GB2114906A

GB2114906A - Mixing and dispensing liquids

Info

Publication number: GB2114906A
Application number: GB08301946A
Authority: GB
Inventors: John L Carpenter
Original assignee: Individual
Current assignee: Individual
Priority date: 1982-01-26
Filing date: 1983-01-25
Publication date: 1983-09-01
Also published as: GB8301946D0

Abstract

Apparatus comprises a first container 10 for a first liquid and a second container 12 for a second liquid, the bases of the containers being in open communication, in use. A common outlet 14 is arranged to receive and dispense a mixture of the first and second liquids from the first and second containers. The first and second liquids enter the common outlet 14 in pre-determined proportions, with the proportions being determined at any particular time by the respective surface areas of the first and second liquids in the two containers at that time. <IMAGE>

Description

SPECIFICATION Mixing apparatus This invention concerns mixing or dispensing apparatus.

Dispensing systems, which may include service outlets known as nipple drinkers or other appropriate outlets, are commonly used in animal farming to dispense drinking water containing predetermined quantities of liquid medicaments to livestock, for example piglets. One such dispenser comprises a tank containing the solution of the water and the liquid medicaments and haying an outlet supplying a plurality of nipples from which the livestock can draw the solution on demand.

Measured quantities of the water and the medicaments are periodically added to the tank when it needs replenishing.

The present invention provides mixing apparatus which is arranged to supply two liquids mixed in pre-determined proportions and which is adapted to maintain the mixture in desired proportions, whether supply is intermittent or continuous.

In accordance with the invention, there is provided apparatus for supplying a liquid mixture, comprising a first container for a first liquid, a second container for a second liquid, and a common outlet for receiving and supplying the liquids from the first and second containers, the arrangement being such that the first and second liquids enter the common outlet in pre-determined proportions, the pre-determined proportions being determined at any particular time by the respective surface areas of the first and second liquids in the first and second containers at that time.

For example, during normal operation, the base of the first container may be arranged to communicate freely with the base of the second container by way of a connector to which the common outlet is joined. Then, if the two liquids have the same specific gravity, their levels will fall at the same rate during dispensing. Even if they have different specific gravities, their levels will fall at respective pre-determined rates. In each case, the proportions of the two liquids in the mixture may be determined by the relative surface areas of the liquids and their relative specific gravities.

The invention also features apparatus for dispensing a mixture of liquids from two supplies, including means for automatically recharging one or both of the supplies as and when necessary.

Another aspect of the invention resides in the provision of a metering arrangement by which the volume of the mixture discharged can be established.

Preferably, the metering arrangement comprises means for counting the number of cycles during which one at least of the supplies empties and is replenished, and means for indicating the volumes of the two liquids either remaining at any moment in a particular cycle or already dispensed at the time.

The invention is described further, by way of example, with reference to the accompanying drawings in which: Figures 1 a to 1 c illustrate a first embodiment of dispensing apparatus according to the invention in various conditions; Figure 2 shows a further embodiment of dispensing apparatus; Figures 3 and 3a show a modification of the dispensing apparatus of Figure 1; and Figures 4 and 4a show a modification of the dispensing apparatus of Figure 2.

Referring initially to Figures 1 a to 1 c, dispensing apparatus according to the invention comprises a first, relatively large, container 10 and a second, relatively small, container 12. The containers 10 and 12 are situated adjacent to one another in side by side relation and have their bases substantially level with one another. A connector 1 4 joins the base of the container 10 to the base of the container 12 and communicates the two containers with a common outlet 1 6. The connector 1 4 is a self-sealing quick-release hydraulic coupling. Normally, the base of the container 10 and the base of the container 12 are in open communication with one another by way of the connector 14, and the two containers communicate freely with the common outlet 1 6 accordingly.

Thus, when the container 10 is filled with water and the container 12 is filled with a liquid medicament, a mixture of the two forms in the outlet 1 6. A swirl unit 18 is provided in the outlet 1 6 to assist in the mixing process. The liquid medicament dissolves in the water and a solution is generated which is supplied by the outlet 16, which may be connected to a conventional nondrip nipple drinker to enable the solution to be dispensed intermittently or continuously on demand.

Assuming that the water and the liquid medicament have the same specific gravity, the absolute levels of these in the two containers 10, 12 will at all times tend to be the same.

Accordingly, providing that the container 10 and the container 12 are initially filled so that no liquid flow occurs between the two, it follows that the volumes of the two liquids supplied into the common outlet 1 6 will be in pre-determined proportions and these pre-determined proportions will at any moment depend on the respective surface areas of the liquids in the containers 10 and 12 at that moment.

The operation of the apparatus shown in Figures 1 a to 1 c, and its variations illustrated in Figures 2 to 4, is based on a recognition of this.

More specifically, in Figure 1 a, the container 10 is filled with water to a pre-determined level within the container 10 and the container 1 2 is filled with liquid medicament to a pre-determined level within the container 1 2. In absolute terms, these levels are the same. As solution is withdrawn from the common outlet 16, these levels drop. The containers 10 and 1 2 are open to atmosphere, and so nothing counteracts the ebb of the two liquids.

Initially, as the liquid levels fall, an auxiliary container 22 mounted within the container 10 on one of its side walls remains full. The auxiliary container 22 is spaced above the base of the container 10 substantially on a level with a supply valve 24 for supplying water from a mains supply pipe 26 into the upper end of the container 10. A ball float 28 received within the auxiliary container 22 is connected to the supply valve 24 by way of a control arm 30 and controls the supply valve 24 in dependence upon the orientation of the arm 30.

When the auxiliary container 22 is full, the ball float 28 floats at such a height that the control arm 30 is horizontal, and in this condition of the arm 30 the supply valve 24 remains closed.

Thus, whilst the water and liquid medicament are dispensed, the supply valve 24 is maintained in a closed condition to prevent further water from entering the container 10, as shown in Figure 1 b.

The container 12 has no external supply but is replaceable. It is releasably supported above the connector 14, with the aid of a support 20.

When the water in the container 10 falls below a pre-determined level as illustrated in Figure 1 c, a control float 32 drops to open a valve 34 in the base of the auxiliary container 22. The container 22 now discharges into the container 10 and the ball float 28 descends, carrying the control arm 30 with it. This opens the supply valve 34 to allow mains water into the container 10 for replenishing it.

The rising level of the water in the container 10 lifts the control float 32 to shut the valve 34 in the base of the auxiliary container 22. Subsequently, the water in the container 10 reaches such a level that it flows over the walls of the auxiliary container 22 to refill this container. This once again lifts the ball float 28 (see Figure 1 a) to close the valve 24.

Before the cycle can repeat, the original container 12 must now be replaced with a new container filled with liquid medicament.

Also shown in Figures 1 a to 1 c, are a volume compensating block 36 mounted within the container 10. This block acts as a corrector for ensuring a desired volume ratio of the liquids forming the solution in the common outlet 16, in the event that the dimensions of the container 10 and 1 2 do not exactly suit the desired result.

Additionally, the mains supply pipe 26 is formed with a connector 38 for plugging in to an appropriate connector in a mains supply line.

Turning now to Figure 2, another embodiment of dispensing apparatus is illustrated. The second embodiment includes some of the same features as the first embodiment and like parts are designated by the same reference numerals. In this case, however, control of the supply of mains water to the container 10 from the mains supply pipe 26 is not purely hydraulic but is additionally by way of an electrically operated valve.

As before, the apparatus includes a supply valve 24 operable by a ball float 28 through a control arm 30. The supply valve 24, however, constitutes only a first supply valve. A second supply valve 40, which is a solenoid valve, is also provided upstream of the valve 24 in the supply pipe 26. The arrangement of the two valves 24, 40 is such that the valve 40 is normally closed and opens for a pre-determined period for permitting a flow of water into the container 10, and the valve 24 is normally open but is made to close before the end of this pre-determined period to terminate the flow of water once it has reached a predetermined level in the container 1 0.

In particular, as container 10 fills, the ball float 28 rises until it lifts the arm 30 to shut off the valve 24. A few moments later, the valve 40 also closes.

In the dispensing process which follows, the ball float 28 descends and opens the valve 24 but mains water is prevented from reaching this valve by the valve 40. When the water level approaches the bottom of the container 10, a further float to 42 lowers, and a signalling device 44 connected to the float 42 issues an electrical control signal.

An electronic control circuit 46 senses the control signal and opens the valve 40 so that the container 10 is recharged. The circuit 46 includes a timing arrangement for control of the timing of the valve 40 precisely, and it remains open for a pre-determined period and no longer.

Figures 3 and 3a illustrate a variation on the apparatus of Figures la to 1 c. Similar parts are identified by the same reference numerals.

The differences present in the Figure 3 embodiment are two-fold: Firstly, the container 1 2 is rechargeable; and secondly, the apparatus includes a metering arrangement for use in determining the total volume dispensed at any time.

To enable the container 1 2 to be recharged, a reservoir 48 is mounted above it and is connected to the upper end of the container 12 by way of a medicament supply pipe 50. A valve 52 in the supply pipe 50 controls the quantity of medicament supplied to the container 1 2 and, for this purpose, is connected by a control arm 54 to the control arm 30 which is attached to the ball float 28 (see Figure 3a). Consequently, the valve 52 opens and closes in synchronism with the valve 24.

A valve 52 is situated at an absolute level corresponding with the maximum level reached by the water in the container 1 0. Thus, when the valve 52 closes, it ensures that the height of the medicament in the container 12 corresponds with that of the water in the container 10.

An automatic air-bleed valve located just below the medicament supply valve 52 allows air to enter the container 12 during dispensing and to leave the container 12 during recharging.

The metering arrangement featured in the embodiment of Figures 3 and 3a comprises a mechanical counter 58 having a depending trip rod 60 which extends towards the float operated control arm 30. The trip rod 60 terminates in a shoe 62 situated in the vertical path of the arm 30. On each occasion that the arm 30 rises, it lifts the shoe 62 to increment the count the counter 58 by a count of 1.

Additionally, the metering arrangement includes a volumetric scale 64 on the side wall of the container 12. The container 1 2 is transparent and thus the volume of liquid which has been dispensed from it at any moment can be determined from the scale 64. Correspondingly, the volume of liquid which has been dispensed from the container 10 can be established, since the relative surface areas of the two liquids being dispensed are pre-determined and since both liquids have fallen by the same amount.

The total volume dispensed can be cornputed by multiplying the count within the counter 58 by the total dispensing volume of the containers 10 and 12, and adding the result to the volume dispensed in the particular cycle as determined from the scale 64.

Finally, Figures 4 and 4a show a modification of the embodiment of Figure 2. Similar parts are designated by the same reference numerals.

The Figure 4 embodiment resembles the Figure 3 embodiment in that the container 12 is rechargeable and a metering arrangement is provided, In this instance, the valve 52 is replaced by an additional valve 66 operable by the control circuit 46 to open and close in synchronism with the valve 40 in the mains supply pipe 26. The valve 66 is aligned with the maximum level of the water in the container 10 and so, although it closes after the container 10 has completely filled, this does not matter. Once the valve 66 has closed, it ensures that the upper level of the medicament in the container 12 corresponds with the level of the water in the container 10.

A bleed valve 56 is again provided to admit air to and allow air to escape from the container 12, thus preventing any undesired pressure build-up or reduction in this container.

In the Figure 4 embodiment, the counting device of the metering arrangement is included in the control circuit 46. A volumetric scale 64 is provided on the container 12 in the same manner as in the Figure 3 embodiment.

This enables the total volume dispensed to be determined as described above in relation to the Figure 3 embodiment.

The Figure 4 embodiment also has one further feature as illustrated in Figure 4a, namely a pinch valve 68 disposed to control a flexible section of the medicament supply pipe 50 between the reservoir 48 and the container 12. The valve 68 includes a backing support 70, and a threaded element 72 arranged opposite the support 70 and rotatable manually for movement towards and away from the support 70. The flexible section of the pipe 50 extends between the support 70 and the element 72 and movement of the element 72 adjusts the section of the pipe 50 open to liquid flow.

In this manner, the rate of medicament flow into the container 12 can be altered to match appropriately the rate of water flow into the container 10 so that the liquid levels in the two containers rise simultaneously. Then, no imbalance occurs in the proportions of the liquid medicament and the water mixed in the common outlet 16, should dispensing take place during filling of these two containers.

Accordingly, the present invention provides a simple dispensing apparatus, in which the proportions of the liquids dispensed are maintained in a desired ratio. Additionally, the invention may provide for repeated operation of the dispensing cycle of the apparatus through replenishment of the containers 10 and 12.

Claims

1. Apparatus for supplying a liquid mixture, comprising a first container for a first liquid, a second container for a second liquid, and a common outlet for receiving and supplying the liquids from the first and second containers, the arrangement being such that the first and second liquids enter the common outlet in pre-determined proportions, the pre-determined proportions being determined at any particular time by the respective surface areas of the first and second liquids in the first and second containers at that time.

2. Apparatus as claimed in claim 1, in which the base of the first container is adapted to be in open communication with the base of the second container, in use, whereby the levels of the liquids in the first and second containers fall at respective pre-determined rates determined by the specific gravities of the liquids.

3. Apparatus as claimed in claim 1 or 2, further including control means operable, in response to the liquid in the first container falling below a predetermined level in the first container, to cause or permit the first container to be replenished.

4. Apparatus as claimed in claim 3, in which the control means include a supply valve in a supply pipe to the first container, and a control float which is arranged to cause the supply valve to open when the liquid in the first container falls below the pre-determined level.

5. Apparatus as claimed in claim 4, in which the supply valve is operable by a further float through a control arm attached to the further float, the further float being received in an auxiliary container having an outlet valve controlled by the control float.

6. Apparatus as claimed in claim 4, in which the supply valve is operable by an electronic circuit, and in which the electronic circuit is responsive to the control float for operating the supply valve.

7. Apparatus as claimed in any of claims 3 to 6, in which the control means are further operable, in response to the liquid in the first container falling below the pre-determined level in the first container, to cause or permit the second container to be replenished.

8. Apparatus as claimed in claim 7, when dependent from claim 4, in which a second supply valve is provided in a second supply pipe to the second container, and in which the control float is arranged to cause the second supply valve to open in response to the liquid in the first container falling below the pre-determined level.

9. Apparatus as claimed in claim 8, when dependent from claim 5, in which the second supply valve is operable by the further float by way of a further control arm.

10. Apparatus as claimed in claim 8, when dependent from claim 6, in which the second supply valve is operable by the electronic circuit in synchronism with the first supply valve.

11. Apparatus as claimed in any of claims 1 to 6, in which the second container is adapted to be replaced by a filled container when the second liquid falls below a pre-determined level in the second container.

12. Apparatus as claimed in any of claims 1 to 6, further comprising control means operable, in response to the second liquid falling below a predetermined level in the second container, to cause or permit the second container to be replenished.

13. Apparatus as claimed in any preceding claim, in which the common outlet includes a discharge valve adapted to dispense the liquids intermittently.

14. Apparatus as claimed in any of claims 1 to 12 in which the common outlet includes a discharge valve adapted to dispense the liquids continuously.

1 5. Apparatus as claimed in any of claims 1 to 12, in which the common outlet includes a discharge valve adapted to dispense the liquids on demand and intermittently or continuously.

16. Apparatus as claimed in any of claims 3 to 10, further comprising means for measuring the volume of the first and second liquids dispensed through the common outlet.

17. Apparatus as claimed in claim 16, in which the measuring means comprise means for counting the number of cycles during which the first container is emptied and replenished, and means for measuring the volumes of the first and second liquids dispensed from or remaining in the first and second containers at any moment in a particular cycle.

1 8. Apparatus substantially as herein particularly described with reference to and as illustrated in figures 1 a to 1 c; or figures 1 a to 1 c when modified by figure 2; or figures 1 a to 1 c when modified by figure 3; or figures 1 a to 1 c when modified by figure 4 of the accompanying drawings.