110
A TAMPER-PROOF MILK DELIVERY CAN
[Vol. XXIV, Part II,
angle of 90° from the plane of the collar body, to form a small bracket for tying this
locking collar to the ring valve housing bracket. The thickness of this collar is
such that it fits snugly into the groove about the lower end of the faucet plug; the
collar is broad enough to extend, when in position, to the outer edge, or preferably
slightly beyond, on all sides of the plug housing, except where collar is open; the
throat of this collar is just deep enough that the outside surface of the tying bracket
comes firmly against the interior surface of a tying bracket on the ring valve housing.
Ring valve. This piece is made of Alkathene * a plastic which actually weighs
less than water. The valve is round in cross-section and three-fourth inch in dia-
meter outside; it may be between one-half and nine-sixteenths of an inch long.
Running longitudinally along its outside surface are six rounded grooves, each one-
fourth inch wide and about one-sixteenth inch or so deep. These allow milk to
flow past this valve when the faucet is assembled and opened. This piece has a
hole cut partly but not completely through it from the inside. This opening is
cut with a smaller diameter at its interior end than that at its exterior end, so it
just fits tightly over the outside of the milk outlet cone. When drawing milk
from the can, the force of the flowing milk pushes this valve away from the end
of the milk outlet cone. The milk then flows out of the milk outlet cone into the
ring valve opening, then backward between the milk outlet cone and the ring valve
opening until it can again flow outward through the rounded grooves, on the outer
surface of the ring valve, and within the inner wall of the ring valve housing, then
out through the ring valve housing.
Ring valve housing. This housing is tubular but with the outer opening at
right angle to the long axis of the piece; it is about one and three-fourth inches
long. The inside diameter is about twenty-seven-thirty-seconds inch for the first
one inch from the inner end. It then diminished to five-eighth inch rather quickly
but with rounded, not sharp, corners at the point at which the 90° turn begins near
the outer end. From this point this diameter further diminishes gradually into
through and to the outer end of the turned opening where it is about one-half of
an inch. The inner end of this housing is threaded inside for about one-fourth inch
to coincide with the threaded outlet of the faucet body. The thickness of the walls
of this piece is about one-eight of an inch. When the faucet is assembled the ring
valve is free to move in and out within this housing. The shoulders of the inside
surface of this housing at the point at which this diameter diminishes just inside
of the turn to the opening, are designed to stop the outer movement of the ring
valve, yet permit the interior of the housing at this point to be easily and satis-
factorily cleaned.
On the bottom outside surface of this housing at its inner end is a small bracket
about one-fourth inch wide, one-fourth inch long and one-sixteenth to one-eight
of an inch thick. It is bored with a three-thirty-seconds inch hole to admit a string
or wire with which to tie this housing to the plug locking collar tying bracket.
* See acknowledgment.