Improvements in Hydraulic Machines for Automatically Regulating- the Supply and Return of the Power Water.
Year: 1892

page_text: Date of Application, 15th June, 1892-Accepted, 23rd July, 1892
COMPLETE SPECIFICATION.
Improvements in Hydraulic Machines for Automatically Regulating-
the Supply and Return of the Power Water.
1, GEORGE SMITH DUNCAN of Melbourne Chambers, Little Collins Street,.
Melbourne in the Colony of Victoria, Civil 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:-
In my Specification No. 20515 of 1890 I described arrangements of hydraulic
machines whereby the amount of water employed for working is proportioned to
the load to be overcome. As part of a machine so arranged I described a governing
valve mechanism such as is shown by Figs. 5, 6 and 7 on Sheet 3 of the drawings
annexed to the said Specification, by which communication, under certain conditions
of load and pressure, was effected between two hydraulic cylinders.
My present invention consists in an improved construction of the governing
valve, of the the automatic charging and discharging valve and of mechanism for
working these valves, as I shall describe referring to the accompanying drawings.
Fig. 1 is a vertical section of the governing valve and mechanism for working it.
Fig. 2 is a vertical section of the automatic charging and discharging valve with
side elevation of the spring tappets for working it.
Referring first to Fig. 1, H is the small hydraulic governing cylinder com-
municating with the main cylinder by the pipe . The plunger of H is held down
by an adjustable spring until the pressure communicated by * is sufficient to
overcome the force of the spring, whereupon the plunger rises and moves the lever
arm to which it is connected by the link 3. The other arm of the lever
being thus caused to move in a circular are along the face of a lever arm A depresses
that arm, and raises the other arm B which being loaded would otherwise hold
down the plunger C to which is attached a sliding pin D.
When the plunger C is held down this pin obstructs a passage from the pipe E.
which leads to one of the hydraulic cylinders. While this passage is obstructed
the space above the piston F being charged from the high pressure main K through
a small hole in the valve G the pressure on the piston keeps the valve closed, but
when the passage is unobstructed, the pressure above the piston F is released and
the valve G opens admitting water under pressure to the pipe E.
The end of the lever arm A is sloped off so that if the arm 9* should pass.
beyond it, even when A is raised by the counterweight, the arm g* can return to
its position above A. In order to avoid shocks an arm is linked to a dashpot go.
charged with oil.
Referring now to Fig. 2, a stop L projecting from the main plunger, when, owing-
to leakage, that plunger ascends or descends too far, it meets one or other of the
spring tappets M', M, and thereby raises or lowers the sliding rod N from which
projects a stud engaging the fork of a lever O. This lever moves a tubular
plunger P through one side of which there are two holes pp', the one p being-
brought to face the lateral pipe Q when the plunger P is raised, and the other pl
also to face the pipe Q when the plunger P is lowered. Thus at each end of the
stroke of the main plunger, if that stroke is carried too far there is communica-
tion between the pipes and R, but when the main plunger does not make its
stroke too far, the plunger P remains about midway, the communication being
closed.
The pipe Q communicates with the pipe K of the valve shewn in Fig. 1, the-
pipe R communicates with the lower end of the lowest main bydraulic cylinder.

page_text: Having now particularly described and ascertained the nature of this inven
tion and in what manner the same is to be performed, I declare that what I
claim is :-
1. The governing valve mechanism, substantially as described with reference to
Fig. 1.
2. The automatic charging and discharging valve, substantially as described
with reference to Fig. 2.
Dated this 15th day of Tue 1800
ABEL & IMRAY,
Agents for the Applicant.