US1521571A - Automatic musical instrument - Google Patents

Description

Dec. 30. 1924.

T. F. CHEEK AUTOMATI G MUS I CA INSTRUMENT Filed Oct. 6, 192g M r 6 b l w Patented Dec. 30, 1924.

UNITED STATES PATENT OFFICE.

TOLBERT F. CHEEK, OF NEW YORK, N. Y., ASSIGIQ'OR TO =J- 1'lZ|L'lElvCEI'ZwrlilON CORPORA- TION, .OF NEW YORK, N. Y., A CORPORATION OF NEW' YORK.

AUTO1VJIATIG ELCUSICAL INSTRUMENT.

Application filed To all whom it may concern:

Be it known that I, ToLBEnTF. CHEEK, residing at New York city, county of Bronx, and State of New York, a citizen of the United States, have invented certain new and useful Improvements in Automatic Musical Instruments, of which the following is a specification.

This invention relates to musical instruments and particularly to that class of in struments known as reproducing instruments wherein the music of the artist .is automatically reproduced by the instrument -giving the exact expression as was given by the artistwhen he played the selection for the making of the master roll. An example of an expression mechanism for sucha reproducing mechanism is that described in the patent to VVelte and Bockisch, No. 1,008,291.

In instruments of this character, in order to bring out the changes in expression which take place in very short intervals of time, it is necessary to have all of the parts of the mechanism respond to the changes caused by the control perforations in the music sheet. If the parts do not respond quickly, to the control elements, either from inertia or friction, the musical effect is impaired.

It is the primary object of this invention to produce an improved expressban-regulator valve which will have very little in ertia and will have practically no friction, thus enabling it to respond instantly, to any changed conditions brought about by either a change in the setting of the expression mechanism or by variation in the number of notes being played.

Referring to the drawing wherein I have illustrated an embodiment of my invention.

Fig. 1 is an elevational View showing the valve box in cross section.

Fig. 2 is a view from the right of Fig. 1 and showing part of the mechanism in cross section.

Fig. 3 is a detail cross-sectional view on the line 33 of Fig. 2.

Like reference characters refer to similar parts in the difi'erent views of the drawing. The numeral 10 designates the expression-regulator valve box having a partition 11, the partition 11 having a valve port 12. At one end of the valve box 10 is an opening 13 having a suitable resilient bushing 14,

G, 1922. Serial No. 592,334.

o felt, therein. At one side of the port i a bracket 15 having an opening to re- ;eiv the stem 16 of the valve 17. The stem 16 0f the valve 17 asses through the bushing 14 and is attached to a tension member as the chain or cable 18 to be later more fully described.

I have provided the valve stem 16 with a means to always exert a slight pull on the chain, as the spring 19 attached at the inner end thereof. The other end of the spring 19 is attached to the valve box 10 as at 20.

The partition 11 divides the box 10 into two compartments 21 and 22, the compartment 22 being connected to the main exhaust supply by the connect 23. The compartment 21 is connected to the action chest by the inlet 241-. Another opening from the chamber 21 leads to the regulator pueuinatic 26.

On one end of the movable men'iber of the pneumatic 26 is an arm 27 having an adjustable connection 28 to the rod 29 as shown in Fig. 3. The rod 29 passes through openings 30 in the end of the arm 27 and through an opening in the connection 28. A screw 31 is provided in the connection 28 and extends into the end of the connection to impinge upon the rod 29 and hold it in any desired adjusted position. The connection is cylindrical in form and is free to turn in a noise proof bushing 32 as of felt.

The cable or chain 18 is not only fastened at its ends to the stem 16 and the rod 29, but passes over a pulley 33 which is pivotally mounted on the movable member 34 of the expression pneumatic 35. The expression pneumatic 35 is provided on its movable member with a stop member 36. A stop pneumatic 37 is provided with an arresting member 38 in position to enter the path of the stop member 36 when the pneumatic 37 is collapsed. The expression pneumatic 35 is provided with ducts 39, 40, 41 which control the collapse and expansion of the expression pneumatic as described in the above referred to patent. A suitable tension means as the spring 12 tends to keep the regulator pneumatic 26 expanded.

In operation, the air from the pneumatic action enters the chamber 21 and passes the valve 17 and then goes to the main exhaust by way of the connection 23. The main exhaust is, of course, of sufficient strength to lower the pressure substantially in the chamber 21. As the pressure in the chamber 21 lowers, the. pneumatic 26 is collapsed. This relieves the cable or chain 18 and the valve 17, by the combined forces of the air pressure and the tension of the spring 19, is caused to close. As the valve 17 closes, the exhaust is cut off which with the supply of air from the action chest tends to cause the pneumatic 26 to open. This action takes place until with a given set of conditions the valve 17 will come to rest. If now, by the operation of the pneumatics 35 and 37 to produce a difference in expression, the relation of the valve 17 to the position of the pneumatic 2G is changed, on account of the shittingof the position of the roller 23, this has the effect of either making the pressure in the chamber 21 greater or less depending upon whether the roller 23 is raised or lowered. If the roller raises, the pneumatic 26 will. collapse against the force of the spring 42 until the valve 17 does not permit-sufiicient air to pass to further collapse it. In sudden changing from a fortissimo to a pianissimo, for instance, the "friction and inertia of the parts, may determine the quality of the musical reproduction. The less friction and inertia present, the more responsive will all of the parts be which are operated by the air pressure as controlled by the suction. It will he clearly seen that inasmuch as the valve 17 enters the port, that a minimum of inertia is present due to its small size. It is also clear that since the valve does not touch its port unless actually closed, that there is a minimum of friction.

While I have described an embodiment of my invention, I desire to have it understood that I do not limit myself to the exact showing and that modifications and changes may be made without departing itroln the spirit of my invention and within the scope of the appended claims.

Having described my invention, what .1 claim is:

1. In an automatic musical instrument, an air passage, a valve port in the passage, a tapered valve for the port, the valve being movable into and away from the port, a regulator pneumatic, expression mechanism, and connections between the regulator pneumatic, expression mechanism and the valve.

2. In an automatic musical instrument, an air passage, a tapered valve port in the passage, a valve for the port, guiding means to guide the valve toward and away from the port in a direction substantially parallel to the direction of travel of the air passing through the port, a regulator pneumatic, expression mechanism and connections between the regulator pi'icumatic, expression mechanism and valve.

3. In an automatic musical instrument, an air passage, a valve port in the passage, a valve having guide means for limiting its movement to directions toward or away from its port and along the line of air travel and out of contact therewith during movement, a regulator pneumatic, an expression mechanism and connections between the regulator pneumatic, expression mechanism and valve.

4. In an automatic musiial instrument, an air passage, a valve port in the air passage, a tapered valve for the port, a stem for the valve, a spring tending to move thevelve, in one direction, a regulator pneumatic, an expression mechanism, a tension member connected to the valve stem and to the regulator pneumatic and expression mechanism whereby movement of either the regulator pneumatic or expression mechanism will cause movement of the valve in one direction or permit the spring to move the valve in the other direction.

In testimony whereof I afiix my signature.

TOLBERT F. CHEEK.

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