AU2017203429B2

AU2017203429B2 - Fluid Testing Device

Info

Publication number: AU2017203429B2
Application number: AU2017203429A
Authority: AU
Inventors: Shane Phillip Platts; Brett Adrian Reeve
Original assignee: Individual
Current assignee: Individual
Priority date: 2016-05-20
Filing date: 2017-05-22
Publication date: 2022-06-02
Anticipated expiration: 2037-05-22
Also published as: AU2017203429A1

Abstract

A fluid dispenser control system 1 including a solenoid valve (SV) 12, a pilot or toggle valve (PV) 14, two circuit valves (CV) 16a and 16b, one or more dispensing units 20, pipes 11 connecting all these parts together and an electrical cable 18. The exterior features on the dispensing unit 20 including two slots 22a and 22b, two elastic holding devices 23a and 23b, two rings 24a and 24b composed of a elastic material, two angled recesses 25a and 25b surrounding two dispensing holes 21a and 21b, three pneumatically actuated dispensing devices 26a, 26b and 26c, two pneumatic control system pipes 28a and 28d, a pneumatic purging pipe 28b, a testing fluid pipe 28c and a purging fluid pipe 28e. Figure 3 1/7 000 co (N ( co (CD LL

Description

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(CD LL FLUID TESTING DEVICE FIELD OF INVENTION

This invention relates to a device for dispensing testing fluids into testing containers in a controlled, food grade environment.

BACKGROUND ART

The following references to and descriptions of prior proposals or products are not intended to be, and are not to be construed as, statements or admissions of common general knowledge in the art. In particular, the following prior art discussion does not relate to what is commonly or well known by the person skilled in the art, but assists in the understanding of the inventive step of the present invention of which the identification of pertinent prior art proposals is but one part.

In previous sampling devices for sampling milk, milk may enter the purge and cleaning systems and may create build-up which may influence the testing results in subsequent milk samples. In addition, new sampling units added to an existing truck or existing facility for sampling milk generally require a controller to be added separate to the existing metering unit requiring additional initial purchase costs and ongoing maintenance and operating costs. In addition, sampling units do not have a place to hold test tube caps while the test tubes are being filled with testing fluid. This may result in foreign contaminants entering the testing fluid as operators generally place testing caps in their pockets or exposed to dust and other contaminants. In addition, the port through which milk or testing fluid exits previous sampling devices drips testing fluid after the intentional flow of testing fluid has stopped. This may result in product build up under the sampling device or additional testing fluid added to the testing container.

An object of the present invention is to ameliorate the aforementioned disadvantages of the prior art or to at least provide a useful alternative thereto.

STATEMENT OF INVENTION

The invention according to one or more aspects is as defined in the independent claims. Some optional and/or preferred features of the invention are defined in the dependent claims.

In a particularly preferred form, this invention relates to an electric and/or pneumatic powered sampling control system that may be adapted to be controlled by existing metering units.

Accordingly, in one aspect of the invention there is provided:

A fluid dispenser control system adapted to be controlled by a repeatable electrical signal active for a length of time, wherein the system includes:

a solenoid valve adapted to be actuated by the electrical signal for starting and stopping the flow of a system fluid past the solenoid valve and into the fluid dispenser control system, the solenoid valve activated by the electrical signal;

a toggle valve including a toggling mechanism, whereby the pressurisation or depressurisation of the fluid in the fluid dispenser control system with an initial applied pressure actuates the toggling mechanism, whereby the initial pressure is applied through the solenoid valve;

a system fluid circuit including a plurality of conduits and circuit valves that are adapted to charge the system fluid circuit with the system fluid, the path of the system fluid through the circuit adapted to be changed by the toggle valve; and

one or more testing fluid dispensing devices for dispensing a testing fluid into replaceable test tubes, the one or more testing fluid devices each including one or more dispensing ports,

wherein, the system fluid circuit is adapted to deliver the system fluid to power the actuation of the one or more testing fluid dispensing devices, which testing fluid devices are, in turn, adapted to control the flow of the testing fluid out of the dispensing ports and into the replaceable test tubes.

The plurality of conduits may be in the form of tubes and/or pipes. Preferably the plurality of conduits include tubes and pipes.

The replaceable test tubes may be composed of plastic, glass or similar materials. The test tube may or may not include a removable cap. Preferably, the test tubes include a removable cap.

The electrical signal may be electrical current supplied through an electrical cable. The electrical signal may be another form of electrical signal through an electrical cable. Preferably, the electrical signal is an electrical current supplied through an electrical cable. The electrical signal may be sent from an existing metering unit or existing device. The electrical signal may be sent from a controller. The electrical signal may be initiated by a switch and power supply which can be operated by an operator. Preferably, the electrical signal is sent from an existing metering unit.

A single electrical signal may be sent to the solenoid valve in the system fluid circuit for dispensing the required amount of testing fluid into the test tubes. Multiple electrical signals may be sent to the system fluid circuit in a sequence to perform different functions. For example, a first electrical signal may dispense testing fluid into a first test tube and a second electrical signal may dispense testing fluid into a second test tube.

The length of time of the repeatable electrical signal may change depending on the required volume of testing fluid to be dispensed into the test tubes. For example, if 40ml of testing fluid is required to be dispensed, the length of time may be 0.1 seconds. If 80ml of testing fluid is required to be dispensed, the length of time may be 0.2 second. This example is non-limiting and is used to provide understanding on the influence of the length of time on the volume of fluid dispensed. The length of time may vary between 0.05 seconds and 2 seconds, and preferably 0.1 - 0.2 seconds.

The system fluid may be air, water, hydraulic fluid or other suitable fluids for hydraulic or pneumatic actions. Preferably, the system fluid is air. Most preferably, the system fluid is compressed air.

Preferably, the system fluid circuit forms or connects the system together by pipes.

Most preferably, the system fluid circuit connects the solenoid valve, the toggle valve, the circuit valves and the testing fluid dispensing device together with pipes. Preferably, the circuit valves include pipes and valves which determine the path of fluid through some or all of multiple output pipes. The combination of output pipes, which are pressurised at a moment in time, is determined by the presence of fluid pressure to an input pipe and the configuration of the toggle valve. The configuration of the toggle valve depends on whether the toggle mechanism has been actuated or not.

The toggle valve may include two input pipes and one output pipe. The toggle valve may include one input pipe and two output pipes. The toggle valve may include multiple input pipes and multiple output pipes. Preferably, the toggle valve includes two input pipes and one output pipe. The toggling mechanism may have two or more configurations. Preferably, the toggling mechanism has two configurations. Preferably, the two configurations allow the output pipe of the toggle valve to be pressurised in a first configuration and does not allow pressurisation of the output pipe in a second configuration.

The pressure of the system fluid in the system fluid circuit may be any pressure greater than atmospheric pressure 101.3kPa. Preferably, the pressure of the system fluid in the system fluid circuit is over 11OkPa, and most preferably greater than 200kPa.

The path of the system fluid through the system fluid circuit may include fluid travelling on a single path. In other words, the path as represented schematically could be traced out by a single line. The path of the system fluid through the system fluid circuit may include branching paths. In other words, the fluid may travel in adjacent pipes or multiple separate pipes. Preferably, the path of the system fluid through the system fluid circuit includes branching paths.

Preferably, the dispensing device/s may control the flow of fluid such that they completely stop testing fluid flowing through the one or more dispensing devices ("the dispensing device/s") or completely allow testing fluid to flow through the dispensing device/s. The one or more dispensing devices may control the flow of system fluid such that the flow of the testing fluid is substantially stopped through the one or more dispensing devices in one system state or the testing fluid is substantially completely allowed to flow through the one or more dispensing devices in another system state.

The testing fluid may be water, milk or another liquid requiring testing.

The dispensing ports may include small holes in an underside face of the testing fluid dispensing device/s. The dispensing ports may include tubes or pipes connected to the testing fluid dispensing device/s. Preferably, the dispensing ports include small holes in the base of the testing fluid dispensing device/s.

The test tubes may be replaceable in that they can be placed into a holder in the testing fluid dispensing device to be filled with testing fluid and can be taken out of the holder. The test tubes may be replaceable in that they are disposable after use. Preferably, the test tubes are replaceable in that they can be placed into a holder in the testing fluid dispensing device and can be taken out of the holder.

In another aspect, the invention provides:

The fluid dispenser control system described above wherein the testing fluid dispensing device includes:

at least one purge valve; and

at least one dispensing valve;

wherein, the at least one purge valve is connected to or included in the end of one or more purge and cleaning pipes, such that there is no pipe section between the purge valve and the testing fluid dispensing device.

The at least one purge valve may be directly connected to the testing fluid dispensing device. The advantage of a purge valve being directly connected to the testing fluid dispensing device is that testing fluid build-up is significantly reduced or eliminated in the purge and cleaning pipes.

The purge valve and dispensing valve may include a solenoid valve. The purge valve and dispensing valve may include pneumatically actuated valves. The pneumatically actuated valves preferably are connected with pipes adapted to be pressurized for actuation of the cylinders inside the pneumatic valves. The actuation of the cylinders may allow or stop the flow of fluid through the valves. For example, the actuation of the valve or valves may involve a spring-extended, pneumatically actuated, valve.

The purge valve and dispensing valve may include a variety of sealing devices. For example, the purge valve and dispensing valve may include one or more O-ring seals. The O-rings may be axial or radial O-rings.

Preferably, the purge valve and dispensing valve may include pneumatically actuated valves. Most preferably, the purge valve and dispensing valve also include pressurised pipes for actuation of spring-extended cylinders inside the valves. The valves may use the O-rings as sealing means. Each pressurised pipe may include an exhaust hole, exhaust pipe and/or tube. Preferably, the pressurised pipe includes an exhaust pipe connected to an exhaust tube. Most preferably, the end of the exhaust tube is at a distance away from the fluid dispensing device such that the air intake and output is located in a dry area which does not come into contact with liquids.

The purge valve may be connected to a purge line or pipe. The purge line may receive a purge fluid. The fluid in the purge line may flush out the testing fluid in the testing fluid dispensing device. The fluid in the purge line may be a cleaning product or cleaning fluid. Preferably, the fluid in the purge line is air.

The purge valve and dispensing valve may be incorporated into the testing fluid dispensing device. The dispensing valve may be connected to the testing fluid dispensing device with no pipe between the dispensing valve and the testing fluid dispensing device. Preferably, the purge valve and the dispensing valve are incorporated into the testing fluid dispensing device.

In another aspect, the invention provides:

A cradle or holder below the dispensing ports to hold the test tubes;

An angled recess surrounding the dispensing ports to limit undesirable dripping after dispensing; and

An elastic holding device to hold the cap by applying pressure to the outer circumferential surfaces of the cap with an elastic material.

The cradle or holder may include a slot. The slot may be U-shaped. The slot may be oriented in a substantially horizontal plane. The slot may be configured whereby an outermost rim on the test tube container can slide into and is supported by the slot. The outermost rim of the typical test tube contemplated herein includes an upper portion on the container part of the test tube container and cap next to the base of the cap when the cap is screwed on and sealed.

The cradle or holder may include a step whereby the outermost rim can slide over and is held by the step. The cradle or holder may include a base with grooves or holes in which the test tube container can be contained in the directions parallel to the base of the test tube. The cradle or holder may include a set of spring-loaded claws to hold onto the circumferential surfaces of the test tube container. Preferably, the cradle or holder includes the slot.

The angled recess may form a truncated cone shape whereby the narrower end or smaller point of the cone is the location of the dispensing port. The angled recess may form a curved cone profile such as a parabola. The angled recess may be formed into an underside face of the testing fluid dispensing device, for example the angled recess may be cut into a flat surface. Preferably, the angled recess forms a cone shape and is cut or formed such that it is indented into the underside face.

The elastic holding device may include a cylindrical depression in the testing fluid dispensing device. The elastic holding device may include a groove to hold the elastic material. The elastic holding device may include recesses for holding the elastic material. Preferably, the elastic holding device includes a cylindrical depression in the testing fluid dispensing device with a groove to hold the elastic material. The elastic material may include an O-ring seal. The elastic material may include springs or elastically bendable plastic or metal parts. The elastic material may include rubber parts, such as rubber rings inserted into cylindrical recesses. The elastic material may be set in the elastic holding device such that there is interference between the elastic material and the test tube cap. The interference may apply holding or gripping pressure to the outer circumferential surfaces of the cap. The elastic holding device may therefore hold the cap inside or attached to the elastic holding device. Preferably, the elastic material includes an O-ring. The elastic holding device may include an O-ring seal. Most preferably, the O-ring is set inside a groove in the elastic holding device such that there is interference between the O-ring and the cap, when inserted.

The outer circumferential surfaces refer to the grip or the outermost surface or surfaces of the cap.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention may be better understood from the following non-limiting description of preferred embodiments, in which:

Figure 1 is a schematic diagram of a fluid dispenser control system;

Figure 2 is a front view of a dispensing unit with a test tube and a test tube cap inserted into the dispensing unit;

Figure 3 is a perspective underside view of the dispensing unit without the test tube and test tube cap inserted into the dispensing unit;

Figure 4 is a cross sectional front view of the dispensing unit dispensing testing fluid into a first test tube;

Figure 5 is a cross sectional front view of the dispensing unit dispensing testing fluid into a second test tube; and

Figure 6 is a cross sectional front view of the dispensing unit purging the dispensing unit of a purging fluid.

DETAILED DESCRIPTION OF THE DRAWINGS

Preferred features of the present invention will now be described with particular reference to the accompanying drawings. However, it is to be understood that the features illustrated in and described with reference to the drawings are not to be construed as limiting on the scope of the invention.

A fluid dispenser control system 1 including a solenoid valve (SV) 12, a pilot or toggle valve (PV) 14, two circuit valves (CV) 16a and 16b, one or more dispensing units 20, pipes 11,13,1517,19,28a,d connecting all these parts together such that they may be in fluid communication with their respective connecting parts, and an electrical cable 18. The exterior features on the dispensing unit 20 include two U-shaped slots 22a and 22b, two elastic holding devices 23a and 23b, two rings 24a and 24b composed of an elastic material, two angled recesses 25a and 25b surrounding two dispensing holes 21a and 21b, three pneumatically actuated dispensing devices 26a, 26b and 26c, two pneumatic control system pipes 28a and 28d, a pneumatic purging pipe 28b, a testing fluid pipe 28c and a purging fluid pipe 28e.

The test tubes 27a and 27b can slide into the slots 22b and 22a, respectively, the slots 22a,b lying in a substantially horizontal plane. The slots 22a,b have a lower supporting ledge and an upper ceiling surface. The lower ledge and the ceiling surface are opposed to each other and spaced to trap an annular flange of the test tubes 27a,b. When located in the slots 22a,b, the test tubes 27a,b depend downwardly from the slots 22a,b. The open mouths of the test tubes are thereby presented upwardly to the respective angled recesses 25a,b.

The rings 24a and 24b can be inserted into the elastic holding devices 23a and 23b, respectively. Test tube caps 29a and 29b can be inserted into the elastic holding devices 23b and 23a, respectively, and are held in place through interference fits with the rings 24a and 24b. The interference applies force to the outer circumferential surfaces of the test tube caps 29a and 29b, therefore gripping or applying friction to the surfaces, holding the caps in place.

The pneumatically actuated dispensing units 26a, 26b and 26c are actuated in response to air pressure in the pipes 28a, 28b and 28c, respectively. The pneumatically actuated dispensing devices 26a, 26b and 26c include actuated cylinders 30a, 30b and 30c and actuating springs 32a, 32b and 32c, respectively. The actuated cylinders 30a, 30b and 30c each respectively include a radial O-ring 37a, 38a and 39a, a first axial O-ring 37b, 38b and 39b and a second axial O-ring 37c, 38c and 39c, respectively. The actuating springs 32a, 32b and 32c are attached to the ends of each of the actuated cylinders 30a, 30b and 30c and the interior surface of the dispensing units 26a, 26b and 26c respectively, as shown in Figures 4 to 6.

The following discussion references as numeral "26" all three pneumatically actuated dispensing units 26a, 26b and 26c, their included components, and attached pipes 28a, 28b and 28c. The generic reference numerals for the cylinders 30a-c, springs 32a-c and the pipes 28a-c, namely respectively 30, 32 and 28, will be used.

The spring 32 is in an extended position when no pressure is applied in or to the pipe 28. The cylinder 30 lies in a channel or bore in the body of the dispensing device 26. No fluid can pass through the channel when the spring 32 and cylinder 30 are in the extended position. When the pipe 28 is pressurized, the cylinder 30 is forced further into the bore of the pneumatically actuated dispensing unit 26, such that the spring 32 is in a contracted position.

The purging fluid pipe 28e is connected to the purging fluid hole 36b and the testing fluid pipe 28c is connected to the testing fluid hole 36a. The fluid dispenser control system 1 dispenses a certain amount of fluid into the two test tubes 27a,b and purges the system 1 of testing fluid.

All the actions involved in this process will be referred to as the "sequence of system actions", which is divided up into the dispensing sequence of system actions and the purging sequence of system actions.

The dispensing sequence of system actions is as follows. A compressor (not shown) supplies compressed air to the pipe 11 before, during and after the sequence of system actions. An existing milk metering unit (not shown) supplies electricity through the electrical cable 18 to the solenoid valve 12.

It is advantageous for the fluid dispenser control system 1 to be controlled by the existing milk metering unit as it simplifies operation and reduces costs for manufacture, maintenance and electricity bills of the fluid dispenser control system 1.

The existing milk metering unit has limited control capabilities. More specifically, the electrical output from the existing milk metering unit is a repeatable single pulse of electricity, so the preferred embodiment of this invention described in detail herein has been adapted to be controlled by multiple single or discrete pulses of electricity. The length of the pulse is pre-set by the existing milk metering unit, according to the required volume to be dispensed into the test tubes 27a and 27b.

The solenoid valve 12 releases the pressurized air from the pipe 11 into the pipe 13. The second circuit valve 16b releases pressure into the pipe 17. The pilot valve 14 releases pressure into the pipe 15. The first circuit valve 16a releases pressure into the pipe 19. With the combination of both pipes 17 and 19 being pressurized, the circuit valves 16a and 16b release pressure into the pipe 28a. Pipe 28a is connected to the first pneumatically actuated dispensing device 26a. The first pneumatically actuated dispensing device 26a retracts a first actuated cylinder 30a further into the first pneumatically actuated dispensing device 26a, allowing testing fluid from the testing fluid pipe 28c to flow out of the testing fluid hole 21b, through the first dispensing channel 34a (which is an inclined channel as shown in Figs. 4 - 6) and into the first test tube 27a. The system 1 includes the at least three fluid dispensing devices 26a-b, including first dispensing device 26a adapted to dispense testing fluid to the first test tube 27a via the inclined channel 34a. The position of actuated cylinders 30a, 30b and 30c and flow of the testing fluid for this stage of the sequence of systems actions in which testing fluid is dispensed into the first test tube 27a, is shown in Figure 4. The arrows represent the flow of fluid. The testing fluid pipe 28c is pressurized before, during and after the sequence of system actions. The electricity supplied by the existing milk metering unit ceases, the solenoid valve 12 closes; thereby depressurizing the pipes 13, 15, 17, 19, 28a. The actuating cylinder 30a extends further out of the first pneumatically actuated dispensing device 26a, such that the O-ring 39b makes contact with the end of the shaft or bore in the body of the dispenser 26c. This stops the testing fluid from flowing from the testing fluid pipe 28c into the first test tube 27a. The pilot valve 14 automatically switches such that no pressure can be transferred from pipe 13 to pipe 15. This occurs upon relief of pressure from pipe 13.

The existing milk metering unit starts supplying electricity to actuate the solenoid valve 12 a second time. The solenoid valve 12 releases the pressurized air from pipe 11 into pipe 13 again. This time, the pilot valve 14 does not allow pressure to be transferred from pipe 13 into pipe 15. The second circuit valve 16b transfers pressure from pipe 13 into pipe 17. With the combination of pressurized pipe 17 and non-pressurized pipe 19, pipe 28d is pressurized through the circuit valves 16a and 16b. Pneumatic control system pipe 28d is connected to the third pneumatically actuated dispensing device 26c.

The third pneumatically actuated dispensing device 26c retracts a third actuated cylinder 30c inside the third pneumatically actuated dispensing device 26c, allowing the flow of testing fluid from the testing fluid hole 36a through the second dispensing channel 34b into the second test tube 27b. The electricity supplied by the existing milk metering unit ceases again, the solenoid valve 12 closes, which depressurizes pipes 13, 17 and 28d. The actuating cylinder extends inside the third pneumatically actuated dispensing device 26c which stops the flow of testing fluid from the testing fluid pipe 28c into the second test tube 27b. The position of actuated cylinders 30a, 30b and 30c and flow of the testing fluid for this dispensing stage of the sequence of systems actions in which testing fluid is dispensed into the third test tube 27c, is shown in Figure 5. The arrows represent the flow of fluid. The pilot valve 14 automatically switches, resetting the fluid dispenser control system 1 back to its original configuration, such that pressure is transferred to pipe 15 when pipe 13 is pressurised again. This switch is actuated upon relief of pressure in pipe 13. This ends the dispensing sequence of system actions.

After the dispensing sequence of system actions, the purge system activates to clean out the areas inside the dispensing unit 20 which were exposed to the testing fluid. The purging sequence of system actions is as follows:

The purging sequence involves the use of a purging fluid. The purging fluid used may be air or a cleaning solution. The purging fluid pipe 28b is pressurized with the purging fluid using a separate pressurization system. Pipe 28d is connected to the third pneumatically actuated dispensing device 26c. The second pneumatically actuated dispensing device 26b retracts a second actuated cylinder 30b further inside the second pneumatically actuated dispensing device 26b. This uncovers the purging fluid hole 36b and allows purging fluid to exit the purging fluid hole 36b. The purging fluid flushes out the testing fluid in the areas inside the dispensing unit 20 exposed to the testing fluid and exits through the first and second dispensing channels 34a and 34b, respectively. The position of actuated cylinders 30a, 30b and 30c and flow of the testing fluid when purging the dispensing unit of testing fluid, is shown in Figure 6. The arrows represent the flow of the purging fluid. The second dispensing unit pipe 28b is depressurized. This ends the purging sequence of system actions and therefore also the sequence of system actions.

As the actuating cylinders 30a, 30b and 30c extend and retract from the pneumatically actuated dispensing devices 26a, 26b and 26c, air is pushed out of and sucked into the space behind the radial O-ring 37c, 38c and 39c inside the actuated dispensing devices 26a, 26b and 26c. This air exchange moves air through the exhaust pipes 40a, 40b and 40c. The exhaust pipes 40a, 40b and 40c are connected to an air filter 42. The air filter 42is located in a dry area free from exposure to liquids. This is so that no liquids can enter the space behind the radial O-rings 37c, 38c and 39c inside the actuated dispensing devices 26a, 26b and 26c.

Throughout the specification and claims the word "comprise" and its derivatives are intended to have an inclusive rather than exclusive meaning unless the contrary is expressly stated or the context requires otherwise. That is, the word "comprise" and its derivatives will be taken to indicate the inclusion of not only the listed components, steps or features that it directly references, but also other components, steps or features not specifically listed, unless the contrary is expressly stated or the context requires otherwise.

In the present specification, terms such as "apparatus", "means", "device" and "member" may refer to singular or plural items and are terms intended to refer to a set of properties, functions or characteristics performed by one or more items or components having one or more parts. It is envisaged that where an "apparatus", "means", "device" or "member" or similar term is described as being a unitary object, then a functionally equivalent object having multiple components is considered to fall within the scope of the term, and similarly, where an "apparatus", "assembly", "means", "device" or "member" is described as having multiple components, a functionally equivalent but unitary object is also considered to fall within the scope of the term, unless the contrary is expressly stated or the context requires otherwise.

Orientational terms used in the specification and claims such as vertical, horizontal, top, bottom, upper and lower are to be interpreted as relational and are based on the premise that the component, item, article, apparatus, device or instrument will usually be considered in a particular orientation, which will usually be apparent from the context.

It will be appreciated by those skilled in the art that many modifications and variations may be made to the methods of the invention described herein without departing from the spirit and scope of the invention.

Claims

The claims defining the invention are as follows:

1. A fluid dispenser control system adapted to be controlled by a repeatable electrical signal active for a length of time, wherein the system includes:

a solenoid valve adapted to be actuated by the electrical signal for starting and stopping the flow of a system fluid past the solenoid valve and into of the fluid dispenser control system, the solenoid valve activated by the electrical signal;

one or more testing fluid dispensing devices for dispensing a testing fluid into replaceable test tubes, the one or more testing fluid dispensing devices each including one or more dispensing ports,

wherein, the system fluid circuit is adapted to deliver the system fluid to power the actuation of the one or more testing fluid dispensing devices, which testing fluid dispensing devices are, in turn, adapted to control the flow of the testing fluid out of the dispensing ports and into the replaceable test tubes.

2. The fluid dispenser control system as claimed in claim 1, wherein the testing fluid dispensing device includes:

at least one purge valve; and

at least one dispensing valve,

3. The fluid dispenser control system as claimed in claim 1 or 2, wherein the testing fluid dispensing device includes: a cradle or holder below the dispensing ports to hold the test tubes; an angled recess surrounding the dispensing ports to limit undesirable dripping after dispensing; and an elastic holding device to hold a cap of one of the replaceable test tubes by applying pressure to the outer circumferential surfaces of the cap with an elastic material.

4. The fluid dispenser control system as claimed in any one of the previous claims, wherein the one or more dispensing devices control the flow of system fluid such that the flow of the testing fluid is substantially stopped through the one or more dispensing devices in one system state or completely allow testing fluid to flow through the one or more dispensing devices in another system state.

5. The fluid dispenser control system as claimed in claim 2, wherein the at least one purge valve may be directly connected to the testing fluid dispensing device.

6. The fluid dispenser control system as claimed in claims 2 or 5, wherein one or both of the at least one purge valve and the at least one dispensing valve include -0 a solenoid valve.

7. The fluid dispenser control system as claimed in any one of claims 2, 5 or 6, wherein one or both of the at least one purge valve and the at least one dispensing valve include a pneumatically actuated valve.

8. The fluid dispenser control system as claimed in claim 7, wherein the or each pneumatically actuated valve is connected with pipes that are adapted to be pressurized for actuation of cylinders inside the pneumatic valve.

9. The fluid dispenser control system as claimed in claim 8, wherein the actuation of the cylinders either allows or stops the flow of system or purging fluid through the valves.

10. The fluid dispenser control system as claimed in claims 8 or 9, wherein the actuation of the valveorvalves involves a spring-extended, pneumatically actuated, valve.

11. The fluid dispenser control system as claimed in claim 3, wherein the cradle includes a U-shaped slot.

12. The fluid dispenser control system as claimed in claim 3 or 11, wherein the outermost rim of the test tube can slide into and is supported by the slot is a substantially horizontal orientation by providing a lower ledge and an upper ceiling structure to define the slot.

13. The fluid dispenser control system as claimed in claim 1, wherein the system includes at least three fluid dispensing devices, including first dispensing device adapted to dispense testing fluid to a test tube via an inclined channel.

14. The fluid dispenser control system as claimed in claim 13, wherein the system includes a second dispensing device that is opposed and inline with the first dispensing device.

15. The fluid dispenser control system as claimed in claim 13 or 14, wherein the system further includes a third dispensing device comprising a purging fluid hole adapted to deliver purging fluid through the inclined channel in a purging operation of the system.

16. The fluid dispenser control system as claimed in any one of claims 2 or 13 - 15, wherein the or each dispensing device is pneumatically actuated.

17. The fluid dispenser control system as claimed in any one of claims 2 or 13 - 16, wherein the actuation of the or each dispensing device involves the actuation of a spring-extended, pneumatically actuated, valve.

18. The fluid dispenser control system as claimed in claim 16 or 17, wherein the or each dispensing device includes an actuating cylinder adapted to extend and retract relative to the pneumatically actuated dispensing device.

19. The fluid dispenser control system as claimed in claim 18, wherein air is moved in an air exchange as air is pushed out of and sucked into the space behind a radial O-ring inside the or each actuated dispensing device.

20. The fluid dispenser control system as claimed in claim 19, wherein the air exchange moves air through one or more exhaust pipes connected to an air filter.