Browse Prior Art Database

Highlighting Feature for Typewriters

IP.com Disclosure Number: IPCOM000052576D
Original Publication Date: 1981-Jun-01
Included in the Prior Art Database: 2005-Feb-11
Document File: 3 page(s) / 74K

Publishing Venue

IBM

Related People

Schaefer, JO: AUTHOR

Abstract

With today's high quality correctable typewriters, the ability to make words stand out is generally limited to underscoring or, in the case of changeable font machines, the interchanging of different type styles. Additionally, some fabric machines offer bi-colored ribbons where accent can be accomplished by using an alternate color.

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 53% of the total text.

Page 1 of 3

Highlighting Feature for Typewriters

With today's high quality correctable typewriters, the ability to make words stand out is generally limited to underscoring or, in the case of changeable font machines, the interchanging of different type styles. Additionally, some fabric machines offer bi-colored ribbons where accent can be accomplished by using an alternate color.

The bi-colored ribbon approach is generally considered a very effective way to accent words. However, the high quality machines using film ribbon systems with correction capability generally can not use this approach without incurring cost and complexity trade-offs that are hard to cost-justify.

A good alternative to the two-color technique is to double-print accented characters, using a slight horizontal displacement between the two.

The mechanism for providing this feature is fairly simple and also provides automatic double-erase. The embodiment shown is only one of many forms such a device can take and was chosen for its relative simplicity for modeling.

The control device for operating the typewriter to effect the highlighting feature is illustrated in Fig. 1. Pawl member 10 may be depressed by a keylever or other keyboard control member in the direction of the arrow in Fig. 1, thus rotating pawl 10 about locating pin 12. As pawl 10 is depressed, pawl surface 14 is moved into engagement with the ratchet teeth of ratchet 16. Ratchet 16 is combined with the six sided cam member 18 which rotates with ratchet 16. The pawl member 10 may be moved rightward as a result of cyclical cam 20 and cam follower/link 22. Cam 20 is attached to one of the cyclical rotating shafts of the typewriter such that it rotates once for each print cycle.

Upon the actuation of pawl member 10 to present pawl surface 14 to ratchet 16, and the initiation of a printing cycle, cam 20 will rotate pulling follower/link 22 and pawl member 10 rightward, thus rotating ratchet 16 by an amount equal to one tooth and will cause the six-sided cam member 18 to rotate, thus forcing follower arm 24 to rise. As follower arm 24 rises, restore spring 26 is tensioned and cables 28, 30, 32 and 34 are pulled. Cable 28 is attached to backspace pawl 36 (Fig. 2) to cause a backward rotation of backspace ratchet 38 by a predetermined amount, typically that which is sufficient to displace the print point by approximately .018 of an inch. Cable 30 is extended to a connection with the cycle clutch bail such that the cycle clutch for the typewriter is prevented from resetting and thus is held withdrawn from the cycle clutch, causing a second machine cycle.

Cable 32 is connected to a device, such as found in Fig. 3, for preventing selection interposers from restoring and thereby insuring that the selection...