It is known to milk cows by means of so called quarter milking, which means that the milk from each teatcup connected to a single udder part is transported via a separate milk conduit to a milk-collecting tank. From this milk-collecting tank, the milk can then be transported either to a main storing and cooling tank for delivery or to a waste tank. When the milk has been received in the milk- collecting tank, the milk may be examined, for instance, for determining the content of bacteria or other micro- organisms. If the milk from only one udder part is infected the whole quantity of milk will be discarded, i. e. also the milk from the udder parts which possibly are not infected.

US-A-6,308, 655 discloses such a milking plant according to the prior art. The milk from all four teatcups is transported to a common local milk-collecting tank. The collected milk may then be transported to a main tank for delivery or be drained off if the milk is infected.

EP-A-385 539 discloses a milking plant for quarter milking with four separate milk meters for measuring the quantity of milk from each teat. From the four milk meters, the milk is transported via a discharge conduit to a common milk-cooling tank. Each milk meter includes a receiving member having a measuring chamber arranged to contain a certain quantity of milk. However, this quantity is less than the total quantity of milk obtained from an udder part during one milking

operation. Each milk meter also includes a conductivity sensor for detecting if an udder part is infected. If the milk from one udder part is infected, this milk may be transported separately via a three-way valve provided on the discharge conduit to a separate tank.

US-A-3,289, 633 discloses a bucket for collecting the milk from the four teats of an udder via four teatcups. The bucket includes partition walls dividing the interior of the bucket into for separate compartments. Each compartment is arranged to collect the milk from one separate udder part.

The bucket may be made in a transparent material enabling inspection of the quality and quantity of milk from each udder part. However, the technique disclosed in US-A- 3,289, 633 is only developed for collecting milk form one single animal. When the milking of one animal is finished the bucket will be filled and manual emptying of the bucket is needed.

EP-A-880 888 discloses a milking station with four teatcups and four separate transparent milk tanks. The milk tanks are arranged at the milking station for temporary storing of the milk from a respective teat. The milk tanks also include sensing means for sensing the quality of the milk. However, the discharge of milk from the milk tanks is not described in EP-A-880 888. It is merely mentioned that switch means may be provided for discharging milk to different storage tanks.

SUMMARY OF THE INVENTION The object of the present invention is to solve the problems mentioned above and to provide a milking plant which in an efficient manner separates milk of good quality from milk of poor quality.

This object is achieved by the milking plant initially defined, which is characterised in that the milk-receiving arrangement includes at least two separate connection devices, one for each local milk container, wherein each connection device is connectable to the main transport conduit for the transport of milk from the respective local milk container to the main transport conduit.

By means of these containers it is possible to decide whether the milk from the respective udder part is to be delivered or discarded before the milk is mixed with the milk from the other udder parts. It is thus possible to make an individual decision for the milk from each udder part. A highly efficient milk production is obtained since only milk, which is of poor quality, for instance infected, has to be discarded whereas all milk from healthy udder parts may be taken care of and be delivered.

According to an embodiment of the present invention, the milk-receiving arrangement includes an examination device arranged for separate examination of the condition of the milk in the local milk containers. By means of such an examination device, a reliable and efficient decision is obtained, which may be based on measurements made on the whole quantity of milk from the udder part. Preferably, the examination device is arranged to examine the condition of the milk in an automatic manner. The examination device may be arranged to deliver a value of at least one parameter indicating the condition of the milk and/or the animal. For instance, said parameter may include the electrical conductivity of the milk indicating a possible existence of an inflammation of the respective udder part. It is also possible to let the parameter indicate the pH of the milk and/or the butter fat content of the milk. The parameter may also be related to the somatic cell count (SCC) of the milk, see W098/50577, W098/50777 and WOOO/27183. Furthermore, the

parameter may as an alternative or complement be related to the concentration of lactoferrin (Lf), the concentration of blood serum albumin (BSA), and/or the concentration of lysozyme (Ly) in the milk. It is also possible to make a colour analysis of the milk to obtain a colour value indicating whether the milk contains blood, see EP-A-903 978.

According to a further embodiment of the present invention, the milking plant includes a waste conduit, wherein the local milk containers are connectable to the waste conduit.

Furthermore, the milking plant also includes a waste tank, wherein the local milk containers are connectable to the waste tank via the waste conduit for transport of the milk to the waste tank. Each milk-receiving arrangement may then include at least one pump arranged for pumping the milk from the local milk containers to the main transport conduit and the waste conduit, respectively. By means of such a waste conduit, and possibly also such a waste tank, the milk to be discarded can be disposed of in an efficient manner without any risk of being mixed with the milk to be delivered.

According to a further embodiment of the present invention, each connection device is adjustable to a first state connecting the respective local milk container to the main transport conduit or to a second state connecting the respective local milk container to the waste conduit. By means of such connection device, it is thus possible to direct selectively the milk to the main milk tank for delivery or to the waste conduit. Advantageously, the connection device is automatically adjustable to one of said first state and said second state. In order to obtain such an automatic operation, the milking station may include a control unit, which is connected to the connection devices and the examination device and arranged to control the

adjustment of the connection device in response to the value of said parameter.

According to a further embodiment of the present invention, each connection device includes a respective three-way valve device for directing the milk to the main transport conduit or to the waste conduit. The three-way valve device may be incorporated in the respective local container or each connection device may include an outlet conduit extending from the local milk container, wherein the three-way valve is arranged on the outlet conduit. Furthermore, each connecting device may include a first connection conduit extending from the three-way valve device to the main transport conduit, and a second connection conduit extending from the three-way valve device to the waste conduit.

Advantageously, each three-way valve device is arranged substantially immediately downstream the respective local milk container. In such a way, the length of the conduit transporting infected milk and healthy milk is reduced to a minimum. Moreover, each milk-receiving arrangement may include a first pump provided on the first connection conduit for pumping the milk from the local milk containers to the main transport conduit, and a second pump provided on the second connection conduit for pumping the milk from the local milk containers to the waste conduit.

According to another embodiment of the present invention, each connection device includes a first connection conduit extending from a lower end of the local milk container to the main transport conduit, wherein a first valve device is arranged at the lower end for opening or closing the first connection conduit, and a second connection conduit extending from a lower end of the local milk container to the waste conduit, wherein a second valve device is arranged at the lower end for opening or closing the second

connection conduit. Such a solution is advantageous from a hygienic point of view.

According to a further embodiment of the present invention, the local milk containers are at least partly made of a transparent material for permitting optical examination of the milk contained therein. By such a transparent material the farmer can observe any strange colour of the milk, caused by blood, for instance.

According to a further embodiment of the present invention, the milk-receiving arrangement includes quantity measuring members determining the total quantity of milk produced by each separate udder part during one milking operation. The total quantity of milk produced by each udder part during one milking operation may thus be easily determined by means of such measuring members of any suitable kind, a grading provided on the container for instance.

According to a further embodiment of the present invention, the milking station includes a teat-cleaning device arranged to permit cleaning of the teats, the teat-cleaning device including a teat-cleaning cup to be applied to the teat to be cleaned, a discharge line for discharging the cleaning liquid from the teat-cleaning cup and a collecting container for collecting the discharged cleaning liquid. This collecting container could advantageously have the same dimensions and the same shape as the local milk containers.

Thus the number of different components included in the milking stations can be reduced.

According to a further embodiment of the present invention, the milking station includes a washing device adapted to permit separate washing of each local milk container. If for instance only one quarter of the udder is infected by mastitis, only the milk from this quarter has to be

discarded. This specific embodiment makes it possible to wash and rinse only the teatcup, the milk conduit and the local milk container associated with the infected udder quarter in such a case. In this context, the washing device may include a washing unit and at least one washing nozzle, wherein the washing device, during a washing operation, is adapted to feed a washing liquid from the washing unit to the washing nozzle into one of said teatcups in such a manner that the washing liquid is fed through the teatcup, the associated milk conduit and the associated local milk container. Furthermore, the washing device is adapted to re- circulate the washing liquid back to the washing unit via a return conduit in order to provide a closed washing system.

According to a first alternative, the washing device may be adapted to re-circulate the washing liquid via the waste conduit. This is advantageous in connection with the washing and rinsing of one of the teatcups, milk conduit and local milk container, since the washing liquid does not have to be conveyed through the connection device for the transport of milk to the main transport conduit and through the associated local milk pump. According to a second alternative, the washing device is adapted to re-circulate the washing liquid via a portion of the connection device for the transport of milk to the main transport conduit.

This is advantageous in connection with a complete washing and rinsing of the milking station.

BRIEF DESCRIPTION OF THE DRAWINGS The present invention will now be described more closely by means of various embodiments thereof and with reference to the drawings attached hereto.

Fig 1 shows schematically a view of a milking plant according to a first embodiment of the present invention.

Fig 2 shows schematically a view of a milking plant according to a second embodiment of the present invention.

DETAILED DESCRIPTION OF VARIOUS EMBODIMENTS OF THE INVENTION Fig 1 discloses a first embodiment of a milking plant including a plurality of milking stations 1. In the embodiments disclosed herein, four milking stations 1 are provided, three of which are only schematically indicated.

However, it is to be noted that the invention is not limited to any specific number of milking stations 1, but any number from one and upwards is possible. The milking plant also includes a main tank 2 for storing and cooling the milk from the milking stations 1 before it is delivered to a dairy.

The milk is transported from the milking stations 1 to the main tank 2 via a main transport conduit 3 by means of any suitable method, such as by pneumatic transport by means of pressurised air, by vacuum, by gravity etc.

In the embodiments disclosed herein, each milking station 1 is a separate, substantially complete unit including substantially all components for the performance of the milking of the animals. The milking station 1 disclosed more closely in Fig 1 is intended for milking one animal at the time and includes a milking machine. The milking machine is illustrated by four teatcups 4 to be attached to the teats of the animal to be milked, a milk-receiving arrangement 5 and four milk conduits 6 connecting a respective one of the teatcups 4 to the milk-receiving arrangement 5. The milking station 1 may also include an automatic handling device (not disclosed) arranged to attach in an automatic manner the teatcups 4 to the teats of the animal to be milked. The automatic handling device may include a robot arm for gripping, holding and moving the teatcups 4.

The milk-receiving arrangement 5 is arranged to be connected to the main milk tank 2 via connection devices to be described more closely below and via the main transport conduit 3 for the transport of milk from the milk-receiving arrangement 5 to the main tank 2.

The milk-receiving arrangement 5 is also arranged to be connected to a waste tank 7 via said connection devices and via a waste conduit 8 for the transport of the milk from the milk-receiving arrangement 5 to the waste tank 7. The waste tank 7 may form a part of the milking station 1 or may be a common waste tank 7 for all milking stations 1 of the milking plant.

The milk-receiving arrangement 5 includes four separate local milk containers 11. Each container 11 is connected to a respective one of the teatcups 4 via a respective one of the milk conduits 6. Each container 11 is designed to contain the whole quantity of milk produced during one milking operation of one udder part of the animal. A vacuum or low pressure is applied to each local milk container 11 from a low-pressure source. In the embodiments disclosed herein, the vacuum source is a local vacuum pump 12, which is connected to the local milk containers 11 via a vacuum conduit 13 having a connection to each local milk container 11. A trap member 14, that prevents milk from reaching the vacuum pump 12, is provided on the vacuum conduit 13. By means of the vacuum pump 12, a vacuum, or a low pressure, is thus applied to the teatcups 4 in a conventional manner. It is to be noted that the milking machine also includes means (not disclosed) for providing a pulsating movement to teatcup liners (not disclosed) in the teatcups 4. The milk extracted from the udder parts is thus collected in a respective one of the local milk containers 11.

After the milking is finished, the milk contained in the local milk containers 11 can thus be pumped away from the milk-receiving arrangement 5 either to the main milk tank 2 or to the waste tank 7. In the first embodiment disclosed in Fig 1, the milk may be transported from the local milk containers 11 to the main transport conduit 3 by means of a local pump 15. In a corresponding manner, the milk may be transported from the local milk containers 11 to the waste conduit 8 by means of a local pump 16.

The milk-receiving arrangement 5 also includes an examination device arranged for separate examination of the condition of the milk in the local milk containers. In the embodiments disclosed herein, the examination device includes four separate examination members 21 arranged in connection with a respective local milk container 11. It is to be noted that the examination device may includes another number of examination members 21, e. g. only one examination member 21 which is moved between the different local milk containers 11. Each examination member 21 is arranged to deliver a value of at least one parameter indicating the condition of the milk and/or the animal. The parameter is preferably in the form of an input signal, e. g. an electrical signal, which is delivered to a control unit 22.

The input signal may be transferred in various ways to the control unit 22, for instance, by means of an electric wire, wireless communication etc. The control unit 22 includes a suitable processor for processing the input signal. The control unit 22 may also include or be connected to a database (not disclosed) providing historical data to be considered in the processing of the input signal.

A large number of various parameters may be detected by means of the examination members 21. The parameter may, for instance, include the electrical conductivity of the milk contained in the local milk container 11. The electrical

conductivity may be used to indicate if the milk is infected, and thus a possible existence of an inflammation of the respective udder part. In this case the examination members 21 may include two electrodes extending into the local milk container 11 to be in contact with the milk. The parameter may also be an indication of the pH of the milk in the local milk container 11 or the butter fat content of the milk. Also the values of other parameters related to the quality and/or quantity of milk may be determined by means of examination members 21 of various designs. Such parameters may be related to the somatic cell count (SCC), the concentration of lactoferrin (Lf), blood serum albumin (BSA), and/or lysozyme (Ly) in the milk, and/or a colour analysis of the milk.

In addition, the local milk containers 11 may at least partly be made of a transparent material for permitting optical examination of the milk contained in the local milk container 11. For instance, the local milk container 11 may include a transparent housing. Furthermore, a quantity measuring member determining the total quantity of milk in the local milk container 11, i. e. produced by each separate udder part during one milking operation, may be provided in connection with the local milk containers 11. Such members may for instance include a grading on a transparent housing of the local milk container 11.

As briefly mentioned above each local milk container 11 is selectively connectable to the main transport conduit 3 or the waste conduit 8 by means of the respective connection device. Each connection device is adjustable to take one of two states, i. e. a first state connecting the respective local milk container 11 to the main transport conduit 3 and a second state connecting the respective local milk container 11 to the waste conduit 8. Preferably, said adjustment to one of the two states is made in an automatic

manner. Thereby, the control unit 22 is connected to the connection devices and to the examination members 21, wherein the control unit 22 receives said input signal indicating a value of the parameter and transfers after said processing a control signal to the respective connection devices. The connection device is thus adjusted to one of said states in response to the value of said parameter delivered by the respective examination member 21. For instance, if the value of a parameter being the electrical conductivity exceeds a certain level the control unit 22 may transfer a control signal adjusting the connection member to the second state, wherein the milk is transported to the waste tank 8.

In the first embodiment disclosed in Fig 1, each connection device includes a first connection conduit 31 and a second connection conduit 32. The first connection conduit 31 extends from a lower end of the local milk container 11 to the local pump 15 and to the main transport conduit 3. The second connection conduit 32 extends from the lower end of the local milk container 11 to the local pump 16 and to the waste conduit 8. A first valve device 33 and a second valve device 34 are provided at the lower end of the milk container 11 and connected to the control unit 22. The first valve device 33 is arranged to open or close the first connection conduit 31, and the second valve device 34 is arranged to open or close the second connection conduit 32.

The first and second valve devices 31 and 32 may form a three-way valve incorporated in the lower end of the local milk container 11.

In the second embodiment disclosed in Fig 2, each connection device includes an outlet conduit 41 extending from the lower end of the local milk container 11. A three-way valve device 42 is arranged on the outlet conduit and connected to the control unit 22. The three-way valve can be adjusted to

direct the milk from the respective local milk container 11 to the main transport conduit 3 via a first connection conduit 43 and the local pump 15 or to the waste conduit 8 via a second connection conduit 44 and the local pump 16. In this second embodiment, each three-way valve device 42 is arranged substantially immediately downstream the respective local milk container 11.

It is to be noted that elements, which are included in the different embodiments and which have similar or identical functions, are provided with the same reference signs in the figures.

In the embodiments disclosed, the milking stations 1 also include a teat-cleaning device arranged to permit cleaning of the teats in connection with the milking. The teat- cleaning device includes a teat-cleaning cup 61 to be applied to the teat to be cleaned. A supply conduit 62 is connected to an inlet of the teat-cleaning cup 61 for supplying a cleaning liquid, e. g. water. A discharge line 63 is connected to an outlet of the teat-cleaning cup 61 for discharging the cleaning liquid from the cleaning cup. The discharge line 63 is connected to a collecting container 64 for collecting the discharged cleaning liquid. An outlet is arranged at the lower end of the collecting container 64 for leading away the used cleaning liquid to any suitable disposal arrangement. The container 64 is also connected to the vacuum pump 12. The cleaning liquid will thus be sucked through the teat-cleaning cup 61 into contact with the teat to be cleaned and out through the outlet to the collecting container 64. The collecting container 64 of the embodiments disclosed herein is substantially identical to the local milk containers 11, i. e. the collecting container 64 has the same dimensions and the same shape as the local milk containers. It is thus possible to produce the containers 11

and 64 in the same mould, for instance. Consequently, the manufacturing of the containers is simplified.

Furthermore, the milking station includes a washing device 70 adapted to permit a complete washing and rinsing of the components of the milking station 1 or a separate washing and rinsing of each teatcup 4, milk conduit 6 and local milk container 11. The washing device 70 includes a washing unit 71 for the supply of washing liquid and for receiving used washing liquid. The washing device 70 also includes at least one washing nozzle 72. In the embodiment disclosed, the washing device 70 includes four washing nozzles 72, one for each local milk container 11. Each washing nozzle is connected to the washing unit by a washing conduit 73.

During the complete washing and rinsing operation, the washing device 70 is adapted to feed the washing liquid from the washing unit 71 to the washing nozzles 72 into the teatcups 4. Consequently, the washing liquid is fed through the teatcups 4, the associated milk conduits 6 and the associated local milk containers 11. The washing liquid is then discharged from the local milk containers 11 via a portion of the associated connection device by means of the pump 15. Furthermore, the washing liquid may also be re- circulated by means of the pump 15 to the washing unit 71 via a return conduit 78, e. g. from the said portion of the connection device, in order to provide a closed washing system.

As mentioned above, one teatcup 4 and the associated milk conduit 6 and local milk container 11 may be washed and rinsed separately from the other teatcups 4 of the milking station 1. Such a separate washing and rinsing operation may be performed in a secure manner by opening one valve 79 provided on the respective milk conduit 6, wherein these valves 79 on the remaining milk conduits 6 are closed. The

washing liquid is then sucked by means of the vacuum pump 12 through the teatcup, the milk conduit 6 and the local milk container 11. From the local milk container 11 the washing liquid is transported away via the valve 34 and the conduit 32 by means of the pump 16 according to the embodiment disclosed in Fig 1. According to the embodiment disclosed in Fig 2, the washing liquid is transported from the local milk container 11 via the conduit 41, the three-way valve 42 and the conduit 44 by the pump 16. The washing liquid may then by discharged in a suitable manner, e. g. to the waste tank 7, or it may be re-circulated to the washing unit 7 by means of the pump 16 and via a three-way valve 80, a conduit 80a and the return conduit 78.

Also the teat-cleaning device may be washed by the arrangement disclosed. Washing liquid is sucked from the waste tank 7 via a washing conduit 81 into the teat-cleaning cup 61 by means of the low-pressure obtained by the vacuum pump 12. From the teat-cleaning cup 61 the washing liquid is sucked through the discharge conduit 63 into the collecting container 64. The washing liquid is then pumped via a circulation conduit 82 back to the waste tank 7 by means of the pump 16. The circulation conduit 82 has a valve 83, which during milking is closed and provides venting of the waste conduit 8.

The present invention is not limited to the embodiments disclosed but may be varied and modified within the scope of the following claims. It is to be pointed out that the connection devices, i. e. the conduits extending from the different local milk containers 11 to the main transport conduit 3 and to the waste tank 7 can be designed in a great number of various ways. The embodiments disclosed above are advantageous examples of such different designs. It is also to be noted that the milking plant according to the invention is applicable to all animals that can be milked, such as cows, horses, goats, sheep, etc.