US3685383A - Switching apparatus for a player piano - Google Patents

Abstract

A switching apparatus for a player piano or other keyboard instrument including an elongated extrusion which supports a tracker bar means positioned between the roll carrier and the take-up roll of the player piano. The tracker bar means has a plurality of spaced apart air passageways formed therein which are adapted to sense the perforations in the sheet material passing thereover. Each of the ports have a conduit means communicating their width and extending therefrom. One embodiment of the invention includes a bellows type element on the nipple which expands to close a switch when the respective air passageway registers with a perforation in the sheet material. Another embodiment of the invention includes a movable capsule at the end of the nipple which moves to close a switch when the respective air passageway registers with a perforation in the sheet material. The switches are electrically connected to a solenoid and activates the same when the switch means is closed by the expansion of the element on the conduit means. The extrusion supports the tracker bar means, circuit board, terminal bar and electrical leads.

Description

United States Patent Cannon et al.

[1 1 3,685,383 1 1 Aug. 22, 1972 [541 SWITCHING APPARATUS FOR A PLAYER PIANO [72] Inventors: Richard L. Cannon; Leonard R. D.

Smith, both of Yankton, S. Dak.

[73] Assignee: Dale Electronics, Inc., Columbus,

Nebr.

[22] Filed: June 13, 1969 [21] Appl. No.: 833,132

Related US. Application Data I [63] Continuation-in-part of Ser. No. 648,311, June 23, 1967, abandoned, which is a continuationin-part of Ser. No. 503,043, Oct. 23, 1965, abandoned.

[52] US. Cl ..84/160 [51] Int. Cl ..Gl0f 5/04 [58] Field of Search ..84/l60,151,146,107

[56] References Cited UNITED STATES PATENTS 702,030 6/1902 Reynolds ..84/151 X 1,073,792 9/1913 Buechner et a1 ..84/160 1,088,884 3/1914 Dorricott ..84/160 X 1,292,321 1/1919 Hope-Jones ..84/160 X 3,117,481 l/l964 Cushing ..84/16OX 3,141,056 7/1964 Kisker ..84/160 X Primary ExaminerRichard B. Wilkinson Assistant Examiner-John F. Gonzales Attorney-Zarley, McKee & Thomte [5 7] ABSTRACT A switching apparatus for a player piano or other keyboard instrument including an elongated extrusion which supports a tracker bar means positioned between the roll carrier and the take-up roll of the player piano. The tracker bar means has a plurality of spaced apart air passageways formed therein which are adapted to sense the perforations in the sheet material passing thereover. Each of the ports have a conduit means communicating their width and extending therefrom. One embodiment of the invention includes a bellows type element on the nipple which expands to close a switch when the respective air passageway registers with a perforation in the sheet material. Another embodiment of the invention includes a movable capsule at the end of the nipple which moves to close a switch when the respective air passageway registers with a perforation in the sheet material. The switches are electrically connected to a solenoid and activates the same when the switch means is closed by the expansion of the element on the conduit means. The extrusion supports the tracker bar means, circuit board, terminal bar and electrical leads.

6 Claims, 7 Drawing Figures PATENTEDmszz 1912 5y wag? 21 SWITCHING APPARATUS FOR A PLAYER PIANO This is a continuation-in-part of application Ser. No. 648,31 1 filed June 23, 1967, now abandoned which is a continuation-in-part of application Ser. No. 503,043 filed Oct. 23, 1965, now abandoned.

This invention relates to a switching and sensing apparatus for a player piano but is easily adaptable to piano, organ and other keyboard instruments.

The conventional player piano utilizes a plurality of individual pouches which are subjected to a vacuum, and when the vacuum is instantaneously relieved by atmospheric pressure admitted through a hole or opening in a punched belt or the like, a key on the piano is mechanically or pneumatically actuated by means responsive to air pressure within the pouch. These devices are extremely complex and are expensive to manufacture. In addition, they are subject to malfunction with prolonged use and are not readily adaptable to both internal and external application to the piano or organ involved.

An improvement in the player piano art was disclosed in the copending application, Ser. No. 503,043 and generally disclosed a sensing method which was primarily sensitive to the volume of air drawn through the sensing hole with the pressure being present only to insure that volume. A further improvement in the art was made and was the subject of the co-pending application, Ser. No. 648,311 which was a continuation-inpart application of Ser. No. 503,043. In the design of application, Ser. No. 648,311, the sensing was almost totally pressure sensitive and was not dependent on volume in any manner. Dust problems were extremely persistent in the prior art and also somewhat reduced the efficiency of the devices described in the two copending applications since the air being drawn into the passageways formed in the tracker bar would cause dust to enter the vacuum compartment which sometimes resulted in malfunctioning of the apparatus.

Therefore it is principal object of this invention to provide a switching apparatus for a player piano.

A further object of this invention is to provide a switching and sensing apparatus for a player piano or other keyboard instrument.

A further object of this invention is to provide a switching apparatus for a player piano wherein an elongated extrusion supports the tracker bar means, circuit board and switch actuating means.

A still further object of this invention is to provide a switching apparatus for a player piano which includes means to reduce dust from entering the apparatus.

A further object of this invention is to provide a switching apparatus for a player piano which includes means to insure that the apparatus will rapidly repeat notes.

A further object of this invention is to provide a switching apparatus for a player piano which permits the music roll to be operated at the top recommended forwarded speed without notes being missed.

A further object of this invention is to provide a switching apparatus for a player piano which is durable in use and economical of manufacture.

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 hereinafter more fully set forth, specially pointed out in the claims, and illustrated in the accompanying drawings in which:

FIG. 1 is a partial perspective view of the apparatus of this invention with portions thereof cut away to more fully illustrate the invention;

FIG. 2 is a sectional view through the switching apparatus of this invention as seen along lines 2 2 of FIG. 1;

FIG. 3 is an elevational view of a capsule element attached to the passageway conduit;

FIG. 4 is a view similar to FIG. 3 except that the capsule element is illustrated in a compressed condition;

FIG. 5 is an elevational view of a modified form of the element mounted on the passageway conduit;

FIG. 6 is a view to similar to FIG. 5 except that the element is illustrated in its alternate position; and

FIG. 7 is a fragmentary top plan view of the circuit board included in this invention.

The numeral 10 generally designates a suitable housing that contains a portion of the operating components of the apparatus of this invention. Housing 10 is only partially illustrated in FIG. 1 and it should be understood that all of the operating components of the device of this invention could be installed within the housing of the conventional piano or organ that is to be played and that the device contemplated in the drawings represents an arrangement whereby the device of this invention can be adapted to a conventional piano. The sensing apparatus of this invention is primarily adapted for use in the player piano environment but could be readily adapted for use with organs or other keyboard instruments.

The numeral 12 generally refers to a roll carrier while the numeral 14 generally refers to a take-up roll. A roll of sheet material 16 is wound on the carrier 12 and passes from the carrier 12 to the roll 14 in conventional fashion. The numeral 18 refers to an elongated extrusion having a vacuum compartment 20 formed therein which is further defined as vacuum compartment portions 22 and 24. An extruded tracker bar 26 is detachably mounted on extrusion 18 so as to close the compartment portion 24 from the atmosphere. Tracker bar 26 is provided with a plurality of air passageways 28 formed therein and extending the length thereof. Each of the air passageways has a conduit or nipple 30 mounted therein which extends into the vacuum compartment 20 as best illustrated in FIG. 2. Conduits 30 extend diagonally away from passageways 28 in alternate rows so as to provide a staggered affect as best illustrated in FIG. 2. Each of the conduits 30 include a lower end portion 32 having an element 34 or 36 mounted thereon. Element 34 is illustrated in FIGS. 5 and 6 and is best described as a hollow bellows element having an open end embracing one end of the conduit 30 and a closed end 40. Element 34 is provided with a bleed opening 42 extending therethrough intermediate its ends at a point below the lower end of the conduit 30. Element 34 is flexible and is movable from the position of FIG. 5 to the position of FIG. 6. Element 34 is normally in a compressed condition (FIG. 5) when a vacuum is present in the compartment 22 and when the sheet material 16 is closing the respective air passageway 28. When a perforation in the sheet material 16 registers with the air passageway 28, air will enter the passageway 28 and pass into the interior of conduit 30 and the interior of element 34 to expand the same to move the element from the position of FIG. to the position of FIG. 6. Element 36 may be substituted for element 34 is desired and is best described as being of capsule configuration. Element 36 includes an interior compartment 44 which slidably received the lower end portion 32 of the conduit 30. As illustrated in FIGS. 3 and 4, the diameter of the compartment 44 is larger than the diameter of the lower end portion 32 of conduit 30 to provide a loose fit therebetween which serves as a bleed. Compartment 44 is provided with three lugs or protrusions 48 extending therefrom at the lower end therefrom which limit the inward movement of the element 36 with respect to the lower end of conduit 30.

The numeral 50 generally indicates a circuit board which is slidably mounted in the grooves 52 and 54 in extrusion 18. As seen in FIG. 7, a plurality of resilient leaf switches 56 are mounted on the circuit board 50 and extend inwardly to the opening 58 in the central portion of the circuit board 50. FIG. 7 illustrates the fact that the row of switches 56 at one side of the circuit board 50 is staggered with respect to the row of switches 57 at the other side of the circuit board. The numerals 60 and 62 refer to sensing elements positioned at opposite ends of the opening 58 and are adapted to be actuated by sensing elements provided at opposite ends of the tracker bar to permit the apparatus to sense various widths of sheet material. The leaf switches 56 are secured to circuit board 50 by epoxy glue or the like which forms a glue line 64 extending thereover. Leaf switches 57 are secured to the circuit board 50 by epoxy glue or the like which forms a glue line 66 extending thereover. Circuit board 50 is provided with openings 68 and 70 at opposite ends thereof which are adapted to receive screws or the like to aid in the attachment of the circuit board 50 to the extrusion 18 if desired and to facilitate the suspension of the terminal bar 72 below the circuit board 50 as viewed in FIG. 2. The leaf switches 56 are connected to a suitable electrical unit 74 by a lead 76 while leaf switches 57 are each connected to a suitable electrical unit by a lead 78. The leads 76 and 78 extend through the vacuum compartment 22 to the electrical unit 74 which in this case would be a solenoid operated striker positioned adjacent the piano string to cause the striker to strike the string and sound the proper note when the leaf spring 56 associated therewith is moved into electrical contact with the terminal bar 72 by the element 34 on conduit 30. Terminal bar 72 is a common terminal bar for all of the leaf switches and is connected to a source of power 80 by a lead 82. The source of power 80 is connected to the electrical unit 74 by a lead 84. The numeral 86 generally designates a cut out area in the extrusion 18 which serves as a wire or lead conduit. Assuming that the element 36 is the particular element positioned on the conduit 30, the normal method of operation is as follows. The rolls l2 and 14 are powered by any conventional reversible motor (not shown) and the motor is adapted to pass the sheet material 16 over the tracker bar 26 so that the perforations 88 will register with the outer ends of the air passageways 28 at times. Switch 90 is closed simultaneously as power is provided to at least one of the rolls 12 or 14 to cause the sheet material 16 to commence its movement over the tracker bar 26. A conventional blower or vacuum pump (not shown) will create a partial vacuum in the compartment 20 of extrusion 18 and the elements 36 would normally be in the position illustrated in FIG. 4 until such time at the respective air passageway 28 communicates with a port 88. The resiliency of the leaf switches 56 and 57 is such that they normally urge the element 36 to the position illustrated in FIG. 4. When a perforation in the sheet material registers with an air passageway 28 in the tracker bar 26, atmospheric pressure is allowed to rush in through the tracker bar, through the conduit 30 and into the interior of element 36. The atmospheric pressure in the element 36 causes the element 36 to move the leaf switch into in engagement with the terminal bar 72 thereby completing a circuit to the proper solenoid assembly located in the proper sequence over the piano key, under the piano wipen or action thereby sounding the correct note at the correct time and for the correct amount of time. The return of the element 36 from the position of FIG. 3 to the position of FIG. 4 is accomplished by the amount of resiliency incorporated in the leaf switch and such return will be accomplished as soon as the perforation in the sheet material moves out of register with the air passageway 28. The small area between the outer wall of the conduit 30 and compartment 44 may be termed a bleed area and its purpose is to allow the vacuum pressure to draw the sheet material tightly against the tracker bar thereby minimizing leakage between one air passageway and an adjacent air passageway in the tracker bar. Shoulder 48 in element 36 restricts the element 36 from being pushed tightly over the end of the conduit 30 which could seal the flow of air therethrough in either direction. Additionally, the reduced diameter portion 46 below the shoulder 48 serves as an of accumulation to hold any dust or debris that would be drawn into the system. The dust or debris that is collected in the area 46 may be vacuumed from the apparatus by simply passing a vacuum cleaner or the like over the tracker bar and does not require any disassembly of the apparatus. The fact that the dust is captured in the area 46 renders the dust harmless to the rest of the system and prevents the dust from reaching the switching area.

The element 34 functions in a manner substantially identical to the element 36 and would expand from the position of FIG. 5 to the position of FIG. 6 when the air passageway 28 registers with a perforation in the sheet material. The expansion of the element 36 causes the leaf switch 56 to be moved into engagement with the common terminal bar 72 thereby activating the proper solenoid assembly. The bleed opening 42 serves to permit the vacuum pressure in compartment 20 to to draw the sheet material tightly against the tracker bar thereby minimizing leakage between one air passageway and an adjacent air passageway in the tracker bar. The interior of the element 34 also serves as an area of accumulation for dust or debris as did the area 46 in element 36.

The ability of the apparatus to repeat notes rapidly is accomplished by the resiliency in the leaf switches and the smooth surfaces incorporated on both of the elements 34 and 36. The sensitivity of this system is such that the music roll or sheet material may be run at the top recommended forward speed without the unit faltering, missing or cutting out notes as often happens with other pneumatic systems.

The extrusion 18 has several purposes, namely, it holds the circuit board, it forms a vacuum chamber, it holds a tracker bar and it holds the entire player mechanism together thereby forming a rigid solid fixture. Thus it can be seen that a unique switching mechanism has been described for use in the player piano environment with permits the player piano to properly and accurately play the notes as indicated by the perforations in the sheet material. It can also be appreciated that means has been provided herein for preventing dust or debris from reaching the switching mechanism of the apparatus which eliminates malfunctioning problems. The elements 34 and 36 insures that the piano will be properly operated without any notes being cut, missed or misread. Thus it can be seen that the device accomplishes at least all of its stated objectives.

Some changes may be made in the construction and arrangement of our switching apparatus for a player piano without departing from the real spirit and purpose of our invention, and it is out intention to cover by our claims, any modified forms of structure or use of mechanical equivalents which may be reasonably included within their scope.

We claim:

1. in a device of the class described,

a support means having a closed compartment formed therein and a tracker bar means at one side thereof,

a vacuum source connected to said compartment for creating a vacuum therein,

a plurality of air passageways in said tracker bar means extending therethrough and in communication with the outside atmosphere, a hollow conduit means connected at one end of each of said passageways and extending into said vacuum compartment, a hollow member connected to the other end of each of said conduit means and movable from first to second positions,

a plurality of switches in said compartment adjacent said hollow members and being responsive to force applied thereto by said hollow members, each of said switches being normally open when the hollow member positioned adjacent thereto is in its first position and being closed when said hollow member moves to its second position,

said switches being connected to a source of electrical power,

a sheet having a plurality of perforations,

said sheet being in movable contact with said tracker bar means so that at least some of the perforations thereof will come into register with at least some of said air passageways to admit air into said air passageways, conduit means and hollow members,

a plurality of electrical units selectively electrically connected to certain of said switches so that at least one electrical unit will be actuated when air is permitted to pass into one of said passageways, and

each of said hollow members comprising a capsule element slidably mounted on said conduit means, said capsule element including an interior compartment w ich slidably receives sai conduit means, 83.! lntCX'lOl' compartment avrng a shoulder portion therein to limit the movement of said capsule element in one direction with respect to said conduit means whereby the entrance of air into one said hollow members causes said one hollow member to move to its second position to close the switch means associated therewith.

2. The device of claim 1 wherein said capsule element loosely embraces said conduit means to provide a bleed area between said conduit means and the interior compartment of said capsule element.

3. The device of claim 1 wherein each of said switch means is comprised of a resilient leaf spring element normally engaging and yieldably urging said hollow element to said first position.

4. The device of claim 1 wherein said support means is formed from an elongated extrusion adapted to receive said tracker bar means at one side thereof, said extrusion having a circuit board means slidably mounted therein and received thereby, said switches being on said circuit board.

5. The device of claim 4 wherein said extrusion has a cut-out area formed in a side opposite to said one side adapted to receive a plurality of leads extending therethrough, said leads connecting said switch means to said electrical elements.

6. The device of claim 1 wherein said air passageways are aligned in a single row across said tracker bar means, said conduit means being alternately staggered so as to extend over said switch means in a staggered manner.

Claims (6)

1. In a device of the class described, a support means having a closed compartment formed therein and a tracker bar means at one side thereof, a vacuum source connected to said compartment for creating a vacuum therein, a plurality of air passageways in said tracker bar means extending therethrough and in communication with the outside atmosphere, a hollow conduit means connected at one end of each of said passageways and extending into said vacuum compartment, a hollow member connected to the other end of each of said conduit means and movable from first to second positions, a plurality of switches in said compartment adjacent said hollow members and being responsive to force applied thereto by said hollow members, each of said switches being normally open when the hollow member positioned adjacent thereto is in its first position and being closed when said hollow member moves to its second position, said switches being connected to a source of electrical power, a sheet having a plurality of perforations, said sheet being in movable contact with said tracker bar means so that at least some of the perforations thereof will come into register with at least some of said air passageways to admit air into said air passageways, conduit means and hollow members, a plurality of electrical units selectively electrically connected to certain of said switches so that at least one electrical unit will be actuated when air is permitted to pass into one of said passageways, and each of said hollow members comprising a capsule element slidably mounted on said conduit means, said capsule element including an interior compartment which slidably receives said conduit means, said interior compartment having a shoulder portion therein to limit the movement of said capsule element in one direction with respect to said conduit means whereby the entrance of air into one said hollow members causes said one hollow member to move to its second position to close the switch means associated therewith.

2. The device of claim 1 wherein said capsule element loosely embraces said conduit means to provide a bleed area between said conduit means and the interior compartment of said capsule element.

3. The device of claim 1 wherein each of said switch means is comprised of a resilient leaf spring element normally engaging and yieldably urging said hollow element to said first position.

4. The device of claim 1 wherein said support means is formed from an elongated extrusion adapted to receive said tracker bar means at one side thereof, said extrusion having a circuit board means slidably mounted therein and received thereby, said switches being on said circuit board.

5. The device of claim 4 wherein said extrusion has a cut-out area formed in a side opposite to said one side adapted to receive a plurality of leads extending therethrough, said leads connecting said switch means to said electrical elements.

6. The device of claim 1 wherein said air passageways are aligned in a single row across said tracker bar means, said conduit means being alternately staggered so as to extend over said switch means in a staggered manner.

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