Zero-reset type counter

DETAILED DESCRIPTION The primary object of the present invention is, in view of the above mentioned circumstances, to provide a zero reset type counter so formed as to be easy to assemble and apt for a mass production and of which the order shift pinion group is entirely housed inside the digit wheels.
According to the present invention, this object is attained by forming an annular recess having an internal gear on one side of each digit wheel and an annular recess having order shift teeth and an eccentric cam on the other side, arranging each digit wheel rotatably on a common supporting shaft so that the above mentioned recesses are respectively facing to each other, interposing between two adjacent digit wheels a zero reset lever fixed on a rotary shaft disposed adjacent to the digit wheel group and able to forcibly return each digit wheel to the zero indicating position through making a contact with the above mentioned eccentric cam, pivoting a pinion to mesh with the above mentioned internal gear on one side of said zero reset lever and an order shift pinion to mesh with the order shift teeth on the other side so that they are rotatable integrally with each other and housing them inside the space formed by the above mentioned recesses.
According to a preferable formation of the present invention, the order shift teeth are consisting of two driving teeth and a pair of regulating teeth adjacent to the driving teeth, an idling face and a controlling face intersecting thereto at right angles are formed along the inner circumference between the pair of regulating teeth on each digit wheel, the teeth of the order shift pinions are so thinly formed as to be able to be placed on the above mentioned idling face every other piece and the tops of the pair of teeth adjacent to the thin teeth of the order shift pinion are so formed as to be able to be engaged with the above mentioned controlling face except at the order shift.
The zero reset lever is selected to have such a thickness as to be able to fill up the gap between a pair of digit wheels adjacent each other