Four-ball wear scar measuring device

The utility model relates to a four-ball wear scar measuring device, which belongs to the technical field of friction testing machine. In order to solve the technical deficiency that the existing four-ball wear scar measuring device used cannot guarantee that observing axis of a lens cone is vertical to a plane of the wear scar easily, the utility model provides the four-ball wear scar measuring device to guarantee that observing axis of the lens cone is vertical to the plane of the wear scar without adjusting the included angle between the lens cone and a work table. The lens cone of the four-ball wear scar measuring device can be fixed on a lens cone moment arm through a sliding rail capable of sliding up and down, and the axis of the lens cone forms an included angle of 54.74 degrees with the work table. An oil box of the four-ball wear scar measuring device is fixed on the work table capable of rotating horizontally through a positioning pin.