Improvements in and relating to Nozzles for Water Motors.
Year: 1899

page_text: Compinda C
Date of Application, 18th Feb., 1899
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PROVISIONAL SPECIFICATION.
Improvements in and relating to Nozzles for Water Motors.
We, SAMUEL CLELAND DAVIDSON, of Sirocco Engineering Works, Belfast,
Ireland, Merchant, and ALEXANDER BASIL WILSON, of Holywood, County Down,
Ireland, Engineer, do hereby declare the nature of this invention to be as
follows:-
-
Our invention has reference to the nozzles employed for directing the stream of
water or other fluid on to the buckets or plates of revolving wheels or water
motors hereinafter referred to as "wheels" and its chief object is to vary the
effective orifice of efflux of the nozzles.
An important feature of the invention is an elastic nozzle connected with a
compressible vessel, the effective orifice of the nozzle being more or less con-
tracted according to the greater or less compression of the said vessel and the
amount of the compression being determined by the position of the governor
balls or by other governing device actuated according to the speed of the wheel
or by other means.
Our invention may be carried into effect as follows:-
We make the nozzle proper of flexible or elastic material such for example
as vulcanised india rubber and we surround it with a casing leaving a space
hereinafter called the "chamber" between them; this chamber is connected to
a compressible vessel by a pipe or equivalent connection. We fill the chamber,
the compressible vessel and the connecting pipe with an incompressible liquid.
preferably water. We connect a governor actuated according to the speed of
the wheel (which governor may be of any suitable construction) with a pressing
device in contact with the compressible vessel in such manner that when the
governor balls fly out from increase of speed the said vessel is compressed, the
amount of compression depending upon the distance the balls have moved out-
wards. The compression of the vessel forces its contained liquid into the
chamber so that the wall of the nozzle proper is forced inwards and the effective
orifice is thereby proportionately reduced. When owing to decrease in the speed
of the wheel the governor balls again move inwards the compressible vessel
expands and the effective orifice of the nozzle proportionately increases. Since the
pressure of the liquid within the nozzle on its way to the wheel acting on the
flexible wall of the nozzle will tend to expand the compressible vessel we employ
a weight or equivalent device to balance such tendency and thereby relieve the
governor of the power required to compress the receptacle against such pressure.
The weight or other device is regulated according to the pressure of the liquid
within the nozzle on its way to the wheel. The governor has therefore only to
vary the respective volumes of the vessel and the chamber around the nozzle
according to its speed of rotation and consequent position of the balls.
The arrangement above described is sufficient to govern the speed of the wheel
when working against varying loads. In order to govern the speed not only
under varying loads but with varying fluid pressure supplied for its driving we
so arrange the weight above described, that it is in effect increased as the pressure

page_text: of water supplied to the motor rises. This increase we may obtain for example
by means of a ram working in a cylinder connected to the supply of fluid, the
ram bearing downwards on the weight, or a device of an equivalent kind whereby
the increased pressure of the fluid is in effect added to the weight.
Another convenient way of adding the increase of water pressure to the said
weight is to connect a short tube of vulcanised rubber or similar material to the
fluid supply. One end of this tube is stopped, and is so connected to the weight
or its equivalent that when there is only normal pressure in the fluid the tube is
bent and the weight is not acted on thereby; as the pressure of fluid increases,
and the pressure within the aforesaid tube in consequence rises, the tube
gradually straightens. The variation in its straightness due to the variation in
the pressure of the fluid within it is utilised to add to the effective weight, and
thereby correspondingly increase the pressure within the compressible vessel.
The compressible vessel may be conveniently constructed of a hollow ball of
vulcanised rubber, permanently compressed by the weight and by the ram or
its equivalent, such permanent compression corresponding to the pressure of
the fluid flowing to the nozzle, and with an additional varying compression
produced by the varying position of the governor balls as herein before described.
The nozzle is of suitable conical shape internally to produce the approximately
correct acceleration of the fluid from the larger to the smaller end. The sub-
stance of which the nozzle is made is preferably of gradually decreasing thickness
from its larger opening to its smaller opening or outlet. The surrounding
casing may be made wholly or partly of vulcanised rubber or similar substance
or wholly or partly of metal or other inelastic material. If made wholly or
partly of rubber it should have a cover of metal or other rigid material to
prevent it expanding outwards.
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J. C. MEWBURN & ELLIS,
55 and 56, Chancery Lane, London,
Chartered Patent Agents.
We, SAMUEL CLELAND DAVIDSON, of Sirocco Engineering Works, Belfast,
Ireland, Merchant, and ALEXANDER BASIL WILSON, of Holywood, County Down,
Ireland, 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:-
Our invention has reference to the nozzles employed for directing the stream of
water or other fluid on to the buckets or plates of revolving wheels or water
motors and its chief object is to vary the effective orifice of efflux of the nozzles.
An important feature of the invention is an elastic or flexible nozzle sur-
rounded by a chamber which is in communication with a compressible vessel,
the effective orifice of the nozzle being more or less contracted according to the
greater or less compression of the said vessel and the amount of the compression
being determined by the position of the governor balls or by other governing
device actuated according to the speed of the wheel or by other means.
The accompanying drawing represents a sectional elevation of a construction
of apparatus embodying our invention.
1 is the casing of the water motor driven by the water jet issuing from the
nozzle 2 which is supplied by the supply pipe 24. The nozzle 2 is made of india

page_text: rubber or other suitable elastic water-tight material and it is surrounded
peripherally by a space or chamber 3 enclosed within a casing 4 which is made
in one piece with the nozzle 2 with the object of avoiding a complicated joint
at the tip of the nozzle. 5 is an outer cover of metal to prevent the casing 4
from expanding outwards. The chamber 3 is connected by a passage 6 with a
pipe leading to one end of a cylinder 8 fitted with a piston 9.
7
Between the
admission end of the cylinder and the piston there is arranged a compressible
vessel or bellows-like bag 10 of water-tight flexible material into which the
pipe 7 opens direct. The chamber 3, passage 6, pipe and vessel 10 are filled
with water or other practically incompressible liquid, sufficient space being left
between the walls of the cylinder 8 and the vessel 10 to allow of the latter
expanding as hereinafter described. The rod 11 of the piston 9 is provided at
its opposite end with a piston 12 working in a cylinder 13 which is fitted with
a compressible vessel or bag 14 similar to the one in the cylinder S. From the
vessel 14 a pipe 15 leads to the water supply pipe 2. A suitable bracket 16
fixed to the water motor casing carries in bearings a stud 17 on which is pivoted
a lever 18, 19. The arm 18 of this lever is coupled at an intermediate point of
its length by means of a pin and slot connection 20 to the centre of the piston
red 11. An adjustable spring 21 carried by an arm projecting from the cylinder 8
is arranged to engage the arm 18 of the lever with varying leverage on the latter
as shown. One end of the motor shaft 22 projecting from the motor casing
carries a water-tight ball 23 of indiarubber containing a small quantity of
water to give weight. This ball is fixed at its opposite end to a sleeve 24 adapted
to slide on a guide spindle 25 forming part of the shaft 22. Into the outer end
of the sleeve 24 is screwed a pointed piece or centre 26 arranged to bear against
the outer end of the arm 19 of the lever 18, 19.
The ball 23 revolving with the motor shaft constitutes a centrifugal governing
device. The outline form of the ball when at rest is as indicated by the dash-
dotted line 2.
At the mean speed of the motor the ball will be expanded by centrifugal
action and will assume the shape shown in full lines 23. At a higher speed
the ball will assume the form indicated by the dotted line y. This change of
outline or conformation of the ball along its horizontal axis produces a sliding
movement of the sleeve 24 in or out along the spindle 25, with a corresponding
movement of the lever 18, 19 in the direction of the arrows a and b respectively.
The deformation of the ball 23 to the outline y by increase of speed, permits
the lever 18, 19 to be moved by the spring 21 in the direction of the arrow a. On
a decrease in speed the elasticity of the ball 23 acting with a tendency to return
to the shape indicated by the line pushes the lever 18, 19 in the direction of
the arrow in opposition to the spring 21.
The vessel 14 being connected by pipe 15 to the supply of fluid in the pipe 2
and the vessel 10 being connected by pipe 7 to the nozzle chamber 3; and the
vessels 14 and 10 being connected so far as regards their expansion and con-
traction by pistons 9 and 12 and united by rod 11. The pressure of the fluid
in 3 is the same normally as in the pipe 2. If however the vessel 10 is com-
pressed by the action of the governor through lever 18, 19 the chamber 3 will
be increased in volume and the flow through the nozzle thereby restricted.
The spring 21 is used as a means of adjustment to maintain the shape and area
of the nozzle which is requisite in order to maintain the desired normal speed
of the motor.
The speed of the wheel when working against varying loads is regulated by
the action of the ball 23. An increase in the speed of the wheel causes the
tall to become shortened in the direction of the centre 26, and thus allow the
spring 21 to pull the arm 18 of the lever 18, 19 which moves on its pivot 17 so
as to push the piston rod 11 and the piston 9 with the result of compressing the
vessel 10 and consequently of forcing water into the chamber 3 whereby the
volume in said chamber is increased. This increase of volume forces the wall

page_text: of the nozzle 2 inwards and its effective orifice is thereby proportionately
reduced with the result of correspondingly correcting the speed of the motor.
When the ball 23 becomes elongated in the direction of the centre 26, as a
consequence of a reduction in the speed of the motor. The lever 18, 19 is moved
so as to increase the volume of vessel 10 by the action of piston 9 and thereby
decrease the volume of the nozzle chamber 3, with the result of allowing the
nozzle to expand and increase its effective area with a corresponding increase
in the speed of the motor.
Any variation of pressure of the liquid in the supply pipe 2ª and within the
nozzle 2 is transmitted through the pipe 15 to the cylinder 13 and thence
through the pistons 12 and 9, compressible vessel 10, and pipe 7 to the chamber 3,
and consequently the apparatus governs the speed only under varying loads
but also under varying fluid pressure. The two compressible vessels 10 and 14
connected respectively with the chanber 3 and the source of fluid supply in
fact constit te with their pistons 9 and 12 a sort of relay by means of which the
effective orifice of the nozzle is regulated according to the speed of the motor
and the pressure of the fluid supply. The two pistons 9 and 12 may be said to
act as a diaphragm in a fluid chamber consisting of the two vessels 10 and 14.
The centrifugal ball 23 is not an essential part of our apparatus as it is
obvious other arrangements for operating upon the vessel 10 through
the action of a governor can be employed which will cause the
lever 18, 19 to move in the direction of arrow a on increase of speed, and in the
direction of arrow 6 on decrease of speed. It will be observed that there is no
flow of liquid through the chamber 3 or through any of the parts in com-
munication therewith; there is therefore no liability of the action of the
apparatus being affected by particles of grit or other matter.
Having now particularly described and ascertained the nature of our said
invention and in what manner the same is to be performed, we declare that
what we claim in respect of nozzles for water motors is:-
1. An elastic or flexible nozzle surrounded by a chamber which is in com-
munication with a compressible vessel, the said chamber, compressible vessel
and their communication being filled with liquid which cannot escape therefrom
and the said vessel being more or less compressed according to the position
of governor balls or other governing device whereby the volume of fluid in the
said chamber is varied and therefore the effective orifice of the nozzle auto-
matically regulated according to the speed of the motor, substantially as herein-
before described.
2. The employment of two compressible vessels one of which is in communica-
tion with a chamber surrounding an elastic or flexible nozzle and the other in
communication with the source of fluid supply to the nozzle, the said com-
pressible vessels being so arranged in relation to each other and to the governor
that the rise and fall of the governor balls will simultaneously compress one
of said vessels and allow the other to expand whereby the volume of fluid within
the chamber surrounding the nozzle is altered and the effective orifice of the
nozzle automatically regulated, substantially as herein before described.
3. The combination of parts constituting apparatus for automatically regulat-
ing the effective orifice of nozzles for water motors, substantially as described
and shown.
Dated this 20th day of November 1899.
J. C. MEWBURN & ELLIS,
55 and 56, Chancery Lane, London,
Chartered Patent Agents.