IMPROVE- MENTS IN GOVERNORS
Year: 1864

page_text: PROVISIONAL SPECIFICATION left by Michael Henry at the Office of
the Commissioners of Patents, with his Petition, on the 25th June
1864. A communication from abroad by Léon Foucault, of 33,
Boulevart Saint Martin, Paris, France.
I, MICHAEL HENRY, of 84, Fleet Street, in the City of London, Patent
Agent, do hereby declare the nature of the said Invention for "IMPROVE-
MENTS IN GOVERNORS," communicated to me from abroad by Léon Foucault, of
33, Boulevart Saint Martin, Paris, France, to be as follows:-
This Invention relates to an improved governor for which a Patent was
obtained by William Clark, No. 3479, dated 30 December 1862, as a com-
munication from the said Léon Foucault, and the present application has
for object,
-
First, to set forth general conditions for rendering a governor isochronous,
showing that such isochronism depends on a very simple relation between the
work of the weights or springs, or both, and the movement of the collar
or ring.
Secondly, to explain certain arrangements for carrying into practical effect
conditions conformable with the principles set forth.
Thirdly, to explain how by substituting springs for the weights a governor
will be constructed independent of variation of weight, and applicable on
board ship.
Fourthly, to describe a governor in which weights and springs are com-
bined, so as to obtain an isochronic action with extreme simplicity.

page_text: The general condition of isochronism in a governor is this, that the work of
all the weights and counterweights or springs (or both weights and springs)
of the apparatus shall be proportionate to the square of the movement of the
collar reckoned from the point of suspension. An exact application of this
principle requires that the two arms shall be suspended from the same point
of the spindle, that the collar shall be suspended from a single point, and that
the connecting arms which carry it shall form with the weighted arms a
perfect or equilateral four-sided figure. These conditions having been ob-
served, the only other requisite condition is the employment or intervention of
a counterbalanced weight, which shall exert on the collar a pressure increasing
uniformly with the height of the collar reckoned from a point selected ad
libitum on the axis of rotation.
The following arrangements may be employed, as the case may be.
Figure 1. The governor having its arms inclined at an angle of 45°, a
point B.is taken at the height of the groove of the collar, and made the
centre of motion of a right-angled lever, one of the arms of which has its
end C engaged in the groove of the collar, and the other arm carries a
counterbalance weight, which, as the governor moves, is inclined to the
one side or the other, and exerts on the collar or ring a pressure varying
uniformly with the height reckoned from the level of B.
Figure 2. By bringing the point B into the plane of the spindle, and
taking a second fixed point F, then with the bent lever and with the rods A, F,
and A, C, a jointed arrangement will be composed, which will accompany the
collar in a right line, and will occupy less space while exerting like action on
the collar.
Figure 3. But if the amount of space permit it, it is preferable to place
the counterbalance weight on the bent or angle lever A Fμ, for thereby much
greater precision is attained, B and F remain fixed points, and the bar A, C,
is obliged to accompany the collar in a right line, and communicate to it
whatever its position a variable pressure adapted to isochronism.
SPRING GOVERNOR OR REGULATOR.
Figure 4. Suppose that in the governor formed with an equilateral
quadrilateral, that is, where the weighted arms and the connecting arms form
an equilateral four-sided figure, the point of suspension be put in the place of
the collar, and the collar in the place of the point of suspension, the balls as
they are thrown out more or less will be retained in the plane of suspension
B, S, B', and in a state of rest, the apparatus will be in equilibrium whatever
the direction of its axis, and however far the balls be thrown out. Let there

page_text: then be fixed on the spindle a bar which shall turn with it, and to which bar
shall be attached springs, Figure 5, which by their other end shall act on the
balls; a governor will thus be formed, in which at the ordinary regular working
speed the springs will be in equilibrium with the centrifugal force. If, more-
the springs are regulated so that their elongation shall be equal to the
divergence or separation of the balls, perfect isochronism is obtained, because
for a like speed of rotation and for different extents of revolution or divergence,
that is, throw of the balls, the elasticity of the springs and the centrifugal
force of the masses vary in the same ratio.
over,
In this combination isochronism will depend also on the condition that the
work of the springs shall be proportionate to the square of the movement of
the collar taken from the point of suspension S.
The simplicity of its construction, its property of isochronism, and its
freedom from being affected by variations of gravity, render this governor very
suitable for use on board ship.
COMBINED GOVERNOR.
Figures 6 and 7.-Springs may also be used to replace the action of the
compensation counterbalance weight. The bar A, C, which embraces the
collar by its bifurcated end C, is obliged to follow the direction of the spindle,
and consequently the other end A moves in the direction A, B. If then
springs be extended between A and B, the force of traction exerted at A will
be transmitted vertically to C, according to the progression necessary for pro-
ducing isochronism. Here again the total work of the weights and springs is
proportionate to the square of the movement or travel of the collar from the
point of suspension S.
Figure 8. In all those governors in which the equilateral quadrilateral is
an essential and indispensable feature of construction, the segmental guides
hitherto used are not required, by reason of the method adopted for suspending
the arms, which are broadly forked, and are jointed together on a cross axis
in a piece with or fixed to the spindle.