US 4,309,945 AGranted

Flexographic printing unit

AssigneeMaryland Cup Corporation

InventorThomas E. Marion

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Abstract

An improved flexographic type printing unit is provided in which only an ink transfer cylinder, plate cylinder and impression cylinder are needed with the transfer cylinder immersed in an ink fountain and cooperating with an adjustable doctor blade. Bearing traction roll drives and spacing means are utilized and the impression and transfer cylinders are mounted on swinging arms positioned by hydraulic or pneumatic cylinders to obviate the need for machined slides and surfaces and multiple adjustments at opposite ends of these cylinders. An eccentric structure in a freewheeling impression cylinder provides an accurate web thickness adjustment for the unit. A second embodiment of the flexographic printing unit includes a planetary gear drive for changing the registration of the print-to-blank or print-to-print of the plate cylinder as it engages a web.

Claims32

Dependent claims

In a printing means for printing repetitive patterns on a travelling web printing medium, including a driven printing plate cylinder and inking and impression cylinders driven thereby, all of said cylinders being substantially mutually parallel and positioned between upstanding spaced side plates on a machine frame, the improvement comprising:

an integral axial shaft on said inking cylinder;
a first pair of swinging arms pivotally mounted between said side plates and journalling opposite ends of said integral inking cylinder shaft for rotation therein;
first fluid actuating means selectively positioning said first swinging arms and said inking cylinder with respect to said plate cylinder;
an axial mounting shaft in said impression cylinder;
a second pair of swinging arms pivotally mounted between said side plates and journalling said mounting shaft for limited rotation therein;
second fluid actuating means selectively positioning said second swinging arms and said impression cylinder with respect to said plate cylinder;
fine adjustment means for said impression cylinder comprising a cylindrical bushing eccentric with said axial mounting shaft within each end of said impression cylinder, bearing means mounting said impression cylinder for free rotation on said bushings and adjusting means on at least one of said arms for imparting a selected rotational adjustment to said mounting shaft and said bushings to cause selective translation of said impression cylinder toward and away from said place cylinder;
an integral axial drive shaft on said plate cylinder;
and
bearing traction means on opposite ends of each of said shafts interengaged to drive said inking cylinder therethrough and to index said inking and impression cylinders with respect to said plate cylinder;
said impression cylinder being freewheeling to be driven by said plate cylinder through web of printing medium nipped therebetween.

8 more elements

Printing means for printing successive patterns on a travelling web of printing medium comprising:

a machine base with upstanding side plates;
plate cylinder means journalled for rotation between said side plates in a fixed axial position and including a plate cylinder surface and a shaft rotatable therewith having first bearing traction rollers keyed thereto for rotation in synchronism with said plate cylinder surface;
drive means rotating said plate cylinder shaft;
an ink fountain mounted between said side plates adjacent said plate cylinder;
and
ink transfer cylinder means mounted between said side plates intermediate said plate cylinder means and said ink fountain means for transferring ink from the latter to the former;
said ink transfer cylinder means being substantially parallel to said plate cylinder and including:
a coaxial integral shaft rotatable therewith,
first and second swinging arm means pivoted to respective ones of said side plates and being driven about said pivots by first and second fluid actuating means,
journal means mounting opposite ends of said coaxial integral shaft in respective ones of said swing arm means, and
second bearing traction rollers keyed on opposite ends of said coaxial integral shaft in driving engagement with said first bearing traction rollers on said plate cylinder shaft;
and
an impression cylinder means mounted for free rotation between said side plates and having a cylindrical impression surface substantially parallel with and cooperating with said plate cylinder means to nip a web of printing medium therebetween;
said impression cylinder means including:
an interior mounting shaft substantially parallel to the central axis of said cylindrical impression surface,
thrid and fourth swinging arm means including journal means mounting opposite ends of said mounting shaft for rotation therein pivoted to said respective ones of said side plate means and being driven about pivots by third and fourth fluid actuating means,
third bearing traction rollers freely rotatable on opposite ends of said mounting shaft and engaged with said first bearing traction rollers to initially index said cylindrical impression surface with said plate cylinder surface,
eccentric bearing means on said mounting shaft adjustably mounting said cylindrical impression surface for free rotation eccentrically of said mounting shaft, and
mounting shaft engaging means precluding free rotation thereof and providing selective rotational positioning thereof and of said eccentric bearing means to provide a fine nip adjustment between said impression surface and said plate cylinder surface.

16 more elements

an integral axial shaft on said inking cylinder;
a first pair of swinging arms pivotally mounted between said side plates and journalling opposite ends of said integral inking cylinder shaft for rotation therein;
first fluid actuating means selectively positioning said first swinging arms and said inking cylinder with respect to said printing plate cylinder;
an axial mounting shaft in said impression cylinder;
a second pair of swinging arms pivotally mounted between said side plates and journalling said mounting shaft for limited rotation therein;
second fluid actuating means selectively positioning said second swinging arms and said impression cylinder with respect to said printing plate cylinder;
fine adjustment means for said impression cylinder comprising a cylindrical bushing eccentric with said axial mounting shaft within each end of said impression cylinder, bearing means mounting said impression cylinder for free rotation on said bushings and adjusting means on at least one of said arms for imparting a selected rotational adjustment to said mounting shaft and said bushings to cause selective translation of said impression cylinder toward and away from said printing plate cylinder;
an integral axial drive shaft on said printing plate cylinder;
a registration adjusting means for adjusting the registration of said printing plate cylinder relative to said travelling web;
and
bearing traction means on opposite ends of each of said shafts interengaged to drive said inking cylinder therethrough and to index said inking and impression cylinders with respect to said printing plate cylinder;
said impression cylinder being freewheeling to be driven by said printing plate cylinder through web of printing medium nipped therebetween.

9 more elements

Printing means for printing successive patterns on a travelling web of printing medium comprising:

a machine base with upstanding side plates;
plate cylinder means journalled for rotation between said side plates in a fixed axial position and including a plate cylinder surface and a shaft rotatable therewith having first bearing traction rollers keyed thereto for rotation in synchronism with said plate cylinder surface;
drive means rotating said plate cylinder shaft;
a registration adjusting means for adjusting the registration of said plate cylinder surface relative to said travelling web;
an ink fountain mounted between said side plates adjacent said plate cylinder;
and
ink transfer cylinder means mounted between said side plates intermediate said plate cylinder means and said ink fountain means for transferring ink from the latter to the former;
said ink transfer cylinder means being substantially parallel to said plate cylinder and including:
a coaxial integral shaft rotatable therewith,
first and second swinging arm means pivoted to respective ones of said side plates and being driven about said pivots by first and second fluid actuating means,
journal means mounting opposite ends of said coaxial integral shaft in respective ones of said swing arm means, and
second bearing traction rollers keyed on opposite ends of said coaxial integral shaft in driving engagement with said first bearing traction rollers on said plate cylinder shaft;
and
an impression cylinder means mounted for free rotation between said side plates and having a cylindrical impression surface substantially parallel with and cooperating with said plate cylinder means to nip a web of printing medium therebetween;
said impression cylinder means including:
an interior mounting shaft substantially parallel to the central axis of said cylindrical impression surface,
third and fourth swinging arm means including journal means mounting opposite ends of said mounting shaft for rotation therein pivoted to said respective ones of said side plate means and being driven about pivots by third and fourth fluid actuating means,
third bearing traction rollers freely rotatable on opposite ends of said mounting shaft and engaged with said first bearing traction rollers to initially index said cylindrical impression surface with said plate cylinder surface,
eccentric bearing means on said mounting shaft adjustably mounting said cylindrical impression surface for free rotation eccentrically of said mounting shaft, and
mounting shaft engaging means precluding free rotation thereof and providing selective rotational positioning thereof and of said eccentric bearing means to provide a fine nip adjustment between said impression surface and said plate cylinder surface.

17 more elements

A printing apparatus for printing repetitive patterns on a travelling web printing medium, including a driven printing plate cylinder and inking and impression cylinders driven thereby, all of said cylinders being substantially mutually parallel and positioned between upstanding spaced side plates on a machine frame, the improvement comprising:

an integral axial shaft on said inking cylinder;
a first pair of swinging arms pivotally mounted between said plates and journalling opposite ends of said integral inking cylinder shaft for rotation therein;
first fluid actuating means selectively positioning said first swinging arms and said inking cylinder with respect to said printing plate cylinder;
an axial mounting shaft in said impression cylinder;
a second pair of swinging arms pivotally mounted between said side plates and journalling said mounting shaft for limited rotation therein;
second fluid actuating means selectively positioning said second swinging arms and said impression cylinder with respect to said printing plate cylinder;
an integral axial drive shaft on said printing plate cylinder;
a registration adjusting means for adjusting the registration of said printing plate cylinder relative to said travelling web;
and
traction means on opposite ends of each of said shafts for driving said inking cylinder therethrough and to index said inking and impression cylinders with respect to said printing plate cylinder;
said impression cylinder being freewheeling to be driven by said printing plate cylinder with said travelling web of printing medium nipped therebetween.

8 more elements

Dependencies are inferred from the claim text.