Improvements relating to machine milking apparatus - Patent Review GB19610046054 19611222

Description

COMPLETE SPECIFICATION

Improvements relating to Machine Milking Apparats.

We, ALFA-LAVAL COMPANY LIMITE,a

British Company, of Great West Road,Brentford, Middlesex, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement:-

This invention relates to machine milking apparatus of the general kind compriing a (usually transparent) container, conected at its upper end to a vacuum pipe and through a flexible milk tube to a set of teat cups, and connected at its lower end through a flexible transfer tube to a milk pipe. During milking, the passage through the transfer tube is closed (as by flattening the tube locally to bring its opposite walls into engagement) and the milk is drawn by the vacuum into the container, where it collects. When a cow has been completely milked, the connection of the container to the vacuum pipe is closed and the transfer tube is opened, so that the milk is transferred from the container to the milk pipe, air being admitted to the container through the teat cups, or asepar- ate inlet, to take the place of the milk withdrawn.

In existing installations of this kind the transfer tube is formed by a length of plain tubing, which is preferably of fairly large diameter to allow for rapid transfer. When the milk pipe is situated above the collecting container, the transfer tube must be given substantial excess length, to allow for the formation of a180 bend without risk of restricting the passage through the tube.

To allow the contents (or a sample of the contents) of the collecting container to be discharged otherwise than to the milk pipe, the transfer tube may be formed in two sections, which are connected together in a readily disconnectable manner at a point between the milk container and the point at which the passage through the transfer tube can be closed.

In accordance with the presentinven- tion, there is provided a machine milking apparatus of the kind described, a large bore transfer assembly comprising an elbow piece of flexible material, having two tubular arms set at an angle to each other, one arm making a sealing fit with the outlet of the container, and the other arm being connected to the milk pipe, the elbow piece having at or near the junction of the two arms, a closable drain bore through which some or all of the contents of the container can be drawn off.

In this arrangement the specially shaped elbow piece obviates the need for an excessive length of tubing, and the provision of a drain bore allows the contents of the container to be drawn off without breaking a connection in the transfer tube.

Further features of the invention are pointed out in the appende claims.

In order that the invention may be properly understood, there is described below a machine milking installation embodying the invention, the installation being illustrated in the accompanying drawings, in which:-

Figure 1 is a diagrammatic view of the apparatus ;

Figure 2 is a cross section of a portion of the transfer assembly; and

Figures 3 and 4 are a cross section and a side elevation, respectively, of a novel form of valve used in conjunction with the transfer assembly.

The apparatus shown in Figure 1 comprises a milking cluster1 connected to a pulsator vacuum line 2 through a pulsator valve 3. Milk flowing through the cluster passes to a container 4 under the influence of a vacuum applied to the container by a milking vacuum line 6 which is connected to a source of vacuum through a liquid trap 7. Milk is passed from the container 4 to a milk line 8 by means of a transfer assembly 9. The transfer assembly can be closed by means of a pinch valve 10 when required. The milk line 8 leads to an interceptor vessel 11 connected to a milk pump for delivering milk from the inteceptor vessel to, say, a cooler (not shown).

A portion of the transfer assembly 9 is shown in cross-section in Figure 2. The assembly comprises a specially shaped elbow piece 20 having two tubular arms 21,22, connected together by a smooth curve, and defining a main boreof 28 dia- meter. One arm 21 is vertical and fits over a nipple 4A on the container 4 to make sealing engagement with the nipple.

The other arm 22 is incline upwardly at an angle of20 to the horizontal and has secured in it a rigid, stainless steel connector 23. The transfer assembly is completed by a rubber tube 24of 8"bore, and 18"in length, and isreleasably connected at one end to the connector23 and at its other end to the milk line 8.

Owing to the built-in curvature of the elbow piece, the tube 24 has only to be bent through a fairly small angle, and the overall length of the transfer assembly is substantially reduced by comparison with the plain tube used hitherto. The elbow piece and transfer tube assembly described herein has been used to replace a plain tube of 40"overall length.

Communicating with the main bore of the transfer assembly, and projecting from the outer side of the elbow piece 20 is a tubular outlet 26 having a drain bore of 'diameter. T-his outlet is 3iormally closed by a removable plug 27. An aper- tured ear may be formed on the elbow piece to receive the plug when not in use.

During milking the plug 27 is positioned in the outlet26 to close the drain bore; but if it is desired to draw off the contents of the container through the drain bore the plug is removed. There is also provided a sampling valve 30 comprising a rigid tubular body 31, the upper end of which is adapted to fit closely in the drain bore of the outlet 26. A valve ball 32 is formed integrally with a pair of resiliently flexible arms 33 and a ring 34 which snaps into a recess in the valve body 31. The valve is shown in its closed position in Figure 3, the ball 32 being held in sealing engagement with the lower outlet end of the valve bore by virtue of the arms 33 being held elastically stretched. The valve can be opened by the pressure of the finger applied laterally, say left to right in Figure 4, so that the arms 33 stretch and bend to allow the ball tot be displaced to open the valve. The valve is readilyreclosed, by hand, by pushing the ball in the opposite direction. It is found that the valve can be opened and closed very easily and quickly by hand, making it suitable for use when drawing off small samples of milk direct from the container.

The elbow piece 20, and the member comprising the parts 32, 33 and 34 of the sampling valve 30 may be moulded from synthetic rubber. The rigid connector 23 is conveniently secured in the arm 22 of the elbow piece by having the arm bonded to it during the moulding of the elbow piece. The plug 27 and valve body 31 may be moulded in high impact ebonite.

It will be understood that the invention is not limited to the particular embodiment described, dimensions and other details of construction being variable to suit particular requirements.