US2359508A - Pulsator, and more particularly pulsator for milking machines - Google Patents

Description

Oct. 3, 1944. K.'A. BERGSTEDT 2,359,508

PULSATOR, AND MORE PARTICULARLY PULSATORS FOR MILKING' MACHINES F iled March 19, 1941 Patented Oct. 3, 1944 PULSATOR, AND MORE PARTICULARLY PULSATOR FOR MILKING MACHINES Karl Abdon Bergstedt, Lindesberg, Sweden Application March 19, 1941, Serial No. 384,175 In Sweden February 17, 1940 8 Claims.

The present invention refers to improvements in pulsators, and more particularly pulsators for milking-machines.

The principal object of the invention is to provide a pulsator the movements of which are both distinct and independent of the variable volume of the conduits connected to the pulsator. Other objects will appear as the description proceeds.

The improved pulsator according to the invention will be described on the assumption that it is intended for use in connection with milkingmachines, but this does not mean that the invention is inapplicable to pulsators intended for other purposes, and the invention is therefore not to be considered limited to milking-machine pulsators.

Generally, in milking-machines the pulsator serves to put a number of conduits connected with teat cups or the like into communication alternately with a source of vacuum and with the atmosphere. The improved pulsator according to the invention is of the type in which the movable parts are driven by two diaphragms which produce the governing movements of the pulsator by being subjected alternately to vacuum and pressure. Of the two diaphragms one has a greater active surface than the other, and both diaphragms co-operate with a valve slide either directly or indirectly by the intermediary of a suitable motion-transmitting member. According to the invention, each of the diaphragms on both sides borders on rooms or chambers which by passages communicate in such manner with passages or grooves provided in the valve slide that said chambers are alternately put into communication with the source of vacuum and with the atmosphere, one diaphragm (the larger one) determining the main movement and the frequency of alternations of the slide at the reciprocation thereof, while the other diaphragm (the smaller one) serves to complete and accelerate the movement of the slide when passing an intermediate cut-ofi position which will be referred to as the central position in the following.

The invention may be embodied substantially in two forms. In one of them both diaphragrns are rigidly connected with the valve slide, and in the other only the smaller diaphragm is rigidly connected with the slide, while the larger one actuates the slide through an intermediate member Which permits a certain free or idle motion or play of the diaphragm relative to the slide in the direction of movement thereof. In the case of longitudinally displaceable valve slides this intermediate member may. preferably consist of a spindle passing through and displaceable in the slide in the direction of displacement thereof, said spindle actuating the slide by means of suitably provided abutments.

In this connection it should also be noted that the invention is not limited exclusively to longitudinally displaceable slides, although these are preferred because of the resultant constructional simplicity.

In the following the invention will be described with reference to the accompanying drawing which diagrammatically shows two forms thereof in longitudinal section and in which:

Figure 1 shows a form in which both diaphragms are directly connected with the valve slide, and

Figure 2 shows a form in which only the smaller diaphragm is directly connected with the slide, while the larger diaphragm is arranged to actuate the slide through an intermediary member.

In both figures, the same reference numerals are used to designate similar parts.

It should be noted that both figures show the valve slide in the central position defined above which is highly unlikely when the pulsator is at rest, but if the slide should stop in this position, the pulsator may easily be started again by giving the slide a slight push or by rapidly moving the pulsator axially, so that the slide will be slightlydisplaced owing to the action of inertia.

The invention may be most simply described by reference to the operation of the pulsator, which is substantially the same for both disclosed forms thereof. It will be assumed that the slide I initially is a little to the right of the central position shown in the drawing.

The vacuum will then be rapidly transmitted through the conduit 4 communicating with the source of vacuum and the passage I l to the chamber I2 on the outside of the smaller diaphragm 8, both diaphragms being moved to the right, taking the slide 1 along the full valve opening. This connection is established through the intermediate Valve groove in the slide 1, the passage 1 I and the branch passage connected thereto and leading to the above-mentioned chamber. The passage II is also connected to the chamber it on the outside of the larger diaphragm 9, through the intermediary of a throttle valve I5 (needle valve or the like) which by suitable adjustment determines the time taken for the transmission of the vacuum to chamber I l. The position of this valve accordingly determines the frequency of the pulsations per unit of time.

Gradually, however, the vacuum will be transmitted also to chamber I4, and as it approaches the same value as that in chamber I2, the diaphragm 9 will be drawn to the left due to its greater area. Thereby the atmospheric air will be given entrance to the chamber I2 through axial channel I6 in Fig. 1 (or channel means 6 in Fig. 2), the rightmost valve groove in the. slide and the channel ll, whereas a vacuum is simultaneously created in the chamber l3 transmitted through the middlemost valve groove in the slide and the channel I0. As the chamber I4, due to the throttle means I5, is still under vacuum, the slide will be rapidly thrown over into its leftmost end position. The atmospheric air will gradually enter the chamber I4 through the throttle means I5, however, whereby the diaphragm system will begin to move to the right under influence of the vacuum within the chamber l3. Thereafter the same course of functioning will be repeated but in the reversed direction. Hence the slide will be moved forwards and backwards with a rapidity determined by the adjustment of the throttle means.

It is to be noted that for exact function it is required that the inlet openings to the passages II] and II as seen in the axial direction should have a greater dimension than the corresponding openings to the passages 2 and 3 which are assumed to lead to the teat cups of the. milkingmachine, so that the passages I and II are uncovered one moment before the passages 2 and 3. Naturally, the same result could also be attained with passage openings having equal axial dimensions, if the'valve grooves in the slide are made such as to converge toward the passages l0 and II.

The form according to Figure 2 difiers from that shown in Figure 1 only in the respect that the largeridiaphragm 9 is not directly connected with the slide I but with a spindle II axially displaceable through the latter, screw means for securing the diaphragm to said spindle serving as an abutment to the slide in one direction and a flange l8 provided at the free end of the spindle serving as an abutment in the other direction of movement. The function is the same as described above, but the diaphragm 9 is given a slightly delayed action on the movement of the valve slide, and thereby more distinctly marked slide movements are obtained.

In both forms the slide 1 or I is assumed to be round and displaceably mounted in a boring lined with a sealing bushing in a surrounding housing I. However, the slide may also be flat or have practically any cross section, the construction or form of the housing being or no importance to the invention; it can be varied as required Besides serving as a timing throttle valve the valve I may also be used to bring the pulsator into andout of operation, and by correct attendance on this valve at the stopping of the pulsator, it may also be ensured that the slide will not stop in the central position, so that the pulsator will againstart without further ado when the valve is opened. 7

In the foregoing it was suggested that the conduits 2 and 3 may be assumed'connected to the teat cups of the milking-machine, and according to the number of teat cups connected, the number of such conduits may of course vary, if desired by branches from one conduit. 'During its recipro nected to thepassages l0 and II, but such a construction is unsuitable, for in that case both these conduits as a whole and teat cups, etc., connected thereto, which may contain much air and are of a non-predetermined volume, must be filled and emptied before the pressure differences in the chambers bounded by the diaphragms can have any influence on the function of the pulsator. It is for this reason that both the teat cup conduits and the supply conduits for atmospheric air have been provided with inlet openings separate from the passages It and II, and in the constructions shown in the drawing it is of importance that the inlet openings of the passages I0 and l I should have the same dimension in the axial direction as the sealing intermediate portions of the slide between the groove-shaped valve channels therein, while the openings of the passages 2 and 3 have a smaller axial dimension.

Thereby the inlets to the passages I0, II will be'uncovered as the slide passes the central po-.

sition one moment before the inlets to the passages 2 and 3, so that the pressures or vacua, respectively, have time to betransmitted to the diaphragm chambers before any pressure reduction is produced through the conduits 2 and 3 which causes the slide to be reversed rapidly and with certainty irrespective of the volume of the conduits 2 and 3 and the cavities connected thereto.

What I claim and desire to secure by Letters Patent is:

l. A pulsator, comprising a housing, valve means movable in said housing, two diaphragms having flexible portions of different size mounted within said housing and dividing it into three chambers, said diaphragms being bperatively connected with said valve means, passages connecting said valve means with the chambers in said housing, a restriction in the passage leading to one of the chambers bounded by the diaphragm with the larger flexible portion, conduits leading from said housing to an outside vacuum source and to outside vacuum consumers, respectively, and a passage connecting said valve 5 means with the atmosphere.

2. A pulsator, comprising a housing, valve means movable in said housing, two diaphragms having flexible portions of different size mounted within said housing and dividing it into three chambers, said diaphragms being rigidly con nected with said valve means, passages connect-- having flexible portions of different size mounted within said housing and dividing it into three chambers, one of said diaphragms being rigidly connected with said valve means and the other being connected with said valve means with some play, passages connecting said valve means with thechambers in said housing, a restriction in the passage leading to one of the chambers bounded by the diaphragm with the larger flexible portion, conduits leading from said housing to an outside vacuum source and to outside vacuum consumers, respectively, and passages connecting said valve means with the atmosphere.

4. A pulsator, comprising a housing, valve,

means movable in said housing, two diaphragms having flexible portions of different size mounted within said housing and dividing it into three chambers, the smaller diaphragm being rigidly connected with said valve means and the larger diaphragm being connected with said valve means with some play, passages connecting said valve means with the chambers in said housing, a restriction in the passage leading to one of the chambers bounded by the diaphragm with the larger flexible portion, conduits leading from said housing to an outside vacuum source and to outside vacuum consumers, respectively, and passages connecting said valve means with the atmosphere. r

5. A pulsator, comprising a housing, valve means movable in said housing, two diaphragms having flexible portions of different size mounted adjacent each other within said housing and dividing it into two chambers bounded each by one of the diaphragm portions and one intermediate chamber bounded by both diaphragm portions, said diaphragms being operatively connected with said valve means, passages connecting said valve means with the chambers in said housing, a restriction in the passage leading to the chamber bounded by the larger diaphragm portion only, conduits leading from said housing to an outside vacuum source and to outside vacuum consumers, respectively, and a passage connecting said valve means with the atmosphere.

6. A pulsator, comprising a housing, valve means movable in said housing, two diaphragms having flexible portions of difierent size mounted within said housing and dividing it into three chambers, said diaphragms being operatively connected with said valve means, passages connecting said valve means with the chambers in said housing, throttle means inserted in the passage leading to one of the chambers bounded by the diaphragm with the larger flexible portion, conduits leading from said housing to an outside vacuum source and to outside vacuum consumers, respectively, and a passage connecting said valve means with the atmosphere.

7. A pulsator, comprising a housing, valve means movable in said housing,'two diaphragms having flexible portions of different size mounted within said housing and dividing it into three chambers, said diaphragms being operatively connected with said valve means, passages connecting said valve means with the chambers in said housing, an adjustable throttle valve needle inserted in the passage leading to one of the chambers bounded by the diaphragm with the larger flexible portion, conduits leading from said housing to an outside vacuum source and to outside vacuum consumers, respectively, and a passage connecting said valve means with the atmosphere 8. A pulsator, comprising a housing, valve means movable in said housing, two diaphragms having flexible portions of different size mounted within said housing and dividing it into three chambers, said diaphragms being operatively connected with said valve means, passages ending in the chambers in said housing, valve openings in said housing co-operating with said valve means and forming terminals of said passages, a restrictionin the passage leading to one of the chambers bounded by the diaphragm with the larger flexible portion, conduits leading from said housing to an outside vacuum source and to outside vacuum consumers, respectively, valve openings in said housing co-operating with said valve means and forming the inner terminals of the conduits leading to the vacuum consumers, the lastmentioned valve openings having a width relative to the width of the firstmentioned valve openings such as to be later uncovered and earlier covered by said valve means at the movement thereof than the latter openings, and a passage connecting said valve means with the atmosphere.

KARL ABDON BERGS'I'EDT.

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