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US4167342A Expired / Lapsed US ⏱️ 0.0 years remaining

Control system for matrix print head

Assignee: Ricoh Printing Systems America Inc
•
Filing: 1977-06-13
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Granted: 1979-09-11
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Expires: 1997-06-13
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Abstract

Abstract A system for printing dot-matrix characters wherein a double column of dot forming elements is used, and no single dot forming element is required to print more often than once in any four column interval of printed text. Means for timing the actuation of the dot forming elements wherein the "on" time of the individual actuators can be longer than the time interval between columns is included.

Inventors

  • 👤 Dan C. Mower
  • 👤 Peter H. Wolf
  • 👤 Boyd E. Slade
  • 👤 David Albertalli

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-26 16:21
CPC Classifications
B; B41; B41J; B41J2/00; B41J2/485; B41J2/505; B41J2/5056; B41J2/51

Claims Analysis

Total Claims: 19
Claim 1
Independent Claim 159 words
In a system for printing dot-matrix characters of the type having a printing head and means for causing said printing head to scan across a printing medium at a predetermined speed which comprises: (a) a printing head including a plurality of groups of dot forming elements, each of said elements being individually actuatable to print in any matrix column, one of said groups having at least one dot forming element horizontally aligned with a dot forming element of another of said groups; and (b) character generator means for generating actuation signals for said dot forming elements, said character generator means including memory means for storing the matrix locations of dots required to form characters, said locations not including locations which would cause any dot forming element to be actuated more than once for each four matrix columns and whereby for certain columns of certain characters dots are formed by elements of a plurality of groups of dot forming elements.
Claim 2
Dependent Claim 159 words
In a system for printing dot-matrix characters of the type having a printing head and means for causing said printing head to scan across a printing medium at a predetermined speed which comprises: (a) a printing head including a plurality of groups of dot forming elements, each of said elements being individually actuatable to print in any matrix column, one of said groups having at least one dot forming element horizontally aligned with a dot forming element of another of said groups; and (b) character generator means for generating actuation signals for said dot forming elements, said character generator means including memory means for storing the matrix locations of dots required to form characters, said locations not including locations which would cause any dot forming element to be actuated more than once for each four matrix columns and whereby for certain columns of certain characters dots are formed by elements of a plurality of groups of dot forming elements.
Claim 3
Dependent Claim 12 words
The system as recited in claim 1 where said plurality is two.
Claim 4
Dependent Claim 32 words
A system for printing dot-matrix characters as recited in claim 1 wherein the spacing between said columns of dot forming elements of said printing head is an integral number of matrix columns.
Claim 5
Dependent Claim 22 words
A method of printing characters as recited in claim 3 wherein said columns of dot forming elements are spaced about 0.030 inches.
Claim 6
Dependent Claim 46 words
A system for printing dot-marix characters as recited in claim 3 and further including a clock providing a series of substantially uniformly spaced signals for causing said actuation signals corresponding to said dot locations to be sequentially outputted, column by column, from said character generator means.
Claim 7
Dependent Claim 49 words
A system for printing dot-matrix characters as recited in claim 4 and further including means whereby said dot locations outputted to one of said groups of dot forming elements are delayed a predetermined number of clock signals with respect to the other of said groups of dot forming elements.
Claim 8
Dependent Claim 20 words
A system for printing dot-matrix characters as recited in claim 6 and further including means for changing said predetermined number.
Claim 9
Independent Claim 90 words
A method of printing dot-matrix characters using dot forming elements which comprises: (a) dividing the dots of each character into a plurality of groups whereby any dot to be printed in any row of any character is separated from any other dot in said row belonging to the same group by more columns than the number of said groups; and (b) printing each of said groups of dots by a separate group of dot forming elements said printing for certain columns of certain characters including dots belong to different groups.
Claim 10
Independent Claim 90 words
A method of printing dot-matrix characters using dot forming elements which comprises: (a) dividing the dots of each character into a plurality of groups whereby any dot to be printed in any row of any character is separated from any other dot in said row belonging to the same group by more columns than the number of said groups; and (b) printing each of said groups of dots by a separate group of dot forming elements said printing for certain columns of certain characters including dots belong to different groups.
Claim 11
Dependent Claim 24 words
The method of printing characters as recited in claim 8 where each of said groups of dot forming elements is arranged in columnar fashion.
Claim 12
Dependent Claim 31 words
The method of printing characters as recited in claim 9 wherein said dots of each characters are divided into two groups and said dot forming elements are arranged in two columns.
Claim 13
Dependent Claim 32 words
The method of printing characters as recited in claim 10 wherein said columns of dot forming elements are spaced apart a distance equal to an integral number of columns of said matrix.
Claim 14
Dependent Claim 17 words
The method of printing of characters as recited in claim 11 where said integral number is three.
Claim 15
Dependent Claim 23 words
The method of printing characters as recited in claim 10 wherein said columns of dot forming elements are spaced apart about 0.030 inches.
Claim 16
Dependent Claim 16 words
The method of printing characters as recited in claim 13 where said integral number is three.
Claim 17
Independent Claim 133 words
A method of equalizing wear of dot forming elements in a row of a dot matrix print head having a plurality of dot forming elements in said row which comprises the steps: (a) determining the relative frequency of usage of each character in the font of characters to be printed; (b) assigning each dot in said row of each character in said font a weight proportional to said relative frequency of usage of said character; (c) dividing said dots into a number of groups equal to the number of dot forming elements in said row, the sum of the weights of all dots in each of said groups being substantially equal; and (d) assigning the task of printing each of said groups of dots to a different one of said dot forming elements.
Claim 18
Independent Claim 133 words
A method of equalizing wear of dot forming elements in a row of a dot matrix print head having a plurality of dot forming elements in said row which comprises the steps: (a) determining the relative frequency of usage of each character in the font of characters to be printed; (b) assigning each dot in said row of each character in said font a weight proportional to said relative frequency of usage of said character; (c) dividing said dots into a number of groups equal to the number of dot forming elements in said row, the sum of the weights of all dots in each of said groups being substantially equal; and (d) assigning the task of printing each of said groups of dots to a different one of said dot forming elements.
Claim 19
Dependent Claim 62 words
The method as recited in claim 15 and further including the step of determining the characters in said font having a number of dots in said row of which said number of dot forming elements in said row is a divisor, and dividing the dots in said row of each of said characters equally among said groups without assigning any weights thereto.

References Cited (Backward Citations)

US3938641A Cited
US3925790A Cited
DE2515557A1 Cited
US4010835A Cited
US4033444A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1982-09-10 1983-03-12 1983-09-11 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1986-09-10 1987-03-12 1987-09-11 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1990-09-10 1991-03-12 1991-09-11 $7700.00 Window Closed / Lapsed

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