US2504666A - Melody comb - Google Patents

Description

T. R. DUNCAN lApril 18, 1950 MELODY COMB Filed May 24, 194e Patented Apr. 18, 1950 MELODY COMB Theodore R. Duncan, North Hollywood, Calif., as-

signor to Mattel Creations, Inc., Culver City, Calif., a corporation of California Application May 24, 1948. Serial No. 28,767

9 Claims.

Mypresent invention relates to improvements in music box. combs.

In my United States Patent No. 2,498,119, dated January 3, 1950, entitled musical instruments having pluckable teeth, I disclosed a method of tuning the teeth of a comb successively to each note of a melody with. the teeth spaced according to the rhythm of a. melody so that by moving the finger or a simple plucking device across the row of teeth successively lengthwise thereof at a uni form rate of speed, a. melody was produced. That system. eliminated'. complicated selecting andA plucking devices and permited the application of music' box combs to toys at very low cost.

HoweverT since the embodiments shown in this previous application were designed and intended to be constructed from 'plastic material, further research. was undertaken to try to discover a method of manufacturing metal combs employing a, similar, yet improved principle of tuning. My experiments resulted. in: a number of improvements which it is my object now to disclose.

Since the teeth of Swiss combs are cut from solid meta-1 plates, they are rectangular in' cross section, and can therefore vibrate only as reeds, that is to say, only in one plane; By using round piano wires that can vibrate in any direction and anchoring such wires in a metal bar cast around them. and by using a. metal such. as a zine alloy which shrinks tightly aroundv the wires on cook Ihave found' a music comb having' much finer tonal qual-iti to result. rIhe use of a cast metal which shrinks upon cooling isvery important, because its tight-grip on the wires. permits a maximum of their vibrations to be transmitted to a resonator. When this bar is bolted to a simple resonator such as a. strip of soit wood, a tone results that is similar to that of a pianoforte.

One ot the important objects of this invention is to. provide music box combs of. improved tonal qual-ity that can. be manufactured at lower cost and operated by simpler machinery.

A further object is toA provide combsof. improved intonation. In Swiss combs the pitch of any note depends on how much metal is cut away. This involves the probability of considerable error. The cheaperl boxes of this type are quite noticeably out of tune, while the more expensive ones appear to have a iinal hand tuning of many of the notes. To avoid such errors in tuning, round music wires were chosen by me, because they appear to be perfectly uniform in cross section. The pitch of any note can therefore be controlled-A by controlling the-'length of the. wire.

Eioxences. in the lengths o! wires in my music comb are determined by notches or serrations provided in the cast metal bar. As the relativedepth of these notches results from correspond.- ing notches cut in a steel die, and as these can be machined with great precision, the lengths o'f the Wires in the finished comb can be controlled to very iine degree of exactness;v Therefore one of the principal advantages of 4this invention re sides' in thefact that care taken in machining one piece of metal will result in the production of a' multitude o1' low cost combs, each possessing` the most perfect intonation. My improved method of notchin-g also controls shrinkage, resulting in a further advantage.

A still further object resides in providing vi'- brating members each of which has a uniformcross section throughout its length whereby tuning is effected merely by regulating the length of the member. This feature reduces the margin of error to a fraction of that obtaining Where the entire tooth is cut from a solid metal plate in which inevitable variations in both thickness and length tendto multiply errors in tuning. Further, by reducing the determination of length to the most exact measurements that can be machined in a piece of tool steel, a more perfect tuning is achieved by machine methods than could. be accomplished economically by hand methods.

Yet another object is to provide for contouring the tooth-carrying part of the instrument in an improved manner to prevent shrinkage after casting from injuring the teeth cast thereinto.

Other objects, advantages and features of lnvention will hereinafter appear.

Referring to the accompanying drawings which illustrate preferred embodiments of the invention considered as anew article of manufacture,

Fig. l is a plan view of the complete. comb con-v sidered as the article, the view including a stall positioned to indicate the melody produced by successively sounding the teeth of the row shown.

Fig. 2 isa cross section on line 2-2 of Fig. 1-.

3 is an enlarged. fragmental, reproduction of the left hand. portion of the comb shown in Fig. i.

Fig. 4 is a plan view of a modification. includ' img av music staff.

Fig. 5 is a section. on line 5-f5 of Fig'. 4.

Referring in detail to the drawings, the elongated comb body 5' made of a bar of die-east zinc aziloy, the preferred'. ingredients of which will be hereinafter disclosed. As toA its or sideto-sidesaid comb body is of a uniform' dimension from end. to end, excepty for a series of slight, partly circular bosses E concentric about bores 'I extending transversely through the comb and used in securing it to a resonator board. But as to its breadth there is a progressive, intermittent decrease of dimension of the comb body, so that it may be said, in general, to taper from one end to the other.

This taper has been called intermittent" because of the approximately rectangular notches 8, which are located in one edge of the comb body and are spaced apart from each other in a series extending longitudinally of the comb.

A series of resonant, round piano wire teeth are provided consisting of a long end tooth IU, short end tooth -II and (in the illustrated embodimentin Fig. 1) nine intermediate teeth I2.

4 have lengths and diameters so proportioned to each other as to produce the required melody.

In Fig. 4 a series of pluckable, resonant, wire teeth are shown extending along the edge portion of a zinc bar I5 into which they have been cast so as to be rmly gripped thereby, and which have their outer ends at the same level. Along the tooth-carrying edge portion of this'comb extends a series of notches the deepest of which is designated I6, the next deepest Ilia, and the remaining notches IIib, these notches all having iiat bottoms. Also a wide fiat area II is provided between two of said notches IBb and other shorter areas IIa, IIb

' and I'Ic are shown on the same level. On each Said teeth are all gripped tightly within the zinc body 5 extending from edge to edge thereof. The aforesaid notches 8 are shown located midway between adjacent teeth, one reason for this being to aid in equalizing the shrinkage of the cast zinc alloy in relation to the individual teeth I2.

In order to save material and provide for the desired progressive variation in the lengths of the teeth of the comb, said teeth, while being maintained parallel to each other, are all shown somewhat inclined in relation to the long axis of the comb body or bar 5. When the comb is positioned as in Fig. 1, the edge portion of said bar 5 opposite to its tooth-carrying edge is inclined in relation to a plane extending at a right angle to the axis of each of said teeth. In said Fig. 1 is shown a musical staff S wherein is indicated the tone of each tooth by notes on said staff, there also being shown in this view a series IIld of tooth diameter-indications. Along the opposite side of the comb is a series Illy of tooth-length indica-- tions.

In order to control more perfectly the shrinkage of the die cast bar to prevent bending or fracturing of the wire teeth and also to facilitate the withdrawal of said bar from the mold, the straight opposite side portions I3 and I4 of each of said notches are slightly inclined in such a manner as to widen the mouth of each notch. At one side of the midlength of the comb said notch sides I3 are inclined to provide a draft of one per cent whereas the opposite notch sides I 4 of the spa-me notches are inclined to provide a draft of five percent. At the opposite side of the midlength of the comb said notch sides are inclined to the same extent but in the reverse direction in relation to the length of the comb, this being done for the reason that theshrinkage is toward the midlength of the comb.

It will be seen in the modified form shown in Figs. 4 and 5 that the tooth-carrying edge portion of the comb is made up of notches and stepped portions with intervening elevations. This contouring of said edge portion of the comb varies the lengths of the row carried thereby, in such a manner that a melody is produced when the teeth are successively plucked from one to the other end of said row. notches all have side portions inclined or drafted in a manner like that already described in regard to the structure shown in Fig. 1, to control the effect of`shrinkage upon the teeth and to aid in withdrawing the cast article from the mold.

Adjacent the edge of the comb body I5 opposite to its teeth is shown a music staif S' carrying a. tune which, if the teeth of the comb are plucked from left to right will produce a melody'entitled Good Night Ladies." The teeth of the comb The various aforesaid V side of the deep notch I6 a step 16s is shown.

` Teeth designated I8 are rooted on the II, Ila, IIb and I'Ic levels, and hence, all being of the same length and same cross-sectional size sound at the same pitch when plucked. Other teeth Ia rooted at deeper levels will sound at a lower pitch, while the tooth |81), rooted in the notch I6, will sound at the lowest pitch because it is the longest tooth, owing to being rooted in the deepest notch I6.

On certain of the music combs the notches specified are combined with a system of consecutive melodic tuning, the notches being of uneven depth to produce apredetermined length when the wires are cut off straight. Certain of the wires enter at the bottom of the notches, while others enter at the top. Thus they serve a dual purpose, to tune the wires and to control shrinkage.

Around each wire concentric thereto, extends'a iiat area which extends at least one-tenth of an inch concentrically to the axis of the wire. These areas, designated 5a in places on Figs. 1 and 3, are used for the purpose of making measurements, and also to improve the tone of the wires. The pitch is rendered more true if the wires enter the casting in areas extending at right angles to their axes. This is apparent because the wires vibrating length is the same in any plane when the base is at a right angle. This flat area facllitates measurements to determine the length at which the Wire should be cut off to produce a predetermined tone. As well shown in Fig. 2 the die cast metal base 5 is shown with a narrow thickened back portion 5b which extends from end to end of the comb and which is joined to a part 5c of uniform thickness by a beveled strip 5d. The purpose of this increased thickness is for ballast to direct the vibrations to the resonator, to which the comb is to be attached. Whether the invention is embodied in the form hereinbefore first described, or in the form shown in Figs. 4 and 5, the following instructions regarding the method of casting the body portion of the comb and regarding the metallic composition thereof need to be followed in the manufacture thereof.

The following metallic composition has been successively used in the manufacture of the comb:

Some 'solidication shrinkage is essential, as'

the metal must grip the wires rmly when the casting has cooled, and when the above preferred composition is used a desirable amount of shrinkage results. But the shrinkage must be controlled until the casting is ejected from the die, otherwise the shrinkage of the metal will bend the wires. Bending the wires at the base alters the tone and causes the tone to Waver up and down in pitch.

I claim:

1. A melody comb comprising a cast bar and wires in spaced parallel relation having one end of each embedded in one edge of said bar and terminating in a common straight line, said edge being generally oblique to said wires and being formed with stepped surfaces generally perpendicular to said wires, said steps being at predetermined intervals whereby the length of each successive wire is defined to create a musical scale upon sequential plucking of said wires.

2. A melody comb comprising an elongated cast metal bar having a principal axis running lengthwise of said bar and formed with a plurality of steps separated by notches to control shrinkage and a wire having one end embedded in each step, each of said wires being oblique to the principal axis of said bar and perpendicular to the step from which it projects, each of said wires having its other end terminating in a common line, each succeeding step rising above the preceding step a predetermined amount to control the tone of each wire.

3. A melody comb comprising a cast metal bar formed with a plurality of bosses on one surface each said boss having one flat surface, said flat surfaces being in parallel relation and a plurality of wires in spaced parallel relation oblique to the general axis of said bar and having one end of each embedded in and generally perpendicular to each of said bosses, said bosses extending generally oblique to said bar each said wire havin?,f a free end terminating in a common line, the height of each said boss being such to define the length of each wire to thereby control the tone thereof.

4. A melody comb comprising a cast bar, and a plurality of vibratable wires in spaced parallel relation and having an end of each embedded in one edge of said barA and terminating in a common line, said edge of said bar being formed with stepped surfaces generally perpendicular to said Wires whereby the length of said wires is varied to thereby form a musical scale upon plucking the said wires in a predetermined sequence.

5. A melody comb comprising a cast bar and a plurality of vibratable wires in spaced parallel relation having an end of each embedded in said bar and each extending outwardly from one edge of said bar and terminating in a common line, said edge of said bar being formed with stepped surfaces generally perpendicular to said wires whereby the length of said wires is varied to thereby form a musical scale upon plucking the said wires in a predetermined sequence.

6. A melody comb comprising a cast bar and a Number plurality of vibratable wires in spaced parallel relation and having an end of each embedded in said bar and each extending outwardly from one edge of said bar and terminating in a common line, said edge of said bar being formed with stepped surfaces generally perpendicular to said wires whereby the length of said wires is varied to thereby form a musical scale upon plucking the said wires in a predetermined sequence, and also being formed with a notch between contiguous steps to control shrinkage upon casting.

7. A melody comb comprising a cast metal bar formed with a plurality of steps separated by notches to control shrinkage and a vibratable wire having one end embedded in each step, each of said wires being parallel and oblique to the general axis of the bar and perpendicular to the surface of the step from which it projects, each said wire having its other end terminating ln a common straight line, each said step differing in height from the adjacent step a predetermined amount to thereby control the tone of each wire.

8. A melody comb comprising a cast metal bar formed with a plurality of steps having one surface of each in parallel relation and being separated by notches and a vibratable wire having one end embedded in the said parallel surface of each step, each of said wires being parallel and perpendicular to the step from which it projects, each said wire having its other end'terminating in a common straight line, each said step varying in height from the adjacent step a predetermined amount to thereby control the tone of each wire.

9. A melody comb comprising an elongated cast metal bar having a principal axis running lengthwise of said bar and formed with a plurality of steps each of which has one nat surface and being separated by notches to control shrinkage and a vibratable wire having one end embedded in the flat surface of each step, each of said wires being parallel and being oblique to the general axis of the bar and perpendicular to the surface step from which it projects, each said wire having its other end terminating in a common straight line, each said step being above or below the adjacent step a predetermined amount to thereby control the tone of each wire to establish a musical scale upon plucking each said wire in a predetermined order.

THEODORE R. DUNCAN.

REFERENCES CITED VTThe following references are of record in the le of this patent:

UNITED STATES PATENTS Number Name Date 177,412 Matthews May 16, 1876 w' 1,089,699 Gay Mar. 10, 1914 1,269,511 Roberge June 11. 1918 2,478,602 Stein 1 Aug. 9, 1949 FOREIGN PATENTS Country Date 413,171 Great Britain July 12, 1934

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