US1228222A - Electric switching mechanism. - Google Patents

Description

F. B. LITTLE.

ELECTRIC SWITCHING MECHANISM.

APPLICATlON FILED MAR. I3, |916. 1,228,222. Patented May 29,1917.

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F. B. LITTLE.

ELECTRIC SWITCHING NIE-CHAN|SNL APPLICATION FILED MAR. 13. |916. N 1,228,222. Patented May 29,191..

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' STATES PATENT OFFICE.

l FREDERICK B. LITTLE, F CHICAGO, ILLINOIS, ASSIGNOR, BY MESNE ASSIGNMENTS, TO Jg C. DEAGAN'MUSICAL IBELLS, 0F CHICAGO, ILLINOIS, A CORPORATION 0F ILLINOIS.

' '15 sound produei-n devices that have electromagnets forl e ecting their operation and Ahas for its object the provision of improved Switching mechanism that is operable by l the keys and Iwhereby injuredA switches may readily be removed and replaced without dismounting the keys. The'importance ofl 4 vmy invention will be appreciated-when it is `understood that' switches frequently break down during amusical performance, hither- Kto requiring mulch time in repair whereas by the4 device of my invention -an injuredvv Switch\may be instantly re laced. In the preferred embodiment'of-the invention I provide a mounting strip at the 'rear of the keyboard, this mountin strip carrying a plurality of, pairs of seria ly re-4 lated contacts, there being one pair of 4such contacts individual to each sound producing device. Each pair of contacts has a pair of .serially related complemcntal contacts, the

a pairs of complemental contacts being mountt ed upon separate carriers. TheJ contacts of elac'hpair has separable engagement with'the contacts of the pair complemental thereto', a

l 4Qplugand jack formation of the interengaging .contacts being preferably.. employed whereby the pair of complemental contacts mounted upon separate carriers may readily7 be engaged with the contactscarried by the mounting strip. Each key has a pair of separable ncontacts individual thereto and carries a switch operator for bringing such contacts electrically together, this switch /operator being desirably in the nature of al ,50 stiff leaf spring operating upon one contact Specivcation of Letters Tatent.

,thimble constituting a jack), a split pin\9 ELECTRIC SWITCHING MEHANIsM.

Patented May 29, 1917.

- u Application 111e@ March 13,1916. Serial No. 88,774.

to force it against its companion, the rst contact being desirably in the 'form' of a leaf spring which will automatically separate from its companion when the corresponding key is released. I will explain my invention more fully by reference to the accompanying drawings showing thepreferred embodiment thereof and in which Figure 1 diagrammatically illustrates 'the preferred embodiment of the 60 invention; Fig. 2 is a plan view of a part of a bank vof keys and associated switching mechanism; and Fig. 3 is a sectional view 0n line 3-3 of Fig. 2. t

Like parts are indicated by similar characters of reference throughout the different figures. The soundproducing devices illustrated in Fig. 1 include each an operating magnet 1 adapted for inclusion in bridge between70 the sides 2 and3 of a supply circuit furnished with current by a battery 4 also in bridge between these sides. Each magnet containing bridge may be traced from the side 2 of the supply circuit through the con- 75 tact 5, the contact 6 normally engaging con- .tact 5, the winding of the magnet, the contact screw 7, the contact thimble 8 into which the screw is threaded (this contact constituting a plug for-reception within the jack 8, theleaf spring 10, al contact l1 complemental to the spring 10 and fromrwhich the spring 10 is normally separated due toI the resilience ofsuch spring, a' screw 12, a 85 contact thimble 13 into which the screw 12 is threaded (this contact im-bleconstituting a jack), a split pin '14 onstituting a plug forreception within the jack 13, to the other side 3 of the supply circuit. Thel conductors 9.0

x which lead from the magnets V1 to the screws 7 kare included in a cable 15 lthat is disposedbeneath'a mounting strip, this mounting strip being separably secured to the back of the keyboard cabinet by screws 17. The contacts 8 and 14l are mounted upon the mounting strip 16, the contacts 14 being in common connection -as they are desirably mounted vupon a conductingstrip 18. The contacts 8, however, are electrical yseparate, 10Q

being individual to the 'magnetsv 1 and the sound producing bars 19-individual to such cal continuations 10 and 11:.of the contactsr 9 and 13 are,- of course, bodily movable with 20 carried by the v1n the contacts 9 and 13 as '.tley are mounted upon the same carrier. T. ese elements 10 a-nd 11 themselves constitute a switch, such switches projecting, at their forward ends, over the rear ends of the manual keys 22 which are desirably black and white and correspond in arrangement to the keys of a piano. Each l'manual key 22 carries a switch actuator or operator 23 that is desirably in the form of a stiff spring finger terminating at its upper end beneath andl 1n contact with the sprm contact 10; the arrangement of the parts eing such that theuspring contact 10 will disengage itself from the contact 11 when the associate key 22 is in normal position or is not suiciently depressed to cause the finger 23 to move the contact 10 into engagement'with the contact 11. The spring 1Q also desirably exerts restoring force upon the key 22 underlying it though this function is preferably supplemented by the action. of ah additional spring 24. -The rear ends of the inanual keys and the switching -mechanism are normally covered by the hinged lid 25 that may be swun back when access is to be had to the switc ing mechal nism.

rlfhe operation ofthe instrument be readily understood from the foregoing de! scriptlon of the` drawin The sound producing bars- 19 are individual to different keys 22 and the magnets 1 to which such keys are individual and asjthese bars are desirably arranged in a chromatic scale sufv ficient depression of the keys will cause the corresponding bars to vibrate 'in the order in which the'keys are operated. Hitherto the switches controlled by the keys have been so mounted as to render them-r diiicult of access and as to require'much time to.

effect their removaland replacement so that if any of the switches broke ldown during a performance such performance would likely have to be discontinued. If the contacts 10 and 11 of any switch should become injured as a consequence of'sparking or otherwise, the .carrier 21 for such contacts may be quickly removed and a new /carrier with similar contacts may readilybe put into the position of the removed `carrier with the contacts 9 and 13 engaging the fixed c0n ,615

the preferred embodiment 4 N parting from the spirit ofmy invention, but v `having thus described my inventin I claim as new and desire to secure by Letters Patent the followng:-,

1. The combination lwith a bank of man- *ual keys of switches, each individualto al manual ey and located over 'the rear end thereof and having a movable contact-memberinterposed between the keyand the contact complemental to such contact-member; switch-actuating members upon the keys and projecting upwardly into en agement with said movable contact-mem ers and serving to bring these movable contactmembers into engagement with their complemental contacts when the keys are depressed; individual carriers for said switches; a mounting for saidcarriers; and connecting switches for connecting the aforesaid switches and having separable complemental parts upon the mounting and carriers.

2. The combination with a bank of manual keys; of switches, each individual to a manual key; switch actuatingmembers upon the'keys andengaging mova le members of the switches; individual carriers for said switches; a mounting for sa/id carriers; and

' connecting switches for connecting the aforesaid switches and having vseparable complemental parts upon the mounting and carriers. v

3. The combination with a bank of man# ual vkeys that are each individual to a. sound producing device; of switches,` each indi-` vidual to a manual key and operable therev by; individual carriers for said switches; a mounting for said carriers; and connectin switches having separable complemen parts upon the mounting and carriers.

4. The combination with a bank of man- -ual keys that areeach individual to a sound ual carriers for said -switches; and.l a niountf 5 .ing fonthe cairiers upon which such carriers v, are sepxu'ably supported.

[In wltness whereof, I helleunto subsoribe lily .na-me -this twenty-sixth dag-vv of Feli- .ruery, A. D. 1916. I

y* FREDERICK B. LITTLE.

' Witnessesz- I G. L. Gmac, Erm L. Wm.

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