GB2111461A - Supply apparatus for supplying metered quantities of flowable media - Google Patents

Abstract

Supply apparatus for individual metered conveying of fluid from a respective supply container (1 to 5) into a common working container (35) and for the mixing of the fluid with a working medium comprises individually drivable valves (12 to 17) for connecting the supply containers (1 to 5) and a working medium suction duct (11) to a collecting channel (19). A collective output (20) of the channel (19) is connectible with the working container (35) through a pump (21) closing in air-tight manner. Such apparatus can be employed for the individual metered conveying of pumpable washing agents, which are to be mixed with washing water, from the supply containers into the container of a washing machine. <IMAGE>

Description

SPECIFICATION Supply apparatus for supplying metered quantities of flowable media The present invention relates to apparatus for supplying metered quantities of flowable media, and has particular reference to apparatus for conveying pumpable effective substances each from a respective supply container into a common working container and for the mixing of such substances with a working medium. The effective substances may be, for example, washing agent effective substances, the working medium may be water, and the working container may be the liquor container of a washing machine.

Apparatus for the addition and metering of a cleaning agent, which consists of several components incompatible with each other in liquid state, is disclosed in German (Fed. Rep.) published patent Application 17 60 512. Separately stored liquid components are at certain times and in metered quantities conveyed by means of this apparatus into a washing container. The composition of the cleaning agent always remains the same because the individual quantities of the conveyed metered components are predetermined by the clear width of the hose of a hose roller pump employed for this purpose. In the case of washing machines, however, differing compositions of the cleaning agent are required according to the type and quantity of laundry, so that the known apparatus is not suitable for use in washing machines.

DE-OS 24 G1 700 describes control and injection apparatus for additives in a laundry machine, wherein for each separately stored liquid additive a separate pump is provided, which is set into motion at the appropriate time by a respective time control mechanism and then remains switched on for a time corresponding to the quantity to be metered. The expenditure involved with separate pumps and time control mechanisms is too high for washing machines or dishwashing machines for the domestic field, and entails a substantial space requirement and high production costs. Moreover, the known apparatus does not include precautionary measures for avoiding dehydration or crystallisation of the liquid additives, which can come into contact with the atmosphere at least at the openings of the pump ducts.

DE-OS 25 54 592 describes an automatic washing machine in which the above-mentioned disadvantages are largely avoided. However, the expenditure is still very high as, for example, six pumps are provided each in association with a respective supply container, although these pumps can be operated from a common drive.

Each pump must, however, be associated with a switchable clutch in order that the effective substances can be fed individually and in varying quantities to a premixing channel which, after the metering of the substances, is rinsed through and cleaned by circulating water. Residues of the substances then do not remain in this channel and crust or crystallise. it is possible for the premixing channel to be constructed so as to be constantly filled with water through an overflow elbow and thereby close off the openings of the pumps from the atmosphere. All arrangements, however, still require a relatively large overall space and involve high production costs. The multiplicity of pumps and clutches increases susceptibility to faults.

Moreover, the known washing machine requires in the drainage system either a switchable water shunt or a separate circulation pump for circulation of the washing liquor already in the washing container.

According to the present invention there is provided supply apparatus for supplying metered quantities of flowable media, comprising a plurality of containers each for containing a flowable medium, duct means for conducting a liquid miscible with each flowable medium, a collecting chamber, a plurality of individually operable valves for selectively connecting the containers and duct means to the collecting chamber, and a pump connected to an outlet of the collecting chamber and operable in an air-tight manner to pump out any such liquid and any such flowable medium present in the collecting chamber.

In a preferred embodiment, the supply containers and a working medium suction duct are connectible through individually drivable valves to a collecting channel, a collective output of which is connectible with a working container through a pump closing in air-tight manner. Thus, only a single pump is necessary for all stored effective substances and the valves, one of which is provided for each supply container, can be of relatively simple construction. All components of the apparatus can be so arranged that the effective substances are hermetically sealed off from the atmosphere in the non-operating state of the apparatus.

Embodiments of the present invention will now be more particularly described by way of example with reference to the accompanying drawings, in which: Fig. 1 is a schematic diagram of a first apparatus embodying the invention; Fig. 2 is a partly sectional plan view of a valve and pump unit of a second apparatus embodying the invention; Fig. 3 is a cross-section along the line Ill-Ill of Fig. 2; Fig. 4 is a block circuit diagram of control means for controlling valve operation in the case of a reversible rotary drive pump motor of apparatus embodying the invention; and Fig. 5 is a block circuit diagram of control means for controlling valve operation in the case of a unidirectional motor and switchable clutches of apparatus embodying the invention.

Referring now to the drawings, five effective substance containers 1 to 5 are connected through ducts 6 to 10 to individually drivable valves 13 to 17, the valves being connected to a collecting channel 19. Through an additional duct 11 , which stands in connection with water or liquor in a container 35 of a washing appliance (not shown in detail), and a valve 12, the container 35 is connected with the channel 19. Operation of the valves is controlled by a control device 33 which comprises setting indicators 26 to 32 and which is drivable by a motor 23 through a clutch 24. The control device 33 together with the collecting channel 19 is associated with valves in a valve unit 18.

The collecting channel 19 is so arranged that it can be well rinsed by water or liquor from the container 50 so that any residual quantities of effective substances, possibly running out of the valves 13 to 1 7 during standstill times of the pump 21, cannot intermix. This can be achieved in the collecting channel 19, which is represented in extended form, by an inserted worm 34 subdividing the channel 19 into individual chambers.

These chambers are, however, so interconnected in series that, with the valve 12 open and a pump 21 running, circulating water can flow through the channel 19 at high throughflow speed in the direction of the arrows.

in the embodiment to be later described with reference to Figs. 2 and 3, the afore-mentioned requirements are fulfilled by a different construction of the valves and collecting channel.

Whenever one of the valves 12 to 1 7 is opened, the medium concerned can be sucked out of the collecting channel 19 through a duct 20 by the pump 21 and conveyed through a duct 22 into the container 35. The motor 23 is provided as drive for the control device 33 and the pump 21. This motor can be coupled by means of a clutch 24 to the control device 33 or by means of a clutch 25 to the pump 21.

A particularly simple arrangement is in fact possible if the motor 23 is reversible in rotational direction. Then freewheel clutches can be used as the clutches 24 and 25, one of which transmits drive in one rotational direction and the other transmits drive in the other rotational direction.

Then, either the control device 33 or the pump 21 can be driven selectably through simple reversal of the rotational direction of the motor 23. If the pump is of a type that conveys in only one rotational direction, the coupling 25 could be dispensed with; the motor 23 and pump 21 could then be rigidly interconnected. While the pump, for example, conveys in one rotational direction, the clutch 24 would then have to transmit drive in the other rotational direction.

The control device 33 is provided with setting indicators 26 to 32 which mark the respective setting of the valves 12 to 1 7. These indicators can be of a mechanial, electrical or magnetic kind, for example a combination of magnets and reed switches, a contact wiping on a contact track, or a cam acting on contact pairs. The indicator 26 indicates a rest position 37 in which all valves 12 to 17 are closed. The indicators can be controlled either directly by the valves or through a control disc, which has a course associated with the valve position.

The indicators can influence the course of the metering process in two different ways. For example, the indicators can be connected into the control current circuit and, on the attainment of the valve position selected by control means (not shown), can signal the attained position back to the control means, whereby the control means is caused to switch on the pump 21. Another possibility is to include the indicators directly in the current circuit of the pump drive. The switching over from valve selection to pump drive can then take place directly through the respective indicator.

For this case, the motor 23, which is reversible in rotational direction, is driven through one of the indicators 27 to 32 of the respectively selected valve 12 to 17. This means that the motor is operated in the rotational direction for driving the control device 33 until the position marked in the indicator, for example 29, for the valve. for example 14, is reached. The motor 23 is then switched over in its direction of rotation and drives the pump 21. The duration of the pumping process is proportional to the metered quantity and is determined by the control means (not shown).When it is anticipated that the conveying performance of the pump 21 will fluctuate to an appreciable extent in consequence of differing viscosities of the effective substances or different heights of conveying, then the time-dependent control of the pumping operation can be varried in dependence on a throughflow meter arranged in the flow path of the duct 20 or 22 or devolve exclusively in dependence on throughflow measurement.

The control device 33 with the indicators 26 to 32 and the valves 12 to 17, the pump 21, the drive motor 23 and the clutches 24 and 25 can be combined into a compact metering unit in particularly simple manner as illustrated in Figs. 2 and 3. Fig. 2 in plan view shows a partially sectioned metering unit which is housed in a flat cylinder housing 180. The housing consists of two shells, a lower one of which houses the ducts to and from the valves and to the collecting channel 19 and is connected with the housing of the motor 23. The valve 16, which is representative of all the other valves, comprises a bow rocker 1 60. which is mounted in the housing shell at the side of the motor and the bow of which can be pressed against a length of hose 161 of resilient material.

whereby the hose is compressed and completely closes off its internal passage. A contact pressure plate 162, which is pressed by a spring 163 against the hose 161, is disposed under the bow of the rocker 1 60 in the shell at the side of the motor. The valve 16 is closed in the setting of the bow rocker 160 shown in Fig. 3. The supply container 4 (Fig. 1) connected to the duct 9 therefore cannot deliver its content into the collecting channel 19, which in the embodiment of Figs. 2 and 3 has an annular structure. The duct 20 is connected to the collecting channel 19 and leads to the pump 21, via the housing opening pointing upwards in Fig. 2 and to the right in Fig.

3. No valve is provided in the housing 180 for this opening. The ducts 6 to 10, led to stub pipes arranged in star shape, are closed off by the valves 13 to 17 from the annular collecting channel 19 or individually opened, according to the setting of the control device 33.

The control device 33 is arranged in the housing part (at the bottom of Fig. 3) facing the observer in Fig. 2. It contains a control disc 330, which is rotatably mounted in the housing shell.

This control disc 330 presses the bows of all valve rockers against the associated hose lengths when the control disc is disposed in a rest position. In the illustrated setting of Fig. 2, the control disc is disposed so that the valve 17 (the upper one of both the visible valves) is opened. Its associated bow rocker 170 is thus raised and frees the hose 1 71. Disposed at this point of the switching disc 330 is a depression (not illustrated) which lies on the circle of the contact points of all rocker bows and into which the bow of the rocker 170 drops aided by the resilience of the material of the hose.

The control device also includes an annular conductor plate 331, to which magnetically sensitive components, for example Hall integrated circuits 333, are soldered at suitable points 332.

Provided at certain points of the circumference of the switching disc 330 are magnetic zones 334, which on being placed opposite the Hall integrated circuits 333 deliver a signal through the conductor plate 331 to the contact pins 335, the signal being processed in the control means (not shown) into a certain angular setting of the control disc 330. For the possible eight positions of the control disc 330 in the embodiment of Figs. 2 and 3, preferably four points 332 are provided, at which Hall integrated circuits 333 are incorporated and can correspond with four magnetic zones 334.

An output shaft 230 of the motor ends within the housing 180. It is there non-rotatably connected with a coupling flange 231 , which through an inwardly acting ratchet gear 232 can rotationally entrain a shaft 210 of the pump 21 for clockwise rotation (Fig. 2). Arranged on the pump shaft 210 is a roller star 211, the rollers of which circulatingly squeeze off a hose 213 arranged in a housing 212 of the pump and thereby convey the liquid present therein to the outlet duct 22.

The coupling flange 231 acts outwardly through a further ratchet gear 233 on the control disc 330. Insofar as the coupling flange 231 turns with the motor shaft 230 in the counterclockwise direction (Fig. 2), the control disc 330 rotates in the same direction. The depression in the control disc 330 then moves to the bow of the next rocker and opens the associated valve. When a required combination results from the Hall integrated circuits 333 and magnetiz zones 334 being disposed in correspondence with each other, the rotational direction of the motor 23 is switched over so that the switching disc 330 remains still, leaving the switched valve opened, and the pump is driven.The pump then sucks effective substance out of the supply container 4 through the hose 20, the annular channel 19, the valve 16 and the duct 9 until the control means terminates the pumping operation. Then, the rotational direction of the motor 23 is again reversed so that the disc 330 is moved to a new valve setting.

When the disc reaches the valve setting pointing upwardly to the right in Fig. 2, the suction duct 11 is connected with the channel 19, which includes a separating wall (not shown) between this opening and the opening of the suction hose 20.

The rotational direction of the motor 23 is again switched over (now to clockwise sense) so that the pump 21 conveys water out of the container 35 through the duct 11, the valve 12, the channel 19, the duct 20, the pump 21 and the duct 22 back to the container 35. The circulating water flows through the entire channel 19 from the top at the right in clockwise direction so that all valve openings are turbulently flowed around by the water and freed of residues of effective substances. In this manner, all effective substances previously sucked in through the channel 19 can be conveyed into the container 35.

When the control disc 330 is so set that its depression comes to stand under the hose 20, its rest position is assumed. In this setting, all seven valves arranged in the valve unit 18 are closed.

The valve associated with the stub pipe Z is not connected to any supply container in the illustrated embodiment. It can be closed off by a stopper for the purpose of avoiding the induction of air. This stub pipe can be utilized for the connection of a further supply container if so desired.

Illustrated in each of Figs. 4 and 5 is a respective possible circuit for the indicators 26 to 32 connected into the current circuit of the pump motor 23 on the use of a motor reversible in direction of rotation (for example a capacitor motor) or a motor operating in one rotational direction and associated with clutches 37 and 38 which are, for example, switchable through magnets.

The course of a metering operation will now be explained more closely with reference to these circuits in conjunction with the Fig. 1.

Before the start of the metering operation, the valve unit 18 is in the rest position, in which the indicators 26 to 32 are disposed in the switch setting illustrated in Figs. 4 and 5. In this position, all valves 12 to 17 are closed and the motor 23 is free of current. When a control 36 requires an effective substance from the supply container 1, then the motor 23 is so supplied by the control 36 through the contacts I-Il, which are closed when the valve 13 is closed, of the indicator 28, which can for example be a read switch, that it drives the control device 33 through the directional clutch 24. As soon as the control device 33 has opened the desired valve 13, the indicator 28 switches over to the contacts I and Ill so that the rotational direction of the motor 23 is changed and the motor now drives the pump 21 through the directional clutch 25.The control 36 includes a circuit by means of which the pump operation can be limited in time. Thereby, a respectively desired quantity of the substance is conveyed. At the conclusion of the pump operation, the line leading to the indicator 28 is switched off from the control 36 and the line leading to the indicator 27 is switched on. Since the associated valve 12 is closed, the indicator is disposed in the switch position I and II, whereby the motor 23 now runs again in the original rotational direction, in which the control device 33 is driven. The control device 33 runs until the valve 12 is opened, whereby the indicator 27 switches over to the contacts I and Ill and switches the rotational direction of the motor 23 back to pump operation.Water is now sucked through the duct 11 out of the container 35 and conveys the substance metered out of the supply container 1 into the channel 19 through the paths described above and into the container 35.

After conclusion of this rinsing-in operation, the control 36 terminates this operation by switching off the line leading to the indicator 27 and switching back on the line leading to the indicator 26. This indicator has its contacts 1 and 2 closed so that the motor 23 again sets the control device 33 into motion until the switching disc (330, Fig. 3) has arrived in the rest position, in which the indicator 26 closes the contacts I and ill. Thereby, the motor 23 is switched off; all valves 12 to 17 are closed, all other indicators 27 to 32 therefore have their contacts I and II closed and the metering operation is terminated.

When two or more components are to be metered immediately one after the other, then the switching over from one supply container to the other can be undertaken directly and an intermediate rinsing with water or liquor and overriding of the rest position can be omitted.

Fig. 5 shows a circuit corresponding to that of Fig. 4 but in which, instead of reversing the rotational direction of the motor 23, respective switching magnets 37 and 38 for the clutches 24 and 25 are switched on or off by the indicators 26 to 32.

Claims (14)

1. Supply apparatus for supplying metered quantities of flowable media, comprising a plurality of containers each for containing a flowable medium, duct means for conducting a liquid miscible with each flowable medium, a collecting chamber, a plurality of individually operable valves for selectively connecting the container and duct means to the collecting chamber, and a pump connected to an outlet of the collecting chamber and operable in an air-tight manner to pump out any such liquid and any such flowable medium present in the collecting chamber.

2. Apparatus as claimed in claim 1, comprising a control device for controlling operation of the valves and a single motor to drive both the pump and the control device, the motor being coupled to each of the pump and the control device by means of a respective switchable clutch.

3. Apparatus as claimed in claim 1, comprising a control device for controlling operation of the valves and a reversible rotary drive motor coupled to drive the pump in one rotational drive direction and the control device in the other rotational drive direction.

4. Apparatus as claimed in claim 3, wherein the motor is coupled to each of the pump and the control device by a respective free-wheel clutch arranged to transmit drive in the respective rotational direction.

5. Apparatus as claimed in any one of claims 2 to 4, wherein the valves and the collecting chamber are disposed in a housing, the valves being arranged in radial format around the chamber.

6. Apparatus as claimed in claim 5, wherein each of the valves comprises a respective resilient hose portion and respective closure member movable to compress the hose portion.

7. Apparatus as claimed in claim 6, wherein each of the closure members comprises a bowshaped rocker.

8. Apparatus as claimed in either claim 6 or claim 7, wherein the control device comprises a control disc co-operable with the closure members to control movement thereof.

9. Apparatus as claimed in any one of the preceding claims, comprising means to operate the valves in a sequence ending with all of the valves in a closed setting.

10. Apparatus as claimed in any one of the preceding claims, the pump comprising a hose roller pump.

11. Supply apparatus substantially as hereinbefore described with reference to Fig. 1 of the accompanying drawings.

12. Supply apparatus substantially as hereinbefore described with reference to Figs. 2 and 3 of the accompanying drawings.

13. Supply apparatus substantially as hereinbefore described with reference to Fig. 4 of the accompanying drawings.

14. Supply apparatus substantially as hereinbefore described with reference to Fig. 5 of the accompanying drawings.