Grinder for grinding a product in beans, particularly for a beverage vending machine

A grinding apparatus for grinding a product in beans, for a beverage vending machine, the grinding apparatus comprising;

• a grinder with an attachment frame, an inlet for a product in beans to be ground, a movable grinding member for grinding the product in beans;
• an electric driving motor for driving the movable grinding member;
• an outlet for a ground product;
• and
• a doing device for dosing an amount of ground product supplied by the grinding apparatus;
• wherein the dosing device comprise a measuring device comprising a guide channel communicating with said outlet and configured to form and advance a uniform flow of ground product in a supply direction, and at least one wheel partially housed in said guide channel and coupled to said attachment frame to freely rotate about an hinge axis transverse to said supply direction under the thrust of said ground product flow;
• wherein the measuring device further comprises an electronic sensory system for sensing, and outputting an output signal indicative of, an angular position of the wheel about said hinge axis during the flow of the ground product so as to allow an electronic control unit to compute the amount of ground product flowing through said outlet based on said output signal.