Shaft device for a bellows-type gas meter

A shaft device for a bellows-type gas meter comprising:

• a shaft having an axis,
• a first eccentric cam assembly coupled to the shaft and having a centerline,
• a second eccentric cam assembly configured for placement on the shaft and having a centerline,
• the centerline of the first eccentric cam assembly and the centerline of the second eccentric cam assembly placed on the shaft mutually defining an angle,
• an element coupled to the shaft, the element having a radial groove therein,
• an opening defined in the second eccentric cam assembly, the opening having an axis parallel to the axis of the shaft,
• a rotatable insert element configured for insertion in the opening,
• a follower means provided on the insert element for engaging the radial groove, the follower means having an axis parallel to the axis of rotation of the insert element, and
• a radial protrusion for axially locking the shaft by rotating the insert element,
• whereby the angle between the centerline of the first eccentric cam assembly and the centerline of the second eccentric cam assembly placed on the shaft is adjustable by rotation of the rotatable insert element.