Transport system and method for printing plates

A plate handling system for transporting printing plates between workstations in a process workflow, the system comprising:

• a plurality of vacuum gripper end effectors configured to grip the printing plates and mounted to a computer controlled transporter, the transporter configured to translate in at least three orthogonal directions and to rotate about at least one rotational axis;
• at least one sensor for detecting orientation of the plate relative to at least one staging location in the process workflow;
• and
• a controller, connected to the transporter and the at least one sensor, configured to cause the transporter to move based upon programmed instructions in accordance with information provided by the sensor;
• wherein the end effectors are configured to grip the printing plate on an upper surface of the plate, the process workflow comprises an imaging station configured to apply an image to the upper surface of the plate, and a photopolymer curing station comprising a support transparent or translucent to an actinic radiation emitted by the photopolymer curing station, wherein the photopolymer curing station is configured to irradiate both the upper surface and an opposite lower surface of the plate.

A method of processing a printing plate in a plurality of workstations in a process workflow, the method comprising the steps of:

• (a) providing a plate handling system for transporting the printing plate from one workstation to another in the process workflow, the plate handling system comprising a computer controlled transporter configured to translate in at least three orthogonal directions and to rotate about at least one rotational axis, end effectors for gripping the printing plates connected to the transporter, at least one sensor for detecting orientation of the plate relative to at least one staging location in the process workflow;
• and a process controller, the process controller connected to the transporter, to the at least one sensor, and to a computer processor;
• (b) sensing, with the at least one sensor, location and orientation of a plate to be transported;
• and
• (c) using the transporter, lifting the plate in a Z direction relative to an XY plane and one or more of:
• moving the plate in an X direction, moving the plate in a Y direction, and rotating the plate relative to a Z-axis;
• wherein the at least one sensor comprises a contrast sensor configured to detect a difference in reflection characteristics of an object at a given wavelength or range of wavelengths, the at least one staging location comprises a planar surface having at least portions thereof having reflection characteristics that differ from the reflection characteristics of the printing plate to a degree detectable by the contrast sensor, and the method comprises the sensor detecting an edge of the plate relative to the planar surface of the staging location.

A plate handling system for transporting printing plates between workstations in a process workflow, the system comprising:

• a plurality of vacuum gripper end effectors configured to grip the printing plates and mounted to a computer controlled transporter, the transporter configured to translate in at least three orthogonal directions and to rotate about at least one rotational axis;
• at least one sensor for detecting orientation of the plate relative to at least one staging location in the process workflow;
• a controller, connected to the transporter and the at least one sensor, configured to cause the transporter to move based upon programmed instructions in accordance with information provided by the sensor;
• wherein the at least one staging location comprises a mobile preparation table configured to transport printing plates to and from the staging location, the mobile preparation table comprising:
• a base having a frame and a plurality of wheels attached to the frame and configured to roll along a floor surface;
• a planar preparation surface having a frame pivotally attached to the frame of the base;
• one or more physical connection interfaces configured to secure the base mechanically in a fixed position in the staging location;
• and
• a processor with a communication interface configured to exchange information between the mobile preparation table and the plate handling system.

A plate handling system for transporting printing plates between workstations in a process workflow, the system comprising:

• a plurality of vacuum gripper end effectors configured to grip the printing plates and mounted to a computer controlled transporter, the transporter configured to translate in at least three orthogonal directions and to rotate about at least one rotational axis;
• at least one sensor for detecting orientation of the plate relative to at least one staging location in the process workflow;
• and
• a controller, connected to the transporter and the at least one sensor, configured to cause the transporter to move based upon programmed instructions in accordance with information provided by the sensor;
• at least one thickness detector configured for measuring thickness of a printing plate relative to a surface of the plate handling system, the surface defining an X-Y plane for receiving the printing plate, the thickness detector comprising:
• a sensor positioner controllable in at least Y and Z axes disposed above the surface;
• a non-contact distance measurement sensor mounted on the positioner and configured to output a measurement signal indicative of distance along a Z axis perpendicular to the X-Y plane;
• a processor configured to control the positioner and to receive a measurement signal from the sensor, the processor programmed with instructions for:
• (a) receiving information defining X-Y dimensions and expected location of the plate;
• (b) moving the positioner to a first position disposed above a point on the surface not above the expected location of the printing plate;
• (c) obtaining a reference Z-distance measurement signal from the sensor for use as a reference Z-distance between the sensor and the surface;
• (d) moving the positioner to a second position disposed above a point on the surface above the expected location of the printing plate;
• (e) obtaining a second Z-distance measurement signal from the sensor and processing the second Z-distance measurement signal and the reference Z-distance measurement signal to obtain the measured thickness of the printing plate.

A method of processing a printing plate in a plurality of workstations in a process workflow, the method comprising the steps of:

• (a) providing a plate handling system for transporting the printing plate from one workstation to another in the process workflow, the plate handling system comprising a computer controlled transporter configured to translate in at least three orthogonal directions and to rotate about at least one rotational axis, end effectors for gripping the printing plates connected to the transporter, at least one sensor for detecting orientation of the plate relative to at least one staging location in the process workflow;
• and a process controller, the process controller connected to the transporter, to the at least one sensor, and to a computer processor;
• (b) sensing, with the at least one sensor, location and orientation of a plate to be transported;
• and
• (c) using the transporter, lifting the plate in a Z direction relative to an XY plane and one or more of:
• moving the plate in an X direction, moving the plate in a Y direction, and rotating the plate relative to a Z-axis;
• wherein the end effectors are configured to grip the printing plate on an upper surface of the plate, and the method comprises applying an image to the upper surface of the plate at an imaging station, and irradiating both the upper surface and an opposite lower surface of the plate at a photopolymer curing station, including curing the photopolymer plate using actinic radiation emitted from radiation sources mounted on a linear stage having a resting location relatively nearer a trailing end of the curing station than to a leading end of the curing station, and pulling the plate onto the curing station in a direction from the leading edge to the trailing edge using the transporter, depositing the plate in a curing location, and the transporter returning to a location that does not interfere with transit of the curing station linear stage.