GB2035821A - Multiple automatic metering device - Google Patents

Abstract

A multiple automatic metering device particularly suitable for metering and admixing paints, and able to meter exact quantities of various base colours as to be able to obtain an extremely wide range of shades, comprises a series of units each comprising a container (3) for paint and a metering head (4) connected therewith. The device can be programmed to assure duplication of the metering operation and to ensure uniformity of the colour of various batches of final product. Each unit has a valve rod (6) with a communicating chamber (5) to open and close gasket valves (21, 23) so that selectively the paint can be moved between the container and the metering head as a drive plate (30) for all the units rises and falls, or paint in the head can be expelled through a discharge conduit 24 directed to a container as the plate falls. The discharge from each head is controlled by a counter operable by a drive from the plate. The plate 30 is connected to rods 19 which move pistons 20 in the metering heads and to rods 15 which extend through seals 48 into the containers 3 and are connected to mixing blades 16. <IMAGE>

Description

SPECIFICATION Multiple automatic metering device The present invention relates to a multiple automatic metering device, particularly suit able for use in dye works or the like, able to produce a large number of different colours by metering a limited number of base colours previously introduced in containers present in the device and discharging them simultaneously into a final container where they become admixed with each other forming a mixture of the desired final shade.

A preferred embodiment of the invention, to be later described, provides means to admix the base colours, avoiding the decantation thereof, control elements for all the operations of the machine, and means which permit the programming and memorization of various combinations of shades.

There is also provided control of all the functions of the metering device by means of a computer capable also of providing account ing of the machine output by visually showing the data on a display panel provided on a front part of the machine.

There is also provided the coupling of a metering head to each container and there are provided means for maintaining the product in continuous motion by making it flow from the container to the metering head and vice versa.

At the moment of discharge, a suitable device diverts the flow of the coloured mass which exists from the metering head toward the final container; when the metering operation is completed, the same device causes the flow of that portion of the coloured mass remaining in the metering head toward the container, as will be explained hereinafter in more detail.

There are presently known various types of metering device, used in numerous fields, from the food industry to the chemical field, metering devices which, in addition of having a rather limited accuracy, present substantial inconveniences when they are to be utilized with volatile products, highly viscous products or products which present a strong tendency to become dry; such inconveniences are particularly present when the operation of the machine is not continuous and are both due to the residues of product which, on drying, obstruct the conduits preventing subsequent exact dosage, and to the variations of the concentration of the content itself due to partial evaporation of the same.

The difficulty which must be overcome to eliminate such inconveniences is due to the fact that it is necessary to maintain the product in continuous motion in every part of the machine in order to prevent the formation of possible deposits and to the fact that the entire section in which the product circulates must be completely sealed.

In addition, such a device must be such as to permit an extremely accurate dosage, al lowing one to obtain a duplication of the operations even after some time has elapsed in order to obtain final products all of which have the same characteristics.

The present invention provides a metering device in which each container is permanently connected to its own metering head by a cylinder or the like, through which the product, mixed and maintained in constant motion by appropriate means, is made to pass from the container to the metering head and then made to return along the same path if not utilized.

At the moment of discharge, a valve inserted in the cylinder which connects the metering head and the container opens the discharge conduit, at the same time closing the passage from the metering head to the container, so that the product flows toward the discharge container.

The present invention will now be described in detail, by way of illustration and not of limitation, with particular reference to the accompanying drawings in which: Figure 1 is a plan view from above of the container's metering heads complex; Figure 2 is a section of a metering head container complex and the respective connecting chamber; Figure 3 shows a detail of the device for detecting the quantity of product discharged; Figure 4 shows a block diagram of the control circuits of the metering device; Figure 5 shows the perspective view of a single container; Figure 6 shows the perspective view of a blade present on the inside of the container; and Figure 7 shows a perspective view of a metering device according to the invention.

A series of units each of which comprises a container and a metering head are disposed preferably in a radial arrangement, thus forming a drum-shaped body 1 indicated as a whole in Fig. 1.

Each single unit comprises (Fig. 2) a container 3 closed at the upper end thereof by a hermetically sealing cover 14 and a metering head 4 connected to the container 3 by means of a chamber 5, preferably cylindrical, located at the lower portion thereof. To the upper end of container 3 are affixed sensors 18, of a known type for the control of the level of the colouring agent.

On the inside of chamber 5 slides a stem or shaft 6, controlled by an electrical valve 7 or the like, at one end of which are affixed, urged respectively by springs 22 and 22', gaskets 21 and 23 which, according to the position of the shaft, respectively close the opening 45 and open the passage 46 or vice versa. The opening 45 connects the chamber 5 with a second chamber 47, of smaller dimensions located below the metering head, which is in turn connected to chamber 47 through conduit 43.

The opening 46 connects the chamber 47 to a discharge conduit 24 directed toward the final container.

Above units 1, a plate 30, supported by a central shaft, not shown in the drawings, slides vertically in a recipricating motion. To the plate 30 are secured shafts 19, to each of which are affixed sealing rings 20 which slide on the inside of the metering heads 4, and shafts 1 5 which, through a sealed leakproof opening 48, extend into the containers 3.

At the end of each shaft 1 5 is located a blade 1 6 having a shape according to the internal section of the container (Fig. 6) tilted about its major axis and having a series of elastic elements 17, preferably of rubber, which slide along the walls of the container.

In addition the blade 30 (Fig. 3) is attached at 33 to a belt 32, preferably toothed, or the like, which cause the rotation of a toothed wheel 34 the teeth of which act, by interposing themselves to the path of a beam of light directed toward them, on a photocell 35 or the like connected to an impulse counter 36 of a known type.

Below the discharge orifices 24 a support platform 50 (Fig. 7) for the final containers may rotate about an axis 51. At the end of the support platform are located teeth 49 or the like which engage a stop, not indicated in the drawings, blocking the platform in position when a final discharge container is located below the orifices 24.

While the present application is directed essentially to the mechanical properties of the machine, there will now be supplied, purely by way of illustration, a summary description of an electronic circuit which may be suitably used to control the operation of the machine itself.

A feeder of a known type 37 (Fig. 4) is connected to a push-button panel 38 which also comprises a visualizer, to a microprocessor 39, to memories 40, to each valve 7 and to respective controls 41.

Between the feeder 37 and the memories 40 is inserted a battery 42 equipped with a device to connect it to the memories in case of interruption of the feed current.

The operation takes place as follows: Initially a motor puts in motion, through a reductor, an oleodynamic circuit, or the like, the plate 30. In each unit the stem 6 is in the position shown in Fig. 2 in which the opening 46 is closed while the passage between the chamber 5 and the metering head 4 is open.

Each piston ring 20, in its upward movement, such the colouring agent from the respective container 3 and then pushes it back into the container during its downward travel.

In this manner, the colours present in the containers 3 are thoroughly admixed, both by means of the blades 1 6 and by the motion from the containers 3 to the respective meter ing heads 4 and vice versa. The elastic ele ments 1 7 fixed onto the blades serve not only to guide the blades themselves but to temove the colouring agent from the walls of the container, thus permitting visual observation of the level from the outside of each container.

At the other end of the mixing operation, the microprocessor unblocks the other functions of the machine and it is now possible to set on the push-button panel the command corresponding to the preselected colour shade. The combination of base colours, in the different quantities apt to furnish various shades, will have been previously memorized and the battery 42, with the device which connects it immediately to the memories in case of interruption of the current, has the scope of maintaining the latter always active, furnishing them with the necessary feed current.

Once the control corresponding to a desired colour is set, the microprocessor senses the presence of the collecting container in register with the discharge outlets 24 by means of photocells or the like, detects the dimensions thereof and ascertains through the memories that in the relevant containers 3 the base colour is present in sufficient quantity, and then activates the discharge operation.

To discharge, when the plate 30 has reached the maximum height and the metering heads 4 are completely filled, the microprocessor activates the valves 7 corresponding to the desired colours which push the stems 6 so as to close the passage 45 and open the paths 46 toward the discharges 24. Then the piston rings 20, during the downward movement of the plate 30 will discharge simultaneously the colours in the final container.

The dosages will be controlled by the microprocessor by means of the device shown in Fig. 3. The quantity of material discharged from each metering head is a function of the lowering of the plate 30, measured by means of the impulse counter 36, which counts the number of teeth which pass in front of the photocell 35. Since the toothed wheel 34 is driven by the belt 32 connected to the plate 30, it is clear that the passage of a tooth in front of the cell 35 corresponds to an exact lowering distance of the plate which causes the discharge of a pre-determined quantity of colour from the metering heads 4.

From the impulse counter 36 the signals are sent to the microprocessor which, as soon as a colour has been discharged in the exact amount, activates the corresponding valve 7 closing the passage 46 and opening the hole 45 so as to permit the back-flow into the container 3 of all the colour remaining in the metering head and not discharged.

The amount of each colour used is then memorized. The discharge from the various containers takes place simultaneously com manded by the microprocessors, as are the valves, which close automatically at the end of each single dosage.

The support platform 50 may be rotated so that it will not extend beyond the body of the machine during transport and has a double body configuration so as to permit, when one of the containers is filled, the positioning of the following one.

In addition, the microprocessor, other than for the control of the operation of the ma chine, may also be utilized for other uses: for example, there is considered its utilization to cause the appearance on the visualizator of publicity messages when the machine is not in use; it is also further possible to use it as a calculator and in particular to keep daily accounting of the machine.

Claims (5)

1. A multiple automatic metering device for metering and admixing paints or other fluids, wherein there are provided a series of units each of which comprises a container for an individual fluid and a metering head connected to each other by a communicating chamber having valve means and a discharge conduit directed toward a single central collecting container, in each container and in each metering head there being provided stems movable in unison by a single plate capable of reciprocating movement, said stems being connected respectively to mixing blades in the containers and to sealing pistion rings in the metering heads, so that in one position of each said valve means there is a flow of the product to be dosed from the containers to the metering heads and vice versa under the action of the reciprocating movement of the plate and that in the other position of each said valve means the metering heads may discharge their contents directly through the discharge conduits, communication between the heads containers being obstructed.

2. A multiple automatic metering device according to claim 1, wherein each valve means is operated by a single electrically operated valve controlled by a microprocessor, a number of valves being operable simultaneously to determine the dosage from a plurality of units.

3. A multiple automatic metering device according to claim 1 or 2, wherein the plate is connected to a rotary interception organ of a counter so that the number of impulses generated by said counter is proportional to the descent of the plate and thus to the quantity of substance introducted by the metering head into the discharge conduit.

4. A multiple automatic metering device according to claims 1, 2 or 3, wherein said valve means located in the communication chamber between each container and its metering head comprising a stem on which is resiliently mounted a first gasket for interrupting communication between the metering head and the container, the stem having one end within a chamber communicating with the discharge conduit and having an interior sleeve carrying a further gasket to interrupt communication between the metering head and discharge conduit, and a spring which urges the sleeve and tends to keep said further gasket to a closed position, the valve means being operable so that movement of the stem closes in one direction first the first gasket to interrupt communication between the metering head and the container and subsequently moves the second gasket against the spring to open communication beween the metering head and the discharge conduit.

5. A multiple automatic metering device constructed and arranged substantially as hereinbefore described and shown in the accompanying drawings.