Rotary coater with coating element that substantially maintains speed during use, and device for the additive manufacture of an object using the rotary coater

An apparatus for applying successive layers of powder material in a build field of a device for additive manufacture of an object, comprising:

• a support to which is coupled a coating element having a length extending in a longitudinal direction over the build field, the coating element being adapted to move and thereby smooth a layer of powder supplied to the build field over the build field in the course of additive manufacture;
• the support being mounted so as to rotate about an axis where the axis is perpendicular to a plane defining the build field, with the coating element moving over the build field from a first edge of the build field to a second edge of the build field, the coating element being coupled to the support during a rotational motion of the support within the build field;
• a compensation mechanism communicating with the coating element, the compensation mechanism including at least a first guide plate having a first guide profile and at least a first force-transmitting element having a first sliding element which are guided on the support such that, during the rotational motion of the support, the first sliding element of the first force-transmitting element slides on the first guide profile, moving the coating element relative to the support so as to maintain the coating element in a straight movement path relative to the build field without movement of the coating element in the longitudinal direction during the rotational motion of the support within the build field.