US3722351A

US3722351A - Musical instrument keyboard construction

Info

Publication number: US3722351A
Application number: US00094288A
Authority: US
Inventors: A Nordquist; I Allen; E George
Original assignee: Pratt Read Corp
Current assignee: Pratt Read Corp
Priority date: 1970-12-02
Filing date: 1970-12-02
Publication date: 1973-03-27
Anticipated expiration: 1990-03-27

Abstract

A musical instrument keyboard includes a wood key bed and a pivot-spacer member for receiving a plurality of keys. The pivotspacer member has upwardly extending spacer posts for confining the key sticks in a supported position so that transverse forces on the keys, tending to cause a torque to be exerted thereon, will not affect the normal position of the keys. The forward end of each key stick cooperates with side tabs of the associated key cap to form a channel for a guide bushing supported on the key bed, which limits lateral and up and down movement of the keys.

Description

United States Patent [191 Allen et al. Mar. 27, 1973 [5 MUSICAL INSTRUMENT KEYBOARD 2,764,907 10/1956 Link 84/434 CONSTRUCTION 3,110,21l 11/ 1963 Elbrecht 3,447,414 6 1969 LoDu ..8 6 Inventorsl Irving Allen, Westbrook; Edward T 3,417,649 12i196s ..84/433 George, Hamden; Albert W. Nordquist, Ivoryton, an of Coml- Pn'mary ExaminerRichard B. Wilkinson Assistant Examiner-John F. Gonzales 73 As e.Prtt-RdC rah I 1 s lgne 2 ea orpo voryton Att0meyMueller and Alchele [22] Filed: Dec. 2, 1970 [57] ABSTRACT [21] Appl. No.: 94,288 A musical instrument keyboard includes a wood key bed and a pivot-spacer member for receiving a plurali- [52] U S Cl 84/423 84/434 ty of keys. The pivot-spacer member has upwardly ex- [511 In} .0 Gioc 3/12 tending Spacer posts for confining the y sticks in a 58] Fie'ld 433436 supported position so that transverse forces on the 84/430 keys, tending to cause a torque to be exerted thereon, will not affect the normal position of the keys. The forward end of each key stick cooperates with side [56] References Cited tabs of the associated key cap to form a channel for a guide bushing supported on the key bed, which limits UNITED STATES PATENTS 3 lateral and up and down movement of the keys.

,175,451 3/1965 Klann ..84/433 3,254,554 6/1966 Nordquist ..84/434 12 Claims, 6 Drawing Figures PATENTEU MR 2 7 I975 SHEET 1 BF 2 FIGE Ill

BY W 54% ATTORNEYS.

PATENTEDHARZYIQYS 2, 51

sum 2 0F 2 INVENTORS IRVING ALLEN EDWARD T. GEORGE ALBERT W. NORDQUIST ATTORNEYS.

MUSICAL INSTRUMENT KEYBOARD CONSTRUCTION BACKGROUND OF THE INVENTION This invention relates generally to musical instrument keyboards.

Musical instrument keyboards include a plurality of keys in parallel side-by-side arrangement which are pivotal about a point between their ends whenthe key is depressed and released. The point of pivoted movement of each key generally is in longitudinal alignment with each other key along the keyboard frame and means are provided for holding the keys in a fixed position with respect to the keyboard frame while permitting the keys freely to pivot when depressed and released. Such means may include metal pins, or the like, driven into the rear portion of a wooden key bed and the pins are arranged to extend upwardly through slots or holes formed in the bottom of the keys. Some type of bushing, such as felt cloth, is then used in the slot between the key and the metal pin to provide quiet operation of the key while also limiting forward and rearward movement of the key and to provide the proper touch quality to the musician playing the musical instrument having such a keyboard.

Such prior art constructions have certain disadvantages. For example, the metal balance pins used must be machined to a proper size, which adds to the cost of manufacture, and then these pins must be driven into a wooden key bed which, at times, splits or cracks necessitating repair or scrapping of the key bed. Moreover, as mentioned above, a bushing is required in addition to the balance pin further increasing the cost and complexity of such keyboard constructions.

While the disadvantages of the above-described keyboard are manifestly concerned with cost and complexity of manufacture, this type of keyboard has acquired substantial acceptance by musicians because of the touch quality ofthe keyboard. Therefore, when designing keyboards for reducing manufacturing costs, many times the changes made affect the touch" quality substantially so that the resultant keyboard is unacceptable.

Another problem with musical instrument keyboards of the prior art is that under certain playing conditions the keys may tend to rotate about their longitudinal axes because of the key pivot and support arrangements heretofore used. This is particularly true when playing upon the keyboard in a glissando fashion, i.e. dragging the fingers over the keysfrom bass to treble, or vice versa.

SUMMARYOF THE INVENTION I Accordingly, it is an object of this invention to provide improved musical instrument keyboard assemblies which have substantially the same touch qualities as prior art assemblies, but which have substantially fewer components and are less costly to manufacture and easier to assemble.

Another object of this invention is to provide improved musical instrument keyboard assemblies whereby transverse forces on the keys do not cause torsional movement of the keys during playing of the musical instrument as, for example, when playing in glissando fashion, i.e. dragging the fingers over the keys from bass to treble, or vice versa.

A further object of the invention is to provide a musical instrument keyboard including keys formed by a wood stick and a plastic cover piece, wherein the wood stick and the plastic cover piece cooperate to provide a channel cooperating with a guide secured to the key bed to limit the lateral and updown movement of the keys.

Briefly, the keyboard construction of this invention includes a hardwood frame structure or key bed including hardwood forward and rearward rails spaced apart in fixed relation to one another by a plurality of wooden slats. Secured to the forward rail is a comb-like member formed of a metal stamping, which has upwardly extending, rearwardly turned finger guide members. Positioned on each of the guide members is a resilient guide. Each of the keys, i.e. the natural and sharp keys, are formed of a key stick, preferably of wood, upon which is positioned a key cap, a white cap for natural keys and a black raised cap for the sharp keys. However, it will be understood that the color of the, keys may vary as desired. The caps have downwardly turned sidewall portions which cooperate with the key sticks to form a channel which confines the resilient guides therein. The downwardly turned sidewall portions of'the key caps may extend only a short longitudinal distance, just sufficient to form the guide channel or they may extend the entire longitudinal length of the key.

A pivot-spacer member, preferably of molded plastic, forming an integral unit of, for example, a length to receive one octave of keys, is secured to the rear rail of the hardwood key frame. In the illustrated embodiment, the rear rail of the key frame has an elongated slot formed therein and the pivot-spacer member has a downward portion which fits into the slot and can be there held in place by adhesives, or the like. The spacers consist of upwardly extended portions which are positioned on each side of a key stick closely em bracing the same, and the upward extent is at least onehalf the vertical height of the key stick to prevent even slight rotation thereof.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a top view partial segment of a keyboard constructed in accordance with this invention;

FIG. 2 is a side elevational, partially sectional view of the keyboard of FIG. 1;

FIG. 3 is a side sectional view through a natural key cap used with this invention;

FIG. 4 is a side sectional view through a sharp key cap used with this invention;

FIG. 5 is a partial perspective view with portions broken away illustrating the relationship of the hardwood keyboard frame components; and

FIG. 6 is an enlarged fragmentary view showing a portion of the pivot-spacer member for receiving and holding a key stick in accordance with this invention.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now to FIGS. 1 and 2, there is seen a key receiving frame or key bed, designated generally by reference numeral 10, including forward and rearward portions over which is positioned a plurality of pianolike keys. A metal stamped guide 12, which has a comb-like configuration, is secured to the key receiving frame by screws 13, it being understood that such fastening can be accomplished by any other suitable means. A pivot-spacer member 14 is secured to the key receiving frame at the rearward portion thereof for securely receiving and holding a plurality of key members, such key members being both natural keys l6 and sharp keys 18.

Referring now additionally to FIG. 5, the key receiving frame 10 is of hardwood construction including a plurality of pieced together hardwood components securely fastened either by glue, wood screws or staples or any combination thereof. In the instant case the components are held together by glue and staples. In the illustrated embodiment the key receiving frame 10 includes a forward rail member and a rearward rail member 22 which are held together by a plurality of hardwood slats 24 extending therebetween and the slats also serve as spacers between the

rails

20 and 22. The forward rail 20 has a plurality of milled slots 20a aligned with corresponding milled slots 22a formed in the rear rail 22, and hardwood slats 24 are firmly secured within these aligned slots. The hardwood components provide for a strong, lightweight support frame or key bed which absorbs much of the undesired noise that may be generated by the manipulation of the

keys

16 and 18.

The front key guide 12 is best shown in FIG. 5. It may be formed as a metal stamping having a solid strip portion 26 from which extend a plurality of longitudinally aligned spaced apart guide fingers 28 which have their upper-most portions bent over rearwardly to face the rear rail 22. Although the guide fingers 28 appear to be at equally spaced apart locations, in fact they are not as the spacing between different ones thereof may vary slightly. An undercut 28a is formed at the bent over top end portions, and laterally extended projections are provided at the termination of the guide fingers. Positioned on each of the bent over portions is a resilient guidemember 30 which is held firmly in place on the undercut portion 28a by the laterally extended projections 28b. Only one of such resilient guides 30 is illustrated in FIG. 5, but it will be apparent that such a resilient guide is provided on each guide finger. The notches or undercuts 28a in the fingers 28 are designed to coact within the opening through the resilient guides 30 to retain the resilient guide in a fixed position thereon without the use of cement. Therefore the width of the extended portions of the resilient guides can be increased without being rotated during manipulation of the key.

The pivot-spacer 14 is best illustrated in FIGS. 2 and 5, and is preferably made of molded plastic material so as to be of unitary construction. However, the pivotspacer may be a metal stamping or fabrication as desired. A rib 32 forms the main support portion of the pivot-spacer 14 and has the bottom portion thereof inserted into a milled groove 34 within the rear rail 22. The rib 32, at spaced apart locations thereon, forms pivot points at the upper edge thereof to receive the piano-

like keys

16 and 18, so that the keys rotate about these pivot points when manipulated. A plurality of longitudinally spaced apart, vertically extended spacers 36 are formed on the rib 32 and extend upwardly a distance at least greater than half the height of the key sticks 16a and 18a to firmly confine the stick member and prevent relative rotation of the keys. The spacers 36 have a width or dimension in the direction of the keys which is greater than that of the rib 32 which forms the pivot points. Each of the spacers 36 is tapered upwardly, front and back, in the order of 2, and tapered upwardly at its sides in the order of onequarter degree, to facilitate parting of the unit from its mold when such part is molded plastic.

Each of the keys l6 and 18 have associated therewith a key stick, preferably of laminated wood construction. FIG. 2 illustrates the key stick 18a and a sectional view of its associated sharp key 18. Here it can be seen that the key stick 18a, like all other key sticks, has a milled groove 40 at its front end which forms upper and lower extended portions 40a and 40b, respectively. The key is positioned with respect to the front guide 12 so that the

portions

400 and 40b extend above and below the resilient guide member 30 of the guide 12. The upper and lower portions 40a and 40b limit the extent of vertical travel of the key to that point at which they engage the resilient guide member 30. The key stick 18a, as do all other key sticks, may have an actuating wire 42 secured at the rear end thereof which is used in any one of several conventional manners to actuate a switch mechanism to sound a musical note. Other actuating devices may be used in place of the wire 42. For example, metal or plastic clips may be used in place of the wire, or the switch itself may have an actuating member which bears directly on the wood key. Also, a felt pad 43 may be positioned on the front rail just beneath the forward end of the natural keys 16. This pad prevents the natural keys 16 from making noise when depressed and prevents the natural keys 16 from pivoting about the stop 30 which could otherwise act as a fulcrum.

The sharp keys 18, as seen in FIGS. 2 and 4, are of molded plastic construction, having a crown portion 44 which is positioned well above the natural keys 16, in the usual manner. A support tab 46 extends downwardly from the inner wall of the crown 44 and engages the wood stick 180. This tab serves as a spacer to hold the crown at the proper elevation above the natural keys 16. At the rear of the sharp keys 18 is formed a gripping portion 48 which, together with the sides of the key, engage the key stick 18a, firmly to be held in position thereon. The sharp keys may be glued in place, or otherwise secured, as desired. Downwardly extended side wall tabs 50 are formed on each of the sharp keys 18 to be positioned on each side of the milled groove 40 so as to form a channel therewith confining the guide member 30. That is, the tabs 50 may engage slightly with the sides of the guide member 30 during up and down manipulation of the keys, and this arrangement prevents lateral movement of the keys.

Referring now to FIG. 3, a sectional view of a natural key 16 is shown. The key 16 includes a downwardly turned front end 52 to form the front exposed portion of the keys. As previously stated, the front end 52 engages the felt pad 43 when the key 16 is depressed. Downwardly turned side wall portions 54 engage opposite sides of an associated key stick 16a, and the key may be glued in position, if desired. The plastic key 16, when used in an electronic organ application, is of sufficient rigidity that the extended end thereof beyond its associated key stick 16a is self-supporting. However, if

the keyboard arrangement is used in a piano, stiffening ribs may be provided under the cap to ensure the proper rigidity. The end segment 56, at the rear of the natural key 16, and the end segment 48, at the rear of the sharp key 18, are provided to be inserted under a fascia board, not shown, which forms part of the musical instrument. In like manner, the key 16 is provided with downwardly extended sidewall tabs 58 which are in substantially the same position with respect to the frame as are the sidewall tabs 50 of the sharp keys 18. This provides uniform alignment of the channels formed by the

tabs

50 and 58 and the associated notch 40 in the key sticks so that they engage the longitudinally aligned finger portions 28 and their associated guide members 30.

Referring now to FIG. 6, there is shown an enlarged fragmentary view of the pivot-spacer 14, with the rib 32 thereof extending upwardly from the rear rail 22. The rib 32 has a rounded upper end 60, preferably semi-circular, engaging a tapered groove 62 formed in the underside of the key stick 18a, it being understood that each key stick 18a and 16a includes a similar tapered slot. The tapered slot 62 is sufficiently wide at the bottom to allow free movement of the key stick about the crown portion 60, without the key stick binding against or interfering with the rib 32 to limit the free pivotal action of the key. The tapered slots 62 are provided sufficiently deep to substantially reduce the amount of torque about the longitudinal axes of the keys. That is, the distance d between the pivot point and the top of the natural key, and the distance d between the pivot point and the top of the sharp key is made small to reduce the rotary torque that is exerted on the key when manipulated during playing.

What has been described is a simple and inexpensive keyboard construction which is readily manufactured with a minimum of components and which, being made of substantially wood construction, is less susceptible to noises produced by manipulation of the keys.

We claim:

1. A musical instrument keyboard assembly includ-' ing in combination:

a key receiving frame for receiving a plurality of musical instrument natural and sharp key means; guide means formed along a forward portion of said key receiving frame;

pivot-spacer means secured to said key receiving frame at a rearward portion thereof, said pivotspacer means having discrete pivot portions extending upwardly therefrom and longitudinally aligned, and further having a plurality of stationary spacer portions extending upwardly with confining surfaces on opposite sides of said discrete pivot portions; and

a plurality of discrete elongated key means positioned on said key receiving frame to form an instrument keyboard, each key means being positioned between adjacent ones of said plurality of spacer portions and having a pair of side surfaces cooperating with said confining surfaces of said spacer portions on opposite sides thereof to hold such key means against rotation, each key means having a transverse notch rearwardly thereof to receive an appropriate one of said discrete pivot portions for pivotal movement thereon and a forward portion engaging said guide means for proper alignment,

said spacer portions having a dimension in the direction of said elongated key means which is greater than that of said pivot portions.

2. A musical instrument keyboard assembly in accordance with claim 1 wherein the portion of each of said key means adjacent said plurality of spacer portions of said pivot-spacer means has a rectangular cross-section, and said spacer portions have an upward extent greater than one-half the height of said key means.

3. The musical instrumentkeyboard assembly of claim 1 wherein said discrete pivot portions and said plurality of spacer portions are formed as a single molded unit.

4. The musical instrument keyboard assembly of claim 1 wherein said key receiving frame has a longitudinal slot formed in the rear portion thereof, and wherein said discrete pivot portions and said plurality of spacer portions are formed as a single molded unit having a downwardly extending portion fitting into said longitudinal slot and an upwardly extending portion forming said discrete pivot portions.

5. The musical instrument keyboard assembly of claim 1 including channel means formed near the forward end of each key means to engage said guide means to limit the upward and downward movement of i said key means during manipulation thereof.

6. The musical instrument keyboard assembly of claim 5 wherein said guide means includes longitu dinally spaced apart portions, said key means includes natural keys and sharp keys, and said channel means of both said natural keys and said sharp keys are in longitudinal alignment along said key frame to engage respective ones of said longitudinally spaced apart portions of said guide means.

7. The musical instrument keyboard assembly of claim 5 wherein each of said plurality of elongated key means is formed of an elongated key stick, and a key cap having integral top and downwardly extending portions firmly to receive the forward endof its associated key stick, said key stick and said downwardly extending portions being shaped to form said channel means to receive a respective one of said guide means.

8. The musical instrument keyboard assembly of claim 7 wherein said forward end of each of said key sticks has a cut-out portion and saiddownwardly extended portions of corresponding ones .of said key caps have further extended portions adjacent said cut-out portion of said key stick to cooperate therewith to form said channel means and confine the respective associated ones of said guide means within said channel.

9. In a musical instrument keyboard assembly, the

combination including:

a key frame having forward and rearward portions for receiving a plurality of piano-like natural and sharp keys, said natural keys terminating near the forward portion of said key frame and said sharp keys terminating at an intermediate location between said forward and rearward portions;

pivot means extending upwardly from said key frame at said rearward portion and longitudinally aligned therealong to receive said plurality of piano-like natural and sharp keys;

guide means including a plurality of upwardly extending and rearwardly turned guide fingers positioned at said intermediate location;

a key stick for each of said plurality of piano-like natural and sharp keys, each key stick having means engagable with said pivot means and a cutout at the forward end of said key stick to receive a corresponding one of said guide fingers; and

a key cap positioned over each of said key sticks and having a portion cooperable with said cut-out therein to form a channel to confine said guide finger.

10. The musical instrument keyboard assembly of claim 9 wherein said key cap includes downwardly extending portions on each side thereof to cooperate with said cut-out on the associated one of said key sticks to confine the associated one of said guide fingers.

11. The musical instrument keyboard assembly of claim 10 wherein at least one of said downwardly extending portions forms a sidewall of said key cap.

12. A musical instrument keyboard assembly, including in combination:

a hardwood frame structure including hardwood forward and rearward rails spaced apart and a plurality of wooden slats secured to said rails and holding the same in fixed relation to one another;

a comb-like guide member secured to the forward rail and having rearwardly turned finger portions in longitudinal alignment one with the other and extending along the forward rail at spaced apart locations;

a resilient guide member positioned on each of said finger portions;

a pivot-spacer member of integral molded plastic construction secured to the rearward rail and having spaced portions forming a plurality of discrete pivot portions in longitudinal alignment one with the other and along the rearward rail, and a plurality of spacer portions extending upwardly on opposite sides of said discrete pivot'portions;

a plurality of key sticks, one for each of a plurality of natural keys and one for each of a plurality of sharp keys, each key stick having means engag able with said discrete pivot portions and confined between a corresponding pair of said spacer portions, and a cut-out formed at the forward end of each of said key sticks for receiving a corresponding one of said resilient guide members on said finger portions, said spacer portion having an upward extent which is greater than one-half the height of the key sticks positioned therebetween; and v a key cap positioned over each of said key sticks and having downwardly extending portions cooperable with said cut-out to confine said resilient guide member, thereby guiding said key stick and its associated key cap during manipulation thereof.

Claims

1. A musical instrument keyboard assembly including in combination: a key receiving frame for receiving a plurality of musical instrument natural and sharp key means; guide means formed along a forward portion of said key receiving frame; pivot-spacer means secured to said key receiving frame at a rearward portion thereof, said pivot-spacer means having discrete pivot portions extending upwardly therefrom and longitudinally aligned, and further having a plurality of stationary spacer portions extending upwardly with confining surfaces on opposite sides of said discrete pivot portions; and a plurality of discrete elongated key means positioned on said key receiving frame to form an instrument keyboard, each key means being positioned between adjacent ones of said plurality of spacer portions and having a pair of side surfaces cooperating with said confining surfaces of said spacer portions on opposite sides thereof to hold such key means against rotation, each key means having a transverse notch rearwardly thereof to receive an appropriate one of said discrete pivot portions for pivotal movement thereon and a forward portion engaging said guide means for proper alignment, said spacer portions having a dimension in the direction of said elongated key means which is greater than that of said pivot portions.

3. The musical instrument keyboard assembly of claim 1 wherein said discrete pivot portions and said plurality of spacer portions are formed as a single molded unit.

5. The musical instrument keyboard assembly of claim 1 including channel means formed near the forward end of each key means to engage said guide means to limit the upward and downward movement of said key means during manipulation thereof.

6. The musical instrument keyboard assembly of claim 5 wherein said guide means includes longitudinally spaced apart portions, said key means includes natural keys and sharp keys, and said channel means of both said natural keys and said sharp keys are in longitudinal alignment along said key frame to engage respective ones of said longitudinally spaced apart portions of said guide means.

7. The musical instrument keyboard assembly of claim 5 wherein each of said plurality of elongated key means is formed of an elongated key stick, and a key cap having integral top and downwardly extending portions firmly to receive the forward end of its associated key stick, said key stick and said downwardly extending portions being shaped to form said channel means to receive a respective one of said guide means.

8. The musical instrument keyboard assembly of claim 7 wherein said forward end of each of said key sticks has a cut-out portion and said downwardly extended portiOns of corresponding ones of said key caps have further extended portions adjacent said cut-out portion of said key stick to cooperate therewith to form said channel means and confine the respective associated ones of said guide means within said channel.

9. In a musical instrument keyboard assembly, the combination including: a key frame having forward and rearward portions for receiving a plurality of piano-like natural and sharp keys, said natural keys terminating near the forward portion of said key frame and said sharp keys terminating at an intermediate location between said forward and rearward portions; pivot means extending upwardly from said key frame at said rearward portion and longitudinally aligned therealong to receive said plurality of piano-like natural and sharp keys; guide means including a plurality of upwardly extending and rearwardly turned guide fingers positioned at said intermediate location; a key stick for each of said plurality of piano-like natural and sharp keys, each key stick having means engagable with said pivot means and a cut-out at the forward end of said key stick to receive a corresponding one of said guide fingers; and a key cap positioned over each of said key sticks and having a portion cooperable with said cut-out therein to form a channel to confine said guide finger.

12. A musical instrument keyboard assembly, including in combination: a hardwood frame structure including hardwood forward and rearward rails spaced apart and a plurality of wooden slats secured to said rails and holding the same in fixed relation to one another; a comb-like guide member secured to the forward rail and having rearwardly turned finger portions in longitudinal alignment one with the other and extending along the forward rail at spaced apart locations; a resilient guide member positioned on each of said finger portions; a pivot-spacer member of integral molded plastic construction secured to the rearward rail and having spaced portions forming a plurality of discrete pivot portions in longitudinal alignment one with the other and along the rearward rail, and a plurality of spacer portions extending upwardly on opposite sides of said discrete pivot portions; a plurality of key sticks, one for each of a plurality of natural keys and one for each of a plurality of sharp keys, each key stick having means engagable with said discrete pivot portions and confined between a corresponding pair of said spacer portions, and a cut-out formed at the forward end of each of said key sticks for receiving a corresponding one of said resilient guide members on said finger portions, said spacer portion having an upward extent which is greater than one-half the height of the key sticks positioned therebetween; and a key cap positioned over each of said key sticks and having downwardly extending portions cooperable with said cut-out to confine said resilient guide member, thereby guiding said key stick and its associated key cap during manipulation thereof.