Apparatus to be used in connection with Milking Machines for the Purpose of Automatically Disengaging the Teat Cups from Cows.
Year: 1893

page_text: Date of Application, 13th Sept., 1893-Accepted, 21st Oct., 1893
COMPLETE SPECIFICATION.
Apparatus to be used in connection with Milking Machines for
the Purpose of Automatically Disengaging the Teat Cups
from Cows.
I REUBEN WITHELL of Brookside in the Provincial District of Canterbury
and Colony of New Zealand, Dairy Expert, 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 :-
With existing milking machines the teat cups are suddenly disengaged from the
cow's teats at the termination of the milking operation and consequently no time is
allowed for complete stripping.
Now the principal object of my invention is to allow time for the complete
stripping of the teats after the main suction is stopped and before the teat cups are
disengaged from the teats.
According to my invention I employ a vacuum chamber with which the milk
pipe (to which the teat cup is attached) and the suction pipe of the air pump
communicate, said chamber being provided with a pipe by which air is admitted
under control. Inside this chamber there are levers supporting milk cups so
arranged and actuated that when the milking operation is commenced the suction
pipe is opened and the air inlet pipe closed simultaneously. The chamber is then
exhausted and the milk from the animal first flows into and fills the upper cup,
and then overflows into and fills the lower cup, the weight of the milk retaining the
levers in such position that the suction pipe will be kept open and the air inlet
pipe closed until the milk supply ceases. The cups each have a small orifice
through which the milk runs off from the upper cup to the lower cup and from the
latter to the receptacle or chamber in which the mechanism is contained. So soon
While the lower cup
as the top cup has emptied itself the suction pipe is closed.
is emptying itself the vacuum exerts a gentle stripping action upon the teats, the
hole in the cup being of such size that the emptying of the cup will occupy
sufficient time to enable the complete stripping of the teat to be effected before
the said cup is wholly emptied whereupon the air is admitted and destroying the
vacuum causes the teats to be gently released.
The vacuum chamber may be connected directly to a milk cau or other air
tight vessel or suspended by cords and connected to the milk can by a flexible
tube. The said vacuum chamber may, if desired, be fitted with only one lever
and cup.
It can also have the air pipe differently arranged as described
hereafter.
In order that my invention may be more easily understood, I will now proceed
to describe the same by reference to the annexed drawings, wherein
Figure 1 is a sectional view of the vacuum chamber connected with a receptacle
for the milk, showing the levers, milk cups and mechanism.
Figure 2 is a sectional view of a vacuum chamber having only one lever and
milk cup, and
Figure 3 is a sectional view of a further modification of my invention.
Figure 4 is a plan of one of the levers.
Referring to Figure 1, A is the vacuum chamber, B the suction pipe to which
the air pump is connected, C the milk pipe to which the teat tube is connected,
D the air inlet pipe, EE the upper and lower levers respectively adapted to
support the milk cups F F. These levers are pivoted near their centre on a
support G and are counterweighted at one end while their other end is turned up
and round a starting rod H which is provided with two pins a a' for depressing
the levers. The upper lever E is provided with a flexible pad b for closing the

page_text: end of the suction pipe B while the lower lever E' is provided with a similar pad c
for closing the end of the air inlet pipe D.
The vacuum chamber A has an outlet pipe d provided with a draw off cock e,
while the milk can 1 has a pipe f at top (or other convenient position) provided
with a stop cock the two being connected by a flexible tube with unions so as
to be easily disconnected.
When commencing operations, the suction pipe B is connected to the air pump,
and the milk pipe C is connected to the teat tube from the cow. The starting
rod H is then turned so that the pins a al depress the levers E E' thereby opening
the suction pipe B and closing the air pipe Ď simultaneously. The chamber A is
then exhausted and the milk flows into and fills the upper cup F thereby
retaining the lever E in its depressed position. The milk overflows into and fills
the lower cup F thus retaining the lower lever E' in its depressed position. The
starting rod H is now turned back to its first position, and so long as the milk
continues to flow, the suction pipe B will remain open and the air pipe D closed,
but as soon as the flow of milk ceases; the upper cup F is emptied by the milk
escaping through the hole in its bottom into the lower cup F¹.
When the upper
cup is empty the lever E rises and causes the pad b to close the suction pipe B
and while the milk is similarly running out of the lower cup F1 the vacuum is
exerting a gentle stripping action upon the teats, sufficient time being allowed for
the complete stripping of the teats before the lower cup is emptied, whereupon the
lower lever E' rises and removes the pad c from pipe D, opens said pipe, thus
destroying the vacuum, causing the teat cups to be softly released from the
animals teat. The milk may be allowed to run from the chamber A into the milk
can and when full the stop cocks e and 9 can be shut off, the flexible tube
disconnected and the can emptied and then reconnected (after having the air
drawn therefrom) without stopping milking operations.
i
Referring to Figure 2, J is the vacuum chamber, K the suction pipe, L the milk
pipe, M the air inlet pipe fitted with a cap for regulating the inflow of air. N is
the lever, O the milk cup, P the support on which the lever is fulcrumed. Q'is the
starting rod fitted with projection. The lever N is provided with a flexible pad k
for closing the end of suction pipe K, and a similar pad at opposite end for
closing air pipe M. The operation of this arrangement is similar to that shown in
Figure 1, with this difference, viz. :-that the one lever opens and closes the
suction and air pipes respectively, the admission of air being regulated by the cap i
so that it will take as long as may be desired before it destroys the vacuum during
which time the vacuum is exerting a gentle stripping action upon the teats until
the vacuum is destroyed when the teat cups are gently released.
Referring to Figure it will be seen that the arrangement is the same as in
Figure 2, except that the air pipe M is not closed and opened by the action of the
lever, but is always open to the air, the inflow of air being capable of being
controlled to such a nicety by the cap that the suction pipe K will easily exhaust
the air so admitted, and yet when the suction pipe K is closed, the stripping action
will be the same as described in relation to Figure 2.
It will be seen that each arrangement is a variation of the same apparatus, and
in each case there is a length of time allowed between the stoppage of the full flow
of milk and the disengaging of the teat cups, during which time a gentle stripping
action is maintained, thus ensuring the clean milking of the cows and avoiding the
objectionable method of maintaining full suction power up to the last, and then
suddenly releasing the teats.
By preference weighted levers have been adopted as the means of balancing the
milk cups, but the same results may be accomplished by other means of sustaining
the cups in position, as will be readily understood.
The vacuum chainber may be made of tinned steel or other suitable metal;.the
milk cups of tin or other suitable metal, while the levers and other parts may be of
brass or nickel plated, or any other suitable metal.

page_text: Having now particularly described and ascertained the nature of my said
invention, and in what manner the same is to be performed, I declare that what
1 claim is
1. The apparatus as shown in Fig. 1 to be used in connection with milking
machines for automatically disengaging the teat cups from cows, consisting of the
vacuum chamber A provided with suction pipe B, milk pipe C, and air inlet
pipe D, and containing starting rod H, levers E and E fulcrumed on rod or
support G and having respectively milk cups F and F and flexible pads b and c
substantially as and for the purposes herein described and as illustrated in the
annexed drawings.
2. The modification of the said apparatus as shown in Fig. 2 the vacuum
chamber containing only one lever N having flexible pads k and and milk cup O;
the air pipe being fitted with an adjustable cap i, substantially as and for the
purposes herein described and as illustrated in the annexed drawings.
3. The further modification of the said apparatus as shown in Fig. 3 the lever
having no flexible pad at the weighted end and the inner end of the air inlet pipe
being always open but the inlet regulated by cap i, substantially as herein
described and illustrated in the annexed drawings.
Dated this 26th day of July A.D. 1893.
REUBEN WITHELL.