Serial printer

A serial printer including:

• a carriage movable along a line to be printed and carrying a type wheel formed by a disc-shaped member having a plurality of apertures spaced circumferentially around the outer portion thereof, said type wheel further including a plurality of respective dome members each covering a respective aperture and formed of a resilient material enabling each dome member to be deflected inwardly toward the respective aperture by a snap action substantially instantaneously upon application of a sufficient pressing force and then to be returned to its initial position by its resilience, and a plurality of type elements each fixed to the inner surface of a respective dome member and movable out of the plane of said disc-shaped member upon inner deflection of the respective dome member;
• means connected to said type wheel for rotating it to bring a selected type element into a printing position;
• means for moving said carriage along the line to be printed;
• a hammer member held pivotally to said carriage, and means for pivoting said hammer member to cause it to apply said pressing force.

A serial printer including:

• a carriage slidable along a first rotary shaft extending parallel to a line to be printed and carrying a type wheel having a plurality of type elements;
• means interconnecting said type wheel and said first rotary shaft for rotating said type wheel to bring a selected type element in a printing position;
• a hammer member held pivotally to said carriage, and means for pivoting said hammer member to cause it to apply a pressing force to the selected type element, said pivoting means including a fixed cam member extending along the entire line to be printed and adapted to be rotated about an axis parallel to the line to be printed and means including a hammer drive shaft to rotate said cam member for applying said pressing force regardless to the position of said carriage along the line to be printed;
• means for moving said carriage along said line to be printed;
• a motor;
• and
• means including a clutch mechanism operated by a solenoid to end the rotation of said first rotaty shaft to bring the desired type element in said printing position while rotating said cam member to apply said pressing force by said hammer member and then actuate said carriage moving means.