance with the present invention, a linear electric motor, generally designated 28, comprises means for adjusting carrier 18 along a vector having values referable to a pair of orthogonal coordinates (herein being vertical and horizontal) in a planar or two-axis system to select a die for printing. Moreover, said motor comprises means for moving said carrier to successive printing stations; and said motor also comprises means for translocating impeller 24 to successive printing stations simultaneously with movement and adjustment of carrier 18.

Motor 28 is comprised of a permanent magnet 30 and a magnet loop defining a magnetic circuit. The latter is fashioned from a pair of horizontally extending parallel magnetic bars or

rails

32 and 34 which are preferably of equal length. They have opposed

end portions

36 and 38 which are connected by a magnetic bridge 40 and

opposed end portions

42 and 44 which are connected by a magnetic bridge 46.

Rails

32 and 34 and

bridges

40 and 46 are fabricated from a material of low magnetic reluctance and retentivity, such as soft iron, said rails being magnetic segments in said magnetic circuit between which a non-magnetic or air gap 48 is formed.

As illustrated, the permanent magnet may be a rectangular block which is disposed within the magnetic loop. It is magnetized through its thickness (its North and South poles being conventially designated N and S) with one of its polar faces secured by a suitable cement to the inner face of rail 32 and its opposite polar face parallel to the inner face of rail 34. Thereby, a magnetic flux field is generated across gap 48.

In accordance with the teachings of the above-mentioned contemporaneously filed application of G. Cless and J. L. DeBoo, a pair of

electrical coils

50 and 52, respectively, have

coil segments

54 and 56 which are disposed in air gap 48 whereby upon development of an electrical effect in said coils, they become inductively coupled in the magnetic flux field. Coil 50 is circumposed about rail 34 with the direction of its winding in segment 54 cutting the lines of flux in air gap 48 such that when a current passes through said coil a magnetomotive force is generated impelling coil 50 longitudinally of said rail in a horizontal path defined thereby and parallel to rows 19 of said dies. The coil 52 is used to move the type carrier 18 vertically.

Coil 50 is physically connected to a coupler fashioned as a trolley 58 which has a body 60 from which are supported a plurality of upper and lower guide rollers 62. They engage a pair of opposed ribs 63 fashioned on and longitudinally of the upper and lower surfaces of rail 34 for moving the trolley longitudinally, thereof. Coil 50 is rigidly secured to body 60 and, when said coil is motivated, trolley 58 will be caused to move horizontally and in a direction, to or fro, corresponding to the direction of current flowing in said coil.

Means associated with motor 28 for translocating impeller 24 to successive printing stations comprises an electrical coil or winding 68. It is circumposed about rail 34 and has a vertical segment with strands extending transversely of said rail 34 and disposed in air gap 48 such that upon production of an electrical effect in said coil, a magnetomotive force will be generated causing coil movement in a horizontal path longitudinally of rail 34.

A bracket 72 which supports impeller 24 is rigidly secured to coil 68 for translocating said impeller horizontally parallel to rows 19, the direction of translocation being according to the direction of current flow in said coil. Translocation of the impeller is facilitated by a pair of opposed rollers 74 which are carried from bracket 72 and engage ribs 63 for guiding the impeller longitudinally of rail 34.

Exemplary means for simultaneously adjusting carrier 18 whereby any selected die is disposed at a printing station and for stepping or moving said carrier to successive printing stations and also for correspondingly translocating impeller 24 comprises circuitry 76 (FIG. 5). This circuitry is described more fully in the abovementioned Gv Cless application.

In consequence of the foregoing, through the agency of a linear electric motor with plural outputs, simultaneously carrier 18 can be adjusted vertically and horizontally for bringing a die. corresponding to an available character into a printing position while the carrier is also moved horizontally to a proper position of succession corresponding to a printing station, and while impeller 24 is stepped or advanced from an existing to the next ensuing printing station. Moreover, in the present embodiment adjustment and movement of carrier 18 will be along a vector comprised of a pair of values corresponding to intersecting coordinates in a planar, two-axis system and correlatable to effects generated in

coils

50 and 52.

SECOND EMBODIMENT-SCISSORS POSITIONING MECHANISM Referring now to FIGS. 6 and 7 of the accompanying drawing, there is shown in FIG. 6 an alternative embodiment of the present invention wherein the

coils

54 and 56 and their associated mechanical arrangements cooperating to position type carrier 18 have been replaced by a pair of

coils

140 and 142 which are mounted on two

trolleys

144 and 146. The two trolleys are mounted on the magnetic rail 34 in much the same way that the trolley 58 is mounted on the rail 34 in FIG. 2. The

coils

140 and 142 are independently operable. A scissors mechanism 150 is pivotally attached to the

trolleys

144 and 146 at two

pivots

152 and 154, respectively, which are at the ends of two bars 156 and 1580f the scissors mechanism 150. One of the bars 156 is pivoted at approximately its midpoint to the other bar 158. The other end of the bar 156 is pivotally mounted to the type carrier 18 at a pivot 162, and the other bar 158 is slidably mounted in a slot 164 in the type carrier 18.

It can be seen that, if the

trolleys

144 and 146 are made to move horizontally across the magnetic rail 34 but always remain the same distance apart, the type carrier 18 will be adjusted horizontally but not vertically. It can also be seen from the scissors mechanism 150 that, if the

trolleys

144 and 146 are moved closer together, the scissors mechanism 150 will cause the type carrier to rise in the vertical direction as shown in FIG. 6. Similarly, if the

trolleys

144 and 146 are made to move away from each other, the scissors mechanism H50 will cause the type carrier 18 to move down in a vertical direction as shown in FIG. 6.

Referring now to FIG. 7, in order to adjust the positions of the

trolleys

144 and 146 along the rail 34 in FIG. 6, signals representative of the location of the desired type die within the type carrier 18 are generated at an output terminal 170 by a character generator circuit 172. The horizontal component of this type element location signal is delivered to a horizontal positioning register 174. The vertical position signal designating the vertical position within the type carrier 18 of the desired type die is delivered to a vertical position register 176.

At a desired timing instant, a trigger signal is generated at an output terminal 178 of the character generator 172. This trigger signal is delivered to the horizontal position register 174, the vertical position register 176, and to a space register 180. The space register contains information representative of the position along the platen 12 at which printing is to occur, that is, the location of the printing station. The output of the spacing register 180 is delivered to a feedback amplifier 182 which drives the coil 68 that is connected to the impeller bracket 72 in order to position the impeller 24 (FIG. 2) at the printing station. The feedback circuit 104 provides the feedback signal for the feedback amplifier 182, as explained in connection with FIG. 5.

The spacing signal from the space register 180 is also supplied to an adding circuit 184 which adds the space signal with the horizontal type die location signal from the horizontal position register 174 to arrive at an algebraic sum of the printing station signal and the signal representative of the horizontal location or column of the die within the type carrier 18. The output of the adder circuit 184 is delivered to another adder 186 and to a subtractor circuit 188. The output of the vertical position register is also delivered to the adder 186 and the subtracter 188. Therefore, the output of the vertical position register is added to the horizontal position signal from the adder 184 in the adder 186 and the output of the vertical position register is subtracted from the output of the adder circuit 184 in the subtracter circuit 188.

The outputs of the adder 186 and the subtracter 188 are delivered to a pair of

feedback amplifiers

190 and 192 which are connected to the coils 142 and of the mechanism of FIG. 6. Suitable feedback circuits 194 and 196 are also connected to the feedback amplifier and 192. It can readily be seen from FIG. 7 that the position of the

coils

140 and 142 and with them their associated

trolleys

144 and 146 represent the sum of the horizontal spacing and horizontal type carrier position. The difference between these two coils (and their associated trolleys) represents the vertical position of the desired type die within the type carrier 18.

The trigger signal from the output terminal. 178 is also delivered to a delay circuit 198. When vertical and horizontal movements of the type carrier 18 have been accomplished, the delay circuit 198 will have completed its delay interval and will send a signal to the impeller 24 to cause its striker 26to move the selected type die to its printing mode.

THIRD EMBODIMENT-STEPPING MOTOR AND CABLE DRIVE Referring now to FIGS. 8 and 9 of the accompanying drawing, there is shown in FIG. 8 anotheralternate embodiment of the present invention in which a stepping motor 200 rotates a drive pulley 202. A cable 204 is wrapped around the drive pulley 202 and around four fixed but rotatable pulleys 205. The cable 204 is fastened at each end to a cradle 206 in which the type carrier 208 is slidably mounted. The type carrier is very similar to the type carrier 18 in the previous embodiments; however, it is free to be adjusted in the vertical direction by mechanism not shown in FIG. 8. The type carrier 208 is rigidly restrained to follow the cradle 206 as the cradle 206 moves in the horizontal direction. Therefore, it can be seen that as the stepping motor 200 steps in the clockwise direction as shown in FIG. 8, the cradle 206 and the type carrier 208 are moved to the right. Conversely, as the stepping motor 200 steps in the counterclockwise direction, the cradle 206 and the type carrier208 are moved to the left as shown in FIG. 8. The drive pulley 202 is proportioned such that each step of the stepping motor 200 moves the type carrier 208 in the horizontal direction by a distance equal to the distance between adjacent columns of type dies in the type carrier 208. The columns of type dies on the type carrier are separated from each other by a distance equal to the spacing of characters on the printed page.

Another drive pulley 210 is firmly mounted to the drive pulley 202 and rotates in' rigid synchronism therewith. A second cable 214 is wound around the drive pulley 210, and the cable 214 is firmly attached at its end points to an impeller mechanism 216 that carries an impeller 24 which has been explained previously. The cable 214 is guided around four guide pulleys 217-220, inclusive. Only the bottom two

guide pulleys

217 and 218 rotate about a pair of fixed shafts, 222 and 224'. The upper two

guide pulleys

219 and 220 7 are mounted at the top ends of two radius bars 226 and 228. The lower ends of the two radius bars 226 and 228 are rotatably mounted on the two fixed

shafts

222 and 224. A crossbar 230 is pivotally attached to the radius bars 226 and 228 to form a parallelogram mechanism.

A rack 232 on the crossbar 230 is engaged by a drive gear 236 that is driven by a stepping motor 238. As the stepping motor 238 rotates the drive gear 236, the

pulleys

219 and 220 are moved in substantially a horizontal direction. Horizontal movement of the

pulleys

219 and 220 moves the impeller mechanism 216 horizontally even though the pulley 210 may remain stationary. The leverage of the parallelogram mechanism and the size of the drive gear 236 is such that each step of the stepping motor 238 moves the impeller mechanism 216 by an amount equal to the spacing between adjacent columns of type dies on the type carrier 208.

In the operation of the mechanism shown in FIG. 8, successive steps of the stepping motor 200 move the type carrier 208 and the impeller 24 through successive columns or spaces to the right. However, the impeller 24 is not expected always to strike the same type die or the same column of type dies. The stepping motor 200 steps the pulley 202 clockwise or counterclockwise so as to move the type carrier 208 to the right or to the left in order to place the desired column at the printing station. However, the impeller 24 is always moved in synchronism with the type carrier 208 by reason of the

pulleys

202 and 210 being locked together and rotated as one. Consequently, the impeller 24 must be provided with facility to move to some degree independently of the type carrier 208, and this is accomplished by the stepping motor 238 and the parallelogram mechanism.

As printing progresses from left to right across a page of paper, the location of the type carrier 208 is always a summation of the location of the printing station across the page and the location within the type carrier of the desired column of type dies. The position of the impeller 24 must correspond only to the location of the printing station; however, the cable 214 for the impeller 24 always moves in synchronism with the cable 204. Consequently, the cable 214 also contains the unwanted summation of the typing station location plus the location within the type carrier of the desired column of type dies. The stepping motor 238 and the parallelogram mechanism is used to subtract the information representing the location of the desired column within the type carrier from the information contained in the position of the cable 214 in order to place the im' peller 24 at the desired printing station.

The operation of the mechanism of FIG. 8 will be more readily understood by referring to the schematic diagram shown in FIG. 9 which shows a character generator 240 which is similar to the character generator 172 of FIG. 7. However, since the embodiment shown in FIG. 8 only relates to the horizontal positioning of the type carrier 208, the vertical type carrier positioning or row adjusting information generated by the character generator 240 is ignored in the schematic diagram of FIG. 9.

An output terminal 242 of the character generator 240 carries the information representing the desired location within the type carrier 208 of the desired column of type dies. At an appropriate time, a trigger signal is generated by the character generator 240 and is emitted at a trigger terminal 244. This trigger signal is sent to a pair of

delay timers

246 and 248 and to a position register 250 and a space register 252. The trigger signal causes the position register 250 to assume a state representing the location signal of the desired column of type dies that is provided by the character generator 240 at the output terminal 242. The space register 252 is merely a counter; and the trigger signal causes it to advance by one count for each character printed in order to cause the printer to space to the right. The space register 252 represents at its output at any instant, the location of the printing station across the width of the page of paper.

The outputs of the position register 250 and the space register 252 are both delivered to an adder circuit 254 which algebraically adds the output of the space register and the output of the position register in order to generate a combined signal representing the actual position that the type carrier must assume in order to place the desired column of type dies in the type carrier 208 into the desired printing station location.

The signal issuing from the adder circuit 254 is sent to a subtractor circuit 256 which has another input derived from a location register 258. The location register 258 contains the algebraic sum of the spacing and column location signals representative of the character just printed. The output from the location register 258 is subtracted from the output of the adder 254 in the subtracter circuit 256. The signal remaining in the subtracter circuit as a result of this subtraction is a representation of the number of steps and the direction of rotation of the stepping motor 200 necessary to move the type carrier 208 to the proper position in order to place the desired column of type dies at the desired printing station. A positive remainder indicates that the stepping motor 200 is to be stepped in the clockwise or in the forward direction in order to move the type carrier 208 to the right. A negative remainder indicates that the stepping motor 200 is to be stepped in the counterclockwise or reverse direction in order to move the type carrier 208 to the left.

The subtracter circuit 256 has a forward output terminal 260 and a reverse output terminal 262. A signal present on the forward output terminal 260 indicates that the stepping motor 200 is to turn in the clockwise direction. However, a signal at the reverse output terminal 262 indicates that the stepping motor 200 is to step in the reverse direction. When the circuitry shown in FIG. 9 has assumed the condition in which the subtracter circuit 256 contains the result of the algebraic sum mentioned above, the delay circuit 248 will complete its delay interval and will issue a signal to a pulse generator circuit 264. In response to that signal, the pulse generator circuit 264 begins delivering timing pulses to the subtracter circuit 256 in order to cause the subtracter circuit to clear itself a step at a time and simultaneously to issue advance pulses at an advance output terminal 266. The signals on the forward output terminal 260, the reverse output terminal 262, and the advance output terminal 266 are all delivered to a motor driver circuit 268 which may be of a type well known in the prior art. The signals from the forward and

reverse output terminals

260 and 262 indicate to the driver circuit 268 which way the motor should turn.

The signals generated at the advance output terminal 266 at intervals determined by the pulse generator 264 indicate how many steps the motor 200 is to step in order to place the type carrier 208 in the desired position. The motor driver circuit 268 causes the stepping motor 200 to step in the desired direction, the proper number of times, as dictated by the subtracter circuit 256.

The signals delivered to the driver circuit 268 are also delivered to the location register 258. These signals are used to advance the location register 258 by an amount equal 'to the number of steps and in the same direction which the stepping motor 200 advances. Therefore, the location register 258 contains at its output for later use in the subtractor 256, the location of the type carrier 208 for that last character printed.

The output of the position register 250 is also delivered to another subtracter 270. Another location register 272 delivers a signal to the subtracter 270. Therefore, the output of the location register 272 is subtracted from the output of the position register 250 in the subtracter 270. The location register 272 contains a representation of the previous position of the stepping motor 238 and the parallelogram mechanism formed by the bars 222 and 228 and the crossbar 230.

The output of the subtracter 270 is delivered to a stepping motor drive circuit 274, using the pulse generator 264 in a manner similar to the way that the stepping motor drive circuit 268 receives its motorstepping commands. The motor drive circuit 274 advances the stepping motor 238 in the desired direction to subtract the column position information from the column position plus the spacing information contained in the position of the cable 214 (FIG. 8). The output of the subtracter is also delivered to the location register 272 in the same manner as the output of the subtracter 256 was delivered to the location register 258.

It is evident from the foregoing that the signals delivered to the stepping

motors

200 and 238 send the type carrier 208 and the impeller mechanism 216 from one printing station to the next. There is no absolute position reference feedback signal in FIG. 9 such as the

feedback amplifiers

194, 196 and 104 of FIG. 7. When the type carrier 208 and the impeller mechanism are returned to the left-hand margin at each carriagereturn operation, some reference can be made. Such a reference and its implementation are within the capability of one skilled in the art. Since such a reference in the system of FIGS. 8 and 9 forms no part of the present invention as related to the embodiment of FIGS. 8 and 9 and is not claimed with reference to that embodiment, it has been omitted from FIGS. 8 and 9 in the interests of simplicity.

Although various specific embodiments of the invention are shown in the drawings and described in the foregoing specification it will be understood that invencarrier which is adjustably arranged for presenting any selected die at a printing station in response to a pair of signals derived from signal generating means and corresponding to a row and a column in which a die corresponding to a character to be reproduced is disposed, an improvement characterized by a linear electric motor with a single magnetic flux field and a pair of electrical coils, each coil mounted in said flux field for movement simultaneously with, and in a direction different from the direction of movement of the other coil in response to tone of said signals; and

means for coupling the forces of the simultaneous movements of said coils and adjusting said carrier to present a selected die for printing.

2. A combination according to claim 1 wherein the motor comprises a pair of spaced apart magnetic segments defining a magnetic circuit with an air gap between said segments and further characterized in that said coils have portions disposed in said gap.

3. A combination according to claim 1 wherein said signal generating means is adapted for producing simultaneous efiects in said coils for driving said carrier in a path having changing values relatable to intersecting coordinates in a two axis system.

4. An apparatus for positioning a type carrier in two dimensions comprising:

a linear motor with two mutually independent outputs having output motions in the same linear dimension; and

means connecting the linear motor outputs to the type carrier for moving the type carrier in said linear dimension by an amount which is a function of the average movement of the two outputs of the motor and for moving the type carrier in a dimension orthogonal to said linear dimension by an amount which is a function of the difference between the movements of the two outputs of the motor.

5. An apparatus according to claim 4 wherein the linear motor with two mutually-independent outputs comprises:

means for generating a magnetic flux field;

two conductive coils comprising said outputs and being mounted in the flux field; and

means for separately passing electric current through the two coils in accordance with the desired position of the type carrier.

6. An apparatus according to claim 5 wherein the field generating means comprises a permanent magnet.

7. An apparatus according to claim 5 wherein the moving means is connected to the two coils.

8. An apparatus according to claim 4 wherein the moving means comprises a scissors mechanism having two bars pivotally interconnected with one end of one of the two bars pivotally connected to one of the two linear motor outputs and one end of the other of the two bars pivotally connected to the other of the two linear motor outputs; and with the other ends of the two bars of the scissors mechanism connected to the type carrier.

9. An apparatus according to claim 8 wherein the other ends of the two bars of the scissors mechanism are connected to the type carrier by the other end of the one bar being pivotally connected to the type carrier and the other end of the other bar being slidably carried on the type carrier.

10. An improved printing method of the type wherein a plurality of dies are arranged in intersecting rows and columns on a carrier which is adjustably arranged for presenting any selected die at a printing sta tion in response to two signals, wherein the improvement comprises:

applying the signals, separately, to a pair of electrical coils magnetomotively disposed in a flux field to move the coils along a linear axis through selected distances governed individually by the two signals; and

moving the carrier along perpendicular axes in response to the movement of the coils to align a selected die at the printing station.

11. A method according to claim wherein the moving step comprises:

moving the type carrier in an axis parallel with the linear axis for a distance generally proportional to the average distance through which the two coils move; and

moving the type carrier in an axis perpendicular to the linear axis for a distance generally proportional to the difference between the distances through which the two coils move.

12. A method according to claim 1 1 wherein:

moving the type carrier in the axis parallel with the linear axis provides column adjustment of the type carrier; and

moving the type carrier in the axis perpendicular to the linear axis provides row adjustment of the type carrier.

13. A method according to claim 1 1 wherein the two moving steps are accomplished simultaneously.

14. In a teleprinter wherein printing means comprises a plurality of dies supported in intersecting rows and columns from a carrier which is adjustably arranged for presenting any selected die at a printing station in response to a pair of signals derived from signal generating means and corresponding to a row and a column in which such die is disposed, an improvement characterized by:

a linear electric motor with first and second electrical coils connected to said signal generating means, said coils arranged for movement simultaneously in first and second directions in response to said signals; and

means for coupling said coils and generating motion in a plurality of dimensions to adjust said carrier and present a selected die for printing.

Claims

1. In a teleprinter wherein printing means comprise a plurality of dies supported in a plane in parallel rows and orthogonally intersecting parallel columns from a carrier which is adjustably arranged for presenting any selected die at a printing station in response to a pair of signals derived from signal generating means and corresponding to a row and a column in which a die corresponding to a character to be reproduced is disposed, an improvement characterized by a linear electric motor with a single magnetic flux field and a pair of electrical coils, each coil mounted in said flux field for movement simultaneously with, and in a direction different from the direction of movement of the other coil in response to tone of said signals; and means for coupling the forces of the simultaneous movements of said coils and adjusting said carrier to present A selected die for printing.

3. A combination according to claim 1 wherein said signal generating means is adapted for producing simultaneous effects in said coils for driving said carrier in a path having changing values relatable to intersecting coordinates in a two axis system.

4. An apparatus for positioning a type carrier in two dimensions comprising: a linear motor with two mutually independent outputs having output motions in the same linear dimension; and means connecting the linear motor outputs to the type carrier for moving the type carrier in said linear dimension by an amount which is a function of the average movement of the two outputs of the motor and for moving the type carrier in a dimension orthogonal to said linear dimension by an amount which is a function of the difference between the movements of the two outputs of the motor.

5. An apparatus according to claim 4 wherein the linear motor with two mutually-independent outputs comprises: means for generating a magnetic flux field; two conductive coils comprising said outputs and being mounted in the flux field; and means for separately passing electric current through the two coils in accordance with the desired position of the type carrier.

10. An improved printing method of the type wherein a plurality of dies are arranged in intersecting rows and columns on a carrier which is adjustably arranged for presenting any selected die at a printing station in response to two signals, wherein the improvement comprises: applying the signals, separately, to a pair of electrical coils magnetomotively disposed in a flux field to move the coils along a linear axis through selected distances governed individually by the two signals; and moving the carrier along perpendicular axes in response to the movement of the coils to align a selected die at the printing station.

11. A method according to claim 10 wherein the moving step comprises: moving the type carrier in an axis parallel with the linear axis for a distance generally proportional to the average distance through which the two coils move; and moving the type carrier in an axis perpendicular to the linear axis for a distance generally proportional to the difference between the distances through which the two coils move.

12. A method according to claim 11 wherein: moving the type carrier in the axis parallel with the linear axis provides column adjustment of the type carrier; and moving the type carrier in the axis perpendicular to the linear axis provides row adjustment of the type carrier.

13. A method according to claim 11 wherein the two moving steps are accomplished simultaneously.

14. In a teleprinter wherein printing means comprises a plurality of dies supported in intersecting rows and columns from a carrier wHich is adjustably arranged for presenting any selected die at a printing station in response to a pair of signals derived from signal generating means and corresponding to a row and a column in which such die is disposed, an improvement characterized by: a linear electric motor with first and second electrical coils connected to said signal generating means, said coils arranged for movement simultaneously in first and second directions in response to said signals; and means for coupling said coils and generating motion in a plurality of dimensions to adjust said carrier and present a selected die for printing.