US1558817A

US1558817A - Piano action

Info

Publication number: US1558817A
Application number: US650380A
Authority: US
Inventors: Koehler Charles
Original assignee: Individual
Current assignee: Individual
Priority date: 1923-07-09
Filing date: 1923-07-09
Publication date: 1925-10-27
Anticipated expiration: 1942-10-27

Description

C. KOEHLER 'Oct. 27, 1925. 1,558,817

PIANO ACTION Filed July 9, 1923 6;? i M %A RNEYL/ Patented Oct. 27, 1925.

UNITED STATES 1,558,817 PATENT OFFICE.

CHARLES KOEHLER, or CHICAGO, ILLINOIS.

PIANO Application filed July 9,

To all whom it may concern:

x Be it known that I, CHARLES Konrinnn, a citizen of the United States, residing at Chicago, in the county of Cook and State of Illinois, have invented certain new and useful Improvements in Piano Actions, of which the following is a specification.

This invention has to do with certain improvements in piano actinsthat is, the mechanism for transferring the movement of the finger key of the piano to the hammer or striker.

One object of the invention is to provide an arrangement whereby the movement of the key is transferred to the hammer by an arrangement of parts which eliminates the necessity of using expensive materials such as buck-skin or specially prepared leather on the surfacesof certain of the parts which come into contact. In this connection, it has been customary in the past to face certain of the parts with leather of suitable nature, so that the proper action will be given both during the operation of transferring movement to the hammer and the further operation of disengaging the parts so that the hammer will strike freely. This leather, so

used in the past, is expensive and requires great care and skill in placing it on the parts so as to secure the proper action.

According to the present invention I have provided anarrangement whereby the movement is transmitted between the parts by the use of silken cords or bands and without the necessity of using this specially character ized leather. At the same time I have pro- Vided an arrangement' whereby the action itself is very greatly improved and whereby the cost of construction is considerably lowered and the touch made much lighter.

A further feature of the invention relates to the provision of an improved means whereby the action may be very easily adjusted so as to secure proper striking of the hammer with the desired lightness of touch. According to this feature of the present invention, the exact position of the hammer at which the same is disengaged from the key lever may be easily adjusted so as to ensure accurate hammer movement combined with lightness of touch and proper recoil.

A further object of the invention is to combine all of the foregoing features in an arrangement of simple construction and great durability and which can be cheaply manufactured and assembled,

ACTION.

1923. Serial No. 650,380.

Other objects and uses of the invention will appear from a detailed description of the same which consists in the features of construction and combinations of parts hereinafter described and claimed.

In the drawing:

Fig. 1 shows avertical elevation of a piano action embodying the features of the present invention, the same being shown in the position which the parts occupy with respect to the piano frame when the hammer is at rest, the finger key beingbroken away so as to shorten up the figure;

Fig. 2 shows a perspective view of the butt on the lower end of the hammer. stem; and 1 Fig. 3 shows a perspective view of the upper portion of the operating trigger together with the cord which engages the aforesaid hammer butt.

In the construction illustrated in the drawing, the finger key is designated by the numeral 4. It is pivoted to the frame bar 5 on the pin 6, and the rear end of the key lever 4 normally stands at rest against a cushion of felt or the like 7 on the top surface of a frame bar 8. A pressure block 9 is threaded upon the upper end of a stem 10 on the rear 4 end of the key lever 4 so that said pressure block can be raised and lowered for purposes of adjustment.

The cord or string is designated by the numeral 11. The hammer 12 is made of felt or other appropriate material and is carried on the upper end of the hammer stem 13. Normally the hammer stem 13 rests against a felt or cushion facing 14 on the frame bar 15 as shown in Fig. 1.

The lower end of the hammer stem 13 is mounted within a hammer butt 16 pivoted on the pin 17 which passes through a loop of metal strap 18 secured to the frame bar 19. The arrangement is such that the hammer butt 16 may oscillate perfectly. free on the pivotal point 17.

A wippen- 20 has its rear end articulated on the pivot point 21 carried by the bracket lower surface of the wippen 20, and the cushposition to receive the pressure from the block 9 and also fully protects the eushion-- ing block 23 at its ends, as well as in its central portion.

A jack 25 has its lower end pivoted at the point 26 to a bracket 27 which reaches up.- wardly from the wippen 20. This jack 25 is preferably of bell crank shape, as shown in Fig. 1, and a spring 28 is provided between the under surface of the short arm 29 of said bell crank and the top surface of the wippen 20. This-spring, therefore, tends to tilt the'jack rearwardly so as to carry its upper portion 30 towards the hammer butt The hammer butt itself is preferably recessed in its lower front corners, as shown at 31 in Fig. 2, so as to establish a relatively narrow vertically extending forwardly reaching tongue 32, as clearly shown in said figure. This tongue is in turn slotted inwardly as shown at 33, said slot extending in a direction substantially at right angles to the line of thrustof the jack 25' when thewippen 20vis raised. The forward corner 34 of the tongue 32 is made relatively sharp at the upper surface of the slot 33.

The, upper portion 3O of the jack 25' is bifurcated as shown at 35in Fig.3 so as to establish the fingers 36and 37 which are of sufiicient separation to receive the tongue between them. Also the depth of the bifurcated portion is suiiicient to cause the body portion of the jack to clear the tongueat all times.

Stretched between the upper ends of the

fingers

36 and 37 is a cord 38' of suitable materialof, proper s'izeto work easily within the slot 33 of the tongue. This cord 38 may be of anyv suitable material, but experience shows that silk is admirably adapted for use 'in the present invei'ition, and I, therefore,

prefer to use the same. As a matter of convenience in construction, ,I prefer' to form a transverse slot 39 across the front face of theupper portion 3(l'of' the jack 25, so that the ends of the cord 38jcan be carried dolwn interposed into said slot 39 and there held in place asby means of he or the like 40; Located above the heel portion 29' of the jack is. a frame bar 41 into which isl-threaded a stem 42, the lower end of whioli' carries a block 43 preferably faced with felt or the like 44 on its bottom surface. This block 43 can be raised and lowered .in' a very simple manner according to this constructionv i The hammer butt 16' carries ferwardly projectinggstein 45': on-the end of" which is a block, 46' plifeiahly faeecl with: felt or the like 47'. A recoiibieck' 48 is carriedbythe upper end of a stem 49011 the end portion of the wippen 20, said recoil block 48 being preferably surfaced with felt or' the like 50 in positionrto contact against the felt surface 47 of the block 46. 5

The block 46 has a finger 51 on its lower end which is preferably surfaced with a block off'elt or the like 52, and the upper portion 30 of the jack 25 is preferably provided with a cushioning block 53 of felt or the like in position to engage'tho block. 52 just above referred to. V erably so arranged that the block 53 overlies the slot39 in the upper portion of the ack The operation of this device is as follows: Upon quickly depressing akey lever 4, its rear end will rise so as to move the wippen 20' upwardly. The jack '25 will thus be forced up and the cord 38 will act upon the tongue of the hammer butt 16 so as to commence the striking movement of the'hammer. The engagement of the cord 38 with The parts are pref-- the tongue 32will continue until the heel 29 engages the knock off surface 44 of the'block 43 on the stem 42 and the position of such engagement can be readily adjusted by threading the stem up or down.

M As soon as the heel 29- engages the stop just referred to, any further rise of the wippen 20 will not only'continu'e to throw the hammer towards the string ll, but will cause the jack 25 to swing away from the block 16, so that the cord 38 will very quickly ride from under the corner 34 of'the' tongue 32. Instantly that this takes place, the arm andjack are completely disengaged, and the further throw of the hammer is dependent entirely upon its previously acquired momentum.

Further rise of the wippen 20 carries the recoil block 48 towards the hammer butt 16 andin'to position to receive impact from the block 46 which extendsiearwardly from the hammer butt 16. Consequently the recoil block 48 stands in posit-ion'to takethe recoil of the hammer andcushion same as soon as the hammer flies back from the string 11. The. forward movement ofthe wippen 20 and associated parts is limited by engage- I r ment ofthe' stem 49 with thefraine bar 41. at the sides of the fingers 36 and 37' and f l cord'3'8 of the jack 25 will be caused to hook As the wippen 20 drops downwardly the only a single embodiment of the featuresiof my" invention, stillI do not limit myself to the same except as I may do so'iirthe claims.

I claim:

1. A piano action comprising in combination a hammer, a hammer stem therefor, a hammer butt, a pivotal mounting therefor, the lower portion of said hammer butt having a relatively narrow tongue, a wippen pivoted beneath the position of the hammer butt, a jack pivoted to said wippen and having its upper end bifurcated and adapted to receive the tongue of the hammer butt, there being an inwardly reaching slot in said tongue, a cord between the bifurcations of the jack adapted to engage said slot, a sidewise projecting heel on the jack, a stop on said heel. for limiting its upward movement, and means for adjusting the elevation of said stop with respect to the wippen substantially as described.

2. A piano action comprising in combination a hammer butt, a hammer connected thereto, a pivotal mounting for the hammer butt, a relatively narrow tongue on the hammer butt, there being an inwardly reaching slot in said tongue, a wippen pivoted beneath the position of the hammer butt, a jack pivotally mounted upon said wippen, the upper portion of said jack being bifurcated, a cord extending between the bifurcations and adapted to enga e the slot of the tongue, there being a sidewise projecting heel on the tongue, and means for limiting the upward movement of said heel, substantially as described.

3. In a piano action, the combination of a hammer butt, a pivotal mounting therefor, an inwardly reaching transverse slot in said hammer butt, a wippen pivoted beneath the position of the hammer butt, a jack pivotally mounted upon said wippen, the upper portion of said jack being bifurcated, a cord extending between the bifurcations of the jack and adapted to engage the slot of the hammer butt, and means for causing the jack to swing away from the hammer butt at a predetermined position in its upward movement, substantially as described.

4. In a piano action, the combination of a hammer butt, a pivotal mounting therefor, there being a transverse inwardly extending slot in the hammer butt, a jack having its upper portion bifurcated, a cord extending between the bifurcations of the jack, a pivotal mounting for the ack, means for moving said pivotal mounting vertically, and means for swinging the jack on its pivotal mounting when said pivotal mounting reaches a predetermined elevation, substantially as described.

CHARLES KOEHLER.