Patent ID: 8070156
Filing Date: 2011-12-06
Classification: B65H

Abstract:
1. A sheet adsorption device comprising: a sheet adsorbing surface; a suction hole disposed on the sheet adsorbing surface; and a negative pressure generating unit that applies a suction force on the sheet; a communication flow path that extends from the suction hole to the negative pressure generating unit; a flow path shifting unit that shifts between a first state and a second state of the communication flow path in accordance with existence of a sheet that covers the suction hole, wherein a suction force of the suction hole in the second state is smaller than that in the first state and wherein the communication flow path is not closed in the second state; wherein the communication flow path includes a first flow path part that is opened and shut by a valve and a second flow path part that is always open between the suction hole and the negative pressure generating unit, wherein the valve is disposed between the suction hole and the negative pressure generating unit and wherein the valve opens and shuts according to a difference in pressure between the communication flow path on a suction hole side of the valve and the communication flow path on a negative pressure generating unit side of the valve, wherein the second flow path part comprises a portion of the valve and a contact surface of the communication flow path which comes into contact with the valve when the valve shuts, wherein the valve comprises a plate-shaped member and is supported on both sides in a direction that is approximately perpendicular to at least one direction by a support part that is supported on both sides in at least the one direction by a base body of the plate-shaped member, and wherein the second flow path part is a through hole configured to the plate-shaped member forming the valve.