Improved Method of and Apparatus for Producing Pulsation in the Teat-cups of Milking Machines.
Year: 1897

page_text: Date of Application, 12th Aug., 1897-Accepted, 25th Sept., 1897
COMPLETE SIMCITICATION,
Improved Method of and Apparatus for Producing Pulsation in the
Teat-cups of Milking Machines.
I, HERBERT JAMES CUNNINGTON, of 71 Cathedral Square, Christchurch, in the
Provincial District of Canterbury, in the Colony of New Zealand, Engineer,
do hereby declare the nature of my 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 the class of milking machines in which vacuum or partial
vacuum is employed to cause milk to flow from the teats of the animal.
The use in such machines of a teat cup having an inner flexible lining caused
to "pulsate," that is, to alternately contract and expand upon the teat, is well
known.
The object of the pulsation is to imitate as nearly as possible the natural action of
the mouth of a calf, or the action of a person's hand when milking; and it has been
obtained in various ways, one of which consists in using a special air pump to
alternately force air into, and withdraw air from; the annular space between the
flexible inner lining and the rigid outer wall of the teat cup.
I have found by experiment that, in milking by the vacuum principle, best results
are obtained with a partial vacuum of eleven degrees, that is about five pounds below
atmospheric pressure. I have also found that, with this reduced pressure upon the
inside of the teat cup, the normal pressure of the atmosphere upon the outside of the
flexible lining is sufficient to cause it to squeeze the teat to the extent required to
give the best results.
The present invention consists in producing pulsation by connecting the annular
space of the teat cup by pipes to the main vacuum tank of the milking machine, and
in employing suitable valve mechanism, whereby communication is alternately
established between the tank and the annular space of the teat cup, and between
such annular space and the atmosphere.
I have also devised a pulsating teat cup, which is simpler and cheaper in
construction than those hitherto in use, and also other parts, to be hereafter
particularly described.
Referring to the drawings which form a part of this specification,
Fig. 1 is a perspective view showing the arrangement of my invention in a milking
stall.
Fig. 2. A side elevation; and
Fig. 3. A vertical section on 3-3 Fig. 2 of a valve and actuating mechanism.
Figs. 4 and 5 are respectively a side elevation and vertical central section of a teat
cup.
Fig. 6 is a cross section on 6-6 Fig. 5.
Figs. 7 and 8 are respectively a side elevation and plan of combination branch
pipes.
Similar reference letters indicate the same parts throughout the figures.
The teat cup (A) illustrated in detail in Figs. 4 5 and 6 is constructed as follows:-
A short piece of thin rubber tubing (a) is secured by rubber cement and binding upon

page_text: the end of the non-flexible tube (6), which is furnished with a pipe (g) for connecting
it to the milk withdrawal pipes.
A piece of non-flexible tube (d) bas its upper end beaded, and its other end inserted
in the tubing (a), to which it is secured by rubber.cement and binding.
The metal covering ring (e) is the same length as the tubing (a), which its surrounds,
and over which it is sprung, and its edges (f) secured together by solder or other
convenient means.
The air pipe (g) fixed upon the side of the tube (b) and ring. (e) allows air to be
withdrawn from and admitted to the outside of the flexible tubing (a) in a manner to
be hereafter described.
When the flexible tubing is new, there will be very little distance between it and
the covering ring (e), but I have referred to an annular space between them for
convenience in description.
Referring now to Fig. 1. The vacuum tank (h) is provided with an air pump (i)
operated by a hand wheel (j), by means of which the tank may be exhausted in a well
known manner. An ordinary relief valve (E) admits air to the tank in the event of the
required degree of vacuum being exceeded."
A pipe (1), which is preferably flexible, connects the tank (h) with a main pipe (m),
and a second flexible pipe (b) connects pipe (m) with the sealed milk receptacle (n).
The receptacle (n) has a flexible pipe (o) leading from it to a branch piece (p), to which
are attached the teat cups (A) by means of short pieces of flexible tube, which couple
upon pipes (c) at the bottom of the teat cups, shown in Figs. 4 and 5. A length
of transparent tube (o) in the pipe (o) makes visible the flow of milk:
It will be seen that when communication is established between the teat cups and
the tank (h) the degree of vacuum will be the same in both of them, and milk will flow
from the animal into the receptacle (n).
The air pipes (9) upon the teat cups are connected to a branch piece (t) which has
cominunication through a pipe (u) with a valve (v) upon the tank (h). The valve (v) is
operated by an eccentric upon the air pump, and alternately opens communication
between pipe (u) and tank (h), and pipe (u) and the atmosphere. The valve (v) is.shown
in detail in Figs. 2 and 3, which I will now describe.
The cylindrical casing (1) is provided with a screwed end (2) for attaching it to the
vacuum tank, and is provided with ports (3) and (5) opening to a pipe (4) to which is
attached the air pipe (u) before described.
The piston valve (6) is reciprocated by an eccentric (7)-having a strap and connecting
rod (9) upon the pump crank shaft (8), and it will be seen that when the valve (6) is
near the bottom of its stroke air is admitted through port (3) to the pipe (u) previously
referred to, through which it flows to between the flexible lining and rigid outer tubes
of each of the teat cups (see Figs. 4, 5, and 6) when the valve (6) is near the top of its
stroke the port (3) is closed, port (5) opened, and communication thereby established 4
between pipe (u) and tank (h).
The result of these operations is: that when pipe (u) is open to the atmosphere the
pressure upon the outside of the pulsating tube (a) is greater than the pressure upon
the inside which is in communication with the partially exhausted tank (h), the tube (a)
is in consequence caused to contract upon the teat of the animal, as shown in dotted 4
lines Fig. 5:
When pipe (u) is closed to the atmosphere it is open to tank (h), and pressure upon
either side of the pulsating tube is consequently equal, and the flexibility of the
rubber causes it to resume its normal position and to release its pressure upon the
teat of the animal.
Figs. 1, 7 and 8 show my method of constructing and combining the branch pipes
of the milk and air tubes respectively.
The branch piece (t) upon the main air tube (u) is fixed upon the branch piece (p)
of the milk pipe (o). The branches (p¹) upon the branch piece (p) are bent up, and the
branches (1) upon branch piece (t) bent down to bring their ends as nearly as possible
in one plane for convenience in placing the teat cups upon the teats of the animal,

page_text: A rubber socket (w) at the top of the teat cup fits closely to the teat and ensures a
tight joint.
Having now particularly described and ascertained the nature of my inven-
tion, and in what manner the same is to be performed, I declare that what I
claim is:
1. The improved method of producing pulsation of the flexible lining of the teat
cups of milking machines, consisting in connecting the annular space between said
flexible lining and the rigid outer tube of the teat cup, by pipes to the main vacuum
tank of the milking machine, valve mechanism being employed, whereby
communication is alternately established between said tank, and the annular space in
the teat cup, and between said annular space and the atmosphere substantially as
specified.
2. A pulsating teat cup constructed of a flexible rubber tube (a) between and
connected to the non-flexible tubes (b) (), a non-flexible covering ring (e), forming an
outer casing for tube (a) and an air-pipe (9), communicating with the main air pipe of
the machine substantially as and for the purposes herein described and illustrated in
the accompanying drawings.
3. The combination in apparatus for producing pulsation in the teat cups of milking
machines of a valve for alternately opening communication between the vacuum tank
and the annular space of the teat cup and between such annular space and the
atmosphere, such valve being operated by an eccentric upon the crank shaft of the air
pump substantially as herein specified and illustrated.
4. In combination the air pump crank shaft (8), eccentric (7), strap and connecting
rod (9), piston valve (6), casing (1), having ports (3) (5) opening into pipe (4), the
tube (u), and teat cup (A), substantially as and for the purposes herein described and
illustrated in the accompanying drawings.
5. The combination in apparatus for producing pulsation in the teat cups of milking
machines, of the air branch piece (t) arranged above and connected to the milk pipe
branch piece (p), the several branches upon the branch pieces (t) and (p) being arranged
with their openings in one plane substantially as, and for the purposes herein specified
and illustrated.
6. The combination and arrangement of parts comprising my improved apparatus
for producing pulsation in the teat cups of milking machines, the whole constructed,
arranged, and operating substantially as and for the purposes herein described and
illustrated in the accompanying drawings.
1004
HASELTINE, LAKE & Co.,
45 Southampton Buildings, London, W.C., Agents for the Applicant.