File:The Bell System technical journal (1922) (14733607786).jpg

Identifier: bellsystemtechni17amerrich (find matches)
Title: The Bell System technical journal
Year: 1922 (1920s)
Authors: American Telephone and Telegraph Company
Subjects: Telecommunication Electric engineering Communication Electronics Science Technology
Publisher: (Short Hills, N.J., etc., American Telephone and Telegraph Co.)
Contributing Library: Prelinger Library
Digitizing Sponsor: Internet Archive

View Book Page: Book Viewer
About This Book: Catalog Entry
View All Images: All Images From Book
Click here to view book online to see this illustration in context in a browseable online version of this book.

Text Appearing Before Image:
rbon copy can be made if desired. To obtain low first cost thismachine has a moving paper carriage and to secure a satisfactoryprinted record it employs ribbon inking and a typewheel arrangementwhich is a sort of cross between conventional typebar and typewheeldesigns. This typewheel is an assembly employing a small individualtype pallet for each separate character. In the process of printing acharacter, a striking arm somewhat like the shank of a typebar comesforward and forces the individual type pallet against the ribbon tomake an impression on the paper. The typewheel is rotated todifferent positions to select the different characters to be typed. Inthis way satisfactory inking and a clear cut impression without sideprint is obtained, which compares favorably with the record obtained FUNDAMENTALS OF TELETYPEWRITERS 633 on a typebar machine or typewriter. The entire machine costsappreciably less than the more comprehensive No. 15 machine. TheNo. 26 machine is illustrated in Fig. 7.
Text Appearing After Image:
Fig. 7—No. 26 teletypewriter. Features of Tape Teletypewriters In the case of tape teletypewriters it is also necessary to have a cleanprinted record and occasionally there is a need for carbon copies.Accordingly, the tape machine standard for the Bell System is a type-bar machine using an inking ribbon and known as the No. 14 teletype-writer. It is illustrated in Fig. 8. 634 BELL SYSTEM TECHNICAL JOURNAL A feature worthy of note is that with this machine typing alwaysoccurs at the same point introducing a problem in connection withplaten wear. If the platen were fed by the usual ratchet in, say, 36steps per revolution, there would be heavy wear concentrated at these36 points and the platen would require frequent replacement to pre-

Note About Images