Device and method for placing plate-like elements in a processing machine

1. A method for placing plate-like elements within a processing machine, wherein the machine comprises a feeder for placing the plate-like elements, and a plurality of grippers of a conveyor in which the elements are placed by the feeder, the conveyor conveying the elements in a paced flow to successive stations, the feeder having a gripper, the feeder being driven by a computation and control unit;

the method comprising the successive steps of:

advancing the plate elements in a downstream direction; and

during the advancement of each plate-like element:

measuring a longitudinal placement error and an angular placement error of the plate-like element at the same time relative to a theoretical position, by detecting at least one of a front edge or a rear edge of the plate-like element by at least two sensors, at least one sensor being located in a first lateral direction relative to the downstream direction and at least one sensor being located in a second lateral direction relative to the downstream direction, the second lateral direction being in an opposite direction from the first lateral direction;

controlling the feeder according to the measured longitudinal placement error and the measured angular placement error;

then activating the gripper of the feeder to attach the plate-like element to the feeder;

then measuring the longitudinal placement error, a transverse placement error and the angular placement error of the plate-like element then attached to the feeder, relative to a theoretical position, by detecting register marks printed on the plate-like element; and

controlling the feeder according to the measured placement errors of the plate-like element to which the feeder is attached.

2. A machine for processing plate-like elements comprising:

a conveyor for conveying a plurality of plate-like elements in a longitudinal direction, the conveyor having a plurality of grippers;

a feeder including a gripper for placing the plate-like elements in the plurality of grippers of the conveyor, the conveyor conveying the plate-like elements in a paced flow into successive stations;

a lateral linear motor configured and capable of moving the feeder in a lateral direction relative to the longitudinal direction;

two longitudinal linear motors configured and capable of moving the feeder in the longitudinal direction;

at least three first sensors configured and capable of measuring light intensity first reflected by a surface of the plate-like element;

a computation and control unit receiving measurements from the first sensors and controlling the lateral linear motor, the longitudinal linear motors and the gripper of the feeder; and

at least two second sensors configured and capable of detecting the passage of a longitudinal edge of the plate-like element while the plate-like element is in motion before the plate-like element is gripped by the gripper of the feeder and configured and capable of detecting a longitudinal placement error and an angular placement error of the plate-like element at the same time relative to a theoretical position; the second sensors being placed upstream in the longitudinal direction of the first sensors, and being connected to the computation and control unit; at least one sensor of the second sensors being located in a first lateral direction relative to the longitudinal direction and at least one sensor of the second sensors being located in a second lateral direction relative to the longitudinal direction, the second lateral direction being in an opposite direction from the first lateral direction.

3. A machine for processing plate-like elements according to claim 2 , wherein the second sensors detect the passage of the front edge of the plate-like element.

4. A machine for processing plate-like elements according to claim 2 , wherein the second sensors detect the passage of the rear edge of the plate-like element.