Abstract A tabulation and margin control structure for use with a character-by-character printer having a margin stop rack and a tab rack each supported for pivotal and longitudinal motion away from a home position. In response to a start tab signal, the tab rack is pivoted to rotate tab stop members into engaging relationship with a tab pawl member and in response to the pivotal motion of the tab rack, an escapement pawl is extracted from the engaged rack tooth to allow carrier motion. In response to the engagement of the tab pawl member with a tab stop, the tab rack is moved longitudinally and produces an electrical signal which initiates a reverse pivotal motion of the tab rack to terminate tab motion and reengage the escapement pawl with the associated rack. In response to the carrier entering a zone defined by the position of the right-hand margin stop member, the margin stop rack is pivoted and an electrical signal provided indicative of entry into the zone. In response to a carrier return signal, the carrier is moved to the left until a projection on the carrier engages the left-hand margin stop member, thereby moving the margin stop rack longitudinally. In response to said last mentioned longitudinal motion, an electrical signal is generated to terminate the carrier return motion.
Inventors
👤 Donald L Rolph
👤 Ronald Tristram
Bibliographic Details
Application Number—
JurisdictionUS
Data Sourcegoogle_patents
Last Synchronized2026-10-27 08:24
CPC Classifications
B; B41; B41J; B41J25/00; B41J25/02; B41J25/18
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
312 words
A tabulation assembly comprising: a tab rack supported for pivotal and longitudinal motion away from a home position; first bias means for urging said tab rack towards said home position; a tab stop member mounted on said tab rack; a support rail having rack teeth and supported in a position parallel to the longitudinal direction of said tab rack; carrier means mounted on said support rail for letter spacing motion relative to and parallel to said tab rack; second bias means for urging said carrier means in a letter space direction; first pawl means mounted on said carrier means for engaging one of said rack teeth of said support rail to inhibit the letter spacing motion of said carrier means; second pawl means mounted on said carrier means; first means for pivoting said tab rack away from said home position; pawl extracting means responsive to the said pivotal motion of said tab rack for extracting said first pawl means from the engaged one of said rack teeth of said support rail; said second bias means moving said carrier means with said letter spacing motion in response to the extraction of said first pawl means; said second pawl means engaging said tab stop member in response to the letter spacing motion of said carrier means; said tab rack being moved longitudinally away from said home position by the force of said second bias means after said second pawl means has engaged said tab stop member; said first means being responsive to the longitudinal motion of said tab rack for pivoting said tab rack back to said home position; and third bias means responsive to the pivoting of said tab rack back to its home position for pivoting said first pawl means into engagement with one of said rack teeth of said support rail for terminating the letter spacing motion of said carrier means.
Claim 2
Dependent Claim
312 words
A tabulation assembly comprising: a tab rack supported for pivotal and longitudinal motion away from a home position; first bias means for urging said tab rack towards said home position; a tab stop member mounted on said tab rack; a support rail having rack teeth and supported in a position parallel to the longitudinal direction of said tab rack; carrier means mounted on said support rail for letter spacing motion relative to and parallel to said tab rack; second bias means for urging said carrier means in a letter space direction; first pawl means mounted on said carrier means for engaging one of said rack teeth of said support rail to inhibit the letter spacing motion of said carrier means; second pawl means mounted on said carrier means; first means for pivoting said tab rack away from said home position; pawl extracting means responsive to the said pivotal motion of said tab rack for extracting said first pawl means from the engaged one of said rack teeth of said support rail; said second bias means moving said carrier means with said letter spacing motion in response to the extraction of said first pawl means; said second pawl means engaging said tab stop member in response to the letter spacing motion of said carrier means; said tab rack being moved longitudinally away from said home position by the force of said second bias means after said second pawl means has engaged said tab stop member; said first means being responsive to the longitudinal motion of said tab rack for pivoting said tab rack back to said home position; and third bias means responsive to the pivoting of said tab rack back to its home position for pivoting said first pawl means into engagement with one of said rack teeth of said support rail for terminating the letter spacing motion of said carrier means.
Claim 3
Dependent Claim
65 words
The combination as set fortH in claim 1 wherein said pawl extracting means comprises a linkage mounted on said carrier means and having a first end for engaging said first pawl means to extract said first pawl means from the engaged rack tooth of said support rail, and having a second end for sensing when said tab rack is pivoted away from said home position.
Claim 4
Dependent Claim
23 words
The combination as set forth in claim 2 wherein said linkage comprises a single assembly pivoted intermediate its ends on said carrier means.
Claim 5
Dependent Claim
38 words
The combination as set forth in claim 2 wherein said tab rack includes a planar surface for engaging said second end of said linkage in response to the pivoting of said tab rack away from its home position.
Claim 6
Dependent Claim
16 words
The combination as set forth in claim 1 wherein said first means comprises a rotary electromagnet.
Claim 7
Dependent Claim
46 words
The combination as set forth in claim 5 and including electrical contact means responsive to the longitudinal motion of said tab rack away from its home position for providing an electrical signal to said rotary electromagnet for pivoting said tab rack back to its home position.