A SYSTEM FOR REGULATING THE VACUUM IN EQUIPMENTS FOR MILKING MILCH ANIMALS

Abstract: System for regulating the vacuum in equipments (M) for milking milch animals, comprising: a first centrifugal vacuum electropump (E), driven by an electric engine (2); a vacuum line (L) connected between said first electropump (E) and the milking equipment (M); a sensor (S) for taking the vacuum on said line (L); an inverter (I) that modulates the revolutions of the electric engine (2) of said first electropump (E); characterized in that it comprises; a valve (V) for regulating the vacuum, applied onto said line (L); at least a second centrifugal vacuum electropump (E); at least one remote-control switch (T) for said second electropump; a control board (P) for managing the system; wherein said control board (P) checks the vacuum level taken by the sensor (S) and besides modulating the first electropump (E) by means of the inverter (I) controls the starting and turning off of said second electropump (E) by means of the relative remote-control switch (T), for keeping the predetermined vacuum value constant, in co-operation with the vacuum regulation valve (V).

Description: "A SYSTEM FOR REGULATING THE VACUUM IN EQUIPMENTS FOR MILKING MILCH ANIMALS" The present invention concerns a system for regulating the vacuum in equipments for milking milch animals. The equipments for milking known and used at present are operated through a vacuum line that feeds the different groups and devices for milking and milk transport. The vacuum line originates from a pumping group that must maintain in said line a determined vacuum level, predetermined according to the capacity of the milking equipment. However, during the milking operations the vacuum level in the line of the equipment tends to undergo to variations according to the milking, washing, drying phases etc, or following to casual and unexpected moves. Therefore, the main problem to solve consists in reacting to such variations of the line vacuum for restoring the predetermined vacuum level during the project and the installation of the equipment. For solving said problem, at present one single vacuum pump with lobes or with gears is used which is piloted by an inverter through an interface that receives the value of the vacuum in line taken by a sensor, and consequently regulates the revolutions of the engine of the vacuum pump. Such a regulation system has the advantage that it follows, moment by moment, any request of the milking equipment but, at the same time, it also shows some disadvantages. The first is that, under these conditions, the pump must be a volumetric pump with lobes or with ears, which means that it is very loud; that it has an efficiency lower than the one of a centrifugal pump with blades; that it is dimensioned according to the maximum requirement of the equipment (which occurs very seldom), but that it is forced to work as a rule according to the values of its own particular curve, far f om the possibility of optimal efficiency. Therefore, such a kind of equipment is very expensive due to its dimensions as well as to the kind of pump used and due to the use of an inverter able to regulate the number of revolutions of the electric engine that drives said pump. For solving said problem and making the equipment less expensive in its realization phase, a plurality of vacuum pumps are used, mainly centrifugal blade pumps, connected with a battery, all always working during the milking operations and dimensioned in such a way as to assure the efficiency of the maximum emergency capacity of said equipment. A vacuum valve with a mechanical or pneumatic working is provided on the line of the equipment for regulating the vacuum level, gauged for balancing the excessive vacuum value caused by the pumps, by sucking air from the outside. The components of this second vacuum regulation system are quite less expensive that those of the first mentioned system, but they cause an electric energy waste, because the instant use always is the maximum one. It is the aim of the present invention to eliminate all above mentioned inconveniences. It is the aim of the present invention to realize a system that makes use of not too expensive components, furthermore highly reducing the superfluous electric energy wastes. In other words, it is the aim of the present invention to reduce the investment to a minimum, optimising the efficiency of the equipment. The aims set forth are reached by means of the system according to the present invention, for regulating the vacuum in equipments for milking milch animals, comprising: - a first centrifugal vacuum electropump, driven by an electric engine; - a vacuum line connected between said first electropump and the milking equipment; - a sensor for taking the vacuum on said line; - an inverter that modulates the revolutions of the electric engine of said first electropump; characterized in that it comprises: a valve for regulating the vacuum, applied onto said line; - at least a second centrifugal vacuum electropump; - at least one remote-control switch for said second electropump; a control board for managing the system; wherein said control board checks the vacuum level taken by the sensor and - besides modulating the first electropump by means of tlie inverter - controls the starting and turning off of said second electropump by means of the relative remote-control switch, for keeping the predetermined vacuum value constant, in co-operation with the vacuum regulation valve. The advantages obtained by means of the system according to the present invention mainly consist in the energy saving that may be obtained during milking, and in the possibility of modifying already existing equipments by means of simple devices available on the market, managed by a special control board. The present invention will be described more in detail hereinbelow relating to the enclosed drawings in which some embodiments are shown. Figure 1 shows the scheme of a system for regulating the vacuum in equipments for milking milch animals according to the present invention. Figure 2 shows the scheme of a variant of the system of figure 1. Figure 3 shows the electric scheme of the control board that manages the system according to the present invention. Figure 4 shows a variant of the electric scheme of the control board. Relating to the details shown in the enclosed figures, the system for regulating the vacuum in equipments M for milking milch animals according to the present invention comprises: - a plurality of vacuum electropumps E; - a vacuum line L; - a vacuum sensor S; - an inverter I; - a vacuum valve V; - at least one remote-control switch T; - a control board P. The milking equipment M according to the present invention may be of any known kind and usually it may comprise pulsating means, milking groups, pails or containers for the milk, pipings for transporting the milk, pumps for transporting the milk, etc. Advantageously, each electropump E comprises a centrifugal pump 1 with lades driven by an electric engine 2. The capacity and prevalence features of each electropump E are such as to cover a part of the maximum request of the milking equipment so that when they are all working, the maximum request may be satisfied. The vacuum line L comprises pipings for the connection between electropumps E and the equipment M, interception valves, vacuum level gauges and interception devices for known liquids, not shown. Furthermore, line L comprises at lease one vacuum sensor S and one vacuum regulation valve V. The vacuum sensor S may be analogic or analogic/digital and takes the level on the vacuum line, transforming the same into an electric signal. With the analogical sensor shown in figure 3, the driving of the second vacuum electropump E occurs through a comparative circuit C; with an analogic/digital sensor, i.e. with digital indication of the limit levels shown in figure 4, the driving of the second vacuum electropump E is direct. The vacuum regulation valve V is advantageously of known kind with mechanic or pneumatic driving and may be gauged at a level of optimal vacuum for the working of the milking equipment. In a variant of the system according to the present invention shown in figure 2, said valve V preferably is of electromechanical kind and may be driven from the control board P. Inverter I is of known kind and allows to vary the number of revolutions of the electric engine of a first electropump E, so as to modulate the capacity of said electropump. The remote-control switch T is of known kind and allows starting or stopping the electric motor 2 of an electropump E. The control board P allows managing the whole system and mainly comprises: a feeding circuit A; a comparative circuit and a circuit for the regulation of the intervention limit C; a priority circuit of the washing vacuum VL; at least one delay circuit R of the pump(s) besides the first one; at least one timing circuit CT of the pump(s) besides the first one. Starting from an external feeding that advantageously should be of 24 Vcc, tlie feeding circuit A of the control board P creates the feeding tensions of the comparative and timing circuits. The comparative circuit and the circuit for regulating the intervention limit C compares the signal coming from the vacuum sensor S with the defined vacuum reference and generates the reference signal of the speed to be sent to the inverter I and to the delay circuits R. The priority circuit of the washing vacuum VL sets in after milking, during the washing phase of the equipment by means of the washing machine LAV, for defining the washing vacuum. The delay circuit R for the intervention of the pump(s) besides the first one determines tlie intervention delay of said pump(s) in case of variation of milking vacuum. The timing circuit CT of the pump(s) besides the first one determines the intervention time of said pmnp(s). As shown in figures 1, 3 and 4, the working of the system for regulating the vacuum in equipments M for milking milch animals is as follows. When starting the equipment M, the board P orders the inverter I to drive a first electropump E for assuring in said equipment the predetermined vacuum level, absolutely necessary and sufficient for the ordinary milking operations. If the vacuum line L level gets down below the minimum defined level, sensor S takes mat value and sends an electric signal to board P that works it our together with the comparative circuit C and orders the inverter I to increase the number of revolutions of the engine 2 of the first electropump E. If the vacuum in line L is not yet sufficient for assuring an optimal level, in spite of an increase up to the maximum value of the capacity of the first electropump driver by the inverter, board P orders a first remote-control switch T to operate a second electropump E, that gets to its particular capacity and prevalence. Advantageously, board P sends the signal to remote-control switch T only after a short time period (about two seconds) due to the delay circuit R, during which an insufficient vacuum level has been kept. The second electropump E is kept on by the remote-control switch for a time period predetermined through the timing circuit of the board P. When this time period expires and sensor S takes a sufficient vacuum level, the board orders the stop of the electropump or vice versa said electropump continues working until tlie required level has been reached. If the series of vacuum electropumps consists of more than two electropumps working in milking, as shown in figures 1 and 2, sensor S continues taking the vacuum level in line L during the working of the second electropump E. If, in spite of the starting of tlie second electropump, such level remains below the minimum value required by the equipment, board P orders a second remote- control switch T to start a third electropump E - after a determined time period (e.g. after four seconds) in which said value does not get over the limit - independently from the first and the second one, and with a system of series in fall (i.e. in timing sequence). Also the third electropump remains forcedly working for a defined time period (in case, different from the one of the second pump), through board P. When the defined time periods relatively for pumps 2 and 3 expire, if sensor S has taken a line vacuum value corresponding to the requested one, board P will order to stop the second and the third electropump. It is obvious that the same control may be used with an even greater number of vacuum electropumps. If, during the working of the second or of the other electropumps, the value of the vacuum line exceeds the optimal working one, the vacuum valve V starts working automatically and lets air into line L so as not to exceed the vacuum level defined when the milking equipment has been installed. According to figure 2, the vacuum valve V is an electromechanical one and the opening thereof is controlled by board P, as well as the modulation thereof.

Claims: CLAIMS 1. A system for regulating the vacuum in equipments (M) for milking milch animals, comprising: - a first centrifugal vacuum electropump (E), driven by an electric engine (2); a vacuum line (L) connected between said first electropump (E) and the milking equipment (M); a sensor (S) for taking the vacuum on said line (L); - an inverter (I) that modulates the revolutions of the electric engine (2) of said first electropump (E); characterized in that it comprises: a valve (V) for regulating the vacuum, applied onto said line (L); - at least a second centrifugal vacuum electropump (E); at least one remote-control switch (T) for said second electropump (E); a control board (P) for managing the system; wherein said control board (P) checks the vacuum level taken by tlie sensor (S) and - besides modulating the first electropump (E) by means of the inverter (I) - controls the starting and turning off of said second electropump (E) by means of the relative remote- control switch (T), for keeping the predetermined vacuum value constant, in co-operation with the vacuum regulation valve (V). 2. A system according to claim 1, characterized in that the vacuum regulation valve (V) is of mechanical kind. 3. A system according to claim 1, characterized in that the vacuum regulation valve (V) is of pneumatic kind. 4. A system according to claim 1, characterized in that the vacuum regulation valve (V) is of electromechanical kind piloted by panel (P). 5. A system according to claim 1, characterized in that panel (P) mainly comprises: - a feeding circuit (A); - a comparative circuit and a circuit for the regulation of the intervention limit (C); - a priority circuit of the washing vacuum (VL); - at least one delay circuit (R) of the pump(s) besides the first one; - at least one timing circuit (CT) of the pump(s) besides the first one. 6. A system according to the preceding claims, characterized in that the electrompumps (E) in addition to the second one working while milking are controlled by board (P) in an independent manner and in a falling series.

Inventors: SOLDI PAOLO, SOLDI, PAOLO
Applicants: AGRISISTEMI S R L, SOLDI PAOLO, AGRISISTEMI S.R.L., SOLDI, PAOLO
Application year: 2001
Main classification: A01J5
IPC codes: A01J5