IMPROVEMENTS IN MACHINES FOR TURNING OVER LEAVES
Year: 1879

page_text: LETTERS PATENT to Konrad Trobach and Franz Rosenzweig, of Berlin, Prussia,
Engineers, for the Invention of "IMPROVEMENTS IN MACHINES FOR TURNING
OVER LEAVES."
PROVISIONAL SPECIFICATION 'left by the said Konrad Trobach and Franz
Rosenzweig at the Office of the Commissioners of Patents on the 13th May
1879.
KONRAD TROBACH and FRANZ ROSENZWEIG, of Berlin, Prussia, Engineers. "IM-
PROVEMENTS IN MACHINES FOR TURNING OVER LEAVES."
This Invention refers to that kind of leaf turners in which a series of levers are
employed, and made to operate successively to turn the leaves of a book of music or
of any other book. The apparatus is so arranged that when folded together it
assumes the shape of a book or map, and when opened, it can be conveniently
placed upon the ordinary support fitted on all pianos for the purpose of holding the
music. The separate levers are forked to receive the leaves which it is desired to
turn, and they are mounted on a diagonal shaft so that before being turned they
extend vertically or nearly vertically upward, and after being turned they assume a
horizontal position, holding the turned leaf only at its lower edge. The turning of
these levers and consequently of the leaves is effected by springs strung on the
diagonal shaft, and across or in front of these levers is laid a locking bar which is
pivotted at its outer extremity. Each time that the performer wishes to turn over
a leaf he depresses the locking bar sufficiently to liberate one lever, which then,
impelled by its spring, turns over from right to left.
This liberating motion is imparted to the locking bar either by direct traction on
a pedal or key acted on by the finger, or it may be actuated by the hand or the
foot of the performer below the key board, in which case a fine metallic spring
reaching from the locking bar to the pedal is passed between two notes.
A spring clip is placed over the edges of the leaves to be turned, from under
which each leaf is pulled away as it is turned. This clip serves to hold the
following sheets which might be partly drawn along by the suction of air created
by the rapid turning.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Konrad Trobach and Franz Rosenzweig in the Great Seal Patent
Office on the 13th November 1879.
KONRAD TROBACH and FRANZ ROSENZWEIG, of Berlin, Prussia, Engineers. "IM-
PROVEMENTS IN MACHINES FOR TURNING OVER LEAVES."
This Invention refers to that kind of leaf turners in which a series of levers are
employed, and made to operate successively to turn the leaves of a book of music
or of any other book. The apparatus is so arranged that when folded together
it assumes the shape of a book or map, and when opened, it can be conveniently
placed upon the ordinary support fitted on all pianos for the purpose of holding
the music. The separate levers are forked to receive the leaves which it is desired
to turn, and they are mounted on a diagonal shaft so that before being turned
they extend vertically or nearly vertically upward, and after being turned they
assume a horizontal position, holding the turned leaf only at its lower edge. The
turning of these levers and consequently of the leaves is effected by springs wound
on the diagonal shaft, and across or in front of these levers is laid a locking bar
which is pivotted at its outer extremity. Every time the performer wishes to turn
over a leaf be depresses the locking bar sufficiently to liberate one lever, which
then, impelled by its spring, turns over from right to left.
This liberating motion is imparted to the locking bar either by direct traction on
a pedal or key acted on by the finger, or it may be actuated by the hand or the
foot of the performer below the key board, in which case a fine metallic spring
reaching from the locking bar to the pedal is passed between two notes or keys.
A spring clip is placed over the edges of the leaves to be turned, from under
which each leaf is pulled away as it is turned. This clip serves to hold the
following sheets which might be partly drawn along by the suction of air created
by the rapid turning.
In order that the Invention may be more clearly understood, we will describe it
conjointly with the five Figures of the accompanying Drawing, in which,―
Figure 1 is a front elevation of the apparatus placed ready for use on a piano.
Figure 2 is a plan of the keys of the piano showing in dotted lines some parts
used when the apparatus is to be actuated by the knee or foot of the performer.
Figure 3 is a front elevation showing the principle parts of the mechanism on
a larger scale.
Figure 4 is a section on the line A, B, Figure 3, and
Figure 5 is an elevation of a detail.
a is the case of the apparatus formed in the shape of a music map so that it
can be conveniently opened and closed. On the inside thereof is mounted the
bottom plate of the turning mechanism [proper. This plate b supports the
bearings in which the diagonal axis d is adapted. The axis d carries the collars
e on which the turning levers fare fixed.
Spiral springs g are so arranged on the axis d that they constantly exert a
pressure on the collars, tending to turn the latter from the right toward the left;
is a lever firmly fixed on the ratchet wheel i by means of the sleeve k; lis a
stopping piece connected with the pieces 12 which turns loosely on the pin m, on
which latter turns also the sleeve & with its ratchet wheel i and lever h. These
parts are held in position by means of the screw n, as shown in Figures 3 and 4.
The music leaves are turned in the following manner :-The leaves which it is
desired to turn are placed on the supports o fixed on the interior of the map.
After having disengaged the stop and lowered the lever k, there is placed,
commencing from below, a turning lever under each sheet of music. These turning
levers are provided with forks p into which the music leaf is introduced, and
after this introduction the lever is held in place by turning the lever h upward
so as to hold it. The object of the fork, which in consequence of its comparatively

page_text: very small width does not cover the notes, is to hold the following leaf, which
might be drawn along by the current of air produced when the upper leaf is
turned. The pivotted spring u fastened to the map, see Figure 1, serves for the
same purpose for the last sheet. The entire number of leaves which it is desired to
turn being thus introduced and held in the levers, and the stop being again
engaged, this latter part is caused to operate by means of the liberating mechanism
adapted to the map; this liberating mechanism on being moved by the hand of the
performer causes through a cords connecting it with the stop the lever h to
descend the distance of one tooth, whereby a turning lever is liberated, which latter
then in obedience to the force of the spiral spring g is turned from right to left
with its music sheet into the first position, and holding this sheet at the under edge
without covering the notes. The stop is pushed back by the spring ", whilst the
lever h remains in the position into which it has been moved; these operations are
repeated until all the leaves are turned.
The liberating mechanism which is operated by hand consists of wires fastened
at the right and left lower edges of the map; the ends of these wires are turned
over so as to form rings in which are introduced the wooden rods r, which pass
also through the ring attached to the end of the liberating cord s. The dove tailed
ends of these rods are then joined together, and a sleeve is slipped over them so as
to hold them securely together. By this arrangement the performer can while
playing operate the liberating apparatus with his right or left hand on the entire
width of about 4 octaves, by simply exerting a slight pressure at any convenient
point, exactly as if he were touching a key of the piano. Besides, we have
arranged a pedal motion, as shown in Figures 1 and 2, operating through between
the keys. This pedal motion is constructed as follows:-Below two keys 1 and 2
coincident with the space between them is made a hole in the bottom of the piano,
through which is passed a piece of watch spring of 3 of an inch width. This
spring establishes a communication between the mechanism for liberating by hand,
and a pedal placed in suitable position to be operated by the performer, for instance
as shown in Figure 1, by his knee; in this manner it is rendered unnecessary to use
the hand for effecting the liberation. The piece of watch spring which passes
through between the rear parts of the keys prevents in no way the free motion of
the keys 1 and 2, and the performer is by no means molested in his play by the
rod r which hangs down in the rear in a horizontal position.
Having thus described the nature of our Invention as well as the best incans we
are acquainted with for carrying the same out in practice, we claim,-
1st. A leaf turning mechanism for inusic arranged in the shape of a music map.
2nd. The diagonal shaft d by which the position of the turning levers is
determined, so that the latter before being turned have a vertical or nearly vertical
position, and after being turned a horizontal position.
3rd. The hand liberating mechanism a, r, s, and
4th. The pedal mechanisin composed of the watch spring passing through
between two keys and through a hole in the bottom of the piano, and connecting
the hand liberating mechanism with a pedal, which latter may be operated by the
knee or foot of the operator.
In witness whereof, we, the said Konrad Trobach and Franz Rosenzweig, have
hereunto set our hands and seals, this Thirteenth day of November, in
the year of our Lord One thousand eight hundred and seventy nine.