Assembly for a detachable connection for a printing element in an electric office machine

Claim 1

In an electric office machine provided with an electric motor in a printing unit having a print element, the improvement comprising an assembly for detachable connection of said print element to the shaft of said electric motor, a platen, a carriage mounting said printing unit for movement along said platen, said print element being disc-shaped having radially extending arms carrying characters thereon, means mounting said carriage for movement together with said printing unit along said platen, said printing unit being mounted to be movable on said carriage between a printing position and a loading position, a dog member, a spring loaded retaining means, said print element being biased against said dog member, the latter being secured to said motor shaft by said spring loaded retaining means, said retaining means being operated to release said print element for replacement by a fixed surface on said carriage engaging said retaining means when said printing unit is moved to a loading position, and wherein said retaining means comprises a fixing plate supporting said print element for movement along said motor shaft between a first position outside the end of said motor shaft in which the print element is released for replacement by a movement which is in a direction transverse relative to said motor shaft, and a second position in which the print element is secured for movement with said motor shaft, and a spring-loaded operating member, said fixing plate being operated to release said print element by said spring-loaded operating member engaging said fixed surface on said carriage.