US314195A - Ferdinand polster - Google Patents

Description

(No Model.)

F. POLSTER.

UPRIGHT PIANO ACTION. No. 314,195. Patented Mar. 17, 1885.

Will/WWW UNITED STATES PATENT Orrrca.

FERDINAND POLSTER, OF BALTIMORE, MARYLAND, ASSIGNOR TO IVM. KNABE & OO., OF SAME PLACE.

UPRlGHT-PIANO ACTION.

SPECIFICATION forming part of Letters Patent No. 314,195, dated March 17, 1885. Application filed April 14, 1884. (No model.)

To all whom, it may concern.-

Be it known that I, FERDINAND PoLsrEn, of Baltimore, in the county of Baltimore and State of Maryland, have invented certain new and useful Improvements in Upright-Piano Actions; and I do hereby declare the following to be afull, clear, and exact description of the invention such as will enable others skilled in the art to which it appertains to make and use the same.

My invention relates to improvements in repeatingactions for upright pianos; and it consists partly in a novel construction and arrangement of the hammer-butt and back check; secondly, in the peculiar construction of the jack which operates in connection with the hammer-butt and back-check; thirdly, in

the arrangement of an auxiliary spring-jack having both a longitudinal and lateral movement.

It consists, finally, in details of construction and arrangement fully hereinafter explained.

The drawing shows a side elevation of a portion of a piano-action, the hammer-rail, sounding-board, and ham mer-rest being shown in section.

A represents one of the key-levers of an upright piano-forte.

B is the lifter connected to the inner end of the key, and bearing on the lower surface of the fly-lever O, the latter being pivoted on a hanger secured to the hammer-rail D.

A double-forked standard, a, is secured to the hammer-rail, at one end of which is pivoted the hammer-butt E, and at the other the damper E The hammer E is operated by the jack or fly G, pivoted to the lily-lever O. The uppcr end of the jack bears against the hammer-butt and operates the hammer in the usual manner. H is the hammer-rest, and I the sound ing-board.

A back-cheek, J, is adjustably secured to the butt E by means of a screw-rod, e. The surface against which the jack bears is inclined, as shown, and suitably deadened. At the upper end of the jack is an angular projection, f, the inclined side of which is adapted to fit closely against the corresponding incline of the back-cheek when the key is depressed. firmly against the butt as the hammer is in the act of striking the string. The movement of the jack may therefore be easily limited or increased by proper adjustment of the backcheck.

K represents an auxiliary jack connected to the main jack G, but having a motion independently thereof. A sliding screw-tln'eaded rod, k, has a head, k, which rests against the head ofjack G, and, like it, bears on the hammer. This rod passes through perforated brackets Z Z on the jack, and a bracket, Z on the hammer-rail. The movement of the rod L is limited by a pair of check-nuts, m m, one of which works on the rod below the bracket Z, the other below the bracket Z, a spiral pressure-spring being mounted on the rod between the bracket Z and a button, a, which regulates its pressure. \Vhen the key is depressed and the jack G is raised, the rod It moves with it a distance limited by the position of the nut m, and as the head It bears on the butt such movement tends to raise the hammer. XVhen the projection on the jack bears on the inclined face of the back-check, the head it is brought directly beneath the butt. WVhen the key is released, the pressure spring tends to throw thejack downward.

The auxiliary jack is prevented from moving by turning the nut m up to bear against the bracket Z".

Having fully described my invention, "what I claim as new, and desire to secure by Letters Patent, is-

1. In a piano-action, the combination, with a hammer and hammer-butt, of a back-check, a pivoted jack, and an auxiliaryjack having a movement independently of the pivoted jack, substantially as set forth.

2. In a piano-action, the combination, with a hammer-butt and adjustable back-check, of a pivoted jack and a spring-actuated auxiliary jack connected to the main jack, but having a motion independently thereof.

3. In a piano-action, the combination, with a hammer, hammer-butt, and an adjustable back-check having an inclined face, of the The opposite edge of the jack bears In testimonywhereof I have signed this specification in the presence of two subscrib-- IO ing witnesses.

pivoted jack having an angular projection, and the auxiliaryjaek connected to said pivoted jack, but having a motion independently thereof, substantially as set forth.

5 4. The combination, with the jack G and hammer, of the sliding rod 7:, the spring, and the adjustable check-nuts, substantially as described.

FERDINAND POLSTER.

Witnesses:

BATZLER, En. RAINE.

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