Memory mechanism

In a memory mechanism for controlling change of informations in a plurality of information systems each including information to be incrementally changed and indicated in succession, the improvement which comprises actuation means adapted to be actuated in response to a predetermined input signal whenever said actuation means receives such a signal, a first memory wheel operated by said actuation means to incrementally change the informations in the first system of said information systems until a cycle of incremental information change is completed and having an intermittent transmission means, a first transmission wheel for engaging said intermittent transmission means to be operated thereby, a second memory wheel including a second transmission wheel engaging said first transmission wheel to be operated thereby and adapted to incrementally change the informations in the second system of said plurality of information systems each time said first memory wheel has made one complete rotation so as to complete a cycle of incremental information change each time said second memory wheel makes one complete rotation, a first camming portion formed in at least one selected position of said first memory wheel, a second camming portion formed in at least one position of said second memory wheel, lever means urged to act on said first and second memory wheels and adapted to be operated during the lever is in engagement with both said first and second camming portions and operation means operatively connected to said lever means to operate said first memory wheel to allow the first memory wheel to effect incremental information change in said first information system during said lever means is operating independent of said input signal whereby incremental change of the informations in the first information system is controlled.