Browse Prior Art Database

Control of Relative Upper and Lower Case Printing Force

IP.com Disclosure Number: IPCOM000094871D
Original Publication Date: 1965-Jun-01
Included in the Prior Art Database: 2005-Mar-06
Document File: 2 page(s) / 56K

Publishing Venue

IBM

Related People

Tao, DC: AUTHOR

Abstract

Relative upper and lower case printing impact force is varied by modifying the design configuration of the four bar type actuating linkage.

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 87% of the total text.

Page 1 of 2

Control of Relative Upper and Lower Case Printing Force

Relative upper and lower case printing impact force is varied by modifying the design configuration of the four bar type actuating linkage.

In existing electric type bar typewriters, a resilient power roll selectively drives a four bar linkage as shown in the drawing. The change of linkage configuration caused by case shift, i. e., full to broken line, causes the linkage to demand greater energy from the power roll in upper case than in lower case. While this result is ordinarily desirable for most characters, due to the large surface of upper case characters with respect to lower case characters, there are certain characters, e. g.,*, that require less force for upper case printing than for their associated lower case printing.

By moving the location of connection 10 it is possible to vary the configuration change of the four bar linkage, as between upper and lower case. Thus, the relative energy demanded by the linkage in upper and lower case is modified. To reduce the upper case energy, and hence printing force, relative to the lower case printing force, connection 10 is moved so as to move point R closer to the pivot 12. Point R is the intersection of link 11 with a line drawn between pivot 12 and power roll axis 13. Conversely, to increase the relative energy change, connection 10 is moved so as to move point R further from the pivot 12.

All locations of the connection 10 are preferably located on an ar...