The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Feb. 07, 1978
Filed:
Nov. 03, 1975
Robert H Schaffer, Mystic, CT (US);
Harris-Intertype Corporation, Cleveland, OH (US);
Abstract
An improved drive system for driving one unit of a printing press includes first and second meshing gears which are fixedly connected with blanket cylinders of the printing unit. Third and fourth gears are driven by the associated blanket cylinder gears and are connected with the plate cylinders of the printing unit through harmonic drive units. To tend to minimize backlash and enable the blanket cylinders to be thrown off while maintaining the gears in meshing engagement, the plate and blanket cylinder gears have design pitch circles which intersect. The harmonic drive units have internal gears which, during operation of the printing press, are effective to rotate the plate cylinders relative to the plate cylinder gears. To enable the plate and blanket cylinders to be driven at the same surface speed, it is necessary to offset or compensate for the effect of the gears in the harmonic drive units. In one embodiment of the invention, the effect of the gears in the harmonic drive units is compensated for by providing the blanket cylinder gears with fewer teeth than are necessary to drive the plate cylinders at the same surface speed as the blanket cylinders. However, the blanket cylinder gears have a larger design pitch diameter than standard gears of the same pitch to enable their design pitch circles to intersect the design pitch circles of the plate cylinder gears. In another embodiment of the invention, the number of teeth on the blanket cylinder gears is sufficient to rotate the plate cylinders at the same surface speed as the blanket cylinders and the gears have standard pitch diameters. In this embodiment of the invention, motors in the harmonic drive units are operated to drive the harmonic drive units in a manner to offset or compensate for the effect of the gears in the harmonic drive units.