US1827563A - Pneumatically operated pianoforte - Google Patents

Description

Patented Oct. 13, 1931 UNITED STATES {PATENT OFFICE ROBERT HENRY COLLEN, or BLACKWATER, ms: ENGLAND, ass roivoa or om:- HALF T JOHN BROADWOOD & sous Lnn'rm), or nonnomnlvenann PNEUMATICVALLY OPERATED rrmoronrn Application filed March 29, 1930, Serial No. 440,091, and in Great Britain July 25, 1929.

This invention relates to pneumatically operated pianofortes more particularly of the kind in which some of the valves controlling the note striking pneumatics are arranged in close proximity to the underside of the frame upon which the finger-keys are mounted.

This invention has for its object to provide an improved pneumatically operated pianoforte of the aforesaid kind wherein acc'ess may be had to the valves of all the valvular devices upon the removal of the fingerkeys, and mainly consists in arranging and securing the said valvular devices (which are preferably of the kind described and shown in the specification of Letters Patent N o. 1,-

773,662) in proximity to the underside of the said keys and in such position relatively to the space between the front rail and balance rail of the said frame that the valves of any of the said valvular devices can be removed and replaced through the said space upon the removal of the finger-keys situated above the valve, or valves, to which access is required.

If desired, the space between the frontrail 95 and the balance rail of the key-frame may be such as to permit the valves and their casings passing thercthrough so that access may be had to the actuating diaphragms beneath the said valves.

The accompanying drawing shows, in section, so much of a pneumatically operated pianoforte as is necessary to illustrate the application of the invention thereto.

Referring to the drawing the key-frame comprises a front rail 1, a balance rail 2, and a back rail 3, upon which the finger-keys 4 are mounted as hitherto. The key-frame is mounted on a key-bottom board comprising a front member 5 and side members 6, the latter of which are secured, in any suitable manner, to the sides 7, of the pianoforte casing and the former of which is of such width that it does not project inwardly beyond the rear, or inner side of the front rail 1 of the key-frame. Secured between the side mem-, bers 60f the key-bottom board and beneath the space between the front rail 1 and balance rail 2 of the key-frame is a main suction board 8 to the upper side of which are secured the valvular devices 9 which are shown as being of the kind described in the specification of Letters Patent No. 1,773,662. The valvular devices 9 are arranged in such position on the upper side of the main suction board 8 that any of the valves 10 may be removed and replaced through the space 11 between the front rail 1 and the balance rail 2 of the keyframe upon the removal of the adjacent finger-keys 4 and the removal of the nut 12 from the central post 13, the bridge-piece 1 1 and the cap-pieces 15, and if desired the valve tion of a tool through the space 11 between the front rail 1 and the balance rail 2 of the key frame when it is desired to remove and replace the valve casings 16 and permits the parts of the said valvular devices being more easily accessible when in position.

The note striking bellows, or motors, 19 are preferably arranged in tiers at the rear of the main suction board 8 and beneath the balance rail 2 and the back rail 3 of the key frame, passages 20 being formed in the said suction board by which communication between the respective bellows, or motors, and the valve chambers is effected.

The tubes 21 between the tracker-bar 22 and the purse pockets 23 of the valvular devices are preferabl led from the said tracker-bar to a space beneath the spool box 24 and then passed therefrom down the sides 7 of the pianoforte casing and through an opening in the key-bottom board 5 to a pocket 24 formed between the forward part of the main suction board 8 and the rear ortion of the front, member 5 of the keyottom board from which pocket they are finally led to the said purse pockets 23.

What I claim is I 1. In pneumatically operated pianofortes, the provision of means whereby access is obtained to any of the valvular devices for the adjustment, removal or replacement thereof upon removal of the adjacent finger keys of the instrument, the said means comprising the finger keys and key frame and Valvular devices, the key frame havin an unobstructed opening therein of sufliclent length and breadth to enable the whole of the said valvular devices to be passed therethrough on removal of the keys, the valvular devices being housed Within the said opening in a position adjacent to and beneath the underside of the said finger keys.

2. In pneumatically operated pianofortes, the provision of means whereby access is obtained to any of the valvular devices for the adjustment, removal or replacement thereof upon removal of the adjacent finger keys of the instrument, the said means comprising a key frame having a front rail and a balance rail spaced from said front rail, and a keyboard bottom having a front member and side members, in combination with a suction board spaced from said front member and secured between said side members of the keyboard bottom, leaving an unobstructed opening beneath the finger keys, and valvular devices secured to said upper side of the suction board between said front rail and front member on the one hand and said bali'lnce rail on the other and beneath the finger *eys.

In testimony whereof I have signed my name to this specification.

ROBERT HENRY COLLEN.

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