Dismiss
InnovationQ will be updated on Sunday, Oct. 22, from 10am ET - noon. You may experience brief service interruptions during that time.
Browse Prior Art Database

Reverse Tabulation for Typewriters

IP.com Disclosure Number: IPCOM000090586D
Original Publication Date: 1969-May-01
Included in the Prior Art Database: 2005-Mar-05
Document File: 2 page(s) / 64K

Publishing Venue

IBM

Related People

Walton, ND: AUTHOR

Abstract

Stops 10 of a typewriter tabulation mechanism, as described in U. S. patent 2,854,124, are employed to also control return motion of carriage 1 to permit selective reverse-tab carriage return directly to preset tab on column locations. Depression of a reverse-tab keylever, not shown, causes lever 12 to move upward to lift reverse-tab pawl 13 into the path of a preset tab stop 10. Also, depression of the reverse-tab keylever activates the carriage return mechanism not shown, to initiate carriage motion in the return direction and pivot bellcrank 14 clockwise by a connection through link 15. Bellcrank 14 unlatches reverse-tab slider 16 via link 17 and latching bellcrank 18, which is displaced from pivoted latch pawl 19, to permit slider 16 to move rightwardly.

This text was extracted from a PDF file.
At least one non-text object (such as an image or picture) has been suppressed.
This is the abbreviated version, containing approximately 58% of the total text.

Page 1 of 2

Reverse Tabulation for Typewriters

Stops 10 of a typewriter tabulation mechanism, as described in U. S. patent 2,854,124, are employed to also control return motion of carriage 1 to permit selective reverse-tab carriage return directly to preset tab on column locations. Depression of a reverse-tab keylever, not shown, causes lever 12 to move upward to lift reverse-tab pawl 13 into the path of a preset tab stop 10. Also, depression of the reverse-tab keylever activates the carriage return mechanism not shown, to initiate carriage motion in the return direction and pivot bellcrank 14 clockwise by a connection through link 15. Bellcrank 14 unlatches reverse-tab slider 16 via link 17 and latching bellcrank 18, which is displaced from pivoted latch pawl 19, to permit slider 16 to move rightwardly. Bellcrank 18 also unlatches decelerator bellcrank 19 to allow counterclockwise rotation of it by spring 20 to cock the decelerator mechanism by permitting decelerator drive cam 21 to rotate clockwise under the ordinary escapement pawl mechanism 30 from rack 31 via link 23 and other mechanism described in U. S. Patent 2,872,013.

Unlatching of slider 16 permits it to be driven rightwardly by spring 24 acting on margin control bellcrank 25 and through connecting link 26. Bellcrank 25, in turn, moves the margin control slider 27 rightwardly completing the cocking of the carriage return decelerator system. Rightward movement of the margin control slider 27 engages keyboard lock c...