Printer with print wheels having coded perforations for selective positioning

Claim 2

A printer employing a plurality of print wheels on a shaft, each carrying two sets of perforations, first set for coded groups of perforations, each group in a predetermined pattern of perforation positions, each coded group identifying by its position on the wheel a symbol on the print wheel, each group having N perforation positions and the code being in the form of a unique combination of perforations and no perforations in said positions, and a second set of perforations in groups, each group being arranged in said predetermined pattern and having a hole in every position, each group in said second set being available for sensing the coded groups on a turning print wheel while all other print wheels are at rest, each with a symbol in proper aligned position for printing at a printing stations, means for rotating one print wheel at a time while the rest of the print wheels are stationary with a group of sensing perforations in each stationary wheel in line with a group of sensing perforations in all other stationary wheels for permitting light to pass through all sensing perforations of aligned groups of said second set to N photocells, one photocell for each perforation position at one end of said shaft, said light being interrupted only by said coded groups of perforations of said first set of perforations in said turning print wheel as they rotate past said sensing groups in line with said photocells, each of said coded groups being disposed to have its perforation positions to bE in line with perforation positions of said aligned sensing groups in stationary wheels as said turning wheel brings each coded group into a position to block light to said photocells.

Claim 3

A printer as defined in claim 1 including a comparator connected to receive signals from said photocells for comparison with a coded group of N signals specifying a symbol to be positioned at said printing station, and means responsive to said comparator for stopping said turning wheel when signals produced in said photocells in response to the interruption of light by a unique coded group of perforations coincide with said signals to said comparator specifying the symbol to be printed, whereby a symbol identified by the position of said unique coded group of perforations is positioned at said print station.

Claim 4

A printer as defined in claim 2 wherein said means for turning one print wheel at a time is comprised of means for turning said shaft, a slip clutch coupling each print wheel to said shaft, separate means for holding each print wheel in a stationary position, a separate actuating means for each holding means responsive to a control signal for causing said holding means to release a print wheel for rotation, and means for removing said control signal from an actuating means when said comparator detects coincidence.

Claim 5

In a printer having a plurality of axially aligned print wheels, each to be individually set with a selected symbol on the circumferential surface thereof in an indexed position at a print station in line with symbols similarly set on all other print wheels, an improved apparatus for setting said print wheels comprised of: a first set of perforations in said wheel arranged in uniformly spaced groups, each group consisting of a plurality of perforations in a particular pattern such that perforations of all groups coincide with perforations of groups in adjacent print wheels when at rest with symbols in said indexed position, a second set of perforations in said wheels arranged in groups of one to N perforations in a pattern of perforation positions coinciding with N perforations of a group in said first set in an adjacent print wheel when one is rotated relative to the other to bring the two groups opposite each other, said groups of said second set being interspaced with said groups of said first set, and each group of said second set having a unique combination of perforations according to a predetermined code, every unique combination specifying a symbol on said surface by its spatial relationship therewith, said relationship being the same for every code group and symbol combination, means for transmitting light through one group of said first set of each stationary print wheel in alignment, a set of N photocells for detecting light through N perforations of said aligned groups of said stationary wheels, said photocells being arranged in a pattern corresponding to said pattern of perforation positions of said coded groups in said second set, means for providing a group of N coded digital signals for specifying a symbol on a particular print wheel to be positioned at said print station, means for comparing said group of N coded digital signals with output signals from said photocells, and means for turning the print wheel to be positioned with said specified symbol in said print station until said comparing means detects a coincidence between output signals of said photocells and said group of N coded digital signals specifying said symbol.

Claim 6

In a printer having a plurality of axially aligned print wheels, each to be individually set with a selected symbol on the circumferential surface thereof in an indexed position at a print station in line with symbols similarly set on all other print wheels, an improved apparatus for setting said print wheels comprised of: a first set of perforations in said wheel arranged in uniformly spaced groups, each group consisting of a plurality of perforations in a particular pattern such that perforations of all groups coincide with perforations of groups in adjacent print wheels when at rest with symbols in said indexed position, a second set of perforations in said wheels arranged in groups of one to N perforations in a pattern of perforation positions coinciding with N perforations of a group in said first set in an adjacent print wheel when one is rotated relative to the other to bring the two groups opposite each other, said groups of said second set being interspaced with said groups of said first set, and each group of said second set having a unique combination of perforations according to a predetermined code, every unique combination specifying a symbol on said surface by its spatial relationship therewith, said relationship being the same for every code group and symbol combination, means for transmitting light through one group of said first set of each stationary print wheel in alignment, a set of N photocells for detecting light through N perforations of said aligned groups of said stationary wheels, said photocells being arranged in a pattern corresponding to said pattern of perforation positions of said coded groups in said second set, means for providing a group of N coded digital signals for specifying a symbol on a particular print wheel to be positioned at said print station, means for comparing said group of N coded digital signals with output signals from said photocells, and means for turning the print wheel to be positioned with said specified symbol in said print station until said comparing means detects a coincidence between output signals of said photocells and said group of N coded digital signals specifying said symbol.

Claim 7

A printer comprising: a plurality of print wheels, each carrying two sets of perforations arranged in radially aligned groups, each group having one or more perforations, all groups of a first set having a minimum number, N, of perforations in a fixed pattern for use as light paths through all axially aligned print wheels while at rest in an indexed position during the sensing of coded groups of a second set interspaced between groups of said first set in one Of said print wheels while being selectively caused to rotate, each code group of said second set uniquely identifying a symbol, each symbol being positioned with the same spatial relationship to the code group of perforations which uniquely identifies it, a shaft and means for rotating said shaft, each of said print wheels being axially mounted on said shaft and coupled to said shaft by a friction clutch, a plurality of latching means, a separate one for each print wheel for holding said print wheels at rest in said indexed position with a selected one of said symbols on one print wheel in line with all other symbols selected on other wheels for printing at a print station, means for directing light through N light paths provided by a group of perforations of said first set in one print wheel at rest aligned with groups of perforations of said first set in all other print wheels at rest, a number of photocells, one for each of said N light paths positioned to receive light in said paths, means for providing a group of N coded digital signals for specifying a symbol on a particular print wheel to be positioned at said print station, means for individually unlatching said latching means for said particular print wheel, means for comparing said coded signals specifying a symbol to be selected with coded signals produced by said photocells in response to perforations of said coded groups in said particular print wheel interrupting said light paths, and means responsive to said comparator for causing said latching means to again hold said particular wheel stationary, whereby said latching means stops said rotating wheel in a position with said specified symbol on the circumferential surface thereof in said print position at said print station.

Claim 8

A printer comprising: a plurality of print wheels, each carrying two sets of perforations arranged in radially aligned groups, each group having one or more perforations, all groups of a first set having a minimum number, N, of perforations in a fixed pattern for use as light paths through all axially aligned print wheels while at rest in an indexed position during the sensing of coded groups of a second set interspaced between groups of said first set in one Of said print wheels while being selectively caused to rotate, each code group of said second set uniquely identifying a symbol, each symbol being positioned with the same spatial relationship to the code group of perforations which uniquely identifies it, a shaft and means for rotating said shaft, each of said print wheels being axially mounted on said shaft and coupled to said shaft by a friction clutch, a plurality of latching means, a separate one for each print wheel for holding said print wheels at rest in said indexed position with a selected one of said symbols on one print wheel in line with all other symbols selected on other wheels for printing at a print station, means for directing light through N light paths provided by a group of perforations of said first set in one print wheel at rest aligned with groups of perforations of said first set in all other print wheels at rest, a number of photocells, one for each of said N light paths positioned to receive light in said paths, means for providing a group of N coded digital signals for specifying a symbol on a particular print wheel to be positioned at said print station, means for individually unlatching said latching means for said particular print wheel, means for comparing said coded signals specifying a symbol to be selected with coded signals produced by said photocells in response to perforations of said coded groups in said particular print wheel interrupting said light paths, and means responsive to said comparator for causing said latching means to again hold said particular wheel stationary, whereby said latching means stops said rotating wheel in a position with said specified symbol on the circumferential surface thereof in said print position at said print station.

Claim 9

In a printer comprised of a plurality of print wheels on a common shaft, each print wheel being divided into a plurality of sectors and having a plurality of symbols, one symbol on every other sector, an improved mechanism for positioning said wheels individually to print desired symbols through the use of groups of coded perforations in said print wheels, each of said print wheels having coded perforations in predetermined positions, one group of coded perforations for each symbol in a sector of said wheel, each intermediate sector between every pair of adjacent coded sectors having a perforation in the position of every permissible perforation of each of said code groups, means for transmitting a light beam through each permissible perforation of each of said code groups in an intermediate sector of each print wheel while stationary with intermediate sectors aligned, means for rotating one print wheel at a time, means for individually positioning said print wheels as they are rotated, one at a time, by sensing said light transmitted through code perforations in a turning wheel and through aligned perforations in intermediate sectors of all other wheels which are stationary, and bringing said turning wheel to rest with its intermediate sectors aligned with intermediate sectors of all other wheels.

Claim 10

In a printer comprised of a plurality of print wheels on a common shaft, each print wheel being divided into a plurality of sectors and having a plurality of symbols, one symbol on every other sector, an improved mechanism for positioning said wheels individually to print desired symbols through the use of groups of coded perforations in said print wheels, each of said print wheels having coded perforations in predetermined positions, one group of coded perforations for each symbol in a sector of said wheel, each intermediate sector between every pair of adjacent coded sectors having a perforation in the position of every permissible perforation of each of said code groups, means for transmitting a light beam through each permissible perforation of each of said code groups in an intermediate sector of each print wheel while stationary with intermediate sectors aligned, means for rotating one print wheel at a time, means for individually positioning said print wheels as they are rotated, one at a time, by sensing said light transmitted through code perforations in a turning wheel and through aligned perforations in intermediate sectors of all other wheels which are stationary, and bringing said turning wheel to rest with its intermediate sectors aligned with intermediate sectors of all other wheels.

Claim 11

A low cost printer comprising a plurality of print wheels arranged side by side on a common shaft, each with symbols on the circumferential surface thereof and V notches on that surface between symbols, said norches being provided for the purpose of holding said print wheels in an indexed position with a symbol of each in proper alignment with symbols of all other print wheels at a print station, each print wheel being provided with two sets of perforations each set comprising a plurality of grouped perforations, each group having one or more perforations in a fixed pattern of perforations, all groups of one set having at least N perforations for use only as light paths in sensing coded groups of the other set in one rotating print wheel while all other print wheels are held stationary in an indexed position, the perforations in N perforation positions of the groups in the second set being in the same pattern as the N perforation positions of groups in the first set, and perforations in groups of said second set being provided in said positions in accordance with a predetermined code to uniquely identify symbols by relative position on the print wheel, whereby all perforations in said positions of groups of the first set in one wheel are in line with corresponding positions of all groups of the first set of all other wheels while stationary in said indexed position in order that one group of every wheel will be in line to form N light beam paths from a source, or sources, illuminating N photocells at one end of said print wheels arranged side by side, means for rotating one print wheel at a time, thereby sensing coded groups of perforations in the rotating print wheel as the coded groups of perforation positions on the rotating print wheel pass through a position of alignment with said N light beam paths, means for designating a symbol code for said rotating print wheel, and means for stopping said rotating print wheel when the designated symbol code is detected by said photocells.

Claim 12

A low cost printer comprising a plurality of print wheels arranged side by side on a common shaft, each with symbols on the circumferential surface thereof and V notches on that surface between symbols, said norches being provided for the purpose of holding said print wheels in an indexed position with a symbol of each in proper alignment with symbols of all other print wheels at a print station, each print wheel being provided with two sets of perforations each set comprising a plurality of grouped perforations, each group having one or more perforations in a fixed pattern of perforations, all groups of one set having at least N perforations for use only as light paths in sensing coded groups of the other set in one rotating print wheel while all other print wheels are held stationary in an indexed position, the perforations in N perforation positions of the groups in the second set being in the same pattern as the N perforation positions of groups in the first set, and perforations in groups of said second set being provided in said positions in accordance with a predetermined code to uniquely identify symbols by relative position on the print wheel, whereby all perforations in said positions of groups of the first set in one wheel are in line with corresponding positions of all groups of the first set of all other wheels while stationary in said indexed position in order that one group of every wheel will be in line to form N light beam paths from a source, or sources, illuminating N photocells at one end of said print wheels arranged side by side, means for rotating one print wheel at a time, thereby sensing coded groups of perforations in the rotating print wheel as the coded groups of perforation positions on the rotating print wheel pass through a position of alignment with said N light beam paths, means for designating a symbol code for said rotating print wheel, and means for stopping said rotating print wheel when the designated symbol code is detected by said photocells.

Claim 13

Apparatus as defined in claim 7 wherein said common shaft is being rotated continuously by a motor and said print wheels are held stationary by individual latching means, each of said print wheels being coupled to said shaft by a separate friction clutch, thus causing code groups on one rotating wheel to be driven past the aligned perforations of the remaining print wheels held stationary until the designated code of a symbol is detected by said photocells.

Claim 14

Apparatus as defined in claim 8 wherein the position of the latching means relative to the photocells is such as to stop the rotating print wheel with the selected symbol in a print position.

Claim 15

Apparatus as defined in claim 9 wherein V notches are provided between symbols on said wheels and said latching means comprises a pointed arm which fits into a V notch thereby assuring the selected symbol will come to rest in proper alignment at the print station.