GB2156048A

GB2156048A - An apparatus for transporting equal quantities of liquid to a number of users of the same kind

Info

Publication number: GB2156048A
Application number: GB08506737A
Authority: GB
Inventors: Dr Heinz Schippers
Original assignee: Barmag Barmer Maschinenfabrik AG
Current assignee: Oerlikon Barmag AG
Priority date: 1984-03-15
Filing date: 1985-03-15
Publication date: 1985-10-02
Also published as: FR2561317A1; GB8506737D0; IT1185533B; FR2561317B3; IT8519823A0

Abstract

An apparatus for the continuous distribution of equal quantities of liquid to a number of users of the same kind consists of a metering or measuring pump (1) transporting a constant or adjustable flow which passes a distributor device (3) and the distributor conduits (6) to the users. The distributor device consists of a pot-shaped pressure chamber (8), which is sealed by a cover (5) with the connections of the distributor conduits (6) distributed on the circumference. In the pressure chamber (8) a distributor disc (9) rotates on a driving shaft (14) driven from the outside and passing into the pressure chamber (8) in a pressure-sealed manner. The distributor disc (9) has at least one valve bore (15) on a radius which corresponds with the radius of a circle of outlet bores (13) in the cover (5). The distributor disc (4) is positioned on the driving shaft (14) in an axially shiftable manner and it is pressed against the ring-shaped thickening (17) on the cover (5), in which the outlet bores (13) are positioned, by a resilient means (27). Particular measures are taken regarding the formation of the valve bore (15) for preventing water hammers. <IMAGE>

Description

SPECIFICATION An apparatus for transporting equal quantities of liquid to users of the same kind.

This invention relates to an apparatus for transporting equal quantities of liquid to a number of users of the same kind.

Where a relatively large number of users of the same kind at equal distances are to be provided with a liquid, reciprocating or plunger pumps are used, in which, for example, the individual pistons are positioned on the circumference of a swash plate which drives them. plunger pumps, however, demand substantial expenditure owing to the necessary high finishing accuracy and are very susceptible to distrubances especially when transporting liquids with a low or no lubricating effect.

An object of the invention is to provide a simple, inexpensive and uncomplicated apparatus which can provide a large number of users with identical flows of liquid with high operational reliability.

According to the invention there is provided an apparatus for transporting equal quantities of liquid to a number of users of the same kind, wherein the apparatus is formed as a distributor which has a pressure chamber connected via a connecting conduit to a source of liquid, a face of which pressure chamber has a number of outlet bores positioned on a circle and corresponding to the number of distributor conduits, and in which a distributor disc is provided which is rotatable from the outside and is pressed in a sealed manner against the said face with the orifices of the outlet bores, the disc axis having its axis passing thrcugh the central point of the said circle and having at least one valve bore located opposite the said circle.

In a preferred embodiment the source of liquid is a metering or measuring pump which continuously transports a constant, preferably adjustable quantity. The distributor takes over the distribution of the flow of liquid which is preferably under constant, regulated pressure, to the individual users of the same kind. As already mentioned, the distributor has a pressure chamber, and the pump conduit discharges into this. The orifices of the distributor conduits are positioned on a circle on a plane wall of the pressure chamber. The distributor disc is pressed against this wall, and is driven at a constant rotational speed. The distributor disc has at least one hole on a hole circle, which has the same radius as the abovementioned circle and is positioned concentrically to the axis of revolution of the perforated disc.The number of holes in the perforated disc preferably does not correspond to the number of users. By rotation of the distributor disc, the users are provided with a quantity of liquid which is substantially determined by the quotient of the quantity of liquid transported during each complete revolution of the distributor disc and the number of users.The distributor advantageously consists of a pressure chamber, which is preferably a substantially circular cylindrical pressure chamber, positioned above a connecting conduit connecting to the pump, the face of which pressurised chamber has a number of outlet bores running in an axial manner and positioned on a hole circle, and corresponding to the number of distributor conduits; in the pressure chamber a distributor disc is provided which can be rotated from the cutside, and is pressed in a sealed manner against the inside of the face provided with inlet orifices, the axis of which distributor disc runs through the central point of the hole circle and has at least one valve bore opposite the hole circle.

The pressure chamber is advantageously in the shape of a circular cylindrical pot and its cylinder axis coincides with the axis of the distributor disc. It is sealed by a lid into which the outlet bores are arranged on a circle concentric to the pressurised chamber axis and arranged in a parallel manner to this. The pressure chamber is advantageously connected to a pressure equalization chamber, for example an air chamber, by means of which the pressure fluctuations arising from the intermittent operation can be substantially compensated for.

Embodiments of the invention are described in more detail below with reference to the accompanying drawings, in which: Fig. 1 is an embodiment of an apparatus according to the invention, partially sectioned; Fig. 2 shows different forms of the valve bore; Fig. 3 to 5 show the inside of the distributor cover with different positioning of the valve bores and orifices.

As shown in Fig. 1, a pressure conduit 2 leads from a metering or measuring pump 1, preferably of a construction such that its transporting performance is relatively independent of the back pressure, to a distributor 3 which has the task of evenly distributing the quantity of liquid continuously supplied from the measuring pump 1 to the connected users. The transporting performance of the pump 1 is adaptable to the requirements of the users, which is possible, for example in the case of a positive-displacement pump, by changing the driving rotational speed.

The distributor 3 consists of a pot-like body which is sealed at the top by a cover 5. Outlet bores 13, running parallel to the axis and evenly distributed on a circle of holes 18, are introduced into this body, the outlet bores can normally be cylindrical, but can be advantageously extended towards the outside in a conical manner in the case of a very narrow diameter 23. It is advantageous, as shown in the drawing, if the outlet orifices do not terminate on the inner face 12 of the cover 5, but terminate in knobs placed on these outlet orifices or in a ring-shaped thickening 17, the surface of which is carefully machined.

A distributor disc 9 is provided inside the distributor 3. It is rotatable and its driving shaft 14 passes through the central point of the circle of holes 1 8. It is driven by a motor 4 with which it is connected by a coupling 10. It is positioned on its shaft such that it can be shifted longitudinally, so that it can be pressed against the surface of the ring-shaped thickening 1 7 or the knobs 1 7 by means of the pressure spring 27. The distributor disc 9 has at least one valve bore 15, the spacing of which from the axis 14 thereof corresponds to the radius 1 6 of the circle of holes 18.

The interior 8 of the distributor is connected to a pressure equalisation chamber 7, in which an air cushion intercepts pressure fluctuations via the liquid level, which fluctuations can only be prevented during operation of the distributor with only one valve bore 1 5 in the distributor disc 9, with particular precautions.

The equalisation chamber 7 is connected to the pressurised chamber 8 via a conduit 26.

In a very simple embodiment, the distributor disc 9 has only one valve bore 1 5. It has a round cross-section and the diameter is as large as the orifice 11. The result can thus be achieved that a discontinuous flow of liquid, which remains substantially constant with time leaves the pressurised chamber 8 of the distributor 3 and is passed via the distributor conduits 6 to the users. There are different possibilities for the formation and number of valve bores. Thus an elongate hole 1 9 is represented as valve bore 1 5 in the left-hand region of Fig. 2, which bore renders possible, using only one valve bore 1 5 in the distributor disc 9, a flow of liquid from the pressurised chamber 8 which remains substantially constant in sum total, thus preventing pressure fluctuations.If the elongate hole 1 9 attains a total length 21 which is equal to the spacing 24 between adjacent orifices 11, the following orifice 11 in each case is opened during further movement of the distributor disc to the extent that the previous one is sealed. The width of the elongate hole 1 9 running in a curve corresponding to the circle of holes 18, advantageously corresponds to the diameter 23 of the orifice 11. The elongate hole 1 9 can be rounded at its ends, as shown, with a radius corresponding to the orifice 11, or it can be provided with straight walls at its end which run, for example, in the direction of the radius 1 6 of the circle of holes.

A further possibility for maintaining a substantially constant flow from the pressurised chamber 8 of the distributor 3, is produced by the arrangement shown in the middle representation of Fig. 2 taken in conjunction with Fig. 4 where an uneven number of outlet bores 1 3 are provided on the circle of holes 18. The centre spacing 24 of adjacent orifices 11 is about equal to double the diameter 23 of the orifices 11, and the diameter of the valve bores 1 5 is equal to half the centre spacing 24. An even number of valve bores 15, at least two, is provided. The valve bores 1 5 are in each case positioned opposite each other on a hole circle diameter.The extent to which the valve bores are covered are thereby extended with the orifices 11 of the outlet bores 1 3 to an cutlet cross-section remaining, in each case, substantially equal. As Fig. 2 (right) and Fig. 5 show, the valve bores positioned opposite each other can also be formed as elongate holes, the centres of which are positioned opposite each other on a hole circle diameter and the extent to which the valve bores are covered but with orifices of the outlet bores being such that the total outlet cross-section remains almost constant. The width 20 of the elongate hole corresponds to the diameter of the orifices 11 and the length thereof 21 corresponds to half the spacing 24 of the neighbouring orifices 11.

Fig. 3 shows the inside 1 2 of the distributor cover 5, on which in a further development of the invention either the knobs 1 7 (side A) or a ring-shaped thickening 1 7 (side B) passing through, are provided. A substantial reduction in the supporting surface for the distributor disc is thereby achieved, whereby, for a given force of the pressure springs 27, a substantially higher surface pressure is achieved and thus an improvement in the sealing effect between the distributor disc 9 and the orifices 11 of the distributor conduits 6.

It is to be noted that cases can arise in which the provision of a pressure reducing device 22 between the measuring pump 1 and the distributor 3 in the connecting conduit 2 can be necessary or useful, in order to ensure a constant pressure in the pressure chamber.

It is also to be noted that a pressure equalisation bore 28 is provided in the distributor disc 9, when the cover 5 has a ring-shaped enlargement 1 7 formed in its peripheral region, as in Fig. 3, side B, and the distributor disc 9 is pressed in a sealed manner against the polished surface of the enlargement with the outlet bores 1 3. The result is thus achieved that the pressure of the valve disc on the enlargement 1 7 is adjustable in a pressure-independent manner only by preselection of the springs and the prestressing force thereof.

The pressure equalisation bore 28 can be provided at any position on the distributor disc 9, so that a connection between the pressurised chamber 8 and the lower side of the lid 5 is produced. The thickening 1 7 forms a disc-shaped hollow chamber on this lower side. These pressure equalisation bores 28 are marked in Figs. 4 and 5.

Figs. 4 and 5 show a view of the distributor disc 9 in a section through the distributor.

The distributor disc 9 has the two valve bores 15, which are diametrically opposite each other. The valve orifices 11 of the distributor cover 5 are shown in broken lines. The spacing 24 between the centres of adjacent orifices 11 and the diameters of these orifices 11 are selected such that the gap between adjacent orifices is substantially equal to the diameter of the valve bore 1 5. Moreover, the angular distance between the orifices 11 is selected such that the number of orifices 11 is odd. The result is thus achieved that the two valve bores 1 5 always ensure a substantially even total outflow from the pressurised chamber 8.Should one of the valve bores 1 5 (left in Fig. 4) be completely sealed, the other valve bore 1 5 (right in Fig. 4) completely covers an orifice 11 of the outlet bore 1 3. If the distributor disc 9 is rotated further, the extent to which the left-hand valve bore 1 5 is covered by the orifice 11 of the following outlet bore 1 3 increases, while the extent to which the right-hand valve bore 1 5 is covered by the orifice 11 decreases.

Fig. 5 likewise shows the bottom view of the distributor disc 9 in a section through the distributor. The orifices of the distributor cover 5 are again indicated by a broken line. The number of orifices is odd. The distributor disc has two valve bores 15, which are diametrically opposite each other. As is also shown in Fig. 2, right-hand side, the valve bores 1 5 are represented as elongate holes. The hole length 21 exactly corresponds to the spacing of two orifices 11, that is the hole length is equal to the spacing 24 between adjacent orifices 11 minus the diameter of an orifice 11. By co-ordinating the hole length 21 with the spacing 24, a substantially even outflow from the distributor 3 can be effected, so that water hammers are prevented.

In another embodiment of the distributor apparatus according to Fig. 1, the metering or measuring pump is connected via the connecting conduit 2, or directly via the pump outlet, to the pressure equalisation chamber 7, so that pressure fluctuations are substantially cushioned and the liquid present in the pressure equalisation chamber 7 is continuously exchanged and rinsing of this chamber takes place.

It is also within the scope of the invention for the metering or measuring pump 1 to be accommodated in the pot-shaped pressurised chamber 8 of the distributor 3 and the pump and the distributor disc 9 to be preferably driven by a common shaft 1 4. In this case the drive mechanism 4 is preferably an electromotor which has a reducing gear system having an adjustable rotational speed and forms the common drive mechanism.

The basic characteristic of the apparatus described above according to the invention is that the distribution of the flow of liquid in individual liquid flows and the metering of this liquid flow takes place by a single apparatus, and that the metering does not take place by throttling, as has been usual so far, but according to the interruption principle. The interruption principle has the advantage over throttling that in the case of small quantities of liquid, it does not give rise to operational loss and is substantially more precise.

Claims

1. An apparatus for transporting equal quantities of liquid to a number of users of the same kind, wherein the apparatus is formed as a distributor which has a pressure chamber connected via a connecting conduit to a source of liquid, a face of which pressure chamber has a number of outlet bores positioned on a circle and corresponding to the number of distributor conduits and in which a distributor disc is provided which is rotatable from the outside and is pressed in a sealed manner against the said face with the orifices of the outlet bores, the disc having its axis passing through the central point of the said circle and having at least one valve bore located opposite the said circle.

2. An apparatus according to claim 1, wherein the pressure chamber, the longitudinal axis of which coincides with the axis of rotation of the distributor disc, has a circular, cylindrical pot-shape, and the pressure chamber is sealed by a cover in which the outlet bores are positioned on said circle, said circle being concentric to the pressure chamber axis and the bores being positioned parallel to its said axis.

3. An apparatus according to either preceding claim, wherein the pressure chamber of the distributor is connected via a conduit to a pressure equalisation chamber.

4. An apparatus according to claim 3, wherein the pressure equalisation chamber is formed as an air chamber.

5. An apparatus according to any preceding claim, wherein the outlet bores leading to the distributor conduits extend conically towards the outside.

6. An apparatus according to claim 2, or any one of claims 3 to 5 as dependent on claim 2, wherein the cover having the outlet bores has a thickening on the said face thereof on which thickening the orifices of the outlet bores are positioned and against which the distributor disc is pressed in a sealed manner.

7. An apparatus according to any preceding claim, wherein the valve bore in the distributor disc has a round cross-section with a diameter which substantially corresponds to the diameter of the outlet bores.

8. An apparatus according to any one of claims 1 to 6, wherein the valve bore in the distributor disc is an elongate hole extending on the circumference of a circle which is congruent to the circle of the outlet bores, the length of said elongate hole being approximately equal to the centre-to-centre spacing of adjacent outlet bores on the circle of outlet bores.

9. An apparatus according to any preceding claim, wherein two or more valve bores are positioned on a circle coinciding with the circle of outlet bores, and are distributed equidistantly therealong.

10. An apparatus according to claim 9, wherein the number of outlet bores positioned on the circle of outlet bores is an odd number and the distributor disc has two valve bores which are diametrically opposite each other.

11. An apparatus according to claim 10, wherein the free space between adjacent outlet bores is at least equal to the diameter of the orifices thereof and the hole length of the valve bore corresponds to half the centre-tocentre spacing of adjacent orifices

1 2. An apparatus according to any preceding claim, wherein the outlet bores or the distributor conduits are provided with backflow stop devices or non-return valves.

1 3. An apparatus according to any preceding claim, wherein a pressure reducing device is provided between the metering pump and the distributor.

14. An apparatus according to any preceding claim, wherein the distributor disc has a pressure equalisation bore.

1 5. An apparatus according to any preceding claim, wherein the distributor disc with the valve bore(s) is axially movable on a shaft driven by a motor and is pressed by a force means against the said face.

1 6. An apparatus for transporting equal quantities of liquid, substantially as herein described with reference to any of the embodiments shown in the accompanying drawings.