(Photograph courtesy of Dick Hack.)

Retrofitted Automatic Whippet Race diorama in National piano #7352. At race track left the Whippets are lined up at the starting point, ready to race. The finish gate is at the right end of the track. When the nose of a Whippet pushes on the finish gate the race is immediately terminated, and the race mechanism is disengaged. Motive power must be applied to the race mechanism to either reset an old and finished race, or to initiate a new race, i.e., the electric motor must be powered on. To reset an old and finished race the Reset—Race control lever (at the lower right of the front panel window) must be held in the left side Reset position until the reset process is completed. This reset action (1) releases the locking pawls that hook into the toothed rim on each of the Whippet drive pulleys, and (2) engages the worm gear jaw clutch for the shaft that rotates the four Whippet drive pulleys. And during the Reset non-race mode operation the starting gate (underneath the right end of the race track) is, by default, latched in its upward closed position. With the starting gate shut, the nose of each Whippet will eventually bump up against the gate and stall, going no further, with the friction shoes inside its drive pulley safely slipping. There are two Whippets mounted equidistant on each steel belt, so that when four hidden Whippets are nosed against the starting gate, the other four Whippets are also lined up, but visible at the left side of the race track. Once the Whippets are lined up, the Reset lever can be released back to the neutral center point, or it can be moved momentarily to the full right Race position to initiate a new Whippet race.

(Photograph courtesy of Dana Johnson.)

Mechanical drive system for the Automatic Whippet Race diorama in a National coin piano (serial number unknown). The race diorama is mounted on top of the National built stack, with the mechanical motive power delivered by means of a chain and sprocket affixed to the end of the horizontal drive shaft (at photograph right). On the left end of this drive shaft is a worm gear arrangement that can be engaged and disengaged from the drive shaft using a simple but effective jaw clutch. Below the race diorama, and on top of the stack cover, is a partially visible wooden strip of pallet valves that are used to randomize a signal output based upon what piano notes are played. The curved wooden structure to the right of the Whippet race diorama is the coin transfer connector between the coin slot faceplate and the coin switch mechanism.

(Photograph courtesy of Dick Hack.)

Whippet race drive pulleys in National piano #7352. This view of the four Whippet race drive pulleys clearly shows the steel bands (that disappear under the white finish gate with its bright red side posts) and upon which are fastened the Whippet hounds. (Copper bands have been reported in pianos #240 and #794.) The individual locking pawls that stop the rotation of a drive pulley grab onto the jagged teeth located around the rim of each pulley. The brass worm gears at left rotate the shaft on which the pulleys ride. Inside each pulley is a pair of friction shoes that ride against the inside circumference of the pulley, and safely slip whenever the movement of a Whippet is blocked, such as when reseting a race and the hounds line up against the starting gate.

(Photograph courtesy of Dick Hack.)

Front view of the Whippet drive pulleys and associated reset levers in a National coin piano (serial number unknown). The three levers labeled "a," "b," and "c" together make up the so-called reset levers, which are connected at the top end by a common horizontal bar so that all three act simultaneously. Lever "a" is connected to a bent metal bar (the lock override bar) that acts to override and release all of the locking pawls, thereby allowing the Whippet drive pulleys to rotate without restriction. Lever "b" causes the jaw clutch on the worm shaft to become engaged, powering the Whippet drive pulley shaft. Lever "c" has an outward projecting flange that makes contact with the upper part of the vertical lever arm connected to the Reset—Race knob, so that when the knob is moved to the Reset position the lever arm pushes lever "c" to the right. This action puts the race mechanism into the "reset" mode—necessary for aligning the four hounds in the start position. The knob must be held in the Reset position until all four Whippets are visible and stopped, with their noses lined up in the starting position.

(Photograph courtesy of Dick Hack.)

Side view of the worm gear drive and the associated race lever in National piano #7352. Above the worm shaft is the reset lever "c," which when pushed to the right puts the race mechanism into the Reset mode. Below the worm shaft is the L-shaped play lever "d," which, when the flanged part (on the lower vertical leg of the L-shaped lever) is pushed to the right, puts the race mechanism into Race mode. In this photograph the jaw clutch on the worm shaft is shown in the engaged position, with the bottom of lever "b" positioned as though a race was currently in progress. When a Whippet encounters the finish gate a pallet valve is opened that causes the pneumatic at picture right to instantly collapse, it then pushing the bottom of lever "b" to the left, which disengages the jaw clutch, stopping the worm gear drive and any further race activity. Simultaneously, when lever "b" is pushed left far enough, the race lever "d" snaps upward, capturing the forward facing pin on lever "b," thereby holding the jaw clutch in the disengaged position. As a consequence, the race mechanism become inactive, until someone deliberately takes action, such as resetting the race hounds for a new race.

When the Reset—Race knob is moved to the Race position, the lower part of its attached lever arm pushes against the raised flange on the lower vertical leg of race lever "d," pushing it to the right. This action causes the locking notch on the horizontal part of the race lever arm to move downward, releasing the hold on lever "b," closing the jaw clutch. At the same time, The horizontal end of the race lever "d" pushes down on the right end of the starting gate latch lever "e," pivoting the latch hook on its opposite left end upward. Raising the hook on lever "e" unlatches the starting gate, so that the hounds can push through it and race onward toward the finish gate. Then, once the Reset—Race knob is returned to the neutral center position, the starting gate latching lever "e" settles back into a position whereupon it is able to lock the starting gate, but this locking event cannot occur until all of the Whippets have finished passing through the starting gate, so that the gate can return to its default upright position and be locked shut.

(Photograph courtesy of Dick Hack.)

Whippet race drive pulleys and locking pawls in National piano #7352. The four locking pawls pivot on the most forward upright shaft, which has the round metal spacers separating the individual locking pawls. Each locking pawl has an attached coil spring that pulls the pawl tip into the toothed perimeter of the Whippet drive pulleys. Thus, by default, the drive pulleys are locked and prevented from moving the hounds. The four metal rods trailing off the left side of the photograph would normally be connected to smallish pneumatics underneath the race track. Pulling on a wire rotates the locking pawl away from the toothed drive pulley, allowing the drive pulley to rotate only while the rod is keeping the locking latch away from the drive pulley. The "unlocking" pneumatics are activated through a "randomizing" system that causes each Whippet to independently move forward in random spurts that cannot be predicted. The lock override bar, labeled "a," is bent in such a way that it acts as a lever that when rotated pushes all four locking pawls back away from the toothed Whippet drive pulleys during the reset process. In the 2nd image above this picture, titled Front view of the Whippet drive pulleys and associated reset levers, the reset lever "a" is what controls the position of the lock override bar "a" shown in this photograph.

(Photograph courtesy of Dick Hack.)

Locking pawls and the lock override bar in National piano #7352. This view shows the working end of the individual locking pawls, the tip end that actually engages the toothed rim of a Whippet drive pulley. The lock override bar, labeled "a," is used to push back all four of the locking pawls during the reset process, allowing all four Whippet drive pulleys to rotate without restriction. The larger diameter upright shaft at picture right is the spindle that holds and rotates the Whippet drive pulleys. The four wires trailing off at picture left are hooked onto the locking pawls, and when pulled by control pneumatics they rotate the tip of the locking pulley away from the toothed rim of the Whippet drive pulleys.

(Photograph courtesy of Dick Hack.)

Whippet race idler pulleys in National piano #7352. The four idler pulleys are located at the left end of the race track. The rounded flat sheet metal guides that hold the actual pulleys are tear shaped, with the narrow end (not visible) fitted with a bearing upon which the pulley unit can swivel. The coil springs serve to keep a constant tension on the steel bands that go around each of the four independent pulleys, applying enough tension to keep the bands from slipping on the Whippet drive pulleys located at the opposite right-hand end of the race track.

(Photograph courtesy of Dick Hack.)

Head-on view of a Whippet race idler pulley. The idler pulley rides on a center hub attached to the backplate, which swivels on a shaft at its narrow end. The tiny hole for the coiled tensioning spring is at about the 7:30 o'clock position just off the edge of the pulley. Darkened trails of dried lubricant can be seen where the steel bands enter and exit the pulley circumference.

(Photograph courtesy of Dick Hack.)

Upside down Whippets passing through the starting gate in National piano #7352. In this picture only two upside-down Whippets are visible, with the tail end of the lagging hound still dragging itself through the starting gate (labeled "g"). The two-level starting gate extends across the entire width of the race track. Only the hook end of the starting gate latching lever "e" is visible. Below it, at label "f," is the lower shoulder of the starting gate that is caught by the latching lever "e" when the metal blade that is the starting gate returns to its upright position. The higher portion of the starting gate "g" interacts with the Whippets, blocking them from further movement during the reset process when the Whippets are being lined up at the starting point for the next race. Then, when the race mechanism is first put into the race mode, the starting gate is unlatched and the Whippets immediately start pushing through the light spring tension holding the starting gate closed, keeping the gate at least partially open until the tail end of the slowest hound is all the way through. Once the hounds are past the starting gate there is nothing to keep it open, and so the light spring tension snaps it shut in its normal upright position, whereupon the starting gate latching lever "e" keeps it latched shut until the next race is initiated. The control pneumatic with the purple rubber cloth covering is the closest of four to the starting gate and the Whippet drive pulleys, and is used to retract a locking pawl for one of the drive pulleys.

(Photograph courtesy of Dick Hack.)

Starting gate and its pallet trip port in National piano #7352. The white colored finish gate is free to swing to the right whenever the nose of a Whippet hound pushes up against it. On its right side there is an extension that seals the opening in a hollow brass elbow (which is painted black). When the finish gate swings forward the end of the elbow is no longer blocked, and atmospheric pressure rushes in. The elbow is connected to a valve underneath the race track, which then opens and exhausts the air within the pneumatic that, in turn, disengages the jaw clutch on the worm shaft, instantly stopping any further race activity. A portion of the toothed rims on the Whippet drive pulleys are visible behind the finish gate.

(Photograph courtesy of Dick Hack.)

Back side of the "Reset—Race" control lever in National piano #7352. The vertically oriented lever arm is securely attached to the Reset—Race knob on the piano's upper front panel. The upper forward-bent part of the lever pushes against the flanged surface of reset lever "c," as shown in the above image titled Front view of the Whippet drive pulleys and associated reset levers. The lower forward-bent part of the lever pushes against the flanged surface on the lower vertical leg of the L-shaped race lever "d," as shown in the above image titled Side view of the worm gear drive and the associated race lever. The metal work partially visible at left is a bottom corner of the coin slot faceplate, and the window molding at right holds the front glass window in place.

(Photograph courtesy of John Perschbacher.)

Directions for operating the Automatic Whippet Race. Originally all National pianos equipped with the Automatic Whippet Race diorama also had a colorful placard along the bottom of the race track that provided instructions for operating the device. Oftentimes this instruction placard is missing, but what follows is the text from an intact sign: