IE40264B1

IE40264B1 - Valve for automatically regulating the operating vacuum ofof milking systems

Info

Publication number: IE40264B1
Application number: IE241874A
Authority: IE
Original assignee: Westfalia Separator Ag
Priority date: 1973-12-19
Filing date: 1974-11-25
Publication date: 1979-04-25
Also published as: BE820858A; IT1024618B; ES433084A1; IE40264L; AT341264B; NL7414211A; FR2255012B1; CH578821A5; NL164728C; DE2363125B1; FR2255012A1; GB1440901A; DE2363125C2; NL164728B; ATA783674A

Description

4 0 2 6 1 This invention relates to a valve which automatically regulates the operating vacuum for milking systems, whereby the said valve j.s provided with at least one air inlet permitting, in the case of varying vacuum the admission into the system of a quantity of atmospheric air controlled by the valve so as to permit the compensation of the variation in the vacuum from the desired value. The hitherto used regulating valves do not satisfactorily fulfil this function.

German DOS P 23 45 235.9 already proposed a vacuum regulating valve which substantially eliminates the disadvantages of the hitherto used valves and satisfies the standards Tor such valves. In the valve according to the above DOS, the diaphragm which controls the air inlet is acted upon in the opening direction by .1 force which is obtained from the product of the full pressure difference between atmospheric pressure and operating vacuum times the effective diaphragm surface. In i lie closing direction acts a loading weight and a force 4026 J which is formed from the product of the pressure difference between atmospheric pressure and the operating vacuum times the cross-section of the air inlet.

The special feature of this valve, i.e. controlling the vacuum in the system as a function of the load imposed on the installation by the consuming device or as a function of its air throughput provides considerable advantages compared with the hitherto known valves. It functions horizontally with low and medium loads but under optimum loading has a falling tendency. Therefore, with maximum loading of the installation by the consuming device, the valve does not sufficiently constrict its air inlet.

The search for a new solution to this problem has been based on the fact that when the milking system is loaded to the maximum by the consuming device, the air throughput through the regulating valve must be small and vice versa. If the valve according to the above indicated DOS does not sufficiently constrict the air inlet when the consuming device places a high load on the system the force acting on the diaphragm in the opening direction is too great.

The problem of the invention is therefore to construct a vacuum regulating valve in such a way that the force acting in the opening direction is smaller when the system is under a high load than when it is under a low load.

According to the invention, the problem is solved in that it is not the full pressure difference between atmospheric pressure and operating vacuum which acts 40264 on the di.iplir.nim In the open i "'l illrivi 1i<ii l>ut .in .nite-in. 11 i i*.11 I y .iii> I i ill'i n I 11'I y variable pressure il I I IVri'in'i1 which is small when I In' system is unilor .1 high lo.ui and increases with decreasing load.

A valve for automatically regulating the operating vncuum in milking systems according to the invention comprises a valve casing, a diaphragm firmly clamped in the valve casing, firmly connected to a valve body and separating two control chambers from one another in which one control chamber is connected via an auxiliary valve with a chamber adapted to be connected to the pipe system supplying the ojerating vacuum and is provided with one or more calibrated air inlets and tiio other control chamber is connected to atmospheric air through a filter.

Although the invention may be performed in various ways two specific embodiments will now be described with referencf. to the accompanying drawings in which Figure 1 is a view partly in cross section of a weighted vacuum regulating valve with an auxiliary v.live having .1 diaphragm according to one embodiment of I lie i nvent i 011, Figure 2 is a half the plan view of the valve according to Fig. 1, and Figure 3 is a spring-loaded vacuum regulating v.i 1 vi- with -iii auxiliary valve having 1WC' diaphragms, according to another embodiment of the invention.

As shown in the drowings I is the pipe under vacuum whose port ion 2 leads to the vacuum pump and whose portion .1 :o the consuming devices comprising the pulsators directly connected thereto and the milking 40264 tackle indirectly connected thereto. The lower portion of valve casing 4 with air inlet 5 is screwed firmly to vacuum pipe 1. Valve body 6 controlling air inlet 5 carries a counterweight 7 and is connected with the 5 diaphragm 8 of the control valve. Valve body 6 is acted upon in the opening direction by the force which results from the pressure difference in control chambers 9 and 10 times the effective surface area of diaphragm 8. In the closing direction it is acted upon by counterweight 7 10 and the force formed from the pressure difference in chamber 9 and pipe 1 times the cross section of the air inlet 5. Control chamber 9 is connected with atmospheric air via air filter 11 (Fig.2). During operation, control chamber 10 is connected via channel 12, restrlctor 15 13 of the auxiliary valve, orifices 14 in cap 15 and a pipe 16 with pipe portion 3 which is under vacuum.

Atmospheric air passes through air filter 17 into chamber 18 which is connected with control chamber 10 by means of one or more calibrated orifices 19. In 20 addition, chamber 18 is connected with the control chamber 21 of the auxiliary valve via larger openings 20 so that in this latter chamber full atmospheric pressure always occurs. Control chamber 22 of the auxiliary valve is connected via pipe 16 with pipe 3 which is under the 25 existing operating vacuum. Cap 15 which is supported on diaphragm 23 of the auxiliary valve is acted upon in the closing direction by the compression of a spring 24 whereby this compression is regulated by screw 25 and spring washer 26 and is held in the set position by means of a knurled 30 nut 27. Thus simultaneously the desired operating vacuum - 5 - 4 0 2 6 1 is set. A vacuum gauge is indicated at 28. The individual components of the valve are held together by means of a clamp 30 (Fig.2).

The valve functions in tho following manner: r.

When the milking system is not operating atmospheric pressure exists in all the control chambers 9, lO, 21 and 22. Valve bodies 6 and 29 are located on their seats due to counterweight 7 acting in the closing direction Of spring 24 acting in the closing direction.

After switching on the vacuum pump without connecting up consuming devices, the full operating vacuum builds up in pipes 1,2 and 3 and via pipe 16 also in control chamber 22 of the auxiliary valve. 15 Diaphragm 23 upon which atmospheric air continues to act from below raises the valve cap 15 counter to the spring compression until the desired operating vacuum is reached. Air is then drawn from control chamber 10 of the main valve through orifice 12, 20 orifices 14 and pipe 16. Simultaneously, atmospheric air flows into valve chamber 10 through the calibrated orifice 19 that in chamber lO a low control vacuum builds up which differs from the operating vacuum. If consuming devices load the system, the operating vacuum 25 easily drops and auxiliary valve 29 is constricted to a greater extent by the compression of spring 24. The control vacuum in valve chamber lO also easily drops and main valve 5 is correspondingly further closed.

As a result of the valve according to the 30 invention, the pressure difference acting in the opening - 6 - 40264 direction on diaphragm 8 is larger when there is a small \ load on the system and smaller when there is a high load on the system. If valve body 6 sticks or jams, the valve rupture force is automatically increased because a higher 5 vacuum builds up in control chamber 10 via the further opening of auxiliary valve 29 and the force resulting from the pressure difference and the surface area of diaphragm 8 is larger than that of the counterweight 7 and the force of the pressure difference on the cross-section 10 of air inlet 5.

The embodiment of Fig.3 differs from that of Fig. 1 in that the single diaphragm 23 in the first embodiment is replaced by two diaphragms 23a and 23b with different diameters and in place of counterweight 7 a 15 spring 31 acting in the closing direction is provided. The existing operating vacuum is effective in control chamber 32 via pipe 16 and in control chamber 35 via channels 33 and 34. When the operating vacuum varies the opening force acting on valve body 29 also varies so that 20 with a high operating vacuum more air is removed from control chamber lO and with decreasing operating vacuum less air is removed therefrom. The auxiliary valve can also be constructed in a different manner.

As a result of both embodiments, a substant-25 ially uniform operating vacuum is obtained over the complete capacity range of the vacuum pump which vacuum in its constancy is greatly superior to that in the existing systems. - 7 - 4 0 2 6 4

Claims

1. A valve for automatically regulating the operating vacuum in milking systems comprising a valve casing, a diaphragm firmly clamped in the valve casing, 5 firmly connected to a valve body and separating two control chambers from one another in which one control chamber is connected via an auxiliary valve with a chamber adapted to be connected to the pipe system supplying the operating vacuum and is provided with one or more lO calibrated air inlets and the other control chamber is connected to atmospheric air through a filter.

2. A valve as claimed in claim 1 in which the auxiliary valve has means for adjusting the operating vacuum in the one control chamber. 15

3. A valve as claimed in claim 2 in which the auxiliary valve is acted upon by a second diaphragm assembly opposite sides of which are exposed respectively to atmospheric air and in use to the pipe system.

4. A valve as claimed in claim 3 including 20 biassing means biassing the auxiliary valve in the closing direction.

5. A valve assembly for automatically regulating tho operating vacuum in milking systems substantially as described herein with reference to and as shown in the 25 accompanying drawings. K. K. KKI.I.Y & CO., ACKNTS l-MR TIIK AHI'l. I CANTS. - 8 -