Harry C. Hagman, CDT
The Hagman Balancer Company, Minneapolis, MN.
The "Special Deluxe Balancer Model R" articulator was essentially the "Deluxe Balancer" with additional special features. The Model R featured an adjustable "functioning head" and an "extended hinge axis." The "functioning head" was horizontally adjustable in an A-P direction and the "extended hinge axis" was an axle extending laterally from the posterior hinge position. These features were provided the use of a facebow and hinge axis locator. The various attachments that were provided for the "Special Deluxe Balancer Model R" were the Occlusal Arc Guide, the Flat Plane Guide, the Occlusal Level and Mounting Jig, the Natural Path Recorder and Gothic Arch Tracing Device, a Mechanical Incisal Guide Table, Hinge Axis Locator and the Clasp Surveyor.
The "Balancer" articulators were designed according to Monson's "Spherical" theory of mandibular movement. Hagman believed that the mandible functioned in an arc from centric relation and that all movements can be produced in an articulator functioning from a single point of rotation. The operating mechanism of the "Balancer" articulators was a single ball and socket (universal) joint call the "functioning head" located 4 inches directly above the occlusal plane. The hinge joint of the "Balancer" is located to be "in line" or concentric to the occlusal path.
Dr. Edgar N. Starcke's articles in the Journal of Prosthodontics have more information on the history of articulators.