IMPROVEMENTS IN SPEED GOVERNORS OR REGU- LATORS.
Year: 1878

page_text: LETTERS PATENT to Benjamin Joseph Barnard Mills, of the Firm of Harris
and Mills, of 23, Southampton Buildings, in the County of Middlesex, Patent
Agent, for the Invention of "IMPROVEMENTS IN SPEED GOVERNORS OR REGU-
LATORS. A communication from abroad by Alphonse Coignet, of Number 3,
Rue Rabelais, Lyons, in the Republic of France.
Sealed the 31st January 1879, and dated the 7th August 1878.
PROVISIONAL SPECIFICATION left by the said Benjamin Joseph Barnard
Mills at the Office of the Commissioners of Patents on the 7th August 1878.
BENJAMIN JOSEPH BARNARD MILLS, of the Firm of Harris and Mills, of 23,
Southampton Buildings, in the County of Middlesex, Patent Agent. "IMPROVE-
MENTS IN SPEED GOVERNORS OR REGULATORS." A communication from abroad
by Alphonse Coignet, of Number 3, Rue Rabelais, Lyons, in the Republic of
France.
When a vase of circular section containing a liquid is caused to turn around its
axis, the action of centrifugal force tends to throw the surface of the liquid out of
level, and to cause it to become hollow and to assume the form of a parabolic curve
which becomes more marked in proportion as the speed of rotation is increased.
Upon this well-known principle have been based apparatuses of observation serving
to determine the speed of rotation of a machine by the form of the parabola
obtained.
According to the present Invention, it is proposed to apply this principle to the
regulation of the speed of engines generally, by transforming by means of con-
nections conveniently arranged the variations in the level of the liquid into motion
communicating with the supply and cut-off apparatus. To this end it is necessary,-
Firstly. To choose a liquid which in small volume can develope work sufficient
to overcome the resistance of these apparatuses. Mercury is found to fulfil this con-
dition.

page_text: Secondly. To give to the vase which contains the mercury a special form, with a
view to facilitate the action of the mercury, and to obtain all the useful effect
possible with the least possible quantity of mercury.
Thirdly. To cause this liquid to follow rigourously the variations in speed of the
engine which is obtained by fixing in the interior of the rotating vase, wings, or
projections which, by preventing all slip of the mercury in the vase, communicate
to it forcibly all the variations of speed of the engine.
Fourthly. To transform the motion of the mercury into rectilinear motion of a
solid piece which is obtained by means of a float which may be central, and rest on
the bottom of the parabolic curve or annular, and follow the variations of the
extremities of the curve.
It is upon these principles that the two following examples are based:-
In the first example, the vase is fixed upon a vertical shaft which receives its
motion from the engine to regulate the float which is placed in the centre, and is
guided by a prolongation of the vertical shaft, and carries at its upper part a sleeve
which is connected with the supply and cut-off apparatus.
The vase has a wide open form, the section of which is a parabolic curve
depending upon the diameter of the vase and upon the speed of rotation, it is
furnished with an interior descending flange designed to prevent all accidental
escape of the mercury; the wings or projections are arranged at the circumference,
and are prolonged beneath the float throughout the space unoccupied by the motion
of the float.
In the second example, the vase is fixed, and the rotary motion of the mercury is
determined by that of the disc or wheel furnished beneath with wings or pro-
jections; this disc is fixed upon and receives its motion from a shaft which turns in
a fixed column; the float is annular, and contrary to the float in the former example,
is raised by the accelerations of speed, it also transmits its motion to the supply
and cut-off apparatus by a sleeve.
In these two examples, the form of the vase is such that the quantity of mercury
employed is only very little in excess of that which actually produces the work,
that is to say, to that.which would be displaced by the float during its maximum
course; this form can be determined by experience and by calculation.
The advantages of this kind of regulator or governor are the sensibility and
precision which result from the absence of all friction, the mercury working freely
in an open vase, without having to traverse either pipes or passages, and also the
economy of construction which results from the employment of a small number of
parts without precise connections between them.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Benjamin Joseph Barnard Mills in the Great Seal Patent Office on
the 7th February 1879.
BENJAMIN JOSEPH BARNARD MILLS, of the Firm of Harris and Mills, of 23,
Southampton Buildings, in the County of Middlesex, Patent Agent. "IMPROVE-
MENTS IN SPEED GOVERNORS OR REGULATORS." (A communication from abroad
by Alphonse Coignet, of Number 3, Rue Rabelais, Lyons, in the Republic of
France.)
When a vase of circular section containing a liquid is caused to turn around its
axis, the action of centrifugal force tends to throw the surface of the liquid out of
level, and to cause it to become hollow and assume the form of a parabolic curve
which becomes more marked in proportion as the speed of rotation is increased.
Upon this well-known principle have been based apparatuses of observation,
serving to determine the speed of rotation of a machine by the form of the parabola
obtained.
:.
According to the present Invention, it is proposed to apply this principle to the
regulation of the speed of engines generally, by transforming by means of con-
nections conveniently arranged, the variations in the level of the liquid into motion
communicating with the supply and cut-off apparatus. To this end it necessary,
Firstly. To choose a liquid which in small volume can develope work sufficient
to overcome the resistance of these apparatuses. Mercury is found to fulfil this
condition.
Secondly. To give to the vase which contains the mercury a special form, with a
view to facilitate the action of the mercury, and to obtain all the useful effect
possible with the least possible quantity of mercury.
Thirdly. To cause this liquid to follow rigourously the variations in speed of the
engine which is obtained by fixing in the interior of the rotating vase, wings, or
projections which, by preventing all slip of the mercury in the vase, communicate
to it forcibly all the variations of speed of the engine.
Fourthly. To transform the motion of the mercury into rectilinear motion of a
solid piece which is obtained by means of a float which may be central, and rest on
the bottom of the parabolic curve or annular, and follow the variations of the
extremities of the curve.
It is upon these principles that the two forms of apparatus represented in the
accompanying Drawing are based.
'
In the first arrangement represented at Figure 1, the vase V is fixed upon a
vertical shaft A which receives its motion from the engine to be regulated, the float
F which is placed in the centre is guided by a prolongation of the vertical shaft,
and carries at its upper part a “sleeve" m which is connected with the supply and
cut-off apparatus.
The vase has a wide open form, the section of which is a parabolic curve depending
upon the diameter of the vase and upon the speed of rotation, it is furnished with
an interior descending flange r, designed to prevent all accidental escape of the
mercury; the wings or projections v, v, are arranged at the circumference, and are
prolonged beneath the float throughout the space unoccupied by the motion of the
float.
In the second form represented at Figure 2, the vase e is fixed, and the rotary
motion of the mercury is determined by that of a disc or wheel c furnished beneath
with wings or projections d, d; this disc is fixed upon and receives its motion from
a shaft a which turns in a fixed column k, the float f is annular, and, contrary to
the float in the former example, is raised by the accelerations of speed, it also
transmits its motion to the supply and cut-off apparatus by a "sleeve " h.
In these two examples, the form of the vase is such that the quantity of mercury
employed is only very little in excess of that which actually produces the work

page_text: that is to say, to that which would be displaced by the float during its maximum
course, this form can be determined by experience and by calculation.
The advantages of this kind of regulator or governor are firstly, the sensibility
and precision which result from the absence of all friction, the mercury working
freely in an open vase, without having to traverse either pipes or passages, and also
the economy of construction which results from the employment of a small number
of parts without precise connections between them.
Having thus described the nature of the said Invention, and two modes in which
the same may be carried into effect, I would have it understood that what I claim
is constructing governors or regulators, with a float resting on the surface of a body
of mercury contained in an open vase and submitted to rotary motion, whereby the
level and form of the surface of the mercury is varied in proportion to the rotary
speed given thereto, and the float is thereby caused to rise and fall, and regulate
the speed of the engine or machine in manner substantially as herein shown and
described.
In witness whereof, I, the said Benjamin Joseph Barnard Mills, have hereunto
set my hand and seal, this Seventh day of February, in the year of our
Lord One thousand eight hundred and seventy-nine.