US3003384A - Organ with motor-driven blower - Google Patents

Description

Oct. l0, 1961 GINZO KIKUGAWA` ORGAN WITH MOTOR-DRIVEN BLOWER Filed March 16, 1959 Arr;

soossa t Y tonGAN wngrMororuvrsN-BLOWER t `Glnluxkugawa, ohshl, en, oV BllhkoDenklKaKalshmTokymJapan met Mu. 16, 1959, ser. 10,199,652

z cum. (c1. stt- 355) This invention relates te s feedrpgnpmvided with `a silent motor-driven blowersupplying thenecessary pres-` sure air for musical playing thereof, thus dispensing with` foot-pedals for generating thecompressed air.

The main object of Lthe invention isto provide animproved 'organfof the ykind abovereferred to, wherein the n unfavourableblcwer minimized to an allowable degree, so that the musical sounds r may be pleasantivrenioyed;

Another object of the invention is to provide a furtherj improved organ ofthe kind above mentioned, wherein` the required power for driving the blower is reduced to a;

In order to full the above describedobjects, the in- ,r 1

vention resides in an organ with motor-,driven blower,

' comprising: a number of vibrating tongu or reeds arranged in a row; a-iirst air chamber in communication with the atmospherethrough an inlet opening; a second air chamber arranged just below said first air chamber, said first and second air chambers being adapted to com `murlicate with eachotherthrough a number of normally closed air passage openings, when at least one of the latter is opened, each of said tongues `being fixed to a wall of said rst chamber and extending into the corresponding one of said passage openings; a spring-loaded and. normally closed-lid for each ofthe latter; keyboard means to operateeach lid when the corresponding musical key is depressed; an upper air space in communication with said second air chamber; a lower air space in communication with said upper air space; a silentmotor-blower assembly resiliently mounted within said second yair spaceby a plurality of supporting arms with cushioning means and comprising a multi-stage blower and an electric Y nummer pins sto` unter keys.; are manges in s horizontal'frow on the bar 4. Keys 3`are resiliently urged to` occupy their normal position by afsamev number of 7, again in a horizontal on astationary supportingmember 6 fixed to, casing 1, thefsaid memberbeingananged in the`neigh-' borhood of the cover-supporting-upper end of said casing.v Underneath the rowof Akeys 3, there isfarrauged a first air chamberr 8, which vsxed on Va second air cham- 9. The first chamber 8'is provided with an inlet opening'` having ,l a substantial klength and passing throughs side kwallof the chamber. lllfdeno'tes an adjustable cover adapted `tondjust the air quantity introduced into the rst air'chamber l8, the upper end of the n cover being hinged yat the upper portion of the same side wall, as provided withsaid opening 8', of the `lrst air chamber 8, while the lower end of said cover is kept at an: adiustable height as vtlesired yby a suitable operating indicated at 10' byr dotted lines to adjust the clearance between` the upper wall 9a of second air chamber 9-andthe lower end of said cover. A definite number of( openingslz corresponding to the number of keys 3 are provided in the upper wall 9a of second air chamber 9 andarrangedin a-horizontal row. kA same number of vibratingftongues 13-as` keys 3 are arranged in a horizontal row, one end of each ton-gue is fixed on to the upper surface of wall 9o bya bolt`f14, while the opposite end of said tongue is kept free, a substantial part of each tongue except the root portion thereof overlying the corresponding air passage ork opening l2, which is normally i closed by a movable cover or lid 15. These covers 1S are arranged in a horizontal row underneath the upper .wall

of rsecond air chambery 9, each of said covers is provided recessedfslots 1'6 and 17 at the opposite ends thereof,

respectively, ,the said slots. being slidably engaged by pins 16' and 17',y respectively. These pins project from the motor'direct-coupled tothe latter; a dished shell covering xed as shown. A connecting vrod 19 slidably Vpasses said blower asa whole in a separated relation therefromdescription given below, takenin connection with the` accompanying drawings illustrating by way of example a preferred embodiment of this invention.

In the drawings: f

FIGURE l shows a cross-section of the organ according to this invention;` n

FIGURE 2 represents a longitudinal section of part` thereof, taken on the line I--I in FIG. 1.

t Now, referring to the drawings, a preferred embodit through which the connecting rod 19 slidably passes. The

. side walls of outer casing l. An inner casing 23is ar-" ranged within the outer casing 1, the upper wall of the Y lower surface .ofy upper wall of second air chamber 9 and arranged in ytwo horizontal rows. Each cover 15 isurged toclose theA mating opening 12 by a leafspring 18', one end of which is 4kept in contactwith the lower surface of said cover '15, while the opposite end of the spring is through the first air chamber 8 and mechanically connects the centre portion of key 3 with 4the end portion of the lcorresponding movable cover 15. Sealing rings 20 and 21 made of felt are provided at the wall openings air chamber assembly r8,r 9 is ixedly mounted on a 'couple of rigid supporting shelves 22, 22', which are arranged oppositely to each other and rigidlyfiixed to the former being lfixed to the-lower surfaces of said shelvcs'ZZ andk 2.7.',` A connecting pipe connects the inner spacej of said inner casing 23 rwithnthat of thesecondair chamj ber `il and one or more openings 25 are provided at the ment of this invention will be describedmore in detail. kInthe drawings, l1 denotes theouter casing of the orl gan according to this inventionythe `said casing is opened at the bottom, and providedffwith a vcover 2, which` is pivoted at one side of the top of said casing. VThere are provided a number of keys 3 arranged in a horizontal plane, each of which is pivoted at its root portion by a i pin 5 to ahorizontal supporting bar 4 xed to casing 1 soas to rockin a horizontal plane within certain limits.

`It'wll be clear from the foregoing that a corresponding bottom wall of said casing 23. A separating wall 26 is provided horizontally at a suitable height within the inner space of said inner casing 23, thus separating theyl said space into two, more specifically into upper and lower air chambers U and L, which communicate, however, with eachother by an opening 27 provided at saidsepa-I rating wall. A motor-driven fan-assembly F, whichwill -1 be described hereinbelow more indetail, is' housed inthe lower air chamber;` The motor 28-comprises av rotor z shaft -f 29 ,provided'with upper and lower shouldersa.

29b; arotor 31 mounted on the said nrotor shaft; testator" core 32; a stator winding 33 vmounted thereon; amotor *f f housing 34 mounting said stator core 32; upper and lower end covers 35 and 35'; upper and lower bearing covers 36 and-31; upperand lower bearings 38 and fasin the Y lvavtentedoct. 10 1961,

yusual manner. From the periphery of said upper end cover 3S, a plurality of supporting arms 40, 41 extend, each of the latter is fixed through the intermediary of a resilient cushioning rnembe r 46 or 47 on a seatv 42 or 43 projecting `from the inside wall surface of said inner casing 23, by means of a`bolt 44 or 45,' respectively. 4.8 and` 49 denotejlower and upper Ablower stages of the blower, the bosses 5,0 and 51 of the both stages are mounted 4on the rotor shaft,k Z9 'with a close iit and; in a stack bear against the shoulder 3 0 on said' shaft 29while.

the upper surface of said upper boss "511is` pressed upon by a nut` 52, which is tightly screwed on the upper screwed endof rotor shaft 29, thus the blower assembly 48, 49 being rigidly, but` dismountably fixed on the last mentioned shaft. Blower blades 48'., 49" or blowers 48, 49 are so constructed and arranged, that they compress air in operation, blowing it 4from inside to outside thereof. A dished shell S3. covers the blower assembly 48, 49 from above and is mounted iixedly on supporting arms 40, 41. The upper end wall of dished shell 53 is provided at its centre with an opening 54 positioned oppositely to said opening 27 provided in, separating wall 26, the remaining end wall portion of said shell 53 being posi.- tioned in opposite relation to the blades 49 of the upper blower 49 with a small gap therebetween. Asealing means 55 shaped in a ring is inserted between both openings 27 and 54 in sealing engagement with wall 26 and shell 53. A stationary guide ring 56` is arranged between blower stages 48 and 49 and fixed at its outer peripheral bent edge to the inner wall surface of shell 53- by means of a plurality of bolts 57, the said ring 56 being provided with a number of guide vanes 56', which serves to guide air from vthe first blower stage to the second through central opening 58 in ring 56 and from outward to inward. In the upper and lower air chambers in the inside casing, there are a plurality of baille plates 59, 60, 61 and 62, projecting in a vertically staggered manner from the inner wall surface of said casing 23. Thus, in operation, the air sucked by the blower assembly, as well as the same delivered from the latter, flows in a zigzag-shaped path, which serves to reduce the blower noises to a minimum. On the inside of the shell 53, noise-absorbing material 63 such as felt or the like is iitted, and in the similar manner the same material 64 is attached to the back surface of guide ring 56.

In operation, the motor 23 is energized and rotates the blower assembly 48, 49, thus air being induced from the upper air chamber within casing 23 through openings 27 and 54 to the upper blower stage 49 and driven by the varies 49 from inside to outside. Then the air is guided through stationary guide vanes 56 from outside to inside and ledv to the lower blower stage 48. Thence, the air is driven by the blower blades downwards, guided by a plurality of baiiies 61, 62, and finally discharged from the lower air chamber through opening 25 to the atmosphere, thereby the air pressure within the upper air space and the second air chamber 9 being kept reduced to that lower than the atmospheric. When the music player presses down any one of the keys 3, the-corresponding lid or cover 15 is also depressed downwards by the connecting rod 19 against the action of spring 18, thus the corresponding opening -12 is opened, so that atmospheric air is induced through one or more openings 8 cut through the side wall of the first air chamber 8, and thence to the second air chamber 9, thereby the corresponding tongue 13 vibrates under the inuence of the air iiow passing round the latter and develops thus the desired musical sound as long as the key 3 under consideration is kept depressed by the player.

In such an organ,- as above referred to, air iiow for the playing music is developed by the motor-blower assembly. If appreciable blower noises should issue they would produce disturbing eiects upon the musical sounds. Thus, it is.. imperative to minimize the blower ynoise as muchv as,v possible.. 'Iliis kindof noise, increases with increase of peripheral speed of the blower. 0n the other hand, the pressure in the second air chamber 9 and, thus the upper air space within inner frame Z3, should be kept at a proper value lower than the atmospheric by a suitable diierence, in order to vibrate one or more tongues 13 wheny the corresponding key or keys are operated. In the present enbodimentofthis invention, the blower is divided into. two upper and lower stages, betweenwhich a guide ring is arranged as hereinbefore described for the purpose of operating the said two blower stages in series, and, thus to fulfil the labove mentioned two necessary conditions. For a particular rotational speedand pressure drop, the radiusof the two stage blower will be reduced to half, as compared with a mono-stage blower conventionally employed; With the blower radius reduced to the half, the noise level will be also reduced to the hal-f, which inturn substantially suppresses the audible noises, because the human sense of hearing responds logarithmicaliyto theintensity of sound vibrations. With use of blower or blowers of reduced diameter, the revolutions will be correspondingly reduced lfor a definite ai-r delivery, soL that the effect as set forth hereinabove ina-ybe advantageously, attained. If the number of the blower stages is increased to 3- or more, the desired effects will be further increased. In this way, blower noises normally encountered with use of an organprovided with a motor-driven blower can be substantially minimized' to such a degree, that they are scarcely =fe1t by ther human acoustic sense, thus the musical sounds played with the organ are kept undisturbed. Furthermore, by= employing a twoor more stageblower, the power consumption can be more or lless reduced in comparison. with an organ using a mono-stage-blower, which Voperates naturally with higher peripheral speed of the blower' blades, because Ithe higher the tip speed the higher will be the mechanical loss of the blower. By employing.L a multi-stage blower, the width of the organ. is also. appreciably decreased.

In this invention, lfurthermore, the configuration of the dished shell covering the blower assembly from above is such that it guides and directs a part of the air driven by the upper stage of the blower, which is directed Aout.- wardly and would be otherwise ineffective, to iiowr downwards as an effective air stream, thus enabling theblower eiiiciency tobe improved to still greater extent. On the other hand, the already mentioned provision ofl a sound absorbing material attached to the inner surface of the dished shell contributes naturally further todecrease the blower noises. The same material provided on Ithe back of guide ring 56 contributes to obtain the same effect.

In view of the fac-t that the invention provides a vhighly improved organ with motor-driven blower, it -Will be understood that the foregoing description is to be considered not as limitative but merely illustrative, and` that modifications of the invention are possible and' are included within its scope as defined `by the appended claims.

What I claim is:

l. A reed organ, comprising: an outer casing; a key-p board comprising a plurality of keys disposed in said` casing for playing the organ; a plurality of walls defining first and second chambers in the casi-ng, one of" `the casing supporting said walls; `an inner .casing Rpl ported suspended vfrom said shelves in the VQuientiaeingfbers and providing an air passage therebetween; a horizontal wall dividing the :inner casing into upper and lower chambers communicating with each other through an opening in the horizontal wall; ay motor-blower assembly carried by arms mounted on resilient members supported at interior sides of the inner casing in the lower chamber; a dished shell in the lower chamber covering said vblower and spaced therefrom to direct air downwardly, said shell |being supported on said arms; spaced vanes defining multiple stages of said blower rotatable in the shell; a stationary vane guide ring disposed between the rotatable vanes and secured to the interior of the shell, said shell having an upper central opening providing an air passage between the interior of the shell and said upper chamber through vthe opening in saidhorizontal wall; spaced baille plates in the upper chamber defining a -rst tortuous air path and further spaced baille plates in the lower chamber spaced -from said motor and delning second tortuous air path, said inner casing opening to the atmosphere at the end of said second air path, whereby air drawn under suction through the outer casing is substantially free from noises produced by the motor-blower `assembly when leaving the opening in the inner casing.

2. A reed organ according'to claim l. wherein said shell and said guide ringr are lined with sound absorbing material."

References cina in the me of this pam:A UNlTED srATEs PATENTS 363,531 Metcalf 1 May 24, 1887 1,320,224 Garman Oct. 28, 1919v 1,431,907 Cramer Oct. 10, 1922 2,234,490 Gilbert Mar. 1-1, 1941 FOREIGN PATENTS 229,868 Great Britain Mar. 5, 1925 532,379 Great Britain Jan. 23, 1941

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