US2182198A

US2182198A - Boehm system clarinet

Info

Publication number: US2182198A
Application number: US255510A
Authority: US
Inventors: Oscar E Christensen
Original assignee: Individual
Current assignee: Individual
Priority date: 1939-02-09
Filing date: 1939-02-09
Publication date: 1939-12-05
Anticipated expiration: 1956-12-05

Description

1939- o. E. CHRHSTENSEN 2,182398 BOEHM SYSTEM CLARINET Filed Feb. 9, 1939 Patented Dec. 5, 1939 UNITED STATES PATENT OFFICE 4 Claims.

This invention relates t0 improvemencs in clarinets and pertains particularly to the Boehm system clarinet.

In the present conventional Boehm system 1nodel clarinet, the tones Eh (first 1ine of the stafi) ancl Bb (second space above the stafi) when played or produced by the finger position using only the first finger of each band covering its respective tone hole (the thumb hole being ;overed for both tones anti for the Bb, the twelfth 01 regiser key being openecl) show a decidedly unbalanced quality of intonation.

If the tone Bb (played With the above described fingering) is properly tuned, the tone Eb Ls extremely sharp or high and if the tone Eb is properly tuned, then the tone Bb is extremely fiat or 10W. 'Ihe same situation exists between the tones E anal B, c-o a slightly lesser extent, and Ehe tones F anol C are also slightly involved.

The present invention has for its primary 0bject er purpose to provide a novel mechanism whereby there may be obtainecl a balance of the intonation of the tones Eb-E and F and BbB and C on a clarinet of the Boehm type.

Another object of the invention is to provide a mechanism whereby the above described object may be attained, which is of extremely simple design and which is made use of or operated without requiring any alteration in the regular er established fingering of the instrument.

'Ihe invention Will be best understood from a consideration of the following detailed description taken in conneccion with the accompanying drawing forming part of this specification, With the understancling, however, that the invention is not 130 be confined to any strict conformity With the showing of the drawing but may be changed er modified so 1ong as such changes er modifications mark 110 material departure from the salient features of the invention as expressed in the app8ndecl claims.

In the drawing:

Fig. 1 represents ehe upper main section of a clarinet showing the key mechanism embodying t-he present invention together with certain adjacent keys in spread out relation whereby the relative positions of the parts is more readily Seen.

Fig. 2 is a sectional view on the 1ine 2-2 of Fig. 1.

Fig. 3 1's a sectional view on the line 3-3 of Fig. l.

Fig. 4 is a sectional view on the line 44 of Fig. l.

Referring now more particularly so the drawing, the numeral l generally designates the upper main section of a clarine1: of the Boehm type, h-e Wall struoture of which has been illustrated as laid out er flattened for the purpose of more readily illustrating the relative positions of the 5 keys anal tone holes.

The numeral 2 designates the standard register key pad which is actuated by the key 3 pivoced upon the shaft 4, Adjacent the key 3 is ihe usual thumb hole 5 by which the tones F 10 and C are played.

The numerals B, I anal 8 designate respectively the open tone holes of the conventional instrument by Whi0h are played respectively the tones E-B, DA and CG. The tone holes 6 and I normally have associatecl therewith ehe rings 9 and I0, respectively, and the ririg 9 is supported for oscillation upon the shaft H and in the comventional Boehm system instrument, the ring is also supported upon the shaft H t0 be oseillated therevvith, but in the present improved key arrangement, this ring has a separate support which Will be hereinafter described. Ad- J'acent the tone hole l, a covered tone hole is locaaed over which lies the pad I2 which is also carried upon the shaft H and which is closed simultaneously with the closing of the tone hole J by the second finger of the left band.

Paralleling the shaft H is a shaft I3 upon which a1e oscillatably mounted the sleeves I4, E5 and I6. The sleeve I4 carries a pad I7 which overlies the EbBb tone hole. Connected with the sieeve H5 is a pad I8 which covers a tone hole which is particularly described and claimed in my copending application, Ser. N0. 223545 filed August 6, 1938, by Which the FiiCii tones may be played.

In carrying out the present invention, obere is providerl a shaft I9 which is suspended by and passes through the alined posts 29 and paraliels the register key 3, preferably being dispoSed in ehe position shown, that is, between the register key and the shaft 13. Upon the shaft I9 are mounted for indepenclent or joint oscillation the sleeves 2I and 22. The sleeve 2I carries an 45 arm 23 which overlies the register key 3, as shown, so that when this key is depressed, the s1eeve 21 Will be rocked. The extent of rocking rnovement of this sleve is controlled by the movement limiting foot 24 which merely serves 50 as a safety device Which prevents the accidental turning or rocking of the sleeve to an extent whieh might damage ehe spring 25 which is secured a post and is connected with the sleeve in the conventional manner to cause the arm 23 55 to constantly bear upon the register key in order to maintain the pad 2 in olosed position.

The sleeve 22 carries an arm 26 which in turn carries a pad 27 which normally closes a tone hole 28. Ab the opposite end of the sleeve 22, a finger 29 is supported by the sleeve which positions beneath a finger 3 3 upon the adjacent sleeve 2I. Through the medium of these overlapping fingers 29 and 3ll, the spring 25 operates o constantly maintain the pad 2'! in closed position. There is, however, assooiated with the sleeve 22, a spring 3l which is of lighter tension than the spring 25 anal which operates to insure the raising of the pad 2l when the register key is depresseol. When this key is released, the spring 25, naturally, because of its greater strength, overcornes the tension I" spring 3! and forces both sleeves 2E-22 to oscillate in the proper direction to olose the pacls 2 anal 2l.

As previously stated, the ring i?) 1's ordinarily supported ior oscillation an anal Wibll ehe shait H but in the present improved oonstruction, this ring is carried on. the shaft 533 by the sleeve l and is coupled Wii;h the normally raised pad E2, so that when Zhe ring i is depressed, bhe pad 52 will also he depressed to close the underlying tone hole Whioh is particularly illus raed in. Fig 2. The mechanism by whioh the ring il and pa.d l2 are joined together for the simultaneous oloslng of the pad With the depression of the ring or the olosing of the tone hole l is particularly illustratecl in Fig. 2 wherein the ped ET: has shown attaohed thereto the laterally extending bracket 32 whioh exends under the eclge o:f the edjacent ring 2md this ring is provicied with 8, sec screw 33 by which the proper acljusnnent may be made in the conneotion between the ring ancl pad so that they will oper-a1se srnoothly and without nolse.

Integral With the sleeve 55 with which the ring Hi is connected is an arm 3 lwhioh extends laterally to a position heneath and is normally spaoed from the arm Whioh is carried by the sleeve 22. The arm 3% operates to prevent the sleeve 32 oseillating and to prevenl; the pad 271 being raisecl when che tone hole l is c7osed anal the register key is opened. As previously stated, when the register l;ey is opened without the tone hole i being closed, or in other words, without the ring H3 being depressed, then the pad 2l' Will loe raised.

In the use of the instrument with the present improved meohanisrn, when the first o index finger of eaeh band is depresseol or covering its tone hole i'or the piaying Bb (seoond speoe above the steif) the register key 8 is dopressed With the result hat Ehe additional tone hole which is covered oy the pad 27 will be opened er, in other worcls, the paol 2"5 Will be raisecl. 'Ihis will permit the passage of an additional amount of air through the tone hole to bring the Bb 50ll up to the proper pitoh. This explanation is given or made Wih the undersoancling that the lower notes are first to be properly pitched 01 have been properly pitched the instrument, in which case without the addiizion of the tone hole the playing' of -the Bb sone would be too low. By providlng Ehe additional tone hole 28, his is evercome and Bb tone is brought up to the proper pitch.

In playing the keys E and B, the key of E would oe played oy elosing the tone hole With the finger of the left hand, while the register l;ey is in closed position. By opening the register key, the tone B Will be obtaineol and in ehe ordinary instrument wiish the E properly tune, the B tone would. be 01T or would be 10W. With the present improved devioe, when the register key is opened, the tone hole 28 is opened and the tone B will be brought up to proper pitoh because of the additional air outlet provided by opening the hole 25.

In instruments where Ehe F tone is properly tuned, the provision of the a.dclecl tone hole 28 facilitate-s the playing of C alt the proper pitoh because oi the fach that when the register key is opened for playing the tone C, the added tone opening 28 Will be unoovereol anal this will bring the tone C up to the proper pitch Whioh would be ordinariiy tuned slightly low if the F is tuned correotly.

Frorn the foregoing, it Will be readily apparent that Wi;h the n eohanism herein described, the proper pitches rnay oe obtained for those tones which are ordinarily slightly ofi pitoh in a conventional instrument and also that this mechnnis1n the added advantage of enabling the -usician to ootain these tones et the oorreot pitch Withont meking any changes in the conventional fingering of the instrument.

What is olaimed is:

l. In a Boehm system clarinet, means for bringing the tones Bb, B and C (above the steif) to true picch when the instrument is properly inne-d to Eb E 2Llld F (first line and First space of staff) Whioh oc-mprises the addition of a normally olosed aone hole 130 the instrument, ancl means for opening seid. tone hole simultaneously with the opening of the register key only when the Eingering employed for producing the seid tones Bb, B and C, the seid means being used i'0r the tones Eb-Bb when uslng only Ehe EbBb fingering in Which Ehe first' lnger o1 eaoh hand covers its respeetive tone hole.

2. In a Boehno sys'bern clarinet, n1eans for bringing the ones Bb, B and C (above the stafif) to true pitch when the instrument is properly tuned to Eh, E and F (first line and first space o1 staff), whioh eo1nprises the addition of a normaily closecl tone hole to the instrument, means for opening seid tone hole simultaneously With Ehe opening of the register key only when the fingering is employed Tor producing the seid tones Bb B anol C, the seid means being used for the tones Eb-Bb when using only the Eh-B!) fingering in which the first flngor of each band oovers its respective tone hole, and means for prevenhing ehe opening of the seid addeci tone hole when the register key is open for producing all tones other tnen those first mentioned.

3. In a Boehm systern clarinet, the mechanism ior producing at "arme piteh Ehe tones Bb, B sind C (above the suafi) when the instrument is properly -:nnecl to produoe the tones Eb, E and F, which oomprises a twomart shaft in whioh each part is mounted upon the instrument ior independent oscillation, the instrument having a tone hole added thereto adjacent one of seid shaft parts, a pad for seid added hole earried oy the seid one of bhe shafc parts, an operative coupling between the other shaft part and th-e register key, means whereby the two shaft parts Will be oscillated together to lift seid pad and open the added tone hole, when the register key in openecl for produoing any one of the first mentionecl tones, anal seid means being designed to facilitate opening the register k.ey while holding seid pad egainsi; movement for the production of aertain other tones.

4. In a Boehm syste1n clarinet the mechanism for producing at true pitch the tones Bb, B and C when the instrument is properly tuned 130 produce the tones Eh, E and F, which comprises a two-part shaft mounted adjacent the instrument register key, coupling means between said register key and one of the shaft parts by which opening of the register key will effect oscillation 0f the seid shaft part, resilient means normally urging oscillatlon of the said one shaft part in a. manner co c1ose the registe1 key, the instrument having an added tone hole adjacent the other shaft part, s. pad carried by said other part and normally closing said hole, resilient means normally urging oscillation of the said other part in a direction to remove the pad from the added tone hole, connecting means between the shaft parts which is so constructed and. arranged that oscillation 01 ehe first-mentioned part upon opening of the register key Will permit the second-mentioned resilient means to remove the pad from said tone hole, the first resi1ient means being of greater strength than the second and acting through seid connecting means between the shaft parts to hold the pad seated over the tone hole When the register key is closed, anal means for retaining the said pad in closed position on the added tone hole while fingering the instrument in Ehe conventional manner when the register key is open for producing all tones other than those first mentioned.

OSCAR E. CHRISTENSEN.