US2172355A

US2172355A - Piano-tuning wrench

Info

Publication number: US2172355A
Application number: US193795A
Authority: US
Inventors: Brady James Henry
Original assignee: ARTHUR W GARRETT
Current assignee: ARTHUR W GARRETT
Priority date: 1938-03-03
Filing date: 1938-03-03
Publication date: 1939-09-12
Anticipated expiration: 1956-09-12

Description

Sept. 12, 1939. .1;Y H. BRADY PIANO'TUNING WRENCH F'iled March 5, 1938 Patented Sept. 12, 1939 UNITED STATES PATENT OFFICE PIAN O-TUNING WRENCH Application March 3, 1938, Serial No. 193,795

2 Claims.

The invention relates to piano tuning wrenches, an object of the invention being to provide a practical balanced geared wrench of this description adapted to have more accurate and delicate control of the pins being tuned and t0 lessen the chances of breaking a piano Wire or string and the chances of loosening the tuning pins in the pin block of the piano by too much turning of said pins back and forth in accomplishing the tuning. Another object is to .adapt the wrench to be swung upwardly and downwardly upon an anchoring pin (not being tuned) with which the wrench is engaged, as a center, to lift the wrench from a pin being tuned and engage the same with other pins to be tuned within the radius of the body of the wrench and a slide extension thereof, without removal of the wrench from said anchoring pin. Other objects and advantages will appear hereinafter.

The invention consists in the novel construction and combinations of parts as hereinafter set forth in the claims.

In the accompanying drawing,

Figure 1 is a side view of the wrench, partly in section, the tuning pins being shown in dotted lines, and the wrench being shown as swung upwardly upon an anchoring pin as a center, .and the slide extension adjusted for engagement with another pin to be tuned, in dotted lines.

Figure 2 is a bottom plan view of the wrench.

In the drawing, the numeral I designates the body or support, of elongated form, having fixedly secured within a perforation 2, at one end thereof the upper end of .a depending sleeve 3, a

tubular shaft 4, rotatably engaging Within said sleeve and having at its lower end a socket piece 5, iixedly secured thereon and adapted to engage a pin the string of which is to be tuned, said tubular shaft having secured thereon at the upper end thereof a spur gear 6, resting upon said sleeve, a shaft l, rotatably engaging within said tubular shaft and being provided with an upper hand wheel 8, axially aligned with said socket piece, and a pinion 9, resting upon said spur gear. The body or support I has a stud i0, with which a pinion II and a spur gear I2 resting upon said support have rotatable engagement, said pinion ,and spur gear meshing respectively with the rst named spur gear and pinion, and being secured together to act as a unit. The support or body I is also provided with an elongated slide extension I3, the longitudinal edges of which are tapered to adapt said extension to engage a dovetailed groove I4 of said support, 55 said extension being provided at the free end thereof with a depending socket piece I5, adapted to engage another pin the string of which is to be tuned for anchoring purposes, said socket piece I5 having an upper reduced stem I6 projecting above the extension to form a handle or finger 5 piece and having threaded engagement with a perforation of the extension.

'I'he recess I'I of the socket piece I5 is of such oval or elongated form in cross section as to adapt the entire wrench to be swung upwardly 10 and downwardly upon the anchoring pin as a center to lift the wrench from the pin the string of which is being tuned and engage the wrench with other pins the strings of which are to be tuned, Within the radius of said support and its slide extension, without removal of the wrench from the anchoring pin. A pin I8 of said support engages a groove I9 of said extension to limit the movement of the latter in both directions. The rotatable shaft l is provided at its 20 lower end with a circumferential groove 20, with which a radial screw 2l of the socket piece 5 has engagement at its inner end, and upon removal of said screw, the shaft l, its hand wheel and pinion, may be removed. 25

The support or body I of the wrench and its slide extension I3 are both of generally flat or planular form and when the slide extension is adjusted inwardly, the inner end of said extension is located adjacent the depending sleeve 3, 30 and the depending socket piece I5 adjacent the outer end of said body, the dimensions of the parts being such as to be readily handled and controlled.

The parts being all centrally located with re- 35 spect to a single vertical plane and the socket piece 5 and the hand wheel 8 being axially aligned with each other, accurate tuning and delicate control are facilitated, being essential for a precision instrument of this description. 40 The hand wheel 8 being round and having a circumferential covering of rubber is always in the same position in contrast to a T-form handle, and is more readily grasped by the thumb and two or three ngers o'f one hand. The depend- 45 ing socket piece I5 at the free end of the slide extension aids in holding the Wrench in stationary upright position when in use.

In using the wrench, the socket piece 5, the recess of which is preferably of octagonal or star shape in cross section, is slipped on the pin the string of which is to be tuned, and the slide extension I3 being pulled out fully, the socket piece I5 thereof is slipped on the most distant pin that it will engage to hold or anchor the wrench in one position while the hand wheel is being turned to accomplish the tuning, following which the wrench is swung upwardly on the anchoring pin as a center to disengage the wrench from the pin the string of which has been tuned, without removal of the socket piece i5 from the .anchoring pin, and then swung downwardly on the anchoring pin as `a center to engage the next pin the string of which is to be tuned, this procedure being followed to tune those strings the pins of which are within the limits of the adjustment of the wrench.

I claim:

l. In a piano tuning wrench, a support having a depending sleeve, a tubular shaft rotatably engaging said sleeve and having a socket piece adapted to engage a pin to be tuned and a spur gear resting upon said sleeve, a shaft rotatably engaging within said tubular shaft and provided with an upper hand wheel axially aligned with said socket piece and a pinion resting upon said spur gear, said support having a stud, and a pinion and a spur gear rotatably engaging said stud and meshing respectively with said rst named spur gear and pinion, said support having a slide extension provided with a depending socket piece adapted to engage another tuning pin for anchoring purposes, the parts being all centrally located with respect to a single vertical plane.

2. In a piano tuning wrench, a support having a depending sleeve, a tubular shaft rotatably engaging said sleeve and having a socket piece adapted to engage a pin to be tuned and a spur gear resting upon said sleeve, a shaft rotatably engaging within said tubular shaft and provided with an upper hand wheel axially aligned with said socket piece and a pinion resting upon said spur gear, said support having a stud, and a pinion and a spur gear rotatably engaging said stud and meshing respectively with said rst named spur gear and pinion, said support having a slide extension provided with a depending socket piece adapted to engage another tuning pin for anchoring purposes, the parts being all centrally located with respect to a single vertical plane, the recess of the last named socket piece being of such elongated form in cross section as to adapt the entire device to be swung upwardly and downwardly upon the anchoring pin as a center to lift the wrench from the pin being tuned and engage the same with other pins to be tuned within the radius of said support and its slide extension.

JAMES HENRY BRADY.