US3444770A

US3444770A - Player piano tracking and transpose system

Info

Publication number: US3444770A
Application number: US584884A
Authority: US
Inventors: Richard L Cannon; Charles M Morse
Original assignee: Dale Electronics Inc
Current assignee: Dale Electronics Inc
Priority date: 1966-10-06
Filing date: 1966-10-06
Publication date: 1969-05-20
Anticipated expiration: 1986-05-20

Description

R. L. CANNON ET AL PLAYER PIANO TRACKING AND TRANSPOSE SYSTEM Filed Oct. 6, 1966 542 any '/8 /A/ vzwras p/CHAPO A. CAM/01v 671 42155 M. M04255 United States Patent 3,444,770 PLAYER PIANO TRACKING AND TRANSPOSE SYSTEM Richard L. Cannon and Charles M. Morse, Yankton,

S. Dak., assignors to Dale Electronics, Inc., Columbus,

Nebr., a corporation of Nebraska Filed Oct. 6, 1966, Ser. No. 584,884 Int. Cl. G01f /06 US. Cl. 84-139 11 Claims ABSTRACT OF THE DISCLOSURE A tracking and transposing system for a player piano including a single pole, double throw tracking switch connected by an electrical circuit to a reversible drive DC. motor which re-aligns the sheet material by laterally adjusting the roll carrier. The DC. motor can also be locked in position to prevent lateral movement of the roll carrier during the rewind cycle.

This invention relates to a tracking system and in particular to a tracking and transposing system for player pianos.

The piano rolls commonly used on player pianos have an irregular width and thus the music rolls have a tendency not to roll in alignment even when the carrier and take-up rolls are axially aligned. Moisture in the atmosphere also will cause the paper to expand thereby providing irregularities in the width of the music roll. Another problem is that the spools sometimes are not in complete alignment.

Another problem sometimes presented by a player piano is that it may be out of tune a half step and thus lateral movement of the music roll will bring the piano back intune. Moreover, it is sometimes desired to play the piano in a different key and this may be accomplished by adjusting the music roll laterally on the carrier rolls and take-up rolls as required.

Thus, one of the principal objects of this invention is to provide a tracking system for player pianos that will continuously adjust the music roll to compensate for any irregularities in width or lateral movements of the roll as it is being operated.

Another object of this invention is to provide a tracking system for player pianos which may be used to transpose the music roll for the piano to play in the desired key.

Yet another object of this invention is to provide a tracking system for player pianos which will accommodate rolls of varying widths and includes a tracking sensing means adapted to engage only one side of the music roll.

Yet another object of this invention is to provide a tracking and transpose system for player pianos having a carrier or wind-up roll which is adapted to be laterally moved as the piano is being played but will remain completely stationary during the rewinding of the carrier roll.

A related object of this invention is to provide a tracking system for player pianos wherein an adjusting means is provided for controlling the lateral movement of the carrier roll, said lateral adjusting means including a reversible drive motor which is stopped during the rewinding of the carrier roll by the application of balanced DC. current to the coils of the reversible drive motor.

A still further related object of this invention is to provide a tracking system for player pianos wherein an A.C. electrical supply source is connected through a rectifier to the coils of a reversible drive motor when the carrier roll is being rewound to thereby eliminate any lateral movement of the carrier roll as it is being rewound.

A further object of this invention is to provide a player piano tracking and transpose system which is simple in 3,444,770 Patented May 20, 1969 design, economical to manufacture and defined in appearance.

These and other objects will be apparent to those skilled in the art.

This invention consists in the construction, arrangements, and combination of the various parts of the device, whereby the objects contemplated are attained as hereafter more fully set forth, specifically pointed out the claims, and illustrated in the accompanying drawings in which:

FIG. 1 is a fragmentary top plan view of the tracking and transpose system mounted on a player piano;

FIG. 2 is a fragmentary end elevation view taken along line 2-2 in FIG. 1;

FIG. 3 is a cross-sectional view taken along line 33 in FIG. 1; and

FIG. 4 is an electrical schematic for the tracking and transpose system.

As illustrated in the drawings, the tracking and transpose system of this invention is employed on a player piano. The player piano includes a roll carrier or rewind roll 10 havingmusic roll sheet material 12 wound therearound and connected to a take-up roll 14. As seen in FIG. 1, the music roll extends over a tracker bar 16 positioned between the roll carrier 10 and the take-up roll 14.

A support frame 18 is provided and slidably receives a longitudinal shaft 20 extending from the roll carrier 10. A cam wheel 22 is mounted on the shaft 20 and is limited against relative longitudinal movement on the shaft by weldments 24. A coil spring 26 is positioned on the shaft 20 between a shaft bearing 28 and the cam wheel 22 to yieldingly urge the roll carrier to the right as viewed in FIG. 1. A rewind motor 30 is provided with a shaft 32 telescopically engaging the outer end of the shaft 20. The shaft 32 includes a longitudinally extending slot 34 in which a transversely extending pin 36 carried by the shaft 20 is positioned. The length of the slot 34 sets the limits of latter movement of the roll carrier 10.

A tracking motor 38 is provided adjacent the cam wheel 22 and includes a drive shaft 40 having a cam arm 42 rotatable in a plane parallel to the longitudinal axis of the shaft 20 and perpendicular to the plane of the cam wheel 22. A cam roller 44 is positioned on the outer end of the cam arm 42 for engagement with the outer face of the cam wheel 22. The spring 26 yieldingly causes the cam wheel 22 to engage the cam roller 44.

A limit switch 48 having an actuating lever 50 is provided on the opposite side of the cam wheel 22 in the path of the cam arm 42 for engagement with the cam arm upon extreme rotation of the cam arm 42 in a counterclockwise direction as viewed in FIG. 2.

A tracking switch 52 is mounted on the frame 18 and is provided with a sensing element 54 extending through an opening 56 in the tracker bar 16. The tracking switch 52 is a single poledouble throw switch as seen in the schematic of FIG. 2. When the music roll 12 is in engagement with the sensing element 54 the switch is in the solid line position (FIG. 4) and when the music roll 12 has moved out of engagement with the sensing element 54 the sensing element is in the dash line position. The tracking switch 52 is adjustably mounted on a threaded shaft 57 extending through the frame 18 to thereby position the sensing element 54 as desired adjacent the longitudinal edge of the music roll 12.

In FIG 4, it is seen that a forward and rewind switch 60 is provided for being actuated upon the roll 12 being completely played. Electrical lead wires 62 are provided for being connected to an electrical A.C. power source. One of the lead wires is connected to a lead wire 64 which in turn is connected to the center of the coils in the reversible drive motor 38. The outer ends of the coils are connected by

lead wires

66 and 68 through the normally closed limit switch 48 and the tracking switch 52 to the other lead wire 62 when the forward and reverse switch 60 is in its solid line position of \FIG. 4. A second circuit is provided for connecting the lead wire 62 to the reversible drive motor 38. This circuit includes a rectifier 72 and is operable when the forward and reverse switch 60 is moved to its dash line position as indicated at 74. The power to the reversible drive motor coils is converted to DC. power by the rectifier 72. A resistor 75 connected in series with a capacitor 76 is connected across the

coil lead wires

66 and 68. The reversible drive motor 38 is locked by the balanced DC. power supply applied to each of the coils in the motor.

'In operation it is seen that as the music roll 12 is fed across the tracker bar 16 the roll carrier shaft 20 is being normally urged to the right as viewed in FIG. 1 and at the same time the cam arm 42 is being rotated in a counter-clock-wise direction as viewed in FIG. 2 until the edge of the music roll 12 engages the sensing element 54 of the tracking switch 52. At this time the direction of the tracking motor 38 is reversed through operation of the tracking switch 52 and the came arm 42 begins rotating in a clockwise direction to cause the roll carrier to move to the left asviewed in FIG. 1 thereby eventually moving the music roll 12 out of engagement with the sensing element 54. At this time the cam arm 42 again is reversed in its direction of movement by the operation of the tracking switch 52 and the spring 22 then moves the roll carier 10 to the right again. Thus it is seen that the roll carrier 10 is continuously being moved back and forth along its longitudinal axis as indicated by the pair of arrows 80 in FIG. 1.

As the music paper 12 crowds the switch sensing element 54 to the right, the switch energizes the motor to move the cam and

roller

42 and 44 respectively, which in turn moves the music roll 12 to the left away from the switch sensing element 54. As the roll is moved to the left, the switch changes its circuit to energize the motor 38 to move the cam roller to the right (FIG. 2). Therefore, the carrier roll is constantly changing direction and the moving is very slight if the music paper is tracking properly. In any event the necessary amount of lateral movement of the carrier roll is provided to cause the music paper to track properly.

If older torn music roll is used, the tracking system will correct itself if the edge is not too eratic. However, if the roll is too badly torn, the system will correct itself by movement of the cam to the right until it engages the limit switch 48 and remains there until the torn portion has passed. When the smooth edge is again available, the tracking will continue to function properly. At the end of the play cycle, the system is put into a locked condition by the single pole, single throw switch 60 which is activated by a relay not shown. After the roll is rewound and the relay shuts off the system, the cycle starts over when the roll is repeated or replaced by another.

It is seen that by appropriate adjustment of the tracking switch 52 in FIG. 3 the tracking motor 38 will automatically move the music roll to the right or left one hole or musically one-half step thereby raising or lowering the key one-half step.

Thus it is seen that there are no shut-off or neutral positions in the tracking system. It is constantly correcting the tracking of the music roll. In the rewind cycle, the tracking motor through the use of a rectifier locks itself and cannot be forced in either direction. Therefore, the spring tension used to hold the music roll in place and the vibration of the rewind motor will not cause it to creep in either direction and thereby preventing any misalignment which would tend to bunch up and fray the edge of the music roll paper. It is apparent that the life of the music roll paper can be extended substantially. This locking feature eliminates a common problem with player pianos wherein the paper tends to creep in the rewind cycle and eventually destroys the edge of the music roll.

Some changes may be made in the construction and arrangement of our player piano tracking and transpose system without deparating from the real spirit and purpose of our invention.

We claim:

1. A tracking system for player pianos, comprising,

a roll carrier,

sheet matrial wound on said roll carrier,

a sheet material take-up means for receiving said sheet material from said roll carrier,

power means for moving said sheet material from said roll carrier to said take-up means,

a tracking sensing means positioned adjacent the side edge of said sheet material between said roll carrier and said take-up means, and

tracking adjusting means operatively connected to said sensing means to control the lateral movement of said sheet material moving between said roll carrier and said take-up means,

power means for rewinding said roll carrier, and holding means for holding said roll carrier stationary against lateral movement during the rewinding thereof,

said tracking adjusting means including a reversible drive motor operatively connected to said roll carrier to provide lateral movement in response to actuation of said sensing means and said holding means includes an electrical circuit providing balanced DC. current to said motor for locking said motor against rotation and thereby holding said roll carrier against lateral movement.

2. The structure of claim 1 wherein an A.C. power source is connected to the coils of said reversible drive motor and a rectifier is provided in said circuit between said A.C. source and said coils.

3. The structure of claim 2 wherein a telescoping sha-ft unit having telescoping members extends between said roll carrier and said power means for rewinding said roll carrier, a cam wheel is fixedly mounted on one of said telescoping members, a cam arm is connected to said reversible drive motor for rotational movement in a plane parallel to the longitudinal axis of said telescoping unit and perpendicularly to the plane of said cam wheel, said cam arm engaging said cam wheel for moving said roll carrier back and forth as the direction of rotation of said reversible motor is reversed.

4. The structure of claim 3 and spring means normally yieldingly biases said cam wheel against said cam arm.

5. The structure of claim 4 wherein one of said telescoping members has an elongated longitudinal slot and the other telescoping member has a transversely extending pin received in said slot to limit the extent of relative telescopical movement.

6. The structure of claim 5 and a limit switch is positioned in the path of said cam arm such that upon rotation of said cam arm away from said cam wheel a predetermined distance said limit switch is actuated.

7. A tracking system for player pianos, comprising,

a roll carrier,

sheet material wound on said roll carrier,

power means for moving said sheet material lfl'OIIl said roll carrier to said take-up means,

said tracking adjusting means includes a reversible drive motor operatively connected to said roll carrier to provide lateral movement of said roll carrier in response to actuation of said sensing means.

8. The structure of claim 7 and a spring means yieldingly urges said roll carrier longitudinally against said adjusting means and upon said sensing means being actuate said adjusting means moves said roll carrier longitudinally in the opposite direction against the action of said spring.

9. The structure of claim 8 wherein said adjusting means includes a support tfor said roll carrier and a longitudinal center shaft extending from said roll carrier, a cam wheel mounted on said shaft and limited against relative longitudinal movement, and :a cam arm connected to said reversible drive motor for engagement with said cam wheel, said arm being rotable in a plane parallel to the longitudinal axis of said shaft and perpendicular to the plane of said cam wheel.

10. The structure of claim 9 wherein said sensing means is connected to a single pole, double throw tracking switch and said switch is included in an electrical circuit with said reversible drive motor, said sensing means actuating said switch to one position when engaging said sheet material and actuating said switch to said other position when out of engagement with said sheet material, and a power source connected to said circuit to continuously operate said reversible drive motor for said cam arm to move either towards or away from said cam wheel thereby continuously providing longitudin'al adjustment :for said roll carrier.

11. A tracking system for player pianos, comprising,

a roll carrier,

sheet material wound on said roll carrier,

said sensing means being connected to a single pole, double throw tracking switch and said switch being included in an electrical circuit with a reversible drive motor, said reversible drive motor beoing connected by said adjusting means to said roll carrier, said sensing means actuating said tracking switch to one position when engaging said sheet material and actuating said switch to said other position when out of engagement with said sheet material, and a power source being connected to said circuit to continuously operate said reversible drive motor 'for said tracking adjusting means to move said roll carrier back and forth thereby continuously providing lateral adjustment for said sheet material.

References Cited UNITED STATES PATENTS 1,360,565 11/1920 J. OConnor 84-137 RICHARD B. WILKSON, Primary Examiner.

J. F. GONZALES, Assistant Examiner.