US1403401A - Combination balance-rall pin and key for pianos - Google Patents

Description

F. L. GEORGE.

COMBINATION BALANCE RAIL PIN AND KEY FOR PIANOS.

APPLICATION FILED OCT. 11, 1920.

1,403,401 Patented Jan. 10, 1922.

//v VENTOR FRA NK L. GEO/76E PATENT OFFICE.

FRANK L GEORGE, OF LOS ANGELES, CALIFORNIA.

COMBINATION BALANCE-RAIL PIN AND KEY FOR PIANOS.

Specification of Letters Patent.

Patented Jan. 10, 1922.

Application filed October 11, 1920. Serial No. 416,115.

To (ZZZ whom it may concern:

Be it known that I, FRANK L. GEORGE, a citizen of the United States, residing at Los Angeles, in the county of Los Angeles and tate of California, have invented new and useful Improvements in Combination Balance-Rail Pins and Keys for Pianos, of which the following is a specification.

This invention relates to piano keys and the balance rail pins forming mountings for the keys.

It is the object of'the invention to provide a construction whereby piano keys may be readily mounted upon their pins and the keys then accurately leveled and spaced with great ease. It is a further object of the invention to provide for thisleveling and spacing of the keys without necessitating the removal of the keys from their pins. It is a still further object of the invention to provide a construction wherein the keys are balanced by placing the fulcrum in the center of the key instead of at the extreme bottom edges of the same and to also provide for strengthening the keys at their balanced points. The improved construction also eliminates to a great extent the friction between keys and their pins and generally effects a saving of labor, and material in installing and adjusting piano keys.

In the present construction of piano keys and their balance pins great inconvenience has been experienced due to the wearing down of the felt bushings for the keys. This wearing of the bushings has caused the keys to become unsteady upon their pins and as a result the action of the keys has been uncertain. Furthermore, the present practice of leveling keys by removing the latter from their pins and inserting paper washers until the keys are properly leveled has produced very unsatisfactory results and has also caused a great expenditure of time and labor.

In, the present construction the keys are properly positioned. and the wear is taken up without removing the keys from their pins and by adjusting caps which are a piano key showing the balance rail and a port-ion of the key in vertical section.

Fig. 3 is a bottom plan view of the piano key taken on the line 33 of Fig. 2.

Fig. i is an end view of the balance pin employed in the improved construction.

Fig. 5 is a bottom view of the cap for the balance pin.

In the drawings is shown a balance rail 1 which may be of usual construction, and one of the keys mounted upon the same is shown at 2. The key 2 is bored from its un der side to form the elongated recess 3, and the forward portion of this recess is provided with a countersunk recess 4 in the base of the same. A bore 5 of reduced diameter extends from this countersunk recess as is the usual construction. The key guide isv provided with an opening 10 extending through the same in ahnement with the portion of bore 3 in rear of the countersunk re-' cess 4, and said key guide is also provided with an elongated slot 11 communicating with the opening 10 and extending lengtlr wise of the key guide in alinement with the countersunk recess 4 The sides of this elongated slot maybe provided with usual felt pads 12.

The balance pin upon which the key is mounted is shown in detail in Figs. 2 and 4. The pin consists of a shank 14 which is driven into the top of the balance rail in accordance with the usual practice. Above this shank the pin flares outwardly from opposite sides of the shank to form the shank portion 15 of increased width. Above this portion of the pin athreaded shank 1.6 is provided, which is of approximately the same diameter as the shank end lei. In practice the pin is mounted in the balance rail so that the shank portion 15 is positioned with its increased width extending transversely of the balance rail and in the direction of the length of the key to be mounted upon said pin.

A cap 18 is screw seated upon the threaded end 16 of the balance pin, said cap comprisin a split sleeve arranged for frictional threaded engagement with the pin, and a head 19 above said sleeve and extending over keys are properly leveled. ,pads 12become worn so that there is atend r balance pins and the keys.

the end of the balance pin. The upper surface of this head is transversely slotted as shown at 20 in order that it may be engaged by a screw driver for adjusting the cap upon the balance pin through its threaded connection. t Y

For positioning the key 2 upon its balance pin the cap '18 is inserted through opening into the bore 8; and by then moving the key rearwardly with relationto'its balance pin the portion of the pm is received in slot 11 and the cap 18 is moved into allnement with the countersunk recess 4:.- The key is then lowered upon its balance :pm

until the head 19 of the cap lS is seated in the recess a; The key is now held against "lateral displacement by engagement of padded sides of slotll against the sides of the portion 15 of the balance pin and at the "same time the key is fulcrumed upon the balancepin through engagement of the head 19 of the cap for the balance pm against the base of recess a. The countersunk recess 4 is positioned approximately midway between the upper and lower surfaces of the key 2 and the fulcrum for the key is thus provided at a point'where the movement of the key upon itsbalance pin willcause the minimum movement between the parts; As a result the frictionalwear between the key and its balance pin is reduced materially.

VAfter the keys have been positioned upontheir balance pins; in order-to level-the same; it is only necessary to inserta'screw driver-through bore 5 so as to engage-the V grooves 20 0f the heads of caps 18, andthe 1 caps forthe balance pins may then be readily raised'and lowered upon the'pins until the ency iof the keys to move laterally upon their balance pins, the pins are turned in the balance railuntil the widened portions 15 of the, pins engage thepadded sides of slots 11 ,so asito take up the play between the Various changes may be made without de parting from the spirit of the invention as claimed. I

What is claimed is: I 7 V l. Ina piano, the combination with a bal- When v the felt ante rail pin, of a key fulcrumed at a point intermediate its'top and bottom faces upon said pin, and said key being provided with an opening whereby the" balance railin may be adjusted without removing-the (ey from said pin.

,2. In a piano, the combination witha bal ance rail pin havin a cap adjustable along said pin, of a key *ulcrumed at a point intermediate itsjto'p and bottom faces upon said cap.

Ina piano, the combination with a balance-rail pin having a cap threaded upon its end for adjustment relative to said pin, of a key fulcrumed at a point intermediate its top and bottom faces uponsaid cap.

41-. Ina piano, the combination with a balance rail pin having a cap threaded uponits end for adjustment relative tosaid pin,- of a key fulcrumed at a point intermediate its top and bottom faces upon said cap, said key having a bore extending through the same to its top surface and adapted to receive a tool for engaging said cap to eifect adjustment of the latter. c 7

5. In a piano, the combination with a balance'rail pin, or" a key fulcrumed upon said pin, said pin having a portion of increased trans-verse width, and said key having an elongated slot-through which-said" pm portion extends, and means adapted to be engaged by a suitable tool for turning said pin to cause engagement of said portion ofincreased width with the walls of said slot. I i V 7' 6. A piano balance-rail pin comprising a shank having lateral projections on its body 1ntermed1ate lts ends, and a cap adjustably positioned on the upper end of said shank. v V

7.' The combination withv a'piano key provided at a point intermediate its top and bottom surfaces with a bearing and with a slot below said bearing, of a balance raillpin having a portion of increased transverse wldth arrangedon the slotted portion of the key and its upper end seated in the bearing in said key.

In testimony whereof I have signed my; 7 name to 'th1s speclfication.

, V'FVRANKL. GEORGE.

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