US 4,393,386 A · Ink jet printing apparatus

Abstract

An ink jet printing apparatus is described wherein an array of ink jet heads of the impulse jet type is compled to print sheets such as envelopes traveling past the heads. The ink jet heads are spaced along the travel path of the sheets and laterally staggered to print different image lines. The apparatus includes a microprocessor and controllers which are associated with individual heads. The controllers include buffers which are loaded with image signals derived from a font memory in correspondence with data to be printed. Presettable delay networks are used in the controllers to precisely determine when an ink jet head is to be printed in relationship with the detection of sheets at a particular distance relative to the heads. The ink jets heads are operated in timed relationship with each other and in synchronism with the traveling sheets while their associated buffers are reloaded at the proper times for a continual printing of different information such as addresses on envelopes.

Claims10

Dependent claims

A computer controlled ink jet apparatus for printing a sequence of sheets with relative movement in a first direction between an ink jet apparatus and the sheets comprising:

an array of ink jet heads disposed to each eject ink drops onto the relatively moving sheets, said ink jet heads each having a plurality of ink ejecting orifices and being positioned along said first direction and displaced laterally relative to one another and to said first direction to print different lines of images on the sheets;
means for generating image signals representative of the ink drops to be ejected by the ink jet heads for the formation of lines of images on the sheets during relative motion between the sheets and the ink jet heads;
storage means for storing image signals for respective ones of said ink jet heads in the array;
means for generating sheet signals, each representative of the arrival of a sheet at a location having a known distance from the ink jet heads in the array;
and
means responsive to the sheet signals for applying said stored image signals to respective ink jet heads for their actuation in a predetermined timed relationship selected to print lines of images on each sheet from the array of ink jet heads at desired sheet locations.

3 more elements

Dependencies are inferred from the claim text.

Ink jet printing apparatus

Life of this patent

Ink jet printing apparatus

Life of this patent

Abstract

Claims10