Improvements in and connected with Milking Machines.
Year: 1896

page_text: Date of Application, 2nd May, 1896
Complete Specification Left, 5th Oct., 1896-Accepted, 7th Nov., 1896-
PROVISIONAL
SPECIFICATION.
Improvements in and connected with Milking Machines.
I, ALEXANDER SHIELS of 190 Bath Street, Glasgow, M.B., C.M., B.Sc., do
bereby declare the nature of this invention to be as follows:-
This invention relates to vacuum milking machines and it has for its object to
improve and simplify their construction.
In my present invention, I supply vacuum, from any suitable or available source
of supply, at a constant power of suction to one or more pipes which pass round
the byre or other place in which the cows are to be milked and to any one of a
series of cocks fitted on the pipe or pipes I connect a small vacuum regulating and
controlling machine of special construction.
The invention is a further development and improvement upon my prior Patents
Nos. 8325, 14638, 6997, for milking machinery.
In carrying out my present invention I fit, in any suitable situation within the
byre, one or more pipes having cock connections on them one for each stall or pair
of stalls. The pipe or pipes are connected by another pipe, provided with an
automatic valve for regulating the supply of vacuum, to the source of vacuum
supply. The valve is so arranged as to give vacuum to the byre pipes at a constant
power of suction.
The machine, which will be hereinafter more fully described, for regulating and
controlling the vacuum supply to the teat cups is arranged to be coupled in any
well known manner, on the one band with any one of the cocks of the byre pipes
and on the other hand with a milk pail and teat cups.
The machine for regulating and controlling the vacuum consists of a vacuum
motor constructel with two cylinders whose pistons work an oscillating cross head or
shaft provided with a, preferably, sectoral cam at each end. One cam reciprocates
a lever attached to the spindle of a pulsating valve whilst the other cam
reciprocates a lever for opening, and closing an air admission valve used in
conjunction with a vacuum destroying valve. The pulsating valve and the vacuum
destroying valve are connected together and to the pipe leading to the teat cups
by means of a suitable pipe connection.
The vacuum supply from the byre pipes is led direct to the pulsating valve and
a branch pipe, provided with a suitable regulating cock, supplies vacuum to the
controlling valve of the cylinders of the motor. This controlling valve is preferably
made in the form of a balanced double piston which is moved back and forward so
as to open and close alternately the ports leading to and from. each cylinder by
means of a double arm "knocker" or escapement lever arrangement which is
actuated from or by the oscillating cross head or shaft. This "knocker" strikes
the spindle or an arm or plate on the spindle and, at the proper times, shifts the
valve so as to place the ports leading from the cylinders either in communication
with the atmosphere or the vacuum supply.
The cams are so shaped as to give the proper movement to the levers actuating
the pulsator and air admission valves.
The pulsator, vacuum destroying, and air admission valves are preferably of the
same construction as those described in the Specifications of my prior Patents
Nos. 14638, and 6997 aforesaid.
The cock used for regulating the vacuum supply to the controlling valve of the
cylinders is by preference made in the form of a screw which works in a tapped
casting fitted on the vacuum supply pipe.

page_text: With this apparatus when it is desired to milk a cow all that is necessary is to
fit the vacuum controlling and regulating mechanism with its milk pail and teat
cups in connection with one of the cocks of the byre pipes and then fit the teat
cups on the cow's teats.
The vacuum controlling and regulating mechanism is made very small and is
preferably enclosed within a neat box or casing.
If desired a "by-pass" valve for automatically supplying, when necessary,
additional vacuum to the teat cups, may be used with the apparatus.
In some cases the byre pipes and cocks may be dispensed with and the
vacuum regulating and controlling mechanism connected direct to the source of
supply.
Dated this 1st day of May 1896.
H. D. FITZPATRICK,
70 Wellington Street, Glasgow, Agent.
I, ALEXANDER SHIELS of 190 Bath. Street, Glasgow, M. B., C.M., B.Sc., 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:
This invention relates to vacuum milking machines and it has for its object to
improve and simplify their construction.
In my present invention which is an improvement upon the "Shiels" milking
machine supply vacuum from any suitable or available source of supply, at a
constant power of suction, to one or more pipes which pass round the byre or
other place in which the cows are to be milked; and, to any one of a series of
cocks fitted on the pipe or pipes, I connect a small vacuum regulating and
controlling machine of special construction.
The invention is a further development of and improvement upon my prior
Patents Nos. 8325° 14638, 6997 for milking machinery.
And in order that my said invention may be properly understood I have hereunto
appended 6 explanatory sheets of drawings, whereon,
Fig. 1 is a side elevation of the machine as it appears fitted in its enclosing
casing.
Fig. 2 is a plan of the machine.
Fig. 3 is an end view of the machine.
Fig. 4 is a sectional view of the valve 34, 35.
Fig. 5 is a plan of the valve 34, 35.
Fig. 6 shows enlarged views of the cams 18, 19.
Fig. 7 is a side view, Fig. 8 a section and Fig. 9 a front view of the pulsator
valve 26 and the vacuum destroying valve 29.
Figs. 10 and 11 are sectional views, taken at right angles to each other, of the
motor cylinders with their pistons.
Fig. 12 is a section, Fig. 13 an end view, Fig. 14 a plan and Fig. 15 a front
view of the pulsator valve 26.
In carrying out my present invention I fit, in any suitable situation within the
byre, one or more pipes having cock connections on them, one for each stall or pair
of stalls. The pipe or pipes are connected by another branch pipe, provided with
an automatic valve of any well known and suitable constructio for regulating the
supply of vacuum, to the source of vacuum supply. This valve is so arranged as
to give vacuum to the byre pipes at a constant power of suction.
The machine for regulating and controlling the vacuum supply to the teat cups

page_text: 18 arranged to be coupled in any well known manner, on the one hand, with any
one of the cocks of the byre pipes, and, on the other hand, with a milk pail and
teat cups.
The machine consists of a vacuum motor constructed with two cylinders 1, 2,
(as shown at Figs. 1, 2, 3, 5, 10 and 11), consisting of cylindrical pieces inserted
into cast bottoms 3 provided with screwed downward extensions 4 whereby they
can be bolted to the bed plate 16. Fitted in each cylinder is a solid piston 6
provided with a ring cup leather 7 and with a cylindrical upward extension 8 to a
pin 9 inserted in which the lower end of the connecting rod 10 is secured. 17 are
guide arms made one with the extension 8.
The upper ends of the connecting rods 10 are pinned to two crank arms 11, 12,
fixed to an oscillating shaft 13, carried in bearings at the top of small pillars 14, 15,
secured to the bed plate 16 of the machine. This shaft 13 is provided with some-
what sectoral shaped cams 18, 19, one at each end, as shown. The cam 19 is
capable of depressing the free end of a lever 20, fulcrumed on the pillar 21, thereby
raising its other end and opening an air admission valve 22 enclosed in a casing 23
(see also Figs. 7, 8 and 9). The other cam 18 operates, in a similar manner, a
lever 24 fulcrumed on a pillar 25 (see also Figs. 12 to 15) and opens a pulsating
valve 26 enclosed in a casing 27.
The air admission valve casing 23 is, as shown at Figs. 7 to 9, connected with
the casing 28 of a vacuum destroying valve 29.
The constructions of these different valves and their accessory parts will be more
fully described hereafter.
The casings 27 and 28 of the pulsating valve and the vacuum destroying valve
are connected together as shown at Fig. 1 and 7 by a Y coupling 30 to which a
rubber or other pipe 31 leading to the teat cups of the milking machine is
attached.
The vacuum supply from the byre pipes is carried by a pipe connection 31 direct
to the branch 32 of the pulsating valve casing 27.
A small pipe 33 (Fig. 2) supplies vacuum from the branch 32 to the controlling
valve for regulating the supply of vacuum to the cylinders of the motor. This
valve, preferably, consists of two cup leather pistons 34, 35, (see Figs. 4 and 5)
fitted on a spindle 36 and enclosed in a tubular casing 37 secured within the
casting 38. The ends of the casing are slotted on the upper side as shown at 39
and 40. A forked lever 44 at the outside of the casing 37 has its downwardly
projecting ends 45, 46, passed right through the slots 39, 40, and attached to sliding
discs 41, 42, in the casing. A tooth 47 is made at the centre of the forked lever.
The dotted lines 50, 51, (Fig. 5) show the ports leading from the valve casing to
the cylinders and the dotted circle 52 Fig. 4 indicates the supply port leading
from the pipe 33.
53 is a small screw down valve for opening or closing the branch pipe 33.
A small jaw 48 is cast in one with the casting 38 and upon this jaw is mounted
a kicker having two arms 54, 55, which are capable of striking the tooth 47 of the
fork lever. Made one with this kicker is a short arm 56 which is jointed to a
slotted link 57 pinned at its upper end to a crank arm 58 on the shaft 13; and also
a long arm 59 having attached to its upper end a spring 60 which is secured to an
eye-pin 61 inserted in the bed plate 16.1
The pulsator valve as shown at Figs. 12, 13, 14 and 15 is of very simple
construction merely consisting of the casing 27 with a web 62 cast therein which
web is bored with a hole 63 and is provided with a ring seat 64 for the valve 26.
A three armed guide nut 65 is screwed on the lower end of the spindle of the
valve. At the upper end of the spindle of the valve is a piston 66 having a
convex upper surface and a diaphragm 67 held in place by a screw cap 68. Air
is admitted through a hole 68 in the cap 68 to the top of the diaphragm. The
piston 66 serves as a guide and also as a support for the diaphragm. The upper
end of the spindle of the valve is attached by a link 69 to the lever 24 which latter
bas a tooth 24 at its end. As the area of the diaphragm 67 is greater than that

page_text: of the valve 26 it follows that the valve 26 will normally be held closed by the
action of the atmosphere on the diaphragm 67. 70 is a branch leading to the
Y coupling 30.
The vacuum destroying valve 29 shown in Figs. 7, 8 and 9 is also of a simple
construction. It is similar to the pulsator valve except that instead of closing
down on its seat it closes up against a ring seat 71 made on the web 72 of the
casing 28. 73 is a guide nut similar to the one 65 Fig. 12. The valve spindle 74
is screwed and has on it a guide and supporting piston 75 and a diaphragm 76 open
to atmospheric pressure on its upper side. The spindle is extended out through
the easing cover 77 and has fitted on its upper end an adjustable cap 78 which is
capable of being screwed up and down on the spindle so as to regulate the tension
of the spring 79. 80 is the branch leading to the coupling Y pipe 30. The
snction in the pipe 30 acts on the valve 29 and in conjunction with the action of
the air on the diaphragm 76 tends to open it, but the spring 79 is so adjusted by
the cup 78 that the valve only remains open so long as the vacuum in the pipe 30
exceeds a certain desired minimum degree.
The air admission valve 22 is normally held closed against its seat 81 by means
of the spiral spring 82 held in place between the back of the valve and the cover 83
of the casing 23. 8+ are air holes made in the casing. The spindle of this valve
is connected by a link 85 to the end of the lever 20 which is also provided with a
tooth 20ª.
The valves 29 and 22 work in conjunction as hereinafter described.
The action of the apparatus is as follows:-The small machine is first connected
by the pipe 31 to the cock on the vacuum supply pipe and by the pipe 31" to the
milk pail and teat cups as usual. Then the small screw down valve 53 (Fig. 5) is
opened and a supply of vacuum admitted from the pipe 33 through the port 52 to
the valve casing 37. Now, presuming that the piston of No. 2 cylinder is in the
up position and the piston of No. 1 in the down. position (i.e. the reverse of what is
shown on the drawings) the piston valve 34, 35, would be in a position to supply
vacuum from the pipe 33 and port 52 to the cylinder 2. The vacuum acting on
the underside of the piston sucks it down and at the same time oscillates the
shaft 13 thereby causing the cam 18 to deprèss the tooth 24 on the end of the
lever 24 thereby pulling up the valve 26 against the action of the air on
the diaphragm 67 and supplying vacuum to the pipe 30, 31, and the teat cups.
The oscillation of the shaft 13, however at the same time causes the link 57 to be
gradually depressed and after moving a short distance, represented by the length
of the slot at its lower end, to act on the arm 56 and cause the kicker arm 55 to
strike against the tooth 47 of the fork lèver 44 and knock that lever and the valve
spindle 36 with its valves 34, 35 over to the position shown on the drawings at
Figs. 4 and 5, ie, to the position for supplying vacuum from the port 52 to the
port 50 and cylinder 1 and for admitting air from the end of the casing 37 through
the port 51 to destroy any vacuum in the cylinder 2.
The valves 34, 35, being in the position shown at Figs. 4 and 5 and the piston of
cylinder 1 being now in the up position as shown in dotted lines at Fig. 3 the
vacuum from the port 50 acting on the underside of the piston sucks it down and
causes it, as a consequence, to oscillate the shaft 13 in an opposite direction to the
previous oscillation thereby causing the cam 18 to gradually release the tooth 24
and permit the pulsator valve 26 to close down on its seat under the action of the
air pressure on its diaphragm 67. Just after the valve 26 has closed the cam 19 is,
by the continued oscillation of the shaft 13, caused to gradually depress the
tooth 20 of the lever 20 thereby opening the air admission valve 22 and admitting
air to the valve 29, which, shonld there be more than the desired minimum of vacuum
in the pipe 30 will be open, so that air at once rushes in and destroys the vacuum
in the pipe 30 until it is reduced down to the desired minimum limit when the
valve 29 will antomatically close by the action of the spring 79.
This reverse oscillation of the shaft 13 causes the link 57 to again pull up, after
a certain time, the arm 56 and to eventually cause the striker 54 to strike the

page_text: tooth 47 of the fork 44 and knock back the valve 34, 35, to its original position,
i.e. to a position to again supply vacuum to the cylinder 2 and to admit air through.
the slot 39 to destroy the vacuum in cylinder 1.
A sudden knock each time is given to the fork 44 by the action of the spring 60.
Whenever the long arm 59 of the kicker passes the centre of the pillow 14, on-
either one side or other, which will only be when the striking arms are near the
tooth 47, the spring 60 exerts its force suddenly and gives a rapid movement to
the kicker and causes the latter to strike the tooth 47 with sufficient force to drive
the valve 34, 35 to one side or other of its casing.
The length of the slot in the link 57 is so arranged that the piston which is for
the time being desceuding always has sufficient stroke to be effective before the
valve 34, 35, is shifted.
The cams 18, 19 are of a peculiar shape, as shown at Fig. 6. The cam 18.
tapers from the point a to the point 6 from which point to the point c it is arced.
This formation of the cam ensures that the tooth 24" and lever 24 will be gradually
depressed whilst the cam is travelling from the point a to the point b and to be
held depressed whilst the cam is travelling from 6 to c. This peculiar action
causes the pulsator valve 26 to gradually open and then to remain fully open for a
short time equal to the period taken by the cam in travelling from 6 to c. At the
reverse oscillation of the shaft 13 the action is reversed and the pulsator is kept
fully open during the time the cam is travelling back from c to b and then to
gradually close during the period taken to travel from b to a.
The cam 19 is of a similar shape except that the incline from a' to 6' is sharper..
This cam causes the air admission valve to be opened rapidly and then retained
open for a short time, thereafter, at the reverse oscillation, to remain open for a.
short time and then rapidly close.
The one cam only comes into action just after the other one has ceased to act,.
so that the air admission valve 22 is only opened when the pulsator valve is
closed.
If desired, an adjustable spring 100 shown dotted in Fig. 15 can be attached to
the lever 24 so as to open the valve 26 should the vacuum in the pipe connection 70-
fall below the desired minimum thus acting for the time being as a "by-pass.
valve." This spring 100 is attached at its lower end to a sleeve 101 fitted loosely
on a screw stud 102. The tension of the spring can be regulated by means of a
screw nut 103.
If desired a cam surface or curve may be cut on the ends of the levers 20, 24,
and a projection or point be made on the oscillating shaft or its cranks instead of
using the cams 18, 19, and the projections 20" & 24" on the levers.
The structural details of the invention can be modified or altered without
departing from the principle of the invention.
Having now particularly described and ascertained the nature of my said inven--
tion and in what manner the same is to be performed, I declare that what I
consider novel and desire to claim is :-
1. The general arrangement and combination of parts of the apparatus for
regulating and controlling vacuum substantially as hereinbefore described and
shown on the drawings aunexed.
2. The vacuum motor mechanism for operating the pulsating and air admission
valves constructed, arranged, and operating, substantially as herein before described.
with reference to the drawings annexed.
Dated this 2nd day of October 1806
H. D. FITZPATRICK,
70 Wellington Street, Glasgow, Agent..