Automatic Musical Company
Roll Mechanism

(Photograph courtesy of Terry Barnes)

Overview of an early Automatic Musical Company endless music roll mechanism (Mandolin Piano, Haddorff #27096). The wooden tracker bar is fastened to a floating cast iron framework and is located at the right hand side of the piano under the keybed, and in front of the pneumatic stack. Here the bulky music roll bin, with drive and guide rollers at the top side, has been moved out of the way to reveal the tracker bar arrangement. Rubber tubes from nipples on the back side of the tracker bar were routed to the various unit valve assemblies on the main stack, and/or to separate valve units controlling the sustaining and soft piano pedals, and the motor cut-off switch device.

(Photograph courtesy of John Rutoskey)

Looking up at the tracker bar assembly in Automatic Reliable Self-Playing Piano #20269. Here the case bottom board is in place, as is the molded wood cover (at picture far left) that conceals the stack (which protrudes out and over the bottom board) and runs right up to the edge where the roll bin would normally be located. The wooden tracker bar is fastened to the front of a floating stamped metal framework hinged at its back side. A short length of fine wire chain near the middle of the tracker bar limits the downward travel of the framework and any attached components. To the right of the tracker bar is a wooden speed or tempo control pulley with a length of round leather belting firmly secured in the pulley's grove, which in turn rides against a cast iron friction disk that is belt driven from the backside of the vacuum pump. The horizontal position of the speed control pulley in relation to the friction disk determines the speed or tempo of the music roll, its position manually controlled by the flat steel lever that protrudes over the top side of the tracker bar. This tempo control pulley is attached to a metal shaft that runs behind the tracker bar to a small pinion gear set in a bearing at the left side of the tracker assembly. When the music roll bin in slid into place this pinion gear engages a mating gear on the music sheet drive roller located at the top of the music roll bin.

(Photograph courtesy of Terry Barnes)

Side view of the tracker bar assembly in Automatic Mandolin Piano #27096. This view makes it clear that the tracker bar and the tempo controls are mounted in two different frameworks. The tempo control wheel and friction disk are mounted on one end of a sturdy cast iron framework, with the small mating pinion gear (picture foreground with a circular guide flange behind it) for the music roll drive spool on the other end. The tracker bar is mounted into its own stamped metal framework. Notice that the downward pointing bearing post in which the small pinion gear is held (picture foreground) has a swivel point with the movable lower part spring loaded. This allows the pinion gear to engage the gear on the music roll drive roller, with the spring tension keeping the gear firmly mated. For some unknown reason someone has crudely chiseled a gaping hole in the keybed over the tracker bar area. Rubber tubing from the tracker bar is inserted into drilled ports in its backside, giving adequate room for the tubing without the need to gouge out part of the keybed and exposing the underside of the keys, as is shown in the previous picture above.

(Photograph courtesy of Terry Barnes)

Front view of the detached music roll bin for Automatic Mandolin Piano #27096. After changing a music roll, the detached bin can easily be slid back into its guiding cast iron channel blocks located under the keybed. When this is done, the tracker bar will ride gently up and over the rear felt covered roller and then drop down into the valley formed between the two rollers, thereby forming an air tight seal between the paper and tracker bar.

(Photograph courtesy of Terry Barnes)

Side view of the detached music roll bin for Automatic Mandolin Piano #27096. At the top the flat metal strips that act as guide rails are visible. These rails slip into cast iron channels screwed to the underside of the keybed, which keep the bin in place and properly aligned when in use. Notice the large rectangular cutout on the facing upper wooden panel, which allows the bin to fit around the tempo control wheel and friction disk assembly. Looking through the cutout one end of the spring loaded pinch roller is visible at the right bottom of the cut out portion. The slanted notches near the top of the unit are for inserting the crank end of a music roll rewinding spool. The opposing or far side of the bin has matching drilled holes in which to accommodate the other end of the rewinding spool.

(Photograph courtesy of Terry Barnes)

Top rear view of the detached music roll bin with the wooden rollers in place for Automatic Mandolin Piano #27096. The spring loaded pinch roller (with the two green felt strips) is at the back side of the bin (but front and center for this photograph). The next roller is covered with blue felt and is gear driven. It, in conjunction with the pinch roller, pulls the music roll through the roll mechanism. The rear roller is a guide roller and it is free spinning. The blue felt covered drive roller and the free spinning guide roller rest in a metal framework that can be easily disengaged from the bin and removed for inserting and/or changing a music roll.

(Photograph courtesy of Terry Barnes)

Top side view of the detached music roll bin for Automatic Mandolin Piano #27096. The front of the bin is at picture right, and this view clearly shows the slanted notch used for the crank end of the music roll rewinding spool. The simple hook is lowered over the spool's shaft to keep it seated in the notch when using the hand crank.

(Photograph courtesy of Terry Barnes)

Top view of the removable drive and guide rollers from the top of the music roll bin for Automatic Mandolin Piano #27096. Both rollers lift out together and are integral to a sturdy metal framework that is securely locked in place at the top of the roll bin when in use.

(Photograph courtesy of Terry Barnes)

Bottom view of the removable drive and guide rollers from the top of the music roll bin for Automatic Mandolin Piano #27096. Both rollers lift out together and are held in a sturdy metal framework that is securely locked in place at the top of the roll bin when in use. The purpose of the rectangular plate may be to prevent the music roll from bunching up and jamming between a roller and the tracker bar, insuring that the paper falls away and into the bin.

(Photograph courtesy of Terry Barnes)

Top front view of music bin pinch roller for Automatic Mandolin Piano #27096. The pinch roller is mounted in the same sturdy cast iron framework that supports the removable roller assembly, and it pivots on a rod at its bottom side. The top side is spring loaded to push the pinch roller toward the felted drive roller, using a flat metal spring similar to a piano pedal spring.

(Photograph courtesy of Terry Barnes)

Looking down from the top into the empty roll bin for Automatic Mandolin Piano #27096. The (approximately 3/4 inch diameter) nickel plated steel rod with chamfered ends and that is laying crosswise on the top edge of the music bin is meant to be inserted through the endless loop of the music roll and allowed to rest at the bottom of the music roll bin. This helps to insure that the music roll always feeds from the bottom of the bin.

(Photograph courtesy of John Rutoskey)

Top view of the music roll transport rollers for an Automatic Musical Company Reliable Self-Playing Piano #20269. Notice that the pinch roller in this example is fully covered with green felt, as opposed to what is thought to be a later incarnation (as picture in the above Mandolin Piano examples) with the pinch roller having only two narrow strips of felt.

In this photograph the blue (purplish looking) felted spool is the drive spool (early versions of this mechanism had rubber-covered spools, like a typewriter platen), and has a gear on the edge of one of the flanges that meshes with a pinion gear mounted on the underside of the keyboard of the piano. The green felted roller is a spring-loaded pinch roller that presses along the entire length of the drive roller. The other plain wooden spool (early versions of this mechanism felted this spool also, but later ones the spool was plain wood, as shown here) is free in its bearings, and acts to guide the paper up from out of the bin below as it is pulled across the tracker bar, which is mounted under the keyboard of the piano as well, and drops down in between the two spools automatically when the bin is slid into place. At the same time, the pinion gear meshes with the drive gear, and the music roll begins to move up and out of the bin, across the tracker bar, and back down the other side of the bin.

(Photograph courtesy of John Rutoskey)

Top left side close-up of drive roller with a music roll installed in Automatic Reliable Self-Playing Piano #20269. The drive gear for the music roll drive roller is clearly visible at picture center. The engages with the pinion gear mounted below the keybed and to the left of the tracker bar..Here a music roll is shown installed, and held firmly in place by the pinch roller and also drooping loosely over the guide roller and into the music roll bin. The hole in the wood side board over top of the paper drive roller is where the loose flange side of the rewinder spool shaft is inserted during use. The crank end slips into a slanted notch on the other side of the roll bin.

(Photograph courtesy of John Rutoskey)

Changing a music roll in Automatic Reliable Self-Playing Piano #20269. To change a roll in the Reliable the assembly holding the two spools has to be slid out of the mounting casting, and out of the way of the music roll. It is a very compact and well-designed device. Pushing the entire roller assembly toward the spring-loaded pinch roller will free it from a pair of retaining blocks, and then lift it up and out. It can then be slid out sideways, carefully avoiding tearing the music roll loop.

The pinch roller is spring loaded with a very heavy piece of flat spring steel, similar to a piano pedal trap spring, and is located about halfway across the main pinch roller casting. While the roll carriage mechanism is out of the bin, a chain limits the pinch roller's travel, so that it will not fall way down into the bin and possibly damage the music roll.

On the top edges of side walls of the bin, and exactly in the same manner as the later Link pianos, one side has a notch and hook setup. The other side of the bin wall just has a small hole. After removal of the roll carriage spool assembly, the rewinder device is put in place in exactly the same manner as a regular Link piano, the hook is placed over the shaft to keep the rewinder in place during use, and the roll is rewound and removed.

(Photograph courtesy of John Rutoskey)

Music roll rewinder drawing from Patent No. 795,278, filed January 29, 1904, by Frederick R. Goolman, the mechanical genius behind many of the mechanisms used by the Automatic Musical Company. The wooden flange at the left (non-crank end) is removable, whereupon a loop of music roll paper can be slid between the wood core and metal rod. Then the removable flange is replaced and the rewinder is set into the drilled hole and slanted slot of the top of the music roll bin and the music roll is rewound.