Year: 1886

page_text: I ALFRED JULIUS BOULT of 323 High Holborn, in the County of Middlesex,
Engineer, do hereby declare the nature of this invention (a communication from
Paul Theophil Balthasar Berner of Berlin, in the German Empire) and in what
manner the same is to be performed, to be particularly described and ascertained in
and by the following statement: -
The tension and tuning mechanisın, forming the subject of this invention, serves
to give the tension to the strings as well as to enable a most delicate and exact
tuning of the pianoforte or piano to which it is applied, and has the great
advantage, that it can be applied to all existing pianofortes or pianos of any
construction with ease and it is immaterial whether the instrument be single chord,
bichord or trichord.
The accompanying drawings represent the mechanism as applied to a trichord
instrument, and
Figure 1 represents a side elevation.
Figure 2 a plan.
Figure 3 a section on line x x of Figure 1.
Figure 4 a section on line y y of Figure 2.
Figure 4 the same without rollers and pegs.
Figure 5 is front elevation.
Figure 5° a section on line of Figure 3.
Figure 6 represents the peg.
Figure 7 shows the worm wheel and string groove of the roller.
Figure 8 is a side view of the tuning block.
This tension and tuning mechanisu consists essentially of three parts i.e., the
block A, the tension and tuning roller B with its worm wheel cut in, and the peg C
with the worm.

page_text: The block A, rectangular in section, is provided with two lateral flanges a a,
which serve for the fastening of the block A to the pegboard D of the instrument,
by the screws a¹ al and has horizontal borings bbb for the tension and tuning
rollers B B B and vertical borings c c c for the pegs CC C.
The roller B consists of a small cylindrical or slightly conical steel or wrought
iron piece and is so much in excess of the width of the block A that the string
groove b' stands out from the block when the roller is introduced. This annular
string groove b' is provided with a hole b' which reaches into the central hole b³ is
for the introduction and fastening of the string. The outer mantle of the cylinder B
is provided with a recessed peripheral screw thread c¹.
.The peg C.has at its upper end a square head and at its lower end a pin c³, while
the middle of the peg is provided with a worm thread c' for the worm wheel of the
roller. The pin c³ serves to give the peg C a proper support when it is being
turned.
The roller B is introduced into the borings b of the block A and is held therein
by the peg C and its worm. In bichord or trichord instruments the centres of the
rollers B must be so arranged that the string of the hind rollers pass under the
roller and string in front, see Figure 1, the strings are then brought into their
proper horizontal or vertical position by the guide Ď¹.
By turning the peg C, by a key placed on the square head c² any desired move-
ment is given to the roller B which permits a most delicate and exact tuning.
Having now particularly described and ascertained the nature of the said
invention and in what manner the same is to be performed as communicated to
me by my foreign correspondent I declare that what I claim is
1. A tension and' tuning roller such as B provided with a recessed peripheral
screw thread c¹ and an annular string groove b¹ and held in the borings b of the
block A by the screwed peg C substantially as specified.
2. The combination with the tension and tuning roller B provided with the
recessed peripheral screw thread c³ the annular string groove 6' and the boring b
carried in block A of the peg C with screw thread and pin e³ to give the peg C a
support in A substantially as and for the purpose specified.
Dated this 10th day of Anil 1906