or other Elastic Fluid.
Year: 1886

page_text: or other Elastic Fluid.
I, HENRY DAVEY, of Rupert Lodge, Headingley, near Leeds, in the County of
York, Engineer do hereby declare the nature of this invention and in what
manner the same is to be performed to be particularly described and ascertained
in and by the following statement:―
My invention relates to a construction and arrangement of governor in con-
junction with an expansion valve in such a manner that, according as the speed of
the governor is greater or less, the expansion valve cuts off supply of working fluid
to an engine at an earlier or later period of the stroke, as I will describe referring
to the accompanying drawings.
Fig. 1 is a vertical section of the governor and expansion valve, Fig. 2 is a
transverse section on X X, Fig. 3 is a sectional plan on Y Y and Fig. 4 is a sectional
plan on Z Z.
A is a slide case having an induction passage I and an eduction passage E,
conducting steam or other elastic fluid to and from a cylinder C by a port P
governed by a partially rotating cylindrical slide valve B. In front of a passage F
leading into the casing of the valve B, I mount the rotating semi cylindrical
expansion valve V which is worked in the following manner.
The governor
spindle G which is caused to revolve by the engine, one revolution for each
revolution of the engine shaft, has fitting freely upon it a sleeve S on which is fixed
a mitre pinion D gearing with a mitre pinion H fixed on the spindle of the valve V.
The sleeve S has also fixed upon it a casing L in which are pivotted two segmental
weights W gearing with a pinion K which is fixed on the spindle G. The upper
part of the casing L contains a volute spring T, one end of which is fixed to the
casing and the other to the boss of the pinion K. As the spindle G and pinion K
revolve, the rotation communicated through the spring T causes also the casing L,
the sleeve S, the mitre pinions D and H and the valve V to revolve, the valve V
in every revolution opening and closing the port F. But, while the casing L
revolves carrying round with it the weights W, these tend by centrifugal force to
move outwards and being engaged with the pinion K they have the effect of
turning the casing L farther round and through it the sleeve S and the valve V.
The position of the valve V relatively to the spring T is in the first place adjusted

page_text: so that when the engine and governor revolve at moderate or normal speed, the
weights W being then in the position shown in Fig. 3, the valve V in revolving
cuts off supply at a late period of the stroke. But, when the engine and governor
revolve more rapidly, the weights W moving outwards cause the valve V to be
partly turned in a forward direction so as to cut off supply at an earlier period of
the stroke.
Although I have shewn the expansion valve V as governing supply to a partly
rotating slide valve B, obviously it could be applied to slide valves of other kinds.
For a double acting engine the valve V should rotate at double the speed of the
crank shaft, so as to give two supplies for each revolution of the engine. Instead
of mitre gear D, H, bevil gear might be used, so proportioned that whatever the
speed of the governor relatively to that of the engine shaft, the valve V should
nevertheless have its proper speed.
Having now particularly described and ascertained the nature of the said
invention and in what manner the same is to be performed, I declare that what
I claim is :-
14
In combination with a governor spindle driving through a spring a rotating
expansion valve and a casing containing pivotted segmental weights, a pinion on
the spindle gearing with the weights, in such manner that outward movement of
the weights due to centrifugal force causes the valve to advance relatively to the
spindle, so as to cut off supply at an earlier period, substantially as described.
ABEL & IMRAY,
Agents for the Applicant.