A device for introducing values into a calculating machine has a simplified keyboard with only 10 keys, each bearing a different digit. A control member is connected to each of the keys and a positioning member is connected to one end of the control member. A side plate follows the movement of the control member and has a retaining member on one end. Two shafts parallel to each other are mounted on the device, and a registering device with movable teeth is loosely mounted on one of the shafts for movement lengthwise of the shaft. A rack bar engages with one end of the registering device and extends in the direction of the associated shaft. An escapement member is rigidly mounted on the other shaft and engages with the rack bar to limit the movement of the registering device. The escapement and the retaining member cause the stepwise advance of the intermediate registering device. The positioning member is placed in the path of the movable member corresponding to the control member of the depressed key during the movement of the registering device lengthwise of its associated shaft. As a result, the movable member is displaced from its rest position into its operating position upon that movement of the registering device.
