PROCEDURE AND MEANS FOR IMPROVING THE MILKING PROCESS

Abstract: Procedure and apparatus for improving the milking process of pipe milking machines with overhead milk pipe. The object of the invention is to improve the udder health of dairy cattle and to reduce the admixing of air to the milk, and thus to improve the stability of the milk quality. As taught by the invention, during the milking a continuous vacuum is maintained in the centre-piece (2) by conducting the air from the centre-piece by an overhead route to a vacuum pipe (3), and the milk by a lower route through a vacuum pipe (4) by the aid of a pump (6) into a milk pipe (12), wherein normal pressure advantageously prevails. The milk is drawn from the centre-piece (2) by means of a piston pump (6) governed by the pulsator (5) of the milking machine and utilizing the vacuum in the vacuum pipe. The piston (7) of the pump (6) sucks during the first phase of each dual beat of the pulsator (5) milk through the vacuum pipe (4) into the milk volume (17) of the pump and during the second phase pushes the milk into the milk pipe (12).

Description: Procedure and means for improving the milking process The present invention concerns a procedure and a means for improving the milking process. Currently, cows are mainly milked mechanically by means of a milk¬ ing machine, the operation of which is based on vacuum. In general use is a so-called can machine which milks the milk into a milk can with 20 1 capacity. The pipe milking machines, in which the milk is transferred by the aid of vacuum of the machinery directly into the farm tank are, however, becoming increasingly common. To the udders is attached a milking device, with each teat in its own teat cup. In the teat rubber is generated a vacuum of about 0.5 atmospheres, whereby the sphincter of the teat chamber opens and the milk runs out. It is not possible, however, to continue the sucking step without interruption until the udder is drained; it is instead discontinued and the teat cup is allowed to press the teat for a while, this being accomplished by applying atmospheric pressure in the pul- sation chamber defined between the teat cup and the teat rubber. These sucking and massage phases are repeated 50-60 times per minute. The operation of the milking machine affects the functional capa- bility and health of the udder. The poor other health of Finnish dairy cattle causes annually major financial losses to the dairy industry in Finland, the annual losses incurred directly by the milk producers being estimated at 300-400 million Finnish marks. In a healthy herd, one sick indi¬ vidual implies a great risk to the economy of the farm. For this reason, improvements of the milking apparatus are required by which one is enabled to reduce both the risk of falling ill and the risk ~ of spreading disease. In the pipe milking machines in current use, with overhead milk pipe, the vacuum varies in the teat rubber during milking, which is a partial cause for the "teat ends being wetted" with milk; this occurrence may be a contributory factor spreading bovine mastitis. Owing to the reasons mentioned above, the milking machine may in part be responsible for mastitis in cows. Furthermore, when the milk is transported from the place of milking in machines known in the art, it is necessary to conduct air into the milk through an aperture in the centerpiece. Accord¬ ing to the standards valid in the Nordic Countries, at least 4 1/min of air shall be introduced through the centerpiece. The unfavourable effects of air on the microbiological as well as physical quality of the milk are commonly known. Separation of air and milk is therefore important. Currently, the milk is carried under vacuum all the way to the collector tank. Thus, there is time for the milk to cool and for crystallization of the milk fat to come under way. When sub¬ sequently the milk is taken from the collector tank by the aid of a pump, this imposes great strain on the fat globule, which is in a "sensitive" phase of crystallization. When either com- pletely crystallized or uncrystallized, milk tolerates best all kinds of treatment, such as pumping. Attempts have been made to improve the health of cattle e.g. by reducing contamination in the cow-house air; this is one of the aims of the milking systems described in the German application print No. 2622371. The system disclosed in said reference is not well applicable in Finnish cow-houses, and it fails to disclose the designs as taught by the present invention. The object of the present invention is to correct the defects mentioned, i.e._, to make the milking done with a milking machine "kinder" to the udder and to improve the keeping quality of the milk. The invention is characterized in that by its aid a liquid under vacuum can be drawn into normal pressure, using for driving force the same vacuum level, controlled either by a separate valve or by a pulsator (in the milking machine) and causing reciprocating motion of a piston. This "function is made possible by the design of the pump, having on the drive side of the piston a larger surface than on its effective side. The difference between the drive and effective sides, the collar, is used for returning the piston and for pushing forward the liquid which has been drawn up. The means is moreover characterized in that, when operating as an ancillary to a milking machine, it allows separation of milk and air immediately after the centre-piece and conduction of the milk and the air away from the centre-piece apart from each other,,, which in turn enables the vacuum to be maintained at constant height in the connection body. When the means is properly shaped and dimen¬ sioned, it is possible with its aid to inhibit the flow of milk back into the short milk tubes. The working vacuum of a milking machine provided with this means can be regulated to meet the specific requirements of the cow. In the means of the invention, designed to operate with vacuum, the difference between the drive and utility sides is utilized in both directions by an exceedingly simple construction. In existing means, the vacuum present in the milk pipe has the effect that if a leak occurs in the milk p.ipe, contaminated air from the cow-house atmosphere will enter the milk pipe. In a pipe milking machine provided with the means of the invention, cow-house air is not mixed with the milk to the same extent as in the means known in the art because normal pressure prevails in the milk pipe and the milk is not transported by the aid of an air flow. Therefore no cow-house air will flow into the milk pipe through potential leakage points, such as taps and junctures, and this obviously reduces the contamination of the milk with micro¬ organisms from the cow-house air. The milk will not undergo any mechanical working either: it passes in substantially uniform flow towards the milk room. The features characteristic of the procedure of the invention are stated in the characteristic features part of the claim 1, and the features characteristic of the means of the invention are disclosed in the characteristic features part of claim 5. The invention and the advantages gainable thereby are described more in detail in the following, reference being made to the example of the drawing attached, the aim of which is to illustrate the invention, without confining the idea of the invention, and which presents schematically a pipe milking machine with overhead milk pipe, provided with an ancillary means according to the invention. The vacuum fluctuations acting on the teat end in the pipe milking machine known in the art have been substantially eliminated in the means of the invention by carrying the air and the milk by differ¬ ent routes from the centre-piece 2 provided with a float 18: the air overhead through the vacuum pipe 3 and the milk the lower way by the vacuum pipe 4. The float 18 has been so constructed that it also closes the mouth 21 of the air pipe if for one reason or another the surface of the milk rises too high. The weight of the float IS causes that the float to come off the aperture immediatel , when the milk level falls. The removal of the milk separately by the lower way is made poss¬ ible by a piston pump 6 governed by a pulsator 5 and utilizing the vacuum prevailing in the vacuum pipe 3, which is part of the milking means 1. In the example, the pump 6 has been connected to the dual suction tube 20 of the milking means, in parallel with the pulsation chambers (not depicted) . The operation of the pump OMPI fa is rendered possible by the difference in area between the air and milk surfaces 8,9 of the milk-sucking piston 7. The pushing force which the pump 6 is required to produce is in turn produced by carrying the vacuum, by the aid of the pulsator 5, to the "collar" 10 remaining below the air face 8. The vacuum pump generates a vacuum which can be used to supply work. The milk is in similar way under a vacuum of equal magnitude in the centre-piece 2. The pump 6 (a differential pump) enables the milk to be drawn into normal pressure, using for pushing force a vacuum of equal magnitude, whereby thus the milk, respectively air, areas 8,9 of the piston, being of different size, make the oper¬ ation of the piston possible. The push force of the pump 6 is needed to push the milk through the milk tube 11 into the milk pipe 12, where normal pressure has to prevail, in contrast to a conventional milking machine. The milk milked by utilizing the means of the invention is conduc¬ ted in normal manner from the teats through the teat rubbers 16 under vacuum to the centre-piece 2. During the suction phase, the pump 6 draws during the initial part of the dual beat of the pul¬ sator 5, milk which is present in the centre-piece 2; he.reby, the milk passes along the vacuum pipe 4 through the valve 14 into the milk volume 17 of the pump 6. The suction of the pump persists until the float 18 reaches the bottom of the centre-piece 2, whereby the milk flow ceases. During the latter part of the dual beat of the pulsator 5, or the compression phase, the piston 7 pushes the-milk through the valve 15 through the milk tube 11 into the milk tube 12, which slopes towards the farm tank (not depicted) , and the milk runs into the farm tank by gravity action. In the prototype that has been constructed, the milk pump 6 has been installed in the immediate adjacency of the centre-piece 2. The size and weight of the means may occasionally restrict a design of this type, and it is then possible to apply an embodiment OMPI in which the pump 6 has been disposed to the lower end of a pipe 13, hanging down from the air pipe 3, together with the pulsator 5 belonging to the milking means 1 (as has been imagined to be done in the design of the figure) . The centre-piece 2 may be so dimensioned that it is usable even for milking cows more sensitive to milking. The prototype has been dimensioned for milk output about 5 1/min when the beat rate of the pulsator 5 is 50 dual beats per minute. The capacity of the pump 6, again, is dependent on the beat rate of the pulsator 5. It is true, though, that the beat rate of the pulsator 5 also effects the milking capacity (in 1/min) . Furthermore, the invention allows continuous easy measurement and sampling of the milk quantity that has been milked. When milking with the means known in the art, a separate measuring apparatus is required, which is hung between the milking unit and the milk pipe. The apparatus takes a proportional sample from the milk pipe in order to measure the milk quantity (quantitative sample) . As taught by the invention, the pump 6 pumps milk only, and since the volume of the cylinder is known, a pick-up may be installed on the side of the pump to measure the length of the suction travel (or of the compression travel) of the piston 7, whereby the exact milk quantity can be determined. By conducting the milk from the milk volume 17 of the purr.p 6 during the compression step through a holg,of suitable size (sampling nipple 19) into a sampling vessel, it is also possible to obtain a proportional sample from the quar ity of the milk that has passed through the pump. In a milking machine provided with an accessory as taught by the invention, the admixing of air to the milk is considerably reduced from what it is now, because air cannot enter the centre-piece 2 by any other route but by the top of the teat rubbers 16 through OMPI fa the space between the teat and the collar of the rubber 16. In addition, equipment provided with the means of the invention treats the milk more gently than any apparatus of prior art, because the pump 6 causes the pump strain acting on the milk immediately after the milking when the milk has not had time to cool essentially and likewise crystallization of the fat has not yet come under way. When using the means of the invention, a collector tank is no longer indispensable, even though it may be necessary for cleaning or other reasons. Introduction of the ancillary means of the invention saves the costs arising from a milk pump, since it operates on the same vacuum as the rest of the milking machine. Introduction of the means in all likelihood enables the vacuum level in the vacuum system to be lowered and it will also otherwise reduce the power requirement, because lifting of the milk to the milk pipe and its further transporting is not accomplished with the aid of air flow. The ancillary means of the invention may be used in almost any milking machine with overhead milk pipe in current use in Finland. The invention may be varied and modified within the scope of the claims, in accordance with the conditions of service.

Claims: Claims 1. A procedure for improving the milking process of pipe milking machines provided with overhead milk pipe, characterized in that the milk and air are separated at an early stage in that in the centre-piece (2) a continuous vacuum is maintained during the milking by conducting the air from the centre-piece by the over¬ head route to a vacuum pipe (3) , the milk being carried by a lower route through a vacuum pipe (4) by the aid of a pump (6) into the milk pipe (12). 2. A procedure according to claim 1, characterized in that in the milk pipe (12) normal pressure is maintained, whereby the milk flows in the milk pipe sloping towards the milk house in substan¬ tially uniform flow. 3. A procedure according to claim 1, characterized in that the milk is drawn from the centre-piece (2) by means of a piston pump (6) governed by the pulsator (5) of the milking machine and utilizing the vacuum in the vacuum pipe. 4. A procedure according to claim 3, characterized in that the piston (7) of the pump (6) during the first phase of each dual beat of the pulsator (5) draws milk through the vacuum pipe (4) to the milk volume (17) of the pump and during the second phase pushes the milk into the milk tube (12). 5. An apparatus for use in a procedure according to claim 1,2,3 or 4, characterized in that a pipe milkinjg_machine known in itself in the art is provided with a piston pump (differential pump) (6) , a suction pipe (4) for drawing the milk from the lower part of the centre-piece (2) into the milk volume (17) of the pump, and with a tube (11) or equivalent for pumping the milk from the milk volume (17) into the milk pipe (12), where normal pressure prevails. 6. An apparatus according to claim 5, characterized in that from the upper part of the centre-piece (2) a pipe leads to the vacuum OMPI , WiPO _. tube ( 13) . 7. An apparatus according to claim 5 or 6, characterized in that the air and milk faces (8,9) of the pump piston (7) are of differ- ent size, the difference (10) of the areas (8,9) being used to return the piston (7) . ( 8. An apparatus according to claim 5,6 or 7, characterized in that it is provided with a pick-up to indicate the piston travel to the purpose of measuring the milk quantity. 9. An apparatus according to claim 5,6,7 or 8, characterized in that it has been provided with a sampling nipple (19) for obtain¬ ing a proportional sample in a separate vessel.

Inventors: OJALA LAURI, OJALA, LAURI
Applicants: OJALA LAURI, OJALA, LAURI
Application year: 1983
Main classification: A01J5
IPC codes: A01J5