Automatic compensation for carriage flyback
US4460268A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | May 27, 1983 |
| Grant date | Jul 17, 1984 |
| Priority date | — |
| Expiry date | May 27, 2003 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03B27/527
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A control to automatically adjust the air bleed screw on a pneumatic dashpot to alter the return speed of a scanning carriage. At the start of the carriage flyback, an end of scan position signal is generated and a second signal is generated when the carriage has reached the home position. These two signals conveyed to control logic determine the time period of the scan flyback. The time period of scan flyback is compared to an acceptable window or range of flyback time periods. If the scan flyback time period is outside the range of acceptable time periods, an adjust drive signal is conveyed to an adjust solenoid. The activation of the solenoid causes the solenoid armature to move a ratchet wheel into engagement with the pneumatic dashpot air bleed screw. Upon the succeeding forward or reverse scan of the carriage, a pawl secured to the carriage drive cable engages the ratchet wheel to turn the ratchet wheel in either a clockwise or counterclockwise direction, in turn rotating the air bleed screw either in the counterclockwise or clockwise direction. This will result in an automatic adjustment, either a greater damping or less damping of the pneumatic dashpot, depending upon wheth…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.