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

Serial Echo Checking Circuit for Print Hammers

IP.com Disclosure Number: IPCOM000083690D
Original Publication Date: 1975-Jul-01
Included in the Prior Art Database: 2005-Mar-01
Document File: 2 page(s) / 34K

Publishing Venue

IBM

Related People

Hendee, RC: AUTHOR [+2]

Abstract

A signal, indicating hammer fire status, can be provided to a device remote from a printer, by using a single input line for hammer addressing and a single output line for hammer status.

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 100% of the total text.

Page 1 of 2

Serial Echo Checking Circuit for Print Hammers

A signal, indicating hammer fire status, can be provided to a device remote from a printer, by using a single input line for hammer addressing and a single output line for hammer status.

A burst of 132 pulses is sent over an input line, gated with a signal that is active only when no transition of hammer drivers is occurring at AND gate 1. This output steps counter 2 to provide a decoded output at decoder 3. The decoded outputs are then combined with each hammer drive line at a corresponding one of the series of AND gates 5, which are in turn connected to common OR gate 6.

The output from gate 6 results in a serial indication of fired hammers, which can then be used by a control unit for an odd-even check; a count compare, or a determination of the status, by position, of any or all hammers.

The addition of OR gates 4 provide a means of monitoring the hammer status when no hammers should be on.

1

Page 2 of 2

2

[This page contains 2 pictures or other non-text objects]