EP0148257A1

EP0148257A1 - A teat cup claw

Info

Publication number: EP0148257A1
Application number: EP19840902733
Authority: EP
Inventors: Walter Georg Whittlestone; Claude Richard Evans
Original assignee: Alfa Laval Agri International AB
Current assignee: Alfa Laval Agri International AB
Priority date: 1983-07-04
Filing date: 1984-07-03
Publication date: 1985-07-17
Also published as: NZ204807A; DK96185A; WO1985000270A1; JPS60501938A; DK96185D0

Abstract

Un dispositif à ventouses de trayon pour une trayeuse mécanique comprend une pluralité d'entrées débouchant chacune d'elles dans une chambre, une ouverture de sortie partant de chacune de ces chambres, des moyens de soupape disposés dans chaque chambre entre son entrée et sa sortie, ces moyens de soupape étant sensibles à un différentiel de pression. Selon l'invention, le passage d'entrée (13) et le passage de sortie (19) de chaque chambre (14) sont disposés chacun tangentiellement à la chambre.A teat suction cup device for a mechanical milking machine comprises a plurality of inlets each opening into a chamber, an outlet opening from each of these chambers, valve means arranged in each chamber between its inlet and its outlet , these valve means being sensitive to a pressure differential. According to the invention, the inlet passage (13) and the outlet passage (19) of each chamber (14) are each arranged tangentially to the chamber.

Description

A teat cup claw

This invention relates to a teat cup claw.

Any fall in vacuum in the milk collecting system of machine milking apparatus causes a reverse air flow. A major source of air consumption is during changing of the teat cups from one cow to another and the sudden changes associated with this procedure are of such a nature that they exacerbate the rate of new infections inflicted on the cows involved. Thus, there is a need for a means to reduce the amount of air consumed at the times of cup removal and application.

A fall in vacuum in the milk collecting system can also cause a reverse flow of potentially infected milk from the claw to the teat cups. This can arise by milk droplets being present in the reverse air flow, these milk droplets being conveyed during reverse air flow from the claw to the cups. There is therefore also a need for a means to restrict the reverse flow of milk.

The object of the present invention is to provide a teat cup claw which operates to substantially reduce the amount of air flowing into the machine during teat cup changing.

It is also an object of the present invention to provide a teat cup claw whereby reverse flow of potentially infected milk is prevented.

According to a broad aspect of the invention there is provided a teat cup claw for machine milking apparatus comprising a plurality of inlets each of which opens into a chamber, an outlet opening from each said chamber, valve means disposed within each said chamber between the inlet and outlet thereof, said valve means each being responsive to a pressure differential, the construction and arrangement of each chamber with its inlet and outlet being such that the inlet and outlet are each disposed tangentially to the chamber.

In the more detailed description of the invention which follows reference will be made to the accompanying drawings in which:

Figure 1 is a top plan view of a first form of the teat cup claw according to the invention,

Figure 2 is a side elevational view of the teat cup claw shown in Figure 1,

Figures 3a and 3b are detailed side elevational views of the chamber, valve means, inlet and outlet showing the valve respectively in the open and closed positions, and

Figures 4, 5 and 6 correspond to Figures 1, 2, 3a and 3b but show a second form of the teat cup claw according to the invention.

The teat cup claw 10 is formed by a body 11 which preferably is constructed in three part, the upper part of which (not shown) is detachable and provides pulsator connections of the normal alternating pulsation system. In the situation where simultaneous pulsation is required the normal alternating connector would be replaced by a simultaneous pulsation connector, however, this forms no part of the present invention as will be appreciated by those skilled in the art. The central portion of the body 11 provides milk inlet connections 13 together with valve chambers 14 and valve mechanism parts 15, 16, 17, 18, 19 which again are detachable from the lower portion comprising outlet passages 19 and outlet opening 12.

The lower portion of the body 11 of the claw has an outlet opening 12 and this is adapted for fitting to a milk line. This outlet 12 is connected internally to outlet passages 19 with both outlet passages 19 and inlet 13 opening into a chamber 14. As can be seen from the drawings each inlet 13 opens into its own chamber 14 with outlet passages 19 extending from each chamber 14 to ultimately connect with the outlet connection 12.

Each, chamber contains a diaphragm operated valve. The valve in simple terms consists of a valve seating 15 in which there is an opening 15a. A valve member 16 is attached to a valve stem 17 which in turn is attached to a valve diaphragm 18. In the two forms of the invention as illustrated in the drawings the diaphragms 18 are situated externally in the body 11.

Referring primarily to Figures 3a and 3b there is shown the valve in its opened and closed positions respectively and it will be seen that in the closed position the tapered base of the truncated conical valve member 16 is seated within the opening 15a in the valve seating 15.

The milk inlet connector 13 enters the valve chamber 14 tangentially and milk thus flows with minimum turbulence because of the tangential configuration. When the valve 16 is in the open position as shown in Figure 3a the milk flows with circular motion through the valve port or opening 15a into the outlet portion 14a of the chamber 14. In the preferred form of the invention the outlet passage 19 is situated tangentially to the chamber as is shown in Figure 3a.

The valve 16 is held in the closed position (Figure 3b) by a spring (not shown) when there is no vacuum in the valve chamber 14. A by-pass port 20 is provided by a small hole in the valve seat 15 though it can also be provided by a slot in the valve seat itself. When a vacuum is applied to the claw the valves remain closed, however, there is a small air flow through the valve bypass 20. When a teat cup is applied to the teat of an animal the moment the teat seals into the cup the vacuum rises in the vacuum chamber, the operating diaphragm 18 moves under the influence of the pressure differential across it and so opens the valve thus permitting full flow. In the event of the teat cups falling off or during changing of the teat cups from one animal to another a loss in teat cup vacuum causes an immediate closure of the valve.

The teat cup claw according to the present invention is of such a construction and arrangement that it substantially reduces air flow into the milking machine during cup changing. If a teat cup Is to fall off during milking vacuum is conserved and air flow into the fallen cup greatly reduced so elimiriating the sucking of gross contamination into the cluster.

With the positioning of the inlets 13 and outlets 19 in the tangential manner as illustrated there is a "cyclone action" and therefore droplets in milk entrained in an air stream flowing from the claw to the teat cup are thrown out so greatly reducing the possibility of reverse flow of milk into the teat cup and so reducing the possibility of infection movement. This tangential entry and exit of milk within the valve chambers 14 results in non-turbulent flow which reduces damage caused to the milk by turbulence.

The diaphragms 18 are preferably located so as to be accessable as illustrated and this accessability allows the milker to have an immediate over-riding control of the teat cup vacuum should this be required. Manual depression of the diaphragm immediately opens the valves.

At high liquid flow rates such as occur during cleaning of the milking equipment the cyclone action through the claw results in high velocities of the cleaning liquid against the milk contact surfaces so ensuring good cleaning. During reverse flow cleaning the claw holder in the bail acts to cause the opening of the control valves so permitting liquid flow without the action of vacuum. The substantial reduction in the air flow requirements during cup changing decreases the reserve air requirements of the milking machine when the claw is in use. This can lead to a reduction in the size of vacuum regulator required and there are thus consequential decreases in the size of the vacuum pump which greatly reduces the power requirements of the milking machine. The improved vacuum stability makes it possible to reduce the claw volume so reducing reverse liquid flow within the claw.

The invention is open to modification and development within the broad scope of the invention as stated herein. The individual claw chambers for example make it possible to include electrical conductivity cells for the automatic diagnosis of mastitis based on the determination of quarter conductivity ratios.

Claims

1. A teat cup claw for machine milking apparatus comprising a plurality of inlets each of which opens into a chamber, an outlet opening from each said chamber, valve means disposed within each said, chamber between the inlet and outlet thereof, said valve means each being responsive to a pressure differential. charac te r i zed i n that the inlet passage (13) and the outlet passage (19) of each chamber (14) are each disposed tangentially to the chamber.

2. A teat cup claw according to claim 1, cha r a c t e r i z ed In that said valve means comprises a diaphragm operated valve.

3. A teat cup claw according to claim 2, char ac te r i zed i n that said diaphragm operated valve comprises a valve seating (15), a valve member (16), a valve stem (17) and a valve diaphragm (18).

4. A teat cup claw according to claim 3, ch a ra c t e r i z ed in that said valve member (16) is designed as a truncated cone and is seated within an opening (15a) in the valve seating (15).

5. A teat cup claw according to claim 3 or 4, c har a ct e r i z e d in that said valve seating (15) is provided with a by-pass port (20).

6. A teat cup claw according to anyone of the claims 3 - 5, ch ara c t e ri z ed i n that said valve diaphragm (18) is situated externally in the claw (10) so that it may be operated manually.